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Deep optics preconditioner for modulation-free pyramid wavefront sensing

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Photonics Research 2024年第2期12卷 301-312页

作者： FELIPE guzm.n JORGE TAPIA CAmILO WEInBERGER nICOLÁS hernÁndez JORGE BACCA BEnOIT nEICHEL ESTEBAn VERA School of Electrical Engineering Pontificia Universidad Católica de Valparaı´soValparaı´soChile Department of Systems Engineering Universidad Industrial de SantanderBucaramangaColombia Laboratoire d’Astrophysique de marseille MarseilleFrance

The pyramid wavefront sensor(PWFS)can provide the sensitivity needed for demanding adaptive optics applications,such as imaging exoplanets using the future extremely large telescopes of over 30 m of diameter(D).However,its exquisite sensitivity has a limited linear range of operation,or dynamic range,although it can be extended through the use of beam modulation—despite sacrificing sensitivity and requiring additional optical *** by artificial intelligence techniques,this work proposes to train an optical layer—comprising a passive diffractive element placed at a conjugated Fourier plane of the pyramid prism—to boost the linear response of the pyramid sensor without the need for cumbersome *** develop an end-2-end simulation to train the diffractive element,which acts as an optical preconditioner to the traditional least-square modal phase estimation *** results with a large range of turbulence conditions show a noticeable improvement in the aberration estimation performance equivalent to over 3λ∕D of modulation when using the optically preconditioned deep PWFS(DPWFS).Experimental results validate the advantages of using the designed optical layer,where the DPWFS can pair the performance of a traditional PWFS with 2λ∕D of *** and adding an optical preconditioner to the PWFS is just the tip of the iceberg,since the proposed deep optics methodology can be used for the design of a completely new generation of wavefront sensors that can better fit the demands of sophisticated adaptive optics applications such as ground-to-space and underwater optical communications and imaging through scattering media.

关键词： process optics pyramid

model based current mode control design and experimental validation for a 3φ rectifier under unbalanced grid voltage conditions

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Journal of modern Power Systems and Clean Energy 2018年第4期6卷 777-790页

作者： P.R.mARTínEZ-RODRIGEZ Jose m.SOSA Samuel ITURRIAGA-mEDInA Gerardo ESCOBAR Gerardo VáZQUEZ-guzm.n Andres A.VALDEZ-FERnández School of Sciencies UASLP Laboratory of Electrical and Power Electronics ITESI School of Engineering Universidad Modelo

This paper addresses the control design and the experimental validation of a current mode control for a three phase voltage source rectifier. The proposed control law is able to fulfill the voltage regulation and the current tracking control objectives despite of unbalanced and distorted grid voltages. The proposed control law consists of two loops, which are referred as inner tracking loop and the outer voltage regulation loop. The inner loop is designed to provide damping to the system, which also includes and adaptive mechanism. The construction of the current reference is based on the positive component detection of thegrid voltage. Therefore, the current produced by the power rectifier is proportional to the fundamental component of the grid voltage, despite of the presence of unbalanced grid voltages. The voltage regulation loop is designed as a proportional-integral controller, which is aimed to regulate the DC output voltage to a desired level. Finally, experimental results are obtained in an experimental prototype of2 kW to evaluate the performance of the proposed controller.

关键词： Pulse-width modulation rectifier Power factor correction Positive-component Current mode control

methanogenesis and methanotrophy in Soil: A Review

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Pedosphere 2014年第3期24卷 291-307页

作者： n.SERRAnO-SILVA Y.SARRIA-guzm.n L.DEnDOOVEn m.LUnA-GUIDO Laboratory of Soil Ecology ABACUS Cinvestav Instituto Politecnico Nacional 2508 C.P.07360 mexico d.f.(mexico)

Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenhouse gases （GHG） concentration. Water vapor, carbon dioxide （CO2）, methane （CH4） and nitrous oxide （n20） are the most important GHG, and human activities, such as industry, livestock and agriculture, contribute to the production of these gases. methane, at an atmospheric concentration of 1.7 gmol tool-1 currently, is responsible for 16% of the global warming due to its relatively high global warming potential. Soils play an important role in the CH4 cycle as methanotrophy （oxidation of CH4） and methanogenesis （production of CH4） take place in them. Understanding methanogenesis and methanotrophy is essential to establish new agriculture techniques and industrial processes that contribute to a better balance of GHG. The current knowledge of methanogenesis and methanotrophy in soils, anaerobic CH4 oxidation and methanotrophy in extreme environments is also discussed.

