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Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen Ryan p.Russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its.partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's.problem two-body dynamics primer vectortheory

palladium-catalyzed s_(N)2 glycosylation of phenols

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science China Chemistry 2024年第4期67卷 1037-1038页

作者： Yu Zhu p.Andrew Evans Department of Chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya school of pharmaceutical sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs.present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties palladium catalyzed

Efficiency and effectiveness of systems for the treatment of domestic wastewater based on subsurface flow constructed wetlands in Jarabacoa, Dominican Republic

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Water science and Engineering 2024年第2期17卷 118-128页

作者： Yvelisse pérez Enmanuel Vargas Daniel Garcia-Cortes William Hernandez Humberto Checo Ulises Jauregui-Haza Area de Ciencias Basicas y Ambientales Instituto Tecnologico de Santo Domingo(INTEC)Avenida de Los Proceres 49Los Jardines del NorteSanto Domingo 10602Dominican Republic Ministry of Environment and Natural Resources Calle Cayetano Germosen esq.Ave.LuperonEl PedregalSanto Domingo 11107Dominican Republic plan Yaque Calle Estela Geraldino 14 AltosJarabacoa 41000Dominican Republic Institute of Technologies and Applied sciences University of HavanaHavana 10400Cuba

Constructed wetlands(CwW)are well known nature-based systems for water *** study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in Jarabacoa,the Dominican *** results showed that the CWs were efficient in reducing the degree of contamination of wastewater to levels below the Dominican wastewater discharge standards for parameters such as the 5-day biochemical oxygen demand(BOD5)and chemical oxygen demand,but not for the removal of phosphorus and fecal *** addition,a horizontal flow subsurface wetland in the peri-urban area El Dorado was evaluated in terms of the performance of wastewater treatment in tropical climatic *** concentrations of heavy metals,such as zinc,copper,chromium,and iron,were found to decrease in the effluent of the wetland,and the concentrations for nickel and manganese tended to *** levels of heavy metals in the effluent were lower than the limit values of the Dominican wastewater discharge *** construction cost of these facilities was around 200 UsD per population equivalent,similar to the cost in other countries in the same *** study suggested some solutions to the improved performance of CWs:selection of a microbial flora that guarantees the reduction of nitrates and nitrites to molecular nitrogen,use of endemic plants that bioaccumulate heavy metals,combination of constructed wetlands with filtration on activated carbon,and inclusion of water purification processes that allow to evaluate the reuse of treated water.

关键词： Domestic wastewater Constructed wetland BOD COD pathogens Heavy metals

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura García-Mendívil María pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-Gil Javier Fañanás-Mastral Manuel Vázquez-sancho Javier AndréBellido-Morales Alexánder sebastián Vaca-Núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordovás Esther pueyo Biomedical signal Interpretation and Computational simulation group(BsICos) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BsICos Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiovascular surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its.potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent

Biomass gasification,catalytic technologies and energy integration for production of circular methanol:New horizons for industry decarbonisation

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Journal of Environmental sciences 2024年第6期140卷 306-318页

作者： Luis F.Bobadilla Lola Azancot Miriam González-Castañ Estela Ruíz-López Laura pastor-pérez Francisco J.Durán-Olivencia Runping Ye Katie Chong paula HBlanco-sánchez Zenthao Wu Tomás R.Reina JoséA.Odriozola Departamento de Química Inorgánica e Instituto de Ciencia de Materiales de sevilla Centro Mixto CSIC-Universidad de SevillaAvda.Américo Vespucio 49Sevilla 41092Spain Departamento de Ingeniería Universidad Loyola AndalucíaAvda.de Las Universidades s/nSevilla 41704Spain Key Laboratory of Jiangxi province for Environment and Energy Catalysis School of Chemistry and Chemical EngineeringNanchang UniversityNanchang330031China Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirminghamB47ETUnited Kingdom Department of Chemical and process Engineering University of SurreyGuildfordGU27XHUnited Kingdom

The Intergovernmental panel on Climate Change(IpCC)recognises the pivotal role of renewable energies in the future energy system and the achievement of the zero-emission *** implementation of renewables should provide major opportunities and enable a more secure and decentralised energy s.pply *** fuels.provide long-term solutions for the transport sector,particularly for applications where fuels with high energy density are *** addition,it helps reducing the carbon footprint of these sectors in the *** on biomass characteristics feedstock is essential for scaling-up gasification from the laboratory to *** review deals with the transformation biogenic residues into a valuable bioenergy carrier like biomethanol as the liquid sunshine based on the combination of modified mature technologies such as gasification with other innovative solutions such as membranes and microchannel *** abatement is a critical process in product gas upgrading since tars compromise downstream processes and equipment,for this,membrane technology for upgrading syngas quality is discussed in this *** reactor technology with the design of state-of-the-art multifunctional catalysts.provides a path to develop decentralised biomethanol synthesis from biogenic ***,the development of a process chain for the production of(i)methanol as an intermediate energy carrier,(ii)electricity and(iii)heat for decentralised applications based on biomass feedstock flexible gasification,gas upgrading and methanol synthesis is analysed.

