Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertic...Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.展开更多
In this paper, we use the global search characteristics of genetic algorithms to help search the weight space of the neurons in the cascade-correlation architecture. The cascade-correlation learning architecture is a ...In this paper, we use the global search characteristics of genetic algorithms to help search the weight space of the neurons in the cascade-correlation architecture. The cascade-correlation learning architecture is a technique of training and building neural networks that starts with a simple network of neurons and adds additional neurons as they are needed to suit a particular problem. In our approach, instead ofmodifying the genetic algorithm to account for convergence problems, we search the weight-space using the genetic algorithm and then apply the gradient technique of Quickprop to optimize the weights. This hybrid algorithm which is a combination of genetic algorithms and cascade-correlation is applied to the two spirals problem. We also use our algorithm in the prediction of the cyclic oxidation resistance of Ni- and Co-base superalloys.展开更多
Let A be an abelian category and M∈A.Then M is called a(D_(4))-object if,whenever A and B are subobjects of M with M=A⊕B and f:A→B is an epimorphism,Ker f is a direct summand of A.In this paper we give several equi...Let A be an abelian category and M∈A.Then M is called a(D_(4))-object if,whenever A and B are subobjects of M with M=A⊕B and f:A→B is an epimorphism,Ker f is a direct summand of A.In this paper we give several equivalent conditions of(D_(4))-objects in an abelian category.Among other results,we prove that any object M in an abelian category A is(D_(4))if and only if for every subobject K of M such that K is the intersection K_(1)∩K_(2)of perspective direct summands K_(1)and K_(2)of M with M=K_(1)+K_(2),every morphismφ:M→M/K can be lifted to an endomorphismθ:M→M in End _(A)(M).展开更多
1 Introduction Ring Opening Metathesis Polymerization(ROMP)is based on the olefin metathesis reaction,which requires transition metal catalysts.Mainly molybdenum,tungsten and ruthenium based catalysts have up to now b...1 Introduction Ring Opening Metathesis Polymerization(ROMP)is based on the olefin metathesis reaction,which requires transition metal catalysts.Mainly molybdenum,tungsten and ruthenium based catalysts have up to now been used.The“in-between”metal rhenium was only rarely applied in olefin metathesis reactions,and not at all in ROMP processes.We have found that cationic phosphine substituted dinitrosyl rhenium complexes 1a and 1b effectively catalyze ROMP of norbonene,dicyclopentadiene and of cyclooctene.See Fig.1.展开更多
Introduction:Yellow fever(YF)is primarily transmitted by Haemagogus species of mosquitoes.Under climate change,mosquitoes and the pathogens that they carry are expected to develop faster,potentially impacting the case...Introduction:Yellow fever(YF)is primarily transmitted by Haemagogus species of mosquitoes.Under climate change,mosquitoes and the pathogens that they carry are expected to develop faster,potentially impacting the case count and duration of YF outbreaks.The aim of this study was to determine how YF virus outbreaks in Brazil may change under future climate,using ensemble simulations from regional climate models under RCP4.5 and RCP8.5 scenarios for three time periods:2011-2040(short-term),2041-2070(mid-term),and 2071-2100(long-term).Methods:A compartmental model was developed to fit the 2017/18 YF outbreak data in Brazil using least squares optimization.To explore the impact of climate change,temperature-sensitive mosquito parameters were set to change over projected time periods using polynomial equations fitted to their relationship with temperature according to the average temperature for years 2011-2040,2041-2070,and 2071-2100 for climate change scenarios using RCP4.5 and RCP8.5,where RCP4.5/RCP8.5 corresponds to intermediate/high radiative forcing values and to moderate/higher warming trends.A sensitivity analysis was conducted to determine how the temperature-sensitive parameters impacted model results,and to determine how vaccination could play a role in reducing YF in Brazil.Results:Yellow fever case projections for Brazil from the models varied when climate change scenarios were applied,including the peak clinical case incidence,cumulative clinical case incidence,time to peak incidence,and the outbreak duration.Overall,a decrease in YF cases and outbreak duration was observed.Comparing the observed incidence in 2017/18 to the projected incidence in 2070-2100,for RCP4.5,the cumulative case incidence decreased from 184 to 161,and the outbreak duration decreased from 21 to 20 weeks.For RCP8.5,the peak case incidence decreased from 184 to 147,and the outbreak duration decreased from 21 to 17 weeks.The observed decrease was primarily due to temperature increasing beyond that suitable for Haemagogus mosquito sur展开更多
基金funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Project MEMS4.0,ERC-2016-ADG,grant agreement No.742685)the EU’s H2020 framework program for research and innovation under grant agreement n.101007417,NFFA-Europe Pilot Project.M.B.acknowledges the support of SNSF Eccellenza grant No.PCEGP2_194528+4 种基金support from the QuantERA II Programme that has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No 101017733G.F.and M.P.received funding through the European research council H2020-UE Framework Programme for Research&Innovation(2014-2020)ERC-2017-CoGInCellProject number 773091,and the Swiss National Science Foundation through grant 200021_182562.
