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Frontiers of Materials Science 2011年第2期5卷 126-134页

作者： j.a-Lin GUO p. Le MASSON E. ARTIOUKHINE T. LOULOU P. ROGEON M. CARIN M. DUMONS j. costa Department of Materials Engineering School of Power and Mechanical Engineering Wuhan University Wuhan 430072 China LET2E/ETM Laboratoire d＇Etudes Thermique Energetique et Environnement Equipe Thermophysique et Materiaux Universite de Bretagne Sud C.U.R.S.T. F-56321 Lorient Cedex France Institut FEMTO-ST Departement CREST CNRS Belfort France

In previous work, we have analyzed the feasibility of the estimation for a source term S（x, y, z） in a transversal section, The present study is concerned with a twodimensional inverse phase change problem. The goal is the estimation of the dissipated heat flux in the liquid zone （reconstruction of a source term in the energy equation） from experimentally measured temperatures in the solid zone. This work has an application in the electron beam welding of steels of thickness about 8cm. The direct thermometallurgical problem is treated in a quasi steady two-dimensional longitudinal section （x, y）. The beam displacement is normally in the y direction. But in the quasi steady simulation, the beam is steady in the study section. The sample is divided in the axial direction z in few sections. At each section, a source term is defined with a part of the beam and creates a vaporized zone and a fused zone. The goal of this work is the rebuilding of the complete source term with the estimations at each section. In this paper, we analyze the feasibility of the estimation. For this work, we use only the simulated measurements without noise.

关键词： estimation source term quasi steady the iterative regularization method

Lagged Coherence of Photon Emissions and Spectral Power Densities between the Cerebral Hemispheres of Human Subj.cts during Rest Conditions: Phase Shift and Quantum Possibilities

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World j.urnal of Neuroscience 2016年第2期6卷 119-125页

作者： j. N. costa B. T. Dotta M. A. Persinger Behavioural Neuroscience Program Laurentian University Sudbury Canada Biology Department Laurentian University Sudbury Canada Psychology Department Laurentian University Sudbury Canada Biomolecular Sciences Program Laurentian University Sudbury Canada

Photon counts about 15 cm from the left and right sides of the head while subj.cts sat quietly during baseline conditions within a hyper-dark chamber were measured by photomultiplier units. Lag/lead analyses for photon emissions between the two hemispheres indicated a weak but statistically significant correlation between the amplitude fluctuations that were separated by about 800 to 900 ms. Analyses of the spectral power densities of photon amplitude variations from the left and right hemispheres revealed peak values between 2 and 3 Hz which were equivalent to a difference of about 900 ms. The radiant flux densities were estimated to be in the order of 10?12 W?m?2 and to include the equivalence of about 107 neurons. Our calculations, which accounted for the small magnitude of the strength of the interhemispheric coefficients, suggest that the coherence could be strongly correlated with processes associated with the unmyelinated axons with diameters between 400 to 800 nm, the visible wavelengths, within the corpus callosum. When the ratio of the phase shift was applied to the Aharanov-Bohm equation, the time required for a photon-related electron to be within a cerebral magnetic field was the same duration as a single orbit of an electron and a photon’s traversal latency across a neuronal plasma membrane. We suggest that the peak photon decoherence between the two cerebral hemispheres may reveal a neuronal-quanta substrate to the conditions associated with consciousness.

关键词： Biophotons Interhemispheric Correlations Imagination Human Brain Quantitative EEG (QEEG) Visualization Corpus Callosum Aharanov-Bohm Effect

Kinetic Characterization of Na,K-ATPase Inhibition by the Acetaminophen Metabolite N-Acetylbenzoquinoneimine

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Open j.urnal of Molecular and Integrative Physiology 2015年第1期5卷 1-17页

作者： j.ff B. Helms Lauren P. Saunders j.mie Meyer Charles j. costa Eric Plowman Nick Williford Matthew Corbitt j.remy P. Holden Craig Gatto Department of Biology Upper Iowa University Fayette IA USA Division of Neuroscience and Physiology Department of Biological Science Illinois State University Normal IL USA Department of Internal Medicine University of Wisconsin-Madison Medical Center Madison WI USA

N-acetylbenzoquinoneimine (NABQI) is a toxic metabolite of the common analgesic acetaminophen (APAP). NABQI is an electrophilic intermediate formed via the oxidation of APAP within the cytochrome P450 system. Within the normally recommended low-dose use of APAP, NABQI is a minor metabolite which is either quickly reduced back to APAP or conj.gated to Glutathione (GSH) producing an innocuous by-product. However, with overdose or prolonged high-dose usage of acetaminophen, GSH levels can become depleted and the bioactive NABQI is thought to form adducts with proteins and oxidize protein sulfhydryls producing intra- and intermolecular disulfide bridges in proteins. In this work we investigated the effect of NABQI on purified kidney Na,K-ATPase to see if the clinical renal insufficiencies seen in APAP overdose may be linked to inhibition of the Na,K-ATPase. Our work has shown that NABQI does indeed inhibit the Na,K-ATPase in a dose dependent (IC50 = 19.8 ± 2.9 μM) and irreversible manner. Interestingly, brief storage of NABQI at -20°C eliminates the irreversible effects of the compound, and leads to a product that remains a potent reversible inhibitor of the Na,K-ATPase (IC50 = 58.7 ± 19.5 μM). Further, the reversible inhibition produced by stored NABQI competes with para-nitrop.

