Toxidade de microplásticos em plantas : uma revisão crítica e boas práticas para experimentação

As facilidades advindas do uso de produtos plásticos têm um alto custo ambiental: os elevados níveis de poluição devido à degradação e fragmentação dos polímeros sintéticos, resultando em pequenas partículas denominadas microplásticos (MP, > 5 μm). As consequências da crescente contaminação ambiental por estas partículas estão entre os grandes desafios que a humanidade terá que enfrentar nas próximas décadas. Uma vez disponíveis no ambiente, estas partículas podem interagir com o solo e alterar sua a estrutura físico-química, afetando negativamente a biota local. Ambientes agrícolas são especialmente afetados devido às práticas utilizadas atualmente, como o uso de fertilizantes à base de lama sedimentada durante o tratamento de água e o uso de coberturas plásticas. As pesquisas com MP e plantas terrestres ainda são incipientes, iniciando apenas em 2018, e assim os métodos de estudo ainda estão em desenvolvimento, o que dificulta a padronização dos experimentos. A presença de MP no ambiente pode afetar a produtividade das espécies vegetais, causando alterações metabólicas, citológicas e genéticas, diminuindo o tamanho e número de sementes, sendo absorvidas e transferidas para os diferentes órgãos. O objetivo desta dissertação foi apresentar o estado da arte de experimentos com plantas terrestres e MP, elencando potenciais efeitos destas partículas nas plantas e em sistemas agrícolas e apresentando uma análise cienciométrica das publicações da área. Dada a problemática encontrada na não padronização dos experimentos, e as lacunas de informações nas metodologias e publicações disponíveis, este trabalho também objetivou apresentar uma sessão com boas práticas necessárias para a montagem e condução de experimentos com MP, trazendo uma visão crítica formada a partir das leituras e observações, além de um estudo de caso abordando um experimento realizado por nosso grupo de pesquisa. A contaminação por MP pode acarretar a danos severos às colheitas e à saúde alimentar de seres humanos, porém, mais estudos na área precisam ser desenvolvidos para melhor avaliar o potencial tóxico destas partículas sobre a o crescimento, desenvolvimento e nutrição das plantas, além de efeitos ecológicos e agronômicos em larga escala.The facilities arising from the use of plastic products have a high environmental cost: the high levels of pollution due to the degradation and fragmentation of synthetic polymers, resulting in small particles, called microplastics (MP, > 5 μm). The consequences of the increasing environmental contamination by these particles are among the great challenges that humanity will face in the coming decades. Once available in the environment, these particles can interact with soil and change its physical-chemical structure, negatively affecting the local biota. Agricultural environments are especially affected due to the practices currently used, such as the use of sedimented mud-based fertilizers during water treatment and the use of plastic covers. Research with MP and land plants is still incipient, starting only in 2018, thus the study methods are still under development, which makes it difficult the standardization of the experiments. The presence of MP in the environment can affect the productivity of plant species, causing metabolic, cytological and genetic changes, reducing the size and number of seeds, being absorbed and transferred to the different organs. The objective of this dissertation was to present the state of the art of experiments with terrestrial plants and MP, listing potential effects of these particles on plants and agricultural systems and presenting a scientometric analysis of publications in the area. Given the problems found in the non-standardization of experiments, and the information gaps in the methodologies and publications available, this work also aimed to present a session with good practices necessary for the setting up and conducting of experiments with MP, bringing a critical view formed from the readings and observations, in addition to a case study addressing an experiment carried out by our research group. MP contamination can cause severe damage to crops and human food health, however, more studies need to be developed to better evaluate the toxic potential of these particles on growth, development and nutrition of plants, in addition to effects on ecological and agronomic systems on a large scale

A Lightweight Regression Method to Infer Psycholinguistic Properties for Brazilian Portuguese

