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Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 324-336页

作者： HE Juan LI Yalin HOU Yunling ZHOU Aorigele WEI Yushuai chen xi DAI Jingen School of Civil Engineering and Architecture West Yunnan University of Applied SciencesDaliYunnan 671006China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100080China West Yunnan University of Applied Sciences DaliYunnan 671006China MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100080China

In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern xizang(Tibet).

关键词： rift Early Triassic magmatism Yarlung Zangbo Suture Zone Neo-Tethys Southern xizang Tibet

Service Function Chain Migration in LEO Satellite Networks

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China Communications 2024年第3期21卷 247-259页

作者： Geng Yuhui Wang Niwei chen xi Xu xiaofan Zhou Changsheng Yang Junyi xiao Zhenyu Cao xianbin School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Key Laboratory of Advanced Technology of Near Space Information System Ministry of Industry and Information Technology of ChinaBeijing 100191China Shanghai Key Laboratory of Satellite Network Shanghai 201204China Shanghai Satellite Network Research Institute Co. Ltd.Shanghai 201204China

With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite networks.While due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service failure.In this paper,we consider migration and establish an online migration model,especially considering the dynamic topology.Given the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as possible.Due to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are rejected.Simulation results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity.

关键词： network function virtualization(NFV) resource allocation satellite networks service function chain(SFC) SFC migration SFC placement soft-ware defined network(SDN)

Establishment of an Iron Deficiency Model by Iron Depletion in Pregnant Rats

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Biomedical and Environmental Sciences 2024年第2期37卷 210-215页

作者： chen xi HAN Chao ZHAO Jin Peng SHEN Shi WANG Li Yuan REN Shou WANG Tong Lei MA Yan XU Ze Chao HUO Jun Sheng Key Laboratory of Trace Element Nutrition National Health Commission of the People’s Republic of ChinaNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China

Anemia,a global public health problem,has significant adverse consequences on the cognitive development of children and the work capacity of adults;affecting social and economic development.Globally,roughly 43%of children under five years of age,38%of pregnant women,and 29%of nonpregnant women had anemia.Anemia during pregnancy significantly increases the risk of low birth weight and preterm birth.A 10 g/L increase in hemoglobin has been estimated to decrease the risk of maternal and perinatal mortality by 29%and 28%.

关键词： mortality pregnancy anemia

Ecological problems and ecological restoration zoning of the Aral Sea

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Journal of Arid Land 2024年第3期16卷 315-330页

作者： BAO Anming YU Tao XU Wenqiang LEI Jiaqiang JIAPAER Guli chen xi Tojibaev KOMILJON Shomurodov KHABIBULLO Xabibullaev B SAGIDULLAEVICH Idirisov KAMALATDIN State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Key Laboratory of GIS&RS Application Xinjiang Uygur Autonomous RegionUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China Institute of Botany of the Academy of Sciences of the Republic of Uzbekistan Tashkent 100125Uzbekistan International Innovation Center for Aral Sea Basin under the President of the Republic of Uzbekistan Nukus 230100Uzbekistan

The Aral Sea was the fourth largest lake in the world but it has shrunk dramatically as a result of irrational human activities, triggering the "Aral Sea ecological crisis". The ecological problems of the Aral Sea have attracted widespread attention, and the alleviation of the Aral Sea ecological crisis has reached a consensus among the five Central Asian countries(Kazakhstan, Uzbekistan, Tajikistan, Kyrgyzstan, and Turkmenistan). In the past decades, many ecological management measures have been implemented for the ecological restoration of the Aral Sea. However, due to the lack of regional planning and zoning, the results are not ideal. In this study, we mapped the ecological zoning of the Aral Sea from the perspective of ecological restoration based on soil type, soil salinity, surface water, groundwater table, Normalized Difference Vegetation Index(NDVI), land cover, and aerosol optical depth(AOD) data. Soil salinization and salt dust are the most prominent ecological problems in the Aral Sea. We divided the Aral Sea into 7 first-level ecological restoration subregions(North Aral Sea catchment area in the downstream of the Syr Darya River(Subregion Ⅰ);artificial flood overflow area in the downstream of the Aral Sea(Subregion Ⅱ);physical/chemical remediation area of the salt dust source area in the eastern part of the South Aral Sea(Subregion Ⅲ);physical/chemical remediation area of severe salinization in the central part of the South Aral Sea(Subregion Ⅳ);existing water surface and potential restoration area of the South Aral Sea(Subregion Ⅴ);Aral Sea vegetation natural recovery area(Subregion Ⅵ);and vegetation planting area with slight salinization in the South Aral Sea(Subregion Ⅶ)) and 14 second-level ecological restoration subregions according to the ecological zoning principles. Implementable measures are proposed for each ecological restoration subregion. For Subregion Ⅰ and Subregion Ⅱ with lower elevations, artificial flooding should be carried out to restore the surface of the Aral Sea. Subregion Ⅲ a

