4,583 research outputs found
Enhancing data security in cloud using random pattern fragmentation and a distributed nosql database
© 2019 IEEE. The cloud computing model has become very popular among users, as it has proven to be a cost-effective solution to store and process data, thanks to recent advancements in virtualization and distributed computing. Nevertheless, in the cloud environment, the user entrusts the safekeeping of its data entirely to the provider, which introduces the problem of how secure such data is and whether its integrity has been maintained. This paper proposes an approach to the data security in cloud by utilizing a random pattern fragmentation algorithm and combining it with a distributed NoSQL database. This not only increases the security of the data by storing it in different nodes and scramble all the bytes, but also allows the user to implement an alternative method of securing data. The performance of the approach is compared to other approaches, along with AES 256 encryption. Results indicate a significant performance improvement over encryption, highlighting the capabilities of this method for cloud stored data, as it creates a layer of protection without additional overhead
Encontros de ensino religioso nas cidades de Ouro Preto e Mariana : a laicidade da educa??o p?blica em quest?o.
Programa de P?s-Gradua??o em Educa??o. Departamento de Educa??o, Instituto de Ci?ncias Humanas e Sociais, Universidade Federal de Ouro Preto.Esta pesquisa teve como objetivo investigar como a laicidade do Estado brasileiro e a diversidade religiosa eram tratadas nos Encontros de Metodologia e Filosofia de Ensino Religioso nas cidades de Ouro Preto e Mariana, oferecidos pela parceria entre a Secretaria de Estado da Educa??o, por meio da Superintend?ncia Regional de Ensino (SRE) de Ouro Preto, e a Arquidiocese de Mariana. Abertos aos professores de ensino religioso das redes p?blica e privada, orienta??es e materiais pedag?gicos eram socializados nas reuni?es com o objetivo de fornecer conte?dos a serem trabalhados em sala de aula. A metodologia adotada na investiga??o foi a an?lise qualitativa, por meio de pesquisa documental, observa??o-participante, entrevista semiestruturada e question?rio, com o objetivo de identificar a proposta pedag?gica utilizada nas reuni?es, compreender e analisar como a diversidade religiosa era abordada durante esses eventos e compreender como se estabelecia o conceito de Estado laico na parceria estabelecida entre Estado e Igreja Cat?lica. Os resultados da pesquisa mostraram que houve significativa influ?ncia do cristianismo nos Encontros de Metodologia e Filosofia do Ensino Religioso, considerando a forte presen?a crist? nos materiais pedag?gicos socializados nas reuni?es, a aus?ncia de l?deres religiosos n?o crist?os nos eventos de capacita??o e a falta de acompanhamento n?o sistem?tico por parte do Estado. Soma-se a tais quest?es os espa?os de realiza??o das reuni?es, ligados ? Igreja Cat?lica, marcados por s?mbolos e significados religiosos. A diversidade religiosa n?o foi respeitada, e o Estado n?o cumpriu seu papel de regular as pr?ticas pedag?gicas nos Encontros de Metodologia e Filosofia do Ensino Religioso nas cidades de Mariana e Ouro Preto, evitando que uma ?nica religi?o fosse privilegiada.This research aimed to investigate how the secularity of Brazilian state and the religious diversity were dealt in the Methodology and Philosophy of Religious Education Meetings in the towns of Ouro Preto and Mariana, offered by the partnership between the State Department of Education, through the Superintendent Regional Education (SRE) in Ouro Preto, and the Archdiocese of Mariana. Open to teachers of religious education from public and private schools, guidelines and pedagogical materials were socialized in the meetings with the objective of providing content to be learned in the classroom. The methodology adopted in the study was the qualitative analysis, through documentary research, participant observation, semi-structured interviews and questionnaire, in order to identify the pedagogical proposal used in meetings, to understand and to analyze how religious diversity was addressed during these events and to understand how the concept of the Secularity State in the partnership between the State and the Catholic Church was established. The research results showed that there was significant influence of Christianity in Methodology and Philosophy of Religious Education Meetings, considering the strong Christian presence in the socialized pedagogical materials in the meetings, the absence of non-Christian religious leaders in the fundraising events and the lack of non-systematic monitoring by the State. It is added to these issues the spaces of the meetings, linked to the Catholic Church, marked by religious symbols and meanings. Religious diversity was not respected, and the State did not fulfill its role of regulating the pedagogical practices in Methodology and Philosophy of Religious Education Meetings in the towns of Ouro Preto and Mariana, preventing that a single religion was privileged
Mesoscopic spin confinement during acoustically induced transport
Long coherence lifetimes of electron spins transported using moving potential
dots are shown to result from the mesoscopic confinement of the spin vector.
The confinement dimensions required for spin control are governed by the
characteristic spin-orbit length of the electron spins, which must be larger
than the dimensions of the dot potential. We show that the coherence lifetime
of the electron spins is independent of the local carrier densities within each
potential dot and that the precession frequency, which is determined by the
Dresselhaus contribution to the spin-orbit coupling, can be modified by varying
the sample dimensions resulting in predictable changes in the spin-orbit length
and, consequently, in the spin coherence lifetime.Comment: 10 pages, 2 figure
Physical Activity Characteristics across GOLD Quadrants Depend on the Questionnaire Used
BACKGROUND:The GOLD multidimensional classification of COPD severity combines the exacerbation risk with the symptom experience, for which 3 different questionnaires are permitted. This study investigated differences in physical activity (PA) in the different GOLD quadrants and patient's distribution in relation to the questionnaire used. METHODS:136 COPD patients (58±21% FEV1 predicted, 34F/102M) completed COPD assessment test (CAT), clinical COPD questionnaire (CCQ) and modified Medical Research Council (mMRC) questionnaire. Exacerbation history, spirometry and 6MWD were collected. PA was objectively measured for 2 periods of 1 week, 6 months apart, in 5 European centres; to minimise seasonal and clinical variation the average of these two periods was used for analysis. RESULTS:GOLD quadrants C+D had reduced PA compared with A+B (3824 [2976] vs. 5508 [4671] steps.d-1, p<0.0001). The choice of questionnaire yielded different patient distributions (agreement mMRC-CAT κ = 0.57; CCQ-mMRC κ = 0.71; CCQ-CAT κ = 0.72) with different clinical characteristics. PA was notably lower in patients with an mMRC score ≥2 (3430 [2537] vs. 5443 [3776] steps.d-1, p <0.001) in both the low and high risk quadrants. CONCLUSIONS:Using different questionnaires changes the patient distribution and results in different clinical characteristics. Therefore, standardization of the questionnaire used for classification is critical to allow comparison of different studies using this as an entry criterion. CLINICAL TRIAL REGISTRATION:ClinicalTrials.gov NCT01388218
Laicidade da educa??o em quest?o : encontros de ensino religioso nas cidades de Ouro Preto e Mariana.
Baseado em recorte de pesquisa desenvolvida no Programa de P?s-Gradua??o em Educa??o apresentado ? Universidade Federal de Ouro Preto, o estudo investigou como a laicidade do Estado brasileiro e a diversidade religiosa foram abordadas nos Encontros de Metodologia e Filosofia de Ensino Religioso nas tricenten?rias cidades de Ouro Preto e Mariana (MG). A forma??o era oferecida aos professores de ensino religioso das redes p?blica e privada pela Secretaria de Estado da Educa??o/SRE Ouro Preto e Arquidiocese de Mariana. Adotou-se an?lise qualitativa, pesquisa documental, observa??o-participante, entrevista semiestruturada e question?rios para identificar a proposta pedag?gica das reuni?es e compreender e analisar como a diversidade religiosa e o conceito de Estado laico eram abordados. Os resultados mostraram que a diversidade religiosa n?o foi respeitada, o Estado n?o regulou tais pr?ticas pedag?gicas e que as forma??es podem ser consideradas inadequadas para forma??o de professores, considerando os princ?pios da escola p?blica e laica.Based on part of a research carried cut in the Graduate Program in Education presented to the Federal University of Ouro Preto, the study investigated how the secular nature of the Brazilian State and religious diversity were addressed in the Methodology Meetings and Religious Teaching of Philosophy in the three hundred years cities of Ouro Preto and Mariana (MG). The training was offered to religious education teachers in public and private schools by the Ministry of Education/SRE Ouro Preto and Mariana Archdiocese. It was adopted a qualitative analysis, documentary research, participant observation, semi-structured interviews and questionnaires to identify the pedagogical proposal of the meetings and understand and analyze how religious diversity and the concept of secular state were addressed. The results showed that religious diversity is not respected, the state did not regulate such teaching practices and that training may be considered inadequate teacher training, considering the principles of public and secular school
Structural power and the evolution of collective fairness in social networks
From work contracts and group buying platforms to political coalitions and international climate and economical summits, often individuals assemble in groups that must collectively reach decisions that may favor each part unequally. Here we quantify to which extent our network ties promote the evolution of collective fairness in group interactions, modeled by means of Multiplayer Ultimatum Games (MUG). We show that a single topological feature of social networks-which we call structural power-has a profound impact on the tendency of individuals to take decisions that favor each part equally. Increased fair outcomes are attained whenever structural power is high, such that the networks that tie individuals allow them to meet the same partners in different groups, thus providing the opportunity to strongly influence each other. On the other hand, the absence of such close peer-influence relationships dismisses any positive effect created by the network. Interestingly, we show that increasing the structural power of a network leads to the appearance of well-defined modules-as found in human social networks that often exhibit community structure-providing an interaction environment that maximizes collective fairness.This research was supported by Fundacao para a Ciencia e Tecnologia (FCT) through grants SFRH/BD/94736/2013, PTDC/EEI-SII/5081/2014, PTDC/MAT/STA/3358/2014 and by multi-annual funding of CBMA and INESC-ID (under the projects UID/BIA/04050/2013 and UID/CEC/50021/2013) provided by FCT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio
Subtidal macrozoobenthos communities from northern Chile during and post El Niño 1997–1998
Despite a large amount of climatic and oceanographic information dealing with the recurring climate phenomenon El Niño (EN) and its well known impact on diversity of marine benthic communities, most published data are rather descriptive and consequently our understanding of the underlying mechanisms and processes that drive community structure during EN are still very scarce. In this study, we address two questions on the effects of EN on macrozoobenthic communities: (1) how does EN affect species diversity of the communities in northern Chile? and (2) is EN a phenomenon that restarts community assembling processes by affecting species interactions in northern Chile? To answer these questions, we compared species diversity and co-occurrence patterns of soft-bottoms macrozoobenthos communities from the continental shelf off northern Chile during (March 1998) and after (September 1998) the strong EN event 1997–1998. The methods used varied from species diversity and species co-occurrence analyses to multivariate ordination methods.
