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Spatial heterogeneity of oxygenation and haemodynamics in breast cancer resolved in vivo by conical multispectral optoacoustic mesoscopy

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Light(Science & Applications) 2020年第1期9卷 1455-1469页

作者： Jiao Li Andrei Chekkoury Jaya Prakash Sarah Glasl Paul Vetschera Benno Koberstein-Schwarz Ivan Olefir Vipul Gujrati murad omar Vasilis Ntziachristos School of Precision Instruments and Optoelectronics Engineering Tianjin UniversityNo.92Weijin RoadNankai District300072 TianjinChina Institute of Biological and Medical Imaging Helmholtz Zentrum MunchenIngolstadter Landstr.1D-85764 NeuherbergGermany Chair of Biological Imaging TranslaTUMTechnische Universitat MunchenIsmaningerstr.22D-81675 MunichGermany Department of Instrumentation and Applied Physics Indian Institute of Science BangaloreCV Raman RdBengaluru 560012 KarnatakaIndia

The characteristics of tumour development and metastasis relate not only to genomic heterogeneity but also to spatial heterogeneity,associated with variations in the intratumoural arrangement of cell populations,vascular morphology and oxygen and nutrient *** optical(photonic)microscopy is commonly employed to visualize the tumour microenvironment,it assesses only a few hundred cubic microns of ***,it is not suitable for investigating biological processes at the level of the entire tumour,which can be at least four orders of magnitude *** this study,we aimed to extend optical visualization and resolve spatial heterogeneity throughout the entire tumour *** developed an optoacoustic(photoacoustic)mesoscope adapted to solid tumour imaging and,in a pilot study,offer the first insights into cancer optical contrast heterogeneity in vivo at an unprecedented resolution of<50μm throughout the entire tumour *** spectral methods,we resolve unknown patterns of oxygenation,vasculature and perfusion in three types of breast cancer and showcase different levels of structural and functional *** our knowledge,these results are the most detailed insights of optical signatures reported throughout entire tumours in vivo,and they position optoacoustic mesoscopy as a unique investigational tool linking microscopic and macroscopic observations.

关键词： insight arrangement linking

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Optoacoustic microscopy at multiple discrete frequencies

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Light(Science & Applications) 2018年第1期7卷 7-18页

作者： Stephan Kellnberger Dominik Soliman George J.Tserevelakis Markus Seeger Hong Yang Angelos Karlas Ludwig Prade murad omar Vasilis Ntziachristos Institute of Biological and Medical Imaging(IBMI) Helmholtz Zentrum MunchenIngolstadter Landstr.185764 NeuherbergGermany Chair of Biological Imaging(CBI)and Center for Translational Cancer Research(TranslaTUM) Technical University MunichEinsteinstrase 2581675 MunchenGermany Cardiovascular Research Center Cardiology DivisionMassachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA Xidian University South Taibai Road 02710071 Xi’anShaanxiChina

Optoacoustic(photoacoustic)sensing employs illumination of transient energy and is typically implemented in the time domain using nanosecond photon ***,the generation of high-energy short photon pulses requires complex laser technology that imposes a low pulse repetition frequency(PRF)and limits the number of wavelengths that are concurrently available for spectral *** avoid the limitations of working in the time domain,we have developed frequency-domain optoacoustic microscopy(FDOM),in which light intensity is modulated at multiple discrete *** integrated FDOM into a hybrid system with multiphoton microscopy,and we examine the relationship between image formation and modulation frequency,showcase high-fidelity images with increasing numbers of modulation frequencies from phantoms and in vivo,and identify a redundancy in optoacoustic measurements performed at multiple *** demonstrate that due to high repetition rates,FDOM achieves signal-to-noise ratios similar to those obtained by time-domain methods,using commonly available laser ***,we experimentally confirm various advantages of the frequency-domain implementation at discrete modulation frequencies,including concurrent illumination at two wavelengths that are carried out at different modulation frequencies as well as flow measurements in microfluidic chips and in vivo based on the optoacoustic Doppler ***,we discuss how FDOM redefines possibilities for optoacoustic imaging by capitalizing on the advantages of working in the frequency domain.

关键词： repetition illumination multiple

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Opening a window to skin biomarkers for diabetes stage with optoacoustic mesoscopy

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Light(Science & Applications) 2023年第11期12卷 2335-2349页

作者： Hailong He Nikolina-Alexia Fasoula Angelos Karlas murad omar Juan Aguirre Jessica Lutz Michael Kallmayer Martin Fuchtenbusch Hans-Henning Eckstein Annette Ziegler Vasilis Ntziachristos Institute of Biological and Medical Imaging Helmholtz Zentrum MunchenNeuherbergGermany Chair of Biological Imaging at the Central Institute for Translational Cancer Research(TranslaTUM) School of MedicineTechnical University of MunichMunichGermany Department for Vascular and Endovascular Surgery Klinikum rechts der IsarTechnical University of Munich(TUM)MunichGermany DZHK(German Centre for Cardiovascular Research) partner site Munich Heart AllianceMunichGermany Diabetes Center at Marienplatz MunichGermany Forschergruppe Diabetes e.V. Helmholtz Zentrum MunchenNeuherbergGermany Institute of Diabetes Research Helmholtz Zentrum MunchenNeuherbergGermany

