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中新世气候适宜期构造运动加速全球海洋碳循环

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Science Bulletin 2024年第6期69卷 823-832页

作者：刘丰豪杜金龙黄恩清马文涛马小林 lucas J.Lourens 田军 State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Department of Earth Sciences Faculty of GeosciencesUtrecht UniversityUtrecht CB 3584Netherlands

Global warming during the Miocene Climate Optimum(MCO,~17-14 million years ago)is associated with massive carbon emissions sourced from the flood basalt volcanism and ocean crustal ***,the perturbation of tectonic carbon degassing on the interaction between climate change and carbon cycle remains ***,through time-evolutive phase analysis of new and published high-resolution benthic foraminiferal oxygen(δ^(18)O)and carbon(δ^(13)C)isotope records from the global ocean,we find that variations in the marine carbon cycle lead the climate-cryosphere system(δ^(13)Clead-δ^(18)O)on 405,000-year eccentricity timescales during the *** is in contrast to the previously reported climate-lead-carbon(δ^(18)O-lead-δ^(13)C)scenario during most of the Oligo-Miocene(~34-6 million years ago).Further sensitivity analysis and model simulations suggest that the elevated atmospheric CO_(2) concentrations and the resulting greenhouse effect strengthened the low-latitude hydrological cycle during the MCO,accelerating the response of marine carbon cycle to eccentricity *** climate processes played a more important role in regulating carbon-cycle variations when Earth's climate was in a warm regime,as opposed to the dominant influence of polar ice-sheet dynamics during the PlioPleistocene(after~6 million years ago).

关键词： Global warming Eccentricity cycle Carbon cycle Low-latitude hydrological cycle

High-speed silicon photonic electro-optic Kerr modulation

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Photonics Research 2024年第1期12卷 51-60页

作者： JONATHAN PELTIER WEIWEI ZHANG LEOPOLD VIROT CHRISTIAN LAFFORGUE lucas DENIEL DELPHINE MARRIS-MORINI GUY AUBIN FARAH AMAR DENH TRAN XINGZHAO YAN CALLUM G.LITTLEJOHNS CARLOS ALONSO-RAMOS KE LI DAVID J.THOMSON GRAHAM REED LAURENT VIVIEN University Paris-Saclay CNRSCentre for Nanoscience and Nanotechnology(C2N)Palaiseau 91120France University Grenoble Alpes CEALETIGrenoble 38000France Optoelectronics Research Centre Zepler Institute for Photonics and NanoelectronicsFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

Silicon-based electro-optic modulators contribute to easing the integration of high-speed and low-power consumption circuits for classical optical communications and data *** the plasma dispersion modulation,an alternative solution in silicon is to exploit the DC Kerr effect,which generates an equivalent linear electro-optical effect enabled by applying a large DC electric *** some theoretical and experimental studies have shown its existence in silicon,limited contributions relative to plasma dispersion have been achieved in high-speed modulation so *** paper presents high-speed optical modulation based on the DC Kerr effect in silicon PIN *** contributions of both plasma dispersion and Kerr effects have been analyzed in different waveguide configurations,and we demonstrated that the Kerr induced modulation is dominant when a high external DC electric field is applied in PIN ***-speed optical modulation response is analyzed,and eye diagrams up to 80 Gbit/s in NRZ format are obtained under a *** of 30 *** work paves the way to exploit the Kerr effect to generate high-speed Pockels-like optical modulation.

关键词： waveguide dispersion effect

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用正交光电二极管更快地对焦

科技纵览 2024年第3期 10-11页

作者： lucas Laursen 不详

在2013年,佳能推出了其第一款双像素自动对焦相机,这项技术可使光敏传感器的每个像素都帮助拍摄图片对焦。现在,佳能的研究人员表示,他们已经改进了先前的自动对焦技术。这种新方法对焦速度快、质量好,可用于低光线场景,而且不需要先发... 详细信息

