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Influence of local and landscape environmental factors on alpha and beta diversity of macroinvertebrates in Andean rivers

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Journal of Mountain Science 2023年第9期20卷 2487-2501页

作者： diaz-ROJAS Camila A PEDROZA-RAMOS Adriana X BARRERA-HERRERA July A ROA-FUENTES Camilo A Ecology Unit in Aquatic Systems Research Group Pedagogical and Technological University of ColombiaUPTCAvenida Central del Norte 39-115TunjaBoyacáColombia

Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of landscape-scale variables have been evaluated to a lesser *** objective of this study was to describe the patterns of alpha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their relationship with local and landscape environmental variation.A stratified random sampling of macroinvertebrates was carried out at 40 sites(comprising an altitudinal range of between 500 and 2900 m.a.s.l.),local and landscape variables were *** results showed that the variation of alpha diversity was influenced by local and landscape variables,which are directly and indirectly related to the contribution of sediments,substrate composition and flow velocity,providing a heterogeneity of *** beta diversity was explained by the combined effect of local and landscape *** the beta diversity phenomena,turnover was predominant while nestedness presented a minor contribution and both were explained in greater proportion by local descriptors and some landscape variables,specifically those of a geomorphological *** results concur with the view of an environmental and spatial hierarchy within the river habitat and highlight the influence of multiple scales on macroinvertebrate *** above suggests that both local and landscape scales must necessarily be considered for environmental management and the conservation of Andean lotic ecosystems.

关键词： Andean lotic systems Andean agroecosystems Instream habitat landcover Turnover Nestedness

Reducing bacterial adhesion to titanium surfaces using low intensity alternating electrical pulses

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World Journal of Orthopedics 2022年第6期13卷 578-586页

作者： Marti Bernaus Jordi Guillem-Marti Adrian Bermúdez-Castel Jose Antonio calero Diego Torres Margarita Veloso lluís Font-Vizcarra Department of Orthopedics and Traumatology Osteoarticular Infection UnitHospital Universitari Mutua TerrassaTerrassa 08221Spain Department of Materials Science and Metallurgical Engineering Universitat Politecnica de CatalunyaBarcelona 08930Spain Barcelona Research Center in Multiscale Science and Engineering Universitat Politecnica de CatalunyaBarcelona 08930Spain Innovative Minds S.L.Terrassa 08224Spain AMES PM Tech Center Sant Vicençdels Horts 08980Spain

BACKGROUND Orthopedic implant-related infection remains one of the most serious complications after orthopedic *** recent years,there has been an increased scientific interest to improve prevention and treatment ***,many of these strategies have focused on chemical *** To analyze the effect of alternating current electrical fields on bacterial adherence to titanium *** Staphylococcus aureus(***)and Escherichia coli(***)were exposed to 6.5 V electrical currents at different frequencies:0.5 Hz,0.1 Hz,and 0.05 *** exposure,a bacterial count was then performed and compared to the control *** variables registered included the presence of electrocoagulation of the medium,electrode oxidation and/or corrosion,and changes in pH of the *** The most effective electrical model for reducing *** adhesion was 6.5 V alternating current at 0.05 Hz achieving a 90%adhesion reduction *** ***,the 0.05 Hz frequency model also showed the most effective results with a 53%adhesion reduction rate,although these were significantly lower than *** adhesion reduction rates were observed for *** and *** in the studied ***,the presence of electrode oxidation makes us presume these conditions are not optimal for in vivo *** Although our findings suggest electrical currents may be useful in preventing bacterial adhesion to metal surfaces,further research using other electrical conditions must be examined to consider their use for in vivo trials.

关键词： Electrical fields Bacterial adhesion Orthopedic infection Titanium Metal surfaces

Phenomenological Based Soft Sensor for Online Estimation of Slurry Rheological Properties

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International Journal of Automation and computing 2019年第5期16卷 696-706页

作者： Jenny l.diaz C. Diego A.Munoz Hernan Alvarez Research Group of Dynamic Processes Universidad Nacional de Colombia-Sede MedellínFacultad de Minas.Cra 80Medellín 65-223Colombia Mathematical Optimization of Processes Centro de Ciencia BásicaUniversidad Pontificia BolivarianaCircular 1Medellín 70-01Colombia

This work proposes a soft sensor based on a phenomenological model for online estimation of the density and viscosity of a slurry flowing through a pipe-and-fittings assembly(PFA). The model is developed considering the conservation principle applied to mass and momentum transfer and considering frictional energy losses to include the variables directly affecting slurry properties. A reported proposal for state observers with unknown inputs is used to develop the first block of the observer structure. The second block is constructed with two options for evaluating slurry viscosity, generating two possible estimator structures, which are tested using real data. A comparison between them indicates different uses and capabilities according to available process information.

