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c, O, and Sr Isotope Geochemistry of the Vendian Shuram-Wonoka Anomaly and Associated Metasedimentary Rocks in the Inner Part of the Patom Upland (central Siberia)

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LITHOLOGY AND MINERAL RESOURcES 2021年第5期56卷 390-417页

作者： Pokrovsky, B. G. Bujakaite, M., I Kolesnikova, A. A. Petrov, O. L. Khlebnikov, M. S. Russian Acad Sci Geol Inst Moscow 119017 Russia

The Imnyakh Formation (1500-1800 m thick), which is developed east of the Mama-Bodaibo Synclinorium (inner zone of the Patom Upland), comprises crystalline limestones (marbles) and carbonate shales (metamorphic marls). The carbon and strontium isotope compositions (delta c-13(av) = -9.0 +/- 0.4 parts per thousand, Sr-87 /Sr-86 = 0.70810-0.70845) in these rocks are completely identical to those in unmetamorphosed limestones of the Zhuya Group (outer zone) and the Torgo Formation (adjacent part of the Siberian Platform), which are comparable with the global Ediacaran c isotope anomaly (Shuram-Wonoka event). Metamorphism was not accompanied by the removal of Sr whose content in marbles of the Imnyakh Formation are as high (up to 6290 mu g/g) as in limestones of the Zhuya Group in the deepest parts of the Patom paleobasin. Thus, metamorphism was only manifested in the depletion of rocks with the heavy oxygen isotope by 3-4 parts per thousand (delta O-18(av) = 17.2 +/- 1 parts per thousand), relative to unmetamorphosed limestones. carbonates of the pre-Imnyakh black carbonate-bearing shales and deep black crystalline limestones in the Khomolkha and Ugakhan formations are characterized by wide variations of delta c-13 (-4.0 to 7 parts per thousand) and delta O-18 (15.2 to 23.4 parts per thousand), indicating strong postsedimentary alterations. Nevertheless, their Early Vendian (Early Ediacaran) age is confirmed by such features as position in the section, abnormally high delta c-13 values, and the minimum value Sr-87 /Sr-86 = 0.70753 recorded in a sample with the Sr content of 11700 mu g/g. Although the isotope systems of carbonates in the Sogdiondon and Vitim formations (delta c-13 -14.2 to -3.7 parts per thousand, delta O-18 12.2 to 13.4 parts per thousand, and 8(87)Sr/Sr-86 0.71120 to 0.71337) occurring at the Neoproterozoic sequence base in the Zhuya River underwent even stronger modification, it is possible that delta c-13 values in these formations were initially ne

关键词： c O and Sr isotope geochemistry chemostratigraphy Vendian Ediacaran Shuram-Wonoka event central Siberia

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c/N ratios inform sustainable aerobic denitrification for nitrogen pollution control: Insights into the key parameter from a view of metabolic division

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JOURNAL OF cLEANER PRODUcTION 2023年第1期414卷

作者： Zhang, Meng Lu, Huifeng cai, Lei Sun, Pan Ma, Bin Li, Junchi chen, Guangsuo Ruan, Yunjie Zhejiang Univ Inst Agr Bioenvironm Engn Coll Biosyst Engn & Food Sci Hangzhou 310058 Peoples R China Zhejiang Univ Coll Environm & Resource Sci Dept Environm Engn Hangzhou 310058 Peoples R China Zhejiang Univ Rural Dev Acad Hangzhou 310058 Peoples R China Zhejiang Prov Key Lab Water Pollut Control & Envir Hangzhou Peoples R China Zhejiang Gongshang Univ Coll Food Sci & Biotechnol Lab Microbial Resources Hangzhou 310035 Peoples R China Zhejiang Univ Inst Soil & Water Resources & Environm Sci Coll Environm & Resource Sci Hangzhou 310058 Peoples R China

