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The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.J.Hubbard O.Hetherington D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay centre for Electronic imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(Gcrs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the Gcrs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Perfusion magnetic resonance imaging of the liver

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World Journal of Gastroenterology 2010年第13期16卷 1598-1609页

作者： Choon Hua Thng Tong San Koh David J Collins Dow Mu Koh Department of Oncologic imaging National Cancer Centre Department of Radiology Royal Marsden NHS Foundation Trust cr uk-epsrc cancer imaging centre Institute of Cancer Research

Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of antiangiogenic therapy, evaluating tumor viability after anticancer therapy or ablation, and diagnosis of liver cirrhosis and its severity. In this review, we discuss the basic concepts of perfusion MRI using tracer kinetic modeling, the common kinetic models applied for analyses, the MR scanning techniques, methods of data processing, and evidence that supports its use from published clinical and research studies. Technical standardization and further studies will help to establish and validate perfusion MRI as a clinical imaging modality.

关键词： Magnetic resonance imaging Dynamic contrast-enhanced magnetic resonance imaging Liver Tracer kinetic modeling

Fundamental error in tree-based machine learning model selection for reservoir characterisation

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 214-224页

作者： Daniel Asante Otchere centre of Excellence in Subsurface Seismic imaging and Hydrocarbon Prediction Universiti Teknologi PETRONAS32610Seri IskandarPerak Darul RidzuanMalaysia

Over the past two decades,machine learning techniques have been extensively used in predicting reservoir *** this approach has significantly contributed to the industry,selecting an appropriate model is still challenging for most *** solely on statistical metrics to select the best model for a particular problem may not always be the most effective *** study encourages researchers to incorporate data visualization in their analysis and model selection *** evaluate the suitability of different models in predicting horizontal permeability in the Volve field,wireline logs were used to train Extra-Trees,Ridge,Bagging,and XGBoost *** Random Forest feature selection technique was applied to select the relevant logs as inputs for the *** on statistical metrics,the Extra-Trees model achieved the highest test accuracy of 0.996,RMSE of 19.54 mD,and MAE of 3.18 mD,with XGBoost coming in ***,when the results were visualised,it was discovered that the XGBoost model was more suitable for the problem being *** XGBoost model was a better predictor within the sandstone interval,while the Extra-Trees model was more appropriate in non-sandstone *** this study aims to predict permeability in the reservoir interval,the XGBoost model is the most *** contrasting results demonstrate the importance of incorporating data visualisation techniques as an evaluation *** the heterogeneity of the subsurface,relying solely on statistical metrics may not be sufficient to determine which model is best suited for a particular problem.

关键词： Data visualisation Permeability Machine learning Statistical metrics

4-Nitrocatechol as a novel matrix for low-molecular-weight compounds in situ detection and imaging in biological tissues by MALDI-MSI

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Chinese Chemical Letters 2024年第6期35卷 486-490页

作者： Hualei Xu Manman Han Haiqiang Liu Liang Qin Lulu Chen Hao Hu Ran Wu Chenyu Yang Hua Guo Jinrong Li Jinxiang Fu Qichen Hao Yijun Zhou Jinchao Feng Xiaodong Wang Key Laboratory of Mass Spectrometry imaging and Metabolomics(Minzu University of China) State Ethnic Affairs CommissionBeijing 100081China College of Life and Environmental Sciences Centre for Imaging&Systems BiologyMinzu University of ChinaBeijing 100081China

Low-molecular-weight(LMW)compounds are ubiquitous in living organisms and play essential roles in biological *** direct analysis of LMW compounds in biological tissues by matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI)could provide a more comprehensive understanding of their essential ***,we evaluated 4-nitrocatechol(4-NC)as a novel positive-ion matrix for enhancing in situ detection and imaging of LMW compounds from the rat liver,brain,and germinating Chinese-yew seed by *** results showed that the 4-NC possessed remarkable features,including strong ultraviolet absorption,uniform matrix crystal,excellent chemical stability,and fewer matrix-related background *** use of 4-NC led to the successful detection of 232,218,and193 LMW compounds from the three abovementioned tissue sections,***,the use of 4-NC improved the imaging quality of LMW compounds in tissue sections through MALDI-MSI and has the potential as a matrix for MALDI tissue imaging of LMW compounds.

关键词： MALDI-MSI 4-Nitrocatechol LMW compounds In situ detection Tissue imaging

Deformable microlaser force sensing

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Light(Science & Applications) 2024年第6期13卷 1196-1209页

作者： Eleni Dalaka Joseph SHill Jonathan H.H.Booth Anna Popczyk Stefan R.Pulver Malte C.Gather Marcel Schubert centre of Biophotonics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsUK Humboldt centre for Nano-and Biophotonics Department of ChemistryUniversity of CologneKölnGermany School of Psychology and Neuroscience University of St AndrewsSt Mary’s QuadSouth StreetSt AndrewsUK Institute for Bioengineering of Catalonia BarcelonaSpain

Mechanical forces are key regulators of cellular behavior and function,affecting many fundamental biological processes such as cell migration,embryogenesis,immunological responses,and pathological *** force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in ***,current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue,reducing their application to 2D cell cultures and highly transparent biological ***,we introduce DEFORM,deformable microlaser force sensing,a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal *** is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer *** validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force,DEFORM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila *** furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution,thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis,tissue remodeling,and tumor invasion.

