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Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition

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Acta Geochimica 2024年第4期43卷 661-676页

作者： Jie Wang Yun Liu research center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China CAS center for Excellence in comparative Planetology Hefei 230026China

Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion *** on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified ***,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the *** propose a new model designed for silicate melt evaporation under *** model considers multiple steps including mass transfer,chemical reaction,and *** derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,*** model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and ***,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and *** addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems.

关键词： Evaporation Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS

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Apolipoprotein E4 interferes with lipid metabolism to exacerbate depression-like behaviors in 5xFAD mice

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Animal Models and Experimental Medicine 2024年第3期7卷 347-361页

作者： Yanju Gong Mingfeng Li Min Liu Xinghan Wu Yanhong Li Chuan Qin Ling Zhang iNHC Key Laboratory of Human Disease comparative Medicine Beijing Engineering Research Center for Experimental Animal Models of Human Critical DiseasesInternational Center for Technology and lnnovation of Animal ModelComparative Medicine CenterInstitute of Laboratory Animal SciencesChinese Academy of Medical Sciences(CAMS)and Peking Union Medical College(PuMC)BeijingChina Changping National Laboratory(CPNL) BeijingChina

Background:Apolipoprotein E4(ApoE4)allele is the strongest genetic risk factor for late-onset Alzheimer's disease,and it can aggravate depressive symptoms in non-AD ***,the impact of ApoE4 on AD-associated depression-l ike behaviors and its underlying pathogenic mechanisms remain ***:This study developed a 5xFAD mouse model overexpressing human ApoE4(E4FAD).Behavioral assessments and synaptic function tests were conducted to explore the effects of ApoE4 on cognition and depression in 5xFAD *** in peripheral and central lipid metabolism,as well as the levels of serotonin(5-HT)andγ-aminobutyric acid(GABA)neurotransmitters in the prefrontal cortex,were *** addition,the protein levels of 24-dehydrocholesterol reductase/glycogen synthase kinase-3 beta/mammalian target of rapamycin(DHCR24/GSK3β/m TOR)and postsynaptic density protein 95/calmodulin-dependent protein kinase II/brain-derived neurotrophic factor(PSD95/CaMK-II/BDNF)were measured to investigate the molecular mechanism underlying the effects of ApoE4 on AD ***:Compared with 5xFAD mice,E4FAD mice exhibited more severe depressionlike behaviors and cognitive *** mice also exhibited increased amyloid-beta deposition in the hippocampus,increased astrocyte numbers,and decreased expression of depression-related neurotransmitters 5-HT and GABA in the prefrontal ***,lipid metabolism disorders were observed in E4FAD,manifesting as elevated low-density lipoprotein cholesterol and reduced high-density lipoprotein cholesterol in peripheral blood,decreased cholesterol level in the prefrontal cortex,and reduced expression of key enzymes and proteins related to cholesterol synthesis and *** expression of proteins related to the DHCR24/GSK3β/m TOR and PSD95/CaMK-II/BDNF pathways was also ***:This study found that ApoE4 overexpression exacerbates depressionlike behaviors in 5xFAD mice and confirmed that ApoE4 reduces co

关键词： 5xFAD mice Alzheimer's disease ApoE4 allele depression like

Generation of double knockout cattle via CRISPR-Cas9 ribonucleoprotein(RNP)electroporation

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Journal of Animal Science and Biotechnology 2024年第1期15卷 456-462页

作者： Gyeong-Min Gim Kyeong-Hyeon Eom Dong-Hyeok Kwon Dae-Jin Jung Dae-Hyun Kim Jun-Koo Yi Jae-Jung Ha Ji-Hyun Lee Seong-Beom Lee Woo-Jae Son Soo-Young Yum Won-Wu Lee Goo Jang Laboratory of Theriogenology and Biotechnology Department of Veterinary Clinical ScienceCollege of Veterinary Medicine and the Research Institute of Veterinary ScienceSeoul National UniversitySeoulRepublic of Korea LARTBio Co. Ltd.SeoulRepublic of Korea Gyeongsangbukdo Livestock research Institute YeongjuRepublic of Korea comparative Medicine Disease research center Seoul National UniversitySeoulRepublic of Korea

