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Spin Number Coherent States and the Problem of Two Coupled Oscillators

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Communications in Theoretical Physics 2015年第7期64卷 34-38页

作者： d.Ojeda-Guillén r.d.mota V.d.Granados Escuela Superior de Fisica y Matemáticas Instituto Politécnico Nacional Ed. 9 Unidad Profesional Adolfo López Mateos Escuela Superior de Ingenieria Mecánica y Eléctrica Unidad Culhuacán Instituto Politécnico Nacional

From the definition of the standard Perelomov coherent states we introduce the Perelomov number coherent states for any su(2) Lie algebra. With the displacement operator we apply a similarity transformation to the su(2)generators and construct a new set of operators which also close the su(2) Lie algebra, being the Perelomov number coherent states the new basis for its unitary irreducible representation. We apply our results to obtain the energy spectrum, the eigenstates and the partition function of two coupled oscillators. We show that the eigenstates of two coupled oscillators are the SU(2) Perelomov number coherent states of the two-dimensional harmonic oscillator with an appropriate choice of the coherent state parameters.

关键词： coherent states Lie algebras coupled oscillators

Infuence of Process Parameters on the rF Sputtered GaP Thin Films

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Journal of Materials Science & Technology 2013年第9期29卷 821-829页

作者： d.A.mota G.Hema Chandra J.Ventura A.Guedes J.Pérez de la Cruz INESC TEC Rua do Campo Alegre n°687 IFIMUP-IN Rua do Campo Alegre n°687 Thin Film Laboratory Material Physics Division VIT University Geology department Faculty of Science University of Porto Rua do Campo Alegre n°687

In this work, gallium phosphide thin films were deposited on glass substrates by radio frequency （rF） magnetron sputtering technique under different depositions conditions. The X-ray diffraction analysis showed a diversity of states： from amorphous in the films deposited at 175 ~C to a nearly stoichiometric and polycrystalline films, exhibiting cubic phase with preferred orientation along （220）, in the films deposited at temperatures higher than 250 ~C. Scanning electron microscopy images revealed that all films were uniform with a smooth surface, while the energy-dispersive spectroscopy （EdS） analysis showed that there was a visible dependence on the Ga/P ratio in the deposition conditions and confirmed that a residual Ga metallic phase was presented in the surface of all the films. The raman analysis showed the structural evolution of the GaP films was strongly dependent on the deposition conditions. The conductivity of the films was slightly dependent on the argon pressure and the rf power, but strongly dependent on the deposition temperature, mainly above 200 ~C. The optical transmission and absorption analyses of the GaP films revealed an indirect band gap of ~ 1.70 eV in the films deposited at temperatures less than 200 ~C, which transited to a band gap of 2.26 eV as the deposition temperature was close to 300 ~C.

关键词： Gallium phosphide Thin films Sputtering Amorphous Band gap

Lignin engineering in forest trees: From gene discovery to field trials

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Plant Communications 2022年第6期3卷 1-25页

作者： Barbara de Meester ruben Vanholme Thatiane mota Wout Boerjan Ghent University Department of Plant Biotechnology and BioinformaticsTechnologiepark 719052 GhentBelgium VIB Center for Plant Systems Biology Technologiepark 719052 GhentBelgium

Wood is an abundant and renewable feedstock for the production of pulp,fuels,and biobased ***,wood is recalcitrant toward deconstruction into cellulose and simple sugars,mainly because of the presence of lignin,an aromatic polymer that shields cell-wall ***,numerous research efforts have focused on engineering lignin amount and composition to improve wood ***,we focus on results that have been obtained by engineering the lignin biosynthesis and branching pathways in forest trees to reduce cell-wall recalcitrance,including the introduction of exotic lignin *** addition,we draw general conclusions from over 20 years of field trial research with trees engineered to produce less or altered *** discuss possible causes and solutions for the yield penalty that is often associated with lignin engineering in ***,we discuss how conventional and new breeding strategies can be combined to develop elite clones with desired lignin *** conclude this review with priorities for the development of commercially relevant lignin-engineered trees.

关键词： lignin genetic engineering breeding CrISPr field trial forest trees

Quantum States of Interacting Atoms in Quasi-One-dimensional Ultracold Trapped Gases

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Journal of Modern Physics 2018年第3期9卷 443-460页

作者： Polyanna Guimaraes e Miranda débora Nazaréde Freitas AndréLuiz mota departamento de Ciências Naturais Universidade Federal de Sao Joao del-ReiSao Joao del-ReiBrazil Instituto Federal do Paraná Campus Assis Chateaubriand Assis ChateaubriandBrazil

We theoretically investigate the quantum states of a Hamiltonian model for quasi-one-dimensional ultracold trapped gases. From the ansatz given by the numerical solution of the Schrödinger equation of the system, we develop a scattering potential functional form and an approximate solution for the analytical approach of the model. We obtain the set of approximate eigenstates and eigenenergies that can be used in future improvements on the study of atomic scattering in low dimensional ultracold gases. We also show that there is a parity inversion of the ground state of the model as the interaction strength increases.

