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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 plants.This 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 chemistry.In particular,carbon allotropes are widely used in these composites being widely applied for medical purposes.Observing 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 nanocarbons.These 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,etc.These 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 others.Combination of various synthesis techniques can be also carried out for composite preparation.Natural 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 biomass.Resulting 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 polymers.In 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 effect.GO→G reduction and higher HA decoration were observed in several experiments.The morphology of p

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 topics.This dataset represents a versatile language resource,particularly useful for testing the ability of current machine learning models to acquire expert scientific knowledge.Despite 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 tasks.In 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 answering.As 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 shortcomings.Furthermore,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 candidates.The 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

Improvement of the software for modeling the dynamics of epidemics and developing a user-friendly interface

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Infectious Disease Modelling 2023年第3期8卷 806-821页

作者： igor Nesteruk Institute of Hydromechanics National Academy of Sciences of UkraineKyivUkraine igor Sikorsky Kyiv Polytechnic Institute KyivUkraine

The challenges humanity is facing due to the Covid-19 pandemic require timely and accurate forecasting of the dynamics of various epidemics to minimize the negative consequences for public health and the economy.One can use a variety of well-known and new mathematical models,taking into account a huge number of factors.However,complex models contain a large number of unknown parameters,the values of which must be determined using a limited number of observations,e.g.,the daily datasets for the accumulated number of cases.Successful experience in modeling the COVID-19 pandemic has shown that it is possible to apply the simplest SIR model,which contains 4 unknown parameters.Application of the original algo-rithm of the model parameter identification for the first waves of the COVID-19 pandemic in China,South Korea,Austria,Italy,Germany,France,Spain has shown its high accuracy in pre-dicting their duration and number of diseases.To simulate different epidemic waves and take into account the incompleteness of statistical data,the generalized SIR model and algorithms for determining the values of its parameters were proposed.The interference of the previous waves,changes in testing levels,quarantine or social behavior require constant monitoring of the epidemic dynamics and performing SIR simulations as often as possible with the use of a user-friendly interface.Such tool will allow predicting the dynamics of any epidemic using the data on the number of diseases over a limited period(e.g.,14 days).It will be possible to predict the daily number of new cases for the country as a whole or for its separate region,to estimate the number of carriers of the infection and the probability of facing such a carrier,as well as to estimate the number of deaths.Results of three SIR simulations of the COVID-19 epidemic wave in Japan in the summer of 2022 are presented and discussed.The predicted accumulated and daily numbers of cases agree with the results of observations,especially for the simulation based on the datasets correspo

关键词： COVID-19 pandemic epidemic waves epidemic dynamics in Japan Mathematical modeling of infection diseases SIR model Parameter identification Statistical methods

evaluating the influence of air pollution on solar radiation observations over the coastal region of Alicante(Southeastern Spain)

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Journal of environmental Sciences 2023年第4期126卷 633-643页

作者： igor Gómez Sergio Molina Juan JoséGaliana-Merino Department of Applied Physics Faculty of SciencesUniversity of AlicanteSection 99E-03080 AlicanteSpain Multidisciplinary Institute for environmental Studies(MIeS)“Ramón Margalef” University of AlicanteSection 99E-03690 AlicanteSpain Department of Physics Systems Engineering and Signal TheoryUniversity of AlicanteSection 99E-03080 AlicanteSpain University Institute of Physics Applied to Sciences and Technologies University of AlicanteSection 99E-03080 AlicanteSpain

The present study evaluates ground-based downward surface shortwave radiation (Rs) over the coastal region of Alicante (Southeastern Spain).Hourly measurements collected over the eleven-year period 2010-2020 are used.Two weather stations located over the region capital,Alicante,have been selected as representative of urban and suburban typologies.Two additional weather stations far from the city have been selected representing rural typologies.Rs is significantly reduced over the urban station during the morning hours within the winter season compared to the observations recorded over the suburban and rural stations,with a global mean difference of-81 and-120 W/m^(2)at 10 LT,respectively.However,no significant differences are obtained during the midday sun,with a global mean difference of-20 W/m^(2)between the urban and rural stations.With the aim of explaining these differences,the current paper investigates the relationship between Rsand different air pollutants:NOx,SO_(2),and fine particulate matter (PM_(2.5)and PM_(10)) as well as the wind field measured at the urban and suburban stations.The results found in this work point towards a close relationship between Rsand NOxconcentrations annual cycles,which are also influenced by the prevailing wind circulations observed over the study area.A global mean NOxconcentration of 107μg/m^(3)is observed over the urban station at 10 LT during the winter season.In contrast,these high concentrations are significantly reduced over the suburban station,with global mean value of 40μg/m^(3)at 10 LT,for this period of the year.