Being the largest and most accessible organ of the human body,the skin could offer a window to diabetes-related complications on the ***,skin microvasculature is typically assessed by histological analysis,which is not suited for applications to large populations or longitudinal *** introduce ultra-wideband rasterscan optoacoustic mesoscopy(RSOM)for precise,non-invasive assessment of diabetes-related changes in the dermal microvasculature and skin micro-anatomy,resolved with unprecedented sensitivity and detail without the need for contrast *** unique imaging contrast,we explored a possible role for RSOM as an investigational tool in diabetes healthcare and offer the first comprehensive study investigating the relationship between different diabetes complications and microvascular features in *** applied RSOM to scan the pretibial area of 95 participants with diabetes mellitus and 48 age-matched volunteers without diabetes,grouped according to disease complications,and extracted six label-free optoacoustic biomarkers of human skin,including dermal microvasculature density and epidermal parameters,based on a novel image-processing *** then correlated these biomarkers to disease severity and found statistically significant effects on microvasculature parameters as a function of diabetes *** discuss how label-free RSOM biomarkers can lead to a quantitative assessment of the systemic effects of diabetes and its complications,complementing the qualitative assessment allowed by current clinical metrics,possibly leading to a precise scoring system that captures the gradual evolution of the disease.

关键词： diabetes anatomy precise

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Optical imaging of post-embryonic zebrafish using multi orientation raster scan optoacoustic mesoscopy

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Light(Science & Applications) 2016年第1期5卷 336-341页

作者： murad omar Johannes Rebling Kai Wicker Tobias Schmitt-Manderbach Mathias Schwarz Jérôme Gateau Hérnan López-Schier Timo Mappes Vasilis Ntziachristos Chair for Biological Imaging Technische Universität MünchenMünchen D-81675Germany Institute for Biological and Medical Imaging Helmholtz Zentrum MünchenNeuherberg D-85764Germany Carl Zeiss AG Corporate Research and TechnologyJena D-07745Germany ESPCI Paris PSL Research UniversityCNRSINSERMInstitut LangevinParis F-75005France Research Unit Sensory Biology and Organogenesis Helmholtz Zentrum MünchenNeuherberg D-85764Germany Carl Zeiss Vision International GmbH Technology&InnovationAalen D-73430Germany

Whole-body optical imaging of post-embryonic stage model organisms is a challenging and long sought-after *** requires a combination of high-resolution performance and high-penetration ***(photoacoustic)mesoscopy holds great promise,as it penetrates deeper than optical and optoacoustic microscopy while providing high-spatial ***,optoacoustic mesoscopic techniques only offer partial visibility of oriented structures,such as blood vessels,due to a limited angular detection aperture or the use of ultrasound frequencies that yield insufficient *** introduce 3601 multi orientation(multi-projection)raster scan optoacoustic mesoscopy(MORSOM)based on detecting an ultra-wide frequency bandwidth(up to 160 MHz)and weighted deconvolution to synthetically enlarge the angular *** report unprecedented isotropic inplane resolution at the 9–17μm range and improved signal to noise ratio in phantoms and opaque 21-day-old *** find that MORSOM performance defines a new operational specification for optoacoustic mesoscopy of adult organisms,with possible applications in the developmental biology of adulthood and aging.

关键词： deconvolution development mesoscopy multiview optoacoustics photoacoustics

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Structural, electronic, and optical studies of chalcogenides stannite Cu2CdSnX4（X=S, Se, and Te）: insights from the DFT study

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Optoelectronics Letters 2025年第2期21卷 69-76页

作者： Jamal GUERROUM Mohamed AL-HATTAB Lhoucine MOUDOU Khalid RAHMANI Youssef LACHTIOUI omar BAJJOU Laboratory of Engineering in Chemistry and Physics of Matter Faculty of Sciences and Technics Sultan Moulay Slimane University Ecole Normale Supérieure Mohammed V University in Rabat College of Graduate Studies University of South Africa

In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu2CdSnX4（X=S,Se,Te） *** calculations are based on the density functional theory （DFT） method and are performed using the Cambridge sequential total energy package （CASTEP） code included in the Biovia Material Studio 20 *** optical properties have been studied in a domain that extends energetically from 10 meV to 40 *** results show that Cu2CdSnX4（X=S,Se,Te） stannite exhibits absorption in the visible region,the refractive index decreases with increasing energy,and the refractive index values are n=3.2,3.73 and 3.75 for Cu2CdSnS4,Cu2CdSnSe4and Cu2CdSnTe4,*** show also high conductivity,which implies that this material is promising for solar *** results argue in favor of the use of these materials in various potential *** density of state,band structures,and structural properties of Cu2CdSnX4（X=S,Se,and Te） stannite are also studied in this work.