关键词： anaerobic CH4 oxidation biological production global warming methanogenic archaea methanotrophic bacteria

Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang Arturo J.hernndez-maldonado Zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/m^(n+)-zeolite X(Si/Al=1,m^(n+)=Cu^(2+) and ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor m^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and m^(n+)-zeolite X, and their interactions with m^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on m^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern Zeolite X

Trivial and Simple Spectrum for SL(d,R) Cocycles with Free Base and Fiber Dynamics

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Acta mathematica Sinica,English Series 2015年第7期31卷 1113-1122页

作者： m.rio BESSA Paulo VARAnDAS Departamento de matemtica Universidade da Beira InteriorRua Marquês d'vila e Bolama6201-001 CovilhPortugal Departamento de matemtica Universidade Federal da BahiaAv.Ademar de Barros s/n40170-110 SalvadorBrazil

Let ACD（m, SL（d,R）） denote the pairs （f, A） so that f∈ A C Diff^1（m） is a C^1-Anosov transitive diffeomorphisms and A is an SL（d,R） cocycle dominated with respect to f. We prove that open and densely in ACD（m, SL（d,R））, in appropriate topologies, the pair （f,A） has simple spectrum with respect to the unique maximal entropy measure μf. Then, we prove prevalence of trivial spectrum near the dynamical cocycle of an area-preserving map and also for generic cocycles in AUtLeb（m） × LP（m, SL（d, R））.

关键词： Linear cocycles Lyapunov exponents Anosov diffeomorphisms topological conjugacy,maximal entropy measures

Spatial variability of soil organic carbon stock in an olive orchard at catchment scale in Southern Spain

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International Soil and Water Conservation Research 2023年第2期11卷 311-326页

作者： Jose A.Gòmez Gema guzm.n Tom Vanwalleghem Karl Vanderlinden Institute for Sustainable Agriculture.Spanish national Research Council(IAS-CSIC) Alameda del Obispo S/N14004CordobaSpain Department of Agronomy University of CordobaCampus de Rabanales14071CordobaSpain Centro IFAPA Alameda del Obispo 14004CordobaSpain

Orchards have a high potential for carbon ***,little research is available on the spatial variability at catchment scale and on the difference between the tree area and the *** analyzed theik spatial variability of soil organic carbon stock,SOCstock at 90 cm depth in an 8-ha catchment in Southern Spain with olives on a vertic *** showed higher soil organic carbon concentration,SOC,in the tree area as compared to the lane up to 60 cm depth,but its impact on SOCstock was negligible since it was compensated by the higher soil bulk density in the *** at different depths was correlated with that in the top 0-5 *** overall SOCstock of the orchard was 4.14 kg m^(-2),ranging between 1.8 and 6.0 kg m^(-2).This SOCstock is in the mid-lower range of values reported for olive orchards,measured at smaller scale,and similar to those other intensive field crops and agroforestry under comparable rainfall *** spatial variability in SOCstock was correlated to several geomorphological variables:elevation,cumulative upstream area,topographic wetness index,sediment transport index,and tillage *** in SOC and SOCstock are driven by the sediment redis-tribution downslope,mainly by tillage erosion,and higher soil water availability in lower areas allowing higher biomass *** topographic indexes and the correlation between SOC in the topsoil and SOCstock up to 90 cm should be further explored in other typology of olive orchards for facilitating the mapping of SOC_(stock).

关键词： Carbon sequestration mediterraneancrops Catchment Spatial variability Vertic soils

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： Luis Delaye Graciela García-guzm.n martin Heil Departamento de Ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico Departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of ***,many of them contribute to the resistance phenotype of their ***,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic *** analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRnA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic *** character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined *** contrast,biotrophs formed five clusters that did not contain necrotrophs or *** biotrophy evolves there is apparently no regression to one of the other two *** conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological *** experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects

The combination of a microbial and a non-microbial biostimulant increases yield in lettuce(Lactuca sativa) under salt stress conditions by up-regulating cytokinin biosynthesis

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Journal of Integrative Plant Biology 2024年第10期66卷 2140-2157页

