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X-ray polarimetry and its application to strong-field quantum electrodynamics

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High Power Laser Science and engineering 2023年第6期11卷 47-70页

作者： Qiqi Yu Dirui Xu Baifei Shen thomas e.cowan Hans-Peter Schlenvoigt Shanghai Normal University ShanghaiChina Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Technische Universität Dresden DresdenGermany

Polarimetry is a highly sensitive method to quantify changes of the polarization state of light when passing through matter and is therefore widely applied in material *** progress of synchrotron and X-ray free electron laser(XFeL)sources has led to significant developments of X-ray polarizers,opening perspectives for new applications of polarimetry to study source and beamline parameters as well as sample characteristics.X-ray polarimetry has shown to date a polarization purity of less than 1.4×10^(-11),enabling the detection of very small signals from ultrafast phenomena.A prominent application is the detection of vacuum *** birefringence is predicted in quantum electrodynamics and is expected to be probed by combining an XFeL with a petawatt-class optical *** review how source and optical elements affect X-ray polarimeters in general and which qualities are required for the detection of vacuum birefringence.

关键词： birefringence polarimetry polarizer quantum electrodynamics X-rays

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Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.James J.e.cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

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Aulacaspis yasumatsui infestations accelerate Cycas leaf litter decomposition and nutrient release

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Pedosphere 2024年第3期34卷 681-684页

作者： thomas e.MARLeR Bagong Kaalaman Botanikal Institute 15 Rizal StreetBarangay MalabañasAngeles City 2009(Philippines)

Dear editor,Numerous aspects of ecosystem ecology are influenced by insects(Prasad,2022).Herbivory of plant organs by insects may influence the biogeochemistry of forests by changing the speed of litter decomposition(Schowalter,2022).Cycas micronesica *** is the only native gymnosperm in the Mariana *** once-abundant tree experienced no known lethal threats prior to the 2003 invasion of Guam by the scale Aulacaspis yasumatsui Takagi(Marler,2012).This insular case study has been the subject of abundant research(Marler et al.,2021).Changes to leaf litter chemistry improved litter quality following *** infestations(Marler and Dongol,2016),but the prediction of increased decomposition speed has not been confirmed with experimental incubations.

关键词： litter fir release

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enhanced ion acceleration from transparency-driven foils demonstrated at two ultraintense laser facilities

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Light(Science & Applications) 2023年第4期12卷 593-604页

作者： Nicholas P.Dover Tim Ziegler Stefan Assenbaum Constantin Bernert Stefan Bock Florian-emanuel Brack thomas e.cowan emma J.Ditter Marco Garten Lennart Gaus Ilja Goethel George S.Hicks Hiromitsu Kiriyama thomas Kluge James K.Koga Akira Kon Kotaro Kondo Stephan Kraft Florian Kroll Hazel F.Lowe Josefine Metzkes-Ng Tatsuhiko Miyatake Zulfikar Najmudin thomas Püschel Martin Rehwald Marvin Reimold Hironao Sakaki Hans-Peter Schlenvoigt Keiichiro Shiokawa Marvin e.P.Umlandt Ulrich Schramm Karl Zeil Mamiko Nishiuchi Kansai Photon Science Institute National Institutes for Quantum Science and Technology8-1-7 UmemidaiKizugawaKyoto 619-0215Japan The John Adams Institute for Accelerator Science Blackett LaboratoryImperial College LondonLondon SW72AZUnited Kingdom Helmholtz-Zentrum Dresden-Rossendorf 01328 DresdenGermany Technische Universitat Dresden 01069 DresdenGermany Interdiscipllinary Graduate School of engineering Sciences Kyushu University6-1Kasuga-KoenKasugaFukuoka 816-8580Japan

Laser-driven ion sources are a rapidly developing technology producing high energy,high peak current *** suitability for applications,such as compact medical accelerators,motivates development of robust acceleration schemes using widely available repetitive ultraintense femtosecond *** applications not only require high beam energy,but also place demanding requirements on the source stability and *** can be seriously affected by the laser temporal contrast,precluding the replication of ion acceleration performance on independent laser systems with otherwise similar ***,we present the experimental generation of>60 MeV protons and>30 MeV u-1 carbon ions from sub-micrometre thickness Formvar foils irradiated with laser intensities>1021 *** are accelerated by an extreme localised space charge field≥30TVm-1,over a million times higher than used in conventional *** field is formed by a rapid expulsion of electrons from the target bulk due to relativistically induced transparency,in which relativistic corrections to the refractive index enables laser transmission through normally opaque *** replicate the mechanism on two different laser facilities and show that the optimum target thickness decreases with improved laser contrast due to reduced *** demonstration that energetic ions can be accelerated by this mechanism at different contrast levels relaxes laser requirements and indicates interaction parameters for realising application-specific beam delivery.

关键词： acceleration intense transparency

Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： thomas J.Algeo Jun Shen State Key Laboratory of Biogeology and environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

effects of the urban landscape on heatwave-mortality associations in Hong Kong: comparison of different heatwave definitions

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Frontiers of environmental Science & engineering 2024年第1期18卷 145-156页

作者： Jinglu Song Yi Lu thomas Fischer Kejia Hu Department of Urban Planning and Design Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China Department of Architecture and Civil engineering City University of Hong KongKowloon TongHong Kong 999077China environmental Assessment and Management Research Centre School of Environmental SciencesUniversity of LiverpoolLiverpool L35TRUK Research Unit for environmental Sciences and Management Faculty of Natural and Agricultural SciencesNorth West UniversityPotchefstroom 31750South Africa Institute of Big Data in Health Science School of Public HealthZhejiang UniversityZijingang CampusHangzhou 310058China

