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Refill friction stir spot welding (RFSSW): a review of processing, similar/dissimilar materials joining, mechanical properties and fracture mechanism

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Journal of Iron and Steel Research International 2024年第8期31卷 1825-1839页

作者： Yun-qiang Zhao Hao-kun Yang Aloshyn Andriia Hong-hang lo Jia-xin Li Guangdong Provincial Key Laboratory of Advanced Welding Technology China-Ukraine Institute of WeldingGuangdong Academy of SciencesGuangzhou 510000GuangdongChina Smart Manufacturing Division Hong Kong Productivity CouncilHong Kong 999077China E.O.Paton Electric Welding Institute of National Academy of Sciences of Ukraine Kiev 01001KievanUkraine

Refill friction stir spot welding(RFSSW)provides a novel method to join similar and/or dissimilar metallic materials without a key-hole in the center of the *** the key-hole free characterization,the similar/dissimilar RFSSW joint exhibits remarkable and endurable characteristics,including high shear strength,long fatigue life,and strong corrosion *** the meanwhile,as the key-hole free joint has different microstructures compared with conventional friction stir spot welding,thus the RFSSW joint shall possess different shear and fatigue fracture mechanisms,which needs further *** explore the underlying failure mechanism,the similar/dissimilar metallic material joining parameters and pre-treatment,mechanical properties,as well as fracture mechanisms under this novel technology will be *** details,the welding tool design,welding parameters setting,and the influence of processing on the lap shear and fatigue properties,as well as the corrosion resistance will be mainly ***,the roadmap of RFFSW is also discussed.

关键词： Refill friction stir spot welding Processing Mechanism Similar materials joining Dissimilar materials joining Microstructure Mechanical property Fracture mechanism

How Can Practitioners Support Citizen Volunteers in Disaster Risk Reduction?Insight from“Good and Ready”in Aotearoa New Zealand

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International Journal of Disaster Risk Science 2024年第3期15卷 374-387页

作者： loïc Le Dé Steve Ronoh Ei Mon Thinn Kyu Brigitte Rive School of Public Health and Interdisciplinary Studies Auckland University of TechnologyAuckland2025New Zealand Pacific Health Research Centre Auckland University of TechnologyAuckland2025New Zealand New Zealand Red Cross Auckland2241New Zealand

Global and national policy frameworks emphasize the importance of people's participation and volunteers'role in disaster risk *** research has extensively focused on volunteers in disaster response and recovery,less attention has been paid on how organizations involved in disaster risk management can support volunteers in leading and coordinating communitybased disaster risk *** 2019,the New Zealand Red Cross piloted the Good and Ready initiative in Auckland,Aotearoa New Zealand,with the objective to empower local people in resilience building with a focus on volunteers and community *** research examined the positive and negative outcomes of Good and Ready and investigated volunteers'experiences in the disaster resilience *** involved the codesign of a questionnaire-based survey using participatory methods with Good and Ready volunteers,the dissemination of the survey to gather volunteers'viewpoints,and a focus group discussion with participatory activities with Red Cross *** findings highlight that a key challenge lies in finding a balance between a program that provides flexibility to address contextual issues and fosters communities'ownership,versus a prescriptive and standardized approach that leaves little room for creativity and *** pinpoints that supporting volunteers with technical training is critical but that soft skills training such as coordinating,communicating,or facilitating activities at the local level are *** concludes that the sustainability of Good and Ready requires understanding and meeting volunteers'motivations and expectations and that enhancing partnerships with local emergency management agencies would strengthen the program.

关键词： Community-based approach Disaster risk reduction New Zealand Participation Volunteers

The bending of light ray and unphysical solutions in general relativity

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Chinese Physics B 2004年第2期13卷 159-167页

作者： C.Y.lo AppliedandPureResearchInstitute 17NewcastleDriveNashuaNH03060USA

In general relativity, according to Einstein, a gauge is related to the time dilation and the space contractions,and thus a physically realizable gauge should be unique for a given frame of reference. Since more than one metric solution for the same frame can produce the same deflection angle, this means that an invalid space-time metric can produce the correct deflection angle for a light ray. To demonstrate this with an unambiguous example, we consider a new extreme case that there is no space contraction in the radius direction while the conditions of asymptotic flatness and the requirement for gravitational red shifts are satisfied. This solution has a distinct characteristic of 'space expansion' in the other directions. Nevertheless, it turns out that, in spite of requiring far more subtle calculations, the resulting deflection angle of a light ray is the same. An interesting property of this new solution is that its event horizon corresponds to an arbitrary integral constant. Thus, this calculation demonstrates beyond doubt that an unphysical solution can produce the correct first-order approximation of light bending. This makes it clear that there is a main difference between local effects such as the gravitational red shifts and the local light speeds, which are not gauge invariant, and integrated effects such as the bending of light, which can be (restricted) gauge invariant.