关键词： ecological restoration zoning salt and dust storms soil salinization ecological crisis Aral Sea Central Asia

A review of the neurotransmitter system associated with cognitive function of the cerebellum in Parkinson's disease

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Neural Regeneration Research 2024年第2期19卷 324-330页

作者： xi chen Yuhu Zhang Department of Neurology Guangdong Neuroscience InstituteGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Shantou University Medical College ShantouGuangdong ProvinceChina

The dichotomized brain system is a concept that was generalized from the‘dual syndrome hypothesis’to explain the heterogeneity of cognitive impairment,in which anterior and posterior brain systems are independent but partially overlap.The dopaminergic system acts on the anterior brain and is responsible for executive function,working memory,and planning.In contrast,the cholinergic system acts on the posterior brain and is responsible for semantic fluency and visuospatial function.Evidence from dopaminergic/cholinergic imaging or functional neuroimaging has shed significant insight relating to the involvement of the cerebellum in the cognitive process of patients with Parkinson’s disease.Previous research has reported evidence that the cerebellum receives both dopaminergic and cholinergic projections.However,whether these two neurotransmitter systems are associated with cognitive function has yet to be fully elucidated.Furthermore,the precise role of the cerebellum in patients with Parkinson’s disease and cognitive impairment remains unclear.Therefore,in this review,we summarize the cerebellar dopaminergic and cholinergic projections and their relationships with cognition,as reported by previous studies,and investigated the role of the cerebellum in patients with Parkinson’s disease and cognitive impairment,as determined by functional neuroimaging.Our findings will help us to understand the role of the cerebellum in the mechanisms underlying cognitive impairment in Parkinson’s disease.

关键词： anterior brain system cerebellum cholinergic cognitive impairment dopaminergic dual syndrome hypothesis neuroimage neurotransmitter Parkinson’s disease posterior brain system therapeutic targets

A Systematic Analysis of Early Life Exposure to the Chinese Famine(1959-1961)and the Health of Older Adults-China,2008-2023

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China CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： Chi Shen xi chen School of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant role.Consequently,it is crucial to comprehend the enduring effects of early life circumstances on health in old age.What is added by this report?In this study,we conducted a meta-analysis to examine the effects of the Chinese Famine(1959–1961)on the health of older adults.We also explored potential mechanisms underlying these effects.What are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Bio-screening and quantification of methyl paraben in vinegar and coconut juice separated by HPTLC

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Food Science and Human Wellness 2024年第3期13卷 1602-1607页

作者： Yisheng chen xingjun xi College of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China Insitute of Food Nutrition and Safety Shanxi Agricultural UniversityTaiyuan 030031China Institute of Agricultural Food Standardization China National Institute of StandardizationBeijing 100191China

As a widely used food preservative,methyl paraben was experimentally evidenced with serious hormonelike adverse effects.Herein,a high performance thin-layer chromatography platformed bioluminescent bioautography and image analysis for the selective quantification and confirmation of methyl paraben was proposed and validated in vinegar and coconut juice.First,the detectability of the bioautography to the analyte on different layer materials was estimated,revealing that normal silica gel was the best choice.After that,the liquid of sample extract and working solution were separated to overcome the background noises due to co-extracted matrices.The separation result was then coupled to the optimized bioautography,enabling instant and straightforward screening of the targeted conpound.For accurate quantification,bioluninescent inhibition pattern caused by the analyte was processed by image analysis,giving useful sensitivity(LOD>16 mg/kg),precision(RSD<10.1%)and accuracy(spike-recovery rate 76.9%-112.2%).Finally,the suspected result was confirmed by determining its MS fingerprint,further strengthening the reliability of screening.

