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Evaluating metallic artefact of biodegradable magnesium-based implants in magnetic resonance imaging

bioactive Materials 2022年第9期7卷 382-391页

作者： jonathan Espiritu Mostafa berangi Christina Yiannakou Eduarda Silva roberto Francischello Andre Kuehne Thoralf Niendorf Soren Konneker regine Willumeit-romer Jan-Marten Seitz Syntellix AG HannoverGermany MrI.TOOLS GmbH BerlinGermany Charit´e-Universitatsmedizin berlin Corporate Member of Freie Universitat Berlin and Humboldt Universitat zu BerlinBerlinGermany berlin Ultrahigh Field Facility(b.U.F.F.) Max-Delbrueck Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany Hannover Medical School HannoverGermany Institute of Clinical Physiology National Research CouncilPisaItaly Chemistry and Industrial Chemistry Department Universita di PisaVia Moruzzi 13PisaItaly Fondazione Toscana Gabriele Monasterio Via Moruzzi 1PisaItaly Institute for Materials research Helmholtz Zentrum HereonGeesthachtGermany

Magnesium(Mg)implants have shown to cause image artefacts or distortions in magnetic resonance imaging(MrI).Yet,there is a lack of information on how the degradation of Mg-based implants influences the image quality of MrI *** this study,Mg-based implants are analysed in vitro,ex vivo,and in the clinical setting for various magnetic field strengths with the aim to quantify metallic artefact *** vitro corroded Mg-based screws and a titanium(Ti)equivalent were imaged according to the ASTM ***-based and Ti pins were also implanted into rat femurs for different time points and scanned to provide insights on the influence of soft and hard tissue on metallic ***,MrI data of patients with scaphoid fractures treated with CE-approved Mg-based compression screws(MAGNEZIX®)were analysed at various time points *** artefact production of the Mg-based material decreased as implant material degraded in all *** worst-case imaging scenario was determined to be when the imaging plane was selected to be perpendicular to the implant ***,the Mg-based implant outperformed the Ti equivalent in all experiments by producing lower metallic artefact(prates that Mg-based implants generate significantly lower metallic distortion in MrI when compared to *** positive findings suggest and support further research into the application of Mg-based implants including post-operative care facilitated by MrI monitoring of degradation kinetics and bone/tissue healing processes.

关键词： Magnetic resonance imaging Magnesium biodegradable implants Medical imaging Translational medicine

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可见光催化C(sp^3)-C(sp^3)键的构筑

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化学进展 2019年第4期31卷 505-515页

作者：易享炎黄菲 jonathan b.baell 黄和于杨南京工业大学药学院南京211816 南京工业大学环境科学与工程学院南京211816

本文对近年来可见光催化构筑C(sp^3)-C(sp^3)键的国内外最新研究成果进行概述,着重阐述了各类催化的催化体系、反应机理及在合成生物活性分子或药物分子方面的应用。在可见光催化的反应体系中引入过渡金属或手性催化剂,构建新颖的协同... 详细信息

本文对近年来可见光催化构筑C(sp^3)-C(sp^3)键的国内外最新研究成果进行概述,着重阐述了各类催化的催化体系、反应机理及在合成生物活性分子或药物分子方面的应用。在可见光催化的反应体系中引入过渡金属或手性催化剂,构建新颖的协同催化体系,可以实现在温和的条件下对C—C键构筑的精确控制,对于手性药物的设计、开发具有重要的意义。最后,对未来可见光催化构筑C—C键的发展进行展望。

关键词：可见光催化 C—C键协同催化不对称催化

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Investigation of a ship resonance through numerical simulation

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Journal of Hydrodynamics 2020年第5期32卷 969-983页

作者： S.S.Kianejad Hossein Enshaei jonathan Duffy Nazanin Ansarifard Australian Maritime College University of TasmaniaLauncestonAustralia

