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structural modification of titanium surface by octacalcium phosphate via Pulsed Laser deposition and chemical treatment

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Bioactive Materials 2017年第2期2卷 101-107页

作者： I.V.smirnov J.V.Rau M.Fosca a.de Bonis A.Latini R.Teghil V.I.Kalita A.Yu.Fedotov s.V.Gudkov A.E.Baranchikov V.s.Komlev A.Abaikov institute of metallurgy and materials science russian academy of sciencesleninsky prospect 49119334 moscowrussia istituto di struttura.della materia consiglio nazionale delle ricerchevia del fosso del cavaliere 10000133 romeitaly dipartimento di scienze universita della basilicataviale dell'ateneo lucano1085100 potenzaitaly universita di roma“la sapienza” dipartimento di chimicapiazzale aldo moro500185 romeitaly lobachevsky state university gagarin av5.23603950 nizhny novgorodrussia prokhorov institute of general physics russian academy of sciencesvavilova street38119991 moscowrussia institute of theoretical and experimental biophysics russian academy of sciencesinstitutskaya street3pushchino142290 moscow regionrussia kurnakov institute of general and inorganic chemistry of the russian academy of sciences leninsky prospect 31119991 moscowrussia

In the present study, the Pulsed Laser deposition (PLD) technique was applied to coat titanium for orthopaedicand dental implant applications. Calcium carbonate (CC) was used as starting coating *** deposited CC films were transformed into octacalcium phosphate (OCP) by chemical treatments. Theresults of X-ray diffraction (XRD), Raman, Fourier Transform Infrared spectroscopy (FTIR) and scanningelectron microscopy (sEM) studies revealed that the final OCP thin films are formed on the titaniumsurface. Human myofibroblasts from peripheral vessels and the primary bone marrow mesenchymalstromal cells (BMMss) were cultured on the investigated materials. It was shown that all the investigatedsamples had no short-term toxic effects on cells. The rate of division of myofibroblast cells growing onthe surface and saturated BMMss concentration for the OCP coating were about two times faster than ofcells growing on the CC films.

关键词： Titanium implants Coating Pulsed Laser deposition Calcium carbonate Octacalcium phosphate

Microcalorimetric study of Acetylcholine and Acetylthiocholine Hydrolysis by Acetylcholinesterase

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Advances in Enzyme Research 2017年第1期5卷 1-12页

作者： Paulo Alexandre a.de Almeida Neves Eliane Novato silva Paulo s.L.Beirao Biochemistry and Immunology department Federal University of Minas GeraisBelo HorizonteBrazil

Acetylcholinesterase (AChE) is an important enzyme responsible for the cleavage of acetylcholine. studies of the activity of this enzyme use an artificial substrate, acetylthiocholine, because a product of its catalysis, thiocholine, readily generates a light absorbing product upon reaction with Elman’s reagent 5,5’-dithiobis-(2-nitrobenzoic acid (DTNB). The hydrolysis of acetylcholine cannot be assayed with this method. The isothermal titration calorimetry can assay the hydrolysis of both substrates, without requiring additional reagents other than the enzyme and the substrate. To compare kinetic values obtained in the hydrolysis of acetylcholine (ACh) and acetylthiocholine (ATCh), with carbaryl acting as inhibitor, a calorimetric technique was used to evaluate kinetic properties of the two reactions. This method can show the hydrolysis of both substrates by the heat exchange that occurs during catalysis. In addition, it allowed the assessment of the AChE inhibition by carbaryl, a common insecticide. The results show a similarity between values obtained with both substrates, which are slightly higher for acetylcholine, the enzyme natural substrate. Enzymatic parameters values from ATCh and ACh were similar to each other and inhibitory constants using carbaryl were also similar, displaying that any approach to ACh is feasible using ATCh. The results obtained from ITC show the precision achieved by the calorimetric method.

关键词： Acetylcholinesterase Acetylcholine Acetylthiocholine Isothermal Titration Calorimetry Carbaryl

Duodenum-preserving local excision of a gastrointestinal stromal tumor

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Hepatobiliary & Pancreatic Diseases International 2008年第2期7卷 214-216页

作者： Chandika AH liyanage sanjaya Abeygunawardhana sumudu Kumarage Kemal I deen department of surgery University of Kelaniya Medical School Ragama Sri Lanka

BACKGROUND:Duodenal gastrointestinal stromal tumors (GIsTs) are rare. Because of the complex anatomy of the duodenum, the methods of resection of these tumors are controversial and diverse. METHODs:We report a case of a duodenal GIsT in the anterolateral wall of the second part of the duodenum, which was successfully managed by local excision. The surgery was facilitated by preoperative mapping with Indian ink and navigation by endoscopy to assess the adequacy of resection and to avoid injury to the ampulla. REsULT:Reconstruction was successful with a duodeno-jejunostomy and protected by a nasoduodenal drain. CONCLUsION:The patient had no postoperative complications and the tumor was confirmed to be a GIsT of the duodenum successful with an adequate resection margin.

