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Vegetation recovery after fire in mountain grasslands of Argentina

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Journal of Mountain science 2020年第2期17卷 373-383页

作者： Alejandro LOYDI Flavia AFUNK andrés GARCíA Renewable Natural Resources Center of the semi-Arid Zone(CERZOs)–CONICET-UNs Bahia BiancaArgentina Department of Biology Biochemistry and PharmacySouth National UniversityBahfa BiancaArgentina Argentine Institute of Oceanography(IADO) CONICET-UNSBahia BlancaArgentina

Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitable material accumulation. This has led to occasional catastrophic controldemanding fire events, extended for larger areas. The aims of this work are to study vegetation recovery and change after a non-natural fire event in mountain grasslands. The study area is located in the Ventania mountain system, mid-eastern Argentina. We studied vegetation recovery after fire(January 2014) in two different communities: grass-steppes(grasslands) and shrub-steppes(open low shrublands). We measured vegetation cover, species richness and bare ground percentage in burned and unburned areas 1, 4, 8, 11 and 23 months after fire. Vegetation surveys were also performed at the end of the growing season(December) 11 and 23 months after fire. Data were analyzed using regression analysis, ANOVA and multivariate analysis(NMs, PERMANOVA). Both communities increased their vegetation cover at the same rate, without differences between burned and unburned areas after two years. species richness was higher in shrublands and their recovery was alsofaster than in grasslands. Considering functional composition, besides transient changes during the first year after fire, there were no differences in abundance of different functional vegetation groups two years after fire. At the same time, shrublands showed no differences in species composition, while grasslands had a different species composition in burned and unburned plots. Also, burned grassland showed a higher species richness than unburned grassland. Data shown mountain vegetation in Pampas grassland is adapted to fire, recovering cover and richness rapidly after fire and thus reducing soil erosion risks. Vegetation in mountain Pampas seems to be well adapted to fire, but in grasslands species composition has changed due to fire.

关键词： Amelichloa caudata Forbs Grass Natural grassland Nassella trichotoma Piedmont valleys shrubs sierra de la Ventana Vegetation functional groups

Human condition monitoring in hazardous locations using pervasive RFID sensor tags and energy-efficient wireless networks

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Journal of Zhejiang University-science C(Computers and Electronics) 2012年第9期13卷 674-688页

作者： Javier G.EsCRIBANO andrés GARCIA Autolog Group Industrial Engineering SchoolUniversity of Castilla-La ManchaAvda.Camilo José Cela s/n13071 Ciudad RealSpain

Tracking persons in dangerous situations as well as monitoring their physical condition, is often crucial for their safety. The systems commonly used for this purpose do not include individual monitoring or are too expensive and intrusive to be deployed in common situations. In this project, a mobile system based on energy-efficient wireless sensor networks (WsNs) and active radio frequency identification (RFID) has been developed to achieve ubiquitous positioning and monitoring of people in hazardous situations. The system designed can identify each individual, locate him/her, send data regarding their physical situation, and ascertain whether they are located in a confined space. A new algorithm called time division double beacon scheduling (TDDBs) has been implemented to increase operation time and data transmission rate of the nodes in the system. The results show that the use of this system allows us to find the location and state of a person, as well as to provide an analysis of the potential risks at each moment, in real time and in an energy-efficient way. In an emergency, the system also allows for quicker intervention, as it not only provides the location and causes of the event, but also informs about the physical condition of the individual at that moment.

关键词： Active RFID Wireless sensor networks (WsNs) ZigBee Human monitoring Time division double beacon sched-uling (TDDBs)

Engineering of immunoinstructive extracellular matrices for enhanced osteoinductivity

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Bioactive Materials 2023年第6期24卷 174-184页

作者： andrés García-García sébastien Pigeot Ivan Martin Department of Biomedicine University Hospital BaselUniversity of Basel4031BaselSwitzerland Department of Biomedical Engineering University of Basel4123AllschwillSwitzerland

