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A great thermal divergence in the mantle beginning 2.5 Ga:Geochemical constraints from greenstone basalts and komatiites

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Geoscience frontiers 2016年第4期7卷 543-553页

作者： Kent C.Condie Richard C.Aster Jeroen van Hunen department of Earth and Environmental Science New Mexico Tech Geosciences department Colorado State University department of Earth sciences University of Durham

Greenstone basalts and komatiites provide a means to track both mantle composition and magma generation temperature with time. Four types of mantle are characterized from incompatible element distributions in basalts and komatiites： depleted, hydrated, enriched and mantle from which komatiites are derived. Our most important observation is the recognition for the first time of what we refer to as a Great Thermal Divergence within the mantle beginning near the end of the Archean, which we ascribe to thermal and convective evolution. Prior to 2.5 Ga, depleted and enriched mantle have indistinguishable thermal histories, whereas at 2.5-2.0 Ga a divergence in mantle magma generation temperature begins between these two types of mantle. Major and incompatible element distributions and calculated magma generation temperatures suggest that Archean enriched mantle did not come from mantle plumes, but was part of an undifferentiated or well-mixed mantle similar in composition to calculated primitive mantle. During this time, however, high-temperature mantle plumes from dominantly depleted sources gave rise to komatiites and associated basalts. Recycling of oceanic crust into the deep mantle after the Archean may have contributed to enrichment ofTi, A1, Ca and Na in basalts derived from enriched mantle sources. After 2.5 Ga, increases in Mg# in basalts from depleted mantle and decreases in Fe and Mn reflect some combination of growing depletion and cooling of depleted mantle with time. A delay in cooling of depleted mantle until after the Archean probably reflects a combination of greater radiogenic heat sources in the Archean mantle and the propagation of plate tectonics after 3 Ga.

关键词： Archean greenstones Mantle thermal evolution Basalts Mantle geochemistry Komatiites

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Pediatric flexible flatfoot: Does obesity influence the outcomes of arthroereisis?

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World Journal of Orthopedics 2024年第9期15卷 850-857页

作者： Luca Monestier Giacomo Riva Mahfuz Latiff Luca Marciandi Elisa Bozzi Alessandra Pelozzi Andrea Pautasso Giorgio Pilato Michele Francesco Surace Fabio D'Angelo Division of Orthopedics and Traumatology ASST Sette LaghiVarese 21100LombardyItaly Residency Program in Orthopedics and Trauma Department of Biotechnologies and Life SciencesUniversity of InsubriaVarese 21100LombardyItaly Interdisciplinary Research Centre for Pathology and Surgery of the Musculoskeletal System Department of Biotechnology and Life SciencesUniversity of InsubriaVarese 21100LombardyItaly Division of Orthopedics and Traumatology Ospedale di CittiglioASST Sette LaghiVarese 21100LombardyItaly

BACKGROUND Childhood obesity has emerged in the last decades as an important public health problem *** relationships between obesity and flatfoot have been shown,no studies have investigated the influence of obesity on arthroereisis *** To evaluate correlations between childhood overweight/obesity and clinical and radiographic outcomes after subtalar arthroereisis with self-locking *** This retrospective study included one hundred and sixty-nine pediatric patients(10-14 years old)who underwent subtalar arthroereisis(PEEK PitStop®device)for severe flexible *** criteria were additional procedures,revision of previous corrective surgeries,rigid flatfoot with severe deformity,and neurologi-cal or post-traumatic ***/postoperative European Foot and Ankle Society(EFAS)and visual analogue scale(VAS)scores were determined;radiographic assessment was conducted on weight-bearing foot X-rays:Kite angle,first metatarsal-talus angle,Meary angle,calcaneal pitch angle and lateral talo-calcaneal angle were *** EFAS and VAS scores improved post-operatively in the whole *** seven cases with complications were *** assessment revealed an improvement in all *** analysis demonstrated that the impact of obesity was significant on arthroereisis outcomes:Relationships were reported between BMI and postoperative EFAS/VAS scores,postoperative calcaneal pitch angle,Kite angle,Meary angle and talo-first meta-tarsal *** Although arthroereisis represents a very effective and valid treatment for flatfoot both in normal weight and obese children,obesity significantly influences clinical and radiographic outcomes of arthroereisis,and obese children tend to perceive more pain and discomfort.