关键词： Einstein's equivalence principle Euclidean-like structure bending of light black hole space expansion

Hepatitis C virus:Virology,diagnosis and treatment

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World Journal of Hepatology 2015年第10期7卷 1377-1389页

作者： Hui-Chun Li Shih-Yen lo Department of Biochemistry Tzu Chi University Department of Laboratory Medicine and Biotechnology Tzu Chi University Department of Laboratory Medicine Buddhist Tzu Chi General Hospital

More than twenty years of study has provided a better understanding of hepatitis C virus(HCV) life cycle,including the general properties of viral RNA and proteins. This effort facilitates the development of sensitive diagnostic tools and effective antiviraltreatments. At present,serologic screening test is recommended to perform on individuals in the high risk groups and nucleic acid tests are recommended to confirm the active HCV infections. Quantization and genotyping of HCV RNAs are important to determine the optimal duration of anti-viral therapy and predict the likelihood of response. In the early 2000 s,pegylated interferon plus ribavirin became the standard antiHCV treatment. However,this therapy is not ideal. To 2014,boceprevir,telaprevir,simeprevir,sofosbuvir and Harvoni are approved by Food and Drug Administration for the treat of HCV infections. It is likely that the new all-oral,interferon-free,pan-genotyping anti-HCV therapy will be available within the next few years. Majority of HCV infections will be cured by these antiviral treatments. However,not all patients are expected to be cured due to viral resistance and the high cost of antiviral treatments. Thus,an efficient prophylactic vaccine will be the next challenge in the fight against HCV infection.

关键词： Hepatitis C virus Diagnosis Treatment Hepatocellular carcinoma Nucleic acid test Enzymeimmunoassay Interferon Direct acting antivirals Hosttargetedagents Sofosbuvir

Taxonomic and environmental implication of pedotechnique in large scale farming

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International Soil and Water Conservation Research 2016年第2期4卷 137-141页

作者： Carmelo Dazzi Giuseppe lo Papa Department of Agricultural and Forest Sciences University of PalermoItaly

Human activities that involve deep modifications of the soils and a substantial deterioration of their features are numerous and very *** activities are considered as pedotechniques and,in largescale farming,are used only under the boost of significant economic *** these last decades,the pedotechniques used to tailor soils suitable for table vine cultivation in the Acate valley(Sicily,Italy),not only led to objective difficulties in the classification of these deeply transformed soils but also,to several environmental *** this work after considering the pedotechniques used in tailoring suitable soil for table vine cultivation,we propose to introduce Anthrosols as a new taxonomic soil Order in Soil Taxonomy stressing that a correct soil classification of these deeply modified soils allow for a correct understanding of their features and of the environmental hazards that their management could originate.

关键词： Pedotechniques Soil classification Quality of the environment

An elliptical blade is not a true ellipse,but a superellipse–Evidence from two Michelia species

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Journal of Forestry Research 2022年第4期33卷 1341-1348页

作者： Yuping Li Karl JNiklas Johan Gielis Ülo Niinemets Julian Schrader Rong Wang Peijian Shi College of Horticulture Jinling Institute of TechnologyNanjing 210038People’s Republic of China Bamboo Research Institute Nanjing Forestry UniversityNanjing 210037People’s Republic of China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium Institute of Agricultural and Environmental Sciences Estonian University of Life Sciences51006 TartuEstonia Estonian Academy of Sciences 10130 TallinnEstonia Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia Biodiversity Macroecology and BiogeographyUniversity of Göttingen37077 GöttingenGermany

The shape of leaf laminae exhibits considerable diversity and complexity that reflects adaptations to environmental factors such as ambient light and precipitation as well as phyletic *** leaves appear to be elliptical which may represent a‘default’developmental ***,whether their geometry truly conforms to the ellipse equation(EE),i.e.,(x/a)^(2)+(y/b)^(2)=1,remains *** alternative is described by the superellipse equation(SE),a generalized version of EE,i.e.,|x/a|^(n)+|y/b|^(n)=*** test the efficacy of EE versus SE to describe leaf geometry,the leaf shapes of two Michelia species(i.e.,*** ***,and ***),were investigated using 60 leaves from each *** shows that the majority of leaves(118 out of 120)had adjusted root-mean-square errors of<0.05 for the nonlinear fitting of SE to leaf geometry,i.e.,the mean absolute deviation from the polar point to leaf marginal points was smaller than 5%of the radius of a hypothesized circle with its area equaling leaf *** estimates of n for the two species were<2,indicating that all sampled leaves conformed to SE and not to *** study confirms the existence of SE in leaves,linking this to its potential functional advantages,particularly the possible influence of leaf shape on hydraulic conductance.

