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Advances in Pure Mathematics 2024年第10期14卷 785-796页

作者： Neşe İşler Acar Department of Mathematics Burdur Mehmet Akif University Burdur Turkey

In this study, the Bernstein collocation method has been expanded to Stancu collocation method for numerical solution of the charged particle motion for certain configurations of oscillating magnetic fields modelled by a class of linear integro-differential equations. As the method has been improved, the Stancu polynomials that are generalization of the Bernstein polynomials have been used. The method has been tested on a physical problem how the method can be applied. Moreover, numerical results of the method have been compared with the numerical results of the other methods to indicate the efficiency of the method.

关键词： Stancu Polynomials Collocation Method Integro-Differential Equations Linear Equation Systems Matrix Equations

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

Improved Detection of Sleeping Sickness Cases by LED Fluorescence Microscopy: Evidence from a Prospective Multi-Centric Study in the Democratic Republic of the Congo

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Microscopy Research 2015年第2期3卷 17-25页

作者： Patrick Mitashi Pascal Lutumba Crispin Lumbala Paul Bessell Sylvain Biéler Joseph Mathu Ndung’u Tropical Medicine Department Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of the Congo Programme National de Lutte contre la Trypanosomiase Humaine Africaine (PNLTHA) Croisement de l’Avenue de la Libération et du Boulevard Triomphal 1 Kinshasa Democratic Republic of the Congo Foundation for Innovative New Diagnostics (FIND) Campus Biotech Chemin des Mines 9 Geneva Switzerland

Background: Confirmatory diagnosis of Trypanosoma brucei gambiense human African trypanosomiasis (HAT) is based on demonstration of parasites by microscopy. However, the sensitivity of routine microscopy methods is very low, and many cases are missed and left untreated. A clinical study was conducted in the Democratic Republic of the Congo to evaluate the accuracy of improved microscopy methods in diagnosis of HAT. These included examination by fluorescence microscopy (FM) of acridine orange (AO) stained smears of whole blood and smears made following a new procedure for concentrating trypanosomes by selective lysis of red blood cells (RBC). Methodology/Principal Findings: Venous blood was collected from 213 HAT cases, 101 HAT suspects and 95 controls and used to determine the accuracy of four microscopy methods: bright field microscopy of Giemsa-stained thick blood smears, FM of AO-stained thick blood smears, FM of AO-stained thick blood smears prepared after RBC lysis and concentration, and FM of AO-stained thin blood smears prepared after RBC lysis and concentration. The sensitivity of FM using thick blood smears stained with AO was 3 times higher than bright field microscopy using Giemsa-stained thick blood smears [19.7% (95% CI: 14.9% - 25.6%) versus 6.1% (95% CI: 3.6% - 10.2%)]. When the RBC lysis and concentration procedure was included, sensitivity of the test was further enhanced to 23.0% (95% CI: 17.9% - 29.1%) with thick blood smears and 34.3% (95% CI: 28.2% - 40.9%) with thin blood smears. Specificity of all four microscopy methods was 100% (95% CI: 96.1% - 100.0%). However, the miniature anion exchange chromatography technique (mAECT) and capillary tube centrifugation (CTC) method remained more sensitive. Conclusions: These new methods have practical advantages, including shorter staining time, ease of demonstration of parasites, and the possibility of archiving slides. They could, therefore, be alternative methods to improve case detection where concen

关键词： Human African Trypanosomiasis Trypanosome LED Fluorescence Microscopy Red Blood Cell Lysis Diagnosis

Self-energy dynamics and the mode-specific phonon threshold effect in Kekulé-ordered graphene

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National science Review 2022年第5期9卷 81-88页

作者： Hongyun Zhang Changhua Bao Michael schüler Shaohua Zhou Qian Li Laipeng Luo Wei Yao Zhong Wang Thomas P.Devereaux Shuyun Zhou State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Stanford Institute for Materials and Energy sciences (SIMES) SLAC National Accelerator Laboratory Department of Materials science and Engineering Stanford University Institute for Advanced Study Tsinghua University Frontier science Center for Quantum Information

Electron-phonon interaction and related self-energy are fundamental to both the equilibrium properties and non-equilibrium relaxation dynamics of *** ele ctron-phonon interaction has been suggested by various time-resolved measurements to be important for the relaxation dynamics of graphene,the lack of energy-and momentum-resolved self-energy dynamics prohibits direct identification of the role of specific phonon modes in the relaxation ***,by performing time-and angle-resolved photoemission spectroscopy measurements on Kekulé-ordered graphene with folded Dirac cones at the Γ point, we have succeeded in resolving the self-energy effect induced by the coupling of electrons to two phonons at Ω=177 meV and Ω=54 meV,and revealing its dynamical change in the time ***,these strongly coupled phonons define energy thresholds,which separate the hierarchical relaxation dynamics from ultrafast,fast to slow,thereby providing direct experimental evidence for the dominant role of mode-specific phonons in the relaxation dynamics.

