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Organic Chemistry Frontiers 2022年第2期9卷 420-427页

作者： marta Gil-Ordonez Alicia Maestro Pablo Ortega Pablo G.Jambrina Jose M.Andres GIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica Facultad de CienciasUniversidad de ValladolidPaseo Belén 747011 ValladolidSpain Departamento de Química Física University of Salamanca37008 SalamancaSpain

Chiral pyrazolones with a spirocyclic centre at the C4-position are widely found in a large family of medically relevant *** recent years,organocatalysis,particularly that performed with quiral N-heterocyclic carbenes(NHCs),has allowed the enantioselective synthesis of these spirocyclic compounds despite its inherent *** this work,we describe the fully diastereo-and highly enantioselective synthesis of novel spirocyclic pyrazolone γ-butyrolactones via NHC-catalysed[3+2]annulation reaction of enals and 1H-pyrazol-4,*** understand the catalytic mechanism and origin of stereoselectivity,electronic structure calculations were carried *** considering various pathways,we concluded that the stereoselectivity-determining step is the formation of the lactone that proceeds after addition of the NHC derived homoenolate to the electrophilic carbonyl group of pyrazolin-4,*** calculations predict that the free energy barrier is lower for the(RS)product,which is also the main product experimentally obtained.

关键词： synthesis spiro mechanism

利用强子探针研究奇特原子核的点质子分布半径及强子探针效应

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Science Bulletin 2024年第11期69卷 1647-1652页

作者：张寂潮孙保华 Isao Tanihata Rituparna Kanungo Christoph Scheidenberger Satoru Terashima 王枫 Frederic Ameil Joel Atkinson Yassid Ayyad Soumya Bagchi Dolores Cortina-Gil Iris Dillmann Alfredo Estradé Alexey Evdokimov Fabio Farinon Hans Geissel Giulia Guastalla Rudolf Janik Satbir Kaur Ronja Knöbel Jan Kurcewicz Yury Litvinov Michele marta Magdalena Mostazo Ivan Mukha Chiara Nociforo Hooi Jin Ong Stephane Pietri Andrej Prochazka Branislav Sitar Peter Strmen Maya Takechi Junki Tanaka Jossitt Vargas Helmut Weick John Stuart Winfield School of Physics Beihang UniversityBeijing 100191China Research Center for Nuclear Physics(RCNP) Osaka UniversityOsaka 567-0047Japan Astronomy and Physics Department Saint Mary’s UniversityHalifax B3H 3C3Canada TRIUMF Vancouver V6T 4A3Canada GSI Helmholtzzentrum für Schwerionenforschung Darmstadt D-64291Germany Justus-Liebig University Gießn 35392Germany Helmholtz Research Academy Hesse for FAIR(HFHF) GSI Helmholtz Center for Heavy Ion ResearchGießn 35392Germany Universidad de Santiago de Compostela Santiago de Compostella E-15706Spain Department of Physics Indian Institute of Technology(Indian School of Mines)Dhanbad 826004India Faculty of Mathematics and Physics Comenius UniversityBratislava 84215Slovakia Department of Physics and Atmospheric Science Dalhousie UniversityHalifax B3H 4R2Canada

We report the charge-changing cross sections(σ_(cc))of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV,of which^(8,9)Li,^(10–12)Be,^(10,14,15)B,^(14,15,17–22)N and^(16)O on hydrogen and^(8,9)Li on carbon are for the first *** from the data set,we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both *** allows us to deduce proton radii(R_p)for the first time from the cross sections on *** identical R_p values are deduced from both target data for the neutron-rich carbon isotopes;however,the R_p from the hydrogen target is systematically smaller in the neutron-rich nitrogen *** calls for further experimental and theoretical investigations.

关键词： Exotic nuclei Nuclear size Reaction cross section Glauber model Radioactive ion beam

Incidence and prevalence of gastric neuroendocrine tumors in patients with chronic atrophic autoimmune gastritis

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World Journal of Gastrointestinal Oncology 2023年第8期15卷 1451-1460页

作者： Sara Massironi Camilla Gallo Alessandra Elvevi marta Stegagnini Lorenzo Andrea Coltro Pietro Invernizzi Division of Gastroenterology Fondazione IRCCS San Gerardo dei TintoriUniversity of Milano-BicoccaSchool of MedicineMonza 20900Italy

