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Geochemistry of volcanic glass from Mahanadi offshore region,eastern continental margin of India:Constraints on the contribution of latest Toba super-eruption

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Acta Oceanologica Sinica 2024年第2期43卷 111-119页

作者： Muralidhar Kocherla Durbar Ray Manavalan Satyanarayanan Hilda joao Virsen Gaikwad Pb Ramamurty CSIR-National Institute of Oceanography Dona Paula 403004GoaIndia CSIR-National Geophysical Research Institute Uppal RoadHyderabad 500007India

The tephra layers in multiple sediment cores from the offshore region of the Mahanadi basin in the northern bay of bengal were investigated for possible volcanic sources. The glass shards from those tephra layers were studied for size distribution, texture, and elemental geochemistry to establish chronostratigraphic markers for regional and global Quaternary correlation. The textural features of fine-grained(silty) volcanic glasses suggest the distal source of these tephra deposits. Major element composition with elevated SiO_(2) contents ranging between75%–76% and dominance of K_(2)O(> 4.5%) over CaO(ba volcano. The bulk trace element compositions of the same glass shards were comparable with those reported in the youngest Toba tephra reported elsewhere. Likewise, the LREE-dominated chondrite normalized REE profiles of tephra from the Mahanadi basin closely resemble the characteristic REE patterns in Toba ash from other parts of the Indian Ocean and thus confirmed the contribution of the youngest Toba super-eruption for this ash layers.

关键词： Mahanadi basin bay of bengal volcanic glass glass morphology glass-chemistry

Flexible neural probes:a review of the current advantages,drawbacks,and future demands

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Journal of Zhejiang University-Science b(biomedicine & biotechnology) 2024年第2期25卷 153-167页

作者： Sara PIMENTA joao R.FREITAS JoséH.CORREIA CMEMS-UMinho University of MinhoGuimarães4800-058Portugal LAbbELS-Associate Laboratory Braga/GuimarãesPortugal

brain diseases affect millions of people and have a huge social and economic *** use of neural probes for studies in animals has been the main approach to increasing knowledge about neural network ***,neuroscientists are trying to develop new and more effective therapeutic approaches to treating neurological *** implementation of neural probes with multifunctionalities(electrical,optical,and fluidic interactions)has been increasing in the last few years,leading to the creation of devices with high temporal and spatial *** the applicability of,and elements integrated into,neural probes has also led to the necessity to create flexible interfaces,reducing neural tissue damage during probe implantation and increasing the quality of neural acquisition *** this paper,we review the fabrication,characterization,and validation of several types of flexible neural probes,exploring the main advantages and drawbacks of these ***,future developments and applications are ***,this review aims to present the currently available flexible devices and future appropriate avenues for development as possible guidance for future engineered devices.

关键词： brain knowledge Flexible interface Multifunctional probe

Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 b from TESS

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Research in Astronomy and Astrophysics 2024年第3期24卷 129-143页

作者： Jia-Qi Wang Xiao-Jun Jiang Jie Zheng Hanna Kellermann Arno Riffeser Liang Wang Karen A.Collins Allyson bieryla Lars A.buchhave Steve b.Howell Elise Furlan Eric Girardin joao Gregorio Eric Jensen Felipe Murgas Mesut Yilmaz Sam Quinn Xing Gao Ruo-Yu Zhou Frank Grupp Hui-Juan Wang CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy Of SciencesBeijing 10010China University of Chinese Academy of Sciences Beijing 100049China University Observatory Munich Scheinertrsse 1.D-81679 MunichGemany Max Planck Institute for Extraterrestrial Physics Giessenbachstr.1D-85748 GarchingGermany National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China Center for Astrophysics Harvard&Smithsonian60 Garden Street.CambridgeMA 02138USA National Space Institute Technical University of DenmarkElektrovejDK-2800 KgsLyngbyDenmark NASA Ames Research Center Moffett FieldCA 94035USA NASA Exoplanet Science Institute Caltech/IPACMail Code 100-221200 E.California Blvd.PasadenaCA91125USA Grand Pra Observatory Switzerland Department of Physics Washington UniversitySt.LouisMO 63130.USA Department of Physics and Astronomy Swarthmore CollegeSwarthmorePA 19081USA Instituto de Astrofísica de Canarias(IAC) E-38205 La Laguna.TenerifeSpain Departamento de Astrofísica Universidad de La LagunaSpain Dept.of Astronomy and Space Sciences Ankara UniversityTandogan 06100AnkaraTurkey Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Urumqi No.1 Senior High School Urumqi 830002China Lijiang Gemini Observatory Lijiang 674199China

We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 *** candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium *** analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Objects of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period ***-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric *** measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041RJ and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 b is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(J) and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1).

