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Influence of PVD-duplex-treated, Bionic Surface Structures on the Wetting Behavior for Sheet-Bulk Metal Forming Tools

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journal of Bionic Engineering 2017年第3期14卷 520-531页

作者： Wolfgang Tiilmann Dominic Stangier Nelson Filipe lopes Dias Institute of Materials Engineering TU Dortmund 44227 Dortmund Germany Leonhard-Euler-Strafle 2

Bionic surface structures, inspired by the flora, were developed for Sheet-Bulk Metal Forming （SBMF） in order to locally control the friction condition by adjusting the wetting behavior. Five bionic structures were micromilled on ASP 2023 in annealed as well as hardened and tempered conditions. Subsequently, the structured surfaces were plasma-nitrided and coated with a CrA1N thin film. The influence of the treatment method on the structural geometry was investigated with the aid of a scanning electron microscope and 3D-profilometer. The wetting behaviors of water and deep drawing oil （Berufluid ST6007） on bionic surfaces were evaluated using contact angle measurements. The resulting micro-milled structures exhibit an almost identical shape as their bionic models. However, the roughness of the structured surfaces is influenced by the microstructure. The combination of plasma-nitriding and Physical Vapor Deposition （PVD） leads to an increase in roughness. All bionic struc- tures possess higher contact angles than that of the unstructured surfaces when wetted by water. This can be explained by the fact that the structural elevations block the spreading. When the bionic surfaces are wetted by deep drawing oil, the lubricant spreads in the structural cavities, leading to smaller contact angles. Furthermore, the anisotropy of the structure has an influence on the wetting behavior.

关键词： bionic structures sheet-bulk metal forming CrA1N PVD-duplex treatment wetting behavior

Solar-stellar astrophysics and dark matter

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Research in Astronomy and Astrophysics 2012年第8期12卷 1107-1138页

作者： Sylvaine Turck-Chize Ilídio lopes CEA/IRFU/Service d'Astrophysique AIMCE Saclay91191 Gif sur YvetteFrance Centro Multidisciplinar de Astrofísica Instituto Superior TcnicoUniversidade Tcnica de LisboaAv.Rovisco Pais1049-001 LisboaPortugal Departamento de Física Escola de Ciência e TecnologiaUniversidade de vora Colgio Luis António Verney7002-554 voraPortugal

In this review, we recall how stars contribute to the search for dark matter and the specific role of the Sun. We describe a more complete picture of the solar interior that emerges from neutrino detections, gravity and acoustic mode measurements of the Solar and Heliospheric Observatory （SOHO） satellite, becoming a reference for the most common stars in the Universe. The Sun is a unique star in that we can observe directly the effect of dark matter. The absence of a signature related to Weakly Interacting Massive Particles （WIMPs） in its core disfavors a WIMP mass range below 12 GeV. We give arguments to continue this search on the Sun and other promising cases. We also examine another dark matter candidate, the sterile neutrino, and infer the limitations of the classical structural equations. Open questions on the young Sun, when planets formed, and on its present internal dynamics are finally dis- cussed. Future directions are proposed for the next decade： a better description of the solar core, a generalization to stars coming from seismic missions and a better under- standing of the dynamics of our galaxy which are all crucial keys for understanding dark matter.

关键词： stellar evolution: theory -- elementary particles -- helioseismology --dark matter -- early solar-planet relationship

A novel color image encryption algorithm based on a fractional-order discrete chaotic neural network and DNA sequence operations

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Frontiers of Information Technology & Electronic Engineering 2020年第6期21卷 866-879页

作者： Li-ping CHEN Hao YIN Li-guo YUAN António M.lopes j.A.Tenreiro MACHADO Ran-chao WU School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou 510642China UISPA–LAETA/INEGI Faculty of EngineeringUniversity of PortoRua Dr.Roberto FriasPorto 4200-465Portugal Department of Electrical Engineering Polytechnic Institute of PortoR.Dr.António Bernardino de Almeida431Porto 4249-015Portugal School of Mathematical Sciences Anhui UniversityHefei 230601China

