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Botanicals and plant strengtheners for potato and tomato cultivation in Africa

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Journal of Integrative Agriculture 2020年第2期19卷 406-427页

作者： Tewodros MULUGETA Jean-Baptiste MUHINYUZA Reinette GOUWS-MEYER Lerato MATSAUNYANE erik ANDREASSON erik ALEXANDERSSON Department of Zoological Sciences Addis Ababa UniversityAddis Ababa 1000Ethiopia Department of Biology Kotebe Metropolitan UniversityAddis Ababa 1000Ethiopia College of Agriculture Animal Science and Veterinary Medicine(UR-CAVM)Busogo CampusUniversity of RwandaMusanze 210Rwanda Department of Crop Sciences Tshwane University of TechnologyPretoria 0183South Africa Department of Plant Breeding Agricultural Research Council-Vegetable and Ornamental PlantsPretoria 0001South Africa Department of Plant Protection Biology Swedish University of Agricultural Sciences(SLU)Alnarp SE-23053Sweden

This review provides a summary of botanicals and plant strengtheners that have potential uses for disease and pest management in potato and tomato cultivation in *** discuss their possible use to prevent major diseases and pests which infest potato and tomato,such as early and late blight,bacterial wilt,potato tuber moth,and tomato *** are several examples of the successful uses of botanicals for pathogen and pest control relevant for different African climatic conditions;however,most of these studies have been conducted in vitro and often lack field *** strengtheners(substances that induce and improve crop resistance,yield,and quality)are little studied and used in Africa in comparison to North America and *** possible benefits of using botanicals and plant strengtheners instead of conventional pesticides are discussed here in relation to human health and the environment as well as their modes of action and accessibility to *** of knowledge of the composition and active ingredients of extracts,environmental concerns,uncertainties regarding stability and formulation,lack of legislation and limited support from governments,hamper the development of botanicals and plant strengtheners for use in sustainable African agriculture.

关键词： African agriculture botanicals crop protection pathogen plant strengtheners pesticide pests diseases potato tomato

Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

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Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen erik Jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

A system for underground road condition monitoring

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International Journal of Mining Science and Technology 2020年第3期30卷 405-411页

作者： Max Astrand erik Jakobsson Martin Lindfors John Svensson kTH Royal Institute of Technology SE-10044 StockholmSweden ABB Corporate Research SE-72226 VästeråsSweden Epiroc SE-70191ÖrebroSweden Linköping University SE-58183 LinköpingSweden Boliden Mines SE-93632 BolidenSweden

Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to counteract this. The system consists of three components i.e. localization, road monitoring, and scheduling. The localization of vehicles is performed using a Rao-Blackwellized extended particle filter, combining vehicle mounted sensors with signal strengths of Wi Fi access points. Two methods for road monitoring are described: a kalman filter used together with a model of the vehicle suspension system, and a relative condition measure based on the power spectral density. Lastly, a method for taking automatic action on an ill-conditioned road segment is proposed in the form of a rescheduling *** scheduling algorithm is based on the large neighborhood search and is used to integrate road service activities in the short-term production schedule while minimizing introduced production *** system is demonstrated on experimental data collected in a Swedish underground mine.

关键词： Localization Road condition monitoring Scheduling Underground mining

Experimental Investigation of Effects of Reynolds Number and Incidence Angle on Secondary Flow within a Linear Blade Cascade

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Journal of Thermal Science 2021年第6期30卷 2122-2136页

作者： FLÍDR erik JELÍNEk Tomáš kLADRUBSkÝMilan Laboratory of High Speed Aerodynamics Czech Aerospace Research CenterBeranovych 130Prague 19905Czech Republic

The kinetic energy loss and the secondary loss downstream of a high turning nozzle cascade were *** of the incidence angle(i=-25°,0°and 25°)and Reynolds number(Re_(2,is)=0.8×10^(5),1.2×10^(5),2.5×10^(5) and 4.5×10^(5))were studied on two cascade configurations defined by different pitch to chord ratio(t/c=0.6 and 0.9),*** at the cascade inlet were performed by means of Preston tube,while at the cascade outlet by means of miniature pyramid five-hole pressure *** effect of studied parameters on the flow field at the cascade outlet was shown by the distribution of the kinetic energy loss,secondary loss,mix-out loss and streamwise vorticity.