Background Genome editing has been considered as powerful tool in agricultural ***,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestational periods,single pregnancy,and high raising ***,technically demanding methods such as microinjection and somatic cell nuclear transfer(SCNT)are needed for gene editing in *** this point of view,electroporation in embryos has been risen as an *** First,editing efficiency of our electroporation methods were tested for *** of mutation on embryo was confirmed by T7E1 *** first combination,mutation rates for MSTN and PRNP were 57.6%±13.7%and 54.6%±13.5%,*** case of MSTN/BLG,mutation rates were 83.9%±23.6%for MSTN,84.5%±18.0%for ***,the double-KO embryos were transferred to surrogates and mutation rate was identified in resultant calves by targeted deep *** recipients were transferred for MSTN/PRNP,4 calves were delivered,and one calf underwent an induction for double *** surrogates were given double-KO embryos for MSTN/BLG,and four of the six calves that were born had mutations in both *** These data demonstrated that production of genome edited cattle via electroporation of RNP could be effectively ***,MSTN and PRNP from beef cattle and MSTN and BLG from dairy cattle have been born and they will be valuable resources for future precision breeding.

关键词： Beta-lactoglobulin Cattle CRISPR-Cas9 Electroporation Knockout MSTN PRNP

The lithology and composition of lunar mantle modifi ed by ilmenite bearing cumulate: A thermodynamic model

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Acta Geochimica 2024年第05期43卷 856-875页

作者： Wei Huang Wei Du State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences University of Chinese Academy of Sciences center for Excellence in comparative Planetology Chinese Academy of Sciences

Due to their high density,the ilmenite-bearing cumulates (IBC)(with or without KREEP) formed during the late-stage lunar magma ocean solidifi cation are thought to sink into the underlying lunar mantle and trigger lunar mantle *** evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary (CMB).However,partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant,thus preventing the IBC/KREEP layer from sinking to the ***,we perform thermodynamic simulation on the stability of lunar mantle cumulates at diff erent depths mixed with diff erent amounts of IBC/KREEP from an updated LMO *** modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt%partial melting in the shallow (～120 km) and a much larger degree of partial melting in the deep lunar mantle (～420 km).Due to the density contrast with the surrounding mantle,IBC/KREEP-bearing melts could potentially decouple under certain *** modifi ed lunar mantle by sinking of IBC/KREEP can better explain the formation of diff erent kinds of lunar basaltic magma than the primary lunar mantle formed through diff erentiation of lunar magma *** of IBC/KREEP back into the lunar mantle may introduce plagioclase,clinopyroxene,garnet,and incompatible radioactive elements into the deep lunar mantle,which will further aff ect the thermal and chemical evolution of the lunar interior.

关键词： Ilmenite-bearing cumulate KREEP Lunar mantle overturn Partial melting pMELTS

High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith

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Matter and Radiation at Extremes 2024年第2期9卷 90-97页

作者： Jing Yang Wei Du center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences(CAS)Guiyang 550081China CAS center for Excellence in comparative Planetology Hefei 230026China

Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution.

关键词： evolution minerals basalt

comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel research center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground Engineering research center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Ultrasound-driven self-decomposition porphyrins as metal-free CO precursors for gas and sonodynamic synergistic therapy

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Science China Chemistry 2024年第5期67卷 1624-1635页

作者： Shuxin Liu Jinjuan Ma Xiang Xu Aiguo Wang Nan Zheng School of Chemical Engineering Dalian University of TechnologyDalian 116024China Department of comparative Medicine Laboratory Animal center Dalian Medical UniversityDalian 116000China Cancer Hospital of Dalian University of Technology Shenyang 116000China

