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A Study of Fluid Flow in Sediments and the effect of Tidal Pumping

Journal of earth Science 2017年第5期28卷 842-847页

作者： paulo Waltrich John Whitehead Richard Hughes Karsten Thompson Department of Petroleum engineering Louisiana State University

Offshore drilling and production operations can result in spills or leaks of hydrocarbons into seabed sediments, which can potentially contaminate these sediments with oil. If this oil later mi- grates to the water surface it has the potential for negative environmental impacts. For proper contin- gency planning and to avoid larger consequences in the environment, it is essential to understand me- chanisms and rates for hydrocarbon migration from oil containing sediments to the water surface as well as how much will remain trapped in the sediments. It is believed that the amount of oil transported out of the sediment can be affected by tidal pumping, a common form of subterranean groundwater dis- charge （SGD）. However, we could find no study experimentally investigating the phenomenon of fluid flow in subsea sediments containing oil and the effects of tidal pumping. This study presents an experi- mental investigation of tidal pumping to determine if it is a possible mechanism that may contribute to the appearance of an oil sheen on the ocean surface above a sediment bed containing oil. An experimen- tal apparatus was constructed of clear PVC pipe allowing for oil migration to be monitored as it flowed out of a sand pack containing oil, while tidal pressure oscillations were applied in three different man- ners. The effect of tidal pumping was simulated via compression of air above the water （which simulated the increasing static head from tidal exchange）. experimental results show that sustained oil release oc- curred from all tests, and tests with oscillating pressure produced for longer periods of time. Further- more, the experimental results showed that the oil migration rate was affected by grain size, oil satura- tion, and oscillation wave type. In all oscillating experiments the rate and ultimate recovery was less than the comparable static experiments. For the conditions studied, the experimental results indicate that with an oscillating pressure on top of a

关键词： tidal pumping oil migration sediments oil release rate.

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Rainfall erosivity and erosivity density through rainfall synthetic series for Sao paulo State,Brazil:Assessment,regionalization and modeling

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International Soil and Water Conservation Research 2022年第3期10卷 355-370页

作者： David Bruno de Sousa Teixeira Roberto Avelino Cecílio Joao paulo Bestete de Oliveira Laura Thebit de Almeida Gabrielle Ferreira Pires Department of Agricultural engineering Federal University of ViçosaViçosaMG36570-900Brazil Department of Forest and Wood Sciences Federal University of Espírito SantoJer^onimo MonteiroES29550-000Brazil Federal Institute of espírito Santo Campus AlegreAlegreES29520-000Brazil

Rainfall is the main cause of erosion of Brazilian soils,which makes assessing the rainfall erosivity factor(Re)and the erosivity density(eD)fundamental for soil and water ***,the objectives of this study were:i)to estimate the Re and eD for Sao paulo State,Brazil,using synthetic series of pluviographic data;ii)to define homogeneous regions regarding rainfall erosivity;and iii)to generate regression models for rainfall erosivity estimates in each of the homogeneous *** series of pluviographic data were initially obtained on a sub-daily scale from the daily rainfall records of 696 rainfall *** Re values were then estimated from the synthetic rainfall data,and eD was calculated from the relationship between erosivity and rainfall *** and annual maps for Re and eD were *** clustering analysis was used to define homogeneous regions in terms of rainfall erosivity,and regionalized regression models for estimating Re were *** results demonstrate high spatial variability of Re in Sao paulo,where the highest annual values were observed in the coastal *** to March concentrate approximately 60%of the intra-annual *** highest values of annual eD were observed in regions with intense agricultural *** definition of five homogeneous regions concerning the rainfall erosive potential evidenced distinct seasonal patterns of the spatial distribution of ***,the high predictive accuracy of the regionalized models obtained characterizes them as essential tools for reliable estimates of rainfall erosivity,and contribute to better soil conservation planning.

关键词： Soil erosion Stochastic weather generator Homogeneous regions Modified Fournier index Regression models

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Proportionally Modular Diophantine Inequalities and Their Multiplicity

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Acta Mathematica Sinica,english Series 2010年第11期26卷 2059-2070页

作者： José Carlos ROSALeS Manuel Batista BRANCO paulo VASCO Departamento de lgebra Universidad de Granada Departamento de Matemática Departamento de Matemática Universidade de Trás-os-Montes e Alto Douro

Let I be an interval of positive rational numbers. Then the set S （I） = T ∩ N, where T is the submonoid of （Q0＋, ＋） generated by T, is a numerical semigroup. These numerical semigroups are called proportionally modular and can be characterized as the set of integer solutions of a Diophantine inequality of the form ax rood b 〈 cx. In this paper we are interested in the study of the maximal intervals I subject to the condition that S （I） has a given multiplicity. We also characterize the numerical semigroups associated with these maximal intervals.

关键词： Numerical semigroup Diophantine inequality multiplicity Frobenius number

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Analysis of Surface Integrity in Drilling Metal Matrix and Hybrid Metal Matrix Composites

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Journal of Materials Science & Technology 2012年第8期28卷 761-768页

作者： T.Rajmohan K.Palanikumar J.paulo Davim Department of Mechanical engineering Sri Chandrasekharendra Saraswathi Viswa Maha Vidyalaya University Department of Mechanical engineering Sri Sai Ram Institute of Technology Department of Mechanical engineering University of AveiroCampus Santiago3810-193 AveiroPortugal

Hybrid metal matrix composites consist of at least three constituents-a metal or an alloy matrix and two reinforcements in various forms, bonded together at the atomic level in the composite. Despite their higher specific properties of strength and stiffness, the non homogeneous and anisotropic nature combined with the abrasive reinforcements render their machining difficult. In this paper, the surface integrity of machining in drilling hybrid composites has been discussed. Drilling tests are carried out at different spindle speed, feed rates, and different drill tool materials to investigate the effect of the various cutting parameters on the surface quality and the extent of the deformation of drilled surface due to drilling. Materials used for the present investigation are A1356/IOSIC （wt%） metal matrix and A1356/10SiC-3mica （wt%） hybrid composites. The composites are fabricated using stir casting route. The drilling tests are conducted on vertical computer numeric control （CNC） machining center using carbide, coated carbide and polycrystalline diamond （PCD） drills. The surface roughness decreases with increasing spindle speed and increases with increasing feed rate. The machined surface is analyzed by scanning electron microscopy （SeM）. SeM images of the machined surfaces indicate the presence of grooves and pits. Microhardness depth profiles indicate that the subsurface damage is limited to the top of 100-250 μm.

关键词： Hybrid composites Scanning electron microscopy (SeM) Subsurface Drilling

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effects of bioactive compounds from Pleurotus mushrooms on COVID-19 risk factors associated with the cardiovascular system

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Journal of Integrative Medicine 2022年第5期20卷 385-395页

作者： eduardo echer dos Reis paulo Cavalheiro Schenkel Marli Camassola Department of Physiology Federal University of Rio Grande do SulCampus Centro 90050-170 Porto AlegreBrazil enzymes and Biomass Laboratory Institute of BiotechnologyUniversity of Caxias do Sul95070-560 Caxias do SulBrazil Department of Physiology and Pharmacology Federal University of PelotasCampus Capão do Leão96900-010 PelotasBrazil

Mushrooms are a group of fungi with great diversity and ultra-accelerated *** a consequence,mushrooms have developed a protective mechanism consisting of high concentrations of antioxidants such as selenium,polyphenols,β-glucans,ergothioneine,various vitamins and other bioactive *** mushrooms of the Pleurotus genus have generated scientific interest due to their therapeutic properties,especially related to risk factors connected to the severity of coronavirus disease 2019(COVID-19).In this report,we highlight the therapeutic properties of Pleurotus mushrooms that may be associated with a reduction in the severity of COVID-19:antihypertensive,antihyperlipidemic,antiatherogenic,anticholesterolemic,antioxidant,anti-inflammatory and antihyperglycemic *** properties may interact significantly with risk factors for COVID-19 severity,and the therapeutic potential of these mushrooms for the treatment or prevention of this disease is *** this,studies show that regular consumption of Pleurotus species mushrooms or components isolated from their tissues is beneficial for immune *** species mushrooms may have a role in the prevention or treatment of infectious diseases either as food supplements or as sources for pharmacological agents.

关键词： Pleurotus Food supplements COVID-19 SARS-Cov-2 Coronavirus Antiviral agents

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Recent advances in magnetic electrospun nanofibers for cancer theranostics application

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Progress in Natural Science:Materials International 2021年第6期31卷 835-844页

作者： Paula I.P.Soares Jo?o paulo Borges CeNIMAT/i3N Departamento de Ciência dos Materiais Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa

Cancer theranostics is a recent concept that aims to combine in the same device diagnostic and therapeutic features. Magnetic nanoparticles(m NPs) are commonly used as a critical part of these systems due to their ability to respond to an external magnetic field. Consequently, m NPs can generate heat when an alternating magnetic field is applied and enhance image contrast in magnetic resonance. However, direct administration of m NPs intravenously or directly in the tumor can lead to undesired side effects because of m NP elimination by macrophages or leakage to healthy tissues. Therefore, m NPs can be retained in a polymeric nanofibrous mesh, thus preventing misplacing or loss of m NPs. Furthermore, these magnetic nanofibers can be directly implanted in the tumor site, thus ensuring high m NPs loading and higher magnetic response. In addition, polymeric nanofibers produced by electrospinning are frequently used to maintain a sustained drug release in the tumor site. Therefore,a magnetic polymeric nanofiber produced by electrospinning is an ideal nanosystem for cancer theranostics application. This review summarizes the most recent developments of magnetic nanofibers produced by electrospinning for cancer theranostics applications.

关键词： electrospinning Nanofibers Iron oxide nanoparticles Magnetic fluid hyperthermia Cancer theranostics

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Phenolic compounds of green tea: Health benefits and technological application in food

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 709-719页

作者： Jose Manuel Lorenzo paulo eduardo Sichetti Munekata Meat Technological Center of Galicia Galicia Street No.4 Parque Tecnolgico de Galicia San Cibrao das Vinas Department of Food engineering Faculty of Animal Science and Food Engineering University of Sao Paulo

Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodegenerative diseases. Particularly, epigallocatechin gallate has been implicated in alteration mechanisms with protective effect in these diseases as indicated by several studies about the effect of green tea consumption and mechanistic explanation through in vitro and in vivo experiments. The biological activity of green tea phenolic compounds also promotes a protective effect by antioxidant mechanisms in biological and food systems, preventing the oxidative damage by acting over either precursors or reactive species. extraction of phenolic compounds influences the antioxidant activity and promotes adequate separation from green tea leaves to enhance the yield and/or antioxidant activity. Application of green tea phenolic compounds is of great interest because the antioxidant status of the products is enhanced and provides the product with additional antioxidant activity or reduces the undesirable changes of oxidative reactions while processing or storing *** this scenario, meat and meat products are greatly influenced by oxidative deterioration and microbial spoilage, leading to reduced shelf life. Green tea extracts rich in phenolic compounds have been applied to increase shelf life with comparable effect to synthetic compounds, commonly used by food industry. Green tea has great importance in general health in technological application, however more studies are necessary to elucidate the impact in pathways related to other diseases and food applications.

关键词： Phenolic profile Healthy Neurodegenerative diseases extraction of polyphenols Antioxidant mechanism Food stability

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Continuous positive airway pressure acutely increases exercise duration in children with severe therapy-resistant asthma:a randomized crossover trial

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World Journal of Pediatrics 2021年第2期17卷 189-196页

作者： Claudia Silva Schindel Daniele Schiwe Joao paulo Heinzmann-Filho Natalia evangelista Campos paulo Marcio Pitrez Marcio Vinicius Fagundes Donadio Laboratory of Pediatric Physical Activity Centro Infant.Pontiffcia Universidade Catolica do Rio Grande do Sul(PUCRS)Av.Ipiranga6690.2°andarPorto AlegreRS CEP 90610-000.Brazil Hospital Moinhos de Vento Porto AlegreBrazil and Centro InfantPontiffcia Universidade Catolica do Rio Grande do Sul(PUCRS)Porto Alegre.Brazil

Background Lower exercise tolerance is an important component of asthma and the possible effects of non-invasive ven-tilation on exercise capacity in individuals with severe therapy-resistant asthma(STRA)are *** study aimed to evaluate the immediate effect of continuous positive airway pressure(CPAP)on exercise tolerance in children with *** We performed a controlled,randomized,crossover clinical trial including subjects aged 6 to 18 years old diagnosed with ***,anthropometric and lung function data were *** participants in the intervention group(IG)used CPAP(PeeP 10cmH2O and FiO20.21)for a period of 40 *** in the control group(CG)used CPAP with mini-mum PeeP at 1 cmH20 also for 40 ***,subjects from both groups underwent cardiopulmonary exercise testing(CPeT).After a 15-day washout period,on a subsequent visit,subjects participated in the opposite group to the initial *** Thirteen subjects with a mean age of 12.30±1.7 years were *** variables of peak expiratory flow(PeF)and forced expiratory volume in the first second(FeV1)before using CPAP and after performing CPeT did not show sig-nificant *** CPeT results,there was no significant difference(P=0.59)between groups at peak exercise for oxygen consumption—VO2(CG:33.4±6.3 and IG:34.5±5.9,mL kg^(-1)min^(-1)).However,the IG(12.4±2.1)presented a total test time(min)significantly(P=0.01)longer than the CG(11.5±1.3).Conclusion The results suggest that the use of CPAP before physical exercise increases exercise duration in children and adolescents with STRA.

关键词： Asthma Non-invasive ventilation Oxygen consumption exercise test exercise tolerance exercise-induced bronchospasm

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Repeat hepatectomy for recurrent colorectal liver metastases:A comparative analysis of short-and long-term results

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Hepatobiliary & Pancreatic Diseases International 2022年第2期21卷 162-167页

作者： paulo Figueiredo Costa Fabricio Ferreira Coelho Vagner Birk Jeismann Jaime Arthur Pirola Kruger Gilton Marques Fonseca Ivan Cecconello paulo Herman Digestive Surgery Brazilian College of Digestive Surgery(Colégio Brasileiro de Cirurgia Digestiva-CBCD) São PauloBrazil Digestive Surgery Division Department of GastroenterologyUniversity of São Paulo School of MedicineSão PauloBrazil Instituto do Câncer do estado de São paulo(ICeSP) São PauloBrazil

Background: Liver recurrence after resection of colorectal liver metastases(CRLM) is frequent. Repeat hepatectomy has been shown to have satisfactory perioperative results. However, the long-term outcomes and the benefts for patients with early recurrence have not been clarifed. The aim of this study was to compare the short-and long-term outcomes of patients undergoing single hepatectomy and repeat hepatectomy for CRLM. Additionally, the oncological outcomes of patients with early( ≤ 6 months) and late recurrence who underwent repeat hepatectomy were compared. Methods: Consecutive adult patients undergoing hepatectomy for CRLM between June 20 0 0 and February 2020 were included and divided into two groups: single hepatectomy and repeat hepatectomy. Results: A total of 709 patients were included: 649 in the single hepatectomy group and 60 in the repeat hepatectomy group. Patients in the repeat hepatectomy group underwent more cycles of preoperative chemotherapy [4(3-6) vs. 3(2-4), P = 0.003]. Patients in the single hepatectomy group more frequently underwent major hepatectomies(34.5% vs. 16.7%, P = 0.004) and had a greater number of lesions resected(2.9 ± 3.6 vs. 1.9 ± 1.8, P = 0.011). There was no increase in operative time, estimated blood loss, length of hospital stay, complications, or mortality in the repeat hepatectomy group. There were no differences in overall survival( P = 0.626) and disease-free survival( P = 0.579) between the two groups. Similarly, for patients underwent repeat hepatectomy, no difference was observed between the early and late recurrence groups in terms of overall survival( P = 0.771) or disease-free survival( P = 0.350). Conclusions: Repeat hepatectomy is feasible and safe, with similar short-and long-term outcomes when compared to single hepatectomy. Surgical treatment of early liver recurrence offers similar oncological outcomes to those obtained for late recurrence.

关键词： Colorectal cancer Metastasis Hepatectomy Postoperative complications Survival analysis

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exploring the drivers of urban expansion in a medium-class urban agglomeration in India using the remote sensing techniques and geographically weighted models

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Geography and Sustainability 2023年第2期4卷 150-160页

作者： Tirthankar Basu Arijit Das paulo Pereira Department of Geography University of Gour BangaMalda 732103West BengalIndia environmental Management Laboratory Mykolas Romeris University VilniusLithuania

Rapid urbanization urges the immediate attention of policymakers to ensure sustainable city ***-standing the urban growth drivers is essential to address effective strategies for urbanization-related *** work aims to study Raiganj’s urban development and the factors associated with this *** study employed global logistic regression(LR)and geographical weighted logistic regression(GWLR)to explore the role of different *** results showed that the role of the central business district(covariate>-1),commercial market(covariate>-3),and police station(covariate>-4)were significant to the development of new built-up *** the second period,major roads(covariate>-2)and new infrastructures(covariate>-4)became more relevant,particularly in the eastern and southern *** was more accurate in assessing the different fac-tors’impact than *** results obtained are essential to understanding urban expansion in India’s medium-class cities,which is critical to effective policies for sustainable urbanization.

关键词： Drivers Geographically weighted logistic regression (GWLR) Logistic regression LULC Urban growth

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