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Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther n.Bukharskii n.Borisenko J.Jacoby X.F.Shen A.Pukhov n.E.Andreev O.n.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany national Research nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

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Hyper spectral resolution stimulated Raman spectroscopy with amplified fs pulse bursts

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Light(Science & Applications) 2024年第3期13卷 566-576页

作者： Hongtao Hu Tobias Flöry Vinzenz Stummer Audrius Pugzlys markus Zeiler Xinhua Xie Aleksei Zheltikov Andrius Baltuška Photonics Institute Technische Universität WienGußhausstraße 27-29Vienna A-1040Austria SwissFEL Paul Scherrer InstituteVilligen PSI 5232Switzerland Institute for Quantum Science and Engineering Department of Physics and AstronomyTexas A&M UniversityCollege StationTX 77843USA

We present a novel approach for Stimulated Raman Scattering(SRS)spectroscopy in which a hyper spectral resolution and high-speed spectral acquisition are achieved by employing amplified offset-phase controlled fs-pulse *** investigate the method by solving the coupled non-linear Schrödinger equations and validate it by numerically characterizing SRS in molecular nitrogen as a model *** spectral resolution of the method is found to be determined by the inverse product of the number of pulses in the burst and the intraburst pulse *** SRS spectrum is obtained through a motion-free scanning of the offset phase that results in a sweep of the Raman-shift *** to high spectral resolution and fast motion-free scanning the technique is beneficial for a number SRS-based applications such as gas sensing and chemical analysis.

关键词： compound spectral resolution

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Ovarian Tumors in Senegalese Women: impact of D-Loop mutations between Healthy and Cancerous Tissues

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Open Journal of Genetics 2024年第2期14卷 37-46页

作者： Rouguiyatou ka Fatimata mbaye Bineta Kénéme mbacké Sembène Genomics Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal

In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to Single nucleotide Polymorphisms (SnPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million SnPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the D-loop region of mtDnA on ovarian cancer in Senegalese women. This study involved searching for mutations in our study population after DnA extraction and sequencing. mutations were found after a comparison of our sequences with the Cambridge reference sequence (nC_012920). The mutations found in the DnA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.

关键词： Ovarian Cancer mutations D-Loop Heteroplasmy

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Two distinct subpopulations of marginal zone B cells exhibit differential antibody-producing capacities and radioresistance

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Cellular & molecular immunology 2024年第4期21卷 393-408页

作者： Sujin Lee Yeunjung Ko Hyun Woo Lee Won Joon Oh Hun Gi Hong Dinuka Ariyaratne Se Jin im Tae Jin Kim Department of immunology Graduate School of Basic Medical ScienceSungkyunkwan University School of MedicineSuwon16419Republic of Korea Department of immunology and molecular medicine Faculty of Medical SciencesUniversity of Sri JayewardenepuraNugegodaSri Lanka Present address:immunology and microbiology Graduate Program Baylor College of MedicineHoustonTX77030USA

marginal zone(mZ)B cells,which are splenic innate-like B cells that rapidly secrete antibodies(Abs)against blood-borne pathogens,are composed of heterogeneous ***,we showed that mZ B cells can be divided into two distinct subpopulations according to their CD80 expression ***80^(high)mZ B cells exhibited greater Ab-producing,proliferative,and IL-10-secreting capacities than did CD80^(low)mZ B ***,CD80^(high)mZ B cells survived 2-Gy whole-body irradiation,whereas CD80^(low)mZ B cells were depleted by irradiation and then repleted with one month after *** of CD80^(low)mZ B cells led to accelerated development of type II collagen(CII)-induced arthritis upon immunization with bovine ***80^(high)mZ B cells exhibited higher expression of genes involved in proliferation,plasma cell differentiation,and the antioxidant ***80^(high)mZ B cells expressed more autoreactive B cell receptors(BCRs)that recognized double-stranded DnA or CII,expressed more immunoglobulin heavy chain sequences with shorter complementarity-determining region 3 sequences,and included more clonotypes with no n-nucleotides or with B-1a BCR sequences than CD80^(low)mZ B *** transfer experiments showed that CD21^(+)CD23^(+)transitional 2 mZ precursors preferentially generated CD80^(low)mZ B cells and that a proportion of CD80^(low)mZ B cells were converted into CD80^(high)mZ B cells;in contrast,CD80^(high)mZ B cells stably remained CD80^(high)mZ B *** summary,mZ B cells can be divided into two subpopulations according to their CD80 expression levels,Ab-producing capacity,radioresistance,and autoreactivity,and these findings may suggest a hierarchical composition of mZ B cells with differential stability and BCR specificity.

