2,767 research outputs found
Exploiting double exchange Diels-Alder cycloadditions for immobilization of peptide nucleic acids on gold nanoparticles
The generation of PNA-decorated gold nanoparticles (AuNPs) has revealed to be more difficult as compared to the generation of DNA-functionalized ones. The less polar nature of this artificial nucleic acid system and the associated tendency of the neutral poly-amidic backbone to aspecifically adsorb onto the gold surface rather than forming a covalent bond through gold-thiol interaction, combined with the low solubility of PNAs itself, form the main limiting factors in the functionalization of AuNP. Here, we provide a convenient methodology that allows to easily conjugate PNAs to AuNP. Positively charged PNAs containing a masked furan moiety were immobilized via a double exchange Diels-Alder cycloaddition onto masked maleimide-functionalized AuNPs in a one-pot fashion. Conjugated PNA strands retain their ability to selectively hybridize with target DNA strands. Moreover, the duplexes resulting from hybridization can be detached through a retro-Diels-Alder reaction, thus allowing straightforward catch-and-release of specific nucleic acid targets
Transparent Orchestration of Task-based Parallel Applications in Containers Platforms
This paper presents a framework to easily build and execute parallel applications in container-based distributed computing platforms in a user-transparent way. The proposed framework is a combination of the COMP Superscalar (COMPSs) programming model and runtime, which provides a straightforward way to develop task-based parallel applications from sequential codes, and containers management platforms that ease the deployment of applications in computing environments (as Docker, Mesos or Singularity). This framework provides scientists and developers with an easy way to implement parallel distributed applications and deploy them in a one-click fashion. We have built a prototype which integrates COMPSs with different containers engines in different scenarios: i) a Docker cluster, ii) a Mesos cluster, and iii) Singularity in an HPC cluster. We have evaluated the overhead in the building phase, deployment and execution of two benchmark applications compared to a Cloud testbed based on KVM and OpenStack and to the usage of bare metal nodes. We have observed an important gain in comparison to cloud environments during the building and deployment phases. This enables better adaptation of resources with respect to the computational load. In contrast, we detected an extra overhead during the execution, which is mainly due to the multi-host Docker networking.This work is partly supported by the Spanish Government through Programa Severo Ochoa (SEV-2015-0493), by the Spanish Ministry of Science and Technology through TIN2015-65316 project, by the Generalitat de Catalunya under contracts 2014-SGR-1051 and 2014-SGR-1272, and by the European Union through the Horizon 2020 research and innovation program under grant 690116 (EUBra-BIGSEA Project). Results presented in this paper were obtained using the Chameleon testbed supported by the National Science Foundation.Peer ReviewedPostprint (author's final draft
Would the combination of everolimus with endocrine-therapy help in FGFR2 positive serous endometrial cancer?
N/
Identifying and Classifying, Quantifying and Visualizing Green Infrastructure via Urban Transects in Rome, Italy and Sydney, Australia
Green Infrastructure is increasingly recognised as an approach to deliver a wide-ranging set of ecosystem services in cities and to operationalize concepts of urban resilience through the better delivery of urban planning, water sensitive urban design and a broad diversity of open space types. This paper argues that the first step in the delivery of effective Green Infrastructure planning and hence ecosystem services is the identification, visualisation and calculus of the full spectrum of existing open space types within urban contexts. To test this idea two case study cities – Rome and Sydney – were selected for their differing geographical origins and planning history. In each city an analysis of the urban fabric through a novel transect mapping process revealed a range of Green Infrastructure types including a diversity of open space, public parks and plazas, streetscapes, greenways and terrain vague. This began by analysing and comparing identified land-uses with existing planning rules, strategies and mechanisms within each city. Through this process we found that for each city significant differences were evident between the formally recognised urban open space and a range of potential additional Green Infrastructure candidates were identified. We then considered the potential recognition and activation of these spaces as critical pieces of overlooked Green Infrastructure into the metrics of a sustainable future city. Comparing these two cities against each other also confirmed the richness of Green Infrastructure types globally across both expanding and contracting cities and highlights differences in data precision, land policy, governance, nomenclature and urban conditions. This research posits that in the absence of the holistic and multi-faceted understanding, metrification and the visualisation of the diversity and distribution of green infrastructure in all its forms then progress towards implementation of robust and resilient cities and their urban ecosystem services will be limited
Recommended from our members
Integrating Agriculture in Greenways: a Methodology for Planning Connected Urban and Peri-Urban Farmlands in a Mediterranean City
Cities are often threatened by a loss of environmental quality due the rapid increase of urbanized areas that fragment natural landscapes. This is particularly true at the cities’ fringe where uncontrolled urbanization is often characterized by discontinuous patterns and consequent fragmentation of farmlands. These phenomena are particularly relevant in Mediterranean cities, where the high degree of land-use transitions, a consequence of urban growth with poor environmental regulations produce urban landscapes characterized by a lack of green areas and high levels of ecological fragmentation (EEA, 2006).