关键词： Ultracold Trapped Gases Confined Eigenstates resonance

Posterior corneal astigmatism modifications after cataract surgery and its role on total corneal astigmatism

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Annals of Eye Science 2018年第1期3卷 267-275页

作者： diana Silva Mafalda mota Catarina Pedrosa Peter Pêgo Sara Pinto Cristina Vendrell Isabel Prieto Ophthalmology department Hospital Prof.Dr.Fernando Fonseca E.P.E.AmadoraPortugal

Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total *** study aims to ascertain if there is significant change in the posterior corneal astigmatism after cataract surgery and its impact on the total ***:Analysis of 76 eyes that underwent cataract surgery with monofocal intraocular lens *** topography was performed with Pentacam(OCULUS®)pre-and *** corneal astigmatism was calculated with the algorithm of vergence *** compared preoperative and postoperative changes in the magnitude and axis differences of anterior corneal curvature astigmatism,posterior corneal curvature astigmatism and the calculated total corneal *** calculated the correlation between the total preoperative astigmatism and the difference between total corneal astigmatism and anterior corneal ***:The mean preoperative and postoperative posterior astigmatism was 0.31±0.02 d,showing no significant differences before and after surgery(P=0.989).Statistically significant differences between the calculated total corneal astigmatism and anterior corneal astigmatism were registered preoperatively and postoperatively in the with-the-rule anterior(WTr)corneal astigmatism(P=0.004,Prule(ATr)anterior corneal astigmatism(Pd in the oblique(P=0.026,P=0.019)*** posterior corneal astigmatism and the total corneal astigmatism correlated positively with the differences between the total corneal and anterior corneal astigmatism(r=0.378,P=0.001).Conclusions:There were statistically significant differences between the magnitude of the total astigmatism and anterior corneal astigmatism,underlining the impact of posterior corneal astigmatism.A positive correlation between the preoperative posterior astigmatism and the difference between the total corneal and the ant

关键词： Astigmatism cataract surgery intraocular lens posterior corneal curvature total corneal astigmatism

Physiological plasticity in eucalyptus clones in the vegetative stage contributes to drought tolerance

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Journal of Forestry research 2023年第5期34卷 1549-1561页

作者： Vilma Marques Ferreira Jailma ribeiro de Andrade Claudiana Moura dos Santos Sebastiao de Oliveira Maia Júnior Joao Correia de Araújo Neto Andrea Francisca da Silva Santos Vicente mota da Silva Lucas Teles Bezerra Laurício Endres Laboratório de Fisiologia Vegetal Campus de Engenharia e Ciências AgráriasUniversidade Federal de AlagoasRio LargoAL57072-900Brazil Laboratório de Ciências Ambientais e Biodiversidade Departamento de Zootecnia.Centro de Ciências AgráriasUniversidade Estadual do MaranhãoSão LuísMA65300-000Brazil Laboratório de Propagação de Plantas.Campus de Engenharia e Ciências Agrárias Universidade Federal de AlagoasRio LargoAL57072-900Brazil Laboratório de Lepidoptera Museu de ZoologiaUniversidade de São PauloIpirangaSão PauloSP04263-000Brazil

With the expansion of eucalyptus crops to areas with severe water limitations,physiological studies involving eucalyptus clones to identify those that are tolerant to water stress become *** objective of this study was to assess morphological and physiological responses by eucalyptus clones subjected to drought stress and *** experiment consisted of three eucalyptus clones:VC865,I224 and I144 and two water regimes:control and water stress followed by rehydration,with six *** water potential,gas exchange,maximum quantum efficiency of photo systemⅡand plant height and stem diameter were evaluated under drought stress and ***6 d of rehydration,the number of leaves,leaf area and dry mass of root,leaf,stem and their total were *** clones showed intense reduction of gas exchange during the drought stress period,and only VC865 and 1144 showed rapid recovery with 3 d of *** 1224 showed greater reduction in height,stem diameter,number of leaves,water potential at midday(Ψ_(w)_(Midday)),and maximum quantum efficiency of photosystemⅡ(F_(v)/F_(m)).Clones VC865and T144 showed lower reductions inΨ_(wMidday)and F_(v)/F_(m) under ***865 had lower reductions in leaf number,leaf area and higher leaf dry mass,while clone I144 had higher height and lower reduction in root dry mass *** these clones showed higher water use efficiency with 3d of *** different phenotypic plasticities gave the clones VC865 and 1144 efficient mechanisms of acclimatization to stress and more drought tolerance,enhancing their greater capacity for recovery after stress,which allowed lower dry mass *** 1224,however,was more susceptible to drought stress,undergoing greater physiological damage with only partial recovery during rehydration.

