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Natural Resources 2014年第15期5卷 958-967页

作者： Juliana Guimaraes Gerola juan ricardo rocha Stella Cristiani Goncalves Matoso Leandro Dias da Silva Agricultural Engineering Federal Institute of RondoniaCampus Colorado do OesteColorado do OesteBrazil Biodiversity and Biotechnology of the Amazon at the BIONORTE Network ManausBrazil Soil Science Federal Institute of RondoniaCampus Colorado do OesteColorado do OesteBrazil Soil Laboratory Federal Institute of RondoniaCampus Colorado do OesteColorado do OesteBrazil

Sandy soils have limitations for growing plants. In general, they have low fertility, high toxic aluminum content and low organic matter. The organic matter is responsible for most of the cation exchange capacity of these soils. Added to this, the low clay content and the structure of these soils with large volumes of macropores, determine their low water retention. An alternative is the incorporation of organic waste combined with the practice of liming. Thus, the aim of this study was to evaluate the contribution of the incorporation of poultry litter and limestone in the fertility of sandy soils in the Brazilian Amazon. The experiment was conducted in Colorado do Oeste, RO, on a Quartzipsamment in a completely randomized block design in a 4 × 4 × 2 factorial scheme, corresponding to four doses of poultry litter (0, 5, 10 and 15 mg·ha-1), its incorporation for four times (0, 75, 110 and 145 days) in the presence and absence of 2 mg·ha-1 of limestone, with six replications. The incorporation of 15 mg·ha-1 of poultry litter combined with 2 mg·ha-1 of limestone for 75 days after the merger raises several components of Quartzipsamment fertility, mainly being the availability of phosphorus.

关键词： Quartzipsamments Organic Waste Liming

Historical relationships of areas of endemism of the Brazilian Atlantic rain forest： a cladistic biogeographic analysis of harvestman taxa （Arachnida： Opiliones）

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Current Zoology 2017年第5期63卷 525-535页

作者： Marcio B. DASILVA ricardo PINTO-DA-rocha juan J. MORRONE Departamento de Sistematica e Ecologia CCEN Universidade Federal da Paraiba Cidade Universitaria Joao Pessoa PB Brazil Departamento de Zoologia Instituto de Biociencias Universidade de Sao Paulo Sao Paulo SP Brazil Museo de Zoologia "Alfonso L. Herrera" Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autdnoma de Mexice (UNAM) 04510 Mexico City Mexico

Based on a cladistic biogeographic analysis of 6 species-level phylogenies of harvestman taxa, wesearched for congruence in the historical relationships of 12 areas of endemism of the BrazilianAtlantic Rain Forest. We constructed general area cladograms using Primary Brooks ParsimonyAnaJysis （BPA）, BPA of nodes, and paralogy-free subtree analysis. These analyses resulted in 6general area cladograms, that allow to infer a general pattern of the relationships among areas ofendemism from the Brazilian Atlantic Rain Forest. Northern areas resulted related basally showingmain disjunctions at the Doce River Valley and Todos os Santos Bay/S^o Francisco River *** remaining areas of endemism were included in a southern and a southeastern block, sepa-rated by the Ribeira do Iguape Valley. Incongruence Length Differences tests showed no significantincongruence among the resulting cladograms and other matrix partitions. We concluded that tec-tonism and ancient marine transgressions were the probable processes responsible for the maindisjunctions, whereas Neogene refugia seem to have caused the more recent disjunctions. Thegeneral pattern and redundancy in area relationships suggest a model of main reiterative barriersin diversification at multiple times for the evolution of the Atlantic Rain Forest. The renewal of cla-distic biogeography and the search for common biogeographic patterns are discussed.

关键词： dispersal, historical biogeography, Mata Atlantica, speciation, vicariance.