BACKGROUND The incidence of type I gastric neuroendocrine neoplasms(gNENs)has increased significantly over the past 50 *** autoimmune gastritis(AIG)increases the likelihood of developing gNENs,the exact incidence and prevalence of this association remain *** To evaluate the incidence and prevalence of type I gNENs in a cohort of patients with a histological diagnosis of *** Patients with a histological diagnosis of AIG were enrolled between October 2020 and May *** levels of CgA and gastrin were assessed at *** patients underwent regular endoscopic follow-up to detect gastric neoplastic lesions,enterochromaffin-like(ECL)cell hyperplasia,and the development of *** We included 176 patients[142 women(80.7%),median age 64 years,interquartile range(IQR)53–71 years]diagnosed with AIG between January 1990 and June *** *** hundred and sixteen patients(65.9%)had ECL hyperplasia,of whom,29.5%had simple/linear,30.7%had micronodular,and 5.7%had macronodular *** median follow-up time was 5(3–7.5)*** 1032 person-years,33 patients developed a total of 50 type I gNENs,with an incidence rate of 0.057 person-years,corresponding to an annual cumulative incidence of 5.7%.Circulating CgA levels did not significantly differ between AIG patients who developed gNENs and those who did ***,gastrin levels were significantly higher in AIG patients who developed gNENs[median 992 pg/mL IQR=449–1500 vs 688 pg/mL IQR=423–1200,P=0.03].Calculated gastrin sensitivity and specificity were 90.9%and 1.4%,respectively,with an overall diagnostic accuracy of 30%and a calculated area under the gastrin receiver operating characteristic curve(AUROC or AUC)of *** Type I gNENs are a significant complication in ***’s low diagnostic accuracy prevents it from serving as a marker for early *** strategies for early detection and treatment are needed.

关键词： Atrophic gastritis Autoimmune gastritis Gastrin Gastric neuroendocrine tumors

Oral Cadmium Intake Enhances Contact Allergen-induced Skin Reaction in Rats

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Biomedical and Environmental Sciences 2022年第11期35卷 1038-1050页

作者： Dina Tucovic Jelena Kulas Ivana Mirkov Dusanka Popovic Lidija Zolotarevski marta Despotovic Milena Kataranovski Aleksandra Popov Aleksandrov Immunotoxicology Group Department of EcologyInstitute for Biological Research"Sinisa Stankovic"-National Institute of Republic of SerbiaUniversity of Belgrade142 Bulevar despota Stefana11060 BelgradeSerbia Medical College of Applied Sciences 254 Cara Dusana11080 BelgradeSerbia Centre of Research Excellence in Nutrition and Metabolism Institute for Medical ResearchUniversity of Belgrade11 Tadeusa Koscuska 111000 BelgradeSerbia

Objective The effect of oral cadmium(Cd)intake to influence contact skin allergies was examined,since it is known that Cd is a heavy metal that affects many tissues,including the skin,in which it disturbs homeostasis,thus resulting in inflammation and *** Male rats were evoked with experimental contact hypersensitivity reaction(CHS)to hapten dinitrochlorobenzene(DNCB),after prolonged(30 day)oral exposure to an environmentally relevant Cd dose(5 ppm).The ear cell population was analyzed with flow *** production by ear skin cells and the activity of skin-draining lymph node(DLN)cells were measured using enzyme-linked immunosorbent assay(ELISA).Results Orally acquired Cd(5 ppm)increased CHS intensity only in Dark Agouti(DA)rats by affecting inflammatory responses in both the sensitization(an increase of IFN-γ and IL-17 cytokine production)and challenge(an increase of CD8^(+)and CD4^(+)cell number and TNF,IFN-γ and IL-17 cytokine production)*** increased CHS reaction was seen in Albino Oxford(AO)rats only at a high Cd dose(50 ppm),during the challenge phase(an increase of CD8^(+)and CD4^(+)cell number and TNF,IFN-γ and IL-17 cytokine production).Conclusion These novel data indicate that oral Cd intensifies the skin response to sensitizing chemicals such as DNCB.

关键词： Cadmium(Cd) Contact hypersensitivity reaction(CHS) Dinitrochlorobenzene(DNCB)

Open-porous magnesium-based scaffolds withstand in vitro corrosion under cyclic loading:A mechanistic study

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Bioactive Materials 2023年第1期19卷 406-417页

作者： Roxane Bonithon Colin Lupton marta Roldo Joseph Nicholas Dunlop Gordon William Blunn Frank Witte Gianluca Tozzi Zeiss Global Centre School of Mechanical and Design EngineeringUniversity of PortsmouthAnglesea RoadPO13DJPortsmouthUnited Kingdom School of Pharmacy and Biomedical Sciences University of PortsmouthWhite Swan RoadPO12DTPortsmouthUnited Kingdom School of the Environment Geography&GeosciencesUniversity of PortsmouthBurnaby RoadPO13QLPortsmouthUnited Kingdom Department of Prosthodontics Geriatric Dentistry and Craniomandibular DisordersCharite-Universitätsmedizin BerlinAßmannshauser Straße 4-614197BerlinGermany Biotrics Bioimplants AG Ullsteinstr.10812109BerlinGermany