关键词： Pediatric flatfoot Obesity Subtalar Arthroereisis Outcomes

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Oxygen self-doping pyrolyzed polyacrylic acid as sulfur host with physical/chemical adsorption dual function for lithium-sulfur batteries

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Chinese Chemical Letters 2024年第7期35卷 473-479页

作者： Yan Wang Huixin Chen Fuda Yu Shanyue Wei Jinhui Song Qianfeng He Yiming Xie Miaoliang Huang Canzhong Lu Engineering Research Center of Environment-Friendly Functional Materials Ministry of EducationInstitute of Materials Physical ChemistryHuaqiao UniversityXiamen 361021China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen 361021China

Lithium-sulfur(Li-S)batteries with high theoretical capacity and energy density need to solve problems such as the high decomposition energy barrier of Li_(2)S and large volume change of sulfur in the charging process caused by the shuttle effect before practical ***,a green synthesis method is used to prepare polyacrylic acid(PAA)superabsorbent material,and then the pyrolyzed PAA(P/PAA)material is obtained as the positive electrode of Li-S *** functional calculation reveals that the oxygen self-doping pyrolyzed polyacrylic acid(P/PAA)delivered stronger binding energy toward Li2S species in carbonyl C=O than that of graphite powder(GP)which are-1.58 eV and-1.02 eV,*** with the distribution of relaxation time analysis and the in-situ electrochemical impedance approach,it is further demonstrated that the designed P/PAA as sulfur host plays a physical/chemical adsorption dual function in maintaining the stability and rate performance of *** an initial discharge capacity of 1258 mAh/g at 0.1 C and a minimal capacity decline of 0.05%per cycle even after 800 cycles at 0.5 C,the produced cathode demonstrated outstanding electrochemical *** average Coulombic efficiency is nearly 100%.The P/PAA electrodes may typically retain 96%of their capacity while declining on average only 0.033%per cycle after 130 cycles at 3 *** effort provides a new method for the future development of heteroatomic self-doping superabsorbent with promising adsorption properties for polysulfides as cathode materials of Li-S batteries.

关键词： Polyacrylic acid Oxygen self-doping Green synthetic Pore mesh polymer cathodes Lithium-sulfur batteries

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Dual-symmetry-perturbed all-dielectric resonant metasurfaces for high-Q perfect light absorption

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Chinese Optics Letters 2024年第2期22卷 200-206页

作者：葛俊洋高一骁徐雷周宁沈祥 Laboratory of Infrared Materials and Devices Research Institute of Advanced TechnologiesNingbo UniversityNingbo 315211China Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo 315211China Advanced Optics&Photonics Laboratory Department of EngineeringSchool of Science and TechnologyNottingham Trent UniversityNottingham NG118NSUK School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Ningbo Institute of Oceanography Ningbo 315832China

We demonstrate a high-Q perfect light absorber based on all-dielectric doubly-resonant *** bound states in the continuum(BICs)protected by different symmetries,we manage to independently manipulate the Q factors of the two degenerate quasi-BICs through dual-symmetry perturbations,achieving precise matching of the radiative and nonradiative Q factors for degenerate critical *** achieve a narrowband light absorption with a>600 Q factor and a>99%absorptance atλ_(0)=1550 nm on an asymmetric germanium metasurface with a 0.2λ_(0)*** work provides a new strategy for engineering multiresonant metasurfaces for narrowband light absorption and nonlinear applications.

关键词： resonant metasurface perfect light absorption bound states in the continuum

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Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO Javier PRECIADO-GARBAYO Jorge SEVIL Francisco GUTIERREZ Juan JMARTiNEZ Sonia MARTiN-LOPEZ Miguel GONZALEZ-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain department of Earth sciences Universidad de ZaragozaZaragoza 50009Spain department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

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通过从头算非绝热分子动力学研究1T-VSe_(2)中的光激发诱导自旋动力学

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Science China Materials 2024年第4期67卷 1253-1259页

作者：陈林杰郑镇法郑奇靖李群祥赵瑾 department of Chemical Physics School of ChemistryUniversity of Science and Technology of ChinaHefei 230026China department of Physics and ICQD/Hefei National Research Center for Physical sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China Key Laboratory of Precision and Intelligent Chemistry University of Science and Technology of ChinaHefei 230026China