The increasing recognition of the contribution of the immune system to activate and prime regeneration implies that tissue engineering strategies and biomaterials design should target regulation of early immunological *** previously proposed the cell-based engineering and devitalization of extracellular matrices(ECMs)as a strategy to generate implant materials delivering custom-defined ***,in the context of bone regeneration,we aimed at enhancing the osteoinductivity of such ECMs by enriching their immunomodulatory factors *** with IL1βa cell line overexpressing BMP-2 enabled engineering of ECMs preserving osteoinductive signals and containing larger amounts of angiogenic(VEGF)and pro-inflammatory molecules(IL6,IL8 and MCP1).Upon implantation,these IL1β-induced materials enhanced processes typical of the inflammatory phase(e.g.,vascular invasion,osteoclast recruitment and differentiation),leading to‘regenerative’events(e.g.,M2 macrophage polarization)and ultimately resulting in faster and more efficient bone *** results bear relevance towards the manufacturing of potent off-the-shelf osteoinductive materials and outline the broader paradigm of engineering immunoinstructive implants to enhance tissue regeneration.

关键词： Immunomodulation Bone tissue engineering Inflammation Hypertrophic cartilage matrices Osteoinduction

Object removal from complex videos using a few annotations

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Computational Visual Media 2019年第3期5卷 267-291页

作者： Thuc Trinh Le andrés Almansa Yann Gousseau simon Masnou LTCI T′el′ecom ParisTechUniversit′e Paris-Saclay75013 ParisFrance MAP5 CNRS&Universit′e Paris Descartes75006 ParisFrance Univ Lyon Universit′e Claude Bernard Lyon 1CNRS UMR 5208Institut Camille Jordan69622 VilleurbanneFrance

We present a system for the removal of objects from videos. As input, the system only needs a user to draw a few strokes on the first frame, roughly delimiting the objects to be removed. To the best of our knowledge, this is the first system allowing the semi-automatic removal of objects from videos with complex backgrounds. The key steps of our system are the following: after initialization, segmentation masks are first refined and then automatically propagated through the video. Missing regions are then synthesized using video inpainting techniques. Our system can deal with multiple, possibly crossing objects, with complex motions, and with dynamic textures. This results in a computational tool that can alleviate tedious manual operations for editing high-quality videos.

关键词： object removal object segmentation object tracking video inpainting video completion

In vitro effect of amoxicillin and clarithromycin on the 3' region of cagA gene in Helicobacter pylori isolates

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World Journal of Gastroenterology 2013年第36期19卷 6044-6054页

作者： Javier andrés Bustamante-Rengifo andrés Januer Matta Alvaro Pazos Luis Eduardo Bravo Registro Poblacional de Cáncer de Cali Department of Pathology School of Medicine Universidad del Valle Department of Biology Universidad de Nario

AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODs:One hundred and forty-nine clinical isolates of Helicobacter pylori(***)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study *** susceptibility was determined by the agar dilution *** isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer *** analyses was done using sPss 15.0statistical package,where each of the fingerprint bands were denoted as *** were designed by following Ward’s clustering method and the estimation of distances between each pair of *** isolates was calculated with the squared Euclidean ***:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double *** evidenced a high prevalence of the genotype cagA-positive/vacA *** 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic *** observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic *** gain and loss of EPIYA motifs resulted in a diversity of *** subclones after bacterial adjustment to changing conditions product of antibiotic *** PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic ***:Antibiotic pressure does not induce loss of the cag pathoge

关键词： Helicobacter pylori Antimicrobial susceptibility cag pathogenicity island cagA 3’region Random amplified polymorphic DNA-polymerase chain reaction

Assistive Robotics for Upper Limb Physical Rehabilitation:A systematic Review and Future Prospects

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 50-73页

作者： andrés Guatibonza Leonardo solaque Alexandra Velasco Lina Peñuela Department of Engineering Mechatronics EngineeringMilitar Nueva Granada UniversityBogotá1101111Colombia

Physical assistive robotics are oriented to support and improve functional capacities of *** physical rehabilitation,robots are indeed useful for functional recovery of affected ***,there are still open questions related to technological *** work presents a systematic review of upper limb rehabilitation robotics in order to analyze and establish technological challenges and future directions in this area.A bibliometric analysis was performed for the systematic literature *** from the last six years,conducted between August 2020 and May 2021,was *** methodology for the literature search and a bibliometric analysis of the metadata are *** a preliminary search resulted in 820 articles,a total of 66 articles were included.A concurrency network and bibliographic analysis were *** an analysis of occurrences,taxonomy,and rehabilitation robotics reported in the literature is *** review aims to provide to the scientific community an overview of the state of the art in assistive robotics for upper limb physical *** literature analysis allows access to a gap of unexplored options to define the technological prospects applied to upper limb physical rehabilitation robotics.