Denitrification-nitrification process in permeable coastal sediments:An investigation on the effect of salinity and nitrate availability using flow-through reactors

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Acta Oceanologica Sinica 2021年第9期40卷 1-12页

作者： Shan Jiang Mark Kavanagh juan Severino Pino Ibanhez Carlos rocha State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China School of Natural Sciences Trinity College DublinDublin 2Ireland Trinity Centre for the Environment School of Natural SciencesTrinity College DublinDublin 2Ireland Instituto de Investigacions Marinas Consejo Superior de Investigaciones CientiTicasVigo 36208Spain

Permeable coastal sediments act as a reactive node in the littoral zone,transforming nutrients via a wide range of biogeochemical *** rates are controlled by abiotic factors,e.g.,salinity,temperature or solute ***,a series of incubation experiments,using flow-through reactors,were conducted to simulate the biogeochemical cycling of nitrate (NO_(3)^(-)) and phosphorus(P)in permeable sediments under different NO_(3)^(-) availability conditions(factor I)along a salinity gradient(admixture of river and seawater,factor Ⅱ).In an oligotrophic scenario,i.e.,unamended NO_(3)^(-) concentrations in both river and seawater,sediments acted as a permanent net source of NO_(3)^(-) to the water *** peak production rate occurred at an intermediate salinity(20).IncreasingNO_(3)^(-) availability in river water significantly enhanced netNO_(3)^(-) removal rates within the salinity range of 0 to 30,likely via the denitrification pathway based on the sediment microbiota *** this scenario,the most active removal was obtained at salinity of *** both river and seawater were spiked with NO_(3)^(-),the highest removal rate switched to the highest salinity(36).It suggests the salinity preference of the NO_(3)^(-) removal pathway by local denitrifiers(e.g.,Bacillus and Paracoccus)and that NO_(3)^(-) removal in coastal sediments can be significantly constrained by the dilution related NO_(3)^(-) *** with the obtained variation for NO_(3)^(-) reactions,permeable sediments acted as a sink of soluble reactive P in all treatments,regardless of salinity and NO_(3)^(-) input concentrations,indicating a possibility of P-deficiency for coastal water from the intensive cycling in permeable ***,the net production of dissolved organic carbon(DOC)in all treatments was positively correlated with the measured NO_(3)^(-) reaction rates,indicating that the DOC supply may not be the key factor for NO_(3)^(-) removal rates due

关键词： NO_(3)^(-)production and removal flow-through reactors salinity stable isotopes permeable sediments

Developing and validating a nestling photographic aging guide for cavity-nesting birds: an example with the European Bee-eater(Merops apiaster)

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Avian Research 2020年第1期11卷 57-64页

作者： Joana S.Costa Afonso D.rocha ricardo A.Correia Jose A.Alves Department of Biology&CESAM University of AveiroCampus Universitario de Santiago3810-193 AveiroPortugal Institute of Biological and Health Sciences(ICBS) Federal University of AlagoasMaceioALBrazil University of Iceland South Iceland Research CentreLindarbraut 4840 LaugarvatnIceland

Background: Accurate estimation of nestlings’ age is essential in avian demography studies as well as in population ecology and conservation. For example, it can be useful for synchronizing nest visits with events of particular interest, such as the age at which young can be safely ringed, or in choosing the best period to attain the most accurate calculation of laying or hatching ***: We constructed a photographic guide for aging European Bee-eaters(Merops apiaster) nestlings to 3-day age classes and evaluated the aging method by performing a validation exercise with several observers with no previous experience in aging bee-eater ***: The aging guide for bee-eater nestlings allowed estimating age to within 3 days with an average accuracy of 0.85. We found the optimal period for aging nestlings was between days 13-18(with accuracy between 0.94 and 0.99), during which the status of feather development was more easily distinguishable from the preceding and subsequent age classes. During the first 3 days after hatching, nestlings could also be aged with high accuracy(0.93). The small size of the nestling in relation to the eggs and the nestling’s inability to raise its head during these first days allowed for good discrimination from the subsequent age class. Between days 25 and 28, nestlings were correctly aged in only half of assignments(0.55 sensitivity) and nestlings belonging to class 7(days 7-9) were the least correctly identified(0.38 sensitivity). However, by visiting the nests at 12 days intervals it is possible to achieve the highest accuracy in age estimation with the smallest disturbance and logistic ***: This study highlighted how indirect methods and a simple protocol can be established and employed to quickly estimate nestling age in cases where handling nestlings is challenging or impossible, while minimizing disturbance in and around the nest.