关键词： planets and satellites fundamental parameters-planets and satellites gaseous planets-stars fundamental parameters-stars low-mass-methods data analysis-techniques photometric-techniques spectroscopic

Placental-derived stem cells:Culture, differentiation and challenges

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World Journal of Stem Cells 2015年第4期7卷 769-775页

作者： Maira S Oliveira joao b barreto-Filho College of Veterinary Medicine Veterinary SchoolUniversidade Federal de Minas Gerais Department of Veterinary Medicine Universidade Federal de Lavras

Stem cell therapy is a promising approach to clinical healing in several diseases. A great variety of tissues(bone marrow, adipose tissue, and placenta) arepotentially sources of stem cells. Placenta-derived stem cells(p-SCs) are in between embryonic and mesenchymal stem cells, sharing characteristics with both, such as non-carcinogenic status and property to differentiate in all embryonic germ layers. Moreover, their use is not ethically restricted as fetal membranes are considered medical waste after birth. In this context, the present review will be focused on the biological properties, culture and potential cell therapy uses of placental-derived stem cells. Immunophenotype characterization, mainly for surface marker expression, and basic principles of p-SC isolation and culture(mechanical separation or enzymatic digestion of the tissues, the most used culture media, cell plating conditions) will be presented. In addition, some preclinical studies that were performed in different medical areas will be cited, focusing on neurological, liver, pancreatic, heart, muscle, pulmonary, and bone diseases and also in tissue engineering field. Finally, some challenges for stem cell therapy applications will be highlighted. The understanding of the mechanisms involved in the p-SCs differentiation and the achievement of pure cell populations(after differentiation) are key points that must be clarified before bringing the preclinical studies, performed at the bench, to the medical practice.

关键词： Fetal membrane Placenta Embryonic stemcells Mesenchymal stem cells Cell therapy

Novel therapeutic strategies targeting mitochondria as a gateway in neurodegeneration

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Neural Regeneration Research 2023年第5期18卷 991-995页

作者： Diogo Trigo Jose joao Vitoria Odete A.b.da Cruz e Silva Neuroscience and Signalling Laboratory Institute of Biomedicine(iBiMED)Department of Medical SciencesUniversity of AveiroAveiroPortugal

In recent years, multiple disciplines have focused on mitochondrial biology and contributed to understanding its relevance towards adult-onset neurodegenerative disorders. These are complex dynamic organelles that have a variety of functions in ensuring cellular health and homeostasis. The plethora of mitochondrial functionalities confers them an intrinsic susceptibility to internal and external stressors(such as mutation accumulation or environmental toxins), particularly so in long-lived postmitotic cells such as neurons. Thus, it is reasonable to postulate an involvement of mitochondria in aging-associated neurological disorders, notably neurodegenerative pathologies including Alzheimer’s disease and Parkinson’s disease. On the other hand, biological effects resulting from neurodegeneration can in turn affect mitochondrial health and function, promoting a feedback loop further contributing to the progression of neuronal dysfunction and cellular death. This review examines state-of-the-art knowledge, focus on current research exploring mitochondrial health as a contributing factor to neuroregeneration, and the development of therapeutic approaches aimed at restoring mitochondrial homeostasis in a pathological setting.

关键词： Alzheimer’s disease axon energy homeostasis glymphatic system mitochondria mitostasis neurodegeneration neuroregeneration Parkinson’s disease therapeutical strategies

3D bioprinting-a model for skin aging

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Regenerative biomaterials 2023年第1期10卷 1212-1221页

作者： Ryeim b.Ansaf Rachel Ziebart Hemanth Gudapati Rafaela Mayumi Simoes Torigoe Stella Victorelli joao Passos Saranya P.Wyles Department of biology Colorado State University PuebloPuebloCO 81001USA Mayo Clinic Alix School of Medicine RochesterMN 55905USA Mayo Clinic Department of Dermatology RochesterMN 55905USA Mayo Clinic Graduate School of biomedical Sciences RochesterMN 55905USA Mayo Clinic Department of Physiology and biomedical Engineering RochesterMN 55905USA Mayo Clinic Robert and Arlene Kogod Center on Aging RochesterMN 55905USA

