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Tailored optical propulsion forces for controlled transport of resonant gold nanoparticles and associated thermal convective fluid flows

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Light(Science & Applications) 2020年第1期9卷 256-266页

作者： Jose A.rodrigo Mercedes Angulo Tatiana Alieva Facultad de Ciencias Fisicas Ciudad Universitaria s/nUniversidad Complutense de Madrid28040 MadridSpain

Noble metal nanoparticles illuminated at their plasmonic resonance wavelength turn into heat *** phenomenon has prompted the development of numerous applications in science and *** optical manipulation of such resonant nanoparticles could certainly extend the functionality and potential applications of optothermal *** this article,we experimentally demonstrate optical transport of single and multiple resonant nanoparticles(colloidal gold spheres of radius 200 nm)directed by tailored transverse phase-gradient forces propelling them around a 2d optical *** show how the phase-gradient force can be designed to efficiently change the speed of the *** have found that multiple hot nanoparticles assemble in the form of a quasi-stable group whose motion around the laser trap is also controlled by such optical propulsion *** assembly experiences a significant increase in the local temperature,which creates an optothermal convective fluid flow dragging tracer particles into the ***,the created assembly is a moving heat source controlled by the propulsion force,enabling indirect control of fluid flows as a micro-optofluidic *** existence of these flows,probably caused by the temperature-induced Marangoni effect at the liquid water/superheated water interface,is confirmed by tracking free tracer particles migrating towards the *** propose a straightforward method to control the assembly size,and therefore its temperature,by using a nonuniform optical propelling force that induces the splitting or merging of the group of *** envision further development of microscale optofluidic tools based on these achievements.

关键词： thermal fluid transport

Study of Branes with Variable Tension

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Communications in Theoretical Physics 2017年第11期67卷 595-599页

作者： rodrigo Aros Milko Estrada departamento de Ciencias Fisicas Universidad Andres Bello department of Physics Universidad de Antofagasta Instituto de Matematica Fisica y Estadistica Universidad de las Americas

In this work we study a brane world model with variable tension, which gives rise to four-dimensional cosmologies. The brane worlds obtained correspond to E?tv?s branes whose(internal) geometry can be casted as either a four-dimensional(A)dS_4 or a standard radiation period cosmology. The matter dominated period is discussed as well.

关键词： Randall–Sundrum brane world de Sitter hierarchy problem brane tension

Taxonomy for Privacy Policies of Social Networks Sites

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Social Networking 2013年第4期2卷 157-164页

作者： Sergio donizetti Zorzo rodrigo Pereira Botelho Paulo Muniz de ávila Computer Science department Federal University of Sao Carlos Sao Carlos Brazil

Social networking sites (SNSs) are becoming increasingly popular on the Web. Sharing personal information in these networks can be dangerous, considering that malicious users can get access to this information and use them for purposes other than the original. Although SNSs typically provide tools for users to set who can access their shared data, this access restriction only applies to network users and not for third parties and the social network itself. In this paper, we present both a mechanism to enhance privacy in SNSs and taxonomy for classifying SNSs privacy policies. We combine and extend two taxonomies of privacy, unifying them to classify SNSs privacy policies and also the aforemen-tioned mechanism. We evaluated the taxonomy classifying six SNSs privacy policies and the mechanism, presenting the results and our findings about the classification.

关键词： Security Privacy Policies Content Protection Privacy Taxonomy

Green economy and waste management: An inevitable plan for materials science

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Progress in Natural Science:Materials International 2022年第1期32卷 1-9页

作者： Suman Nandy Elvira Fortunato rodrigo Martins i3N/CENIMAT Department of Materials ScienceFaculty of Science and Technology Universidade NOVA de Lisboa and CEMOP/UNINOVA Campus de Caparica

Covid is giving us many lessons among which one must be to realize that this is the time to act for sustainable future. The smart world around us has made it inevitable to have an alarming situation regarding the uncontrolled growth of waste products such as plastic and electronic wastes. Both are immense threats to the health of human,wildlife and environment, that eventually affect the societal and economic structures as evident from recent Covid-crisis. The proper management of these wastes and innovating ideas for new sustainable technologies are the need of the hour. Circular economy act with green technology(green economy) is the way to tackle this challenge. Current perspective presents the overview of the scenario regarding these burgeoning issues and demonstrates some measures that are taken or being considered to depend on to come out of them.

