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Secondary seed dispersal by dung beetles in an Amazonian forest fragment of Colombia:influence of dung type and edge effect

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Integrative Zoology 2011年第4期6卷 399-408页

作者： carolina SANTOS-HEREDIA Ellen ANDRESEN Pablo STEVENSON Department of Biological Sciences University of the AndesBogotaColombia Center for Ecosystem Research at the National Autonomous University of Mexico MoreliaMexico

Seeds of many plant species are secondarily dispersed by dung beetles,but the outcome of this interaction is highly *** is known about how certain anthropogenic disturbances affect this plant-animal *** aims of this study were to assess the effect of dung type on secondary dispersal by dung beetles in a forest fragment,and to determine whether this interaction is affected by edge *** pitfall traps,we captured dung beetles attracted to dung of 2 frugivorous mammals:woolly monkeys and howler *** found differences between both dung beetle assemblages,but these differences were not consistent in *** seeds surrounded by both dung types,we carried out a field experiment using seeds of 2 plant *** found that the probability of secondary dispersal by dung beetles was higher for seeds placed in woolly monkey ***,we carried out a field experiment using plastic beads as seed mimics to assess edge *** found that secondary seed dispersal by dung beetles was negatively affected by *** disruption of plant-animal interactions along anthropogenic forest edges could have long-term negative effects on forest dynamics by affecting processes of regeneration.

关键词： fragmentation plant-animal interaction Scarabaeidae seed fate

Changes in air pollution during COVID-19 lockdown in Spain:A multi-city study

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Journal of Environmental Sciences 2021年第3期33卷 16-26页

作者： Álvaro Briz-Redón carolina Belenguer-Sapiña Ángel Serrano-Aroca Statistics Office City Council of Valenciac/Arquebisbe Mayoral246002 ValenciaValenciaSpain Department of Analytical Chemistry Faculty of ChemistryUniversity of Valenciac/Doctor Moliner 5046100 BurjassotValenciaSpain Centro de Investigación Traslacional San Alberto Magno Universidad Católica de Valencia San Vicente Mártirc/Guillem de Castro 9446001 ValenciaValenciaSpain

The COVID-19 pandemic has escalated into one of the largest crises of the 21 st *** new SARS-CoV-2 coronavirus,responsible for COVID-19,has spread rapidly all around the *** Spanish Government was forced to declare a nationwide lockdown in view of the rapidly spreading virus and high mortality rate in the *** study investigated the impact of short-term lockdown during the period from March 15th to April 12th 2020 on the atmospheric levels of CO,SO_(2),PM_(10),O_(3),and NO_(2)over 11 representative Spanish *** possible influence of several meteorological factors(temperature,precipitation,wind,sunlight hours,minimum and maximum pressure)on the pollutants'levels were also *** results obtained show that the 4-week lockdown had significant impact on reducing the atmospheric levels of NO_(2)in all cities except for the small city of Santander as well as CO,SO_(2),and PM_(10)in some cities,but resulted in increase of O_(3)level.

关键词： COVID-19 Lockdown Air quality Pollution Meteorology

Channel adaptive rate control for energy optimization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 82-88页

作者： BLANCH carolina POLLIN Sofie LAFRUIT Gauthier EBERLE Wolfgang Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050Belgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050 Belgium Department of Electrical EngineeringK.U.LeuvenESAT/INSYSBelgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium

Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications.

关键词： Rate control, Channel condition, Communication energy

A POSTERIORI ERROR ANALYSIS OF A FULLY-MIXED FINITE ELEMENT METHOD FOR A TWO-DIMENSIONAL FLUID-SOLID INTERACTION PROBLEM

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Journal of Computational Mathematics 2015年第6期33卷 606-641页

作者： carolina Dominguez Gabriel N. Gatica salim meddahi Instituto de Ciencias Fisicas y Matemdticas facultad de ciencias universidad austral de chile Avenida Eduardo Morales Miranda - Campus isla teja valdivia chile CI2 MA and Departamento de Ingenieria Matematica Universidad de concapcion casilla 160 concepcion chile Departamento de Matemdticas Facultad de ciencias universidad de oiede calvo satela s/n oviedo espana