关键词： marginal Zone B Cell CD80 Autoreactivity Radioresistance

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nomogram to predict severe retinopathy of prematurity in Southeast China

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 282-288页

作者： Dan Liu Xing-Yong Li Hong-Wu He ka-Lu Jin Ling-Xia Zhang Yang Zhou Zhi-min Zhu Chen-Chen Jiang Hai-Jian Wu Sui-Lian Zheng Department of Ophthalmology the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Eye Hospital and School of Ophthalmology and Optometry Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Taizhou Optometry Hospital Taizhou 318001Zhejiang ProvinceChina Department of Ophthalmology Jiaxing Maternity and Child Health Care HospitalJiaxing 314009Zhejiang ProvinceChina Department of Ophthalmology Taizhou Women and Children’s Hospital of Wenzhou Medical UniversityTaizhou 318001Zhejiang ProvinceChina Clinical medical Research Center the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Ophthalmology Taizhou Municipal HospitalTaizhou 318099Zhejiang ProvinceChina

Aim:To define the predictive factors of severe retinopathy of prematurity(ROP)and develop a nomogram for predicting severe ROP in southeast ***:Totally 554 infants diagnosed with ROP hospitalized in the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou medical University and hospitalized in Taizhou Women and Children’s Hospital were *** data and 43 candidate predictive factors of ROP infants were collected *** regression model was used to identify predictive factors of severe ROP and to propose a nomogram for individual risk prediction,which was compared with WInROP model and Digirop-Birth ***:Infants from the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou medical University(n=478)were randomly allocated into training(n=402)and internal validation group(n=76).Infants from Taizhou Women and Children’s Hospital were set as external validation group(n=76).Severe ROP were found in 52 of 402 infants,12 of 76 infants,and 7 of 76 infants in training group,internal validation group,and external validation group,*** weight[odds ratio(OR),0.997;95%confidence interval(CI),0.996-0.999;Pmultiple births(OR,1.885;95%CI,1.013-3.506;P=0.045),and non-invasive ventilation(OR,0.288;95%CI,0.146-0.570;Pntified as predictive factors for the prediction of severe ROP,by univariate analysis and multivariate *** predicting severe ROP based on the internal validation group,the areas under receiver operating characteristic curve(AUC)was 78.1(95%CI,64.2-92.0)for the nomogram,32.9(95%CI,15.3-50.5)for WInROP model,70.2(95%CI,55.8-84.6)for Digirop-Birth *** external validation group,AUC of the nomogram was also higher than that of WInROP model and Digirop-Birth model(80.2 versus 51.1 and 63.4).The decision curve analysis of the nomogram demonstrated better clinical efficacy than that of WInROP model and Digirop-Birth *** calibration curves demonst

关键词： retinopathy of prematurity nomogram predictive factor birth weight multiple births non-invasive ventilation

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Evolution of mother-to-Child HIV-1 Transmission Rate in mali from 2009 to 2018

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Advances in microbiology 2024年第5期14卷 256-267页

作者： Alou Sanogo mohamed Ag Baraïka maïga Aminata Demba Koita mahamadou Abdou mamadou Guindo Clémentine n’Diaye Fatoumata namoudou Traoré Abdoulaye Bagayoko Youssouf Diallo Flabou Bougoudogo Ibrehima Guindo national Institute for Public Health Bamako Mali Faculty of Pharmacy (FAPH) University of Science of Technical and Technology de Bamako Bamako Mali University Hospital Center (CHU)-Point G Bamako Mali Faculty of medecine and Odonto-Stomatology University of Science of Technical and Technology de Bamako Bamako Mali Sector Unit for the Fight against AIDS Tuberculosis and Hepatitis Bamako Mali UnICEF (United nations Children’ s Fund) Bamako Mali