关键词： Plastic waste management Medical waste management Electronic waste management Circular economy Green technology Sustainable world

Remote ischemic preconditioning as treatment for non-ischemic gastrointestinal disorders: Beyond ischemia-reperfusion injury

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World Journal of Gastroenterology 2014年第13期20卷 3572-3581页

作者： Carlos rodrigo Camara-Lemarroy departamento de Medicina Interna Hospital Universitario "Dr. José E. González"Universidad Autónoma de Nuevo LeónMonterreyNL 64460México

Common gastrointestinal diseases such as radiation enteritis(RE),acute pancreatitis,inflammatory bowel diseases(IBd)and drug-induced hepatotoxicity share pathophysiological mechanisms at the molecular level,mostly involving the activation of many pathways of the immune response,ultimately leading to tissue *** oxidative stress,inflammatory cytokine release,inflammatory cell infiltration and activation and the up-regulation of inflammatory transcription factors participate in the pathophysiology of these complex *** varies in each specific disease,but at least in the cases of RE and IBd immunosuppressors are ***,full therapeutic responses are not always *** pathophysiology of ischemiareperfusion(IR)injury shares many of these *** and repetitive periods of ischemia in an organ or limb have been shown to protect against subsequent major IR injury in distant organs,a phenomenon called remote ischemic preconditioning(RIP).This procedure has been shown to protect the gut,pancreas and liver by modulating many of the same inflammatory *** RIP is safe and tolerable,and has shown to be effective in some recent clinical trials,I suggest that RIP could be used as a physiologicallyrelevant adjunct treatment for non-ischemic gastrointestinal inflammatory conditions.

关键词： Ischemia reperfusion Ischemic preconditioning Remote ischemic preconditioning Acute pancreatitis Radiation enteritis Inflammatory bowel diseases Hepatotoxicity Inflammation

Interfacial Strategies for Smart Slippery Surfaces

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Journal of Bionic Engineering 2020年第4期17卷 633-643页

作者： Glen McHale rodrigo Ledesma-Aguilar Gary George Wells Smart Materials&Surfaces Laboratory Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon TyneNE18STUK

The problem of contact line pinning on surfaces is pervasive and contributes to problems from ring stains to ice *** we provide a single conceptual framework for interfacial strategies encompassing five strategies for modifying the solid-liquid interface to remove pinning and increase droplet *** biomimetic strategies are included,(i)reducing the liquid-solid interfacial area inspired by the Lotus effect,(ii)converting the liquid-solid contact to a solid-solid contact by the formation of a liquid marble inspired by how galling aphids remove honeydew,and(iii)converting the liquid-solid interface to a liquid-lubricant contact by the use of a lubricant impregnated surface inspired by the Nepenthes Pitcher *** further strategies are,(iv)converting the liquid-solid contact to a liquid-vapor contact by using the Leidenfrost effect,and(v)converting the contact to a liquid-liquid-like contact using slippery omniphobic covalent attachment of a liquid-like coating(SOCAL).Using these approaches,we explain how surfaces can be designed to have smart functionality whilst retaining the mobility of contact lines and ***,we show how droplets can evaporate at constant contact angle,be positioned using a Cheerios effect,transported by boundary reconfiguration in an energy invariant manner,and drive the rotation of solid components in a Leidenfrost heat *** conceptual framework enables the rationale design of surfaces which are slippery to liquids and is relevant to a diverse range of applications.

关键词： superhydrophobicity SLIPS liquid marbles leidenfrost SOCAL

Tree encroachment into savannas alters soil microbiological and chemical properties facilitating forest expansion

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Journal of Forestry Research 2016年第5期27卷 1047-1054页

作者： davi rodrigo Rossatto Everlon Cid Rigobelo departamento de Biologia Faculdade de Ciencias Agrairias e veterinàrias Univ. Estadual Paulista UNESP Via de Acesso Prof. Paulo Donatto Castellane S/N Vila IndustrialJaboticabal - SP 14884-900 Brazil departamento de Producao Vegetal Faculdade de Ciencias Agrairias e Veterinarias Univ. Estadual Paulista UNESP Viade Acesso Prof. Paulo Donatto Castellane S/N VilaIndustrial Jaboticabal - SP 14884-900 Brazil