关键词： Soft sensor phenomenological based semi-physical model non-Newtonian fluids unknown input observer slurry flow

Hilbert Space of Probability Density Functions Based on Aitchison Geometry

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1175-1182页

作者： J.J.EGOZCUE J.l.diaz-BARRERO V.PAWlOWSKY-GlAHN Applied Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 1-3C208034BarcelonaSpain Applied Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 13C208034BarcelonaSpain Informatics and Applied Mathematics Universitat de GironaCampus MontiliviP417071GironaSpain

The set of probability functions is a convex subset of l1 and it does not have a linear space structure when using ordinary sum and multiplication by real constants. Moreover, difficulties arise when dealing with distances between densities. The crucial point is that usual distances are not invariant under relevant transformations of densities. To overcome these limitations, Aitchison＇s ideas on compositional data analysis are used, generalizing perturbation and power transformation, as well as the Aitchison inner product, to operations on probability density functions with support on a finite interval. With these operations at hand, it is shown that the set of bounded probability density functions on finite intervals is a pre-Hilbert space. A Hilbert space of densities, whose logarithm is square-integrable, is obtained as the natural completion of the pre-Hilbert space.

关键词： Bayes' theorem Fourier coefficients Haar basis Aitchison distance Simplex least squares approximation

Changes in Olsen P in Relation to P Balance in Contrasting Agricultural Soils

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Pedosphere 2016年第5期26卷 636-642页

作者： Isabel diaz Jose TORRENT Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos Escuela Tdcnica Superior de Ingeniería Agronómica(ETSIA)Universidad de SevillaCtra de Utrera km 141013 Sevilla(Spain) Departamento de Agronomia Universidad de CordobaEdificio C4Campus de Rabanales14071 Cordoba(Spain)

Maintaining soil phosphorus(P) at adequate levels for plant growth requires assessing how the long-term P balance(viz., the difference between P inputs and outputs) results in changes in soil test P. The hypothesis that routinely measured soil properties can help predict the conversion factor of P balance into Olsen P was tested at 39 sites in agricultural areas of the Mediterranean region in Spain. A set of soil samples from each site was analyzed for Olsen P, inorganic P(P extracted using 0.5 mol l^(-1) H_2SO_4), pseudototal P(P extracted using 0.5 mol l^(-1) H_2SO_4 following ignition at 550℃), and organic P(the difference between pseudototal P and inorganic P). Organic and Olsen P were uncorrelated in most of the 39 soil sets, which suggests that organic P content changed little with P inputs and outputs. The slopes of the regression lines of Olsen P against pseudototal and inorganic P, which were used as two different measures of the conversion factor, ranged widely(from 0.03 to 0.25 approximately), with their average values(about 0.10) being similar to those found in long-term experiments conducted in temperate areas. Neither conversion factor was significantly correlated with any routinely measured soil property; however, the conversion factor for inorganic P was significantly lower for calcareous soils than for noncalcareous soils. Our negative results suggest the need to isolate the influence of soil properties from that of management systems and environmental factors relating to P dynamics in future studies.

关键词：磷素平衡农业土壤 H2SO4 土壤性质土壤测试转换因子常规测量石灰性土壤

Inversion of electrical mobility measurements using bipolar or unipolar chargers for the arbitrary distribution of channels

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Particuology 2015年第3期13卷 114-123页

作者： M.Domat F.E.Kruis N.l.Azong-Wara J.M.Fernandez-diaz Department of Physics University of OviedoC/Calvo Sotelos/nE-33007 OviedoSpain Institute of Technology for Nanostructures(NST) and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenBismarckstr.81D-47057 DuisburgGermany

The inversion of the particle size distribution from electrical mobility measurements is analyzed. Three different methods are adapted for a dot-matrix approach to the problem, especially for non-square or singular matrices, and applied to electrical mobility measurements from fixed or scanning voltages. Mul- tiply charged particles, diffusion losses, arbitrary voltage steps and noise were considered, which results in non-adjoining and overlapping transfer functions. The individual contribution of the transfer func- tions in each size interval was geometrically estimated, which requires only its characteristic mobilities. The methodology is applied to mobility measurements from particles charged with unipolar and bipolar chargers. However, the method can be extrapolated to any charging method with a defined charge distribution, and retrieval of the singly charged particle distribution and mean charge from a tandem differential mobility analysis configuration was successfully demonstrated.

