Photosynthesis is a fundamental process in biosciences and biotechnology that influences profoundly the research in other disciplines.In this paper,we focus on the characterization of fundamental components,present in...Photosynthesis is a fundamental process in biosciences and biotechnology that influences profoundly the research in other disciplines.In this paper,we focus on the characterization of fundamental components,present in pigment-protein complexes,in terms of their spectroscopic properties such as infrared spectra,nuclear magnetic resonance,as well as nuclear quadrupole resonance,which are of critical importance for many applications.Such components include chlorophylls and bacteriochlorophylls.Based on the density functional theory method,we calculate the main spectroscopic characteristics of these components for the Fenna-Matthews-Olson light-harvesting complex,analyze them and compare them with available experimental results.Future outlook is discussed in the context of current and potential applications of the presented results.展开更多
Alzheimer’s disease(AD)is a common neurodegenerative disorder nowadays.Amyloid-beta(Aβ)and tau proteins are among the main contributors to the AD progression.In AD,Aβproteins clump together to form plaques and disr...Alzheimer’s disease(AD)is a common neurodegenerative disorder nowadays.Amyloid-beta(Aβ)and tau proteins are among the main contributors to the AD progression.In AD,Aβproteins clump together to form plaques and disrupt cell functions.On the other hand,the abnormal chemical change in the brain helps to build sticky tau tangles that block the neuron’s transport system.Astrocytes generally maintain a healthy balance in the brain by clearing the Aβplaques(toxic Aβ).However,overactivated astrocytes release chemokines and cytokines in the presence of Aβand react to pro-inflammatory cytokines,further increasing the production of Aβ.In this study,we construct a mathematical model that can capture astrocytes’dual behavior.Furthermore,we reveal that the disease progression depends on the current time instance and the disease’s earlier status,called theamemory effect,omaking non-Markovian processes an appropriate approach.We consider a fractional order network mathematical model to capture the influence of such memory effects on AD progression.We have integrated brain connectome data into the model and studied the memory effect,the dual role of astrocytes,and the brain’s neuronal damage.Based on the pathology,primary,secondary,and mixed tauopathies parameters are considered in the model.Due to the mixed tauopathy,different brain nodes or regions in the brain connectome accumulate different toxic concentrations of Aβand tau proteins.Finally,we explain how the memory effect can slow down the propagation of such toxic proteins in the brain,decreasing the rate of neuronal damage.展开更多
This paper shows how the so called von Karman model can be obtained as a singular limit of a modified Mindlin-Timoshenko system when the modulus of elasticity in shear κ tends to infinity, provided a regularizing ter...This paper shows how the so called von Karman model can be obtained as a singular limit of a modified Mindlin-Timoshenko system when the modulus of elasticity in shear κ tends to infinity, provided a regularizing term through a fourth order dispersive operator is added. Introducing damping mechanisms, the authors also show that the energy of solutions for this modified Mindlin-Timoshenko system decays exponentially, uniformly with respect to the parameter k. As κ→∞, the authors obtain the damped von Karman model with associated energy exponentially decaying to zero as well.展开更多
We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of el...We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of electrodes for two electric field-actuated operations:electrowetting for merging droplets to mix reagents and electroporation for transformation.This device can perform up to 100 genetic modification reactions in parallel,providing a scalable platform for generating the large number of engineered strains required for the combinatorial optimization of genetic pathways and predictable bioengineering.We demonstrate the system's capabilities through the CRISPR-based engineering of two test cases:(1)disruption of the function of the enzyme galactokinase(galK)in£coli and(2)targeted engineering of the glutamine synthetase gene(glnA)and the blue-pigment synthetase gene(bpsA)to improve indigoidine production in£coli.展开更多
Nonlinear normal modes and a numerical iterative approach are applied to study the parametric vibrations of pipes conveying pulsating fluid as an example of gyroscopic continua.The nonlinear non-autonomous governing e...Nonlinear normal modes and a numerical iterative approach are applied to study the parametric vibrations of pipes conveying pulsating fluid as an example of gyroscopic continua.The nonlinear non-autonomous governing equations are transformed into a set of pseudo-autonomous ones by employing the harmonic balance method.The nonlinear normal modes are constructed by the invariant manifold method on the state space and a numerical iterative approach is adopted to obtain numerical solutions,in which two types of initial conditions for the modal coefficients are employed.The results show that both initial conditions can lead to fast convergence.The frequency-amplitude responses with some modal motions in phase space are obtained by the present iterative method.Quadrature phase difference and traveling waves are found in the time-domain complex modal analysis.展开更多
