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gut microbiota-related complications in cirrhosis

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World Journal of gastroenterology 2014年第42期20卷 15624-15631页

作者： Isabel gómez-Hurtado José Such Yolanda Sanz Rubén francés CIBERehd-Liver Unit Hospital General Universitario Alicante Instituto de Agroquímica y Tecnología de los Alimentos Consejo Superior de Investigaciones Científicas (IATACSIC) Carrer Catedràtic Agustín Escardino Benlloch

gut microbiota plays an important role in cirrhosis. The liver is constantly challenged with commensal bacteria and their products arriving through the portal vein in the so-called gut-liver axis. Bacterial translocation from the intestinal lumen through the intestinal wall and to mesenteric lymph nodes is facilitated by intestinal bacterial overgrowth, impairment in the permeability of the intestinal mucosal barrier, and deficiencies in local host immune defences. Deranged clearance of endogenous bacteria from portal and systemic circulation turns the gut into the major source of bacterialrelated complications. Liver function may therefore be affected by alterations in the composition of the intestinal microbiota and a role for commensal flora has been evidenced in the pathogenesis of several complications arising in end-stage liver disease such as hepatic encephalopathy, splanchnic arterial vasodilatation and spontaneous bacterial peritonitis. The use of antibioticsis the main therapeutic pipeline in the management of these bacteria-related ***,other strategies aimed at preserving intestinal homeostasis through the use of pre-,pro-or symbiotic formulations are being studied in the last *** this review,the role of intestinal microbiota in the development of the most frequent complications arising in cirrhosis and the different clinical and experimental studies conducted to prevent or improve these complications by modifying the gut microbiota composition are summarized.

关键词： Cirrhosis Encephalopathy Portal hypertension Spontaneous bacterial peritonitis Microbiota Bacterial translocation

The storage and utilization of carbohydrates in response to elevation mediated by tree organs in subtropical evergreen broad-leaved forests

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Forest Ecosystems 2024年第1期11卷 52-61页

作者： Bin Xu Xueli Jiang Yingying Zong g.geoff Wang Fusheng Chen Zhenyu Zhao Xiangmin Fang Key Laboratory of National Forestry and grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang330045China Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem College of ForestryJiangxi Agricultural UniversityNanchang330045China Department of Forestry and Environmental Conservation Clemson UniversityClemsonSC29634USA

global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change *** effect of elevation on tree growth may depend on organ ***,the allocation patterns of nonstructural and structural carbohydrates(Nscs and scs,respectively)in different tree organs and their response to elevation remain *** selected four dominant tree species,schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root Nscs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of *** Nscs increased initially and then decreased,and trunk Nscs increased with increasing ***,root Nscs decreased with increasing *** relative abundance of scs in leaves and trunks decreased,while the relative abundance of root scs increased with increasing *** significant correlations between scs and Nscs in leaves were detected,while there were negative correlations between scs and Nscs in trunks,roots,and all *** partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in scs and *** results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of *** results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.

关键词： Nonstructural carbohydrates Structural carbohydrates Elevation Subtropical evergreen broad-leaved forests Tree organs

Removing Splitting/Modeling Error in Projection/Penalty Methods for Navier-Stokes Simulations with Continuous Data Assimilation

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Communications in Mathematical Research 2024年第1期40卷 1-29页

作者： Elizabeth Hawkins Leo g.Rebholz Duygu Vargun Department of Mathematical sciences Clemson UniversityClemsonSC 29634USA

We study continuous data assimilation(CDA)applied to projection and penalty methods for the Navier-Stokes(NS)*** and projection methods are more efficient than consistent Ns discretizations,however are less accurate due to modeling error(penalty)and splitting error(projection).We show analytically and numerically that with measurement data and properly chosen parameters,CDA can effectively remove these splitting and modeling errors and provide long time optimally accurate solutions.

关键词： Navier-Stokes equations projection method penalty method continuous data assimilation

Applications of Soft Computing Methods in Backbreak Assessment in Surface Mines: A Comprehensive Review

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Computer Modeling in Engineering & sciences 2024年第9期140卷 2207-2238页

作者： Mojtaba Yari Manoj Khandelwal Payam Abbasi Evangelos I.Koutras Danial Jahed Armaghani Panagiotis g.Asteris Department of Mining Engineering Faculty of EngineeringMalayer UniversityMalayer***Iran Institute of Innovation Science and SustainabilityFederation University AustraliaBallaratVIC 3350Australia Marane Olia Ornamental Stone Mine Sanandaj***Iran Computational Mechanics Laboratory School of Pedagogical and Technological EducationAthens15122Greece school of Civil and Environmental Engineering University of Technology SydneySydneyNSW 2007Australia

geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them *** Computing(sc)methods have gained popularity in engineering disciplines such as mining and civil engineering due to computer hardware and machine learning *** traditional hard computing approaches,sc models use soft values and fuzzy sets to navigate uncertain *** study focuses on the application of sc methods to predict backbreak,a common issue in blasting operations within mining and civil ***,which refers to the unintended fracturing of rock beyond the desired blast perimeter,can significantly impact project timelines and *** study aims to explore how sc methods can be effectively employed to anticipate and mitigate the undesirable consequences of blasting operations,specifically focusing on backbreak *** research explores the complexities of backbreak prediction and highlights the potential benefits of utilizing sc methods to address this challenging issue in geo-engineering projects.