关键词： Age estimation Chick development Feather growth Image guide Nest visit Plumage colour

Collaborative learning via social computing

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 265-282页

作者： ricardo S.ALONSO Javier PRIETO óscar GARCíA juan M.CORCHADO BISITE Research Group University of Salamanca

Educational innovation is a field that has been greatly enriched by using technology in its processes, resulting in a learning model where information comes from numerous sources and collaboration takes place among multiple students. One attractive challenge within educational innovation is the design of collaborative learning activities from the social computing point of view, where collaboration is not limited to student-to-student relationships, but includes student-to-machine interactions. At the same time, there is a great lack of tools that give support to the whole learning process and are not restricted to specific aspects of the educational task. In this paper, we present and evaluate context-aware framework for collaborative learning applications(CAFCLA) as a solution to these problems. CAFCLA is a flexible framework that covers the entire process of developing collaborative learning activities, taking advantage of contextual information and social interactions. Its application in the experimental case study of a collaborative WebQuest within a museum has shown that, among other benefits, the use of social computing improves the learning process, fosters collaboration, enhances relationships, and increases engagement.

关键词： Context-awareness Collaborative learning Social computing Virtual organizations Wireless sensor networks Real time location system

Intelligent collision risk detection in medium-sized cities of developing countries,using naturalistic driving:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 912-929页

作者： juan Jose Paredes Santiago Felipe Yepes ricardo Salazar-Cabrera Alvaro Pachon dela Cruz juan Manuel Madrid Molina Telematics Engineering Research Group(GIT) Telematics DepartmentUniversidad Del CaucaPopayanColombia Information Technology and Telecommunications Research Group(12T) Universidad IcesiCaliColombia

Traffic accidents are one of the most serious problems worldwide,being one of the leading causes of death and economic loss in the ***-and middle-income countries,mainly their medium-sized cities,are among the most affected by this problem.93%of traffic accidents occur in low and middle-income countries,even though these countries have approximately 60%of the world’s *** occurs mainly because in these types of countries,especially in medium-sized cities(target context),there are no ideal conditions for driving,such as adequate road infrastructure,good condition of vehicles,and rigorous safety *** data analysis techniques including machine learning(ML)have increasingly been used to solve this *** driving(ND)can be applied as a data collection method that provides information on traffic *** commonly uses a vehicle’s kinematic data to detect high-risk driving behaviors that could cause an *** objectives of this document are to present a review of different alternatives that help in data collection and creation of intelligent solutions related to detection of possible traffic accidents,principally using ND;and to propose an intelligent collision risk detection system(ICRDS)for identification of areas with a high probability of TA in the target *** the review,it was possible to analyze and evaluate the devices,variables and algorithms that help characterize a risk event in driving,considering the target *** development of a prototype of an ICRDS for a medium-sized city in a developing country is considered viable,considering the identified components,with the aim of identifying risk events in driving,and areas of high probability of accidents in the city.

关键词： Naturalistic driving Near-crash Traffic accident Vehicle data collection

Sustainable transit vehicle tracking service,using intelligent transportation system services and emerging communication technologies:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第6期7卷 729-747页

作者： ricardo Salazar-Cabrera álvaro Pachón de la Cruz juan Manuel Madrid Molina Telematics Engineering Research Group(GIT) Telematics DepartmentUniversidad del CaucaPopayanColombia Information Technology and Telecommunications Research Group(I2T) ICT DepartmentUniuersidad IcesiCaliColombia

