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Finding my way: The role of dirigent proteins in lignin assembly

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Molecular Plant 2024年第2期17卷 230-232页

作者： Dyoni M.Oliveira igor Cesarino Department of Plant Biotechnology and Bioinformatics Ghent University9052 GhentBelgium VIB Center for Plant Systems Biology 9052 GhentBelgium Departamento de Botanica Instituto de BiocienciasUniversidade de Sao PauloRua do Matao277Sao Paulo 05508-090Brazil Synthetic and Systems Biology Center InovaUSPAvenida Professor Lucio Martins Rodrigues370SaoPaulo 05508-020Brazil

Lignin emerged around 450 million years ago in early tracheophytes and played a pivotal role in the colonization of terrestrial ecosystems by *** aromatic biopolymer provides mechanical strength to supportive tissues and hydrophobicity to water-transporting vasculature and acts as a physical barrier against herbivores and pathogens(Renault et al.,2019).The deposition of lignin in cell walls for proper cellular functionalization involves several molecular steps,including the tight regulation of tissue-or cell-type-specific expression of lignin biosynthetic genes,the biosynthesis of distinct lignin monomers and their transportation to the apoplast,and the polymerization of monomer radicals to produce tissue-or cell-type-dependent polymers with distinct physico-chemical properties.

关键词： properties. lignin walls

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.González Yolanda Peña Méndez igor e.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

Benchmarks for Pirá2.0,a Reading Comprehension Dataset about the Ocean,the Brazilian Coast,and Climate Change

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Data Intelligence 2024年第1期6卷 29-63页

作者： Paulo Pirozelli Marcos M.José igor Silveira Flávio Nakasato Sarajane M.Peres Anarosa A.F.Brandão Anna H.R.Costa Fabio G.Cozman Universidade de São Paulo Ringgold Standard Institution-Instituto de estudos Avançados Av.370 São Paulo 05508-900Brazil Universidade de São Paulo Ringgold Standard Institution-Instituto de Matemática e estatística Av.370 São Paulo 05508-900Brazil Universidade de São Paulo Rua Cayowaá876 apto 141SÃO PAULO 05018-001Brazil Universidade de São Paulo Ringgold Standard Institution Escola Politécnica Av.370São Paulo 05508-900Brazil.

Piráis a reading comprehension dataset focused on the ocean,the Brazilian coast,and climate change,built from a collection of scientific abstracts and reports on these *** dataset represents a versatile language resource,particularly useful for testing the ability of current machine learning models to acquire expert scientific *** its potential,a detailed set of baselines has not yet been developed for Pirá.By creating these baselines,researchers can more easily utilize Piráas a resource for testing machine learning models across a wide range of question answering *** this paper,we define six benchmarks over the Pirádataset,covering closed generative question answering,machine reading comprehension,information retrieval,open question answering,answer triggering,and multiple choice question *** part of this effort,we have also produced a curated version of the original dataset,where we fixed a number of grammar issues,repetitions,and other ***,the dataset has been extended in several new directions,so as to face the aforementioned benchmarks:translation of supporting texts from english into Portuguese,classification labels for answerability,automatic paraphrases of questions and answers,and multiple choice *** results described in this paper provide several points of reference for researchers interested in exploring the challenges provided by the Pirádataset.

关键词： Natural language processing Question answering Benchmarks Language resource DomainOriented dataset Scientific knowledge text dataset

Physico-chemical characterization of acid base disorders in patients with COVID-19:A cohort study

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World Journal of Nephrology 2024年第2期13卷 16-23页

作者： Sergio Pinto de Souza Juliana R Caldas Marcelo Barreto Lopes Marcelo Augusto Duarte Silveira Fernanda Oliveira Coelho igor Oliveira Queiroz Pedro Domingues Cury Rogério da Hora Passos Department of Nephrology Hospital São RafaelSalvadorBA 41253190Brazil Department of Nephrology D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Faculty of Medicine Escola Bahiana de Medicina e Saúde Pública-EBMSPSalvadorBA 40290000Brazil Department of Intensive Care D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Hospital São Rafael D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Department of Intensive Care Unit Hospital Israelita Albert EinsteinSao PauloSP 05652900Brazil

BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis *** a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital *** To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor *** This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography *** and clinical data were obtained from electronic *** variables were compared using Fisher’s exact *** data were presented as median and interquartile *** Mann-Whitney U test was used for *** In total,211 patients were *** mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus *** those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory *** non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score *** did not find severe acid-base imbalance in this *** analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not d

关键词： COVID-19 Physicochemical approach Acid-base status Critically ill patients Acute respiratory syndrome

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熵增工程在电催化反应中的研究进展

物理化学学报 2024年第7期40卷 36-42页

作者：张新义任楷刘妍宁谷振一黄志雄郑硕航王晓彤郭晋芝 igor V.Zatovsky 曹峻鸣吴兴隆东北师范大学化学学院长春130024 东北师范大学紫外光发光材料与技术教育部重点实验室长春130024 乌克兰国家科学院生物胶体化学研究所乌克兰基辅03142