作者： Patricia Benito marina Celdrán Javier Bellón Vicente Arbona miguel González-guzm.n Rosa Porcel Lynne Yenush José m.mulet Instituto de Biología molecular y Celular de Plantas(IBmCP) Universitat Politècnica de València-Consejo Superior de Investigaciones CientíficasValencia 46022Spain Caldic Ibérica S.L.Barcelona 08210Spain Department of Biología Bioquímica y Ciencias NaturalesUniversitat Jaume ICampus Riu SecE-Castellón 12071Spain

Salinization poses a significant challenge in agriculture, exacerbated by anthropogenic global warming. Biostimulants, derived from living microorganisms or natural extracts, have emerged as valuable tools for conventional and organic ***, our understanding of the molecular mechanisms underlying the effects of biostimulants is very limited, especially in crops under real cultivation conditions. In this study, we adopted an integrative approach to investigate the effectiveness of the combined application of plant growth-promoting bacterium(Bacillus megaterium strain Bm08) and a non-microbial biostimulant under control conditions(normal watering) and salt stress. After confirming the yield increase under both conditions, we investigated the molecular mechanisms underlying the observed effect by measuring a number of physiological parameters(i.e., lipid peroxidation, antioxidants,chlorophylls, total phenolics and phytohormone content), as well as RnA sequencing and primary metabolite analyses. Our findings reveal that the combined effect of the microbial and non-microbial biostimulants led to a decrease in the antioxidant response and an up-regulation of genes involved in cytokinin biosynthesis under salt stress ***, in turn, resulted in a higher concentration of the bioactive cytokinin, isopentenyladenosine, in roots and leaves and an increase in γ-aminobutyric acid, a non-proteic amino acid related to abiotic stress responses. In addition, we observed a decrease in malic acid, along with an abscisic acid(ABA)-independent up-regulation of SR-kinases, a family of protein kinases associated with abiotic stress responses. Furthermore, we observed that the single application of the non-microbial biostimulant triggers an ABA-dependent response under salt stress;however, when combined with the microbial biostimulant, it potentiated the mechanisms triggered by the Bm08 bacterial strain. This comprehensive investigation shows that the combination o

关键词： abscisic acid biostimulants cytokinins isopentenyl adenosine lettuce salt stress

Immunomodulatory biomaterial-based wound dressings advance the healing of chronic wounds via regulating macrophage behavior

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Regenerative Biomaterials 2022年第1期9卷 1131-1142页

作者： Ana Beatriz Sousa Artur P.Águas m.rio A.Barbosa Judite n.Barbosa i3S—Instituto de Inovaçäo e Investigaçäo em Saúde Universidade do PortoRua Alfredo Allen2084200-125 PortoPortugal InEB—Instituto de Engenharia Biomédica Rua Alfredo Allen2084200-125 PortoPortugal ICBAS—Instituto de Ciências Biomédicas Abel Salazar Universidade do PortoRua de Jorge Viterbo Ferreira2284050-313 PortoPortugal UmIB—Unit for multidisciplinary Biomedical Research of ICBAS—Instituto de Ciências Biomédicas de Abel Salazar Universidade do PortoRua de Jorge Viterbo Ferreira2284050-313 PortoPortugal

Successful wound healing is a process that has three overlying phases:inflammatory,proliferative and *** wounds are characterized by a perpetuated inflammation that inhibits the proliferative and remodeling phases and impairs the wound *** are key modulators of the wound healing ***,they are responsible for the wound cleaning and for the phagocytosis of pathogens and afterwards they lead to the resolution of the inflammatory response and they express growth factors important for angiogenesis and cytokines and growth factors needed for cell proliferation and deposition of extracellular *** phenotype of the macrophage changes gradually throughout the healing process from the initial m1 pro-inflammatory phenotype characteristic of the acute response to the m2 pro-regenerative phenotype that allows an accurate tissue *** chronic wounds,m1 pro-inflammatory macrophages persist and impair tissue *** such,immunomodulatory biomaterials arise as promising solutions to accelerate the wound healing *** this review,we discuss the importance of macrophages and their polarization throughout the different phases of wound healing;macrophage dysfunction in chronic wounds and the use of immunomodulatory biomaterials to overcome the critical problem of chronic wounds-the continued inflammatory phase that impairs healing.

关键词： wound healing chronic wounds macrophage immunomodulatory biomaterials