关键词： TrARPES self-energy electron-phonon coupling Kekulé-ordered graphene

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

Biological and mechanical investigation of novel flax/silk protein-based nanofibrous scaffold for bone regeneration

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Progress in Natural science:Materials International 2022年第4期32卷 443-455页

作者： M.Rama u.Vijayalakshmi Department of Chemistry School of Advanced Sciences Vellore Institute of Technology

The process of bone tissue regeneration involves an intricate network of a biological macromolecules that includes proteins and peptides to support stimulation and healing response. Here, we have fabricated a novel flaxseed/silk fibroin based(dual protein) composite nanofibers using β-TCP to improve the biological properties and promote cartilage tissue regeneration along with a controllable rate of biodegradation. The physiochemical properties of PVA/β-TCP/FP:SF were characterized by FTIR, XRD, SEM, porosity, contact angle measurements and mechanical evaluation etc. This study demonstrates the biological performance of the developed nanofibers by using hemocompatibility, biodegradation ability, and apatite deposition in stimulated body fluid. Moreover, the cell viability assay was performed on MG-63 osteoblast cells and long-term antibacterial rate against E. coli and S. aureus was analysed. Docking results of flax protein and silk fibroin protein further confirmed the stable modes of intramolecular bonding and the most stable electrostatic values using theoretical calculations. Taken together,the experimental results proved that the dual protein-based fibrous scaffold was found to be up-regulated in terms of biological activity with enhanced cell adhesion and proliferation.

关键词： Flax protein Silk fibroin β-TCP Electrospinning Docking Bone regeneration

Oxidative stress and lipid peroxidation products:effect of pinealectomy or exogenous melatonin injections on biomarkers of tissue damage during acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2010年第1期9卷 78-82页

作者： Cavit l Kahraman Dinler O■uz Hasdemir Oktay Büyüka■ik Güler Bu■dayci Department of General Surgery Abant Izzet Baysal University Medical School Department of Biochemistry Abant Izzet Baysal University Medical School

BACKGROuND:Melatonin (N-acetyl-5-methoxytripta-mine) is a free radical scavenger and a strong antioxidant,secreted by the pineal *** this study,we evaluated the effects of decreasing and increasing serum melatonin levels on malonyldialdehyde (MDA),superoxide dismutase (SOD),and reduced glutathione (GSH) levels in pancreatic tissue from rats with experimental acute ***:Experimental acute pancreatitis was induced in three groups of Wistar albino rats (10 animals per group) by pancreatic ductal *** first group had only acute pancreatitis and served as the *** pinealectomy was added to acute pancreatitis in the second group,removing the source of endogenous melatonin (low melatonin levels group).The third group was given 0.1 ml daily intraperitoneal injections of 20 mg/ml melatonin solution for one week (high melatonin levels group).The effects of melatonin levels were evaluated by comparison of the levels of MDA,SOD,and GS in pancreatic ***:We found that intraperitoneal melatonin injections decreased the levels of MDA and increased the levels of SOD and GSH in pancreatic ***:Exogenous melatonin has a preventive effect on lipid peroxidation and oxidative damage in acute pancreatitis.

关键词： pineal gland acute pancreatitis melatonin oxidative damage

Sodium alendronate loaded poly(L-lactideco-glycolide)microparticles immobilized on ceramic scaffolds for local treatment of bone defects

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Regenerative Biomaterials 2020年第3期7卷 293-302页

作者： Lucja Rumian Cornelia Wolf-Brandstetter Sina Roβler Katarzyna Reczynska Hanna Tiainen Havard J.Haugen Dieter scharnweber Elzbieta Pamula Faculty of Materials science and Ceramics Department of Biomaterials and CompositesAGH University of Science and TechnologyAl.A.Mickiewicza 30Krakow 30-059Poland Technische universitat Dresden Institute of Materials ScienceMax Bergmann Center of BiomaterialsBudapester Str.27Dresden 01-069Germany Department of Biomaterials Institute for Clinical DentistryUniversity of OsloGeitmyrsveien 71BlindernP.O.Box 1109Oslo NO-0317Norway