关键词： Biogenic residues Gasification Biomethanol Circular Economy Microreactors

photosynthetic Gas Exchange and Nitrogen Assimilation in Green Bean plants s.pplied with Two sources of silicon

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phyton-International Journal of Experimental Botany 2024年第5期93卷 963-980页

作者： Julio C.Anchondo-páez Esteban sánchez Carlos A.Ramírez-Estrada Alondra salcido-Martínez Erick H.Ochoa-Chaparro Department of plant physiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins.proteins,calcium,and zinc which make them an important food source for many *** meet the demand for bean production worldwide,large amounts of fertilizers and pesticides are ***,the cost of production and environmental impact *** produce food sustainably,the use of beneficial nutrients such as silicon as a biostimulant has been ***,information about the effect of different sources of silicon on the metabolism of bean plants is *** plants *** were grown in pots for 60 days and the effect of foliar application of silicon nanoparticles and the silicon-based biostimulant Codasilat 4 concentrations(0,1,2,and 4 mM)on total biomass,yield,photosynthetic pigment concentration,photosynthetic activity,stomatal conductance,transpiration rate,chlorophyll fluorescence,and nitrogen assimilation were *** results obtained showed that the s.pply of silicon at a dose of 1 mM functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the plant,which stimulated growth and *** results of this research work allowed a better comprehension of the effects of silicon application through silicon nanoparticles and the biostimulant Codasilon the physiology of green bean plants.

关键词： Nanoparticles silicon phaseolus vulgaris L.

Design & Test of an Advanced Web security Analysis Tool (AWsAT)

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Journal of software Engineering and Applications 2024年第5期17卷 448-461页

作者： Meenakshi s. p. Manikandaswamy Vijay Madisetti school of Cybersecurity and privacy Georgia Institute of Technology Atlanta USA

Considering the escalating frequency and s.phistication of cyber threats targeting web applications, this.paper proposes the development of an automated web security analysis tool to address the accessibility gap for non-security professionals. This.paper presents the design and implementation of an automated web security analysis tool, AWsAT, aimed at enabling individuals with limited security expertise to effectively assess and mitigate vulnerabilities in web applications. Leveraging advanced scanning techniques, the tool identifies common threats such as Cross-site scripting (Xss), sQL Injection, and Cross-site Request Forgery (CsRF), providing detailed reports with actionable insights. By integrating sample payloads and reference study links, the tool facilitates informed decision-making in enhancing the security posture of web applications. Through its user-friendly interface and robust functionality, the tool aims to democratize web security practices, empowering a wider audience to proactively safeguard against cyber threats.

关键词： Web security Automated Analysis Vulnerability Assessment Web scanning Cross-site scripting sQL Injection Cross-site Request Forgery

Fuzzy Inventory Model under selling price Dependent Demand and Variable Deterioration with Fully Backlogged shortages

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American Journal of Operations Research 2024年第2期14卷 87-103页

作者： Tanzim s. shaikh santosh p. Gite Department of statistics University of Mumbai Mumbai India

The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. shortages are allowed and fully backlogged. Fuzzy optimal solution is obtained by considering hexagonal fuzzy numbers and for defuzzification Graded Mean Integration Representation Method. A numerical example is.provided for the illustration of crisp and fuzzy, both models. To observe the effect of changes in parameters, sensitivity analysis is carried out.

关键词： Deterioration selling price Dependent Demand Fully Backlogged Hexagonal Fuzzy Numbers Graded Mean Integration Representation Method

Immune response to inactivated bacterial vector carrying the recombinant K39 antigen of Leishmania infantum in mice

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Asian pacific Journal of Tropical Biomedicine 2024年第5期14卷 199-206页

作者： Lucelina s.Araújo Bruno B.silva Eduarda N.F.N.santos Arnaldo s.Bezerra samuel s.Frota Assis R.Montenegro Eridan O.p.T.Florean Maurício Fvan Tilburg Maria Izabel F.Guedes Laboratory of Biotechnology and Molecular Biology Northeast Biotechnology NetworkState University of CearáFortalezaBrazil Faculty of Veterinary Medicine State University of CearáFortalezaBrazil

Objective:To evaluate the immunological response elicited by an inactivated bacterial vector carrying the K39 antigen of Leishmania infantum,and a purified ***:Mice were subjected to the following treatments:(1)purified recombinant K39(rK39)protein at a 20μg dose with complete Freund’s adjuvant;(2)Inactivated Escherichia coli(BL21 DE3)carrying the K39 protein at an equivalent total protein content of 200μg;(3)Inactivated bacteria lacking the K39 protein;(4)Non-immunized control *** monitoring was *** groups were challenged by intraperitoneal injection of 10^(7) Leishmania infantum *** euthanasia,the liver and spleen were collected to analyze the levels of TNF,IFN-γ,IL-12,IL-4,and ***:Mice immunized with purified rK39 or the inactivated bacterial vector carrying the K39 antigen of Leishmania infantum showed a long-lasting immune response with high levels of polyclonal antibodies specifically recognizing the recombinant *** IgG1 subclass was the predominant immunoglobulin;however,the induction of IgG2a and the profile of cytokines.produced were indicative of the induction of a mixed-type ***:The inactivated bacterial vector carrying the K39 antigen,as well as the purified antigen can induce a long-lasting immune response in immunized mice,predominantly favouring a Th2 profile response.

关键词： Visceral leishmaniasis K39 Inactivated bacterial vector Vaccine Immune response Th1 Th2 Leishmania infantum