Our results indicate that EN positively affects diversity of macrozoobenthos communities in the study area, increasing the species richness and diversity and decreasing the species dominance. EN represents a strong disturbance that affects species interactions that rule the species assembling processes in shallow-water, sea-bottom environments
Comparison of different methods for DNA-free RNA isolation from SK-N-MC neuroblastoma
<p>Abstract</p> <p>Background</p> <p>RNA quality and quantity are important factors for ensuring the accuracy of gene expression analysis and other RNA-based downstream applications. Extraction of high quality nucleic acids is difficult from neuronal cells and brain tissues as they are particularly rich in lipids. In addition, most common RNA extraction methods are phenol-based, resulting in RNA that may be incompatible with downstream applications such as gene expression.</p> <p>Findings</p> <p>In this work, a comparative analysis of the RNA quality obtained from SK-N-MC cells was performed using six commonly used RNA isolation kits: two phenol-based kits and four non-phenol based kits. The non-phenol based kits tested AxyPrep Multisource Total RNA Miniprep, RNeasy<sup>® </sup>Mini, EasySpin and Ilustra RNAspin Mini RNA Isolation, all performed well and resulted in the isolation of high quality RNA, as evaluated by A<sub>260</sub>/A<sub>280</sub>. The RNA extracted with AxyPrep Multisource Total RNA Miniprep, RNeasy<sup>® </sup>Mini and EasySpin provided the highest RNA yields. In particular, the RNA isolated by AxyPrep Multisource Total RNA Miniprep Kit did not show any detectable genomic DNA contamination even without previous DNase treatment or after RNA direct PCR amplification using universal 18S primers.</p> <p>Conclusions</p> <p>The RNA extracted from SK-N-MC cells with AxyPrep Multisource Total RNA Miniprep Kit was superior with respect to the RNA quality and concentration. This kit does not use aggressive organic solvents and RNA free of genomic DNA was isolated without the need for DNase treatment.</p
Zinc/copper imbalance reflects immune dysfunction in human leishmaniasis: an ex vivo and in vitro study
BACKGROUND: The process of elimination of intracellular pathogens, such as Leishmania, requires a Th1 type immune response, whereas a dominant Th2 response leads to exacerbated disease. Experimental human zinc deficiency decreases Th1 but not Th2 immune response. We investigated if zinc and copper levels differ in different clinical forms of leishmaniasis, and if these trace metals might be involved in the immune response towards the parasite. METHODS: Blood was collected from 31 patients with either localized cutaneous (LCL), mucosal (ML) or visceral (VL) leishmaniasis, as well as from 25 controls from endemic and non-endemic areas. Anti-Leishmania humoral and cellular immune response were evaluated by quantifying specific plasma IgG, lymphoproliferation and cytokine production, respectively. Plasma levels of Cu and Zn were quantified by atomic absorption spectrophotometry. RESULTS: A significant decrease in plasma Zn was observed in all three patient groups (p < 0.01 for LCL and ML, p < 0.001 for VL), as compared to controls, but only VL (7/10) and ML (1/7) patients displayed overt Zn deficiency. Plasma Cu was increased in LCL and VL (p < 0.001) but not in ML, and was strongly correlated to anti-Leishmania IgG (Spearman r = 0.65, p = 0.0028). Cu/Zn ratios were highest in patients with deficient cellular (VL<<LCL<ML) and exacerbated humoral (VL>LCL>ML) immune response. Ex vivo production of parasite-induced IFN-γ was negatively correlated to plasma Cu levels in LCL (r = -0.57, p = 0.01). In vitro, increased Cu levels inhibited IFN-γ production. CONCLUSIONS: 1. Zn deficiency in VL and ML indicate possible therapeutic administration of Zn in these severe forms of leishmaniasis. 2. Plasma Cu positively correlates to humoral immune response across patient groups. 3. Environmentally or genetically determined increases in Cu levels might augment susceptibility to infection with intracellular pathogens, by causing a decrease in IFN-γ production
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