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Discovery of unusual phloroglucinol-triterpenoid adducts from Leptospermum scoparium and Xanthostemon chrysanthus by building blocks-based molecular networking

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Chinese Chemical Letters 2024年第6期35卷 353-357页

作者： jinyan Zhang Fen Liu Qian jin Xueyi Li Qiong Zhan Mu Chen Sisi Wang Zhenlong Wu Wencai ye Lei Wang State Key Laboratory of Bioactive Molecules and Druggability Assessment Jinan UniversityGuangzhou 510632China Center for Bioactive Natural Molecules and Innovative Drugs and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchJinan UniversityGuangzhou 510632China College of Pharmacy Jinan UniversityGuangzhou 510632China

The first phloroglucinol-triterpenoid hybrids,myrtphlotritins A-E(1-5),were rapidly recognized and isolated from two species of Myrtaceae by employing the building blocks-based molecular network(BBMN)*** 1-5 featured new carbon skeletons in which phloroglucinol derivatives were coupled with lupane-and dammarane-type triterpenoids through different linkage *** structures and absolute configurations were elucidated by comprehensive analysis of spectroscopic data and quantum chemical *** pathways for compounds 1-5 were proposed on the basis of the coexisting *** by the biogenetic pathways,the biomimetic synthesis of compound 1 was also ***,compounds 2,3,and 5 exhibited potent antiviral activities against herpes simplex virus type-1(HSV-1)infection,and compounds 2 and 5 displayed significant anti-inflammatory activities on RAW264.7 cells.

关键词： Phloroglucinol-triterpenoid adduct Myrtaceae Building blocks-based molecular network Biomimetic synthesis Antiviral activity Anti-inflammatory activity

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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts

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Materials Futures 2024年第1期3卷 165-180页

作者： Jonathan Ruiz Esquius Alec P LaGrow Haiyan jin Zhipeng yu Ana Araujo Rita Marques Adélio Mendes Lifeng Liu Clean Energy Cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal Carbon Science and Technology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China Laboratory for Process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

Proton exchange membrane(PEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M HClO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h without obvious *** in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic ***,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference *** IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for PEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly

风化过程中铼和硒的活动性及其对化石有机碳风化的指示

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中国科学：地球科学 2024年第3期54卷 760-770页

作者：张玉红汪进曲远馨朱超金章东中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049 西安地球环境创新研究院西安710061 西安交通大学全球环境变化研究院西安710049

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.... 详细信息

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.为了更好地认识这一指标的有效性,本文选择重庆市城口县下寒武统水井沱组页岩风化剖面为研究对象,通过元素含量、逐级提取实验等分析,探讨页岩风化序列中Re和硒(Se)的活动性及其与化石有机碳风化的关系.结果表明,化学蚀变指数(CIA)从基岩到风化层逐步升高,指示增强的风化强度.根据逐级提取实验和质量迁移系数(τ)的变化发现,页岩中的Re和Se主要赋存于有机质相,风化过程中与化石有机碳同步流失,而与页岩中的硫化物矿物氧化无明显相关;风化过程中Re和Se不同的地球化学行为导致其与化石有机碳非等量流失.本研究支持Re作为示踪化石有机碳风化的指标,而Se是示踪化石有机碳风化的潜在指标.未来需要不同类型沉积岩剖面与流域相结合的研究,明确河水Re和Se的来源及其与流域化石有机碳风化之间的关系.

关键词： Re和Se 页岩活动性化石有机碳化学风化

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First satellite observation of total column water vapor from the Chinese Environmental Trace Gases Monitoring Instrument

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Science China Earth Sciences 2024年

作者： Ran ZHAO Chengxin ZHANG Wenjing SU jin yE Ziwei LI Cheng LIU School of Environmental Science and Optoelectronic Technology University of Science and Technology of China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Department of Environmental Science and Engineering University of Science and Technology of China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of China

