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Linking plant metabolism and immunity through methionine biosynthesis

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Molecular Plant 2022年第1期15卷 6-8页

作者： francisco Escaray Amelia Felipo-Benavent Pablo Vera Instituto de Biología Molecular y Celular de Plantas Universidad Politécnica de Valencia-C.S.I.CCiudad Politécnica de la InnovaciónEdificio 8EIngeniero Fausto Elios/n46022 ValenciaSpain

Plants respond to pathogenic cues with a transcriptional reprog-ramming that leads to de novo production of defense-related pro-teins and a huge variety of secondary metabolites(e.g.,phyto-alexins,phenolics,etc.).Activation of these host defenses,which contribute to halt the intruder as part of the resistance,im-plies an increased demand for metabolic energy and carbon skel-etons derived from primary metabolism(Bolton,2009).

关键词： metabolism immunity Bolton

Slip-model Performance for Underexpanded Micro-scale Rocket Nozzle Flows

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Journal of Thermal Science 2007年第3期16卷 223-230页

作者： JoséA.Morí■igo JoséHermidaQuesada francisco Caballero Requena Dept.of Space Programmes Dept.of

In aerospace Micro-Electro Mechanical Systems （MEMS）, the characteristic length scale of the flow approaches the molecular mean free path, thus invalidating the continuum description and enforcing the use of particle methods, like the Direct Simulation Monte Carlo （DSMC）, to deal with the non-equilibrium regions. Within the slip-regime （0.01〈Kn〈-0.1） both approaches, continuum and particle-based, seem to behave well in terms of accuracy. The present study summarizes the implementation and results obtained with a 2nO-order slip boundary condition in a Navier-Stokes solver to address the rarefaction near the nozzle walls. Its assessment and application to a cold-gas micro-scale conical nozzle of 300μm throat diameter, discharging into the low-pressure freestream, constitutes the major aim of the work. The slip-model incorporates the velocity slip with thermal creep and temperature jump, thus permitting to deal with non-isothermal flows as well. Results show that the gas experiences an intense rarefaction in the lip vicinity, pointing to the limits of model validity. Furthermore, a strong Mach deceleration is observed, attributed to the rather thick subsonic boundary layer and supersonic bulk heating caused by the viscous dissipation, in contrast with the expansion to occur in large rocket nozzles during underexpanded operation.

关键词： Slip flow MEMS micronozzles

Determining indoor air quality and identifying the origin of odour episodes in indoor environments

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Journal of Environmental Sciences 2009年第3期21卷 333-339页

作者： Eva Gallego Xavier Roca Jose francisco Perales Xavier Guardino Environmental Centre Laboratory Polytechnic University of Catalonia (LCMA-UPC) Avda Diagonal 647 E 08028 Barcelona Spain National Centre of Work Conditions (INSHT) Dulcet 2-10 E 08034 Barcelona Spain

A methodology for identifying volatile organic compounds （VOCs） and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive odorous and/or discomfort episodes. Glass multi-sorbent tubes are connected to the pump samplers for the retention of VOC. The analysis is performed by automatic thermal desorption （ATD） coupled with gas chromatography-mass spectrometry （GC/MS）. This methodology can be applied in cases of sick building syndrome （SBS） evaluation, in which building occupants experience a series of varied symptoms that appear to be linked to time spent in the building. Chemical pollutants concentrations （e.g., VOC） have been described to contribute to SBS. To exemplify the methodology, a qualitative determination and an evaluation of existing VOC were performed in a dwelling where the occupants experienced the SBS symptoms. Higher total VOC （TVOC） levels were detected during episodes in indoor air （1.33 ±1.53 mg/m^3） compared to outdoor air （0.71± 0.46 mg/m^3）. The concentrations of individual VOCs, such as ethanol, acetone, isopropanol, 1-butanol, acetic acid, acetonitrile and 1-methoxy-2-propanol, were also higher than the expected for a standard dwelling. The external source of VOC was found to be an undeclared activity of storage and manipulation of solvents located at the bottom of a contiguous building.

