Near real-time security system applied to SDN environments in IoT networks using convolutional neural network

[EN] The Internet of Things (IoT) paradigm brings new and promising possibilities for services and products. The heterogeneity of IoT devices highlights the inefficiency of traditional networks' structures to support their specific requirements due to their lack of flexibility. Thus, Software-defined Networking (SDN) is commonly associated with IoT since this architecture provides a more flexible and manageable network environment. As shown by recent events, IoT devices may be used for large scale Distributed Denial of Service (DDoS) attacks due to their lack of security. This kind of attack is commonly detected and mitigated at the destination-end network but, due to the massive volume of information that IoT botnets generate, this approach is becoming impracticable. We propose in this paper a near real-time SDN security system that both prevents DDoS attacks on the source-end network and protects the sources SDN controller against traffic impairment. For this, we apply and test a Convolutional Neural Network (CNN) for DDoS detection, and describe how the system could mitigate the detected attacks. The performance outcomes were performed in two test scenarios, and the results pointed out that the proposed SDN security system is promising against next-generation DDoS attacks. (C) 2020 Published by Elsevier Ltd.This study was financed in part by the National Council for Scientific and Technological Development (CNPq) of Brazil under Grants 310668/2019-0 and 309335/2017-5; by the Ministerio de Economia y Competitividad in the "Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia, Subprograma Estatal de Generacion de Conocimiento" within the project under Grant TIN2017-84802-C2-1-P; by FCT/MCTES through national funds and when applicable co-funded EU funds under the Project UIDB/EEA/50008/2020; and by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) by the granting of a scholarship through the "Programa de Doutorado Sanduche no Exterior (PDSE) 2019". Finally, this work was supported by Federal University of Parana(UFPR) under Project Banpesq/2014016797.De Assis, MVO.; Carvalho, LF.; Rodrigues, JJPC.; Lloret, J.; Proenca Jr, ML. (2020). Near real-time security system applied to SDN environments in IoT networks using convolutional neural network. Computers & Electrical Engineering. 86:1-16. https://doi.org/10.1016/j.compeleceng.2020.1067381168

Genomic Analyses, Gene Expression and Antigenic Profile of the Trans-Sialidase Superfamily of Trypanosoma cruzi Reveal an Undetected Level of Complexity

The protozoan parasite Trypanosoma cruzi is the etiologic agent of Chagas disease, a highly debilitating human pathology that affects millions of people in the Americas. The sequencing of this parasite's genome reveals that trans-sialidase/trans-sialidase-like (TcS), a polymorphic protein family known to be involved in several aspects of T. cruzi biology, is the largest T. cruzi gene family, encoding more than 1,400 genes. Despite the fact that four TcS groups are well characterized and only one of the groups contains active trans-sialidases, all members of the family are annotated in the T. cruzi genome database as trans-sialidase. After performing sequence clustering analysis with all TcS complete genes, we identified four additional groups, demonstrating that the TcS family is even more heterogeneous than previously thought. Interestingly, members of distinct TcS groups show distinctive patterns of chromosome localization. Members of the TcSgroupII, which harbor proteins involved in host cell attachment/invasion, are preferentially located in subtelomeric regions, whereas members of the largest and new TcSgroupV have internal chromosomal locations. Real-time RT-PCR confirms the expression of genes derived from new groups and shows that the pattern of expression is not similar within and between groups. We also performed B-cell epitope prediction on the family and constructed a TcS specific peptide array, which was screened with sera from T. cruzi-infected mice. We demonstrated that all seven groups represented in the array are antigenic. A highly reactive peptide occurs in sixty TcS proteins including members of two new groups and may contribute to the known cross-reactivity of T. cruzi epitopes during infection. Taken together, our results contribute to a better understanding of the real complexity of the TcS family and open new avenues for investigating novel roles of this family during T. cruzi infection

Forest disturbance and growth processes are reflected in the geographical distribution of large canopy gaps across the Brazilian Amazon