关键词： Tandem differential mobility analysisInverse problemRegularization methodsSize distributionTransfer functionUnipolar charger

Solid-state synthesis of lnOCl/ln_2O_3(ln=Eu, Nd) by using chitosan and PS-co-P4VP as polymeric supports

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Journal of Rare Earths 2018年第12期36卷 1326-1332页

作者： C.diaz D.Carrillo R.de la Campa A.Presa Soto M.l.Valenzuela Departamento de Quimica Facultad de Quimica Universidad de Chile Departamento de Quimica Organica e Inorganica (IUQOEM) Facultad de Quimica Universidad de Oviedo Universidad Autonoma de Chile Facultad de Ingenieria Instituto de Ciendas Quimicas Aplicadas Inorganic Chemistry and Molecular Material Center

A series of lanthanide materials of type lnOCl or ln2O3(ln = Eu, Nd) were successfully prepared via a convenient and straightforward two-step procedure. Firstly, and by using chitosan and PS-co-P4 VP as polymeric supports, macromolecular complexes of type chitosan ·lnCl3and PS-co-P4 VP·lnCl3 were prepared. These macro molecular complexes were treated in solid state at 800 ℃ under air, leading to the corresponding lnOCl or ln2O3materials(ln = Eu, Nd) with moderate to good yields. The nature of the asprepared lanthanide materials(lnOCl and/or ln2O3) is strongly influenced by the polymeric template(i.e.,chitosan or PS-co-P4 VP), the lanthanide salt precursor, and the polymer/lanthanide molar ratio. Thus, when chitosan · EuCl3and PS-co-P4 VP·EuCl3are used as macromolecular precursors, a mixture of crystalline phases of both EuOCl and Eu2O3are obtained. However, when chitosan· NdCl3and PS-co-P4 VP· NdCl3are used, a sole pure crystalline phase of NdOCl is obtained. The nano structured lanthanide materials were characterized by means of XRD(X-ray diffraction of powder), SEM, EDS, TEM, and HRTEM. The luminescent spectra of the asprepared EuOCI/Eu2O3mixture materials show an emission pattern whose intensity is strongly influenced by the nature of the polymeric precursor, as well as on the metal/polymer molar ratios.

关键词： EuOCl/Eu_2O_3 NdOCl Solventless method luminescence lanthanides Rare earths

Analytical Solution for Waves Propagation in Heterogeneous Acoustic/Porous Media. Part I: The 2D Case

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Communications in Computational Physics 2010年第3期7卷 171-194页

作者： Julien diaz Abdelaaziz Ezziani Project-team Magique-3D INRIA Bordeaux Sud-Ouest lMA Pau CNRS UMR 5142I.P.R.A-Universit´e de Pau et des Pays de l’Adouravenue de l’Universit´e BP 1155-64013 PAU CEDEXFrance

Thanks to the Cagniard-de Hoop’s method we derive the solution to theproblem of wave propagation in an infinite bilayered acoustic/poroelastic media, wherethe poroelastic layer is modelled by the biphasic Biot’s model. This first part is dedi-cated to solution to the two-dimensional problem. We illustrate the properties of thesolution, which will be used to validate a numerical code.

关键词： Biot’s model poroelastic waves acoustic waves acoustic/poroelastic coupling ana-lytical solution Cagniard-de Hoop’s technique 2D

Search for the doubly heavy baryons Ωbc0 and Ξbc0 decaying to Λc+π- and Ξc+π-

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Chinese Physics C 2021年第9期45卷 14-25页