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为... 详细信息

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为低熵材料(ΔS_(mix)1.5R)。随着熵值的增加,材料本征的物理与化学性质也会随之发生相应的变化。得益于不同金属元素的共存,在界面处原子级的多组分排列,所产生的协同性高熵效应能够有效地提升电催化反应的活性,因此在电催化领域中得到了广泛的研究关注。本综述对高熵电催化剂的基本概念、合成路线(“自上而下”与“自下而上”)以及在不同电催化反应类型中的高熵材料结构与性能之间的构效关系进行了系统总结,主要包括析氢(HeR)、析氧(OeR)、氧还原(ORR)、醇氧化(AOR)、氮还原(NRR)和二氧化碳还原反应(CO_(2)RR)等,从而阐明熵增工程对高性能电催化剂设计与应用的优势与潜力。同时,针对目前高熵催化剂研究所面临的主要问题与挑战,对未来基于熵增工程的高熵电催化剂的设计思路与合成方法进行展望。

关键词：熵增合成电化学高熵催化剂电催化

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On character sums with determinants

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Science China Mathematics 2023年第12期66卷 2693-2714页

作者： etienne Fouvry igor e.Shparlinski CNRS Laboratoire de Mathématiques d'OrsayUniversité Paris-SaclayOrsay 91405France School of Mathematics and Statistics University of New South WalesSydneyNSW 2052Australia

We estimate weighted character sums with determinants ad-bc of 2×2 matrices modulo a prime p with entries a,b,c and d vary ing over the interval [1,N].Our goal is to obtain non-trivial bounds for values of N as small as *** particular,we achieve this goal,with a power saving,for N≥p^(1/8+ε) with any fixed ε>0,which is very likely to be the best possible unless the celebrated Burgess bound is improved,By other techniques,we also treat more general sums but sometimes for larger values of N.

关键词： character sum determinant Burgess bound

Metal-containing nanomaterials as lubricant additives: State-of-the-art and future development

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Friction 2019年第2期7卷 93-116页

作者： igor e.UFLYAND Vladimir A.ZHINZHILO Victoria e.BURLAKOVA Department of Chemistry Southern Federal University Department of Chemistry Don State Technical University

This review focuses on the effect of metal-containing nanomaterials on tribological performance in oil lubrication. The basic data on nanolubricants based on nanoparticles of metals, metal oxides, metal sulfides, nanocomposities, and rare-earth compounds are generalized. The influence of nanoparticle size, morphology, surface functionalization, and concentration on friction and wear is analyzed. The lubrication mechanisms of nanolubricants are discussed. The problems and prospects for the development of metal-containing nanomaterials as lubricant additives are considered. The bibliography includes articles published during the last five years.

关键词： coefficient of friction metal-containing nanomaterials nanolubricants nanoparticles wear

Risk Assessment of a Stochastic Service System

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Journal of Systems Science and Systems engineering 2020年第5期29卷 537-554页

作者： igor Lazov Faculty of Informatics European University Skopje1000 SkopjeMacedonia

A stochastic service system of finite size M is comprised of identical service facilities,including or not a waiting queue,which simultaneously treats N customers,N∈{0,1,…,M}.Depending on the concepts of system information *** system entropy S=£(f),we promote a risk assessment *** definition,the system entropy is the uncertainty associated with the system,and the system expected loss is the risk associated with the ***,accepting the system information as loss function,we can identify risk and uncertainty,associated with the system,using the entropy as risk ***,we differ risk of the system(i.e.,risk observed by an outside observer),risk observed by an arriving customer,and risk observed by a departing customer,giving a separate expression for each ***,these risks are compared with each other,when the system has the same average number e(N)of customers seen by any *** three risk types(together with the three customer means)allow us to distinguish two systems obeying the same probability *** approach enables system operators to choose suitable values for system utilization and size,in view of the three risks *** developed procedure is applied to the information linear system,erlang loss system,single-server queueing system with discouraged arrivals,Binomial system and engset loss system.

关键词： Absolute and relative risk uncertainty system information and entropy system utilization stochastic service system

Dynamic magnetic hysteresis in a liquid suspension of acicular maghemite particles

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Particuology 2009年第6期7卷 451-458页

作者： Bronislav e.Kashevsky Sergey B.Kashevsky igor V.Prokhorov A.V.Luikov Heat and Mass Transfer Institute Belarus Academy of SciencesP.Brovka str.15Minsk 220072Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy absorption in a dilute suspension of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. experiments with 0.1% suspensions of acicular particles of gamma ferric oxide in solid and liquid matrices, subjected to a 430 Hz magnetic field with an intensity of up to 1200 Oe, revealed important role of particle mobility. The main qualitative and quantitative features of the phenomenon are in agreement with a model of joint magneto-mechanical dynamics of particles with a chain-of-spheres mode of incoherent magnetic reversal.

关键词： High-coercive magnetic particles Magnetic suspensions Dynamic magnetic hysteresis