The successful application of magnesium(Mg)alloys as biodegradable bone substitutes for critical-sized defects may be comprised by their high degradation rate resulting in a loss of mechanical *** study investigates the degradation pattern of an open-porous fluoride-coated Mg-based scaffold immersed in circulating Hanks’Balanced Salt Solution(HBSS)with and without in situ cyclic compression(30 N/1 Hz).The changes in morphological and mechanical properties have been studied by combining in situ high-resolution X-ray computed tomography mechanics and digital volume *** in situ cyclic compression induced acceleration of the corrosion rate,probably due to local disruption of the coating layer where fatigue microcracks were formed,no critical failures in the overall scaffold were observed,indicating that the mechanical integrity of the Mg scaffolds was *** changes,due to the accumulation of corrosion debris between the scaffold fibres,resulted in a significant increase(p<0.05)in the material volume fraction from 0.52±0.07 to 0.47±0.03 after 14 days of ***,despite an increase in fibre material loss,the accumulated corrosion products appear to have led to an increase in Young’s modulus after 14 days as well as lower third principal strain(εp3)accumulation(-91000±6361μεand-60093±2414μεafter 2 and 14 days,respectively).Therefore,this innovative Mg scaffold design and composition provide a bone replacement,capable of sustaining mechanical loads in situ during the postoperative phase allowing new bone formation to be initially supported as the scaffold resorbs.

关键词： Magnesium alloys Bone regeneration In vitro corrosion X-ray computed tomography(XCT) Digital volume correlation(DVC)

Acid-mediated decarboxylative C–H coupling between arenes and O-allyl carbamates

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Organic Chemistry Frontiers 2022年第6期9卷 1711-1718页

作者： Camilla Loro Julie Oble Francesca Foschi marta Papis Egle MBeccalli Sabrina Giofrè Giovanni Poli Gianluigi Broggini Dipartimento di Scienza e Alta Tecnologia Universitàdegli Studi dell’Insubriavia Valleggio 922100 ComoItaly Sorbonne Université Facultédes Sciences et IngénierieCNRSInstitut Parisien de Chimie MoléculaireIPCM4 place Jussieu75005 ParisFrance DISFARM Sezione di Chimica Generale e Organica“A.Marchesini”Universitàdegli Studi di Milanovia Venezian 2120133 MilanoItaly

Treatment of O-allyl N-tosyl carbamates with aromatic compounds in the presence of Cu(OTf)_(2) or TMSOTf as promoters affords N-substituted 1-arylpropan-2-amines,1,2-diarylpropanes,1,1-diarylpropanes,or indanes,depending on the nature of the promoter and of the aryl substrates.A full mechanistic rational allowing appreciation of the outcome of these novel C–H based cascades is *** initial acid promoted decarboxylative/deamidative Friedel–Crafts allylation takes *** protonation of the allylated arene,evolution of the resulting cation may follow different paths depending on the nature of the arene partner and of the allyl moiety in the carbamate.

关键词： allyl moiety coupling

Antimicrobial potential of aqueous coffee extracts against pathogens and Lactobacillus species:A food matrix application

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Food Bioscience 2022年第3期47卷 1142-1149页

作者： Luiza Andrea Canci marta de Toledo Benassi Cristiane Canan Daneysa Lahis Kalschne Eliane Colla Departamento de Alimentos Universidade Tecnológica Federal do ParanáAvenida Brasil4232Bairro Independência85884-000MedianeiraPRBrazil Centro de Ciências Agrárias Universidade Estadual de LondrinaRodovia Celso Garcia Cid PR 445 Km 38086057-970LondrinaParanáBrazil

Coffee is recognized by its bioactive potential,mainly antioxidant and antimicrobial *** aim of this study was to evaluate the antimicrobioal potential of aqueous extracts of Coffea arabica(AR)(roasted)and Coffea canephora[roasted(CR)and green(CG)]against patogens Salmonella Typhimurium and Escherichia coli,and probiotics Lactobacillus plantarum and Lactobacillus ***,the strain's sensitivity were tested by disk diffusion method,followed by the evaluation of growth kinetics(lag phase duration,maximum specific growth rate and logarithmic increase in the population)in culture media and in a food matrix(milk)by the adjustment of Gompertz predictive *** the step of strain sensivity tests,*** and *** were sensitive against all coffee extracts from 0.5%to 5.0%,while the Lactobacilli growth were not *** the growth kinetic tests in culture media,roasted coffees extracts reduced logarithmic increase in the population and maximum specific growth rate and improved lag phase for ***;for *** the growth was completely inhibited with 2.5%CR and 5.0%*** correlations between growth parameters with coffee bioactive contents suggested that melanoidins had the main antimicrobial *** the step of food matrix application(growth kinetics in milk),the addition of 5.0%CR reduced *** and *** multiplication,while the probiotics *** and *** where not inhibetd,suggesting a selective effect of coffee extracts as an antimicrobial agent,which may be of great interest for the food industry,especially for probiotic foods application.

