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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

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The Effect of Retinoic Acid on Neutrophil Innate Immune Interactions With Cutaneous Bacterial pathogens

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Infectious Microbes & diseases 2024年第2期6卷 65-73页

作者： Alexandra Stream ross Corriden Simon döhrmann Richard L.Gallo Victor Nizet Ericka L.Anderson division of Host-Microbe Systems and Therapeutics Department of PediatricsUniversity of California San Diego School of MedicineLa JollaCaliforniaUSA department of dermatology University of California San Diego School of MedicineLa JollaCaliforniaUSA Skaggs School of pharmacy and pharmaceutical Sciences University of California San DiegoLa JollaCaliforniaUSA

Vitamin A and its biologically active derivative,retinoic acid(RA),are important for many immune ***,in particular,is essential for the development of immune cells,including neutrophils,which serve as a front-line defense against *** vitamin A deficiency has been linked to higher susceptibility to infections,the precise role of vitamin A/RA in host-pathogen interactions remains poorly ***,we provided evidence that RA boosts neutrophil killing of methicillin-resistant Staphylococcus aureus(MRSA).RA treatment stimulated primary human neutrophils to produce reactive oxygen species,neutrophil extracellular traps and the antimicrobial peptide cathelicidin(LL-37).Because RA treatment was insufficient to reduce MRSA burden in an in vivo murine model of skin infection,we expanded our analysis to other infectious *** did not affect the growth of a number of common bacterial pathogens,including MRSA,Escherichia coli K1 and pseudomonas aeruginosa;however,RA directly inhibited the growth of group A Streptococcus(GAS).This antimicrobial effect,likely in combination with RA-mediated neutrophil boosting,resulted in substantial GAS killing in neutrophil killing assays conducted in the presence of ***,in a murine model of GAS skin infection,topical RA treatment showed therapeutic potential by reducing both skin lesion size and bacterial *** findings suggest that RA may hold promise as a therapeutic agent against GAS and perhaps other clinically significant human pathogens.

关键词： retinoic acid neutrophil bacterial infection Staphylococcus aureus group A Streptococcus neutrophil extracellular traps antimicrobial peptide cathelicidin

Enantioselective iridium-catalyzed allylic substitution with a Reformatsky reagent: direct construction of β-stereogenic homoallylic esters

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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： debasis pal Kirana d.Veeranna Yuk Fai Wong p.Andrew Evans department of Chemistry Queen's University Xiangya School of pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

paper Analytical device for the Colourimetric detection of Alkaline phosphatase in Serum and Saliva

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Journal of Analysis and Testing 2024年第3期8卷 385-394页

作者： d.Alageswari A.Lakshmidevi p.E.Resmi p.V.Suneesh Aarathipradeep T.G.SatheeshBabu department of Chemistry Amrita School of Physical Sciences Coimbatore Amrita Vishwa Vidyapeetham Amrita Biosensor Research Lab Amrita School of Engineering Coimbatore Amrita Vishwa Vidyapeetham Amrita Biomedical Engineering Centre Amrita School of Engineering Coimbatore Amrita Vishwa Vidyapeetham

A paper analytical device (pAd) was developed for the colourimetric estimation of alkaline phosphatase (ALp). ALp catalyzes the hydrolysis of disodium phenyl phosphate (dSpp) to phenol, which then undergoes oxidative coupling with4-aminoantipyrine (4-AAp) producing a reddish brown-coloured quinone imine. The colourimetric reaction tested in solution has been translated onto a pAd for the point of care (poC) testing of ALp. A uniform colour was obtained in 25 min with the introduction of ALp onto the reagent drop cast paper device. The images obtained by scanning the pAd were processed using ImageJ software. The colour intensity obtained by image processing was proportional to the concentration of ALp present in the sample. ALp in serum and saliva samples were tested using the pAd in the range of 0 to 528 U/L and0 to 187 U/L, respectively. The interference studies revealed that the pAd was selective to ALp in the presence of other biomolecules. The pAd exhibited a limit of detection (LOd) of 3.3 U/L and a sensitivity of 48.36 a.u/Log(U/L) for serum ALp and LOd of 1.69 U/L and a sensitivity of 28.5 a.u/Log (U/L) for salivary ALp. The pAd showed good agreement with the clinical methods for real samples.

关键词： Alkaline phosphatase Colourimetry ImageJ paper analytical device point of care testing

Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3d time‑domain modelling

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Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.F.Esen O.Laghrouche p.K.Woodward d.Medina‑pineda Q.Corbisez J.Y.Shih d.p.Connolly Institute for High‑Speed Rail and System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway Research and Education University of BirminghamBirmingham B152TTUK

Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in *** is then compared to the performance of a ballasted ***,slab and ballasted track models are developed to replicate the full-scale testing of track *** the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track *** slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the *** travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical *** train loading methods are discussed,and the most practical approach is retained and ***,correlations are made between the geotechnical parameters of modern high-speed rail and conventional *** is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds.