关键词： indoor air thermal desorption TVOC VOC sick building syndrome

Geography of Talent in China During 2000-2015:An Eigenvector Spatial Filtering Negative Binomial Approach

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Chinese Geographical Science 2021年第2期31卷 297-312页

作者： GU Hengyu francisco ROWE LIU Ye SHEN Tiyan School of Government Peking UniversityBeijing 100871China Geographic Data Science Lab Department of Geography and PlanningUniversity of LiverpoolLiverpool L69United Kingdom School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Guangdong Key Laboratory for Urbanization and Geo-Simulation Sun Yat-sen UniversityGuangzhou 510275China

The increase in China’s skilled labor force has drawn much attention from policymakers,national and international firms and *** how educated talent locates and re-locates across the country can guide future policy discussions of equality,firm localization and service *** studies have tended to adopt a static cross-national approach providing valuable insights into the relative importance of economic and amenity differentials driving the distribution of talent in ***,few adopt longitudinal analysis to examine the temporal dynamics in the stregnth of existing *** released official statistical data now enables space-time analysis of the geographic distribution of talent and its determinants in *** four-year city-level data from national population censuses and 1%population sample surveys conducted every five years between 2000 and 2015,we examine the spatial patterns of talent across Chinese cities and their underpinning drivers evolve over *** reveal that the spatial distribution of talent in China is persistently unequal and spatially concentrated between 2000 and *** also shows gradually strengthened and significantly positive spatial autocorrelation in the distribution of *** eigenvector spatial filtering negative binomial panel is employed to model the spatial determinants of talent *** indicate the influences of both economic opportunities and urban amenities,particularly urban public services and greening rate,on the distribution of *** results highlight that urban economic-and amenity-related factors have simultaneously driven China’s talent’s settlement patterns over the first fifteen years of the 21st century.

关键词： talent distribution determinants eigenvector spatial filtering panel data analysis China

Bioleaching of zinc from gold ores using Acidithiobacillus ferrooxidans

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 368-374页

作者： Pakawadee Kaewkannetra francisco Jose Garcia-Garcia Tze Yen Chiu Department of Biotechnology Faculty of TechnologyKhon Kaen University Corrosion and Protection Centre School of MaterialsThe University of Manchester Centre of Water Science Cranfield University

The present work investigated microbial leaching of zinc from ore using Acidithiobacillus ferrooxidans （ATCC 14859）. The ore samples, consisted of 13wt% zinc, were obtained from a gold mine in north-eastern Thailand. A shake flask study was performed on the ore samples using a rotary shaker under the following fixed conditions （250 r·min^-1, 30℃ for 16 d）. The influence of various conditions, namely medium type （with and without iron）, particle ore size （〈20, 20-40, 40-60, 60-100, and 〉100 mesh）, ore density （20 kg·m^-3, 50 kg·m^-3, and 100 kg·m^-3）, and pH of the medium （2, 2.5, 2.8, and 3）, were investigated. The microbial leaching was assessed by determining the concentration of zinc in the medium and compared with the initial sample concentration. The results show that Acidithiobacillus ferrooxidans can successfully leach zinc by as much as 6 times compared with the control experiment （without Acidithiobacillus ferrooxidans ferrooxidans）. The maximum efficiency （92.3%） for microbial leaching is obtained in iron-containing medium, 20-40 mesh ore sizes, 20 kg·m^-3 ore density at pH 2.8, and the zinc content is found in the medium at about 120 mg·m^-1.

关键词： bioleaching Acidithiobacillusferrooxidans gold ores gold mine

Frequency and distribution of neglected tropical diseases in Mozambique:a systematic review

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Infectious Diseases of Poverty 2019年第6期8卷 1-11页

作者： Berta Grau-Pujol Marilia Massangaie Jorge Cano Carmen Maroto Alcino Ndeve francisco Saute Jose munoz ISGIobal Hospital ClinicUniversitat de BarcelonaBarcelonaSpain Centro de Investigagao em Saude da Manhiga(CISM) MaputoMozambique mundo Sano Foundation Buenos AiresArgentina Direcgao Nacional de Saude Publica Ministerio da SaudeMaputoMozambique Faculty of Infectious and Tropical Diseases London School of Hygiene and Tropical MedicineLondonUK Liverpool School of Tropical Medicine LiverpoolUK No Leprosy Remains MaputoMozambique

Background:Neglected tropical diseases(NTDs)affect more than one billion people living in vulnerable *** spite of initiatives recently contributing to fill NTDs gaps on national and local prevalence and distribution,more epidemiological data are still needed for effective control and elimination *** text:Mozambique is considered one of the countries with highest NTDs burden although available data is *** study aims to conduct a systematic review on published available data about the burden and distribution of the different NTDs across Mozambique since January 1950 until December *** identified manuscripts from electronic databases(Pubmed,EmBase and Global Health)and paper publications and grey literature from Mozambique Ministry of *** fulfilling inclusion criteria were:crosssectional studies,ecological studies,cohorts,reports,systematic reviews,and narrative reviews capturing epidemiological information of endemic NTDs in ***-control studies,letters to editor,case reports and case series of imported cases were excluded.A total of 466 manuscripts were initially identified and 98 were finally included after the revision following PRISMA *** NTDs were reported in Mozambique during the study *** provinces(Nampula,Cabo Delgado,Niassa,Tete and Zambezia)and Maputo province had the higher number of NTDs *** disease had their own report profile:while schistosomiasis have been continuously reported since 1952 until nowadays,onchocerciasis and cysticercosis last available data is from 2007 and Echinococcosis have never been evaluated in the ***,both space and time gaps on NTDs epidemiology have been ***:This review assembles NTDs burden and distribution in ***,contributes to the understanding of NTDs epidemiology in Mozambique and highlights knowledge ***,the study provides key elements to progress towards the control and interrupti