关键词： Coffea arabica Coffea canephora Escherichia coli Green coffee Roasted coffee Salmonella Typhimurium

Impact of laser chirp on the polarization of terahertz from two-color plasma

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Photonics Research 2023年第6期11卷 978-985页

作者： SEN MOU LUCA TOMARCHIO ANNALISA D’ARCO marta DI FABRIZIO SALVATORE MACIS ALESSANDRO CURCIO LUIGI PALUMBO STEFANO LUPI MASSIMO PETRARCA INFN-Roma1 and Physics Department University of Rome“La Sapienza”00185 RomeItaly Physics Department University of Rome“La Sapienza”00185 RomeItaly SBAI Department of Basic and Applied Sciences for EngineeringUniversity of Rome“La Sapienza”00161 RomeItaly Centro de Laseres Pulsados(CLPU) 37185 VillamayorSalamancaSpain INFN-LNF 00044 FrascatiItaly

Two-color plasma,induced by two lasers of different colors,can radiate ultra-broadband and intense terahertz(THz)pulses,which is desirable in many technological and scientific *** was found that the polarization of the emitted THz depends on the phase difference between the fundamental laser wave and its second *** investigation suggests that chirp-induced change of pulse overlap plays an important role in the THz yield from two-color ***,the effect of laser chirp on THz polarization remains ***,we investigate the impact of laser chirp on THz *** is unveiled that the chirp-induced phase difference affects THz ***,positive and negative chirps have opposite effects on the variation of the THz polarization versus the phase *** polarization of THz generated by a positively chirped pump laser rotates clockwise with an increasing phase difference,while it rotates anticlockwise when generated by a negatively chirped pump laser.

关键词： polarization laser pump

Isotopic niche provides an insight into the ecology of a symbiont during its geographic expansion

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Current Zoology 2022年第2期68卷 185-197页

作者： Enrique GONZALEZ-ORTEGON marta PEREZ-MIGUEL Jose I.NAVAS Pilar DRAKE Jose A.CUESTA Instituto de Ciencias Marinas de Andalucia(ICMAN-CSIC) Campus Universitario Rio San PedroAvda.Republica Saharaui211519CadizPuerto RealSpain Unidad Asociada Crecimiento Azul CSIC-IFAPA El Puerto de Santa Maria SpainSpain Instituto de Investigacion y Formacion Agraria y Pesquera IFAPA-Centro Agua del PinoCtra.EI Rompido-Punta Umbriakm 3.821459 EI RompidoHuelvaSpain

The study of the recent colonization of a symbiont and its interaction with host communities in new locations is an opportunity to understand how they *** use of isotopic ratios in trophic ecology can provide measurements of a species'isotopic niche,as well as knowledge about how the isotopic niches between symbiont and host species *** isotope measurements were used to assess the sources of carbon assimilated by the host species(the bivalves Mytilus galloprovincialis and Scrobicularia plana)and their associated symbiont pea crab Afropinnotheres monodi,which occurs within these bivalves'mantle *** mixing model estimates suggest that all of them assimilate carbon from similar sources,particularly from pseudofaeces and particulate organic matter in this symbiotic system based on filter *** symbiotic species occupy comparable trophic levels and its association seems to be commensal or parasitic depending on the duration of such *** pea crab *** reflects a sex-specific diet,where males are more generalist than the soft females because the latter's habitat is restricted to the host *** high isotopic overlap between soft females and *** may reflect a good commensal relationship with the host.

关键词： bivalves commensal kleptoparasitism parasitism stable isotope trophic position

Narrative Medicine in China and Chinese Sources for Narrative Medicine

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Chinese Medicine and Culture 2023年第2期6卷 125-126页

作者： marta Hanson Independent scholar Affiliate Max Planck Institute for the History of ScienceBerlin 14195Germany

In 2001,internist and literary scholar Rita Charon at Columbia University famously announced a new discipline called narrative *** based it on the premise that the basic humanistic skills of critical reading,slow looking,and reflective writing were as necessary for developing clinical skills as evidence-based medical *** by 2011,the new discipline of narrative medicine had taken root in China through published articles and a meeting at the Institute for Medical Humanities(now School of Health Humanities)in Peking *** a decade later,narrative medicine programs have not only proliferated in medical schools and hospitals across China but they have also developed into novel programs of“narrative medicine with Chinese characteristics.”

关键词： looking Just premise