In this paper we develop an a posteriori error analysis of a fully-mixed finite element method for a fluid-solid interaction problem in 2D. The media are governed by the elas-todynamic and acoustic equations in time-harmonic regime, respectively, the transmission conditions are given by the equilibrium of forces and the equality of the corresponding normal displacements, and the fluid is supposed to occupy an annular region surrounding the solid, so that a Robin boundary condition imitating the behavior of the sommerfeld condition is imposed on its exterior boundary. Dual-mixed approaches are applied in both domains, and the governing equations are employed to eliminate the displacenent a of the solid and the pressure p of the fluid. In addition, since both transmission conditions become essential, they are enforced weakly by means of two suitable lahrange multipliers The unknowns of the solid and the fluid are then approximated by a conforming galerkin scheme defined in terms of PEERS elements in the solid, Raviart-Thomas of lowest order in the fluid, and continuous piecewise linear functions on the boundary, As the main con-tribution of this work, we derive a reliable and efficient residual-based a posteriori error estimator for the aforedescribed coupled problem. Some numerical results confirming the properties of the estimator are also reported.

关键词： Mixed finite elements Helmholtz equation Elastodynamic equation A poste- riori error analysis

FAST SPECTRAL GALERKIN METHOD FOR LOGARITHMIC SINGULAR EQUATIONS ON A SEGMENT＊

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Journal of Computational Mathematics 2018年第1期36卷 128-158页

作者： Carlos Jerez-Hanckes Serge Nicaise carolina Urzua-Torres School of Engineering Pontificia Universidad Catolica de Chile 782-0436 Santiago Chile. LAMAV Universite de Valenciennes and CNRS 59313 Valenciennes France. Seminar for Applied Mathematics ETH Zurich Raemistrasse 101 8092 Zurich Switzerland.

We present a fast Galerkin spectral method to solve logarithmic singular equations on segments. The proposed method uses weighted first-kind Chebyshev polynomials. Conver- gence rates of several orders are obtained for fractional Sobolev spaces H^-1/2 （or H00^-l/2）. Main tools are the approximation properties of the discretization basis, the construction of a suitable Hilbert scale for weighted L2-spaces and local regularity estimates. Numerical experiments are provided to validate our claims,

关键词： Screen problems Boundary integral operators Spectral methods.

A conserved arbuscular mycorrhizal fungal core-species community colonizes potato roots in the Andes

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Fungal Diversity 2016年第2期77卷 317-333页

作者： carolina Senés-Guerrero Arthur Schüßler Department of Biology GeneticsLudwig-Maximilians UniversityGrosshaderner Str.482152 PlaneggMartinsriedGermany

Plant-symbiotic arbuscular mycorrhizal fungi(AMF)are of high global ecological and economic importance,but describing environmental communities of AMF at the species level remains a challenge,despite the need to understand AMF-plant preferences and to apply AMF in sustainable ***,the potato-associated AMF species community composition was assessed for three Andean countries along an altitudinal gradient and at different plant stages,by using 454 GS-FLX+sequencing of a 760 bp LSU rRNA gene PCR *** methods were compared:defining OTUs based on a simple sequence similarity threshold,or affiliating reference sequences to species based on a high throughput phylogenetic annotation approach using an evolutionary placement algorithm(EPA).The EPA-based approach was not only more precise,but also fundamental to robustly unveil the AMF species community *** principal advantage of this approach was also demonstrated by using artificially constructed datasets based on validated public database *** affiliation of sequence reads to species using phylogenetic annotation revealed a surprisingly conserved AMF core-species community structure in Andean potatoes,regardless of different plant stages and environmental *** total,41 species were detected and in some cases more than 25 species were found colonizing an individual root *** species were identified as dominant colonizers,co-occurring with Cetraspora nodosa and certain Claroideoglomus and Rhizophagus species in most potato root samples.