Human lifespan continues to extend as an unprecedented number of people reach their seventh and eighth decades of life,unveiling chronic conditions that affect the older ***-related skin conditions include senile purpura,seborrheic keratoses,pemphigus vulgaris,bullous pemphigoid,diabetic foot wounds and skin *** methods of drug testing prior to clinical trials require the use of pre-clinical animal models,which are often unable to adequately replicate human skin ***,a reliable model for aged human skin is *** current challenges in developing an aged human skin model include the intrinsic variability in skin architecture from person to *** ideal skin model would incorporate innate functionality such as sensation,vascularization and *** advent of 3D bioprinting allows us to create human skin equivalent for use as clinical-grade surgical graft,for drug testing and other *** this review,we describe the process of human skin aging and outline the steps to create an aged skin model with 3D bioprinting using skin cells(***,fibroblasts and melanocytes).We also provide an overview of current bioprinted skin models,associated limitations and direction for future research.

关键词： 3D bioprinting skin aging bioink regeneration

3D Progressive Damage based Macro-Mechanical FE Simulation of Machining Unidirectional FRP Composite

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 128-143页

作者： Yan-Li He joao-Paulo Davim Hong-Qian Xue Key Laboratory of Contemporary Design and Integrated Manufacturing Technology of Ministry of Education School of Mechanical EngineeringNorthwestern Polytechnical University Department of Mechanical Engineering University of AveiroCampus Santiago

Finite element(FE) simulation is a powerful tool for investigating the mechanism of machining fiber?reinforced polymer composite(FRP). However in existing FE machining simulation works,the two?dimensional(2 D) progressive damage models only describe material behavior in plane stress,while the three?dimensional(3 D) damage models always assume an instantaneous sti ness reduction pattern. So the chip formation mechanism of FRP under machin?ing is not fully analyzed in general stress state. A 3 D macro?mechanical based FE simulation model was developed for the machining of unidirectional glass fiber reinforced plastic. An energy based 3 D progressive damage model was proposed for damage evolution and continuous sti ness degradation. The damage model was implemented for the Hashin?type criterion and Maximum stress criterion. The influences of the failure criterion and fracture energy dissipa?tion on the simulation results were studied. The simulated chip shapes,cutting forces and sub?surface damages were verified by those obtained in the reference experiment. The simulation results also show consistency with previous 2 D FE models in the reference. The proposed research provides a model for simulating FRP material behavior and the machining process in 3 D stress state.

关键词： FRP Macro mechanical Machining Finite element Progressive damage

Combined penetrating keratoplasty, pars plana vitrectomy and Ahmed glaucoma valve implant after open globe injury： a challenging approach

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International Journal of Ophthalmology(English edition) 2017年第11期10卷 1786-1788页

作者： joao beato Antonio b.Melo Pedro A.Faria Luis Torrao Fernando Falcao-Reis Department of Ophthalmology Sao Joao Hospital CenterPorto 4200-319 Portugal Department of Sense Organs Faculty of Medicine University of Porto Porto 4200-319 Portugal

Dear Editor,I am ***？o beato,from the Ophthalmology Department of Sao Jo？o Hospital Center,Porto,Portugal.I write to present a case of combined penetrating keratoplasty（PKP）with temporary Eckardt keratoprosthesis,

关键词： OCULAR TRAUMA OUTCOMES

The Cauchy Problem for Coupled Nonlinear Schrdinger Equations with Linear Damping： Local and Global Existence and blowup of Solutions

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Chinese Annals of Mathematics,Series b 2016年第5期37卷 665-682页

作者： joao-Paulo DIAS Mario FIGUEIRA Vladimir V. KONOTOP LCMAF-CIO Faculdade de Ciencias Universidade de Lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal. Centro de Fisica Teorica e Computacional and Departamento de Fisica Faculdade de Ciencias Universidade de Lisboa Campo Grande Ed.C8 1749-016 Lisboa Portugal.

The authors study, by applying and extending the methods developed by Cazenave(2003), Dias and Figueira(2014), Dias et al.(2014), Glassey(1994–1997), Kato(1987), Ohta and Todorova(2009) and Tsutsumi(1984), the Cauchy problem for a damped coupled system of nonlinear Schrdinger equations and they obtain new results on the local and global existence of H^1-strong solutions and on their possible blowup in the supercritical case and in a special situation, in the critical or supercritical cases.

关键词： supercritical Cauchy applying estimates proof admissible constants uniqueness nonlinearity inequality