关键词： drought Eucalyptus species Gas exchanges Post-stress root dry mass

A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications

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Bio-design and Manufacturing 2024年第3期7卷 277-291页

作者： I.A.O.Beeren G.dos Santos P.J.dijkstra C.mota J.Bauer H.Ferreira rui L.reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni department of Complex Tissue regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory 4806-909 Braga/GuimarãesPortugal POLYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain IKErBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering ***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell *** of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different *** porous three-dimensional(3d)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL *** a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was *** two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPrII)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human

3d Printing Technology for Tapered Optical Fiber Protection With Gas Sensing Possibilities

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Photonic Sensors 2020年第4期10卷 298-305页

作者： Kaleb roncatti de SOUZA Jonas H.OSÓrIO Juliana B.CArVALHO Beatriz mota LIMA Cristiano M.B.COrdEIrO Gleb Wataghin Physics Institute State University of CampinasCampinas 13083-970Brazil

We present a new procedure for protecting micro-optical fibers(tapered fibers)by using the 3-dimensional(3d)printing technology.A standard single-mode optical fiber was tapered down to the diameter of 1mm and embedded in a polymeric matrix obtained by an additive manufacturing *** show that the proposed structure protects the fiber taper against environmental humidity while keeping permeability to gas flow and the possibility of the realization of gas detection *** our knowledge,this is the first time 3d printed casings were applied to protect fiber tapers from humidity *** envisage this new approach will allow the development of new fiber taper devices to better resist in humid environments.

关键词： 3d printing additive manufacturing optical fiber tapered fibers sensing

3d additive manufactured composite scaffolds with antibiotic-loaded lamellar fillers for bone infection prevention and tissue regeneration

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Bioactive Materials 2021年第4期6卷 1073-1082页

作者： María C´amara-Torres Stacy duarte ravi Sinha Ainhoa Egizabal Noelia´Alvarez Maria Bastianini Michele Sisani Paolo Scopece Marco Scatto Alessandro Bonetto Antonio Marcomini Alberto Sanchez Alessandro Patelli Carlos mota Lorenzo Moroni Maastricht University MERLN Institute for Technology-Inspired Regenerative MedicineComplex Tissue Regeneration DepartmentUniversiteitssingel 406229ERMaastrichtthe Netherlands TECNALIA Basque Research and Technology Alliance(BRTA)Mikeletegi Pasealekua 220009Donostia-San SebastianSpain Prolabin&Tefarm S.r.l. Via Dell’Acciaio906134PerugiaItaly d Nadir S.r.l.Via Torino155/b30172VeniceItaly department of Environmental Sciences Informatics and StatisticsCa’Foscari University of VeniceDorsoduro 324630172VeniceItaly department of Physics and Astronomy Padova UniversityVia Marzolo835131PadovaItaly

Bone infections following open bone fracture or implant surgery remain a challenge in the orthopedics *** order to avoid high doses of systemic drug administration,optimized local antibiotic release from scaffolds is required.3d additive manufactured(AM)scaffolds made with biodegradable polymers are ideal to support bone healing in non-union scenarios and can be given antimicrobial properties by the incorporation of *** this study,ciprofloxacin and gentamicin intercalated in the interlamellar spaces of magnesium aluminum layered double hydroxides(MgAl)andα-zirconium phosphates(ZrP),respectively,are dispersed within a thermoplastic polymer by melt compounding and subsequently processed via high temperature melt extrusion AM(~190◦C)into 3d *** inorganic fillers enable a sustained antibiotics release through the polymer matrix,controlled by antibiotics counterions exchange or pH ***,both antibiotics retain their functionality after the manufacturing process at high temperatures,as verified by their activity against both Gram+and Gram-bacterial ***,scaffolds loaded with filler-antibiotic do not impair human mesenchymal stromal cells osteogenic differentiation,allowing matrix mineralization and the expression of relevant osteogenic ***,these results suggest the possibility of fabricating dual functionality 3d scaffolds via high temperature melt extrusion for bone regeneration and infection prevention.

关键词： Melt extrusion additive manufacturing Antibiotic delivery Lamellar inorganic fillers Bone infection Bone regeneration Human mesenchymal stromal cells