Carbon monoxide(CO) is an endogenous therapeutic gas with an anti-tumor effect. The precise delivery and controlled release of CO in tumor tissues play crucial roles in anti-cancer treatment. However, efficient in situ generation of CO from metal-free COreleasing molecules(CORMs) remains a formidable challenge. Herein, we develop ultrasound(US)-driven self-decomposition porphyrin as organic and metal-free US-CORMs, which can spatiotemporally control the CO release(347 mmol CO/mol porphyrin) efficiently under physiologically harmless US conditions(1.0 MHz, 1.5 W/cm^(2), 50% duty cycle, 50 min). Moreover,porphyrin as a sonosensitizer can also generate reactive oxygen species(ROS) under US treatment to achieve sonodynamic therapy(SDT). Advanced functions of such porphyrin-based CORMs in CO gas-sonodynamic synergistic treatment have been demonstrated by evaluating the in vitro and in vivo anti-tumor effects.

关键词： porphyrin sonodynamic therapy metal-free CO precursors ultrasound-driven gas therapy

Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region

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Advances in Atmospheric Sciences 2024年第5期41卷 801-816页

作者： Qiuyan DU Chun ZHAO Jiawang FENG Zining YANG Jiamin XU Jun GU Mingshuai ZHANG Mingyue XU Shengfu LIN Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS center for Excellence in comparative Planetology University of Science and Technology of ChinaHefei 230026China

Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality ***,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well *** this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are *** increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal *** general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary *** spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural *** summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation *** autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation.

关键词： PM_(2.5) forecasting uncertainties forecast lead time meteorological fields Beijing-Tianjin-Hebei region

Liberica coffee as an alternative cropping system for sustainable farming on Indonesian Peatlands

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 180-188页

作者： Bariot Hafif Yulius Ferry Budi Martono Rita Harni Kurnia Dewi Sasmita Busyra B.Saidi Maswar Maswar R.Bambang Heryanto Novizar Nazir Fahmuddin Agus Meynarti Sari Dewi Ibrahim National research and Innovation Agency Research Center for Estate CropsIndonesia National research and Innovation Agency Research Center for Food CropsIndonesia Faculty of Agricultural Technology Andalas UniversityIndonesia

Indonesian peatlands are a fragile ecosystem,and to protect it,growing Liberica coffee is a promising way for both the environment and the *** study aimed to evaluate the performance of the liberica coffee on peatland with different water tables and develop an improved cultivation system in this *** study area was in Tanjung Jabung Barat District,Jambi Province,*** plant age is greater than 15 years and the average plant density was about 1000 trees/*** study was conducted in two *** 1st stage was a survey to identify and characterize smallholder liberica coffee farming at three peatland zones,namely 0-100 m,200-300 m,and>400 m from the principal drainage canal,and the 2nd stage was a field experiment to test the effectiveness of amendments in improving liberica coffee growth and improving degraded *** treatments were arranged in a randomized complete block design with four replications,including manure(M),at the rate of 10 t/hm^(2);lime(L),3 t/hm^(2);peat surface elevation(P),and a farmer’s practice(Control)without manure and/or lime as a *** research revealed that liberica coffee can not tolerate high water table as it may stimulate disease incidence and cause low-quality ***,recycling of organic C of about 17.14 t/(hm^(2)·a)through cherry residue application and litter compensated part of the loss of organic C through CO_(2)emissions,coffee bean removal,and maintaining peat fertility for sustainable *** low yield of(0.70±0.12)t/(hm^(2)∙a)coffee bean could be increased to(0.87±0.24)and(0.94±0.14)t/(hm^(2)∙a)by adding 3 t/(hm^(2)∙3a)of lime or 10 t/(hm^(2)∙a)of manure,*** research revealed that water table management and amendments are two main factors in liberica coffee farming on *** is of great significance to study the cultivation technology of coffee in peatland.

关键词： degraded peat amendments water table cultivation system liberica coffee alternative cropping system sustainable farming Indonesian Peatlands