Psycholinguistic properties of words have been used in various approaches to Natural Language Processing tasks, such as text simplification and readability assessment. Most of these properties are subjective, involving costly and time-consuming surveys to be gathered. Recent approaches use the limited datasets of psycholinguistic properties to extend them automatically to large lexicons. However, some of the resources used by such approaches are not available to most languages. This study presents a method to infer psycholinguistic properties for Brazilian Portuguese (BP) using regressors built with a light set of features usually available for less resourced languages: word length, frequency lists, lexical databases composed of school dictionaries and word embedding models. The correlations between the properties inferred are close to those obtained by related works. The resulting resource contains 26,874 words in BP annotated with concreteness, age of acquisition, imageability and subjective frequency.Comment: Paper accepted for TSD201

Aspectos florísticos, fitossociológicos e da biologia da conservação do componente arbóreo de um fragmento de mata de restinga arenosa, Cidreira, RS

A vegetação nativa do país vem sendo dizimada devido ao uso irresponsável dos recursos e ocupação antrópica sem limites, cedendo lugar para grandes empreendimentos, monoculturas e pastoreio, causando danos irreversíveis não só no local degradado, mas no ecossistema todo. A planície costeira do estado não é diferente, a urbanização tem levado a graves problemas ambientais, no Litoral Norte os locais com vegetação original são cada vez mais raros. As restingas se distribuem ao longo da costa brasileira, sendo determinadas por depósitos arenosos que sofrem com a influência marinha. Com o intuito de caracterizar um remanescente florestal de restinga arenosa, foi realizado um levantamento florístico e fitossociológico (em uma porção de um capão de aproximadamente 15 ha), na margem sudoeste da Lagoa da Fortaleza (30º8’38”S. 50º14’47”O.), no município de Cidreira, Rio Grande do Sul. O levantamento fitossociológico foi realizado seguindo o método das parcelas, sendo realizadas 50 amostras de 10m × 10m, em vários pontos, totalizando 0,5 ha, amostrando-se todos indivíduos arbóreos com DAP ≥ 5cm. Para o levantamento florístico foi utilizado o método do caminhamento, abrangendo toda área do remanescente florestal. O levantamento fitossociológico resultou em 1352 ind./ha em 34 espécies, divididas entre 24 famílias. O gráfico do agrupamento das classes de diâmetro do caule (DAP) apresentou o padrão de “J” invertido, ilustrando que a estrutura mantém um padrão supostamente de regeneração da mata, Entretanto, é recomendável que sejam feitos estudos com o componente regenerante (DAP < 5 cm) para confirmar isso ou não. O índice de Shannon resultou em H’=2,43 e o de equabilidade de Pielou foi de J’=0,69. De acordo com a Área Basal elevada para este remanescente florestal (36,98 m²/ha) e pela presença de muitas espécies de estágios sucessionais tardios (escassa presença de pioneiras) este remanescente pode ser classificado como primário, mesmo que já tenha sofrido impactos, porém muito provavelmente não teve corte raso e mantém sua estrutura básica arbórea sem indícios de alteração. Duas espécies arbóreas ameaçadas que constam no Decreto Estadual Nº 52.109/2014, foram encontradas nas unidades amostrais: Ocotea catharinensis e Annona maritima. Quanto ao levantamento florístico, foram encontradas 51 espécies em 27 famílias. As características observadas no capão seguem o esperado para as matas de restinga. Foi observada a circulação de gado no interior da mata, o que deve influenciar diretamente o componente regenerante. Mais estudos devem ser realizados para uma caracterização mais fiel do remanescente florestal, porém o trabalho realizado foi importante para alertar sobre a problemática da fragmentação dos ambientes no litoral, e quanto à importância desses remanescentes para abrigo da flora nativa, algumas espécies com interesse social, outras ameaçadas de extinção, e para a fauna.Our country’s native vegetation has been devastated mainly due to irresponsible use of natural resources and widespread anthropic occupation, giving way to major developments, monoculture agriculture and grazing, leading to irreversible damage not only on degraded sites but in the ecosystem as a whole. The coastal plain of Rio Grande do Sul is not different: urbanization has led to severe environmental issues. On its northern coast, for example, places where the original vegetation remains are increasingly rare. Restinga vegetation is distributed along the Brazilian’s coast, and is characterized by sand deposits under marine influence. With the purpose of outlining a remnant vegetation, a floristic and phytosociological survey of approximately 15 ha at the sandbank vegetation of the southwest shore of Lagoa da Fortaleza (30º8’38”S. 50º14’47”W), Cidreira, Rio Grande do Sul, was carried out. The physociological survey was performed following the quadrats sampling method, where fifty 10x10 m random quadrats were applied at the site, amounting to 0,5 ha. All arboreal individuals with trunk diameter at breast height (DBH) bigger than 5 cm were evaluated. The walkover method was applied for the floristic survey, where the arboreal taxa were assessed, covering the whole sandbank vegetation area. The phytosociological survey reported 1352 ind./ha of 34 species, distributed into 24 families. The DBH grouping graph presented an “inverted-J” pattern, alluding that the vegetation might be regenerating; however, further studies on regenerating patterns (DBH <5cm) are recommended to be carried out on the site. The Shannon’s diversity index returned a value of H’=2,43 whilst the Pielou’s equitability index returned J’=0,69. The remnant’s high values of basal area (36,98 m²/ha) associated to the notable presence of late successional stage species (and a small amount of pioneers) suggest a region of primary succession, with some impact degree being observed but presenting a consistent arboreal structure with no signs of anthropic modification. Two different threatened arboreal species, listed at the law decree Nº 52.109/2014, were found at the sampling units: Ocotea catharinensis e Annona marítima. Regarding the floristic survey, 51 species distributed into 27 families were registered. The characteristics observed at the site follow the expected for sandbank vegetation. It was also detected some grazing activity into the woods, directly affecting the regenerating component. Further research must be done for a more reliable characterization of the area; however, this study played a significant role on addressing the coastal habitat fragmentation issue, and demonstrating, also, how important those vegetation remnants are for native vegetation sheltering, in which are included some social relevant species, some of them present into the state’s list of threatened species