关键词： Na K-ATPase Paracetamol N-Acetylbenzoquinoneimine Overdose Renal Electrophillic

Idiopathic gastric partial necrosis

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Open j.urnal of Gastroenterology 2013年第7期3卷 314-316页

作者： Rocío González López M. Muinelo Lorenzo j. Pérez Grobas L. Muínos Ruano L. Ramírez Ruíz A. Mohammed Salem M. Rodríguez González j. A. costa Buj.n Department of General Surgery and Digestive Diseases Lucus Augusti University Hospital Lugo Spain

We present the case of an elderly patient, who had orthopaedic surgery and suffered in the early post-operative period an idiopathic gastric partial necrosis. We reviewed the literature and it is an extraordinarily infrequent entity. Partial resections have already been described in case of limited necrosis, as reported in our case. Prompt diagnosis of idiopathic gastric necrosis and aggressive treatment are mandatory. Further awareness of this strange entity and its risk factors can lead to a quicker diagnosis and higher possibilities of survival for the patient.

关键词： Gastric Necrosis Orthopedic Surgery

Nucleon Finite Volume Effect and Nuclear Matter Properties in a Relativistic Mean-Field Theory

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Communications in Theoretical Physics 2006年第6X期46卷 1052-1058页

作者： R. costa A.j. Santiago H. Rodrigues j. Sa Borges Instituto de Fisica Universidade do Estado do Rio de Janeiro Rio de Janeiro-RJ 20559-900 Brazil Centro Federal de Educ~ao Tecnológica Rio de j.neiro Brazil

Effects of excluded volume of nucleons on nuclear matter are studied, and the nuclear properties that follow from different relativistic mean-field model parametrizations are compared. We show that, for all tested parametrizations, the resulting volume energy al and the symmetry energy j.are around the acceptable values of 16 MeV and 30 MeV, and the density symmetry L is around 100 MeV. On the other hand, models that consider only linear terms lead to incompressibility Ko much higher than expected. For most parameter sets there exists a critical point （pc, δc）, where the minimum and the maximum of the equation of state are coincident and the incompressibility equals zero. This critical point depends on the excluded volume parameter r. If this parameter is larger than 0.5 fm, there is no critical point and the pure neutron matter is predicted to be bound. The maximum value for neutron star mass is 1.85M⊙, which is in agreement with the mass of the heaviest observed neutron star 4U0900-40 and corresponds to r = 0.72 fm. We also show that the light neutron star mass （1.2M⊙） is obtained for r ≌ 0.9 fro.

关键词： nuclear matter relativistic models nuclear matter aspects of neutron stars

Tailored surface textures to increase friction-A review

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Friction 2022年第9期10卷 1285-1304页

作者： Henara L.costa j.rg SCHILLE Andreas ROSENKRANZ School of Engineering Surface Engineering GroupUniversidade Federal do Rio GrandeRio Grande 96203900Brazil University of Applied Sciences Mittweida Laserinstitut Hochschule Mittweida 09648Germany Department of Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiago 8370459Chile

Surface textures with micro-scale feature dimensions still hold great potential to enhance the frictional performance of tribological *** from the ability of surface texturing to reduce friction,surface textures can also be used to intentionally increase friction in various applications that rely on friction for their adequate ***,this review aims at presenting the state-of-the-art regarding textured surfaces for high-friction *** a brief general introduction,the recent trends and future paths in laser surface texturing are ***,the potential of surface textures to increase friction in different applications including adhesion,movement transmission and control,biomimetic applications,and road-tire contacts is critically *** emphasis in this section is laid on the involved mechanisms responsible for friction ***,current short-comings and future research directions are pointed out thus emphasizing the great potential of(laser-based)surface texturing methods for innovations in modern surface engineering.

关键词： surface texturing tribology laser processing friction increase

Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 921-935页

作者： A.Colaço P.Alves costa C.Ferreira C.Parente j.Fernandez-Ruiz CONSTRUCT-FEUP University of PortoRua Dr.Roberto Frias4200-465 PortoPortugal University of La Coruña Department of Civil EngineeringCampus de Elviña 15071La CoruñaSpain

Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the *** pile driving is an interesting and viable solution from economic and technical points of ***,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately *** this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear *** the complexity of the problem,an experimental test site was developed and fully *** experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile *** comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile *** experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models.

