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Structural elucidation of the Polymeric Condensed Tannins of Acacia nilotica Subspecies by ^(13)C NMR, MALDI-TOF and TMA as Sources of Bioadhesives

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Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab Osman Antonio Pizzi bertrand Charrier Institute of engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan eNSTIB-LeRMAB University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOe)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ***(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOe at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13C NMR MALDI-ToF

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评估地震场地响应中土体的非线性行为:KiK-net台网强震数据的统计分析

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世界地震译丛 2014年第5期45卷 53-77页

作者： J.Régnier H.Cadet L.F.Bonilla e.bertrand J.-F.Semblat 杨国栋郑和祥甘肃省地震局

通过日本KiK-net台网数据库的各种地震记录,研究了土体的非线性行为对场地响应的影响。这个台网由不少于688个地表—井下仪器构成,从这个台网还获得了直到井孔深度的剪切波和压缩波速度剖面的特征。为了通过计算每个场地的地表与井下频... 详细信息

通过日本KiK-net台网数据库的各种地震记录,研究了土体的非线性行为对场地响应的影响。这个台网由不少于688个地表—井下仪器构成,从这个台网还获得了直到井孔深度的剪切波和压缩波速度剖面的特征。为了通过计算每个场地的地表与井下频谱比来表征土体的线性行为,我们挑选了井下台站地震动峰值加速度(PGA)50cm/s2)计算的场地响应曲线相对线性表征的变化被认为是由非线性土体行为造成的。为了描述每个事件土体非线性行为对场地响应的影响,我们提出了场地响应曲线相对线性估计的变化(放大或衰减)百分比(PNL ev,非线性百分比)和有关的位移频率(Sh ev)。这些参数被用于估计非线性场地响应显著区别于相应线性场地响应的概率。我们发现,不管何种场地,这个概率即使对低输入地震动峰值加速度(井下传感器的值不小于30cm/s2)也是重要的。这表明,在中强地震动场地响应评估中必须考虑非线性土体行为。此外,对记录了至少两个强震事件(井下PGA>50cm/s2)的KiK-net台网数据库的54个场地,我们定义了每个场地的表征土体非线性行为对场地响应影响的另外4个参数:(1)地震动峰值加速度阈值(PGA th),定义为PNL ev高于10%的地震动峰值加速度值;(2)地震动峰值加速度为50cm/s2的特定场地的PNL(PNL site);(3)地震动峰值加速度为50cm/s2的卓越频率的特定场地移位(Sh site);(4)在非线性和线性场地响应之间观测到衰减的频率(fNL)。我们观察到在fNL之下的频率,非线性土体行为可增强放大作用。我们发现fNL介于场地响应基频率和卓越共振频率之间,近地表具有V S反差的场地触发低地震动峰值加速度输入阈值的非线性行为。这些结果表明,非线性行为多发生在地表土层中。此外,通过研究地表的地震水平与垂直频谱比的土体非线性行为,我们发现它们对评估fNL频率和位移频率(Sh site)能够给出满意的结果(等价于井下场地响应的分析),这表明本研究获得的部分结果可以扩展到没有井下传感器的其他数据库。

关键词：非线性行为场地响应地震记录强震数据土体地震动峰值加速度台网统计分析

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A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications

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Journal of Renewable Materials 2024年第4期12卷 721-736页

作者： Wadah Mohammed Zeinab Osman Salah elarabi bertrand Charrier Institute of Analytical Sciences and Physical-Chemistry for the environment and Materials-Xylomat University of Pau and the Adour RegionE2S UPPACNRSIPREM-UMR 5254Mont de Marsan40004France Institute of engineering Research and Materials Technology(IeRMT) National Center for Research(NCR)Ministry of Higher Education and Scientific ResearchKhartoum11111Sudan Faculty of Industries engineering and Technology University of GeziraGezira State21111Sudan

The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and *** thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the *** this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy *** chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)*** total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the *** evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were *** chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%*** FTIR curves demonstrated a notable similarity among the *** TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton *** DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast *** higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,*** three fibers have a high potential for biocomposites and bioenergy material manufacturing.

关键词： Bagasse kenaf bast fibers cotton stalks TGA DSC FTIR

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From the unknown to spotlight:newly identified hormone adjusts hepatic cholesterol synthesis to dietary uptake

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2845-2847页

作者： Yakum bertrand Nkeh Resul Gökberk elgin Gesine Saher Project Group Biology of Lipids Department of NeurogeneticsMax Planck Institute for Multidisciplinary SciencesGöttingenGermany

In a study published in Cell,Hu and colleagues discovered that the signaling activity of the intestinal hormone Cholesin leads to the attenuation of hepatic cholesterol synthesis in response to intestinal absorption thereby maintaining homeostatic levels of circulating cholesterol.1 These findings have major translational implications as they provide a potential new target for the management of hypercholesterolemia and associated disorders.

关键词： cholesterol hepatic synthesis

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Deciphered: Whole-Process People's Democracy

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Beijing Review 2024年第43期67卷 18-19页

作者： Arnaud bertrand 不详

In the West,skepticism often arises when China describes its political system as-a democracy,specifically a"wholeprocess people's democracy."However,this skepticism is frequently rooted in a lack of understanding about what China means by the term,how it differs from liberal democracy,and why the Chinese Government considers it an effective system for the country.