Canopy gaps are openings in the forest canopy resulting from branch fall and tree mortality events. The geographical distribution of large canopy gaps may reflect underlying variation in mortality and growth processes. However, a lack of data at the appropriate scale has limited our ability to study this relationship until now. We detected canopy gaps using a unique LiDAR dataset consisting of 650 transects randomly distributed across 2500 km(2) of the Brazilian Amazon. We characterized the size distribution of canopy gaps using a power law and we explore the variation in the exponent, alpha. We evaluated how the alpha varies across the Amazon, in response to disturbance by humans and natural environmental processes that influence tree mortality rates. We observed that South-eastern forests contained a higher proportion of large gaps than North-western, which is consistent with recent work showing greater tree mortality rates in the Southeast than the Northwest. Regions characterized by strong wind gust speeds, frequent lightning and greater water shortage also had a high proportion of large gaps, indicating that geographical variation in alpha is a reflection of underlying disturbance processes. Forests on fertile soils were also found to contain a high proportion of large gaps, in part because trees grow tall on these sites and create large gaps when they fall; thus, canopy gap analysis picked up differences in growth as well as mortality processes. Finally, we found that human-modified forests had a higher proportion of large gaps than intact forests, as we would expect given that these forests have been disturbed. Synthesis. The proportion of large gaps in the forest canopy varied substantially over the Brazilian Amazon. We have shown that the trends can be explained by geographical variation in disturbance and growth. The frequency of extreme weather events is predicted to increase under climate change, and changes could lead to greater forest disturbance, which should be detectable as an increased proportion of large gaps in intact forests.Peer reviewe

Neuromuscular activity of bothrops fonsecai snake venom in vertebrate preparations

CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOThe neuromuscular activity of venom from Bothrops fonsecai, a lancehead endemic to southeastern Brazil, was investigated. Chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND) preparations were used for myographic recordings and mouse diaphragm muscle was used for membrane resting potential (RP) and miniature end-plate potential (MEPP) recordings. Creatine kinase release and muscle damage were also assessed. In CBC, venom (40, 80 and 160μg/ml) produced concentration- and time-dependent neuromuscular blockade (50% blockade in 85±9 min and 73±8 min with 80 and 160μg/ml, respectively) and attenuated the contractures to 110μM ACh (78-100% inhibition) and 40mM KCl (45-90% inhibition). The venom-induced decrease in twitch-tension in curarized, directly-stimulated preparations was similar to that in indirectly stimulated preparations. Venom (100 and 200μg/ml) also caused blockade in PND preparations (50% blockade in 94±13 min and 49±8 min with 100 and 200μg/ml, respectively) but did not alter the RP or MEPP amplitude. In CBC, venom caused creatine kinase release and myonecrosis. The venom-induced decrease in twitch-tension and in the contractures to ACh and K(+) were abolished by preincubating venom with commercial antivenom. These findings indicate that Bothrops fonsecai venom interferes with neuromuscular transmission essentially through postsynaptic muscle damage that affects responses to ACh and KCl. These actions are effectively prevented by commercial antivenom.The neuromuscular activity of venom from Bothrops fonsecai, a lancehead endemic to southeastern Brazil, was investigated. Chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND) preparations were used for myographic recordings and mouse diaphragm muscle was used for membrane resting potential (RP) and miniature end-plate potential (MEPP) recordings. Creatine kinase release and muscle damage were also assessed. In CBC, venom (40, 80 and 160mg/ml) produced concentration- and time-dependent neuromuscular blockade (50% blockade in 85±9 min and 73±8 min with 80 and 160mg/ml, respectively) and attenuated the contractures to 110mM ACh (78–100% inhibition) and 40mM KCl (45–90% inhibition). The venom-induced decrease in twitch-tension in curarized, directly-stimulated preparations was similar to that in indirectly stimulated preparations. Venom (100 and 200mg/ml) also caused blockade in PND preparations (50% blockade in 94±13 min and 49±8 min with 100 and 200mg/ml, respectively) but did not alter the RP or MEPP amplitude. In CBC, venom caused creatine kinase release and myonecrosis. The venom-induced decrease in twitch-tension and in the contractures to ACh and K+ were abolished by preincubating venom with commercial antivenom.These findings indicate that Bothrops fonsecai venom interferes with neuromuscular transmission essentially through postsynaptic muscle damage that affects responses to ACh and KCl. These actions are effectively prevented by commercial antivenom5615CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOsem informaçãosem informaçã

Taninos vegetais ou polifen?is

Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM

Autonomic thermoregulatory dysfunction in neurofibromatosis type 1 Disfunção autonômica termorregulatória na neurofibromatose do tipo 1