Aerobic denitrification is a feasible and sustainable process for nitrogen removal in environmental protection. The c/N ratio was the vital one that has a significant impact on the performance. However, comprehension of the c/N ratio effect on this bioprocess was not well clarified. In this study, the response of an aerobic denitrifier (Pseudomonas balearica strain RAD-17) to the c/N ratio was investigated from a view of metabolism. It was found that a high total nitrogen (TN) removal efficiency of about 95% was achieved with the dosing c/N ratio of 7.5, while only a slight increase when the dosing c/N ratios were further increased to a high range of 10-30. The carbon validity was out of sync with TN removal and a balance between the two was realizable at a dosing c/N ratio of 7.5 based on the economic consideration. Moreover, weakened assimilation while enhanced respiration along with the increased c/N ratios was revealed, evidenced by the decreased net intracellular nitrogen and increased nitrogenous gas proportions in nitrogen balance analysis. The growth characteristics in terms of cell number and OD600 showed a division for the high flux of nitrate and organics directed to assimilation and respiration, respectively. The expression levels of carbon and nitrate metabolism-related function genes in P. balearica supported the results above. The c/N ratio of 5.0-7.5 was supposed to be the turning region for the metabolism division between assimilation and respiration in aerobic denitrifying. The results are expected to offer a guideline for the decision made for organics supply for the aerobic denitrification process and support its sustainable application.

关键词： Aerobic denitrification c N ratio Nitrogen balance Growth characteristics Functional genes Metabolic division

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RPO-14c技术及其在有机地球化学研究上的应用

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海洋地质与第四纪地质 2024年

作者：马海悦包锐中国海洋大学海洋化学理论与工程技术教育部重点实验室

基于沉积物样品的热稳定性进行分析和表征是稳定有机碳性质研究的常用方法，反映和重建了有机碳在环境中的演化和循环过程。热裂解/氧化（Ramped Pyrolysis/Oxidation，RPO）-14c分析技术及其应用是目前有机地球化学研究的前沿领域，也... 详细信息

基于沉积物样品的热稳定性进行分析和表征是稳定有机碳性质研究的常用方法，反映和重建了有机碳在环境中的演化和循环过程。热裂解/氧化（Ramped Pyrolysis/Oxidation，RPO）-14c分析技术及其应用是目前有机地球化学研究的前沿领域，也是研究沉积物有机碳埋藏与保存过程的有效方法。本文初步介绍了RPO-14c分析的测试方法和基本原理，阐述了热裂解/氧化及14c分析的装置细节，指出了包括装置改造、温度控制等在内的技术改进及与不同方法的联用拓展。RPO-14c分析技术在有机地球化学领域的沉积物研究方面得到了较广泛的应用：①揭示有机碳迁移、改造和保存机制；②改进沉积物年代学；③示踪沉积物记录的环境污染。RPO-14c能够对不同热稳定性有机碳进行高效分离，因此沉积物有机碳在自然环境中产生、迁移、改造、埋藏的过程能够借助热解特征得以重建，进而反演和评估全球范围内的有机碳循环机制和碳汇格局。最后，总结了该技术在海洋有机碳表征方面的应用前景及未来发展方向，对未来在更广泛的研究区域开展相关研究具有启示意义。

关键词：热裂解/氧化沉积物有机碳 c 碳循环

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c. elegans: Sensing the low-frequency profile of amplitude-modulated ultrasound

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ULTRASONIcS 2023年 128卷 106887页

作者： Long, Tianyang Xie, Linzhou Pulati, Mayibaier Wen, Quan Guo, Xiasheng Zhang, Dong Nanjing Univ Sch Phys Collaborat Innovat Ctr Adv Microstruct Key Lab Modern Acoust MOE Nanjing 210093 Peoples R China Univ Sci & Technol China Sch Life Sci Hefei Natl Lab Phys Sci Microscale Hefei 230027 Peoples R China