Understanding dynamic stability of a ship on a resonance frequency is important because comparatively smaller external forces and moments generate larger *** roll motion is most susceptible because of smaller restoring *** studies related to the failure modes such as parametric roll and dead ship condition,identified by second generation of intact stability criteria(SGISC)are performed at a resonance ***,the nature of resonance,where the model experiences an incremental roll motion,has not been well *** this study,nonlinear unsteady computational fluid dynamics(CFD)simulations were conducted to investigate the resonance phenomenon using a containership under a sinusoidal roll exciting *** capture the complexity of the phenomenon,simulations were conducted over a range of frequencies to cover the resonance frequency including lower and higher *** addition to the resonance frequency,the phase shift between roll exciting moment and roll angle,as well as the phase difference between acceleration and roll angle,were found to have significant effects on the occurrence of resonance.

关键词： resonance harmonic excited roll motion natural frequency phase shift phase difference

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remodeling of the plasma for sperm-egg recognition： proteins membrane in preparation roles of acrosomal

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Asian Journal of Andrology 2015年第4期17卷 574-582页

作者： Nongnuj Tanphaichitr Kessiri Kongmanas Hathairat Kruevaisayawan Arpornrad Saewu Clarissa Sugeng Jason Fernandes Puneet Souda jonathan b Angel Kym F Faull r John Aitken Julian Whitelegge Daniel Hardy Trish berger Mark baker Chronic Disease Program Ottawa Hospital ResearchInstitute Ottawa Ontario Canada Department ofObstetrics and Gynaecology University of OttawaOntario Canada Department of biochemistry Microbiology and Immunology University of OttawaOntario Canada Department of Anatomy Faculty ofMedical Sciences Naresuan University PhitsanulokThailand Division of Infectious Diseases OttawaHospital - General Campus Ottawa Ontario Canada Pasarow Mass Spectrometry Laboratory Universityof California Los Angeles California USA TheArC Centre of Excellence in biotechnology andDevelopment School of Environmental and LifeSciences University of Newcastle Callaghan NewSouth Wales Australia Department of Cell biologyand biochemistry Health Sciences Center Texas TechUniversity Texas USA Department of Animal ScienceUniversity of California Davis California USA

The interaction of sperm with the egg＇s extracellular matrix, the zona pellucida （ZP） is the first step of the union between male and female gametes. The molecular mechanisms of this process have been studied for the past six decades with the results obtained being both interesting and confusing. In this article, we describe our recent work, which attempts to address two lines of questions from previous studies. First, because there are numerous ZP binding proteins reported byvarious researchers, how do these proteins act together in sperm-ZP interaction？ Second, why do a number of acrosomal proteins have ZP affinity？ Are they involved mainly in the initial sperm-ZP binding or rather in anchoring acrosome reacting/reacted spermatozoa to the ZP？ Our studies reveal that a number of ZP binding proteins and chaperones, extracted from the anterior sperm head plasma membrane, coexist as high molecular weight （HMW） complexes, and that these complexes in capacitated spermatozoa have preferential ability to bind to the ZP. Zonadhesin （ZAN）, known as an acrosomal protein with ZP affinity, is one of these proteins in the HMW complexes. Immunoprecipitation indicates that ZAN interacts with other acrosomal proteins, proacrosin/acrosin and sp32 （ACrbP）, also present in the HMW complexes. Immunodetection of ZAN and proacrosin/acrosin on spermatozoa further indicates that both proteins traffic to the sperm head surface during capacitation where the sperm acrosomal matrix is still intact, and therefore they are likely involved in the initial sperm-ZP binding step.

