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Entropy model to assess sediment resuspension probability and trap efficiency of small dams

International journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco Jairo Soares Pereira Antonio Viana da Silva Filho josé Wellington Batista Lopes josé carlos de araújo department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model's tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

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Unpaved rural roads as source areas of sediment in a watershed of the Brazilian semi-arid region

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International journal of Sediment Research 2019年第5期34卷 475-485页

作者： Teresa Raquel Lima Farias Pedro Henrique Augusto Medeiros joaquín Navarro-Hevia josé carlos de araújo Federal Institute of Education Science and Technology of Ceará University of Valladolid Campus La Yutera Federal University of Ceará Department of Agricultural Engineering Campus do Pici

Approximately 80% of the road network in Brazil is unpaved and shows evidences of a high erosion potential. In the semi-arid Caatinga Biome in the northeast of the country, a monitoring programme has been done for two years in order to analyze runoff and sediment production from unpaved rural roadways and from embankments. Sediment production ranged from 0.30 to 0.92 Mg/ha yr, higher than in undisturbed areas, but generally lower than that reported for unpaved roads in other regions. However,this is a semi-arid area with low rainfall and runoff and, hence, with a limited hydrological connectivity and sediment production. Sediment production on an embankment with no vegetation was around ten times higher than on an embankment with vegetation. On the road surface, annual sediment production(normalized for gradient) in a section with traffic was three times higher than for a road surface without traffic. In addition, events that occurred after roadway maintenance activities generated peaks of sediment concentration of over 5000 mg/L. These results suggest that sediment production from roads and embankments with bare surfaces is at least one order of magnitude higher than in undisturbed catchment areas. Maintenance activity and vehicle traffic contribute to an increase in sediment availability and impact on the sediment concentration, but less intensely on sediment loads, which depend on the runoff magnitude of the events occurring after roadway maintenance. It was also found that the natural vegetation of the semi-arid region potentially captures sediment on roadway embankments; thereby playing an important role in breaking connectivity between the sediment flow from unpaved roads and the natural drainage system of the catchment.

关键词： Sediment production Caatinga vegetation Road maintenance Embankment

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Prehospital critical care drug-therapy and 30-day mortality in patients with acute respiratory disease

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World journal of Emergency Medicine 2025年第1期16卷 43-50页

作者： Jesús Jurado-Palomo joséLuis Martín-Conty Begoña Polonio-López Cristina Rivera Picón Raúl López-Izquierdo carlos del Pozo Vegas Pedro Ángel de Santos Castro Ancor Sanz-García Francisco Martín-Rodríguez Technological Innovation Applied to Health Research Group(ITAS) Faculty of Health SciencesCastilla-La Mancha UniversityTalavera de la Reina 45600Spain Nuestra Señora del Prado General Hospital Talavera de la Reina 45600Spain Emergency department Rio Hortega University HospitalValladolid 47012Spain CIBER of Respiratory Diseases(CIBERES) Institute of Health Carlos ⅢMadrid 28029Spain Faculty of Medicine University of ValladolidValladolid 470003Spain Emergency department University Clinical HospitalValladolid 47003Spain Prehospital Emergency Medical Services(SACYL) Valladolid 47007Spain

BACKGROUND: Prehospital medication is a reality, and the role of these therapies must be explored to assess their validity, especially for acute respiratory diseases, which are usually associated with increased morbidity. The aim of this study was to examine the association of prehospital medication use with mortality in patients with acute respiratory ***: A prospective, multicenter, emergency medical service(EMS) delivery cohort study was carried out in adults with unselected respiratory diseases managed by EMS who were transferred to the emergency department. From January 1, 2019, to October 31, 2023, six advanced life support units, thirty-eight basic life support units, and four hospitals in Spain participated in the study. demographic data, vital signs, use of mechanical ventilation, prehospital respiratory diagnosis, and prehospital medication were collected. The primary outcome was 30-day in-hospital ***: A total of 961 patients were included, with a mortality rate of 17.5%(168 patients). Age, an increasing number of comorbidities, the use of invasive mechanical ventilation(IMV), the use of major analgesics, hypnotics, and bicarbonate were risk factors. In contrast, elevated systolic blood pressure and Glasgow Coma Scale scores were found to be protective factors against mortality. The predictive capacity of the model reached an area under the curve(AUC) of 0.857(95% confidence interval [95% CI] 0.827–0.888).CONCLUSION: Our data revealed that IMV, major analgesics, hypnotics and bicarbonate administration were associated with elevated mortality. Adding prehospital drug therapy information to demographic variables and vital signs could improve EMS decision-making, allowing a better characterization of patients at risk of clinical worsening.