A novel color image encryption algorithm based on dynamic deoxyribonucleic acid(DNA)encoding and chaos is presented.A three-neuron fractional-order discrete Hopfield neural network(FODHNN)is employed as a pseudo-random chaotic sequence *** initial value is obtained with the secret key generated by a fiveparameter external key and a hash code of the plain *** external key includes both the FODHNN discrete step size and *** hash is computed with the SHA-2 *** ensures a large secret key space and improves the algorithm sensitivity to the plain ***,a new three-dimensional projection confusion method is proposed to scramble the pixels among red,green,and blue color *** encoding and diffusion are used to diffuse the image ***-random sequences generated by FODHNN are employed to determine the encoding rules for each pixel and to ensure the diversity of the encoding ***,confusion II and XOR are used to ensure the security of the *** results and the security analysis show that the proposed algorithm has better performance than those reported in the literature and can resist typical attacks.

关键词： Fractional-order discrete systems Neural networks Deoxyribonucleic acid(DNA)encryption Color image encryption

Avocado and Cardiovascular Health

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Open journal of Endocrine and Metabolic Diseases 2015年第7期5卷 77-83页

作者： Camila Weschenfelder júlia Lorenzon dos Santos Priscilla Azambuja lopes de Souza Viviane Paiva de Campos Aline Marcadenti Postgraduate Studies Program in Cardiology Instituto de Cardiologia/Fundacao Universitária de Cardiologia do Rio Grande do Sul (IC/FUC) Porto Alegre Brazil Department of Nutrition Federal University of Health Sciences of Porto Alegre (UFCSPA) Porto Alegre Brazil

Avocado is a fruit which had a caloric density of 1.7 kcal per gram and a half unit (~70 g) is composed by 114 kcal, 4.6 g of fibers, 345 mg of potassium, 19.5 mg of magnesium, 1.3 mg of vitamin E and 57 mg of phytosterols. Approximately 75% of fiber’s avocado contents are considered insoluble and 25% are soluble. The avocado contains lipids that consist of 71% from monounsaturated fatty acids (MUFA), 13% from polyunsaturated (PUFA) and 16% from saturated fatty acids (SFA). Recent researches have shown that avocado may improve hypercholesterolemia and may be useful in the treatment of hypertension and type 2 diabetes mellitus (T2DM). This way, avocado plays an important role in the cardiovascular health. This review summarizes the potential benefits of avocado consumption in the prevention of cardiovascular risk factors and metabolic diseases.

关键词： Persea Diabetes Mellitus Type 2 Dyslipidemias Nutritional Status Blood Pressure

Multidrug-resistant bacterial infections after liver transplantation: An ever-growing challenge

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World journal of Gastroenterology 2014年第20期20卷 6201-6210页

作者： Guilherme Santoro-lopes Erika Ferraz de Gouvêa Infectious Diseases Clinic Hospital Universitário Clementino Fraga Filho Universidade Federal do Rio de Janeiro Rio de Janeiro RJ-CEP 21941-913 Brazil Department of Preventive Medicine School of Medicine Universidade Federal do Rio de Janeiro Rio de Janeiro RJ-CEP 21941-590 Brazil

Bacterial infections are a leading cause of morbidity and mortality among solid organ transplant *** the last two decades,various multidrug-resistant(MDR)pathogens have emerged as relevant causes of infection in this *** this fact reflects the spread of MDR pathogens in health care facilities worldwide,several factors relating to the care of transplant donor candidates and recipients render these patients particularly prone to the acquisition of MDR bacteria and increase the likelihood of MDR infectious outbreaks in transplant *** awareness of this high vulnerability of transplant recipients to infection leads to the more frequent use of broad-spectrum empiric antibiotic therapy,which further contributes to the selection of drug *** vicious cycle is difficult to avoid and leads to a scenario of increased complexity and narrowed therapeutic *** by MDR pathogens is more frequently associated with a failure to start appropriate empiric antimicrobial *** lack of appropriate treatment may contribute to the high mortality occurring in transplant recipients with MDR ***,high therapeutic failure rates have been observed in patients infected with extensively-resistant pathogens,such as carbapenemresistant Enterobacteriaceae,for which optimal treatment remains *** such a context,the careful implementation of preventive strategies is of utmost importance to minimize the negative impact that MDR infections may have on the outcome of liver transplant *** article reviews the current literature regarding the incidence and outcome of MDR infections in liver transplant recipients,and summarizes current preventive and therapeutic recommendations.