关键词： linear blade cascade secondary loss pressure measurement

Environmental engineering of transition metal dichalcogenide optoelectronics

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Frontiers of physics 2018年第4期13卷 21-52页

作者： Trevor LaMountain erik J. Lenferink Yen-Jung Chen Teodor k. Stanev Nathaniel P. Stern Department of Physics and Astronomy Northwestern University Evanston Illinois 60208 USA

The explosion of interest in two-dimensional van der Waals materials has been in many ways driven by their layered geometry. This feature makes possible numerous avenues for assembling and ma- nipulating the optical and electronic properties of these materials. In the specific case of monolayer transition metal dichalcogenide semiconductors, the direct band gap combined with the flexibility for manipulation of layers has made this class of materials promising for optoelectronics. Here, we review the properties of these layered materials and the various means of engineering these properties for optoeleetronics. We summarize approaches for control that modify their structural and chemical en- vironment, and we give particular detail on the integration of these materials into engineered optical fields to control their optical characteristics. This combination of controllability from their layered surface structure and photonic environment provide an expansive landscape for novel optoelectronic phenomena.

关键词： transition metal dichalcogenides optoelectronics van der Waals materials heterostructures excitons

Comparison of the kobayashi-Royden and Sibony metrics on ring domains

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Science China Mathematics 2009年第12期52卷 2610-2616页

作者： FORN■SS John erik Department of Mathematics University of MichiganAnn ArborMichigan 48109USA

In this paper we show that the kobayashi-Royden metric and the Sibony metric are different on ring domains,i.e.,the difference of two concentric balls,in higher dimension.

关键词： kobayashi-Royden metric Sibony metric ring domain 32F45 32U05

Note on Resonant and Non-resonant Peaks in Electron-Atom Total Scattering Cross Sections

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Communications in Theoretical Physics 2018年第1期69卷 28-30页

作者： karl-erik Thylwe Patrick McCabe kTH-Mechanics Royal lnstitute of Technology CCDC

Certain broad low-energy peaks caused by a single partial wave in total cross sections are explained in terms of phase shifts. Such peaks have been associated with the real part of a Regge pole trajectory, having a maximum near an integer value of the angular momentum quantum number. At the peak energies, the pertinent partial-wave phase shift was shown to have a local maximum near a value π/2 modulo π. This implies no time delay in the semiclassical context. The phenomenon is a quantum effect, lacking a semiclassical interpretation.

关键词： scattering resonances quantum mechanics cross sections

Ultrasonic prediction of crack density using machine learning:A numerical investigation

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Geoscience Frontiers 2022年第1期13卷 114-126页

作者： Sadegh karimpouli Pejman Tahmasebi erik HSaenger Mining Engineering Group Faculty of EngineeringUniversity of ZanjanZanjanIran Department of Petroleum Engineering University of WyomingLaramieWY 82071USA Bochum University of Applied Sciences 44801 BochumGermany Fraunhofer IEG Fraunhofer Research Institution for Energy Infrastructure and Geothermal Systems44801 BochumGermany Ruhr-University Bochum 44801 BochumGermany

Cracks are accounted as the most destructive discontinuity in rock, soil, and concrete. Enhancing our knowledge from their properties such as crack distribution, density, and/or aspect ratio is crucial in geo-systems. The most well-known mechanical parameter for such an evaluation is wave velocity through which one can qualitatively or quantitatively characterize the porous media. In small scales, such information is obtained using the ultrasonic pulse velocity(UPV) technique as a non-destructive test. In large-scale geo-systems, however, it is inverted from seismic data. In this paper, we take advantage of the recent advancements in machine learning(ML) for analyzing wave signals and predict rock properties such as crack density(CD) – the number of cracks per unit volume. To this end, we designed numerical models with different CDs and, using the rotated staggered finite-difference grid(RSG) technique, simulated wave propagation. Two ML networks, namely Convolutional Neural Networks(CNN) and Long Short-Term Memory(LSTM), are then used to predict CD values. Results show that, by selecting an optimum value for wavelength to crack length ratio, the accuracy of predictions of test data can reach R2> 96% with mean square error(MSE) k density, without the necessity of further modeling.

关键词： Machine learning Crack density Ultrasonic wave Numerical computation

Efficient construction of linear models in materials modeling and applications to force constant expansions

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npj Computational Materials 2020年第1期6卷 527-537页

作者： erik Fransson Fredrik eriksson Paul Erhart Department of Physics Chalmers University of TechnologyGothenburgSweden

Linear models,such as force constant(FC)and cluster expansions,play a key role in physics and materials *** they can in principle be parametrized using regression and feature selection approaches,the convergence behavior of these techniques,in particular with respect to thermodynamic properties is not well ***,we therefore analyze the efficacy and efficiency of several state-of-the-art regression and feature selection methods,in particular in the context of FC extraction and the prediction of different thermodynamic properties.

关键词： properties thermodynamic constant