Despite enormous efforts to achieve the goal of eliminating mother-to-child transmission of HIV-1, it remains a major challenge for many countries in sub-Saharan Africa, particularly mali. Our objective is to assess changes in the rate of mother-to-child transmission of HIV-1. We conducted a cross-sectional study between January 1, 2009 to December 31, 2018 (10 years) of early diagnosis activity in newborns and children born to HIV-1-positive mothers at the national Institute for Public Health (InSP). The samples came from health and referral centers in mali. All samples were received at the Laboratory of molecular Biology at the InSP. Proviral DnA extraction was performed from a blood spot sample with a Roche DnA kit, Cobas AmpliPrep/Cobas Taqman HIV-1 qualitative Test, V2.0 (Roche molecular System, Inc, USA) following the company procedures. molecular diagnosis was performed using the same kits using an algorithm of three identical PCRs. The Epi Info version 7 software was used for data analysis with a significance threshold of 5%. A total of 10,714 samples of infants and children born to HIV-positive mothers were analyzed by PCR. ninety-six percent of mothers were on ARV prophylaxis (AZT 3TC nVP and AZT nVP) and 60% of newborns received the same ARV prophylaxis. Of these children, 956 tested positive with an overall transmission rate of 8.92%, varying between 7.27% in 2009 and 08.01% in 2018. This rate was relatively low among children receiving prophylaxis at 2.04% and remained high for children who received breastfeeding at 5.62%. However, the transmission rate remains low for those who have benefited from mixed and artificial breastfeeding at 1.58% and 1.27% respectively. A significant proportion of children remained infected by their mothers during pregnancy, childbirth or breastfeeding. This study shows the importance of early diagnosis of HIV in children using molecular technology.

关键词： Early Diagnosis mothers-to-Child newborns PCR DnA HIV-1

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multi-exponential model to describe pressure-dependent P-and S-wave velocities and its use to estimate the crack aspect ratio

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Journal of Rock mechanics and Geotechnical Engineering 2022年第2期14卷 385-395页

作者： mihály Dobróka norbert Péter Szabó Tünde Edit Dobróka mátyás Krisztián Baracza Department of Geophysics University of MiskolcMiskolc-Egyetemváros3515Hungary mTA-mE Geoengineering Research Group University of MiskolcMiskolc-Egyetemváros3515Hungary Research Institute of Applied Earth Sciences University of MiskolcMiskolc-Egyetemváros3515Hungary

We present new quantitative model describing the pressure dependence of acoustic P-and S-wave *** that a variety of individual mechanisms or defects(such as cracks,pore collapse and grain crushing)can contribute to the pressure-dependent change of the wave velocity,we order a characteristic pressure to all of them and allow a series of exponential terms in the description of the(Pand S-waves)velocity-pressure *** estimate the parameters of the multi-exponential rock physical model in inversion procedures using laboratory measured P-and S-wave velocity *** is known,the conventional damped least squares method gives acceptable results only when one or two individual mechanisms are *** the number of exponential terms leads to highly nonlinear ill-posed inverse *** to this reason,we develop the spectral inversion method(Sim)in which the velocity amplitudes(the spectral lines in the characteristic pressure spectrum)are only considered as *** characteristic pressures(belonging to the velocity amplitudes)are excluded from the set of inversion unknowns,instead,they are defined in a set of fixed positions equidistantly distributed in the actual interval of the independent variable(pressure).Through this novel linear inversion method,we estimate the parameters of the multi-exponential rock physical model using laboratory measured P-and S-wave velocity *** characteristic pressures are related to the closing pressures of cracks which are described by well-known rock mechanical relationships depending on the aspect ratio of elliptical *** gives the possibility to estimate the aspect ratios in terms of the characteristic pressures.