关键词： Upper limb Rehabilitation Assistive robotics Human-machine interaction Robotic systems Virtual reality Rehabilitation monitoring

Genomic variability of Helicobacter pylori isolates of gastric regions from two Colombian populations

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World Journal of Gastroenterology 2017年第5期23卷 800-809页

作者： andrés Jenuer Matta Alvaro Jairo Pazos Javier andrés Bustamante-Rengifo Luis Eduardo Bravo Registro Poblacional de Cáncer de Cali Department of PathologySchool of MedicineUniversidad del Valle Department of Biology Universidad de Narino

AIMTo compare the genomic variability and the multiple colonization of Helicobacter pylori (H. pylori) in patients with chronic gastritis from two Colombian populations with contrast in the risk of developing gastric cancer (GC): Túquerres-Nariño (High risk) and Tumaco-Nariño (Low risk).METHODsFour hundred and nine patients from both genders with dyspeptic symptoms were studied. seventy-two patients were included in whom H. pylori was isolated from three anatomic regions of the gastric mucosa, (31/206) of the high risk population of GC (Túquerres) and (41/203) of the low risk population of GC (Tumaco). The isolates were genotyped by PCR-RAPD. Genetic diversity between the isolates was evaluated by conglomerates analysis and multiple correspondence *** proportion of virulent genotypes of H. pylori was 99% in Túquerres and 94% in Tumaco. The coefficient of similarity of Nei-Li showed greater genetic diversity among isolates of Túquerres (0.13) than those of Tumaco (0.07). After adjusting by age, gender and type of gastritis, the multiple colonization was 1.7 times more frequent in Túquerres than in Tumaco (P = 0.05).CONCLUsIONIn Túquerres, high risk of GC there was a greater probability of multiple colonization by H. pylori. From the analysis of the results of the PCR-RAPD, it was found higher genetic variability in the isolates of H. pylori in the population of high risk for the development of GC.

关键词： Helicobacter pylori Pathogenicity islet cag cagA vacA Multiple colonization PCR-RAPD

Evaluation of a cost effective technique for treating aquaculture water discharge using Lolium perenne Lam as a biofilter

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Journal of Environmental sciences 2007年第9期19卷 1079-1085页

作者： NDUWIMANA andré College of Biosystems Engineering and Food sciences Zhejiang UniversityHangzhou 310029China.

Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN （total ammonia nitrogen）, 90% for NO2--N, 64.8% for NO3--N while for floating plant bed system 82.7% for TAN, 82% for NO2--N and 60.5% for NO3--N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN （total nitrogen） and TP （total phosphorus） load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.

关键词： recirculating system float system plant filter Lolium perenne Lam Amaranthus viridis Burundi

TWO COUNTERMEAsURE sTRATEGIEs TO MITIGATE RANDOM DIsRUPTIONs IN CAPACITATED sYsTEMs

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Journal of systems science and systems Engineering 2010年第2期19卷 210-226页

作者： Niyazi O.BAKIR Alex sAVACHKIN andrés Uribe-sANCHEZ Department of Industrial Engineering Bilkent University Department of Industrial and Management systems Engineering University of South Florida

We examine a capacitated system exposed to random stepwise capacity disruptions with exponentially distributed interarrival times and tmiformly distributed magnitudes. We explore two countermeasure policies for a risk-neutral decision maker who seeks to maximize the long-nm average reward. A one-phase policy considers implementation of countermeasures throughout the entirety of a disruption cycle. The results of this analysis form a basis for a two-phase model which implements countermeasures during only a fraction of a disruption cycle. We present an extensive numerical analysis as well as a sensitivity study on the fluctuations of some system parameter values.

关键词： Capacity analysis capacitated system lean random disruptions countermeasure policy