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder, caused by mutations in a single gene (OMIM #162200, neurofibromin, 17 q11.2) affecting the development-maintenance-repair of neural and cutaneous tissues. Neurofibromatosis type 1 is the most common human monogenetic disease (1:3000, affecting nearly 80,000 Brazilian people) and it exhibits marked phenotype expression variability and an unpredictable course 5 , and both features are related to life expectancy, and quality of life. Possible mechanisms involving NF1-reduced muscle strength and aerobic capacity could be neurological abnormalities related to the neurofibromin deficiency, such as poorer motor coordination/activation, as well as lower levels of daily physical activities and motivation for exercising. Both neural disorder and reduced aerobic capacity could adversely affect thermoregulatory capacity, leading to decreased exercise performance in hot environments and heat intolerance with higher risk for heat-related injuries 6 . Despite increases in environmental temperature and/or exercise body metabolism, human internal temperature must be maintained within a small physiological range through heat dissipation, to prevent tissue ABSTRACT Objective: Neurofibromatosis type 1 (NF1) causes neural and cutaneous disorders and reduced exercise capacity. Exercise/heat exposure increasing internal temperature must be compensated by eccrine sweat function and warmed skin vasodilation. We suspected NF1 could adversely affect eccrine sweat function and/or vascular thermoregulatory responses (VTR). Methods: The eccrine sweat function and VTR of 25 NF1 volunteers (14 males, 11 females; 16-57 years old) were compared with 23 non-NF1 controls matched by sex, age, height and weight (CG). Sweating was induced by 1) pilocarpine 1% iontophoresis (PILO); and 2) by passive heating (HEAT) via the lower third of the legs being immersed in 42°C water for one hour. Previously established eccrine sweat function and VTR protocols were used. Results: The NF1 group showed: a) lower sweat rate than the CG group during PILO; b) a smaller diastolic pressure decrease; and c) higher tympanic temperatures than controls during HEAT (p < 0.05). Conclusion: Reduced sweating and vascular thermoregulatory responses suggest autonomic dysfunction in NF1 individuals. Keywords: neurofibromatosis 1; sweating; primary dysautonomias; body temperature regulation. RESUMO Objetivo: Neurofibromatose do tipo 1 (NF1) causa problemas neurais e cutâneos e diminuição da capacidade física. O aumento da temperatura interna durante exercício e exposição ao calor precisa ser compensada pela função sudorípara écrina (FSE) e aquecimento cutâneo por vasodilatação (RVT). Suspeitou-se clinicamente que a NF1 poderia prejudicar a FSE e a RVT. Métodos: A FSE e RVT de 25 voluntários com NF1 (14 homens, 11 mulheres; 16-57 anos) e de 23 sem-NF1, emparelhados por sexo, idade, estatura e peso corporal, foram medidas com protocolos validados anteriormente. A sudorese foi induzida por iontoforese com pilocarpina (PILO) e aquecimento passivo por imersão das pernas em água a 42°C durante uma hora (HEAT). Resultados: O grupo NF1 apresentou menor taxa de sudorese na situação PILO, menor redução da pressão diastólica e maior temperatura timpânica na situação HEAT (p < 0.05). Conclusão: As respostas sudorípara e vascular reduzidas sugerem disfunção autonômica nas pessoas com NF1. Palavras-chave: neurofibromatose 1; sudorese; disautonomia primária; regulação da temperatura corporal

Educação para a cidadania: a função social da escola nas séries iniciais

A educação tem como finalidade a construção da cidadania. Na escola sua ação e reflexão poderá contribuir com uma educação emancipadora, onde os cidadãos e cidadãs descubram a sua real capacidade de perceber o mundo em que vive. A presente pesquisa tem como foco de interesse a “Educação Para a Cidadania: A função social da escola nas séries iniciais”; o tema dá ênfase à problemática investigada. “Como os professores da rede pública de Brasília Distrito federal, em sua prática pedagógica levam seus alunos a serem cidadãos e cidadãs, críticos e transformadores”. Percebe-se que, de um modo geral, os professores não têm claros os conhecimentos voltados à questão da cidadania, como um fator determinante na conscientização dos educandos. É fundamental que a escola caminhe para uma educação democrática e conscientizadora. Nesse sentido, o objetivo deste estudo foi verificar se, através da prática pedagógica, os professores levam seus alunos a terem uma postura crítica participativa ao longo do processo ensino-aprendizagem. A escola deve ser um espaço democrático onde permita ao aluno manifestar seus conhecimentos e experiências de vida, seja através da interação oral ou escrita. O professor, nesta perspectiva, deverá ser capaz de assegurar continuamente as conquistas dos alunos promovendo a interação dentro e fora da escola, a fim de construir uma consciência democrática em seus educandos. Em última análise, este trabalho não tem a pretensão de ser uma obra pronta e acabada, nem tão pouco esgotar o assunto, mas sim, contribuir para que a escola seja o principal fórum das futuras gerações, e os professores, aqueles cuja função possa plantar valores éticos e morais de democracia e de cidadania plena

Tolerância para resíduos de EBDCs em culturas com geração fitogênica de CS2.

