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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

Mechanical Behaviors of Ti-Si-N Coatings Deposited by Bias Sputtering

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稀有金属材料与工程 2012年第S1期41卷 18-23页

作者： p w Shum Advanced Coatings Applied Research Laboratory(ACARL) Department of Mechanical and Biomedical Engineering(MBE)City University of Hong KongHong KongChina

Ti-Si-N hard coatings were deposited on steel substrates by reactive unbalanced magnetron sputtering from Ti and Si elemental targets in a mixture of Ar and N2 *** influences of negative bias voltage(in the range of-30 to-80 V)on the mechanical properties of the coatings were *** particular,the critical cycle during dynamic impact tests was employed to indicate the bonding strength of the *** was found that the Ti-Si-N coatings prepared at lower constant bias voltages could effectively improve the adhesion and the cyclic impact performance,but their hardness was dropped significantly to 13 Gpa at a bias of-30 *** bias voltage values induced greater hardness.A maximum hardness of 47 Gpa was obtained at a bias of-60 ***,the coating adhesion was worse in this case,and the number of impact cycles(～8×10 3)that the coatings could endure was much shorter than that of TiN binary coatings(～2×104).On the other hand,the bias voltage was varied linearly from-40 to-60 V during Ti-Si-N *** this circumstance,the hardness of the coatings deposited with the bias-graded configuration remained very high(42 Gpa),and the adhesion strength was improved ***,the critical impact cycle could reach as high as 1.8×***,bias-graded deposition can provide an effective processing route to prepare Ti-Si-N superhard coatings with high adhesion strength and impact resistance.

关键词： Ti-Si-N coatings magnetron sputtering bias voltage mechanical properties impact test

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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Neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital Nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research Unit for Neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

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Neural Regeneration Research 2025年第3期20卷 725-739页

作者： Benjamin R.Helmold Angela Ahrens Zachary Fitzgerald p.Hande Ozdinler Department of Neurology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Center for Molecular Innovation and Drug Discovery Center for Developmental TherapeuticsChemistry of Life Processes InstituteNorthwestern UniversityEvanstonILUSA Mesulam Center for Cognitive Neurology and Alzheimer’s Disease Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Feinberg School of Medicine Les Turner ALS Center at Northwestern UniversityChicagoILUSA

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

关键词： ALS2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SpAST spastin

Spin switching in antiferromagnets using Néel-order spin-orbit torques

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Chinese physics B 2018年第10期27卷 88-95页

作者： p wadley K w Edmonds School of physics and Astronomy University of Nottingham

Antiferromagnets offer considerable potential for electronic device applications. This article reviews recent demonstrations of spin manipulation in antiferromagnetic devices using applied electrical currents. Due to spin–orbit coupling in environments with particular crystalline or structural symmetries, the electric current can induce an effective magnetic field with a sign that alternates on the lengthscale of the unit cell. The staggered effective field provides an efficient mechanism for switching antiferromagnetic domains and moving antiferromagnetic domain walls, with writing speeds in the terahertz regime.

关键词： spintronics antiferromagnetic current-induced torques magnetic domains

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

Feasibility Study of Using DLC Coating in Conjunction with Laser Ablation process to Improve the Tribological performance of an Engineering Surface

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稀有金属材料与工程 2012年第S1期41卷 52-56页

作者： Shum p w Department of Manufacturing Engineering and Engineering Management(MEEM) City University of Hong KongHong KongChina

Increasing demands such as low friction,low wear rate,and long life-time have reached the limits of single DLC *** order to meet the requirements,we propose to use an integrated approach to improve the wear property of an engineering ***,dimples are introduced perpendicular to an engineering surface by a Nd:YAG laser emitting at 1064 ***,solid lubricant DLC is prepared on the patterned surface by magnetron sputtering *** effect of dimple densities from 7%to 45 %on tribological properties of the coating surface was *** wear performance of the textured DLC surfaces was studied by a pin-on-disk reciprocating sliding wear tester under boundary lubrication and dry *** results showed that the DLC coatings with appropriate dimple densities have an obvious improvement on wear performance in term of friction coefficient,wear rate and wear life,as compared to un-textured DLC *** boundary lubrication conditions,the improved wear performance can be explained by the promotion of reservoirs to enhance lubricant retention during *** dry condition,the dimples trap wear particles and leave a free interface between pin and sliding contact surface,and avoid the surface worn by abrasive manner,thereby improving the wear performance of the DLC coating.