作者： R.Aaij C.Abellán Beteta T.Ackernley B.Adeva M.Adinolfi H.Afsharnia C.A.Aidala S.Aiola Z.Ajaltouni S.Akar J.Albrecht F.Alessio M.Alexander A.Alfonso Albero Z.Aliouche G.Alkhazov P.Alvarez Cartelle S.Amato Y.Amhis l.An l.Anderlini A.Andreianov M.Andreotti F.Archilli A.Artamonov M.Artuso K.Arzymatov E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmayer J.J.Back P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista leite R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov J.M.Basels G.Bassi B.Batsukh A.Battig A.Bay M.Becker F.Bedeschi I.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Belyaev G.Bencivenni E.Ben-Haim A.Berezhnoy *** D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko S.Bhasin J.Bhom l.Bian M.S.Bieker S.Bifani P.Billoir M.Birch F.C.R.Bishop A.Bitadze A.Bizzeti M.Bj?rn M.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldyrev A.Bondar N.Bondar S.Borghi M.Borisyak M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer C.Bozzi M.J.Bradley S.Braun A.Brea Rodriguez M.Brodski J.Brodzicka A.Brossa Gonzalo D.Brundu A.Buonaura C.Burr A.Bursche A.Butkevich J.S.Butter J.Buytaert W.Byczynski S.Cadeddu H.Cai R.Calabrese l.Calefice l.calero diaz S.Cali R.Calladine M.Calvi M.Calvo Gomez P.Camargo Magalhaes A.Camboni P.Campana A.F.Campoverde Quezada S.Capelli l.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini I.Carli P.Carniti l.Carus K.Carvalho Akiba A.Casais Vidal G.Casse M.Cattaneo G.Cavallero S.Celani J.Cerasoli A.J.Chadwick M.G.Chapman M.Charles Ph.Charpentier G.Chatzikonstantinidis C.A.Chavez Barajas M.Chefdeville C.Chen S.Chen A.Chernov V.Chobanova S.Cholak M.Chrzaszcz A.Chubykin V.Chulikov P.Ciambrone M.F.Cicala X.Cid Vidal G.Ciezarek P.E.l.Clarke M.Clemencic H.V.Cliff J.Closier J.l.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cogneras l.Cojocariu P.Collins T.Colombo l.Congedo A.Contu N.Cooke G.Coombs G.Corti C.M.Costa Sobral B.Couturier D.C.Craik J.Crkovská M.Cruz Torres R.Currie C.l.Da Silva E.Dall'Occo J.Dalseno C.D'Amb University of Edinburgh Horia Hulubei National Institute of Physics and Nuclear Engineering INFN Sezione di Bari Università di Bari los Alamos National laboratory (lANl) Van Swinderen Institute University of Groningen Universiteit Maastricht AGH-University of Science and Technology Faculty of Physics and Applied Computer Science Université Clermont Auvergne Università di Cagliari Institute for Nuclear Research of the National Academy of Sciences (KINR) School of Physics University College Dublin NSC Kharkiv Institute of Physics and Technology (NSC KIPT) INFN Sezione di Perugia STFC Rutherford Appleton laboratory School of Physics and Astronomy Monash University Novosibirsk State University CNRS/IN2P3 Department of Physics and Astronomy Uppsala University Università di Genova School of Physics State Key laboratory of Nuclear Physics and Technology Peking University National Center for Nuclear Research (NCBJ) Università di Roma Tor Vergata Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio) Universidade Federal do Triangulo Mineiro (UFTM) Institute of Particle Physics lPC Central China Normal University Hangzhou Institute for Advanced Study UCAS Instituto de Fisica Corpuscular Centro Mixto Universidad de Valencia-CSIC Nikhef National Institute for Subatomic Physics and VU University Amsterdam National Research Tomsk Polytechnic University AGH-University of Science and Technology Faculty of Computer Science Electronics and Telecommunications University of Michigan Università di Siena Università di Padova Scuola Normale Superiore National Research Centre Kurchatov Institute Università degli Studi di Milano MSU-Iligan Institute of Technology (MSU-IIT) Università di Firenze INFN Sezione di Roma la Sapienza Institut für Physik Universit?t Rostock INFN Sezione di Milano Departamento de Fisica Universidad Nacional de Colombia Universit?t Bonn-Helmholtz-Institut für Strahlen und Kernphysik Hanoi University of Science Università di Pisa P.N. lebedev Physical Institute Russian Academy of Science (lPI RAS) Università

The first search for the doubly heavy Ωbc0baryon and a search for the Ξbc0baryon are performed using pp collision data collected via the lHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 *** baryons are reconstructed via their decays to ∧c+π-andΞc+π-.No significant excess is found for invariant masses between 6700 and 7300 MeV/c2,in a rapidity range from2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/*** limits are set on the ratio of the Ωbc0andΞbc0production cross-section times the branching fraction to ∧c+π-（Ξc+π-） relative to that of the ∧b0（Ξb0） baryon,for different lifetime hypotheses,at 95% confidence *** upper limits range from 0.5×10-4to 2.5×10-4for theΩbc0→∧c+π-(Ξbc0→∧c+π-) decay,and from 1.4×10-3to 6.9×10-3for the Ωbc0→Ξc+π-(Ξbc0→Ξc+π-) decay,depending on the considered mass and lifetime of the Ωbc0(Ξbc0) baryon.

关键词： B physics quarkonium spectroscopy heavy quark production