Several research groups have demonstrated that c. elegans can respond to pulsed ultrasound stimuli, and elucidating the underlying mechanisms is necessary to develop ultrasound neuromodulation. Here, amplitude -modulated (AM) ultrasound is applied to c. elegans, and its behavioral responses are investigated in detail. By loading surface acoustic waves (SAWs) onto free-moving worms on an agar surface, a carrier wave with a fre-quency of 8.80 MHz is selected. The signal is modulated by a rectangular or sinusoidal profile. It is demonstrated that sinusoidal modulation can produce similar responses in worms to rectangular modulation, with the strongest responses occurring at modulation frequencies of around 1.00 kHz. Meanwhile, the behavioral response is relatively weak when the ultrasonic signal is unmodulated, that is, when only the carrier wave is applied. At modulation frequencies other than 100.00 Hz to 10.00 kHz, the worms respond weakly, but when a second modulation frequency of 1.00 kHz is introduced, an improvement in response can be observed. These results suggest that c. elegans may sense the low-frequency envelope and respond to amplitude-modulated ultrasonic stimuli like an amplitude demodulator. MEc-4, an ion channel for touch sensing, is involved in the behavioral response of c. elegans to ultrasound in the present setup.

关键词： Ultrasonic neuromodulation Amplitude demodulation c elegans Behavioral response

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cynanchum quangbinhense (Apocynaceae: Asclepiadoideae), a new species from Vietnam, and additional information on c. officinale

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TAIWANIA 2021年第4期66卷 459-465页

作者： Van The Pham Thanh Trang Pham Ngoc Bon Trinh Sinh Khang Nguyen Minh Truong Dao Nuraliev, Maxim S. Van Lang Univ Sci & Technol Adv Inst Lab Ecol & Environm Management Ho Chi Minh City Vietnam Van Lang Univ Fac Technol Ho Chi Minh City Vietnam Vietnam Natl Univ Forestry Fac Forest Resource & Environm Management Dept Forest Plant Hanoi Vietnam Vietnamese Acad Forest Sci Silviculture Res Inst Dept Silviculture Fdn & Forest Phytodivers Hanoi Vietnam Vietnam Acad Sci & Technol Inst Ecol & Biol Resources 18 Hoang Quoc Viet Rd Hanoi Vietnam Vietnam Natl Univ Cent Inst Nat Resources & Environm Studies Hanoi Vietnam Moscow MV Lomonosov State Univ Biol Fac Dept Higher Plants 112Leninskie Gory Moscow 119234 Russia Joint Russian Vietnamese Trop Sci & Technol Ctr Hanoi Vietnam

This research provides a description and illustrations for a new species from the Phong Nha-Ke Bang National Park, cynanchum quangbinhense. The distribution, habitat, phenology and conservation assessment for the species are also presented. The new species differs from closely related species, c. ovalifolium in many characters such as leaf shape, inflorescence type, fewer and smaller flowers, colour of petals, margins of the corona, and anthers appendages shape, and differs from c. kwangsiense in having small leaves, umbellate inflorescences, triangular sepals, retuse apex of petals, and plicate margin of corona. Our discovery raises the known species of this genus in Vietnam to seven. In addition, a key to species of cynanchum in Vietnam, and notes on morphological variation of c. officinale are presented in this paper.

关键词： cynanchum kwangsiense c ovalifolium conservation Indochina IUcN National Park taxonomic key

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BIOMEDIcAL c/EBP 13 Mediates the Aberrant Inflammatory Response and cell cycle Arrest in Lps-stimulated Human Renal Tubular Epithelial cells by Regulating NF- KB Pathway

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ARcHIVES OF MEDIcAL RESEARcH 2021年第6期52卷 603-610页

作者： Yang, Ni Wang, Hai Zhang, Rui Niu, Zequn Zheng, Shaowei Zhang, Zhengliang Xi An Jiao Tong Univ Xibei Hosp Emergency Dept Affiliated Hosp 2 Xiwu Rd 157 Xian Peoples R China