关键词： SPErM CAPACITATION ANDSPErM-ZONA PELLUCIDAINTErACTION- bACKGrOUND ANDCONFUSION IN THE FIELDS

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 28-40页

作者： Daniel T.Payne Mandeep KChahal Vaclav brezina Whitney A.Webre Katsuhiko Ariga Francis D’Souza Jan Labuta jonathan P.Hill WPI Center for Materials Nanoarchitectonics National Institute for Materials ScienceIbaraki 305-0044Japan Department of Macromolecular Physics Faculty of Mathematics and PhysicsCharles University18000 PragueCzech Republic Department of Chemistry University of North TexasDentonTX 76203USA Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of TokyoChiba 277-8561Japan

Chiral 1,1’-binaphthyl-linked diporphyrin‘tweezers’(r)-1/(S)-1 and the corresponding zinc(II)complexes(r)-2/(S)-2 were prepared as chiral host molecules,and their utility for chiral analyses(especially enantiomeric excess(ee)determinations)were ***(1-n-dodecyl)porphyrins were used for the first time as the interacting *** capabilities of the diporphyrin tweezers were investigated by titrations with(r,r)-and(S,S)-cyclohexane-1,2-diamine(CHDA).The host molecules could be used as multichannel probes of ee by using UVvis,circular dichroism(CD),fluorescence emission and 1H nuclear magnetic resonance(1 H-NMr)*** configurations could also be differentiated using CD or 1HNMr *** three optical techniques give good resolution of ee with reasonable sensitivity considering the low concentrations used(ca.10^-6 mol·L^-1).The ee determination of CHDA enantiomers using NMr spectroscopy is also possible because of the reasonably well separated resonances in the case of(r,r)-and(S,S)-***-metallated(r)-1/(S)-1 hosts could not be used to detect chiral information in a strongly acidic chiral *** work demonstrates the utility of 1,1’-binapthyllinked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer chirality enantiomeric excess CD fluorescence

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Soil microbial biomass and population in response to seasonal variation and age in Gmelina arborea plantations in south-western Nigeria

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Journal of Forestry research 2012年第2期23卷 253-260页

作者： jonathan C. Onyekwelu Department of Forestry and Wood Technology Federal University of Technology Akure P.M.B. 704 Akure Nigeria

We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （Mb-C） and nitrogen （Mb-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean Mb-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. bacteria populations and Mb-N showed similar increasing trends. Correlations between Mb-C, Mb-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.

关键词： Gmelina arborea plantation development seasonal variation microbe population microbial biomass sustainability Nigeria

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Development of the DayCent-Photo model and integration of variable photosynthetic capacity

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Frontiers of Earth Science 2018年第4期12卷 765-778页

作者： jonathan r.STrAUbE Maosi CHEN William J.PArTON Shinichi ASSO Yan-An LIU Dennis S.OJIMA Wei GAO USDA UV-b Monitoring and research Program Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsCO 80521USA Natural resource Ecology Laboratory.Colorado State University Fort CollinsCO 80523USA Key Laboratory of Geographic Information Science (Ministry of Education) East China Normal UniversityShanghai 200241China School of Geographic Sciences East China Normal UniversityShanghai 200241China ECNU-CSU Joint research Institute for New Energy and the Environment Shanghai 200062China Department of Ecosystem Science and Sustainability Colorado State UniversityFort CollinsCO 80523USA

We integrated a photosynthetic sub-model into the daily Century model (DayCent) to improve the estimations of seasonal changes in carbon fluxes at the Niwot ridge LTEr site and the Harvard forest LTEr site (DayCent-Photo). The photosynthetic sub-model, adapted from the SIPNET/PnET family of models, includes solar radiation and vapor pressure deficit controls on production, as well as temperature and water stress terms. A key feature we added to the base photosynthetic equations is the addition of a variable maximum net photosynthetic rate (Amax). We optimized the parameters controlling photosynthesis using a variation of the Metropolis-Hastings algorithm along with data-assimilation techniques. The model was optimized and validated against observed net ecosystem exchange (NEE) and estimated gross primary production (GPP) and ecosystem respiration (rESP) values for AmeriFlux sites at Niwot ridge and Harvard forest. The inclusion of a variable Amax rate greatly improved model performance (NEE rMSE = 0.63 gC·m–2, AIC = 2099) versus a version with a single Amax parameter (NEE rMSE = 0.74 gC·m–2, AIC = 3724). DayCent-Photo was able to capture the inter-annual and seasonal flux patterns for NEE, GPP, ecosystem respiration (rESP), and daily actual evapotranspiration (AET), but tended to overestimate yearly NEE uptake. The DayCent-Photo model has been successfully set up to simulate daily NEE, GPP, rESP, and AET for deciduous forest, conifer forests, and grassland systems in the US using AmeriFlux data sets and has recently been improved to include the impact of UV radiation surface litter decay (DayCent-UV). The simulated influence of a variable Amax rate suggests a need for further studies on the process controls affecting the seasonal photosynthetic rates. The results for all of the forest and grassland sites show that maximum Amax values occurs early during the growing period and taper off toward the end of the growing season.