Bone tissue regeneration in critical-size defects is possible after implantation of a 3D scaffold and can be additionally enhanced once the scaffold is enriched with drugs or other factors supporting bone remodelling and *** alendronate(Aln),a widely used anti-osteoporosis drug,exhibits strong inhibitory effect on bone resorption performed by ***,we propose a new approach for the treatment of bone defects in craniofacial region combining biocompatible titanium dioxide scaffolds and poly(L-lactide-co-glycolide)microparticles(MPs)loaded with *** MPs were effectively attached to the surface of the scaffolds’pore walls by human recombinant *** release from the scaffolds was characterized by initial burst(2466% of the drug released within first 24 h)followed by a sustained release phase(on average 5 mg of Aln released per day from Day 3 to Day 18).In vitro tests evidenced that Aln at concentrations of 5 and 2.5 mg/ml was not cytotoxic for MG-63 osteoblast-like cells(viability between 8166% and 9863% of control),but it prevented RANKL-induced formation of osteoclast-like cells from macrophages derived from peripheral blood mononuclear cells,as shown by reduced fusion capability and decreased tartrateresistant acid phosphatase 5b activity(5665% reduction in comparison to control after 8 days of culture).Results show that it is feasible to design the scaffolds providing required doses of Aln inhibiting osteoclastogenesis,reducing osteoclast activity,but not affecting osteoblast functions,which may be beneficial in the treatment of critical-size bone tissue defects.

关键词： ceramic scaffolds sodium alendronate osteoblasts osteoclastogenesis collagen critical-size defect poly(L-lactideco-glycolide) microparticles

Synthesis and Crystal Structure of Trans-bis(acesulfamato-O)tetraaquazinc(Ⅱ)

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1047-1050页

作者： SAHIN Onur ICBuDAK Hasan B(u|¨)Y(u|¨)KG(u|¨)NG(O|¨)R Orhan Department of Physics Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey Department of Chemistry Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey

The title compound, trans-bis（acesulfamato-O）tetraaquazinc（Ⅱ）（I, C8H16N2O12S2Zn）, crystallizes in the triclinic system, space group P1 with a = 5.1638（5）, b = 8.5338（9）, c = 9.9583（9）A, α = 74.325（8）, β = 81.112（7）, γ = 75.800（8）°, V= 407.77（7） A3, Z = 1, F（000） = 236, Rint = 0.085, T= 296 K, the final R = 0.029 and wR = 0.078 for 1832 observed reflections with I〉 2σ（0. The ZnⅡcentre resides on a centre of symmetry and has a distorted octahedral geometry. The basal plane is defined by two carbonyl O atoms of two monodentate trans-oriented acesulfamato ligands and two trans-aqua ligands. The axial positions in the octahedron are occupied by two trans-aqua ligands. Intermolecular O-H…O hydrogen bonds produce R22（8） and R22（16） rings, which lead to two- dimensional polymeric chains.

关键词： crystal structure zinc(Ⅱ) octahedral complex hydrogen bonds

Optimized design of collector topology for offshore wind farm based on ant colony optimization with multiple travelling salesman problem

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1181-1192页

作者： Ramu SRIKAKuLAPu Vinatha u Department of Electrical and Electronics Engineering National Institute of Technology Karnataka

A layout of the offshore wind farm(OSWF)plays a vital role in its capital cost of installation. One of the major contributions in the installation cost is electrical collector system(ECS). ECS includes: submarine cables,number of wind turbines(WTs), offshore platforms etc. By considering the above mentioned problem having an optimized design of OSWF provides the better feasibility in terms of economic considerations. This paper explains the methodology for optimized designing of ECS. The proposed methodology is based on combined elitist ant colony optimization and multiple travelling salesman *** objective is to minimize the length of submarine cable connected between WTs and to minimize the wake loss in the wind farm in order to reduce the cost of cable and cable power loss. The methodology is applied on North Hoyle and Horns Rev OSWFs connected with 30 and 80 WTs respectively and the results are presented.

关键词： Ant colony optimization Offshore wind farm Multiple travelling salesman problem Wake effect Wake loss