In this paper some new results concerning the C_p classes introduced by Muckenhoupt(1981)and later extended by Sawyer(1983),are provided.In particular,we extend the result to the full expected range p>0,to the weak...In this paper some new results concerning the C_p classes introduced by Muckenhoupt(1981)and later extended by Sawyer(1983),are provided.In particular,we extend the result to the full expected range p>0,to the weak norm,to other operators and to their vector-valued extensions.Some of those results rely upon sparse domination,which in the vector-valued case are provided as well.We will also provide sharp weighted estimates for vector-valued extensions relying on those sparse domination results.展开更多
A new solution methodology is proposed for solving efficiently Helmholtz problems.The proposed method falls in the category of the discontinuous Galerkin methods.However,unlike the existing solution methodologies,this...A new solution methodology is proposed for solving efficiently Helmholtz problems.The proposed method falls in the category of the discontinuous Galerkin methods.However,unlike the existing solution methodologies,this method requires solving(a)well-posed local problems to determine the primal variable,and(b)a global positive semi-definite Hermitian system to evaluate the Lagrange multiplier needed to restore the continuity across the element edges.Illustrative numerical results obtained for two-dimensional interior Helmholtz problems are presented to assess the accuracy and the stability of the proposed solution methodology.展开更多
基金the BERC 2018-2021 program and Spanish Ministry of Science,Innovation,and Universities through the Agencia Estatal de Investigacion(AEI)BCAM Severo Ochoa excellence accreditation SEV-2017-0718,and the Basque Government fund“AI in BCAM EXP.2019/00432”.
文摘Photosynthesis is a fundamental process in biosciences and biotechnology that influences profoundly the research in other disciplines.In this paper,we focus on the characterization of fundamental components,present in pigment-protein complexes,in terms of their spectroscopic properties such as infrared spectra,nuclear magnetic resonance,as well as nuclear quadrupole resonance,which are of critical importance for many applications.Such components include chlorophylls and bacteriochlorophylls.Based on the density functional theory method,we calculate the main spectroscopic characteristics of these components for the Fenna-Matthews-Olson light-harvesting complex,analyze them and compare them with available experimental results.Future outlook is discussed in the context of current and potential applications of the presented results.
基金BERC 2022-2025Natural Sciences and Engineering Research Council of Canada+4 种基金Alliance de recherche numérique du CanadaCanada Research ChairsBasque Government fund AIShared Hierarchical Academic Research Computer NetworkSpanish Ministry of Science,Innovation and Universities。
文摘Alzheimer’s disease(AD)is a common neurodegenerative disorder nowadays.Amyloid-beta(Aβ)and tau proteins are among the main contributors to the AD progression.In AD,Aβproteins clump together to form plaques and disrupt cell functions.On the other hand,the abnormal chemical change in the brain helps to build sticky tau tangles that block the neuron’s transport system.Astrocytes generally maintain a healthy balance in the brain by clearing the Aβplaques(toxic Aβ).However,overactivated astrocytes release chemokines and cytokines in the presence of Aβand react to pro-inflammatory cytokines,further increasing the production of Aβ.In this study,we construct a mathematical model that can capture astrocytes’dual behavior.Furthermore,we reveal that the disease progression depends on the current time instance and the disease’s earlier status,called theamemory effect,omaking non-Markovian processes an appropriate approach.We consider a fractional order network mathematical model to capture the influence of such memory effects on AD progression.We have integrated brain connectome data into the model and studied the memory effect,the dual role of astrocytes,and the brain’s neuronal damage.Based on the pathology,primary,secondary,and mixed tauopathies parameters are considered in the model.Due to the mixed tauopathy,different brain nodes or regions in the brain connectome accumulate different toxic concentrations of Aβand tau proteins.Finally,we explain how the memory effect can slow down the propagation of such toxic proteins in the brain,decreasing the rate of neuronal damage.
基金supported by INCTMat, FAPESQ-PB, CNPq (Brazil) under Grant Nos. 308150/2008-2 and 620108/2008-8the MICINN (Spain) under Grant No. MTM2008-03541+1 种基金the Advanced Grant FP7-246775 NUMERIWAVES of the ERCthe Project PI2010-04 of the Basque Government
文摘This paper shows how the so called von Karman model can be obtained as a singular limit of a modified Mindlin-Timoshenko system when the modulus of elasticity in shear κ tends to infinity, provided a regularizing term through a fourth order dispersive operator is added. Introducing damping mechanisms, the authors also show that the energy of solutions for this modified Mindlin-Timoshenko system decays exponentially, uniformly with respect to the parameter k. As κ→∞, the authors obtain the damped von Karman model with associated energy exponentially decaying to zero as well.
