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Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

Journal of forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina Dmitry R.Dergunov Mikhail S.Zharkov Liliana V.Belokopytova Dina f.Zhirnova Bao Yang Jingjing Liu Xiaomei Peng Eugene A.Vaganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological advances in quantitative wood anatomy have provided new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a novel approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylvestris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum values of cell radial diameter and cell wall thickness were recorded for each tree *** a low level of climatogenic stress, components of cell chronologies independent of cambial activity were separated to obtain significant climatic signals revealing the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitative wood anatomy Cell radial size Cell wall thickness Pinus sylvestris Climatic response

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氮碳包封fe_(3)C纳米颗粒作为高效富氧还原电催化剂

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Science China Materials 2024年第3期67卷 762-770页

作者：汪翠萍李智雷杰李松 Stijn f.L.Mertens 胡劲松 School of Chemical Engineering Anhui Province Key Laboratory of Specialty PolymersAnhui University of Science and TechnologyHuainan 232001China Department of Chemistry Energy Lancaster and Materials Science LancasterLancaster UniversityLancaster LA14YBUnited Kingdom Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

高活性MOf基催化剂的设计和合成为促进动力学不利的氧还原反应(ORR)过程开辟了新的途径.本研究通过在ZIf-8前驱体表面涂覆二茂铁甲酸,然后进行两步炭化工艺,设计和制备了一种具有新型结构的高效电催化剂,以提高ORR性能.两步炭化过程对... 详细信息

高活性MOf基催化剂的设计和合成为促进动力学不利的氧还原反应(ORR)过程开辟了新的途径.本研究通过在ZIf-8前驱体表面涂覆二茂铁甲酸,然后进行两步炭化工艺,设计和制备了一种具有新型结构的高效电催化剂,以提高ORR性能.两步炭化过程对于将热解fe_(3)C纳米颗粒封装到碳纳米管(CNTs)中以及将fe单原子隔离到N掺杂碳(NC)基体上至关重要.此外,fe元素的相对含量对优化催化剂的ORR性能至关重要.所制得fe_(3)C@CNTs/NC-M催化剂结构先进,在碱性溶液中表现出良好的长期稳定性和电催化ORR性能,其半波电位和极限电流分别达到0.941 V和6.31 mA cm^(-2).此外,该电催化剂在甲醇溶液中具有较强的耐受性和良好的稳定性.fe_(3)C@CNTs/NC-M锌空气电池(ZAB)具有1.525 V的开路电位,420 mA cm^(-2)时的峰值功率密度为348 mW cm^(-2),10 mA cm^(-2)时的最大容量为843 mA h g_(Zn)^(-1).因此,这种合成策略为构建具有有效和稳定的ORR性能的MOf基电催化材料提供了一条有效途径.

关键词： metal-organic frameworks carbon nanotubes N-doped carbon matrix oxygen reduction reaction Zn-air battery

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Melting of hydrous pyroxenites with alkali amphiboles in the continental mantle:*** element compositions of melts and minerals

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Geoscience frontiers 2024年第1期15卷 50-68页

作者： Stephen f.foley Isra S.Ezad School of Natural Sciences Macquarie UniversityNorth RydeNew South Wales 2109Australia Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

The trace element compositions of melts and minerals from high-pressure experiments on hydrous pyroxenites containing K-richterite are presented. The experiments used mixtures of a third each of the natural minerals clinopyroxene, phlogopite and K-richterite, some with the addition of 5% of an accessory phase ilmenite, rutile or apatite. Although the major element compositions of melts resemble natural lamproites, the trace element contents of most trace elements from the three-mineral mixture are much lower than in lamproites. Apatite is required in the source to provide high abundances of the rare earth elements, and either rutile and/or ilmenite is required to provide the high field strength elements Ti, Nb, Ta, Zr and Hf. Phlogopite controls the high levels of Rb, Cs and *** abundances of trace elements in the various starting mixtures vary strongly because of the use of natural minerals, we calculated mineral/melt partition coefficients (DMin/melt) using mineral modes and melting reactions and present trace element patterns for different degrees of partial melting of hydrous pyroxenites. Rb, Cs and Ba are compatible in phlogopite and the partition coefficient ratio phlogopite/K-richterite is high for Ba (136) and Rb (12). All melts have low contents of most of the first row transition elements, particularly Ni and Cu ((0.1-0.01)×primitive mantle). Nickel has high DMin/melt for all the major minerals (12 for K-richterite, 9.2 for phlogopite and 5.6 for Cpx) and so behaves at least as compatibly as in melting of peridotites. fluorine/chlorine ratios in melts are high and DMin/melt for fluorine decreases in the order apatite (2.2) > phlogopite (1.5) > K-richterite (0.87). The requirement for apatite and at least one Ti-oxide in the source of natural lamproites holds for mica pyroxenites that lack K-richterite. The results are used to model isotopic ageing in hydrous pyroxenite source rocks: phlogopite controls Sr isotopes, so that lamproites with relatively l