在2013年,佳能推出了其第一款双像素自动对焦相机,这项技术可使光敏传感器的每个像素都帮助拍摄图片对焦。现在,佳能的研究人员表示,他们已经改进了先前的自动对焦技术。这种新方法对焦速度快、质量好,可用于低光线场景,而且不需要先发明新的组件和技术。它只涉及一个小小的“扭曲”。

关键词：光敏传感器光电二极管对焦佳能像素光线自动对焦相机

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巴黎奥运会启用人工智能视频监控

科技纵览 2024年第1期 34-37,4页

作者： lucas Laursen 不详

2022年冬奥会期间,滑雪运动员在北京郊外的滑雪公园里滑行转弯时,有些人可能注意到了沿途的一串铁塔。那些铁塔采集整个光谱的波长,而且会搜寻数据以发现可疑活动的迹象,是基于物联网的监控系统的一部分。

关键词：智能视频监控奥运会物联网监控系统滑雪铁塔

Experimental evidence of pressure effects on spinel dissolution and peridotite serpentinization kinetics under shallow hydrothermal conditions

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Geoscience Frontiers 2024年第2期15卷 236-250页

作者： Yuri de Melo Portella Rommulo Vieira Conceição Tiago Abreu Siqueira lucas Bonan Gomes Rodrigo Sebastian Iglesias Programa de Pós-Graduação em Geociências(PPGGEO) Universidade Federal do Rio Grande do SulPorto AlegreBrazil Petrobras–Petróleo Brasileiro S.A. Avenida Henrique Valadares 28CentroRio de Janeiro(RJ)20231-030Brazil Instituto do Petróleo e dos Recursos Naturais-PUCRS–Pontifícia Universidade Católica do Rio Grande do Sul 90619-900Porto AlegreBrazil Universidade Federal do Rio Grande do Sul Instituto de GeociênciasLaboratório de Difratometria de Raios XPorto AlegreBrazil escola Politécnica–PUCRS-Pontifícia Universidade Católica do Rio Grande do Sul 90619-900 Porto AlegreBrazil

Serpentinization reactions are paramount to understand hydro-geothermal activity near plate boundaries and mafic–ultramafic massifs,as well as fluid and element transfer between the Earth’s mantle and ***,fluid-rock element exchange and serpentinization kinetics under shallow hydrothermal conditions is still largely *** we present two constant temperature(230℃)time-series of natural peridotite(77.5%olivine;13.7%enstatite;6.8%diopside;2%spinel)serpentinization experiments:at 13.4 MPa;and 20.7 ***-enriched lizardite was the main secondary mineral in all runs after olivine(olv)and orthopyroxene(opx)serpentinization(without any detectable brucite,talc or magnetite),while primary spinel and diopside partially dissolved during the *** serpentinization stages comprises intrinsically coupled reactions between olivine and enstatite,as Al and Si are progressively transferred from orthopyroxene-derived to olivine-derived serpentine,while the opposite is true for Mg and Fe,with homogenization of serpentines compositions after 40 *** Ni/Cr ratios of serpentines,however,remain diagnostic of the respective primary *** average serpentine content indicates fast serpentinization rates of 0.55 wt.%·day^(-1)(0.26 mmol·day^(-1))and 0.26 wt.%·day^(-1)(0.13 mmol·day^(-1))at 13.4 and 20.7 MPa,*** 2x faster serpentinization kinetics at lower pressure is likely linked to enhanced spinel dissolution leading to one order of magnitude higher available Al,which accelerates olivine serpentinization while delays orthopyroxene ***,time-dependent increase in solid products masses suggests rock volume expands linearly 0.37%±0.01%per serpentine wt.%independently of *** balance constrains suggests olv:opx react at~5:2 and~3:2 M ratios,resulting in Si-deficient and Si-saturated serpentines at the end of the low-pressure series(13.4 MPa)and high-pressure series(20.7 MPa),***

关键词： Serpentine Volume expansion Serpentinization fluids Lost City hydrothermal field Serpentinite-hosted hydrothermal systems Hydrogen(H_(2))generation

Congophilic fibrils in the glomeruli with polyclonal immunoglobulin gamma staining-another cause for diagnostic overlap:A case report