Abstract Forests have been expanding over typical savanna sites for the past 3000 years in the Neotropics. Such invasion can produce a series of environmental modifications on typical savanna; however, it remains unclear how modifications in soil properties, caused by the encroachment of woody species, facilitate the expansion of forest ecosystems under dystrophic conditions. Here we examined chemical and microbiological changes associ- ated with tree encroachment in oxisols of a Neotropical Savanna at Assis Ecological Station, Southeastern Brazil. We predicted that tree encroachment caused by typical forest species would cause significant changes in the chemical and microbiological properties of savanna soils. Soils were sampled at Assis Ecological Station, from savanna sites differing in tree encroachment （typical, dense and forested savanna） caused by decades of fire exclusion. We analysed vegetation leaf area index and leaf litter volume deposited in the studied plots and chemical （pH,organic matter, P, K, Ca, Mg, A1, NO3-, NH4＋） and microbiological （microbial C biomass and dehydrogenase activity） properties of soils under distinct encroachment conditions. Most soil chemical properties did not change along the tree encroachment gradient; however, total P, soil organic matter, soil microbial C and dehydrogenase activity increased from typical savanna to forested savanna. The changes in soil organic matter and dehydrogenase activity were correlated with the values of leaf area index and litter volume along the encroachment gradient. Our results demonstrate that forest species can increase carbon and phosphorus supplies in tropical savanna soils.

关键词： dystrophic Encroachment - Forest - Litter Microbiological activity

On water security, sustainability, and the water-food-energy-climate nexus

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Frontiers of Environmental Science & Engineering 2013年第5期7卷 626-639页

作者： Michael Bruce BECK rodrigo VILLARROEL WALKER Wamell School of Forestry and Natural Resources University of Georgia Athens GA 30602-2152 USA

The role of water security in sustainable development and in the nexus of water, food, energy and climate interactions is examined from the starting point of the definition of water security offered by Grey and Sadoff. Much about the notion of security has to do with the presumption of scarcity in the resources required to meet human needs. The treatment of scarcity in mainstream economics is in turn examined, therefore, in relation to how each of us as individuals reconciles means with ends, a procedure at the core of the idea of sustainable development. According to the Grey-Sadoff definition, attaining water security amounts to achieving basic, single- sector water development as a precursor of more general, self-sustaining, multi-sectoral development. This is con- sistent with the way in which water is treated as ＂first among equals＂, i.e. privileged, in thinking about what is key in achieving security around the nexus of water, food, energy and climate. Cities, of course, are locations where demands for these multiple resource-energy flows are increasingly being generated. The paper discusses two important facets of security, i.e., diversity of access to resources and services （such as sanitation） and resilience in the behavior of coupled human-built-natural systems. Eight quasi-operational principles, by which to gauge nexus security with respect to city buildings and infrastructure, are developed.

关键词： cities as forces for good diversity energy and nutrient recovery green economy infrastructure failure,resilience

Nexus security： governance, innovation and the resilient city

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Frontiers of Environmental Science & Engineering 2013年第5期7卷 640-657页

作者： Michael Bruce BECK rodrigo VILLARROEL WALKER Wamell School of Forestry and Natural Resources University of Georgia Athens GA 30602-2152 USA

Nexus security is a compound mix of ideas： reconciling human needs and wants with access to multiple resources; diversity of access to those resources and services; resilience in the face of weather- and climate- related variability; resilience likewise in the face of infrastructure failure; and the personal, individual sense of belonging. At the level of Systems Thinking there is a very close relationship between resilience in the behavior of natural （ecological） systems and resilience in the social dynamics of governance within communities, where such resilience establishes the viability of these communities over centuries, which in turn entails successful stewardship of the man-environment relationship. We use insights from this cross-system mapping -- across natural, built, and human systems -- to assess, first, the role of city governance in achieving nexus security （or not） and, second, the role of technological innovations in serving the same purpose. More specifically, eight principles, covering resilience and diversity of access to resources and services, are used to gauge security-enhancing features of city buildings and infrastructure. Case studies include new designs of resilient office blocks, nutrient （nitrogen and phosphorus） recovery systems for sanitation and waste- water treatment, and the reconstruction of urban parks for the provision of ecosystem services. Throughout the paper, matters of risk in the face of meteorological variability are prominent. We do not conclude, however, that the presence of risk implies nexus insecurity.

关键词： cities as forces for good climate variability,ecosystem services energy and nutrient recovery infrastructure failure urban metabolism