Background and Aims. The main cause of sepsis-induced Acute kidney injury (AKI) is acute infection after surgery and subsequent progression. However, the mechanism by which AKI is caused and developed from sepsis are not completely known. Herein, we determined the role of ccAAT/enhancer-binding protein 13 (c/EBP 13) in sepsis-induced AKI Methods. c/EBP 13 expression was up or down-regulated in LPS-stimulated human renal tubular epithelial cells in vitro by recombinant adenoviruses or siRNA. Subsequent analyses included the test of TNF- a and IL-6 levels by ELISA, cell cycle assay by flow cytometry. Results. c/EBP 13 was aberrantly expressed in renal tubular epithelial HK-2 cells exposed to LPS. c/EBP beta overexpression significantly enhanced, but c/EBP 13 silencing obviously decreased the production and secretion of inflammatory cytokines TNF- a and IL-6 induced by LPS stimulus in HK-2 cells. And the cell cycle arrest of HK-2 cells induced by LPS was also enhanced after c/EBP beta overexpression while attenuated after c/EBP 13 silencing. consistent pattern of changes in cyclin D1 and p21 expression were observed in LPS-stimulated HK-2 cells after c/EBP 13 silencing and c/EBP 13 overexpression. Additionally, the increased p-NF- KB levels induced by LPS were found to be obviously decreased after c/EBP 13 silencing in HK-2 cells. And the enhanced TNF- a and IL-6 secretion as well as cell cycle arrest by c/EBP beta overexpression were blocked by BAY11-7082 inhibitor of NF- KB pathway. conclusions. c/EBP 13 could mediate the LPS-induced aberrant inflammatory response and cell cycle arrest in tubular epithelial cells by NF- KB pathway. (c) 2021 Instituto Mexicano del Seguro Social (IMSS). Published by Elsevier Inc. All rights reserved.

关键词： Sepsis AKI c EBP 13 Inflammatory response cell cycle arrest NF-KB

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Hydrolysis of B₂pin₂ over Pd/c catalyst: High Efficiency, Mechanism, and in situ Tandem Reaction

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EUROPEAN JOURNAL OF INORGANIc cHEMISTRY 2021年第27期2021卷 2797-2800页

作者： Li, Ning Shen, Jialu Liu, Xiang China Three Gorges Univ Coll Mat & Chem Engn Key Lab Inorgan Nonmetall Crystalline & Energy Co Anal & Testing Ctr Yichang 443002 Hubei Peoples R China

A facile and effective synthesis of H-2 or D-2 from Pd/c catalyzed hydrolysis of B(2)pin(2) has first been developed. Among them, B(2)pin(2) is frequently used for borylation reaction, and has rarely been used for hydrogen evolution. The kinetic isotope effects (KIEs) and tandem reaction for diphenylacetylene and norbornene hydrogenation have confirmed both two H atoms of H-2 gas are provided from H2O. This is contrary to other boron compounds hydrolysis (including NH3BH3, NaBH4), which generates H-2 with only one H atom provided by water and the other one by boron compounds. Note that the hydrolysis of B(2)pin(2) in D2O also provides an easy and useful synthesis of D-2.

关键词： B(2)pin(2) Pd c Hydrolysis KIE Tandem reaction

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corrosion behaviors of multilayer c/cr/SS bipolar plates for proton exchange membrane fuel cells under dynamic potential polarization based on New European Driving cycle

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cORROSION ScIENcE 2023年第1期214卷

作者： Hu, Qian Gao, Jia-Yi Shu, Shi Xu, Yu-Xuan Luo, Jing-Li Wang, Xian-Zong Northwestern Polytech Univ Shenzhen Res & Dev Inst Shenzhen 518057 Peoples R China Northwestern Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China Univ Alberta Dept Chem & Mat Engn Edmonton AB T6G 1H9 Canada Shenzhen Univ Coll Mat Sci & Engn Shenzhen 518060 Peoples R China