利用光激发来操控二维材料中的磁矩是实现光自旋电子学器件的基础.本工作中,我们利用从头算非绝热分子动力学模拟,研究了光激发如何改变二维铁磁金属VSe_(2)中的磁矩.我们发现自旋-轨道耦合作用和声子激发导致了自旋向上和自旋向下电子... 详细信息

利用光激发来操控二维材料中的磁矩是实现光自旋电子学器件的基础.本工作中,我们利用从头算非绝热分子动力学模拟,研究了光激发如何改变二维铁磁金属VSe_(2)中的磁矩.我们发现自旋-轨道耦合作用和声子激发导致了自旋向上和自旋向下电子态发生混合,并在费米能级以上1.0 eV附近形成了一个自旋混合区.当自旋向上或向下的电子在弛豫过程中经过这个混合区时,它们会丢失原有的自旋方向.当电子从费米面以上2.0 eV左右向下弛豫时,自旋向下的电子发生带内弛豫,而自旋向上的电子发生带间弛豫.因此,自旋向下电子的弛豫速度比自旋向上电子高出约一个数量级.这种自旋向上和自旋向下电子的动态行为差异导致了VSe_(2)的磁矩在光激发后10 fs内先增大,这对应了自旋向下电子失去了原始的自旋方向;随后,磁矩在100 fs内减小,这对应了自旋向上电子失去了原始自旋的方向;最后,系统的总磁矩在皮秒的时间尺度内逐渐恢复到光激发前的水平.这项工作为我们了解光激发如何操控二维材料的磁性提供了理论依据.

关键词：从头算弛豫过程费米面费米能级电子态自旋动力学二维材料非绝热

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Laser Wire Additive Manufacturing of Ti-6Al-4V Alloy and Its Machine Learning Study for Parameters Optimization(Invited)

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中国激光 2024年第4期51卷 182-198页

作者： Wu Junyi Zhang Bo Wang Weihua Li Weipeng Yao Xiyu Wang Dawei Xing Wei Yan Ming department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina Songshan Lake Materials Laboratory Dongguan 523830GuangdongChina Institute of Physics Chinese Academy of SciencesBeijing 100190China Jiaxing Research Institute Southern University of Science and TechnologyShenzhen 518055GuangdongChina High Performance Computing department National Supercomputing CenterShenzhen 518055GuangdongChina

Ti-6Al-4V is a benchmark Ti alloy. Laser wire additive manufacturing(LWAM) offers advanced manufacturing capability to the alloy for applications possibly including exploration of outer space. As a typical multiple-variable process, LWAM is complex, which, however, can be analyzed, predicated or even optimized by artificial intelligence(AI) methods such as machine learning(ML). In this study, printing parameters of the Ti-6Al-4V is firstly optimized using single-track-single-layer experiments, and then single-track-multiple-layer samples are printed, whose properties in terms of hardness and compressive strength are analyzed subsequently by both experiments and ML. The two ML approaches, artificial neural network(ANN) and support vector machine(SVM), are employed to predict the experimental results, whose coefficients of determination R2 show good values. Further optimized properties are realized by adopting genetic algorithm(GA) and simulated annealing(SA) approaches, which contribute to high mechanical properties achieved, for instance, an engineering compressive strength of about 1694 MPa. The results here indicate that important mechanical properties of the LWAM-prepared Ti alloys can be well predicted and enhanced using suitable ML approaches.

关键词： artificial printing additive

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An observed nocturnal ozone transport event in the Sichuan Basin,Southwestern China

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Journal of Environmental sciences 2024年第4期138卷 10-18页

作者： Ruyue Guo Guangming Shi Dan Zhang Yang Chen Chao Peng Chongzhi Zhai Fumo Yang department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China College of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China National Engineering Research Center on Flue Gas Desulfurization Chengdu 610065China Chongqing Academy of Eco-Environmental Science Chongqing 401147China Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Key Laboratory for Urban Atmospheric Environment Integrated Observation&Pollution Prevention and Control of Chongqing Chongqing 401147China