关键词： Drug-therapy Medication Prehospital Mortality Emergency medical services

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Effectiveness of different biochars in remediating a salt-affected Luvisol in Northeast Brazil

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Biochar 2021年第2期3卷 149-159页

作者： Wallace Melo dos Santos Maria Isidoria Silva Gonzaga joséAiron da Silva AndréQuintão de Almeida josécarlos de Jesus Santos Thomas Antonio Silva Gonzaga Idamar da Silva Lima EloáMoura araújo Water Resources Graduate Program Federal University of SergipeSão CristóvãoSE 49100‑000Brazil Agronomy department Federal University of SergipeSão CristóvãoSE 49100‑000Brazil Agriculture Engineering department Federal University of SergipeSão CristóvãoSE 49100‑000Brazil University of Notre Dame Notre DameIN 46556USA Soils and Agricultural Engineering department Federal University of ParanáCuritibaPR 80060‑000Brazil

Biochar has been proposed as a soil amendment to reclaim salt-affected ***,the evaluation of the different biochar types in these soils is essential due to the significant variation among biochar *** this study,biochars from sugarcane bagasse(SB),orange bagasse(OB),and corncob(CB)were applied alone and in the presence of gypsum(G)to test their potential to remediate a highly degraded saline-sodic soil in Brazil´s Northeast *** that,we conducted a laboratory column-leaching experiment and a greenhouse *** the column-leaching test,we analyzed the sodium adsorption ratio(SAR),the electrical conductivity of the saturation extract(ECe),the concentrations of major ions,and the exchangeable sodium percentage(ESP).Maize plants were grown in the leached soil in a ***-and corncob-derived biochars were more efficient than gypsum in reducing the soil salinity,bringing the indicators below threshold values,and optimizing soil reclamation *** ECe,SAR,and ESP were reduced to 3.42 dS m−1,1.64(mmolc dm−3)0.5 and 4.86%,respectively,in the SB treatment;and to 3.19 dS m−1,0.88(mmolc dm−3)0.5 and 2.53%,respectively,in the CB *** bagasse biochar did not effectively reduce the salinity *** biochar treatments improved seed germination and plant *** SB,CB,SBG,and CBG treatments increased plant height(478–558%),shoot mass(783–983%),and root mass(386–500%),***,the application of SB and CB is an effective alternative to remediate saline-sodic soils and to reduce the impact of soil salinity in the environment.

关键词： Biochar Soil remediation Soil salinity Corn growth

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Competition among rare earth elements on sorption onto six seaweeds

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journal of Rare Earths 2021年第6期39卷 734-741,I0005页

作者： joāo Pinto Marcelo Costa Bruno Henriques joséSoares Mariana Dias Thainara Viana Nicole Ferreira carlos Vale joséPinheiro-Torres Eduarda Pereira department of Chemistry University of Aveiro3810-193 AveiroPortugal CESAM Department of ChemistryUniversity of Aveiro3810-193 AveiroPortugal LAQV-REQUIMTE Department of Chemistry&Central Laboratory of AnalysisUniversity of Aveiro3810-193 AveiroPortugal CIIMAR一Interdisciplinary Centre of Marine and Environmental Research MatosinhosPortugal N9VE-Nature Ocean and ValueLdaPortoPortugal Central Laboratory of Analysis University of Aveiro3810-193 AveiroPortugal

Sorption has been proposed as a promising approach towards a sustainable water decontamination and recently to the recycling of rare earth elements(REE).Although living seaweed have been shown to be capable of removing REE from contaminated solutions,no studies have yet compared the effects of REE competition on sorption onto different groups of *** effects were analysed in the present study by exposing six living seaweeds(Ulva lactuca,Ulva intestinalis,Fucus spiralis,Fucus vesiculosus,Gracilaria *** Osmundea pinnatifida)(3 g/L,fresh weight) to mono-element and multi-element solutions of Y,La,Ce,Pr,Nd,Eu,Gd,Tb and Dy(1 μmol/L).Results show a preference towards light REE in mono-element solutions,which is reduced when in competition with other *** competitive effect is less pronounced in heavy REE indicating that these are still able to bind to the macroalgae despite the presence of competing *** to water content(%),seaweed specific surface area(cm^(2)/g) shows to be an important factor in the sorption of REE,since larger surface area is associated with higher removal and larger competitive effect.

关键词： Bioaccumulation Wastewater e-waste Recovery Removal Marine macroalgae

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A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： carlos Antonio Ribeiro Duarte Francisco joséde Souza Diego Nei Venturi Martin Sommerfeld department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed *** are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged *** option,although less commonly used,is the vortex-chamber *** both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating *** present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged *** are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion *** analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe *** general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of *** the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading ***,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics

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Effect of rare-earth oxides on properties of silicon nitride obtained by normal sintering and sinter-HIP

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journal of Rare Earths 2012年第11期30卷 1177-1183页

作者： Cecilia C.Guedes-Silva Flávio Machado de Souza Carvalho josé carlos Bressiani Nuclear and Energy Research Institute-IPEN/CNEN Geoscience Institute-IGC/USP

This paper presented the microstructure, mechanical properties and oxidation behavior of silicon nitride obtained by both conventional sintering and sintering followed by hot isostatic pressing （HIP）. Silicon nitride with additives such as 5 wt.% Al2O3 and 5 wt.% Ln203 （Ln= La, La concentrate, Gd or La＋Gd） were studied. The results revealed that Gd203 additions increased the formation of elongated grains of β-Si3N4, the fracture toughness and oxidation resistance. La2O3 additions led to higher densification and hardness values, while addition of La2O3 concentrate promoted the formation of materials with intermediate properties, compared to the other studied compositions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material, mainly because it allowed residual pores to close and also reduced the average aspect ratio of β-Si3N4 grains.

关键词： rare earths silicon nitride properties normal sintering sinter-HIP

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Behavior of wood basic density according to environmental variables

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journal of Forestry Research 2022年第2期33卷 497-505页

作者： Gabriel Marcos Vieira Oliveira joséMárcio de Mello carlos Rogério de Mello joséRoberto Soares Scolforo Eder Pereira Miguel Thiago Campos Monteiro Brazil Institute of Agricultural and Forestry defense of Espírito Santo(IDAF) Av.Lourival Lugon Moulinnº300CentroJerônimo MonteiroES CEP:29.550-000Brazil department of Forestry Sciences Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Engineering department Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Forestry Engineering department Faculdade de TecnologiaUniversity of Brasilia-UnBCampus Universitário Darcy RibeiroCaixa Postal 4357Asa Norte-BrasíliaDF CEP:70910-900Brazil department of Forestry Engineering and Technology Universidade Federal do Paraná-UFPRAv.Pref.Lothário Meissner632Jardim BotânicoCuritibaPR CEP:80.210-170Brazil

The relationships between climate conditions and wood density in tropical forests are still poorly *** quantify spatial dependence of wood density in the state of Minas Gerais(MG,Brazil),map spatial distribution of density,and correlate density with climate variables,we extracted data from the Forest Inventory of Minas Gerais for 1988 trees scaled throughout the territory and measured wood density of discs removed from the *** variables were extracted from the database of the Ecological-Economic Zoning of Minas *** spatial analysis,tree densities were measured at 44 georeferenced sampling *** data were subjected to exploratory analysis,variography,cross-validation,model selection,and ordinary *** relationships between wood density and environmental variables were calculated using dispersion matrices,linear correlation,and *** density proved to be highly spatially dependent,reaching a correlation of 96%,and was highly continuous over a distance of 228 *** distribution of wood density followed a continuous gradient of 514-659 kg m^(−3),enabling corre-lation with environment *** was correlated with mean annual precipitation(−0.57),temperature(0.63),and evapotranspiration(0.83).Geostatistical methods proved useful in predicting wood density in native tropical forests with different climate *** results confirmed the sensitivity of wood density to climate change,which could affect future carbon stock in forests.

关键词： Biomass Climate variables Geostatistics Hardwood Forest inventory Minas Gerais

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Leadership and organizational innovation in the third sector:A systematic literature review

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International journal of Innovation Studies 2020年第2期4卷 51-67页

作者： Francisco josé Nave do Adro joão carlos Correia Leitão department of Management and Economics University of Beira InteriorNECE-Research Center in Business SciencesEstrada do SineiroCovilhã6200-209Portugal

The impact of the global recession has served to increase pressure on non-profit organizations *** leadership is an essential component of the success of these *** two-fold purpose of this article is to provide a state-of-the-art overview about the existing literature on leadership and organizational innovation in the third sector,as well as to identify research gaps leading to a research model,which can be used in further empirical *** this,we used the collection of existing literature in the Web of *** 144 articles selected in the database were analysed using the VOS-viewer *** show a concern with the renewal of management bodies and a lack of qualified *** study contributes to the construction of an action agenda leading to the establishment of new leadership and organizational innovation model for the third sector.

关键词： Leadership Organizational innovation Third sector Non-profit organizations

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Diabetes mellitus and comorbidities in elderly people from the Lugu community:A critical-reflective analysis

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World journal of Diabetes 2024年第11期15卷 2162-2166页

作者： josécarlos Tatmatsu-Rocha josécarlos Gomes-Pinto College of Medicine Postgraduate Program in Physiotherapy and FunctionalityFederal University of Ceará-UFCFortaleza 60810-786Brazil College of Medicine Postgraduate Program in Physiotherapy and FunctionalityFederal University of CearáFortaleza 60000-000Brazil

Ageing has a close relationship with chronic non-communicable diseases,such as diabetes mellitus and high blood *** pathologies are often associated with changes in eating habits and promote crucial physiological changes which act silently in the long term in the elderly *** to the speed of urban development and technological advances,there has been an increase in the population's life ***,it is essential to know the socio-demographic profile and prevalent comorbidities of the elderly population,which can provide a reliable and broad database to enable the outline of strategies and the promotion of efficient health *** this sense,the purpose of this editorial is to contribute to the debate surrounding the article that analysed epidemiological data from the Lugu *** mellitus,hypertension and cardiovascular pathologies and their comorbidities were the most prevalent conditions in this *** data could contribute to develop public policies constructively and assertively,allowing investments in the prevention and treatment of these pathologies.

关键词： Diabetes mellitus Quality indicators Health care Hypertension Comorbidity Exercise

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