The New European Driving cycle (NEDc) induces remarkable degradation of proton exchange membrane fuel cells. The long-term cyclic dynamic potential polarizations based on NEDc with four different Epeak are inves-tigated on the multilayer c/cr coated SS316L (c/cr/SS) bipolar plates. c/cr/SS achieves superior small IcRs and low corrosion rate with Epeak up to 1.12 V, demonstrating great potential for commercial applications. However, mild local corrosion occurs at 1.16 V and accelerates at 1.22 V, resulted by the dissolution initiated at the heterogeneous interface. The present work offers new insights into NEDc-based potential polarization induced degradation on c/cr/SS.

关键词： New European Driving cycle c cr coating corrosion Metal bipolar plates Proton exchange membrane fuel cells

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Effect of microstructure evaluation during the PIP process on macroscopic properties of c/c composites

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cOMPOSITE STRUcTURES 2023年第1期308卷

作者： Yu, Mingming Li, Hongli Xue, Kun Xie, Wang Zhang, Liying Ren, Musu Fang, Lin Shanghai Univ Res Ctr Composite Mat Engn Res Ctr Mat Composit & Adv Dispers Technol Minist Educ 99 Shangda Rd Shanghai 200444 Peoples R China Donghua Univ Shanghai Collaborat Innovat Ctr High Performance F Ctr Civil Aviat Composites State Key Lab Modificat Chem Fibers & Polymer Mat 2999 Renmin North Rd Shanghai 201620 Peoples R China

carbon/carbon (c/c) composites have become one of the key new materials in the 21st century due to their excellent properties, including excellent temperature resistance, high electrical conductivity and high mechan-ical strength. This work analyzed the effects of microstructure evaluation of c/c composite materials at different stages of the precursor impregnation and pyrolysis (PIP) process on the compression and electromagnetic interference (EMI) shielding properties of c/c composites. It was found that the pores in the diameter range of 4-30 mu m were the main components of the internal pores of the material during the PIP process. The compressive strength of the c/c composites increased with increasing densification period, and the intrabundle pores had a significant effect on the compressive properties. The electrical conductivity and EMI shielding efficiency of the c/ c composites increased with increasing degree of densification, and the main reason for shielding electromag-netic waves was the reflection of the incident power.

关键词： c c composites Pore evolution compression properties Electromagnetic shielding properties

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Gaining an understanding of behavioral genetics through studies of foraging in Drosophila and learning in c. elegans

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JOURNAL OF NEUROGENETIcS 2021年第3期35卷 119-131页

作者： Reiss, Aaron P. Rankin, catharine H. Univ British Columbia Dept Psychol 2136 West Mall Vancouver BC V6T 1Z4 Canada Univ British Columbia Djavad Mowafaghian Ctr Brain Hlth Vancouver BC Canada

The pursuit of understanding behavior has led to investigations of how genes, the environment, and the nervous system all work together to produce and influence behavior, giving rise to a field of research known as behavioral neurogenetics. This review focuses on the research journeys of two pioneers of aspects of behavioral neurogenetic research: Dr. Marla Sokolowski and Dr. catharine Rankin as examples of how different approaches have been used to understand relationships between genes and behavior. Marla Sokolowski's research is centered around the discovery and analysis of foraging, a gene responsible for the natural behavioral polymorphism of Drosophila melanogaster larvae foraging behavior. catharine Rankin's work began with demonstrating the ability to learn in caenorhabditis elegans and then setting out to investigate the mechanisms underlying the "simplest" form of learning, habituation. Using these simple invertebrate organisms both investigators were able to perform in-depth dissections of behavior at genetic and molecular levels. By exploring their research and highlighting their findings we present ways their work has furthered our understanding of behavior and contributed to the field of behavioral neurogenetics.

关键词： Drosophila foraging c elegans learning behavioral neurogenetics

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