关键词： High-speed railways Slab track New ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models

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Advances in teleophthalmology and artificial intelligence for diabetic retinopathy screening:a narrative review

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Annals of Eye Science 2024年第2期9卷 24-37页

作者： Tanvi Chokshi Maria Jessica Cruz Jonathon ross Glenn Yiu Tschannen Eye Institute Department of OphthalmologyUniversity of CaliforniaDavis HealthSacramentoCAUSA department of Research College of MedicineCalifornia Northstate UniversityElk GroveCAUSA

Background and Objective:Advances in teleophthalmology and artificial intelligence(AI)for diabetic retinal screening is of growing public health ***,only 30–40%of patients with diabetes adhere to recommended diabetes screening *** enhance early detection and reduce vision threatening complications,there has been a growing number of teleophthalmology programs and novel AI algorithms with the aim to improve eye care *** purpose of this review is to assess current literature on teleophthalmology and AI for use in diabetic retinopathy(dR)screening,and to discuss advances and barriers to these innovative ***:Literature review involving teleophthalmology and AI for dR screening,with focus on the past *** Content and Findings:Teleophthalmology has demonstrated the ability to increase dR screening rates,enable earlier eye care access,and reduce healthcare *** AI-based dR screening programs appear accurate and effective,but detection of other ocular pathologies is still under development and not yet approved in the United ***,technological,financial,and legal barriers limit widespread adoption and long-term sustainability of teleophthalmology ***:The use of teleophthalmology and AI algorithms expands eye care access and helps prevent vision loss from dR and potentially other sight threatening *** in the process utilized for arriving at a particular diagnosis or decision to refer,often referred to as the“black box”,remains a multifaceted issue within the field of telemedicine for developing trust and improving patient-centered outcomes.

关键词： Teleophthalmology artificial intelligence(AI) diabetic retinopathy(dR) screening public health

Limosilactobacillus mucosae FZJTZ26M3 prevents NAFLd in mice through modulation of lipid metabolism and gut microbiota dysbiosis

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Food Science and Human Wellness 2024年第3期13卷 1589-1601页

作者： danting dang Bowen Li Mengfan ding Rpaul ross Catherine Stanton Jianxin Zhao Bo Yang Wei Chen State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi 214122China School of Food Science and Technology Jiangnan UniversityWuxi 214122China International Joint Research Center for probiotics&Gut Health Jiangnan UniversityWuxi 214122China ApC Microbiome Ireland University College CorkCork T12 YT20Ireland Teagasc Food Research Centre MooreparkFermoyCork T12 YT20Ireland National Engineering Research Center for Functional Food Jiangnan UniversityWuxi 214122China

Lactobacillus are considered promising therapeutic methods for nonalcoholic fatty liver disease(NAFLd).The effects of two strains of Ltmosilactobacillus mucosae on NAFLd were investigated in this ***-old male C57BL/6J mice were divided into 4 groups(n=8 per group,Control,Model,FZJTZ26M3,FGSYC17L3).*** FZJTZ26M3 reduced the mice 's body weight,liver weight,and adipose tissue weight after 12 weeks of *** to serum analysis,total cholesterol,triacylglycerol,and low-density lipoprotein cholesterol significantly decreased after *** FZJTZ26M3 *** pathology showed that *** FZJTZ26M3 was effective to ameliorate lipid deposition in NAFLd ***,the expression of the gene related to lipid metabolism in the liver and adipose tissue was analyzed,and the results indicated that *** FZJTZ26M3 could alleviate NAFLd by regulating lipid ***,the results of 16S rRNA gene sequencing revealed a drop in the relative abundance of Ruminococcaceae,which is linked to inflammation,but the relative abundance of a potential probiotic Akkermansia significantly increased after *** FZJTZ26M3 ***,*** FZJTZ26M3 could be a candidate to prevent NAFLd.

关键词： Limosilactobacillus mucosae Nonalcoholic fatty liver disease(NAFLd) probiotic Lipid metabolism Gut microbiota

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Low bend loss,high index,composite morphology ultra-fast laser written waveguides for photonic integrated circuits

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Light(Advanced Manufacturing) 2024年第1期5卷 50-59页

作者： Andrew ross-Adams Toney Teddy Fernandez Michael Withford Simon Gross MQ photonics School of Mathematics and Physical SciencesMacquarie University2109Australia School of Engineering Macquarie University2109Australia

We demonstrate a novel,composite laser written 3d waveguide,fabricated in boro-aluminosilicate glass,with a refractive index contrast of 1.12×10−*** waveguide is fabricated using a multi-pass approach which leverages the respective refractive index modification mechanisms of both the thermal and athermal inscription *** present the study and optimisation of inscription parameters for maximising positive refractive index change and ultimately demonstrate a dramatic advancement on the state of the art of bend losses in laser-written *** 1.0 dB cm−1 bend loss cut-off radius is reduced from 10 mm to 4 mm,at a propagation wavelength of 1550 nm.

关键词： Ultrafast laser inscription Thermal inscription Cumulative heating Athermal inscription Multi-scan Multi-pass Half-scan Bend loss High index contrast photonic integrated circuit

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert p.Hesselbach M.Schorner V.Bagnoud R.Belikov p.drechsel B.Heuser O.SHumphries p.Katrik B.Lindqvist C.Qu R.Redmer d.Riley G.Schaumann S.Schumacher A.Tauschwitz d.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major p.Neumayer d.Kraus Institut fur physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum dresden-rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for plasma physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure