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Utilization of Pineapple Crown Fiber and Recycled Polypropylene for Production of Sustainable Composites

Journal of Renewable Materials 2020年第10期8卷 1327-1341页

作者： Alexandra Augusta Reichert Mariana Ribas de Sá Gabriela Escobar Hochmuller da Silva Cesar Augusto Gonçalves Beatrice andréricardo fajardo Amanda Dantas de Oliveira Postgraduate Program in Materials Science and Engineering(PPGCEM) Federal University of Pelotas(UFPel)Pelotas96075-630Brazil Technology Development Center(CDTec) Materials EngineeringFederal University of Pelotas(UFPel)Pelotas96075-630Brazil Postgraduate Program in Materials Science and Engineering(PPGCEM) Federal University of São Carlos(UFSCar)São Carlos13565-905Brazil Laboratory of Technology and Development of Composites and Polymeric Materials Federal University of Pelotas(UFPel)Pelotas96010-900Brazil

Nowadays,the production of consumer goods is based on the use of non-renewable raw materials,which in recent years has been performing as a problem for the *** the large number of available biofibers in nature,their use in the development of polymeric composites has inevitably emerged,it is also necessary to take into account the countless discarded plastics that still have the potential to be *** this work,fibers were extracted from pineapple crown residues and utilized to compose sustainable composites using recycled polypropylene from cups discarded in the trash as a ***,it is known that for good performance,it is necessary to achieve a good chemical interaction between the fiber and the *** order to improve this interaction,alkaline mercerization treatment was carried out on the surface of the fibers removing some components incompatible with the *** this work,the effect of the mercerization treatment on the properties of the fibers was studied,as well as their interaction with the *** effect of fiber concentration on the mechanical and thermal properties of composites was also *** of 5 and 7 wt%were used for both natural and mercerized fibers.A decrease in the number of degradation stages was observed through thermogravimetry analyses(from four in natural fiber to two in mercerized fibers),showing that the mercerization performed on the fibers was *** increase in the degree of crystallinity of mercerized fibers was also observed through the results of X-ray *** techniques indicate that amorphous compounds,such as hemicellulose and lignin,were partially *** the tensile test,it could be noted that all composites presented higher values of de elastic modulus than recycled polypropylene without added load;however,there were no differences in the elastic modulus between the different types of fibers and load ***,it is interesting to use fibers as r

关键词： Recycling composites polypropylene biofibers pineapple crown

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Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina

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Journal of Geographical Sciences 2025年第1期35卷 206-230页

作者： GARZO Pedro andrés DADON José Roberto ISLA Federico Ignacio Instituto de Investigaciones Marinas y Costeras (IIMyC-CONICET/UNMDP) Instituto de Geología de Costas y del Cuaternario Dr.Enrique J.Schnack (IGCC-CIC/UNMDP) Universidad de Buenos Aires Facultad de Arquitectura Dise?o y Urbanismo Centro de Investigaciones Gestión de Espacios Costeros (GEC-FADU/UBA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)

Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world. However, a century ago, they were considered hazardous environments due to their great dynamic nature. As a result, stabilization practices were considered necessary. The systematic introduction of fast-growing exotic trees helped stabilize the sand, making it easier for tourism urbanization to take place, but also leading to erosion processes. This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina. This complex region includes urban resorts, afforestation zones, and protected areas. A GIS-based geospatial analysis was conducted using a large satellite database(> 350 images), and the future evolution of the vegetation was modeled. The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover, accompanied by a concurrent reduction in sandy areas. In 1986, the dune area comprised 75% more surface than vegetation, whereas in 2021, it represented 60% less than vegetation. Furthermore, the 2050 scenario suggests a potential 40% reduction of dunes in certain areas. It is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance. Long-term management strategies must focus on restoring native plant communities and controlling invasive species, and avoiding new dune fixation initiatives based on the introduction of exotic species.

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Sailboat navigation control system based on spiking neural networks

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Control Theory and Technology 2023年第4期21卷 489-504页

作者： Nelson Santiago Giraldo Sebastián Isaza ricardo andrés Velásquez Department of Electronics and Telecommunications Engineering University of Antioquia67 stMedellin050010AntioquiaColombia

In this paper,we presented the development of a navigation control system for a sailboat based on spiking neural networks(SNN).Our inspiration for this choice of network lies in their potential to achieve fast and low-energy computing on specialized *** train our system,we use the modulated spike time-dependent plasticity reinforcement learning rule and a simulation environment based on the BindsNET library and USVSim *** objective was to develop a spiking neural network-based control systems that can learn policies allowing sailboats to navigate between two points by following a straight line or performing tacking and gybing strategies,depending on the sailing scenario *** presented the mathematical definition of the problem,the operation scheme of the simulation environment,the spiking neural network controllers,and the control strategy *** a result,we obtained 425 SNN-based controllers that completed the proposed navigation task,indicating that the simulation environment and the implemented control strategy work ***,we compare the behavior of our best controller with other algorithms and present some possible strategies to improve its performance.

关键词： Sailboat Control Spiking neuron Reinforcement learning BindsNet USVSim

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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

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CagA EPIYA polymorphisms in Colombian Helicobacter pylori strains and their influence on disease-associated cellular responses

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World Journal of Gastrointestinal Oncology 2013年第3期5卷 50-59页

作者： Carlos Alberto fajardo andrés Javier Quiroga andrea Coronado Karen Labrador Nicole Acosta Pilar Delgado Carlos Jaramillo María Mercedes Bravo Cancer and Infectious Agents Research Group National Cancer Institute Molecular Diagnostics and Bioinformatics Laboratory Biological Sciences Department Los Andes University

AIM: To investigate the influence of the CagA diversity in Helicobacter pylori (H. pylori ) strains from Colombia on the host cell biology. METHODS: Eighty-four H. pylori-cagA positive strains with different Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs patterns, isolated from patients with gastritis (n=17), atrophic gastritis (n=17), duodenal ulcer (n=16), intestinal metaplasia (n=16) and gastric cancer (n=18), were included. To determine the integrity of the cag pathogenicity island (cag PAI) we evaluated the presence of cagA, cagT, cagE, and cag10 genes by polymerase chain reaction. AGS gastric epithelial cellswere infected with each strain and assayed for translo-cation and tyrosine phosphorylation of CagA by western blot, secretion of interleukin-8 (IL-8) by enzyme-linked immuno sorbent assay after taking supernatants from cocultures and cell elongation induction. For cell elongation quantification, coculture photographs were taken and the proportion of "hummingbird" cells (>15 μm) was determined. RESULTS: Overall 72% (60/84) of the strains were found to harbor a functional cag PAI. Levels of phos-phorylated CagA were significantly higher for isolates from duodenal ulcer than the ones in strains from gas-tritis, atrophic gastritis, intestinal metaplasia and gastric cancer (49.1% ± 23.1% vs 21.1% ± 19.5%, P < 0.02; 49.1% ± 23.1% vs 26.2%±14.8%, P<0.045; 49.1% ± 23.1% vs 21.5% ± 19.5%, P<0.043 and 49.1% ± 23.1% vs 29.5% ± 27.1%, P < 0.047 respectively). We observed variable IL-8 expression levels ranging from 0 to 810 pg/mL and from 8.8 to 1442 pg/mL at 6 h and 30 h post-infection, respectively. cagPAI-defective strains did not induce detectable levels of IL-8 at 6 h post-infection. At 30 h post-infection all strains induced IL-8 expression in AGS cells, although cagPAI-defective strains induced significantly lower levels of IL-8 than strains with a functional cagPAI (57.1 ± 56.6 pg/mL vs 513.6 ± 338.6 pg/mL,P < 0.0001). We did not observe differences in the extent of cell

关键词： Helicobacter pylori cagA 3’region CagA protein Interleukin 8 Cell elongation Glu-Pro-Ile-Tyr-Ala

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Setpoint Feasibility and Stability of Wind Park Control Interactions at Weak Grids

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1790-1796页

作者： Argüello andrés IEEE the School of Electrical Engi‐neering and Computation University of CampinasCampinasBrazil

The controllers of wind parks that are connected to weak grids can induce unstable oscillations near the fundamental *** phenomenon can be studied with equivalent impedances of the wind generators,which depend on their operational setpoints at the fundamental *** feasibility of such setpoint,i.e.,solution to the power flow,does not depend on the control ***,oscillations from unfeasible setpoints and control instabilities both occur at weak grids and near the fundamental *** letter presents an exploratory study to map the conditions where both phenomena occur,using sensitivity studies comprising multiple setpoints and control parameter *** results are visually presented as the regions which inform the configurations leading to unfeasible setpoints,and unstable control interaction *** the results,it can be observed that the trajectory of the eigenvalues in the Nyquist plots towards an unfeasible setpoint approaches a fundamental frequency instability.

关键词： Control interaction impedance power quality resonance stability wind generator

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Aquaculture Solids Management Using A Combination of Sand/Gravel or Unwoven Fabric Bed With Lolium perenne Lam as A Plant Biofilter

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Biomedical and Environmental Sciences 2007年第6期20卷 439-444页

作者： andr NDUWIMANA Institute of Agricultural and Bio-Environmental Engineering College of Biosystems Engineering and Food Sciences Zhejiang University