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World Journal of Clinical Cases 2024年第17期12卷 3200-3205页

作者： Maria Bernadette Che-Ying Chow lucas Bushrow Irmeen Siddiqui April Chiu Mirza Hamirani Anjali A Satoskar Department of Pathology The Ohio State University Medical CenterColumbusOH 43210United States Department of Pathology North District HospitalSheung ShuiHong KongChina Department of Laboratory Medicine and Pathology Mayo ClinicRochesterMN 55905United States Department of Internal Medicine S.Joseph's HospitalParkersburgWV 26101United States

BACKGROUND Glomerulopathy with fibrillary deposits is not uncommon in routine nephropathology practice,with amyloidosis and fibrillary glomerulonephritis being the two most frequently encountered *** amyloid heavy and light chain(AHL)is relatively uncommon and its biopsy diagnosis is usually limited to cases that show strong equivalent staining for a single immunoglobulin(Ig)heavy chain and a single light chain,further supported by mass spectrometry(MS)and serum studies for monoclonal *** polyclonal light chain staining can pose a *** SUMMARY Herein we present a challenging case of renal AHL with polyclonal and polytypic Ig gamma(IgG)staining pattern by *** patient is a 62-yearold Caucasian male who presented to an outside institution with a serum creatinine of up to 8.1 mg/dL and nephrotic range *** the finding of a polyclonal and polytypic staining pattern on immunofluorescence,ultrastructural study of the renal biopsy demonstrated the presence of fibrils with a mean diameter of 10 *** red was positive while DNAJB9 was *** suggested a diagnosis of amyloid AHL type with IgG and lambda,but kappa light chains were also present supporting the immunofluorescence staining *** immunofixation studies demonstrated IgG lambda monoclonal *** patient was started on *** chronic renal injury however was quite advanced and he ended up needing dialysis shortly *** Tissue diagnosis of AHL amyloid can be *** confirmation using other available diagnostic techniques is recommended in such cases.

关键词： Heavy and light chain amyloid Fibrillary glomerulonephritis DNAJB9 Serum immunofixation Protein electrophoresis Mass spectrometry Congo red Case report

Analysis of Perinatal Outcomes of Twin Pregnancy in a Referral Hospital for High Risk

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Open Journal of Obstetrics and Gynecology 2024年第7期14卷 983-995页

作者： Eduarda Paim Pedro lucas Carneiro Ferreira Luciano Selistre Fernanda Grossi José Mauro Madi Gabriela Françoes Rostirolla Mdica Residente do Programa de Residncia em Ginecologia e Obstetrcia Hospital Geral de Caxias do Sul Rio Grande do Sul Brasil Faculdade de Medicina Universidade de Caxias do Sul Rio Grande do Sul Brasil Programa de Ps-Graduao Universidade de Caxias do Sul Rio Grande do Sul Brasil Servio de Ginecologia e Obstetrcia Hospital Geral de Caxias do Sul Rio Grande do Sul Brasil

Introduction: The incidence of twin pregnancies has increased significantly in recent decades. These pregnancies require more attention due to their worse outcomes than singleton pregnancies. Objective: To analyze the characteristics and perinatal outcomes of twin pregnancies at the Caxias do Sul General Hospital. Methods: This is a descriptive and retrospective study that included all births related to twin pregnancies between March 1998 and June 2018. Maternal and perinatal variables were analyzed. Descriptive analyses were carried out using measures of central tendency and dispersion for continuous variables (mean and standard deviation or median and interquartile range), according to a prior assessment of distribution using the Shapiro-Wilk test, and absolute (n) and relative (n%) frequencies for categorical variables. Results: 172 pairs of twins/21,972 births (0.8%) were identified. There was a high percentage of interpartum interval of less than 12 months, adherence and prenatal visits, body mass index, and need for neonatal intensive care. Stillbirth and neomortality rates were within acceptable parameters. Conclusion: The sample studied showed a percentage similar to that in the literature, a high rate of maternal and perinatal complications, characterizing it as a high-risk fetal pregnancy.