The ozone(O_(3))pollution in China drew lots of attention in recent years,and the Sichuan Basin(SCB)was one of the regions confronting worsening O_(3)pollution *** previous studies have shown that regional transport is an important contributor to O_(3)***,very few features of the O_(3)profile during transport have been reported,especially in the border regions between different administrative *** this study,we conducted tethered balloon soundings in SCB during the summer of 2020 and captured a nocturnal O_(3)transport event during the ***,the O_(3)transport occurred in the bottom of the residual layer,between 200 and 500 m above ground ***,the transport pathway was directed from southeast to northwest based on the analysis of the wind field and air mass *** effect of transport in the residual layer on the surface O_(3)concentration was related to the spatial distribution of O_(3).For cities with high O_(3)concentrations in the upwind region,the transport process would bring clean air masses and abate *** downwind lightly polluted cities,the transport process would slow down the decreasing or even increase the surface O_(3)concentration during the *** provided observational facts on the profile features of a transboundary O_(3)transport event between two provincial administrative divisions,which implicated the importance of joint prevention and control ***,the sounding parameters were limited and the quantitative analysis was preliminary,more integrated,and thorough studies of this topic were called for in the future.

关键词： Ozone Sichuan basin Transport event Vertical profile

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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model

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Journal of Magnesium and Alloys 2024年第1期12卷 384-393页

作者： Baoxiang Zhang Wen Zhang Fei Zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang Zhang department of Sports Medicine Chinese PLA General HospitalBeijing 100853China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Medical School of PLA Beijing 100853China Institute of Orthopedics Chinese PLA General HospitalBeijing Key Lab of Regenerative Medicine in OrthopedicsKey Lab of Musculoskeletal Trauma&War Injuries of Chinese PLABeijing 100853China

Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional *** the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as *** shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after *** Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to *** observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture *** the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks *** collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous *** vivo degradation of the magnesium alloy wire was completed within 12 *** results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair.

关键词： Rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface

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Adaptive ultra-hypofractionated whole-pelvic radiotherapy in high-risk and very high-risk prostate cancer on 1.5-Tesla MR-Linac:Estimated delivered dose and early toxicity results

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Chronic Diseases and Translational Medicine 2024年第1期10卷 51-61页

作者： Linrui Gao Ran Wei Shirui Qin Yuan Tian Wenlong Xia Yongwen Song Shulian Wang Hui Fang Yu Tang Hao Jing Yueping Liu Yuan Tang Shunan Qi Bo Chen Yexiong Li Nianzeng Xing Ningning Lu department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina GCP Center/Clinical Research Center National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina department of Urology State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background: Magnetic resonance(MR)-guided ultra-hypofractionated radiotherapy with whole-pelvic irradiation(UHF-WPRT)is a novel approach to radiotherapy for patients with high-risk(HR)and very high-risk(VHR)prostate cancer(PCa).However,the inherent complexity of adaptive UHF-WPRT might inevitably result in longer on-couch *** aimed to estimate the delivered dose,study the feasibility and safety of adaptive UHF-WPRT on a 1.5-Tesla ***: Ten patients with clinical stage T3a-4N0-1M0-1c PCa,who consecutively received UHF-WPRT,were enrolled *** contours of the target and organ-at-risks on the position verification-MR(PV-MR),beam-on 3D-MR(Bn-MR),and post-MR(after radiotherapy delivery)were derived from the pre-MR data by deformable image *** physician then manually adjusted them,and dose recalculation was performed *** Prism 9(GraphPad Prism Software Inc.)was utilized for conducting statistical ***: In total,we collected 188 MR scans(50 pre-MR,50 PV-MR,44 Bn-MR,and 44 post-MR scans).With median 59 min,the mean prostate clinical target volume(CTV)-V_(100%)was 98.59%±2.74%,and the mean pelvic CTVp-V_(100%)relative percentages of all scans was 99.60%±1.18%.The median V29 Gy change in the rectal wall was−2%(−18%to 20%).With a median follow-up of 9 months,no patient had acute Common Terminology Criteria for Adverse Events(CTCAE)grade 2 or more severe genitourinary(GU)or gastrointestinal(GI)toxicities(0%).Conclusion: UHF-RT to the prostate and the whole pelvis with concomitant boost to positive nodes using an Adapt-To-Shape(ATS)workflow was technically feasible for patients with HR and VHR PCa,presenting only mild GU and GI *** estimated target dose during the beam-on phase was clinically acceptable based on the 3D-MR-based dosimetry *** trial registration Chinese Clinical Trial Registry ChiCTR2000033382.

关键词： dosimetry hypofractionation magnetic resonance imaging prostate cancer radiation dose radiotherapy

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