关键词： laser wear DLC

Machine learning applications in healthcare clinical practice and research

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world Journal of Clinical Cases 2025年第1期13卷 16-21页

作者： Nikolaos-Achilleas Arkoudis stavros p papadakos Research Unit of Radiology and Medical Imaging School of MedicineNational and Kapodistrian University of AthensAthens 11528Greece 2^(nd)Department of Radiology “Attikon”General University HospitalMedical SchoolNational and Kapodistrian University of AthensChaidari 12462Greece Department of Gastroenterology Laiko General HospitalNational and Kapodistrian University of AthensAthens 11527Greece

Machine learning(ML)is a type of artificial intelligence that assists computers in the acquisition of knowledge through data analysis,thus creating machines that can complete tasks otherwise requiring human *** its various applications,it has proven groundbreaking in healthcare as well,both in clinical practice and *** this editorial,we succinctly introduce ML applications and present a study,featured in the latest issue of the world Journal of Clinical *** authors of this study conducted an analysis using both multiple linear regression(MLR)and ML methods to investigate the significant factors that may impact the estimated glomerular filtration rate in healthy women with and without non-alcoholic fatty liver disease(NAFLD).Their results implicated age as the most important determining factor in both groups,followed by lactic dehydrogenase,uric acid,forced expiratory volume in one second,and *** addition,for the NAFLD-group,the 5th and 6th most important impact factors were thyroid-stimulating hormone and systolic blood pressure,as compared to plasma calcium and body fat for the NAFLD+***,the study's distinctive contribution lies in its adoption of ML methodologies,showcasing their superiority over traditional statistical approaches(herein MLR),thereby highlighting the potential of ML to represent an invaluable advanced adjunct tool in clinical practice and research.

关键词： Machine Learning Artificial Intelligence Clinical practice Research Glomerular filtration rate Non-alcoholic fatty liver disease Medicine

Deformation Strength of Nanocrystalline Thin Films

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Journal of Materials Science & Technology 2017年第7期33卷 718-722页

作者： w.Blum p.Eisenlohr Department of Chemical Engineering and Materials Science Michigan State University East Lansing M148824 USA

The data of deformation strength and microstructure of thin films of nanocrystalline pd recently provided by Colla et al. have been analysed. It is shown that the properties of the films with cylindrical grains of30 nm diameter extending over a significant portion of the film thickness（≈90 nm） are quantitatively comparable to what is known from nanocrystalline bulk material. This is explained in terms of boundarymediated processes governing emission, storage, and recovery of dislocations.

关键词： Stress relaxation Thin Film Nanocrystalline pd In situ Dislocations

Improving the wind and temperature measurements of an airborne meteorological measuring system

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2012年第10期13卷 723-746页

作者： Stephen FOSTER p.w.CHAN Aventech Research Inc. BarrieON L4N 2E3Canada Hong Kong Observatory KowloonHong KongChina

The Aircraft Integrated Meteorological Measuring System 20 Hz(AIMMS-20) has been used by the Hong Kong Observatory(HKO),China in data collection for tropical cyclone situations over the South China Sea and windshear and turbulence measurement at the Hong Kong International Airport(HKIA).This paper discusses possible methods for further enhancing the quality of the wind and temperature measurements from the *** wind measurement,the enhancement methods include:error modelling of the accelerometer(e.g.,bias offset and cross-axis rate sensitivity),global positioning system(GpS) phase lag consideration,better representation of the inertial measurement unit(IMU) velocity based on the GpS velocities and considering their location differences,consideration of the slower update of GpS velocity,and wing *** temperature measurement,the methods include the consideration of the temperature sensor response and the sensor housing *** results of typical flights using AIMMS-20 show that the accuracy of the wind and temperature data could be improved by 20%-30%.Though the discussion in the present paper is related mainly to a specific meteorological measuring system on a particular aircraft,the techniques so employed should be a useful reference for similar systems installed on other aircraft.

关键词： Airborne meteorological measurements Kalman filter Comparison with radiosonde measurement