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Microorganisms in Small Patterned Ground Features and Adj.cent Vegetated Soils along Topographic and Climatic Gradients in the High Arctic, Canada

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Open j.urnal of Soil Science 2014年第1期4卷 47-55页

作者： Grizelle gonzález francisco j. Rivera-Figueroa William A. Gould Sharon A. Cantrell j.sé R. Pérez-j.ménez International Institute of Tropical Forestry (IITF) USDA Forest Service Río Piedras Puerto Rico School of Science and Tech- nology Universidad del Turabo Gurabo Puerto.

In this study, we determine differences in total biomass of soil microorganisms and community structure (using the most probable number of bacteria (MPN) and the number of fungal genera) in patterned ground features (PGF) and adj.cent vegetated soils (AVS) in mesic sites from three High Arctic islands in order to characterize microbial dynamics as affected by cryoturbation, and a broad bioclimatic gradient. We also characterize total biomass of soil microorganisms and the most probable number of bacteria along a topographic gradient within each bioclimatic subzone to evaluate whether differences in topography lead to differences in microbial dynamics at a smaller scale. We found total microbial biomass C, the most probable number of heterotrophic bacteria, and fungal genera vary along this bioclimatic gradient. Microbial biomass C decreased with increasing latitude. Overall, microbial biomass C, MPN and the number of fungal isolates were higher in AVS than in PGFs. The effects which topographic position had on microbial biomass C varied across the bioclimatic gradient as there was no effect of topographic position in Isachsen (subzone A) and Mould Bay (subzone B), when compared to Green Cabin (subzone C, warmer site).There was no effect of topographic position on MPN counts at Mould Bay and Green Cabin. However, in Isachsen, MPN counts were highest in the wet topographic position as compared to the mesic and dry. In conclusion, PGFs seem to decouple the effect climate that might have on the total biomass of soil microorganisms along the bioclimatic gradient;and influence gets ameliorated as latitude increases. Similarly, the effect of topography on the total microbial biomass is significant at the warmest bioclimatic zone of the gradient. Thus, climate and topographic effects on total microbial biomass increase with warmer climate.

关键词： Soil Microorganisms High Artic Canada Patterned Features Microbial Biomass

Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

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Nano Research 2023年第5期16卷 7470-7480页

作者： Pablo Purohit francisco j.Fortes j.vier Laserna UMALASERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

Simulating FAS-induced apoptosis by using P systems

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Progress in Natural Science:Materials International 2007年第4期17卷 424-431页

作者： Smitha Cheruku Andrei Pǎun francisco j. Romero-Campero Mario j. Pérez-j.ménez Oscar H. Ibarra Department of Computer Science/IfM Louisiana Tech UniversityP.O. Box 10348RustonLA 71272USA Department of Computer Science and Artificial Intelligence University of SevilleAvda. Reina Mercedes s/n 41012SevillaSpain Department of Computer Science University of California-Santa BarbaraSanta BarbaraCA 93106USA

In contrast to differential equations, P systems are an unconventional model of computation which takes into consideration the discrete character of the quantity of components and the inherent randomness that exists in biological phenomena. The key feature of P systems is their compartmentalised structure which represents the heterogeneity of the structural organisation of the cells, and where one can take into account the role played by membranes in the functioning of the system, for example signalling at the cell surface, selective uptake of substances from the media, diffusion across different compartments, etc. We show here that P systems can be a reliable tool for Systems Biology and could even outperform in some cases the current simulation techniques based on differential equations. We will also use a strategy based on the well known Gillespie algorithm but running on more than one compartment called Multi-compartmental Gillespie Algorithm.

关键词： FAS-induced apoptosis P systems deterministic waiting times algorithm multi-compartmental Gillespie algorithm.