关键词： gastrointestinal stromal tumor local excision, duodenum

In vivo study of conductive 3D printed PCL/MWCNTs scaffolds with electrical stimulation for bone tissue engineering

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Bio-design and Manufacturing 2021年第2期4卷 190-202页

作者： Edney P.e silva Boyang Huang Júlia V.Helaehil Paulo R.L.Nalesso Leonardo Bagne Maraiara a.de Oliveira Gabriela C.C.Albiazetti Ali Aldalbahi Mohamed El-Newehy Milton santamaria-Jr Fernanda A.s.Mendonça Paulo Bártolo Guilherme F.Caetano Postgraduate Program in Biomedical sciences University Center of Hermínio Ometto Foundation-FHOArarasSao PauloBrazil department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringUniversity of ManchesterManchester M139PLUK King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh 11451Saudi Arabia

Critical bone defects are considered one of the major clinical challenges in reconstructive bone *** combination of 3D printed conductive scaffolds and exogenous electrical stimulation(Es)is a potential favorable approach for bone tissue *** this study,3D conductive scaffolds made with biocompatible and biodegradable polycaprolactone(PCL)and multi-walled carbon nanotubes(MWCNTs)were produced using the extrusion-based additive manufacturing to treat large calvary bone defects in *** results show that the use of PCL/MWCNTs scaffolds and Es contributes to thicker and increased bone tissue formation within the bone *** and mineralization are also significantly promoted using high concentration of MWCNTs(3 wt%)and ***,scaffolds favor the tartrate-resistant acid phosphatase(TRAP)positive cell formation,while the addition of MWCNTs seems to inhibit the osteoclastogenesis but present limited effects on the osteoclast functionalities(receptor activator of nuclear factor κβ ligand(RANKL)and osteoprotegerin(OPG)expressions).The use of Es promotes the osteoclastogenesis and RANKL expressions,showing a dominant effect in the bone remodeling *** results indicate that the combination of 3D printed conductive PCL/MWCNTs scaffold and Es is a promising strategy to treat critical bone defects and provide a cue to establish an optimal protocol to use conductive scaffolds and Es for bone tissue engineering.

关键词： Additive manufacturing Bone regeneration Bone remodeling Carbon nanotube Conductive scaffolds Electrical stimulation

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： s.sAURABH R.KIRAN D.sINGH R.VAIsH V.s.CHAUHAN school of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHsDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(Hs), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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semantic segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on spine Magnetic Resonance Images

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Computer Modeling in Engineering & sciences 2025年第1期142卷 733-757页

作者： Lakshmi s V V shiloah Elizabeth Darmanayagam sunil Retmin Raj Cyril department of Computer science and Engineering College of Engineering GuindyAnna UniversityChennai600025India department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a.detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expa.ded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DsC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer a.ded diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

Predicting Maximum Lifespan Limits at Mean Menopausal Age

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Journal of Mathematical Research with Applications 2025年第1期 133-142页

作者： M.sUMATHI s.ANTONY CARLA department of Mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. Menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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Correlating the electronic structure of perovskite La_(1-x)srxCoO_(3) with activity for the oxygen evolution reaction:The critical role of Co 3d hole state

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Journal of Energy Chemistry 2022年第2期31卷 637-645页

作者： Zechao shen Mei Qu Jueli shi Freddy E.Oropeza Victor a.de la Peña O’shea Giulio Gorni C.M.Tian Jan P.Hofmann Jun Cheng Jun Li Kelvin H.L.Zhang state Key Laboratory of Physical Chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Photoactivated Processes Unit IMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain CELLs-ALBA synchrotron Carrer de la Llum 2-2608290 Cerdanyola del VallèsSpain surface science Laboratory Department of Materials and Earth SciencesTechnical University of Darmstadt Otto-Berndt-Strasse 364287 DarmstadtGermany