关键词： Neglected tropical diseases Mozambique Africa Epidemiology Poverty Infectious diseases Review Helminth Trachoma Leprosy

A Sylvester-Based IMEXMethod via Differentiation Matrices for Solving Nonlinear Parabolic Equations

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Communications in Computational Physics 2013年第9期14卷 1001-1026页

作者： francisco de la Hoz Fernando Vadillo Department of Applied Mathematics Statistics and Operations ResearchFaculty of Science and TechnologyUniversity of the Basque Country UPV/EHUBarrio Sarriena S/N48940 LeioaSpain

In this paper we describe a new pseudo-spectral method to solve numerically two and three-dimensional nonlinear diffusion equations over unbounded domains,taking Hermite functions,sinc functions,and rational Chebyshev polynomials as basis *** idea is to discretize the equations by means of differentiation matrices and to relate them to Sylvester-type equations by means of a fourth-order implicit-explicit scheme,being of particular interest the treatment of three-dimensional Sylvester equations that we *** resulting method is easy to understand and express,and can be implemented in a transparent way by means of a few lines of *** test numerically the three choices of basis functions,showing the convenience of this new approach,especially when rational Chebyshev polynomials are considered.

关键词： Semi-linear diffusion equations pseudo-spectral methods differentiation matrices Hermite functions sinc functions rational Chebyshev polynomials IMEX methods Sylvester equations blow-up

EQUIVALENT UNIFORM DOSE SENSITIVITY TO CHANGES IN ABSORBED DOSE DISTRIBUTION

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International Journal of Biomathematics 2013年第1期6卷 129-142页

作者： francisco CUTANDA-HENRIQUEZ SILVIA VARGAS-CASTRILLON Hospital General Universitario Gregorio Mara~Sn Calle Doctor Esquerdo 46 28007 Madrid Spain Universidad Politdcnica de Madrid Ciudad Universitaria s/n 28040 Madrid Spain

Treatment planning in external beam radiation therapy （EBRT） utilizes dose volume histograms （DVHs） as optimization and evaluation tools. They present the fraction of planning target volume （PTV） receiving more than a given absorbed dose, against the absorbed dose values, and a number of radiobiological indices can be computed with their help. Equivalent uniform dose （EUD） is the absorbed dose that, uniformly imparted, would yield the same biological effect on a tumor as the dose distribution described by the DVH. Uncertainty and missing information can affect the dose distribution, therefore DVHs can be modeled as samples from a set of possible outcomes. This work studies the sensitivity of the EUD index when a small change in absorbed dose distribution takes place. EUD is treated as a functional on the set of DVHs. Defining a Levy distance on this set and using a suitable expansion of the functional, a very simple expression for a bound on the variation of EUD when the dose distribution changes is found. This bound is easily interpreted in terms of standard treatment planning practice.

关键词： Equivalent uniform dose DVH von Mises differential.

Stability analysis of slopes with planar failure using variational calculus and numerical methods

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1262-1273页

作者： Norly BELANDRIA RobertoÚCAR francisco M.LEON Ferri HASSANI Geological Engineering School University of Los AndesMérida 5101Venezuela Mechanical Engineering School University of Los AndesMérida 5101Venezuela Department of Mining and Material Engineering McGill UniversityMontrealQC H3A 0E9Canada

This study investigates the technique of variational calculus applied to estimate the slope stability considering the mechanism of planar *** critical plane failure surface should be determined because it theoretically indicates the most unfavorable plane to be considered when stabilizing a slope to rectify the instability generated by several statistically possible *** generates integrals that can be solved by numerical methods,such as the Newton Cotes and the finite differences ***,a system of nonlinear equations is obtained and *** surface of the critical planar failure is determined by applying the condition of transversality in mobile boundaries,for which various examples are *** number of slices is varied in one of the examples,while the surface of the critical planar failure is determined in the *** are compared using analytical methods through axis *** the results obtained by considering normal stress,safety factors,and critical planar failure are nearly the same;however,in this research,a study is carried out for“n”number of slices using programming ***-routines are important because they can be applied in slopes with different geometry,surcharge,interstitial pressure,and pseudo-static load.

关键词： slopes stability planar failure variational calculus numerical methods