文摘Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.
文摘In this paper, we use the global search characteristics of genetic algorithms to help search the weight space of the neurons in the cascade-correlation architecture. The cascade-correlation learning architecture is a technique of training and building neural networks that starts with a simple network of neurons and adds additional neurons as they are needed to suit a particular problem. In our approach, instead ofmodifying the genetic algorithm to account for convergence problems, we search the weight-space using the genetic algorithm and then apply the gradient technique of Quickprop to optimize the weights. This hybrid algorithm which is a combination of genetic algorithms and cascade-correlation is applied to the two spirals problem. We also use our algorithm in the prediction of the cyclic oxidation resistance of Ni- and Co-base superalloys.
文摘Let A be an abelian category and M∈A.Then M is called a(D_(4))-object if,whenever A and B are subobjects of M with M=A⊕B and f:A→B is an epimorphism,Ker f is a direct summand of A.In this paper we give several equivalent conditions of(D_(4))-objects in an abelian category.Among other results,we prove that any object M in an abelian category A is(D_(4))if and only if for every subobject K of M such that K is the intersection K_(1)∩K_(2)of perspective direct summands K_(1)and K_(2)of M with M=K_(1)+K_(2),every morphismφ:M→M/K can be lifted to an endomorphismθ:M→M in End _(A)(M).
文摘1 Introduction Ring Opening Metathesis Polymerization(ROMP)is based on the olefin metathesis reaction,which requires transition metal catalysts.Mainly molybdenum,tungsten and ruthenium based catalysts have up to now been used.The“in-between”metal rhenium was only rarely applied in olefin metathesis reactions,and not at all in ROMP processes.We have found that cationic phosphine substituted dinitrosyl rhenium complexes 1a and 1b effectively catalyze ROMP of norbonene,dicyclopentadiene and of cyclooctene.See Fig.1.
文摘Introduction:Yellow fever(YF)is primarily transmitted by Haemagogus species of mosquitoes.Under climate change,mosquitoes and the pathogens that they carry are expected to develop faster,potentially impacting the case count and duration of YF outbreaks.The aim of this study was to determine how YF virus outbreaks in Brazil may change under future climate,using ensemble simulations from regional climate models under RCP4.5 and RCP8.5 scenarios for three time periods:2011-2040(short-term),2041-2070(mid-term),and 2071-2100(long-term).Methods:A compartmental model was developed to fit the 2017/18 YF outbreak data in Brazil using least squares optimization.To explore the impact of climate change,temperature-sensitive mosquito parameters were set to change over projected time periods using polynomial equations fitted to their relationship with temperature according to the average temperature for years 2011-2040,2041-2070,and 2071-2100 for climate change scenarios using RCP4.5 and RCP8.5,where RCP4.5/RCP8.5 corresponds to intermediate/high radiative forcing values and to moderate/higher warming trends.A sensitivity analysis was conducted to determine how the temperature-sensitive parameters impacted model results,and to determine how vaccination could play a role in reducing YF in Brazil.Results:Yellow fever case projections for Brazil from the models varied when climate change scenarios were applied,including the peak clinical case incidence,cumulative clinical case incidence,time to peak incidence,and the outbreak duration.Overall,a decrease in YF cases and outbreak duration was observed.Comparing the observed incidence in 2017/18 to the projected incidence in 2070-2100,for RCP4.5,the cumulative case incidence decreased from 184 to 161,and the outbreak duration decreased from 21 to 20 weeks.For RCP8.5,the peak case incidence decreased from 184 to 147,and the outbreak duration decreased from 21 to 17 weeks.The observed decrease was primarily due to temperature increasing beyond that suitable for Haemagogus mosquito sur