关键词： Hydrous pyroxenite Lamproite Trace elements Phlogopite K-richterite Apatite

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Artificial kidney: Challenges and opportunities

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World Journal of Transplantation 2024年第1期14卷 42-47页

作者： filippos f Karageorgos Stavros Neiros Konstantina-Eleni Karakasi Stella Vasileiadou Georgios Katsanos Nikolaos Antoniadis Georgios Tsoulfas Department of Transplantation Surgery Center for Research and Innovation in Solid Organ TransplantationAristotle University School of MedicineThessaloniki 54642Greece

This review aims to present the developments occurring in the field of artificial organs and particularly focuses on the presentation of developments in artificial *** challenges for biomedical engineering involved in overcoming the potential difficulties are showcased,as well as the importance of interdisciplinary collaboration in this marriage of medicine and *** this review,modern artificial kidneys and the research efforts trying to provide and promise artificial kidneys are *** what are the problems faced by each technology and to what extent is the effort enough to date?

关键词： Artificial kidney Implantable kidney Hemodialysis Peritoneal dialysis Endstage kidney disease

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Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

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Journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.Lobo Christopher D.Easton Mainak Majumder frank Witte Jörg f.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia Julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

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Durable and enhanced immunity against SARS-CoV-2 elicited by manganese nanoadjuvant formulated subunit vaccine

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Signal Transduction and Targeted Therapy 2024年第1期9卷 47-50页

作者： Mengyu Guo Mingjing Cao Jiufeng Sun Ziwei Chen Xin Wang Lianpan Dai George f.Gao Yuliang Zhao Yaling Wang Chunying Chen CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety&CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of ChinaBeijingChina Guangdong Provincial Institute of Public Health Guangdong Provincial Center for Disease Control and PreventionGuangzhouChina CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyBeijingChina

Dear editor,Vaccines are the most efficient and effective means to prevent infectious diseases,but improving the long-term protective efficacy is still a major challenge in contemporary vaccine development.1 The waning immunity varies depending on the diversification of the pathogen and the number of booster doses.1 Strategies to overcome this warrant is using adjuvants that amplify the immune response,and drive the production of memory B and T cells or long-lived plasma cells that recognize the pathogen for durable protection.2–4 Although existing adjuvants have achieved promising results,research on generating durable protective immunity is lacking in promoting vaccine development and staying ahead of global pandemics such as coronavirus disease 2019(COVID-19).The precisely designed nanoadjuvants can enhance lymph node targeting and increase antigenpresenting cell(APCs)uptake,achieving the co-delivery of adjuvants and antigens and activating innate and adaptive immune responses.5 Previously,we reported a manganese nanoadjuvant(MnARK)and receptor-binding domain(RBD)monomer antigen formulated nanovaccine.6 MnARK transported antigens to lymph nodes,activated the STING pathway,elicited strong neutralizing abilities and increased immune memory T cell percentage against the infection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).6 Regarding the long-term protection potential of MnARK for subunit vaccine development,we further explored the durable immune regulation abilities of MnARK to a SARS-CoV-2 RBD dimer antigen,which has been used in an approved COVID-19 subunit vaccine Zf2001 with aluminum adjuvant(alum).7,8 TEM result revealed that RBD dimer could interact with BSA on MnARK surface and epitope can be well preserved(Supplementary fig.1a).The size and zeta potential of MnARK-RBD dimer nanovaccine was~58 nm and-14 mV,respectively(Supplementary fig.1b,c).