关键词： system arise Whole

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Recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

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earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao RuiLong Guo Yong Wei bertrand Bonfond Denis Grodent BinZheng Zhang William R.Dunn ZuYin Pu Key Laboratory of earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial environment Institute of Space SciencesShandong University Department of earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. Recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(Guo RL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; Guo RL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

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A high-power electromagnetic source for disabling improvised explosive devices

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High Voltage 2024年第2期9卷 403-409页

作者： Laurent Ariztia Njomza Ibrahimi Alexey Zhabin Antoine Silvestre de Ferron Marc Rivaletto edson Martinod Valérie.bertrand Bucur Novac Laurent Pécastaing Universite de Pau et des Pays de l’Adour E2S UPPASIAMEPauFrance XLIM UMR CNRS BriveLimogesFrance CISTeMe LimogesFrance Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK

Ultra-wideband(UWB)microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter-terrorism *** authors present the main findings of a research dedicated to the development of a pulsed power-driven electromagnetic field source for disabling improvised explosive devices(IeD).The pulsed power generator driving the source is a 13-stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV,with a pulse repetition frequency(PRF)of up to 100 *** generator is coupled to a bipolar pulse forming line,providing bipolar pulses with a dV/dt of around 1.6 MV/*** pulsed power system feeds an array composed of 16 Koshelev-type UWB antennas through an impedance matching *** resulting electromagnetic source is capable to produce pulsed electric fields(PeFs)having a figure-of-merit(FOM)of 1 ***,practical experiments were carried out to study the effects of the PeFs on *** targets used in the present study are M2B type flashbulbs,known to have the same susceptibility as the US army M6 *** configurations of wires(shielded,twisted,etc)with different lengths were used in connecting items inside these *** tests were performed by placing the flashbulbs at different distances to determine the essential parameters(i.e.,amplitude,duration,and frequency range)of the PeFs required to trigger *** overview of the experimental campaign and the main findings are also presented followed by conclusions.

关键词： power bipolar source

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Fe-Ti Oxide Mineralization in the XV Intrusion,Bafq Mining District,Central Iran:Insights from Mineralogy,Mineral Chemistry and S Isotopic Data

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Journal of earth Science 2024年第5期35卷 1704-1719页

作者： Sakine Amraei Majid Ghasemi Siani Mohammad Yazdi Liang Qiu bertrand Moine Minghua Ren Department of Inorganic Geology and Water Faculty of Earth SciencesShahid Beheshti UniversityTehran Q9XV+XG7Iran Department of Geochemistry Faculty of Earth SciencesKharazmi UniversityTehran PC3G+QPJIran State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China Université Clermont Auvergne CNRSIRDOPGCLaboratoire Magmas et VolcansAubiere F-63178France Department of Geoscience University of NevadaLas Vegas NV 89154USA

The mafic-ultramafic intrusion in the XV anomaly area,contains magmatic Fe-Ti oxides±(p)ore,is located in the Bafq mining district in the Central *** consists of cumulate and layered Fe-Ti-bearing gabbros and *** mineral assemblages include clinopyroxene,Fe-Ti oxides,plagioclase,amphibole,apatite and sulfides(pyrite and chalcopyrite).The Fe-Ti oxides mainly consist of magnetite-titanomagnetite and ilmenite,which occurred as disseminated,intergrowth,lamellae(trellis and sandwich textures)and *** in the gabbroic rocks is from the near end-member of Fe_(3)O_(4)(etite containing up to 8 wt.%TiO_(2)(about3.73 wt.%to 26.84 wt.%Ulvospinel(X_(Usp))).Magnetite in pyroxenite rocks is characterized with TiO_(2)range from 0.46 wt.%to 3.14 wt.%(X_(Usp)varied from 1.76 wt.%to 10.46 wt.%).The abundances of V_(2)O_(3)range from 0.03 wt.%to 1.29 wt.%and 0.24 wt.%to 1.00 wt.%for gabbro and pyroxenite,respectively.X_(Usp)contents of magnetite show insignificant correlations with Al_(2)O_(3)and *** average XIlmin the ilmenite of gabbro is 92%,whereas it is 90.37%in the pyroxenite *** MgO and V_(2)O_(3)contents show a slightly positive correlation with TiO_(2)in *** composition of clinopyroxenes in gabbro and pyroxenite rocks fall in the diopside to augite field with Mg#ranging from 67 to 98 and 74 to 96,*** both rock types,amphiboles are mainly pargasite and rarely *** in pyroxenite rocks is clustered in the labradorite to andesine fields with a compositional ranges of An46-69and in gabboic rocks fall in two fields with compositional ranges of albite with An0.65-5.95and labradorite with ***δ34S isotopic values cover a limited range from+3.15‰to+4.10‰V-CDT consistent with magmatic ***-Ti mineralization is formed in two stages,minor inclusions of Fe-Ti oxide minerals in the pyroxene and plagioclase crystallized in the early magmatic stage,whereas interstitial oxide

关键词： mafic-ultramafic intrusion Fe-Ti oxides gravitational settling mineral chemistry Bafq mining district Central Iran mineral deposits

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Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

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Journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： Jérémy Raffin Yves Rolland Annelise Genoux Guillaume Combes Mikael Croyal bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group Institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'epidémiologie et de Recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'Institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy ***1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains ***,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP *** examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these ***:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were ***1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year *** linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 *** analyses were conducted to examine whether apoA-I mediated these *** linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in ***:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;Se=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;Se=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;Se=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly med

关键词： Aging Apolipoprotein Bioenergetics exerkine Mitochondria

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Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

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