Real Renormings on Complex Banach Spaces

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Chinese Annals of Mathematics,Series B 2008年第3期29卷 239-246页

作者： francisco j.GARC■A-PACHECO Alej.ndro MIRALLES Department of Mathematical Sciences Kent State University Departamento de Análisis Matemático Universidad de Valencia

The authors prove that every complex Banach space admits an equivalent real norm that is far away from being a complex norm. Furthermore, this real norm can be chosen to share many properties with complex norms, but i... 详细信息

关键词： Complex norms Real norms Hilbert space

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Presence of <i>Actinobacillus pleuropneumoniae, Streptococcus suis, Pasteurella multocida, Bordetella bronchiseptica, Haemophilus parasuis and Mycoplasma hyopneumoniae</i>in upper respiratory tract of swine in farms from Aguascalientes, Mexico

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Open j.urnal of Animal Sciences 2013年第2期3卷 132-137页

作者： Abraham Loera-Muro francisco j. Avelar-gonzález Víctor M. Loera-Muro Mario j.cques Alma L. Guerrero-Barrera Centro de Ciencias Básicas Universidad Autónoma de Aguascalientes Aguascalientes México Groupe de recherche sur les maladies infectieuses du porc Faculté de Médecine Vétérinaire Université de Montréal St-Hyacinthe Canada Laboratorio de Biología Celular y Tisular Departamento de Morfología Centro de Ciencias Básicas Universidad Autónoma de Aguascalientes Aguascalientes México

Respiratory diseases are one of the most important health problems in pig herds. The porcine respiratory disease complex (PRDC) is the term used to describe pneumonic diseases caused by multiple infectious agents that provoke weight loss in animals or death. In the PRDC multiple pathogens (bacteria and/or viruses) work in combination to induce this respiratory disease. Within this complex, Actinobacillus pleuropneumoniae, Streptococcus suis, Pasteurella multocida, Bordetella bronchiseptica, Haemophilus parasuis and Mycoplasma hyopneumoniae are the main bacterial pathogens involved in great economic losses to the swine industry. The aim of this work was to estimate the presence of A. pleuropneumoniae, S. suis, P. multocida, B. bronchiseptica, H. parasuis and M. hyopneumoniae in the upper respiratory tract of pigs in representative swine farms inAguascalientes,Mexico, using PCR technique. The study was performed in 14 swine farms. We obtained a total of 212 nasal swabs. Near 20% of samples were positive for A. pleuropneumoniae (located in the 79% of farms);17% were positive for S. suis (in 86% of farms), of these, 3% were S. suis serovar 2;30% were positive for H. parasuis (93% of farms);23% of the samples to P. multocida (in 79% of farms);and 19% to M. hyopneumoniae (in 64% of farms). B. bronchiseptica was not detected in this study. The results obtained show that bacterial pathogens of PRDC were present in the upper respiratory tract of pigs in all farms studied;therefore, these pathogens are widely disseminated in pig farms of Aguascalientes, Mexico.

关键词： Porcine Respiratory Disease Complex Actinobacillus pleuropneumoniae Streptococcus suis Pasteurella multocida Bordetella bronchiseptica Haemophilus parasuis Mycoplasma hyopneumoniae

How to express tumours using membrane systems

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Progress in Natural Science:Materials International 2007年第4期17卷 449-457页

作者： Miguel A. Gutiérrez-Naranj. Mario j. Pérez-j.ménez Agustín Riscos-Núez francisco j. Romero-Campero Department of Computer Science and Artificial Intelligence University of Seville Avda. Reina Mercedes s/n41012SevillaSpain

In this paper we discuss the potential usefulness of membrane systems as tools for modelling tumours. The approach is followed both from a macroscopic and a microscopic point of view. In the first case, one considers the tumour as a growing mass of cells, focusing on its external shape. In the second case, one descends to the microscopic level, studying molecular signalling pathways that are crucial to determine if a cell is cancerous or not. In each of these approaches we work with appropriate variants of membrane systems.

关键词： tumour membrane system modeling.