关键词： multi-exponential rock physical model Spectral inversion method(Sim) Crack aspect ratio Characteristic pressures

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Spatial analysis of vegetation cover response to climate trends in Khakassia(South Siberia)

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Journal of mountain Science 2023年第10期20卷 2869-2884页

作者： im Sergei Institute of natural Sciences and mathematics Khakassian State University named after N.F.KatanovAbakan 655000Russia V.n.Sukachev Institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660041Russia Institute of Space Research and High Technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk660014Russia

An analysis of the changes in vegetation cover on the territory of the Republic of Khakassia in 2000–2021 due to climatic trends was carried out based on the mODIS *** changes in vegetation cover were estimated based on trends in normalized Difference Vegetation Index(nDVI)and Enhanced Vegetation Index(EVI).In general,in the 21st century,an increase in the biomass of vegetation cover is *** trends were observed in 16%–22%of the territory,and negative only in 1%–3%.For about 20%of the analyzed territory,a significant influence of climate on the changes in vegetation cover was *** most pronounced negative impact on vegetation cover was caused by summer air and soil temperatures,spring temperature,and summer winds,and the positive impact was caused by summer precipitation and soil *** response of the vegetation cover to climate was non-uniform concerning the ***,a significant correlation with the amount of precipitation was observed for~20%–35%of vegetation growing below 600 m above sea level and for less than 5%above this *** negative effect of summer temperatures on plants prevailed mainly at an elevation below~1400 m above sea *** climate change is likely to lead to significant degradation of vegetation in the steppe and foreststeppe in Khakassia in the coming decades.

关键词： Khakassia South Siberia Vegetation cover Climate trends Remote sensing mODIS nDVI EVI Relief

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Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 433-442页

作者： katarína Gáborová marcela Achimovičová michal Hegedüs Vladimír Girman mária kaňuchová Erika Dutková Institute of Geotechnics Slovak Academy of SciencesKošice04001Slovakia Institute of metallurgy Faculty of MaterialsMetallurgy and RecyclingTechnical UniversityKošice04201Slovakia Synthon s.r.o.Blansko67801Czech Republic Faculty of Science Pavol JozefŠafárik UniversityKošice04154Slovakia Institute of Earth Resources Faculty of MiningEcologyProcess Control and GeotechnologiesTechnical UniversityKošice04200Slovakia

Copper(I)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball *** kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se *** X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)Se with the crystallite size∼25 *** surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu^(+)and Se^(2−)oxidation *** electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as *** optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence *** direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size *** type of Cu_(2)Se synthesis can be easily adapted to production dimensions using an industrial vibratory *** advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu_(2)Se.

关键词： Cu_(2)Se berzelianite nanocrystalline semiconductor mechanochemical synthesis planetary ball mill

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Deciphering the controlling factors for phase transitions in zeolitic imidazolate frameworks

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national Science Review 2024年第4期11卷 151-163页

作者： Tao Du Shanwu Li Sudheer Ganisetti mathieu Bauchy Yuanzheng Yue morten m.Smedskjaer Department of Chemistry and Bioscience Aalborg University Department of mechanical Engineering-Engineering mechanics Michigan Technological University Physics of Amo Rphous and Inorganic Solids Laboratory(PARISlab) Department of Civil and Environmental EngineeringUniversity of CaliforniaLos Angeles

Zeolitic imidazolate frameworks（ZIFs） feature complex phase transitions, including polymorphism,melting, vitrification, and polyamorphism. Experimentally probing their structural evolution during transitions involving amorphous phases is a significant challenge, especially at the medium-range length scale. To overcome this challenge, here we first train a deep learning-based force field to identify the structural characteristics of both crystalline and non-crystalline ZIF phases. This allows us to reproduce the structural evolution trend during the melting of crystals and formation of ZIF glasses at various length scales with an accuracy comparable to that of ab initio molecular dynamics, yet at a much lower computational cost. Based on this approach, we propose a new structural descriptor, namely, the ring orientation index, to capture the propensity for crystallization of ZIF-4(Zn（im）2, im = C3H3n2-) glasses, as well as for the formation of ZIF-zni(Zn（im）2) out of the high-density amorphous phase. This crystal formation process is a result of the reorientation of imidazole rings by sacrificing the order of the structure around the zinc-centered tetrahedra. The outcomes of this work are useful for studying phase transitions in other metal-organic frameworks（mOFs） and may thus guide the development of mOF glasses.

关键词： metal-organic frameworks phase transitions melting glass formation transferable deep learning force field ring orientation

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