Perovskite LaCoO_(3) is being increasingly explored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).sr doping in LaCoO_(3)(La1-xsrxCoO_(3))has been found to substantially increase its catalytic *** this work,we report a.detailed study on the evolution of the electronic structure of La1-xsrxCoO_(3) with 0≤x≤1 and its correlation with electrocatalytic activity for the OER.A combination of X-ray photoemission spectroscopy(XPs)and X-ray absorption spectroscopy(XAs)was used to unravel the electronic density of states(DOs)near the Fermi level(EF),which provide insights into the key electronic structure features for the enhanced OER catalytic *** analysis on the Co L-edge XAs suggest that LaCoO_(3) has a low spin state with t_(2g)^(6) e_(g)^(0) configuration at room *** implies that the high OER catalytic activity of LaCoO_(3) should not be rationalized by the occupancy of eg=1 *** sr^(2+) for La^(3+) in LaCoO_(3) induces Co4+oxidation states and effectively dopes hole states into the top of valence band.A semiconductor-to-metal transition is observed for x>0.2,due to the holeinduced electronic DOs at the EF and increased hybridization between Co 3 d and O 2 *** an electronic modulation enhances the surface adsorption of the*OH intermediate and reduces the energy barrier for interfacial charge transfer,thus improving the OER catalytic activity in La_(1-x)sr_(x)CoO_(3).In addition,we found that the La_(1-x)sr_(x)CoO_(3) surface undergoes amorphization after certain period of OER measurement,leading to a partial deactivation of the *** sr doping levels accelerated the amorphization process.

关键词： Perovskite oxide Oxygen evolution Cobalt Electronic structure

Physical exercise and COVID-19 pa.demic in PubMed:Two months of dynamics and one year of original scientific production

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sports Medicine and Health science 2021年第2期3卷 80-92页

作者： Rodrigo L.Vancini Marília s.Andrade Ricardo B.Viana Pantelis T.Nikolaidis Beat Knechtle Cassia R.V.Campanharo Alexandre a.de Almeida Paulo Gentil Claudio A.B.de Lira Centro de Educaçao Física e desportos(CEFD) Universidade Federal do Espírito Santo(UFES)Espírito Santo(ES)Brazil departamento de Fisiologia Universidade Federal de Sao Paulo(UNIFESP)Sao Paulo(SP)Brazil setor de Fisiologia Humana e do Exercício Faculdade de Educaçao Física e DançaUniversidade Federal de Goias(UFG)GoianiaGoias(GO)Brazil school of Health and Caring sciences University of West AtticaGreece Medbase st.Gallen Am Vadianplatz St.Gallen and Institute of Primary CareUniversity of ZurichZurichSwitzerland Escola Paulista.de Enfermagem(EPE) UNIFESPSao Paulo(SP)Brazil Instituto Federal de Educaçao Ciencia e Tecnologia do Tocantins(IFTO Araguatins)Campus Araguatins.Povoado Santa TerezaKm 05 S/N Zona RuralAraguatinsTocantins(TO)Brazil

Our aim was to conduct a narrative review about physical exercise and Corona Virus Disease 2019(COVID-19).A literature search was completed crossing the keywords“COVID-19”and“physical exercise”,for a narrative re-view,and physical activity(PA),physical exercise,physical training,sport,physical fitness,for a systematic re-view;search strategy(Randomized Controlled Trial,in the last 1 year,English).The first search date was closed on 04/26/2020 and 06/26/*** strategy was chosen to assess the dynamics of scientific information production for the *** two months,an increase of 76%,from 12(19.4%)to 50(80.64%)COVID-19 articles(n=62,100%)was *** main types of articles published were editorial articles(16.13%,n=10 of 62 articles)and commentary(9.68%,n=6 of 62 articles).The most frequent country of origin of the scientific production was the United states(12.90%,n=8 of 62 articles),the United Kingdom(12.90%,n=8 of 62 arti-cles),and Brazil(11.29%,n=7 of 62 articles).However,in 2020,there were only 2 relevant randomized controlled trials on the COVID-19 topic in the context of physical *** information production shows the concern of the PA science community to bring a solution to the increase in physical inactivity generated by the COVID-19 *** findings show the dynamics of scientific production on the COVID-19,in a situation so unique such as a pa.demic,denotes that the practice of PA is essential to improve and/or maintain physical and mental health.

关键词： Coronavirus Pa.demic COVID-19 social isolation Quarantine Physical exercise Physical activity sport