关键词： Multidrug resistance Bacterial infections Organ transplantation Methicillin-resistant Staphylococcus aureus Liver transplantation

Effects of Yerba Mate Consumption (Ilex paraguariensis) on Cardiac Remodeling in Rats

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Food and Nutrition Sciences 2024年第8期15卷 827-845页

作者： Carlos Eduardo Brochini de Paiva Thaíssa Baptista Brochini de Paiva Isabelle Tiburcio Pecin Ferreira Sandra Cristina Genaro Danilo Silva Martins Santos Thaoan Bruno Mariano Robson Chacon Castoldi Rafael Stuani Floriano julia Amanda Rodrigues Fracasso Lucas Pires Guarnier Marina Politi Okoshi Francis lopes Pacagnelli Postgraduate Program in Health Sciences Unoeste Presidente Prudente Brazil Faculty of Medicine Unoeste Presidente Prudente Brazil Department of Physiotherapy Unoeste Presidente Prudente Brazil Department of Nutrition Unoeste Presidente Prudente Brazil Postgraduate Program in Science and Movement Unesp Rio Claro Brazil Postgraduate Program in Health Promotion University of Northern Paran (UNOPAR) Londrina Brazil School of Dentistry So Paulo State University (UNESP) Araatuba Brazil Department of Genetics Ribeiro Preto Medical School University of So Paulo USP Ribeiro Preto Brazil Internal Medicine Department Botucatu Medical School So Paulo State University (UNESP) Botucatu Brazil

This study investigated the effects of yerba mate consumption, a South American beverage, on cardiac remodeling in rats. For this purpose, 24 male Wistar rats were divided into Control Group (CG) which received filtered water and a standard diet, and Yerba Mate Group (YM), 6 g of Ilex paraguariensis in 100 ml water and the same diet, for 30 days. The YM group showed a reduction in final body weight and food consumption without altering weight gain. Regarding cardiac remodeling, the YM group exhibited a decrease in the right ventricle weight/final body weight ratio, suggesting cardiac atrophy, without affecting the atria and left ventricle. There was no change in cardiomyocyte area or nuclear fractal dimension in both groups. However, animals that consumed yerba mate showed increased collagen deposition and a smaller fractal dimension in the left ventricle. The consumption of yerba mate at room temperature for 30 days induced changes in cardiac remodeling, as evidenced by increased collagen deposition and alterations in fractal dimension in the left ventricle.

关键词： Tereré Ilex paraguariensis Yerba Mate Cardiac Remodeling Fractal Dimension Hypertrophy

Traits associated with winter wheat grain yield in Central and West Asia

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journal of Integrative Plant Biology 2014年第7期56卷 673-683页

作者： Marta Silva lopes Didem Saglam Mutlu Ozdogan Matthew Reynolds CIMMYT University of Ahi Evran Faculty of Agriculture Department of Plant Protection Center for Sustainability and the Global Environment University of Wisconsin‐Madison

Improved adaptation of winter wheat （Triticum aestivum L.） to drought and heat may be influenced by days to heading, plant height, biomass, canopy temperature （CT） at grain fil ing, and rate of senescence. This study shows that, under supplemental irrigation or rainfed conditions, days to heading and plant height together explain up to 68%of grain yield （GY） variation, and these associations were further confirmed in several locations across West and Central Asia. Days to heading can be slightly reduced below that of check line Karahan to further improve GY while avoiding the effect of late frosts. Plant height has been decreased in recent germplasm, but further reductions below that of check line Karahan could stil improve GY in a wide range of environ-ments. However, in Iranian sites, tal er genotypes showed better adaptation with higher biomass and increased reserves＆amp;nbsp;for grain fil ing. Canopy temperature and rate senescence were not associated with GY. A normalized difference vegetation index, used to estimate biomass （Feekes stages 4-5）, had intermediate heritability across environments and correlated positively with GY under low plant density and should be explored further as a tool for early selection.