NADPH Thioredoxin Reductase C Is Involved in Redox Regulation of the Mg-Chelatase I Subunit in Arabidopsis thaliana Chloroplasts

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Molecular Plant 2014年第7期7卷 1252-1255页

作者： j.an Manuel Pérez-ruiz Manuel Guinea Leonor Puerto-Galán francisco j.vier Cej.do Instituto de Bioquímica Vegetal y Fotosíntesis Universidad de Sevilla-Consejo Superior de Investigaciones Científicas 41092-Sevilla Spain Umea Plant Science Centre Department of Plant Physiology Umea University S-901 87 Umea Sweden

Dear Editor, The synthesis of tetrapyrroles, including chlorophylls, is central for chloroplast function. The metabolic pathway of tetrapyrrole biosynthesis in Arabidopsis is initiated with the formation of amino levulinic acid （ALA）, which is con- verted by a series of common reactions to protoporphy- tin IX （Proto IX）（Tanaka et al., 2011）. Then the pathway diverges into two branches： the synthesis of heme/bilin and chlorophylls. The insertion of Mg2＋ into Proto IX, cata- lyzed by Mg-chelatase, is the first committed reaction of the chlorophyll branch and is considered a key step for the regulation of the whole pathway. Mg-chelatase is a het- erotrimeric enzyme composed of subunits CHLI, CHLD, and CHLH, the reaction mechanism of which has been estab- lished. It is a two-step process consisting in the Mg-ATP- dependent activation of the enzyme, which implies the formation of a ternary complex of subunits CHLI and CHLD with ATP-Mg2＋, and Mg2＋ chelation, which is catalyzed by CHLH driven by ATP hydrolysis, CHLI providing ATPase activity to the complex （Tanaka et al., 2011）. In Arabidopsis, CHLH and CHLD are encoded by single genes, whereas two genes, CHLI-I and CHLI-2, encode the two isoforms of CHLI.

关键词： synthesis of tetrapyrroles chlorophylls Arabidopsis

Innovative circular path harvester for mechanical harvesting of irregular and large-canopy olive trees

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International j.urnal of Agricultural and Biological Engineering 2018年第3期11卷 86-93页

作者： Rafael R.Sola-Guirado Gregorio L.Blanco-Roldan Sergio Castro-Garcia francisco j.Castillo-ruiz j.sus A.Gil-Ribes Department of Rural Engineering E.T.S.I.Agronomos y MontesUniversity of CordobaCampus de RabanalesCtra.Nacional IV Km 396CordobaSpain

The harvesting process of the olive tree is mainly performed by manual means,because traditional olive orchards(the main planting typology)are formed of irregular,large-canopy trees that are very difficult to harvest *** that reason,the cost of harvesting is very high,and it threatens the future of these plantations whose conversion to other more modern layouts is not always possible due to several *** introduction of a harvester may represent the technological change that is the key factor for improved *** main purpose of this work was to develop a harvester based on canopy shaker technology for work on irregular,large trees in a circular *** design of the harvester was based on a determination of tree geometry,together with tree *** tests were used to determine machine-tree interaction,and to evaluate the removal,catch frame and driven *** proposed innovation allowed the fully mechanical harvest of previously planted trees with a removal efficiency of over 84%,achieving an effective field capacity of 0.21 hm^(2)/*** the results so far have been promising,further improvements are advisable in machine and tree adaptation.

关键词： olive tree olive fruit canopy shaker harvester machinery design

A SHORT NOTE ABOUT EXPOSED POINTS IN REAL BANACH SPACES

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Acta Mathematica Scientia 2008年第4期28卷 797-800页

作者： Antonio Aizpuru francisco j.Garcia-Pacheco Departamento de Matemá ticas Universidad de Cá diz Department of Mathematical Sciences Kent State University

We express the set of exposed points in terms of rotund points and non-smooth *** long as we have Banach spaces each time＂bigger＂,we consider sets of non-smooth points each time＂smaller＂.

关键词： Exposed point exposed face rotund point smooth point

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