An IoT-Focused Intrusion Detection System Approach Based on Preprocessing Characterization for Cybersecurity Datasets.

Security in IoT networks is currently mandatory, due to the high amount of data that has to be handled. These systems are vulnerable to several cybersecurity attacks, which are increasing in number and sophistication. Due to this reason, new intrusion detection techniques have to be developed, being as accurate as possible for these scenarios. Intrusion detection systems based on machine learning algorithms have already shown a high performance in terms of accuracy. This research proposes the study and evaluation of several preprocessing techniques based on traffic categorization for a machine learning neural network algorithm. This research uses for its evaluation two benchmark datasets, namely UGR16 and the UNSW-NB15, and one of the most used datasets, KDD99. The preprocessing techniques were evaluated in accordance with scalar and normalization functions. All of these preprocessing models were applied through different sets of characteristics based on a categorization composed by four groups of features: basic connection features, content characteristics, statistical characteristics and finally, a group which is composed by traffic-based features and connection direction-based traffic characteristics. The objective of this research is to evaluate this categorization by using various data preprocessing techniques to obtain the most accurate model. Our proposal shows that, by applying the categorization of network traffic and several preprocessing techniques, the accuracy can be enhanced by up to 45%. The preprocessing of a specific group of characteristics allows for greater accuracy, allowing the machine learning algorithm to correctly classify these parameters related to possible attacks.

Habitability and Biosignature Formation in Simulated Martian Aqueous Environments.

Water present on early Mars is often assumed to have been habitable. In this study, experiments were performed to investigate the habitability of well-defined putative martian fluids and to identify the accompanying potential formation of biosignatures. Simulated martian environments were developed by combining martian fluid and regolith simulants based on the chemistry of the Rocknest sand shadow at Gale Crater. The simulated chemical environment was inoculated with terrestrial anoxic sediment from the Pyefleet mudflats (United Kingdom). These enrichments were cultured for 28 days and subsequently subcultured seven times to ensure that the microbial community was solely grown on the defined, simulated chemistry. The impact of the simulated chemistries on the microbial community was assessed by cell counts and sequencing of 16S rRNA gene profiles. Associated changes to the fluid and precipitate chemistries were established by using ICP-OES, IC, FTIR, and NIR. The fluids were confirmed as habitable, with the enriched microbial community showing a reduction in abundance and diversity over multiple subcultures relating to the selection of specific metabolic groups. The final community comprised sulfate-reducing, acetogenic, and other anaerobic and fermentative bacteria. Geochemical characterization and modeling of the simulant and fluid chemistries identified clear differences between the biotic and abiotic experiments. These differences included the elimination of sulfur owing to the presence of sulfate-reducing bacteria and more general changes in pH associated with actively respiring cells that impacted the mineral assemblages formed. This study confirmed that a system simulating the fluid chemistry of Gale Crater could support a microbial community and that variation in chemistries under biotic and abiotic conditions can be used to inform future life-detection missions.

Meteorological factors and incidence of COVID-19 during the first wave of the pandemic in Catalonia (Spain): A multi-county study.

The transmission of coronaviruses can be affected by several factors, including the climate. Due to the rapid spread of COVID-19 and the urgent need for rapid responses to contain the pandemic, it is essential to understand the role that weather conditions on the transmission of SARS-CoV-2. We evaluate the influence of meteorological factors on the incidence of COVID-19 during the first wave of the epidemic in Catalonia. We conducted a geographical analysis at the county level to evaluate the association between mean temperature, absolute humidity, solar radiation, and the cumulative incidence of COVID-19. Next, we used a time-series design to assess the short-term effects of meteorological factors on the daily incidence of COVID-19. We found a geographical association between meteorological factors and the cumulative incidence of COVID-19, from the end of March to June 2020, and a lesser extent in the short-term on the daily incidence during the first wave of the epidemic in Spain. Our findings suggest that warm and wet climates may reduce the incidence of COVID-19 in Catalonia. However, policy makers must interpret with caution any COVID-19 risk predictions based on climate information alone.

Active microbial ecosystem in glacier basal ice fuelled by iron and silicate comminution-derived hydrogen.

The basal zone of glaciers is characterized by physicochemical properties that are distinct from firnified ice due to strong interactions with underlying substrate and bedrock. Basal ice (BI) ecology and the roles that the microbiota play in biogeochemical cycling, weathering, and proglacial soil formation remain poorly described. We report on basal ice geochemistry, bacterial diversity (16S rRNA gene phylogeny), and inferred ecological roles at three temperate Icelandic glaciers. We sampled three physically distinct basal ice facies (stratified, dispersed, and debris bands) and found facies dependent on biological similarities and differences; basal ice character is therefore an important sampling consideration in future studies. Based on a high abundance of silicates and Fe-containing minerals and, compared to earlier BI literature, total C was detected that could sustain the basal ice ecosystem. It was hypothesized that C-fixing chemolithotrophic bacteria, especially Fe-oxidisers and hydrogenotrophs, mutualistically support associated heterotrophic communities. Basal ice-derived rRNA gene sequences corresponding to genera known to harbor hydrogenotrophic methanogens suggest that silicate comminution-derived hydrogen can also be utilized for methanogenesis. PICRUSt-predicted metabolism suggests that methane metabolism and C-fixation pathways could be highly relevant in BI, indicating the importance of these metabolic routes. The nutrients and microbial communities release from melting basal ice may play an important role in promoting pioneering communities establishment and soil development in deglaciating forelands.