关键词： High performance thin-layer chromatography Bio-screening Bioluminescence Image analysis Methyl paraben

B-cell lymphoma-2 phosphorylation at Ser70 site-related autophagy mediates puerarin-inhibited the apoptosis of MC3T3-E1 cells during osteoblastogenesis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 27-34页

作者： LI xi LIN xiangquan chen Dongdong LIU Hui the Third Clinical Medical College Fujian Medical University Department of Orthopedics Fuzhou Second HospitalFuzhou 350007China

OBJECTIVE:To explore the relationship between autophagy and apoptosis regulated by puerarin during osteoblastogenesis.METHODS:In this study,the effects of puerarin on the autophagic activity and apoptosis level of osteoblast precursors(MC3T3-E1 cells)was observed.Subsequently,the roles of puerarin on B-cell lymphoma-2(Bcl-2)phosphorylation at different sites in osteoblast precursors were observed.The effect of puerarin on the interaction between Bcl-2 and autophagy regulatory molecule or pro-apoptotic molecule was also investigated using Co-immunoprecipitation assays.In addition,the effect of puerarin on mitochondrial membrane potential of osteoblast precursors was also identified by mitochondrial membrane potential fluorescence probe assays.RESULTS:Our results showed that puerarin can promote the autophagic activity and apoptosis level of MC3T3-E1cells.In addition,puerarin promoted Bcl-2phosphorylation at Ser70 site,and the dissociation of Bcl-2-Beclin1 complex.Moreover,puerarin could enhance the binding of Bcl-2-Bcl-2-Associated X(Bax)complex in MC3T3-E1 cells.Furthermore,puerarin increased the mitochondrial membrane potential of MC3T3-E1 cells.CONCLUSIONS:Therefore,puerarin promotes Beclin1into autophagy flux through Bcl-2 phosphorylation at Ser70,thereby enhancing autophagy of osteoblast precursors,which mediates its anti-apoptotic role during osteoblastogenesis.Furthermore,the dissociation of Bcl-2-Beclin1 complex is conducive to the binding of Bcl-2-Bax complex,which resists the apoptosis of osteoblast precursors via the increased mitochondrial membrane potential.

关键词： puerarin osteoblasts autophagy apoptosis lymphoma B-cell

Characterization of Fe-containing particles in chengdu,southwest China,using single-particle aerosol mass spectrometry

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Journal of Environmental Sciences 2024年第2期136卷 110-120页

作者： Renjiang He Junke Zhang Luyao chen Wei Zhang Yingwei xi School of Public Health Southwest Medical UniversityLuzhou 646000China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Sichuan Environmental Monitoring Center Chengdu 610074China

Single-particle aerosol mass spectrometry was used to study the characteristics of Fecontaining particles during winter in chengdu,southwest China.The mass concentrations of PM_(2.5)and PM_(10)during the study period were 64±38 and 89±49μg/m~3,respectively,and NO_(2)and particulate matter were high compared with most other regions of China.The Fecontaining particles were divided into seven categories with different mass spectra,sources and aging characteristics.The highest contribution was from Fe mixed with carbonaceous components(Fe-C,23.1%)particles.Fe was more mixed with sulfate than nitrate and therefore the contribution of Fe mixed with sulfate(Fe-S,20.7%)particles was higher than that of Fe mixed with nitrate(Fe-N,12.5%)particles.The contributions from Fe-containing particles related to primary combustion were high in the small particle size range,whereas aged Fecontaining particles and dust-related particles were mostly found in the coarse particle size range.The air masses mainly originated from the west and east of chengdu,and the corresponding PM_(2.5)concentrations were 79±36 and 55±36μg/m~3,respectively.The west and east air masses showed stronger contributions of Fe-containing particles related to biomass burning(Fe-B)and fossil fuel combustion(Fe-C and Fe-S)particles,respectively.The southwest area contributed the most Fe-containing particles.Future assessments of the effects of Fe-containing particles during heavy pollution period should pay more attention to Fe-C and Fe-S particles.Emission-reduction of Fe-containing particles should consider both local emissions and short-distance transmission from the surrounding areas.

关键词： Fe-containing particles Particle composition Potential source areas Evolution chengdu