关键词： Biomass GxE earliness phenology plant height NDVI rain-fed yield

Formation of DNA Strand Breaks in Peripheral Lymphocytes of Rats After Exposure to Natural Sunlight

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Biomedical and Environmental Sciences 2012年第2期25卷 245-249页

作者： Dorival Mendes RODRIGUES-jUNIOR Ana Amélia de CARVALHO MELO Benedito Borges da SILVA Pedro Vitor lopes-COSTA Department of Biology Federal University of Piaui-TeresinaPiauiBrazil Department of Gynecology Federal University of Piaui-TeresinaPiauiBrazil

Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil（5oS,42oW）.Materials and Methods Thirty Wistar-Hannover rats,three months old,were randomly divided into three groups of 10 animals each：Group I [control,without exposure to ultraviolet（UV） radiation],Group II（exposed to sunlight during 08：00 *** 10：00 a.m.）,and Group III（exposed to sunlight during 10：00 *** 12：00 a.m.）.After a week of exposure,peripheral blood samples were taken from the tail of these animals to prepare smears on two slides per *** 24 h after exposure to sunlight in Group III,a new collection was obtained to observe the repair *** alkaline comet assay was used in this study to evaluate the genotoxic activity of sunlight（P0.05）.Results There was no statistical difference between Group I and II（P=0.672）.On the other hand,the exposure to sunlight in Group III showed genotoxic action in comparison to the other groups（P0.0001）.Also,there was no significant repair in Group III R（P=0.407）.Conclusion This study has shown a genotoxic potential of sunlight（UVA-B） in lymphocytes of mammals from 10：00 *** 12：00 a.m.,due to a higher intensity of UV in this tropical region.

关键词： Comet assay DNA damage Rats Sunlight Ultraviolet radiation

Using dung beetles to evaluate the effects of urbanization on Atlantic Forest biodiversity

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Insect Science 2013年第3期20卷 393-406页

作者： Vanesca Korasaki jose lopes George Gardner Brown julio Louzada Departamento de Agronomia Departamento de Biologia Animal e Vegetal Universidade Estadual de Londrina Londrina-PR Empresa Brasileira de Pesquisa Agropecu~ria Embrapa Florestas Colombo-PR Departamento de Biologia Setor de Ecologia Universidade Federal de Lavras Lavras Minas Gerais Brazil

We used dung beetles to evaluate the impact of urbanization on insect biodi- versity in three Atlantic Forest fragments in Londrina, Parana, Brazil. This study provides the first empirical evidence of the impact of urbanization on richness, abundance, compo- sition and guild structure of dung beetle communities from the Brazilian Atlantic Forest. We evaluated the community aspects （abundance, richness, composition and food guilds） of dung beetles in fragments with different degrees of immersion in the urban matrix using pitfall traps with four alternative baits （rotten meat, rotten fish, pig dung and decaying ba- nana）. A total of 1 719 individuals were collected, belonging to 29 species from 11 genera and six Scarabaeinae tribes. The most urban-immersed fragment showed a higher species dominance and the beetle community captured on dung presented the greatest evenness. The beetle communities were distinct with respect to the fragments and feeding habits. Except for the dung beetle assemblage in the most urbanized forest fragment, all others exhibited contrasting differences in species composition attracted to each bait type. Our results clearly show that the degree of urbanization affects Atlantic Forest dung beetle communities and that the preservation of forest fragments inside the cities, even small ones, can provide refuges for Scarabaeinae.

关键词： bioindicator coprophagous beetles food preference fragmentation habitat loss urban matrix