Despite increased attention given to potential modifiers of temperature-mortality associations, evidence for variations between different urban landscape characteristics remains limited. It is in this context that in this paper effect modifications of multiple urban landscape characteristics are explored under different heatwave definitions for different age groups and gender in Hong Kong, China. Daily meteorological data and heatwave-related mortality counts from 2008 to 2017 were collected from the Hong Kong Census and Statistics Department, China. A case-only design was adopted, combined with logistic regression models to examine the modification effects of five urban landscape characteristics under six heatwave definitions. Stratified analyses were conducted to investigate age- and gender-specific effect modifications. It is found that individuals living in greener areas experienced lower levels of mortality during or immediately after heatwaves. In contrast, a higher building density and nighttime land surface temperature (LST) were associated with a higher heatwave-related mortality risk. Pronounced effect modifications of these urban landscape characteristics were observed under hotter and longer heatwaves, and in older adults (age ≥ 65 years) and males. The findings provide a scientific basis for policymakers and practitioners when considering measures for coping with hotter, longer, and more frequent heatwaves in the context of global climate change.

关键词： Urban landscape Heatwave Mortality effect modification Intra-urban differences Health risk reduction

Development of gradient boosting-assisted machine learning data-driven model for free chlorine residual prediction

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Frontiers of environmental Science & engineering 2024年第2期18卷 35-46页

作者： Wiley Helm Shifa Zhong elliot Reid thomas Igou Yongsheng Chen School of Civil and environmental engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of ecological and environmental Sciences East China Normal UniversityShanghai 200241China

Chlorine-based disinfection is ubiquitous in conventional drinking water treatment (DWT) and serves to mitigate threats of acute microbial disease caused by pathogens that may be present in source water. An important index of disinfection efficiency is the free chlorine residual (FCR), a regulated disinfection parameter in the US that indirectly measures disinfectant power for prevention of microbial recontamination during DWT and distribution. This work demonstrates how machine learning (ML) can be implemented to improve FCR forecasting when supplied with water quality data from a real, full-scale chlorine disinfection system in Georgia, USA. More precisely, a gradient-boosting ML method (CatBoost) was developed from a full year of DWT plant-generated chlorine disinfection data, including water quality parameters (e.g., temperature, turbidity, pH) and operational process data (e.g., flowrates), to predict FCR. Four gradient-boosting models were implemented, with the highest performance achieving a coefficient of determination, R2, of 0.937. Values that provide explanations using Shapley’s additive method were used to interpret the model’s results, uncovering that standard DWT operating parameters, although non-intuitive and theoretically non-causal, vastly improved prediction performance. These results provide a base case for data-driven DWT disinfection supervision and suggest process monitoring methods to provide better information to plant operators for implementation of safe chlorine dosing to maintain optimum FCR.

关键词： Machine learning Data-driven modeling Drinking water treatment Disinfection Chlorination

eZH2 inhibitors promote β-like cell regeneration in young and adult type 1 diabetes donors

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Signal Transduction and Targeted Therapy 2024年第2期9卷 679-692页

作者： Keith Al-Hasani Safiya Naina Marikar Harikrishnan Kaipananickal Scott Maxwell Jun Okabe Ishant Khurana thomas Karagiannis Julia J.Liang Lina Mariana thomas Loudovaris thomas Kay Assam el-Osta epigenetics in Human Health and Disease Program Baker Heart and Diabetes Institute75 Commercial RoadMelbourne 3004 VICAustralia Department of Diabetes Central Clinical SchoolMonash UniversityMelbourne 3004 VICAustralia epigenetics in Human Health and Disease Laboratory Central Clinical SchoolMonash UniversityMelbourne 3004 VICAustralia School of Science STEM CollegeRMIT UniversityMelbourne 3001 VICAustralia Immunology and Diabetes Unit St Vincent’s Institute of Medical ResearchFitzroy 3065 VICAustralia Department of Medicine and Therapeutics The Chinese University of Hong KongSha TinHong Kong SAR Hong Kong Institute of Diabetes and Obesity Prince of Wales HospitalThe Chinese University of Hong Kong3/F Lui Che Woo Clinical Sciences Building30-32-Ngan Shing StreetSha TinHong Kong SAR Li Ka Shing Institute of Health Sciences The Chinese University of Hong KongSha TinHong Kong SAR Biomedical Laboratory Science Department of TechnologyFaculty of HealthUniversity College CopenhagenCopenhagenDenmark

β-cells are a type of endocrine cell found in pancreatic islets that synthesize,store and release *** type 1 diabetes(T1D),T-cells of the immune system selectively destroy the insulin-producingβ-*** of these cells leads to a lifelong dependence on exogenous insulin administration for ***,there is an urgent need to identify novel therapies that stimulateβ-cell growth and induceβ-cell *** and others have shown that pancreatic ductal progenitor cells are a promising source for regeneratingβ-cells for T1D owing to their inherent differentiation *** transcriptional suppression is refractory to exocrine reaction and tightly controls the regenerative potential by the eZH2 *** the present study,we show that transient stimulation of exocrine cells,derived from juvenile and adult T1D donors to the FDAapproved eZH2 inhibitors GSK126 and Tazemetostat(Taz)influence a phenotypic shift towards aβ-like cell *** transition from repressed to permissive chromatin states are dependent on bivalent H3K27me3 and H3K4me3 chromatin *** eZH2 is fundamental toβ-cell regenerative *** pancreatic ductal cells exhibit insulin production and secretion in response to a physiological glucose challenge ex *** pre-clinical studies underscore the potential of small molecule inhibitors as novel modulators of ductal progenitor differentiation and a promising new approach for the restoration ofβ-like cell function.

关键词： eZH2 struction inhibitors