关键词： manganese immunity protective

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一种评估非接触水下爆炸对海军复合船体影响的设计方法

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 316-326页

作者： f.Mannacio f.Di Marzo M.Gaiotti C.M.Rizzo M.Venturini Italian Navy Naval Support and Experimentation CentreCSSN Viale S.Bartolomeo40019126 La Spezia(Italy) University of Genova Polytechnic SchoolDITEN Via Montallegro116145 Genova(Italy).

Despite the non-contact underwater explosion phenomena(UNDEX)have been studied for decades and several numerical methods have been proposed in literature,its effects on military structures,especially composite ones,are even nowadays matter of *** early design phases,it is not always possible to verify the shock resistance of hull structures modelling the whole phenomenon,in which fluid,gas and solid properties must be properly set in a fully coupled fluid-structure interaction(fSI)numerical *** ones are extremely complex to set,computationally demanding and certainly not suitable for everyday design *** this paper,a simplified finite element(fE)model,easy to use in an early design phase,is ***,the structure and the fluid are *** this approximation,the fluid behaviour is simplified,using special finite elements,available in a commercial software *** choice reduces the computational time and numerical efforts avoiding the problem of combining computational fluid dynamics(CfD)and fE domains and equations in a fully coupled fluid-structure interaction model.A typical parallel body block of a minesweeper is modelled,using two-dimensional multi-layered shell elements to properly account for the composite materials *** the fluid instead,three dimensional volumetric elements,directly coupled to the structural elements,are *** addition,the same calculation is performed,modelling separately fluid in the CfD environment and structures in the finite element ***,realizing a fully coupled fluid-structure interaction *** results obtained by applying both numerical models are compared with the structural response measured on board of a composite ship during a full-scale shock *** simplified proposed procedure provides results in satisfactory agreement with experiments,allowing the validation of the *** are discussed and differences with the real phenomenon and fully coupled CfD+

关键词： Underwater explosions Shock resistance Composites fluid-structure interaction Experimental analysis Numerical simulation Vulnerability Preliminary design

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Stubborn Hypoxia in Neonates with D-Transposition of the Great Arteries after Arterial Switch Operation: Central Sleep Apnea as the Cause and Potential Indicator of Brain Immaturity

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Congenital Heart Disease 2024年第2期19卷 185-195页

作者： Camden L.Hebson Kyle Bliton Amr Y.Hammouda Kaitlyn Barr W.Hampton Gray Mohini Gunnett Waldemar f.Carlo Department of Pediatrics Division of Pediatric CardiologyUniversity of Alabama BirminghamBirmingham35233USA Department of Pediatrics Division of Pediatric PulmonologyUniversity of Alabama BirminghamBirmingham35233USA Department of Pediatrics University of Alabama BirminghamBirmingham35233USA Department of Surgery Division of Cardiothoracic SurgeryUniversity of Alabama BirminghamBirmingham35233USA

D-transposition of the great arteries(d-TGA)is surgically repaired with the arterial switch operation(ASO)with excellent results,however short and long-term morbidities still develop including neurocognitive *** significant central sleep apnea is uncommon in non-premature infants,but when present indicates immature autonomic control of respiration likely due to a neurologic *** report the unanticipatedfinding of central sleep apnea in four-term neonates with d-TGA after uncomplicated ASO,with the short-term complication of delayed hospital discharge and long-term concerns regarding this early marker of brain immaturity and its hindrance to normal *** this report,we will review each patient’s clinical course and then examine the literature on pediatric central sleep apnea,neurodevelopmental outcomes after ASO,and the important overlap of these entities in the care of patients going forward.

关键词： Transposition congenital heart disease sleep apnea polysomnography

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In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.f.Wang C.J.Wang W.V.Yue Z.J.Zhang Z.Q.Yue Department of Civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of Civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

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Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials Science 2024年第2期6卷 193-200页

作者： M.I.Ikim G.N.Gerasimov V.f.Gromov O.J.Ilegbusi L.I.Trakhtenberg N.N.Semenov federal Research Center for Chemical Physics of RAS MoscowRussia University of Central florida OrlandoFLUSA Moscow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)and InOOH are formed,which are the precursors of stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition from c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in composites based on c-In_(2)O_(3).Compared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2).

关键词： Cerium oxide Indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

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