Avaliação de rugosidade de superfície de dentes clareados com e sem ativação a laser / Assessment of the roughness oh the surface enamel of teeth bleached with and without activated by laser

Introdução: O tratamento de clareamento é muito usado hoje em dia. O dentista precisa saber como aplicar e indicar uma técnica segura para o tratamento. Objetivo: O propósito deste estudo é medir a rugosidade de superfície do esmalte dentário, submetido a clareamento com e sem ativação por aparelho de LASER (Light Amplification Stimulated Emission of Radiation). Pare estabelecer parâmetros aos clínico para uma utilização segura da técnica clareadora a ser empregada. Material e métodos: Foram coletados 27 dentes anteriores bovinos e armazenados em timol a 1% nos primeiros 7 dias. 3 grupos (9 dentes por grupo) foram criados.O grupo controle (C) não foi submetido a qualquer tratamento clareador e foi armazenado em timol 1. O primeiro grupo teste foi submetido ao uso de um gel clareador peróxido de hidrogênio a 37% em 3 aplicações de 15 minutos . (G). O 3° grupo foi submetido ao mesmo agente clareador e foi ativado por LASER, sendo feitas 3 aplicações de 9 minutos ( intermitentes), durante 3 sessões . Entre cada sessão de clareamento, os dentes foram mantidos em soro Após a submissão dos grupos ao tratamento clareador, todos os espécimes foram submetidos à avaliação de rugosidade superficial no aparelho rugosímetro Mitutoyo SJ. 201®, aferindo-se a rugosidade do esmalte incisal, no sentido mesio-distal. Resultados: Foi observada a diferença estatística significativa entre os grupos controle e gel. Já o grupo gel + laser foi considerado estatisticamente semelhante ao grupo controle. Conclusão: Encontrou-se diferença estatística significativa na rugosidade superficial entre os grupos tratados com gel e o grupo controle, o Os grupos tratados com gel+ laser e grupo controle apresentaram semelhança estatística em relação à modificação superficial do esmalte porém ambos são diferentes do grupo tratado com gel. Os resultados sugerem que, o fator tempo de aplicação, pode ter influenciado de maneira importante.

Introduction: The bleaching is a treatement used a lot in nowdays. The dentist must know how apply and means a safe bleaching technique. Objective: The aim of this study was to measure the surface roughness of dental enamel, exposed to bleaching procedures with and without the use of a LASER. The research intents to give clinicians parameters for a safe bleaching technique. Material and methods: 27 anterior bovine teeth stored in thimol 1 % in the initial 7 days post extraction. The samples were separated into 3 groups of 9 each. The control group G did not receive bleaching procedures and was kept in thimol 1 %. The second group went through bleaching procedures with hydrogen peroxide 37% , 3 applications of 15 minutes each. Third group received the same bleaching formula but differed receiving a LASER instead of a halogen light and a different time lapse for each application of 9 minutes each during 3 sessions. Between each bleaching session, the teeth were kept in sodium chloride. After the tests were complete all specimenswere submitted to roughness evaluation in the mitutoyo SJ. 201®, checking the roughness of incisal enamel in the m -distal aspect. Results: significant statistical difference was found between groups control and gel. Group Gel + Laser was considered statistically similar to the control group. Conclusion: Statistical difference was found in the roughness surface between groups treated with gel + laser and the control group presented statistical resemblance in relation to its enamel surface modification but they?re different than the group treated with gel. Results suggests that time factor of application, might have influenced the study.

Malária grave / Severe malaria

A malária, conhecida também como paludismo é uma doenca infecciosa do tipo febril, causada por protozoários do gênero Plasmodium, transmitida pela picada de um mosquito do gênero Anopheles. Ocorre, sobretudo, em áreas tropicais da África, da Ásia, da Amética Latina e do Pacífico sul-ocidental. A doença se apresenta de diversas formas, inclusive quadros graves, podendo se transformar em urgência, com complicações e óbito. Os autores apresentam o caso de um paciente que deu entrada em seu serviço com quadro de febre alta, calafrios e história de viagem recente a área endêmica de malália. Houve dificuldade no diagnóstico, devido à epidemia de outras doenças infecciosas e febris em nosso meio, como o dengue. Foi feito o diagnóstico de malária e, apesar da introdução da mediciação específica, o paciente evoluiu rapidamente para síndrome da resposta inflamatória sistêmica e choque, não sendo possível revertê-la, culminando com óbito