关键词： Solar radiation Air pollution Weather-concentration relationship Coastal cities Atmospheric conditions Wind field

New insights into the pathogenesis of primary biliary cholangitis asymptomatic stage

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世界胃肠病学杂志:英文版 2023年第37期29卷 5292-5304页

作者： Vasiliy Ivanovich Reshetnyak igor Veniaminovich Maev Department of Propaedeutics of Internal Diseases and Gastroenterology A.I.Yevdokimov Moscow State University of Medicine and DentistryMoscow 127473Russia

Primary biliary cholangitis(PBC)is a chronic cholestatic progressive liver disease and one of the most important progressive cholangiopathies in adults.Damage to cholangiocytes triggers the development of intrahepatic cholestasis,which progresses to cirrhosis in the terminal stage of the disease.Accumulating data indicate that damage to biliary epithelial cells[(BeCs),cholangiocytes]is most likely associated with the intracellular accumulation of bile acids,which have potent detergent properties and damaging effects on cell membranes.The mechanisms underlying uncontrolled bile acid intake into BeCs in PBC are associated with pH change in the bile duct lumen,which is controlled by the bicarbonate(HCO3-)buffer system“biliary HCO3-umbrella”.The impaired production and entry of HCO3-from BeCs into the bile duct lumen is due to epigenetic changes in expression of the X-linked microRNA 506.Based on the growing body of knowledge on the molecular mechanisms of cholangiocyte damage in patients with PBC,we propose a hypothesis explaining the pathogenesis of the first morphologic(ductulopenia),immunologic(antimitochondrial autoantibodies)and clinical(weakness,malaise,rapid fatigue)signs of the disease in the asymptomatic stage.This review focuses on the consideration of these mechanisms.

关键词： Primary biliary cholangitis Antimitochondrial autoantibodies MicroRNA 506 Inositol-1,4,5-trisphosphate receptor type 3 Chloride/bicarbonate anion exchanger 2 Biliary bicarbonate umbrella Dihydrolipoyl transacetylase(e2 subunit) Pyruvate dehydrogenase complex

The left-right side-specific endocrine signaling:implications for neurological deficits in stroke and neurodevelopmental disorders

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Neural Regeneration Research 2022年第11期17卷 2431-2433页

作者： Georgy Bakalkin Nikolay Lukoyanov igor Lavrov Mengliang Zhang Department of Pharmaceutical Biosciences Uppsala University Departamento de Biomedicina da Faculdade de Medicina da Universidade do Porto Instituto de Investiga??o e Inova??o em SaúdeInstituto de Biologia Molecular e Celular Department of Neurology Mayo Clinic Department of Molecular Medicine University of Southern Denmark

Brain injury-induced neurological deficits typically develop on the contralateral side of the body and include abnormal posture,motor weakness,and spasticity.It is believed that the interruption of descending neural p... 详细信息

关键词： neurological typically deficit

Business Continuity Management,Operational Resilience,and Organizational Resilience:Commonalities,Distinctions,and Synthesis

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International Journal of Disaster Risk Science 2023年第5期14卷 713-721页

作者： S.e.Galaitsi elizaveta Pinigina Jeffrey M.Keisler Gianluca Pescaroli Jesse M.Keenan igor Linkov US Army engineer Research and Development Center VicksburgMS39180USA College of Management University of Massachusetts BostonBostonMA02125USA Institute for Risk and Disaster Reduction University College LondonLondonWC1E 6BTUK School of Architecture Tulane UniversityNew OrleansLA70118USA

The concepts of business continuity management,operational resilience,and organizational resilience each refer to actions that businesses and organizations can take in anticipating and responding to disruptions.However,the existing definitions and usages are difficult to differentiate due to overlapping objectives,implementation processes,and outcomes.This article examines definitions and approaches for these three concepts and suggest a framework to operationalize methods and tools relevant to each.These definitions emphasize three dyads:risk versus resilience;organizational processes versus assets;and normal operating conditions versus crisis conditions.Using these dyads to differentiate the concepts of business continuity management,operational resilience,and organizational resilience can support planners in clarifying objectives and identifying which approach will be most beneficial as businesses or organizations plan for and encounter disruptions.This article evaluates these concepts by examining illustrative examples of disruptions and responses.

关键词： Business continuity management Disruptions Operational resilience Organizational resilience

Persistent half-metallic ferromagnetism in a(111)-oriented manganite superlattice

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npj Computational Materials 2022年第1期8卷 727-734页

作者： Fabrizio Cossu Heung-Sik Kim Biplab Sanyal igor Di Marco Department of Physics and Institute of Quantum Convergence and Technology Kangwon National UniversityChuncheon24341Korea Asia Pacific Center for Theoretical Physics Pohang37673Korea Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120UppsalaSweden Department of Physics POSTECHPohang37673Korea

We employ electronic structure calculations to show that a(111)-oriented(LaMnO_(3))_(12)∣(SrMnO_(3))_(6)superlattice retains a half-metallic ferromagnetic character despite its large thickness.We link this behaviour to the strain and the octahedral connectivity between the layers.This also gives rise to breathing modes,which are coupled to charge and spin oscillations,whose components have a pure e_(g)character.Most interestingly,the magnetisation reaches its maximum value inside the LaMnO_(3)region and not at the interface,which is fundamentally different from what observed for the(001)orientation.The inter-atomic exchange coupling shows that the magnetic order arises from the double-exchange mechanism,despite competing interactions inside the SrMnO_(3)region.Finally,the van Vleck distortions and the spin oscillations are crucially affected by the variation of Hund’s exchange and charge doping,which allows us to speculate that our system behaves as a Hund’s metal,creating an interesting connection between manganites and nickelates.

关键词： metallic exchange superlattice