关键词： pile driving ground-borne vibrations numerical modeling experimental validation

Soil Formation of "Atlantic Rankers" from NW Spain—A High Resolution Aluminium and Iron Fractionation Study

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Pedosphere 2008年第4期18卷 441-453页

作者： j. KAAL M. costa-CASAIS C. FERRO-VZQUEZ X. PONTEVEDRA-POMBAL A. MARTINEZ-CORTIZAS Instituto de Estudios Galegos Padre Sarmiento Laboratorio de Arqueología del Paisaje (LAr) IEGPS-CSIC-XuGaRúa San Roque 2 15704 Santiago de Compostela (Spain). Departamento de Edafología y Química Agrícola Fac. Biología Universidad de Santiago (Spain)

Atlantic rankers belong to the group of ＂cryptopodzolic rankers＂, which are ubiquitous in the mountainous cool/temperate humid regions of Western Europe. The rankers of Galicia （NW Spain） formed by thousands of years of colluviation. The preponderance of Al-stabilised organic matter （OM） masks the horizonation and polycyclic character （i.e., stratification） of these soils. Cryptopodzolic rankers are generally thought to be the outcome of podzolisation. This soil type is part of the recent discussion on how to classify soils developed from nonvolcanic parent material having andic properties. To better understand the formation processes of these soils, the Al and Fe fractionation of four typical Atlantic rankers were studied by selective dissolution in acid NH4-oxalate, Na-pyrophosphate and the chlorides of K, La and Cu. A high-resolution sampling approach allowed us to investigate the soils in greater detail than simply sampling by horizon. The rankers studied display a distribution of Fe- and AI-OM complexes that is typical of cryptopodzolic soils. However, these organomineral associations were probably immobile due to the high Al saturation. We argue that the soils owe their characteristic chemical status to external factors rather than to translocation of organomineral associations： variations in AI-OM concentrations could be linked to changes in weathering/leaching intensity and colluviation rates caused by anthropogenic disturbances or changes in regional climate regime.

关键词： Al fractionation colluviation cryptopodzolic soil podzolisation ranker

Functionalization of AuMSS nanorods towards more effective cancer therapies

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Nano Research 2019年第4期12卷 719-732页

作者： Carolina F. Rodrigues Telma A. j.cinto Andre F. Moreira Elisabete C. costa Sonia P. Miguel Ilidio j. Correia CICS-UBI -Centro de Investigagao em Ciencias da Saude Universidade da Beira Interior Covilhd 6200-506 Portugal CIEPQF - Departamento de Engenharia Quimica Universidade de Coimbra Rua 13 Silvio Lima Coimbra 3030-790 Portugal

The applicatio n of nano particles as selective drug delivery platforms arises as one the most promising therapeutic strategies in the biomedical field. Such systems can encapsulate drugs, prevent its premature degradation, transport and promote the drugs specific delivery to the target site. Among the different nanostructures, gold-core mesoporous silica shell (AuMSS) nanorods have been one of the most explored due to their unique physical and chemical properties. The mesoporous silica biocompatibility, high surface area that can be easily functionalized, tubular pores that can store the drugs, conj.gated with the intrinsic capacity of gold nanorod to absorb near-infrared radiation, allows the combination of hyperthermia (i.e., photothermal effect) with drug delivery, making them a nanoplatforms with a huge potential for cancer therapy. Nevertheless, the successful applicati on of AuMSS nanoparticles as an effective can cer nano medicine is hindered by the uncon trolled release of the therapeutic payloads, limited blood circulation time and unfavorable pharmacokinetics. In this review, an overview of the modificati ons performed to improve the AuMSS nano rods applicati on in nanom edicine is provided, highlighting the practical approaches that enhaneed the AuMSS nanorods targeting, responsiveness to different stimuli, and blood circulation time. Further, the basics of AuMSS nano rods syn thesis procedures, gen eral properties, and its applicati on in can cer therapy are also described.

关键词： gold nano rods silica surface modifications targeting cancer

Broadband Optical Active Waveguides Written by Femtosecond Laser Pulses in Lithium Fluoride

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Chinese Physics Letters 2014年第1期31卷 72-75页

作者： Ismael Chiamenti Francesca Bonfigli Anderson S. L. Gomes Rosa Maria Montereali Larissa N. da costa Hypolito j. Kalinowski Federal University of Technology- Parang 80230-901 Curitiba Brazil ENEA C. R. Frascati Photonics Micro and Nanostructures Laboratory UTAPRAD-MNF V. E. Fermi 45 00044 Frascati (Rome) Italy Department of Physics Universidade Federai de Pernambuco necife Brazil

Broadband waveguiding through light-emitting strips directly written in a blank lithium fluoride crystal with a femtosecond laser is reported. Light guiding was observed at several optical wavelengths, from blue, 458 nm, to near-infrared, at 155nm. Visible photoluminescence spectra of the optically active F2 and F33 color centers produced by the fs laser writing process were measured. The wavelength-dependent refractive index increase was estimated to be in the order of 10-3-10-4 in the visible and near-infrared spectral intervals, which is consistent with the stable formation of point defects in LiF.

关键词： POINT defects CRYSTAL defects IMPURITY centers ANTISITE defects INTERSTITIALS FLUX pinning