The most salient problems of transit vehicle service in Latin American intermediate cities include:the high number of passengers involved in traffic accidents;traffic congestion caused by transit vehicles,and pollution generated by these vehicles,which increases in high congestion *** improve upon this situation,a research was conducted on the transit vehicle tracking service,which is a basic service for implementing mobility solutions for the aforementioned problems,the most relevant characteristics of this service for the context of Latin American intermediate cities were identified,and an implementation was *** paper presents the four stages of the study:(a)a review of the state-of-the-art of services or systems related to vehicle tracking,including wireless communications technologies,implemented sustainability approaches,usage of special algorithms for efficiency improvement,and the intelligent transportation system(ITS)architecture used as a basis;(b)the process of identifying relevant characteristics of the service for a given context;(c)proposal of an ITS architecture for this service in an intermediate city,its requirements and the suggested technologies;and(d)development of experiments for validating usage of the key suggested *** review allowed to identify the main service characteristics,with regard to vehicle positioning technologies,the recommended wireless communication technology(long range,LoRa),energy consumption considerations,and use of artificial intelligence(AI)to calculate waiting time of users at bus ***,an ITS architecture for the city of Popayan(Colombian city)considering the aforementioned characteristics is proposed,and the experiments related to the use of these technologies are described in detail.

关键词： Transportation engineering Intelligent transportation systems Transit vehicle ITS architecture Tracking Long range

Optimization for performance-based design under seismic demands, including social costs

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 315-328页

作者： Oscar Moller ricardo O.Foschi juan P.Ascheri Marcelo Rubinstein Sergio Grossman Instituto de Mecanica Aplicada y Estructuras (IMAE) Facultad Cs.Ex. Ingenieríay Agrimensura Universidad Nacional de Rosario Riobambay Berutti 2000 Rosario Argentina Civil Engineering Department University of British Columbia 6250 Applied Sciences Lane Vancouver B.C. Canada V6T1Z4

Performance-based design in earthquake engineering is a structural optimization problem that has, as the objective, the determination of design parameters for the minimization of total costs, while at the same time satisfying minimum reliability levels for the specifi ed performance criteria. Total costs include those for construction and structural damage repairs, those associated with non-structural components and the social costs of economic losses, injuries and fatalities. This paper presents a general framework to approach this problem, using a numerical optimization strategy and incorporating the use of neural networks for the evaluation of dynamic responses and the reliability levels achieved for a given set of design parameters. The strategy is applied to an example of a three-story offi ce building. The results show the importance of considering the social costs, and the optimum failure probabilities when minimum reliability constraints are not taken into account.

关键词： earthquake engineering performance-based design optimization reliabiliy social costs

Hlder Norm Estimate for a Hilbert Transform in Hermitean Clifford Analysis

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2289-2300页

作者： ricardo ABREU-BLAYA juan BORY-REYES Fred BRACKX Hennie DE SCHEPPER Frank SOMMEN Facultad de Informática y Matemática Universidad de Holguín Departamento de Matemática Universidad de Oriente Clifford Research Group Faculty of Engineering Ghent University Clifford Research Group Faculty of Sciences Ghent University

A Hilbert transform for H61der continuous circulant （2 × 2） matrix functions, on the d- summable （or fractal） boundary F of a Jordan domain Ω in R2n, has recently been introduced within the framework of Hermitean Clifford analysis. The main goal of the present paper is to estimate the HSlder norm of this Hermitean Hilbert transform. The expression for the upper bound of this norm is given in terms of the HSlder exponents, the diameter of F and a specific d-sum （d 〉 d） of the Whitney decomposition of Ω. The result is shown to include the case of a more standard Hilbert transform for domains with left Ahlfors-David regular boundary.

关键词： Hermitean Clifford analysis Hilbert transform fractal geometry

Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae) as a result of habitat fragmentation

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Plant Diversity 2017年第1期39卷 13-19页

作者： Reyna Maya-Garcia Santiago Arizaga Pablo Cuevas-Reyes juan Manuel Penaloza-Ramirez Victor rocha Ramirez Ken Oyama Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo Mexico Escuela Nacional-de Estudios Superiores Unidad Morelia UNAM Antigua Carretera a Pdtzcuaro 8701 Colonia Ex-Hacienda de SanJose de la Huerta58190 Morelia Michoacan Mexico

Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacfin-Cuicatlan Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency （F15）, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacan-Cuicatlan Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

关键词： MammiUaria pectiniferaNuclear SSRGenetic diversityRecent bottlenecksEffective population size