Neste trabalho foram utilizados três métodos para análise de ditiocarbamatos em amostras testemunha de mamão das variedades Golden, Sunrise solo e Tainung. Os mamões foram cultivados em áreas experimentais sem utilização, durante todo o ciclo da cultura, de agrotóxicos ou fertilizantes sulfurados. O CS2 foi quantificado por espectrofotometria e por cromatografia gasosa utilizando detector fotométrico de chama no modo enxofre, tanto no método por headspace quanto por partição em iso-octano. Todos os métodos forneceram resultados positivos de CS2 no mamão, independentemente da variedade avaliada. As concentrações de CS2 observadas foram comparadas com o limite máximo de resíduos de etilenobis(ditiocarbamatos)(EBDCs), estabelecido na Comunidade Européia em 0,05mg kg-1. A probabilidade de ser encontrada uma amostra de mamão com concentração de CS2 igual ou acima de 0,05 mg kg-1 foi de 12 % pelo método de iso-octano, 55% pelo método de headspace e 94 % pelo método espectrofotométrico. Desse modo, os resíduos de EBDCs quantificados como CS2, devem ser cuidadosamente interpretados em culturas com geração fitogênica de CS2, pois a presença deste não confirma a utilização de fungicidas EBDCs

Comparative genomic analysis of Leishmania (Viannia) peruviana and Leishmania (Viannia) braziliensis

BACKGROUND: The Leishmania (Viannia) braziliensis complex is responsible for most cases of New World tegumentary leishmaniasis. This complex includes two closely related species but with different geographic distribution and disease phenotypes, L. (V.) peruviana and L. (V.) braziliensis. However, the genetic basis of these differences is not well understood and the status of L. (V.) peruviana as distinct species has been questioned by some. Here we sequenced the genomes of two L. (V.) peruviana isolates (LEM1537 and PAB-4377) using Illumina high throughput sequencing and performed comparative analyses against the L. (V.) braziliensis M2904 reference genome. Comparisons were focused on the detection of Single Nucleotide Polymorphisms (SNPs), insertions and deletions (INDELs), aneuploidy and gene copy number variations. RESULTS: We found 94,070 variants shared by both L. (V.) peruviana isolates (144,079 in PAB-4377 and 136,946 in LEM1537) against the L. (V.) braziliensis M2904 reference genome while only 26,853 variants separated both L. (V.) peruviana genomes. Analysis in coding sequences detected 26,750 SNPs and 1,513 indels shared by both L. (V.) peruviana isolates against L. (V.) braziliensis M2904 and revealed two L. (V.) braziliensis pseudogenes that are likely to have coding potential in L. (V.) peruviana. Chromosomal read density and allele frequency profiling showed a heterogeneous pattern of aneuploidy with an overall disomic tendency in both L. (V.) peruviana isolates, in contrast with a trisomic pattern in the L. (V.) braziliensis M2904 reference. Read depth analysis allowed us to detect more than 368 gene expansions and 14 expanded gene arrays in L. (V.) peruviana, and the likely absence of expanded amastin gene arrays. CONCLUSIONS: The greater numbers of interspecific SNP/indel differences between L. (V.) peruviana and L. (V.) braziliensis and the presence of different gene and chromosome copy number variations support the classification of both organisms as closely related but distinct species. The extensive nucleotide polymorphisms and differences in gene and chromosome copy numbers in L. (V.) peruviana suggests the possibility that these may contribute to some of the unique features of its biology, including a lower pathology and lack of mucosal development. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1928-z) contains supplementary material, which is available to authorized users

Resíduos de EBDCs e culturas com geração fitogênica de CS2.

A análise de resíduos etilenobis(ditiocarbamatos) (EBDCs) é realizada de maneira indireta, pela dosagem de CS2. Desse modo, plantas que geram fitogenicamente CS2, como as Caricaceas, podem fornecer resultados falso positivos. Todos os métodos de análise de resíduos de EBDCs são uma variação do método de Keppel (1969; 1971), que dosa o CS2 colorimetricamente. O CS2 também pode ser analisado por cromatografia gasosa, utilizando-se a técnica de análise por headspace, ou pela modificação desse método com a dissolução do CS2 em uma camada de solvente orgânico (iso-octano). O objetivo deste estudo foi analisar em amostras testemunha de mamão o nível de CS2 endógeno por três métodos distintos de análise de resíduos de EBDCs: iso-octano, headspace e espectrofotométrico. As concentrações de CS2 foram comparadas com o limite máximo de resíduos adotado pela União Européia (0,05 mg kg-1)