关键词： Bilateral symmetry Leaf ellipticalness index Leaf laminae Leaf roundness index Magnoliaceae

Carbon nanotube supported PtOx nanoparticles with hybrid chemical states for efficient hydrogen evolution

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Journal of Energy Chemistry 2021年第7期30卷 364-369页

作者： Kun Feng Hechuang Zheng Duo Zhang Guotao Yuan lo-Yueh Chang Yufeng Chen Jun Zhong Institute of Functional Nano and Soft Materials Laboratory(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123JiangsuChina State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123JiangsuChina

Efficient electrocatalysts for hydrogen evolution reaction(HER) in alkaline solution are highly required for water *** we design an ultra-small PtOx nanoparticle with hybrid Pt chemical states on carbon nanotubes as highly efficient alkaline HER catalyst,which shows a low overpotential of 19.4 mV at 10 mA cm^(-2),a high mass activity of 5.56 A mg_(Pt)^(-1) at 0.1 V, and a stable durability for at least 20 *** HER performance is better than that of the benchmark 20 wt% Pt/C while the Pt content in the catalyst is only about one tenth of that in Pt/*** also represents one of the best catalysts ever reported for HER in alkaline *** radiation X-ray absorption spectroscopy reveals that the efficient and stable alkaline HER performance can be attributed to the favorable design of hybrid chemical states of Pt with carbon nanotubes,which exhibits abundant surface Pt-O as active catalytic sites and forms stable Pt-C interfacial interaction to both anchor the NPs and improve the synergistic effect between catalyst and substrate.

关键词： Electrochemical HER Carbon nanotubes Hybrid chemical states Ultra-small nanoparticle Interfacial interaction

Smart phone apps every ophthalmologist should know about

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International Journal of Ophthalmology(English edition) 2020年第8期13卷 1329-1333页

作者： Ming Yang Amy Cheuk Yin lo Wai Ching Lam Department of Ophthalmology Li Ka Shing Faculty of Medicinethe University of Hong KongHong Kong Special Administrative Region 999077China

We are living in a mobile world,where the number of medical apps is surging in recent *** 320000 healthcare apps are now available as shown in the latest *** major function and potential of these apps vary,from assisting the learning and practice of clinicians as well as achieving better outcomes of patients to preventing eye diseases through the education of healthy ***,based on the various features,ophthalmology apps nowadays contain a wide range of subjects and focus on dif ferent stakeholder s in the ophthalmic practice,including but not limited to doctors,patients,and ***,we review special and advanced apps that ophthalmologists will find useful in their clinical practice.

关键词： applications healthcare clinic ophthalmology ophthalmologist

An adaptive microscope for the imaging of biological surfaces

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Light(Science & Applications) 2021年第11期10卷 2195-2206页

作者： Faris Abouakil Huicheng Meng Marie-Anne Burcklen Herve Rigneault Frederic Galland loïc LeGoff Aix Marseille Univ CNRSCentrale MarseilleInstitut FresnelTuring Center for Living SystemsMarseilleFrance

Scanning fluorescence microscopes are now able to image large biological samples at high spatial and temporal *** comes at the expense of an increased light dose which is detrimental to fluorophore stability and cell *** highly reduce the light dose,we designed an adaptive scanning fluorescence microscope with a scanning scheme optimized for the unsupervised imaging of cell sheets,which underly the shape of many embryos and *** surface of the tissue is first delineated from the acquisition of a very small subset(~0.1%)of sample space,using a robust estimation *** alternative scanning strategies are then proposed to image the tissue with an improved photon budget,without loss in *** first strategy consists in scanning only a thin shell around the estimated surface of interest,allowing high reduction of light dose when the tissue is *** second strategy applies when structures of interest lie at the cell periphery(*** junctions).An iterative approach is then used to propagate scanning along cell *** demonstrate the benefit of our approach imaging live epithelia from Drosophila *** the examples shown,both approaches yield more than a 20-fold reduction in light dose-and up to more than 80-fold-compared to a full scan of the *** smart-scanning strategies can be easily implemented on most scanning fluorescent imaging *** dramatic reduction in light exposure of the sample should allow prolonged imaging of the live processes under investigation.

关键词： image curved smart