关键词： DayCent-Photo model seasonal maximum net photosynthetic rate net ecosystem exchange gross primary production UV radiation

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COOrDINATION OF INTErNATIONAL bEDLOAD rESEArCH

COORDINATION OF INTERNATIONAL BEDLOAD RESEARCH

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第九次河流泥沙国际学术大会

作者： John r.GrAY jonathan b.LArONNE U.S. Geological Survey Reston Virginia U.S.A. 20192. The ben Gurion University of the Negev Beer Sheva 84105 Israel.

＜正＞The state of the science of bedload research and monitoring in the last quarter century has progressed at a much slower rate than that for suspended sediment due to a number of constraints. Most traditional devices still entail routine collection and subsequent analyses of physical samples. The amount and reliability of the bedload data remain limited by the characteristics of the collecting instrument, vagaries associated with manual deployment, a lack of temporal continuity in measurements, and hydraulic and bed conditions. Acceptable and quantifiably accurate measurement of bedload discharge at discrete time intervals, let alone as a time series, is rarely an attainable goal. The accuracy of equations for estimating bedload transport, predicated on data reliability, remains unquantifiable for most conditions. On-going research on bedload-measurement instruments and measuring techniques has been taking place on an ad hoc basis within and between various countries, with little coordination among researchers. bedload studies often lack adequate funding and adequate local or institutional scientific support. We propose establishing a bedload research International Cooperative （brIC） to address some of these constraints. The brIC would be by, for, and responsive to the international bedload research and monitoring community. It would provide an international focal point for bedload research, methods development and data sharing. Membership would be free, as would be acquisition of brIC data. Information compiled and disseminated as part of the brIC would enable coordination of research to fill critical gaps in our knowledge of bedload processes and measurement techniques. The concept of the brIC is evolving;suggestions are sought as the concept matures.

关键词： bedload bedload monitoring bedload research International collaboration

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Aminoflavone upregulates putative tumor suppressor mir-125b-2-3p to inhibit luminal A breast cancer stem cell-like properties

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Precision Clinical Medicine 2022年第2期5卷 72-86页

作者： Nicole Mavingire Petreena Campbell Tiantian Liu jonathan Wooten Salma Khan Xin Chen Jason Matthews Charles Wang Eileen brantley Department of basic Sciences Loma Linda University School of MedicineLoma LindaCA 92350USA Center for Genomics Loma Linda University School of MedicineLoma LindaCA 92350USA Center for Health Disparities and Molecular Medicine Loma Linda University School of MedicineLoma LindaCA 92350USA Department of Nutrition University of OsloOslo 0372Norway Department of Pharmacology and Toxicology University of TorontoTorontoOntario M5S 1A8Canada Frederick National Laboratory for Cancer research PO Box BBldg.432Room 232 FrederickMD 21702-1201USA