关键词： 454 pyrosequencing Andean ecosystems Arbuscular mycorrhizal fungi species communities DNA based species identification Evolutionary placement algorithm Solanum tuberosum(potato)

Getting started in endoscopic ear surgery

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Journal of Otology 2020年第1期15卷 6-16页

作者： Peter Ryan carolina Wuesthoff Nirmal Patel Department of Otolaryngology and Head and Neck Surgery Royal North Shore HospitalSt LeonardsNSWAustralia Kolling Deafness Research Centre Macquarie University and University of SydneyNSWAustralia cSydney Endoscopic Ear Surgery Research Group Department of Otolaryngology-Head&Neck SurgeryFaculty of Medicine and Health SciencesMacquarie UniversitySydneyAustralia Discipline of Surgery Sydney Medical SchoolUniversity of SydneyAustralia

Endoscopic ear surgery(EES) is an exciting, rapidly developing and innovative field of otologic *** and conceptually, EES is a significant departure from traditional microscopic transcanal approaches to the middle ear and canal that has shown very positive results with respect to patient outcomes. This review serves as a primer for the otologist and otology resident embarking on EES and discusses the theory surrounding the learning process, the optical chain for endoscopic surgery as well as other important underlying principles.

关键词： Endoscopic Endoscopic Ear Surgery Optical Chain

Biosynthesis of Callose and Cellulose by Detergent Extracts of Tobacco Cell Membranes and Quantification of the Polymers Synthesized in vitro

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Journal of Integrative Plant Biology 2010年第2期52卷 221-233页

作者： carolina Cifuentes Vincent Bulone Anne Mie C.Emons Laboratory of Plant Cell Biology Wageningen University Division of Glycoscience School of BiotechnologyRoyal Institute of TechnologyAlbaNova University Center Department of Biomolecular Systems FOM Institute for Atomic and Molecular Physics

The conditions that favor the in vitro synthesis of cellulose from tobacco BY-2 cell extracts were determined. The procedure leading to the highest yield of cellulose consisted of incubating digitonin extracts of membranes from 11-day-old tobacco BY-2 cells in the presence of 1 mM UDP-glucose, 8 mM Ca^2＋ and 8 mM Mg^2＋. Under these conditions, up to nearly 40% of the polysaccharides synthesized in vitro corresponded to cellulose, the other polymer synthesized being callose. Transmission electron microscopy analysis revealed the occurrence of two types of structures in the synthetic reactions. The first type consisted of small aggregates with a diameter between 3 and 5 nm that associated to form fibrillar strings of a maximum length of 400 nm. These structures were sensitive to the acetic/nitric acid treatment of Updegraff and corresponded to callose. The second type of structures was resistant to the Updegraff reagent and corresponded to straight cellulose microfibrils of 2-3 nm in diameter and 200 nm to up to 5 μm in length. In vitro reactions performed on electron microscopy grids indicated that the minimal rate of microfibril elongation in vitro is 120 nm/min. Measurements of retardance by liquid crystal polarization microscopy as a function of time showed that small groups of microfibrils increased in retardance by up to 0.047 nm/min per pixel, confirming the formation of organized structures.

关键词： Biosynthesis of Callose and Cellulose by Detergent Extracts of Tobacco Cell Membranes and Quantification of the Polymers Synthesized in vitro

Scavenging of reactive oxygen and nitrogen species with nanomaterials

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Nano Research 2018年第10期11卷 4955-4984页

作者： carolina A. Ferreira Dalong Ni Zachary T. Rosenkrans Weibo Cai Department of Radiology University of Wisconsin-Madison Madison W153705 USA

Reactive oxygen and nitrogen species （RONS） are essential for normal physiological processes and play important roles in cell signaling, immunity, and tissue homeostasis. However, excess radical species are implicated in the development and augmented pathogenesis of various diseases. Several antioxidants may restore the chemical balance, but their use is limited by disappointing results of clinical trials. Nanoparticles are an attractive therapeutic alternative because they can change the biodistribution profile of antioxidants, and possess intrinsic ability to scavenge RONS. Herein, we review the types of RONS, how they are implicated in several diseases, and the types of nanoparticles with inherent antioxidant capability, their mechanisms of action, and their biological applications.

关键词： mnanomaterials reactive oxygen species(ROS) reactive nitrogen species ROS scavenging antioxidant nanoparticles