关键词： Backbreak blasting soft computing methods prediction theory-guided machine learning

Enzymatic Synthesis of Polycaprolactone:Effect of Immobilization Mechanism of CALB on Polycaprolactone Synthesis

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Journal of Renewable Materials 2018年第6期6卷 619-629页

作者： Yasemin Kaptan.M.sc Yüksel Avcıbaşı-güvenilir Istanbul Technical University Department of Chemical EngineeringIstanbul Technical University34469Maslak-Istanbul

Surface-modified rice husk ash was used as an inorganic support material for immobilization of Candida antarctica lipase B.(3-aminopropyl)trimethoxysilane was used for surface *** of CALB was performed via both physical adsorption and *** synthesis was carried out by using these immobilized enzymes,free enzyme and Novozyme 435®.Molecular weight distribution of polymer samples was obtained by gel permeation chromatography(gPC)and chain structures of the polymer samples were observed by hydrogen nuclear magnetic resonance(1H-NMR).The highest monomer conversion is generally obtained by using cross-linked enzyme,around 90%.PDI values for all polymer samples were approximately 1.5 which can be considered as *** general cross-linked enzymes were better than physically adsorbed enzymes in terms of average molecular *** can be concluded that PCL can be synthesized with these immobilized enzymes with high molecular weight and low PDI values.

关键词： Candida antarctica lipase B cross-linking physical adsorption Polycaprolactone rice husk ash

Solidification of Be-free Ni-based dental alloy

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Transactions of Nonferrous Metals Society of China 2018年第11期28卷 2227-2236页

作者： franc ZUPANIC Carlos A.NUNES gilberto C.COELHO Paula L.CURY gorazd LOJEN Tonica BONCINA Faculty of Mechanical Engineering University of Maribor2000 MariborSlovenia Department of Materials Engineering School of EngineeringUniversity of Sao Paulo12602-810 LorenaSao PauloBrazil

A novel, Nb- and Si-rich and Be-free Ni-based alloy was cast by two methods of investment casting and continuouscasting to study the microstructure evolution during solidification and its mechanical properties. The solidification of the alloy startedwith the primary crystallization of FCC-γ, followed by a binary eutectic reaction, with the formation of a heterogeneous constituent：FCC-γ＋g-phase, which replaced the low-melting eutectic （FCC-γ＋NiBe） in the Be-bearing alloys. AlNi6Si3 and γ′ formed during theterminal stages of solidification by investment casting, while the formation of AlNi6Si3 was suppressed by continuous casting. Thescheil solidification model agreed very well with the experimental results.

关键词： solidification nickel alloy continuous casting investment casting microstructure dental alloy

glycerol Electrooxidation over Precision-Synthesized gold Nanocrystals with Different Surface Facets

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Precision Chemistry 2024年第3期2卷 103-111页

作者： Hansen Mou Fang Lu Zechao Zhuang Qiaowan Chang Lihua Zhang Xiaobo Chen Yugang Zhang Jingguang g.Chen Department of Chemical Engineering Columbia UniversityNew YorkNew York 10027United States school of Chemical Engineering and Bioengineering Washington State UniversityPullmanWashington 99164United States Center for Functional Nanomaterials Brookhaven National LaboratoryUptonNew York 11973United States Materials science and Engineering Program State University of New York at BinghamtonBinghamtonNew York 13902United States Chemistry Division Brookhaven National LaboratoryUptonNew York 11973United States

Electrochemical glycerol oxidation(EgO)emerges as a promising route to valorize glycerol,an underutilized byproduct from biodiesel production,into value-added *** study employed three types of gold(Au)nanocrystals with controlled shapes to elucidate the facet-dependent electrocatalytic behavior in ***,rhombic dodecahedral,and cubic Au nanocrystals with{111},{110},and{100}facets,respectively,were precisely synthesized with uniform size and *** dodecahedra exhibited the lowest onset potential for EgO due to facile AuOH formation,while octahedra showed enhanced electrochemical activity for glycerol oxidation and resistance to ***-situ FTIR analysis revealed that Au{111}surfaces selectively favored C_(2) products,whereas Au{100}surfaces promoted C_(3) product formation,highlighting the significant effect of facet orientation on EgO performance and informing catalyst design.

关键词： Electrochemical glycerol oxidation Precision synthesis Shaped nanocrystals Au nanocrystals SAXS In-situ FTIR

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov Aleksey V.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkova Evgeniy A.Kolesnikov Elena A.Straumal Inna O.gozhikova Saidkhodzha g.Nematulloev Dmitry V.Telyshev Institute of Physiologically Active Compounds of the Russian Academy of sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National University of science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which provided special conditions for the crystallization of dissolved UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were investigated by scanning electron microscopy(SEM) and differential scanning calorimetry(Dsc). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an oval shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) gives the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

Two Novel Sesquiterpene Diglycosides from Dictamnus dasycarpus

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Chinese Chemical Letters 1999年第7期10卷 563-566页

作者： Zhao, WM Wang, sc Hostettmann, K Qin, gW Xu, RS Chinese Acad sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China Univ Lausanne Coll Pharm CH-1015 Lausanne Switzerland

Two novel sesquiterpene diglycosides named dictamnosides F 1 and g 2 were isolated from methanol extract of the root bark of Dictamnus dasycarpus. Their structures were determined on the basis of spectroscopic and che... 详细信息

关键词： Dictamnus dasycarpus Rutaceae dictamnosides F and g sesquiterpene diglycosides