Atmospheric water vapor is a critical component of the Earth's water cycle and has significant impacts on weather,climate, and atmospheric chemistry. However, deficiencies remain in the coverage and accuracy of water vapor monitoring. In this study, we first retrieved the total column water vapor（TCWV） in the visible blue spectral band from two Chinese satellite UV-Vis spectrometers, the Environmental Trace Gases Monitoring Instruments（EMIs）, which are onboard the Chinese GaoFen-5（GF-5, since May 2018） and GaoFen-5B（GF-5B, since September 2021） satellites. Nevertheless, limited by factors such as the relatively lower spectral signal-to-noise ratio and weak absorption of water vapor, the accurate retrieval of TCWV from the EMI spectrum is rather challenging. Therefore, we improved the baseline TCWV retrieval based on the differential optical absorption technique, including the re-calibration of the on-orbit spectra, optimization of the spectral fitting, and bias correction in the fitted result. Sensitivity tests show that the mean retrieval TCWV error of the EMI decreased by 1.47 kg m–2compared to that using uncalibrated spectra. The improved spectral fitting significantly reduced the relative uncertainty of the water vapor slant column densities（SCD） by 13.42%, and increased the number of successful fits by 11.64%. The improved EMI TCWV retrieval results from both the GF-5 and GF-5B satellites show a trend consistent with the TROPOspheric Monitoring Instrument（TROPOMI）satellite observations, with a correlation coefficient（R） of 0.98 and a mean bias of 1.04 kg m–2（6.88%）. Ground-based validations showed that the correlation between the EMI TCWV retrievals from the GF-5B satellite（R=0.91） and sun photometer measurements was significantly higher than that from the GF-5 satellite（R=0.87）, which may have been due to the improved performance of the EMI instrument on the GF-5B satellite. Finally, we showed that an intense atmospheric river event could be successfully captu

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杂交水稻不同穗萌程度种子质量差异与穗萌分级研究

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作物学报 2024年第9期50卷 2310-2322页

作者：贾舒涵何璨陈敏刘家欣胡伟民胡晋关亚静浙江大学农业与生物技术学院现代种业研究所种子科学中心浙江杭州310058 中国共产党富民县委员会组织部云南昆明650400 浙江大学海南研究院海南三亚572025

研究不同穗萌程度种子质量,对科学划分穗萌级别,优化穗萌指标计算方法至关重要。本试验以钱优0508(Qianyou 0508, Qy0508)、y两优689 (y Liangyou 689, yLy689)两个籼型杂交水稻品种为材料,测定穗上不同穗萌程度种子的发芽指标,以及可... 详细信息

研究不同穗萌程度种子质量,对科学划分穗萌级别,优化穗萌指标计算方法至关重要。本试验以钱优0508(Qianyou 0508, Qy0508)、y两优689 (y Liangyou 689, yLy689)两个籼型杂交水稻品种为材料,测定穗上不同穗萌程度种子的发芽指标,以及可溶性糖、可溶性蛋白含量等生理指标,以此评估不同穗萌程度水稻种子的发芽质量。同时,采用自然晾干和38℃烘干2种方式干燥穗萌种子,并将种子在低温和水淹2种逆境条件下发芽,探究实际生产中不同干燥处理对已穗萌种子质量的影响,及不同穗萌程度种子萌发抗逆能力的差异。此外,由于水稻种子通常在蜡熟末期至完熟初期为最佳收获期,期间均可能遭遇不良气候条件导致种子穗萌,因此本研究对不同成熟时期的穗萌种子质量也进行了探讨。通过鉴定穗上不同萌动程度的种子质量,提出了新的水稻穗萌分级方法,即完整饱满未萌动种子为0级,胚根凸起但稃壳未开裂的种子为1级,胚根露出且可见长度不足2mm的种子为2级,胚根可见长度大于2 mm的种子为3级。与0级种子相比,1~3级穗萌种子的发芽率均显著下降,不正常幼苗率显著增加,在低温、水淹逆境下,该现象更明显。相对而言, 38℃烘干方式对种子质量的影响较自然晾干小,而授粉后35 d (35 DAP)成熟度高的种子发生穗萌后对种子质量影响较授粉后25 d (25 DAP)成熟度低的种子小。本研究经过对不同穗萌程度种子质量的研究,提出了新的穗萌分级方法,对准确评估田间水稻穗萌水平有重要价值。

关键词：水稻穗萌分级穗萌率种子质量

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C634y mutation in RET-induced multiple endocrine neoplasia type 2A:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2627-2635页