Objective This work is an evaluation of the efficiency of a sand-gravel or unwoven fabric bed system and Lolium perenne Lam as plant biofilter in the reduction of solids and nutrients removal from aquaculture discharge water. Methods The fzrst step consisted of the collection of wastewater in the tank and the distribution at three different hydraulic loading regimes （0.5, 1, 1.5 L/hour） to the different experimental systems. The second step was to evaluate the performance of the different systems. The fzrst system consisted of a bucket filled with a substrate of sand/gravel （20 cm in depth）, on the bottom of which was a 80 mesh/inch2 of nylon （S1）; the second was similar, but was planted with Lolium perenne lam （S2）; the third was planted with a grass plate consisting of 7 layers of unwoven fabric planted with L. perenne （S3）. Results The second system showed the best performance in reducing solids as well as in nutrients （TN, TP, and COD） reduction. The removal rates for TS, TN, and TP were negatively correlated with the loading regimes, with 0.5 L/hour being the most efficient and thus taken as the reference. Conclusions Solids management using a sand/gravel substrate as bed culture and Lolium perenne L. as plant biofilter has proved to be an efficient technique for solids reduction with low operating cost. This grass plays an important role in wastewater eco-treatment by absorbing dissolved pollutants （TAN） as nutrients for its growth.

关键词： Lolium perenne lam Hydraulic loading regimes Microcosm

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Acute cholestatic hepatitis caused by amoxicillin/ clavulanate

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World Journal of Gastroenterology 2013年第46期19卷 8789-8792页

作者： Daniel Oliveira Beraldo Joanderson Fernandes Melo Alexandre Vidal Bonfim andrei Alkmim Teixeira ricardo Alkmim Teixeira andré Loyola Duarte Department of Internal Medicine Hospital Renascentista Escola Paulista de Medicina-UNIFESP Nephrology Department Escola Paulista de Medicina-UNIFESP Cardiology Department Cardiology Department Instituto do Cora o-FMUSP Pathology Department Hospital A.C.CamargoSo Paulo

Amoxicillin/clavulanate is a synthetic penicillin that is currently commonly used,especially for the treatment of respiratory and cutaneous *** general,it is a well-tolerated oral ***,amoxicillin/clavulanate can cause adverse effects,mainly cutaneous,gastrointestinal,hepatic and hematologic,in some *** here is a case report of a 63-yearold male patient who developed cholestatic hepatitis after recent use of amoxicillin/*** 6 wk of prolonged use of the drug,he began to show signs of cholestatic icterus and developed severe hyperbilirubinemia(total bilirubin>300 mg/L).Diagnostic investigation was conducted by ultrasonography of the upper abdomen,serum tests for infection history,laboratory screening of autoimmune diseases,nuclear magnetic resonance(NMR)of the abdomen with bile duct-NMR and transcutaneous liver biopsy guided by *** duration of disease was approximately 4 mo,with complete resolution of symptoms and laboratory changes at the end of that time *** treatment was not instituted,only a combination of anti-emetic(metoclopramide)and cholestyramine for pruritus.

关键词： Hepatology Hepatitis Amoxicillin/Clavula-nate Drug reactions Hyperbilirubinemia

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Litterfall production modeling based on climatic variables and nutrient return from stands of Eucalyptus grandis Hill ex Maiden and Pinus taeda L.

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Journal of Forestry Research 2024年第5期35卷 26-36页

作者： andrés Baietto andrés Hirigoyen Jorge Hernández Amabelia del Pino Forest Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay National Research Program of Forest Production National Agriculture Research InstituteINIA97000 TacuarembóUruguay Soil and Water Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay

Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus *** short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient *** model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic *** temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by ***;seasonal accumulated precipitation and mean maximum temperature affected litterfall by *** regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for ***(N=33;MAE(mean absolute error)=0.65;RMSE(root mean square error)=0.91;R^(2)=0.71)and ***(N=108;MAE=1.50;RMSE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(***:Ca>N>K>Mg>P;***:N>Ca>K>Mg>P)and micronutrients(*** and ***:Mn>Fe>Zn>Cu)in both *** study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

关键词： Afforestation Litterfall Nutrient recycling Climate modeling Myrtaceae Pinaceae

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Surface movement above old coal longwalls after mine closure

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International Journal of Mining Science and Technology 2017年第3期27卷 481-490页

作者： andré Vervoort Pierre-Yves Declercq Department of Civil Engineering KU Leuven Leuven 3001 Belgium Geological Survey of Belgium Royal Belgian Institute of Natural Sciences Brussels 1000 Belgium

Although most subsidence occurs in the months and years after mining by the longwall method, surface movement is still occurring many decades after the mining. The aim of the study is to quantify the long term behavior. Satellite data(radar-interferometry) were analyzed to study an area of about 2 km^2 during the 18 years following the closure of the underground infrastructure and the flooding of the underground workings and rock mass. It was observed that, on average, a residual downward movement took place till 7–12 years after the closure, followed by a clear uplift. However, the first signs of an uplift occurred in certain sub-areas 3–4 years after the closure. Zones within the area studied were identified with either larger or smaller movements. However, the spatial variation of the surface subsidence or uplift could not be directly explained by the characteristics of mining.

关键词： Coal mining Surface movement Subsidence Uplift Radar-interferometry

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