Metastatic breast cancer is incurable and often due to breast cancer stem cell(CSC)-mediated *** previously determined that the aryl hydrocarbon receptor(Ahr)agonist aminoflavone(AF)inhibits the expression of the CSC biomarkerα6-integrin(ITGA6)to disrupt the formation of luminal(hormone receptor-positive)mammospheres(3D breast cancer spheroids).In this study,we performed mirNA-sequencing analysis of luminal A MCF-7 mammospheres treated with AF to gain further insight into the mechanism of AF-mediated anti-cancer and anti-breast CSC *** significantly induced the expression of>70 microrNAs(mirNAs)including mir125b-2–3p,a predicted stemness gene ***-mediated mir125b-2–3p induction was validated in MCF-7 mammospheres and ***125b-2–3p levels were low in breast cancer tissues irrespective of subtype compared to normal breast *** mir125b-2–3p levels were low in MCF-7 cells,they were much lower in AHr100 cells(MCF-7 cells made unresponsive to Ahr agonists).The mir125b-2–3p mimic decreased,while the antagomir125b-2–3p increased the expression of stemness genes ITGA6 and SOX2 in MCF-7 *** MCF-7 mammospheres,the mir125b-2–3p mimic decreased only ITGA6 expression although the antagomir125b-2–3p increased ITGA6,SOX2 and MYC ***125b-2–3p reversed AF-mediated suppression of *** mir125b-2–3p mimic decreased proliferation,migration,and mammosphere formation while the antagomir125b-2–3p increased proliferation and mammosphere formation in MCF-7 *** mir125b-2–3p mimic also inhibited proliferation,mammosphere formation,and migration in AHr100 *** induced Ahr-and mir125b2-3p-dependent anti-proliferation,anti-migration,and mammosphere disruption in MCF-7 *** findings suggest that mir125b-2–3p is a tumor suppressor and AF upregulates mir125b-2–3p to disrupt mammospheres via mechanisms that rely at least partially on Ahr in luminal A breast cancer cells.

关键词： breast cancer cancer stem cells therapeutic targeting mir125b-2-3p aminoflavone aryl hydrocarbon receptor mammospheres

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Secretions from hypochlorous acid-treated tumor cells delivered in a melittin hydrogel potentiate cancer immunotherapy

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bioactive Materials 2022年第3期7卷 541-553页

作者： Yuhan Zhou Ting Ye Chengzhi Ye Chao Wan Siyue Yuan Yushuai Liu Tianyu Li Fagang Jiang jonathan F.Lovell Honglin Jin Jing Chen Cancer Center Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022PR China Department of Pediatrics Renmin Hospital of Wuhan UniversityWuhan430060PR China Department of Ophthalmology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022PR China Department of biomedical Engineering University at BuffaloState University of New York.BuffaloNew York14260USA College of biomedicine and Health and College of Life Science and Technology Huazhong Agricultural UniversityWuhan430070China

Autologous tumor cells and cell-derived secretions(CDS)can induce antitumor immune *** conditions in which cells are cultured and treated impact CDS,and cellular insults alter their composition and *** this study,we generated CDS from tumor cells exposed to normal culture conditions,hypoxia,cisplatin,radiotherapy,photodynamic therapy,or hypochlorous acid(HOCl).In vitro HOCl-CDS showed the strongest stimulatory effects on dendritic cells and macrophages compared to CDS generated by hypoxia,cisplatin,radiotherapy or photodynamic *** improve HOCl-CDS activity at the tumor site,we loaded HOCl-CDS into a melittin-encapsulated hydrogel *** injected intratumorally,the HOCl-CDS hydrogel promoted tumor cell death,cytotoxic T lymphocyte infiltration,and tumor-associated macrophage reprogramming towards an M1 *** hydrogel inhibited tumor growth and prolonged the survival of mice bearing b16-F10 ***,hydrogel-delivered HOCl-CDS augmented the antitumor effects of immune checkpoint *** results underscore the importance of the CDS generation method and delivery approach for improving cancer immunotherapy.

关键词： Cancer immunotherapy Hydrogel Melittin Anti-PD-1 Cell-derived secretions

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