Greenways are one of the most powerful and widespread tools used at urban, metropolitan and regional scales. Their aim is to counteract ecological fragmentation and to integrate urban development, nature conservation and public health promotion (Ahern, 1995; Fabos & Ryan, 2006). They facilitate linkages between rural and urban spaces along the rural-urban interface through linear systems (Walmsley, 2006). As networks of linear elements they are planned, designed and managed for multiple purposes, including the provision of ecosystem services such as purification of air and water, mitigation of floods, climate regulation, generation and renewal of soil fertility, accessibility to open spaces and intellectual stimulation. Urban contexts present particular challenges for greenways development due to the complex arrangement of urban landscape features. The large number and diversity of land-cover types often produce high degrees of fragmentation of open spaces and heterogeneity of their roles and functions. For this reason a number of different types of patches of Non Urbanized Areas (NUAs) are present in urban contexts: this calls for a characterization of these spaces in order to highlight their physical features and their ecological and social functions. Particularly, they could represent a big opportunity for planning policies oriented to support new forms of urban agriculture (La Greca et al., 2011a).
When formulating planning approaches to greenways in urban contexts, new forms of agriculture have been the focus of very few studies and applications but they can significantly contribute to cities’ sustainability (Zasada, 2011). Proposing an agricultural greenway that integrates different NUAs into a network of farmlands and other green spaces (parks, playgrounds and so on) could significantly improve the overall accessibility of these areas, redefining the rural-urban interface and enhancing the provision of urban ecosystem services
O Brasil na Literatura do século XIX
Considering literature as a favored representative source of historic narration, this research intends to analyze the social relationships established in Brazilian society in the XIXcentury and how these relationships contributed to the formation of national identity, by carrying out a critical analysis of the romances, MemĂłrias de um Sargento de MilĂcias(Memoirs of a Militia Sergeant), by Manuel AntĂ´nio de Almeida, Senhora (Madame), by JosĂ© de Alencar, and A MĂŁo e a Luva (The Hand and the Glove), by Machado de Assis, throughthe perspective of Cultural History.Considerando a Literatura enquanto fonte representativa privilegiada do relato histĂłrico, esta pesquisa tem o intuito de, por meio de uma análise crĂtica dos romances MemĂłrias de um Sargento de MilĂcias, de Manuel AntĂ´nio de Almeida, Senhora, de JosĂ© de Alencar, e A MĂŁo e a Luva, de Machado de Assis, sob a perspectiva da HistĂłria Cultural, analisar as relações sociais estabelecidas na sociedade brasileira do sĂ©culo XIX e como suas representações contribuĂram para a formação da identidade nacional
Graph methods in Multi Agent Systems Coordination and Social Network Analysis
In this thesis several results on two main topics are collected: the coordination of networked multi agents systems and the diffusion of innovation of social networks.
The results are organized in two parts, each one related with one of the two main topics.
The common aspect of all the presented problems is the following: all the system are represented by graphs.
Two are the main contributions of the first part.
• A formation control strategy, based on gossip, which leads a set of autonomous vehicles to converge to a desired spatial disposition in absence of a common reference frame. If the vehicles have common direction, we prove that the proposed algorithm is robust against noise on displacement measurement.
• \item The formalization of the Heterogeneous Multi Vehicle Routing Problem, which can be described as follows: given an heterogeneous set of mobile robots, and a set of task to be served randomly displaced in a 2D environment, find the optimal task assignment to minimize the service cost. We firstly characterize the optimal centralized solution, and then we propose two distributed algorithms, based on gossip, which lead the system to a sub-optimal solutions and are significantly computationally more efficient than the optimal one.
The contributions of the second part are the following.
• We study how the innovation spreads in a Social Network according to the so called Linear Threshold Model, in which the innovation is incepted in the network starting from a seed set, and nodes adopt the innovation if the ratio of the neighbours that have already adopted it is greater than or equal a certain threshold value. We focus on the cohesive subset of the network, which can be used to compute the set of final adopters. If a set is cohesive and none of the nodes have adopted the innovation at a certain time , then they are not able to adopt the innovation at any . We propose an algorithm based on linear programming which computes the maximal cohesive subset of the complement of the seed set.
• According to the Linear Threshold Model, we define two problem of interest in Social Networks analysis and characterize the optimal solution: the Influence Maximization Problem in Finite Time and the diffusion of innovation over a target set.
• We characterize the novel Non Progressive Linear Threshold Model, which extends the classical Linear Threshold Model. We formalize the model and we give a characterization of the network dynamics in terms of cohesive and persistent set
Dos “comejeres” a “gusanitos desnudos”: o fazer literário como problema em Luvina, de Juan Rulfo
This article is intended to reflect on the story "Luvina”, published in 1953, from what the states: its form. So it starts with the dual narration, the formation of two environments, one of the sentence and another the utterance, in order to understand how to tell the complicated relationship between literary form and social process.Este artigo tem por objetivo refletir sobre o conto “Luvina”, publicado em 1953, a partir daquilo que a especifica: sua forma. Assim, parte-se da dupla narração, da formação de dois ambientes, um do enunciado e outro da enunciação, a fim de compreender como se dá no conto a complicada relação entre forma literária e processo social.  
Evaluating The Potential Energy Savings Of An Urban Green Infrastructure Through Environmental Simulation
Green infrastructure is a very important aspect to be considered in designing and preparing cities to adapt and mitigate climate change impacts on the built environment. Green based solutions have a strong impact on many aspects, such as controlling storm-water, reducing urban heat island effect, stabilizing soils, facing earthquakes, etcetera. In this paper an environmental analysis is performed by simulation with TRNSYS Studio tool. The cooling potential that can be obtained by trees in residential compounds is assessed, considering shadowing effect, changes in air movement, sky view factor reduction and other simulation-parameter changes. Results show that a reduction of 30 to 50% in cooling demand can be obtained by using a raw of trees on South, East and especially West façades. Two types of trees are tested, showing different cooling performances depending on the height and form of the trees
- …