关键词： Pregnancy Twin Pregnancy High Risk Pregnancy Morbidity Perinatal Mortality Perinatal Results

Delay Times and Clinical Outcomes in Acute Myocardial Infarction: Comparison of Periods before and during the COVID-19 Pandemic—Myocardial Infarction and the Pandemic

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World Journal of Cardiovascular Diseases 2024年第6期14卷 392-400页

作者： Clarice Teixeira Silva Araújo Arnon Salviato Mameri Thúlio Carrera Guarçoni Venturini Marcus Tadeu Aguilar Constantino Matos Igor Morais Araujo Lopes Luiz Gustavo Ribeiro de Carvalho Murad Cleberson Duartes Ovani Guilherme Vassalo Morais Fernanda Venturini de Castro Danielle Lopes Rocha lucas Crespo de Barros Rodolfo Costa Sylvestre Luiz Fernando machado Barbosa Roberto Ramos Barbosa Internal Medicine Universidade Federal do Esprito Santo (UFES) Vitria Brazil Hospital Santa Casa de Misericrdia de Vitria Vitria Brazil Hospital Santa Rita de Cssia Vitria Brazil Hospital estadual Dr. Jayme Santos Neves Serra Brazil Grupo Kora Sade Vitria Brazil Hospital estadual Infantil e Maternidade Alzir Bernardino Alves (HIMABA) Vila Velha Brazil

Introduction: At the beginning of the COVID-19 pandemic, a drop in the number of patients treated for cardiac emergencies raised concern about cardiovascular mortality in that period. An increase in care delay for patients with ST-segment elevation myocardial infarction (STEMI) may have affected clinical outcomes. Objectives: To analyze delay times and clinical outcomes of patients with STEMI undergoing primary percutaneous coronary intervention (PPCI), before and during the COVID-19 pandemic. Methods: Retrospective observational study that included patients with STEMI undergoing PPCI from December 2018 to July 2021. The COVID-19 pandemic cases were divided into two groups: pandemic I—from March to August 2020;and pandemic II—from September 2020 to July 2021. Patients were compared according to the period of hospitalization. Primary outcomes were delay times in assistance and clinical outcomes (acute kidney injury [AKI], post-procedural vascular complications and in-hospital mortality). Results: 108 patients were included, 39 (36.1%) in the pre-pandemic period, 13 (12.1%) in pandemic I and 56 (51.8%) in pandemic II. Time from onset of symptoms to arrival at the service and door-to-balloon time did not differ significantly among groups. Vascular complications were more frequent during the pandemic (I and II) than in the pre-pandemic period (2.5% pre-pandemic vs 15.4% pandemic vs 12.5% pandemic II;p = 0.03). AKI incidence was similar in all three periods. There was a non-significant increase in in-hospital mortality during the COVID-19 pandemic. Conclusion: In patients with STEMI, there was an increase in vascular complications and a trend toward increased mortality during the COVID-19 pandemic. Delay times to admission and reperfusion did not differ significantly between before and during the pandemic.

关键词： Myocardial Infarction Primary Percutaneous Coronary Intervention Coronary Reperfusion Pandemic COVID-19

Solar-driven CO_(2) conversion to methane and methanol using different nanostructured Cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy Chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima Perini Lilian D.Moura Torquato Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves Leonardo D.De Angelis lucas D.Germano Susana I.Córdoba de Torresi Teodorico C.Ramalho Maria V.Boldrin Zanoni São Paulo State University(UNesP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National Institute of Alternative Technologies for Detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil Department of Chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TNT@PDA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be Cu_(2)O facet-dependent,with cubic structures leading to greater conversion of CO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)O surface was mainly important for *** functional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PDA/Nc/Au40%electrode for CH4generation to the formation of an OCH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(GC-MS)demonstrated that13CO_(2)was the source for photoelectrocatalytic generation of13CH3OH and13CH313CH2OH.

关键词： Cu_(2)O nanocubes Photoelectrocatalysis Polydopamine CO_(2) photoelectroreduction DFT calculations