关键词： invasion otherwise hundreds

Light sheet microscope scanning of biointegrated microlasers for localized refractive index sensing

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Photonics Research 2024年第8期12卷 1673-1680页

作者： ROSS C.COWIE MARCEL SCHUBERT SUPA School of Physics and AstronomyUniversity of St AndrewsSt AndrewsUK Humboldt centre for Nano and Biophotonics Department of ChemistryUniversity of CologneCologneGermany

Whispering gallery mode(WGM)microlasers are highly sensitive to localized refractive index changes allowing to link their emission spectrum to various chemical,mechanical,or physical *** recently found applications in biological studies within single cells,in three-dimensional samples such as multicellular spheroids,or in ***,detailed studies of biological samples also need to account for the structural heterogeneity of tissues and live animals,therefore requiring a combination of high-resolution microscopy and laser ***,we design and construct a light sheet fluorescence microscope with a coupled spectrometer for use in microlaser studies for combined high-resolution,high-speed imaging and WGM spectral *** light sheet illumination profile and the decoupled geometry of excitation and emission hereby directly affect the lasing and sensing properties,mainly through geometric constraints and by light coupling *** demonstrate the basic working principle of microlaser spectroscopy under light sheet excitation and measure the absolute refractive index within agarose and in zebrafish tail muscle *** further analyze the light coupling conditions that lead to the occurrence of two separate oscillation *** so-called cross modes can be scanned around the entire microlaser surface,which allows to estimate a surface-averaged refractive index profile of the microlaser environment.

关键词： refractive index excitation

Electric tuning of plasmonic resonances in ultrathin gold nanoribbon arrays

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Photonics Research 2024年第8期12卷 1750-1759页

作者： ZHENXIN WANG ALEXEY VKRASAVIN CHENXINYU PAN JUNSHENG ZHENG ZHIYONG LI XIN GUO ANATOLY VZAYATS LIMIN TONG PAN WANG State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Department of Physics and London centre for Nanotechnology King’s College LondonStrandLondon WC2R 2LSUK Jiaxing Key Laboratory of Photonic Sensing&Intelligent imaging Intelligent Optics&Photonics Research CenterJiaxing Research Institute Zhejiang UniversityJiaxing 314000China

Ultrathin plasmonic nanostructures offer an unparalleled opportunity for the study of light–matter interactions at the nanoscale and realization of compact nanophotonic *** this study,we introduce an ultrathin gold nanoribbon array and demonstrate an electric approach to actively tuning its plasmonic resonance,which leveraging the extreme light confinement capability in the ultrathin plasmonic nanostructure and a robust nanoscale electro-optical effect in indium tin *** the design(to a total thickness as small as 12 nm for a 2-nmthick gold nanoribbon array),we numerically demonstrate a spectral shift in the plasmonic resonance up to 36 nm along with an approximately 16%change in the transmission at a gate voltage below 1.7 V at the wavelength of1.47μ*** work presents progress towards electric tuning of plasmonic resonances in ultrathin metallic nanostructures for various applications including surface-enhanced spectroscopy,spontaneous emission enhancement,and optical modulation.

关键词： plasmon tuning realization

The interplay of drug therapeutics and immune responses to SARS-CoV-2

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Cellular & Molecular Immunology 2024年第2期21卷 197-200页

作者： Valeria Fumagalli Matteo Iannacone Division of Immunology Transplantationand Infectious DiseasesIRCCS San Raffaele Scientific InstituteMilanItaly Vita-Salute San Raffaele University MilanItaly Experimental imaging centre IRCCS San Raffaele Scientific InstituteMilanItaly

The SARS-CoV-2 pandemic has necessitated rapid therapeutic and preventative *** vaccines form the frontline of defense,antiviral treatments such as nirmatrelvir have emerged as vital adjunctive measures,particularly for those unable or unwilling to be *** review delves into the potential influence of nirmatrelvir on enduring *** parallel,the potential of drug repurposing is explored,with bisphosphonates being examined for their possible effects against COVID-19 due to their immunomodulatory *** importance of rigorous clinical trials and careful interpretation of preliminary data is emphasized.

关键词： SARS-CoV-2 Nirmatrelvir Bisphosphonates Adaptive immunity Drug repurposing

Preface–Introduction to the Special Issue for Chinese-Russian Workshop on Biophotonics and Biomedical Optics

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 1-3页

作者： Tingting Yu Dan Zhu Valery V.Tuchin Britton Chance Center for Biomedical Photonics-MoE Key Laboratory for Biomedical Photonics Advanced Biomedical Imaging FacilityWuhan National Laboratory for Optoelectronics–Advanced Biomedical Imaging FacilityHuazhong University of Science and TechnologyWuhan 430074China Department of Optics and Biophotonics Science Medical CenterSaratov State UniversitySaratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and ControlFRC“Saratov Scientic Centre of the Russian Academy of Sciences”Saratov 410028Russia Laboratory of Laser Molecular imaging and Machine Learning Tomsk State UniversityTomsk 634050Russia

The Chinese-Russian Workshop on Biophotonics and Biomedical Optics 2023 was held online twice on 18–21 September and 25–26 September *** bilateral workshop brought together both Russian and Chinese scientists,engineers,and clinical researchers from a variety of disciplines engaged in applying optical science,photonics,and imaging technologies to problems in biology and *** the workshops,two plenary lectures and twenty invited presentations were *** special issue selects some papers from both Russian and Chinese sides,consisting of one review and seven original research articles.

关键词： Russian photonics Biomedical