基金supported by the Basque Government through the BERC 2014-2017 program and the Spanish Ministry of Economy and Competitiveness MINECO through the BCAM Severo Ochoa excellence accreditation SEV-2013-0323Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia,LLC,a wholly owned subsidiary of Honeywell International,Inc.,for the U.S.Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525.
文摘We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of electrodes for two electric field-actuated operations:electrowetting for merging droplets to mix reagents and electroporation for transformation.This device can perform up to 100 genetic modification reactions in parallel,providing a scalable platform for generating the large number of engineered strains required for the combinatorial optimization of genetic pathways and predictable bioengineering.We demonstrate the system's capabilities through the CRISPR-based engineering of two test cases:(1)disruption of the function of the enzyme galactokinase(galK)in£coli and(2)targeted engineering of the glutamine synthetase gene(glnA)and the blue-pigment synthetase gene(bpsA)to improve indigoidine production in£coli.
基金This study was partially funded by the National Natural Science Foundation of China(Grant Nos.11672189,11672007)the postdoctoral fund of Beijing Chaoyang District(Grant No.Q5001015201602)+3 种基金the Program Funded by Liaoning Province Education Administration(Grant No.L2016010)Prof.X.-D.Yang was founded by the Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education,Northeastern University(VCAME201601)Prof.Melnik was funded by the Natural Sciences and Engineering Research Council(NSERC)of Canada,the Canada Research Chair(CRC)program,and the Bizkaia Talent Grant under the Basque Government through the BERC 2014-2017 programas well as Spanish Ministry of Economy and Competitiveness MINECO:BCAM Severo Ochoa excellence accreditation SEV-2013-0323.
文摘Nonlinear normal modes and a numerical iterative approach are applied to study the parametric vibrations of pipes conveying pulsating fluid as an example of gyroscopic continua.The nonlinear non-autonomous governing equations are transformed into a set of pseudo-autonomous ones by employing the harmonic balance method.The nonlinear normal modes are constructed by the invariant manifold method on the state space and a numerical iterative approach is adopted to obtain numerical solutions,in which two types of initial conditions for the modal coefficients are employed.The results show that both initial conditions can lead to fast convergence.The frequency-amplitude responses with some modal motions in phase space are obtained by the present iterative method.Quadrature phase difference and traveling waves are found in the time-domain complex modal analysis.
基金supported by the Basque Government through the Basque Excellence Research Centre 2018–2021 ProgramAgencia Estatal de Investigacion/European Regional Development Fund of UE(Grant No.MTM 2017-82160-C2-1-P),Acronym“Harmonic Analysis and Quantum Mechanics”+4 种基金Spanish Ministry of Economy and Competitiveness through Basque Center for Applied Mathematics Severo Ochoa Excellence Accreditation(Grant No.SEV-2013-0323)Universidad Nacional del Sur(Grant No.11/X752)Agencia Nacional de Promocion Cientifica y Tecnologica of Argentina(Grant No.PICT 2014-1771)Juan de la Cierva-Formacion2015(Grant No.FJCI-2015-24547)Consejo Nacional de Investigaciones Cientificas y Tecnicas/Proyectos de Investigacion Plurianuales of Argentina(Grant No.11220130100329CO)。
文摘In this paper some new results concerning the C_p classes introduced by Muckenhoupt(1981)and later extended by Sawyer(1983),are provided.In particular,we extend the result to the full expected range p>0,to the weak norm,to other operators and to their vector-valued extensions.Some of those results rely upon sparse domination,which in the vector-valued case are provided as well.We will also provide sharp weighted estimates for vector-valued extensions relying on those sparse domination results.
基金support by TOTAL and INRIA/CSUN Associate Team Magic,INRIA Bordeaux Sud-Ouest Center.Any opinions,findings,and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of TOTAL,INRIA or CSUN.
文摘A new solution methodology is proposed for solving efficiently Helmholtz problems.The proposed method falls in the category of the discontinuous Galerkin methods.However,unlike the existing solution methodologies,this method requires solving(a)well-posed local problems to determine the primal variable,and(b)a global positive semi-definite Hermitian system to evaluate the Lagrange multiplier needed to restore the continuity across the element edges.Illustrative numerical results obtained for two-dimensional interior Helmholtz problems are presented to assess the accuracy and the stability of the proposed solution methodology.