作者： Hui-Fen Zhang Shu-Ling Huang Wen-Li Wang yu-Qing Zhou Jun Jiang Zhuo-jin Dai Department of Endocrinology Dongguan Hospital of Guangzhou University of Chinese MedicineDongguan 523003Guangdong ProvinceChina Department of Science and Technology Services Beijing Macro and Micro Test Co.Ltd.Beijing 100318China The First Clinical Medical College Guangdong Medical UniversityZhanjiang 524023Guangdong ProvinceChina

BACKGROUND Multiple endocrine neoplasia type 2(MEN2)is a rare,autosomal dominant endocrine ***,the RET proto-oncogene is the only gene implicated in MEN2A *** an RET carrier is detected,family members should be screened to enable early detection of medullary thyroid carcinoma,pheochromocytoma,and *** these,medullary thyroid carcinoma is the main factor responsible for patient ***,delineating strategies to inform clinical follow-up and treatment plans based on genes is paramount for clinical *** SUMMARy Herein,we present RET proto-oncogene mutations,clinical characteristics,and treatment strategies in a family with MEN2A.A family study was conducted on patients diagnosed with *** was extracted from the peripheral blood of family members,and first-generation exon sequencing of the RET protooncogene was *** C634y mutation was identified in three family members spanning three *** patients were sequentially diagnosed with pheochromocytomas and bilateral medullary thyroid carcinomas.A 9-yearold child harboring the gene mutation was diagnosed with medullary thyroid *** resection of the tumors was *** family members were advised to undergo complete genetic testing related to the C634y mutation,and the corresponding treatments administered based on test results and associated clinical *** Advancements in MEN2A research are important for familial management,assessment of medullary thyroid cancer invasive risk,and deciding surgical timing.

关键词： Multiple endocrine neoplasia type 2A Mutation RET proto-oncogene Medullary thyroid carcinoma Pheochromocytoma Case report

Magnetic phase transition and continuous spin switching in a high-entropy orthoferrite single crystal

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Frontiers of physics 2024年第2期19卷 157-167页

作者： Wanting yang Shuang Zhu Xiong Luo Xiaoxuan Ma Chenfei Shi Huan Song Zhiqiang Sun yefei Guo yuriy Dedkov Baojuan Kang jin-Ke Bao Shixun Cao Department of Physics Shanghai UniversityShanghai 200444China Materials Genome Institute and International Center for Quantum and Molecular Structures Shanghai UniversityShanghai 200444China School of Physics Southeast UniversityNanjing 211189China Shanghai Key Laboratory of High Temperature Superconductors Shanghai UniversityShanghai 200444China

Rare-earth orthoferrite REFeO_(3)(where RE is a rare-earth ion)is gaining *** created a high-entropy orthoferrite(Tm_(0.2)Nd_(0.2)Dy_(0.2)y_(0.2)yb_(0.2))FeO_(3)(HEOR)by doping five RE ions in equimolar ratios and grew the single crystal by optical floating zone *** strongly tends to form a single-phase structure stabilized by high configurational *** the low-temperature region(11.6‒14.4 K),the spin reorientation transition(SRT)ofΓ_(2)(F_(x),C_(y),G_(z))‒Γ_(24)‒Γ_(4)(G_(x),A_(y),F_(z))*** weak ferromagnetic(FM)moment,which comes from the Fe sublattices distortion,rotates from the a-to *** two-step dynamic processes(Γ_(2)‒Γ_(24)‒Γ_(4))are identified by AC susceptibility *** in HEOR can be tuned in the range of 50‒60000 Oe,which is an order of magnitude larger than that of orthoferrites in the peer system,making it a candidate for high-field spin *** spin-switching(SSW)and continuous spin-switching(CSSW)effects occur under low magnetic fields due to the strong interactions between RE‒Fe *** CSSW effect is tunable between 20‒50 Oe,and hence,HEOR potentially can be applied to spin modulation ***,because of the strong anisotropy of magnetic entropy change()and refrigeration capacity(RC)based on its high configurational entropy,HEOR is expected to provide a novel approach for refrigeration by altering the orientations of the crystallographic axes(anisotropic configurational entropy).