关键词： Refractive index

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Thermospheric neutral wind studies over the equatorial region:A review

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Earth and Planetary Physics 2025年第1期9卷 81-100页

作者： Siti Syazwani Nasuha Idahwati Sarudin Nurul Shazana Abdul Hamid Ahmad Fairuz omar School of Physics Universiti Sains Malaysia11800 USMPulau PinangMalaysia Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Space Science Centre(ANGKASA) Institute of Climate ChangesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several ***,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still *** ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric ***,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain *** address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different *** low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip *** neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the ***,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be *** review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting.

关键词： thermospheric neutral wind thermosphere-ionosphere system dip equator equatorial region

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Application of solvent evaporation technique for pure drug crystal spheres preparation

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Particuology 2022年第8期20卷 79-89页

作者： omar Mady Department of Pharmaceutical Technology Faculty of Pharmacy Tanta UniversityEgypt

An innovative application ofthe solventevaporation technique was *** tech nique is a technique for drug encapsulation and nanosphere *** widely used technique is also facing the problem of low actual drug entrapment percent,which is not economic from the industrial *** goal of this work is trying to use the advantage of this technique concerning the product sphericity and the ability to control particle size,to prepare a drug as pure crystals *** is selected as a model *** spheres are formed by using Polyvinyl pyrrolidone(PVP)or Polyethylene glycol(PEG)as an anti-aggregating agent but not formed on using tween or *** size and actual drug content depend on the concentrations the anti-aggregating agent *** of the drug crystal spheres are porous with empty sphere internal structure on using PvP but spongy and rough on using *** drug has its identity chemical form in the drug crystal *** scan of spheres prepared on using PEG showed a characteristic ether *** showed melting endothermic peak of PEG,but X-ray showed minor change in the drug crystal *** release profiles from crystal spheres prepared with the same anti-aggregating agent are close to each *** drug release profiles from drug crystal spheres prepared by using PEG are more controlled than that prepared by using *** drug release mechanism is *** was concluded that,the same technique could be suggested for preparation ofother biomedical material in pure crystals spheres with controlled particle *** properties may encourage to prepare very small particles with spherical shape for inhalation or injection as an innovative particle technology application for the widely used technique.

关键词： Solvent evaporation technique Drug crystal spheres Ibuprofen Polyvinyl pyrrolidone Polyethylene glycol

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Monolayer MoS_(2)/n-Si Heterostructure Schottky Solar Cell

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Journal of Renewable Materials 2022年第7期10卷 1979-1988页

作者： omar Salih omar The University of Duhok College of ScienceDepartment of PhysicsDuhokKurdistan RegionIraq

Monolayer MoS_(2)has a promising optoelectronics property,with a bandgap in the visible range;the material is a potential candidate for solar cell *** this work,we grew MoS_(2)monolayers using a low-pressure chemical vapor deposition *** produce uniform wafer-scale MoS_(2)monolayer films,precursors molybdenum dioxide(MoO_(2))and sulfur(S)are *** force microscopy was used to quantify the thickness of the monolayers,and the result was validated by Raman *** electron microscopy(TEM)was used to confirm the crystalline quality of the monolayers,and photoluminescence spectroscopy was used to evaluate their optical *** were able to create a Schottky solar cell with a MoS_(2)monolayer up to 1 cm2 area by transferring monolayer film to n-type *** MoS_(2)/n-Si Schottky solar cell demonstrated photovoltaic characteristics with a short circuit current density of 14.8 mA cm^(-2)and an open-circuit voltage of 0.32 V under 100 mW cm^(-2)*** fill factor and energy conversion efficiency were 53%and 2.46%,respectively,with the highest external quantum efficiency at 530 nm being 44%.

关键词： MoS_(2)monolayers chemical vapor deposition Schottky solar cell

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VISCOMETRIC INVESTIGATIONS OF POLYVINYLPYRROLIDONE IN MIXED SOLVENTS AND WITH VARYING TEMPERATURE

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Chinese Journal of Polymer Science 2005年第4期23卷 367-371页

作者： omar Melad omar Abu-Tiem Rajai Baraka Chemistry Department

The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in *** intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent *** was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in *** viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_*** effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.

关键词： Polyvinylpyrrolidone Intermolecular excluded volume effect Intrinsic viscosity

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Reintegrating nanogranitoid inclusion composition to reconstruct the prograde history of melt-depleted rocks

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Geoscience Frontiers 2019年第2期10卷 517-525页

作者： omar Bartoli Department of Geosciences University of Padova

A recent fascinating development in the study of high-grade metamorphic basements is represented by the finding of tiny inclusions of crystallized melt(nanogranitoid inclusions) hosted in peritectic phases of migmatites and granulites. These inclusions have the potential to provide the primary composition of crustal melts at the source. A novel use of the recently-published nanogranitoid compositional database is presented here. Using granulites from the world-renowned Ivrea Zone(NW Italy) on which the original melt-reintegration approach has been previously applied, it is shown that reintegrating melt inclusion compositions from the published database into residual rock compositions can be a further useful method to reconstruct a plausible prograde history of melt-depleted rocks. This reconstruction is fundamental to investigate the tectonothermal history of geological terranes.

关键词： Nanogranitoids Melt-reintegration Granulite High-temperature metamorphism

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