关键词： high-entropy oxide rare-earth orthoferrite spin reorientation transition spin switching magnetocaloric effect

Matrix-Mediated Color-Tunable Ultralong Organic Room Temperature Phosphorescence of 7H-Benzo[c]carbazole Derivatives

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CCS Chemistry 2024年第3期6卷 798-811页

作者： Chen Qian Xue Zhang Zhimin Ma Xiaohua Fu Zewei Li Huiwen jin mingxing Chen Hong Jiang Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029 Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Building on the recent systematic research on 1Hbenzo[f]indole(Bd),an important advancement in constructing ultralong organic room temperature(UORTP)materials with a universal strategy via a readily obtained unit(7H-Benzo[c]carbazole,BCz)is proposed in this *** powders of BCz and its derivatives merely exhibit blue fluorescence at ambient ***,when BCz and its derivatives are dispersed into polymer or powder matrixes,strong photo-activated green UORTP can be observed from their doped systems at room ***,the UORTP color can be tuned between green and yellow depending on the *** ultralong phosphorescence originates from the generation of charge-separated states via *** matrixes play a key role in both stabilizing charge-separated states and controlling UORTP *** interestingly,when using polymethyl methacrylate as matrix,the doped films achieve stronger photo-activated ultralong phosphorescence underwater than in air at room *** Bd,BCz achieves better performance not only in ultralong phosphorescence properties but also in practical *** work gains a deeper insight into the mechanism of UORTP and paves a new approach to applying organic phosphorescent materials to underwater coating and imaging.

关键词： 7H-Benzo[c]carbazole ultralong organic room temperature phosphorescence ion radical matrix-mediated color tunning underwater application

Pre-operative visceral adipose tissue radiodensity is a potentially novel prognostic biomarker for early endoscopic post-operative recurrence in Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 740-750页

作者： Phillip Gu Shishir Dube Norman Gellada So yung Choi Susan Win yoo jin Lee Shaohong yang Talin Haritunians Gil y Melmed Eric A Vasiliauskas Niru Bonthala Gaurav Syal Andres J yarur David Ziring Shervin Rabizadeh Phillip Fleshner Cindy Kallman Suzanne Devkota Stephan R Targan Dalin Li Dermot PB McGovern Department of Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Imaging Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Biostatistics Shared Resource Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Internal Medicine Keimyung University School of MedicineDaegu 42601South Korea Department of Medicine University of California at Los AngelesLos AngelesCA 90095United States Department of Medicine University of California at San DiegoSan DiegoCA 92093United States Department of Pediatrics Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Surgery Cedars-Sinai Medical CenterLos AngelesCA 90048United States

BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic immune-mediated inflammatory disease(IMID)of the gastrointestinal tract that is increasing in incidence and prevalence globally[1].CD patients often undergo surgery for disease-related complic-ations and/or medically refractory ***,surgery is not curative,and many patients develop post-operative recurrence(POR)of CD with a significant proportion eventually requiring additional *** advances in early detection and therapeutics,the contemporary 10-year risk of surgery has improved from 50%to 26%,but the risk of recurrent surgery has remained unchanged at 30%,suggesting a need to improve post-operative management strategies[2].Presently,there are two accepted strategies to mitigate POR,but each have potential ***,patients start early post-operative pharmacologic prophylaxis within 4-6 wk after *** strategy can potentially overtreat a subset of patient who may not develop long-term disease recurrence off ***,these patients are at risk of medication-related adverse events and the direct and indirect costs associated with therapy with little or no benefit[3].The second strategy is performing early colonoscopy within 6-12 months after surgery and escalating therapy based on FOOTNOTES Author contributions:Gu P is the guarantor of the article and was involved in concept and design,data collection,statistical analysis,drafting of manuscript,and final approval of manuscript;Dube S and Choi Sy were involved in statistical analysis,drafting of the manuscript,and final approval of manuscript;Gellada N,Win S,Lee yJ and yang S were involved in the data collection,drafting of the manuscript,and final approval of manuscript;Haritunians T and Li D were involved in data analysis and interpretation,drafting

关键词： Crohn’s disease Surgery Visceral adipose tissue Mesenteric adipose tissue Creeping fat Computed tomography