Automatic Non-functional Testing of Code Generators Families

International audienceThe intensive use of generative programming techniques provides an elegant engineering solution to deal with the heterogeneity of platforms and technological stacks. The use of domain-specific languages for example, leads to the creation of numerous code generators that automatically translate highlevel system specifications into multi-target executable code. Producing correct and efficient code generator is complex and error-prone. Although software designers provide generally high-level test suites to verify the functional outcome of generated code, it remains challenging and tedious to verify the behavior of produced code in terms of non-functional properties. This paper describes a practical approach based on a runtime monitoring infrastructure to automatically check the potential inefficient code generators. This infrastructure, based on system containers as execution platforms, allows code-generator developers to evaluate the generated code performance. We evaluate our approach by analyzing the performance of Haxe, a popular high-level programming language that involves a set of cross-platform code generators. Experimental results show that our approach is able to detect some performance inconsistencies that reveal real issues in Haxe code generators

Cats shedding pathogenic Leptospira spp.-An underestimated zoonotic risk?

Shedding of DNA of pathogenic Leptospira spp. has been documented in naturally infected cats in several countries, but urinary shedding of infectious Leptospira spp. has only recently been proven. The climate in Southern Chile is temperate rainy with high annual precipitations which represents ideal preconditions for survival of Leptospira spp., especially during spring and summer. The aims of this study were to investigate shedding of pathogenic Leptospira spp. in outdoor cats in Southern Chile, to perform molecular characterization of isolates growing in culture, and to assess potential risk factors associated with shedding. Urine samples of 231 outdoor cats from rural and urban areas in southern Chile were collected. Urine samples were investigated for pathogenic Leptospira spp. by 4 techniques: qPCR targeting the lipL32 gene, immunomagnetic separation (IMS)-coupled qPCR (IMS-qPCR), direct culture and IMS-coupled culture. Positive urine cultures were additionally confirmed by PCR. Multilocus sequence typing (MLST) was used to molecularly characterize isolates obtained from positive cultures. Overall, 36 urine samples (15.6%, 95% confidence interval (CI) 11.4-20.9) showed positive results. Eighteen (7.8%, 95% CI 4.9-12.1), 30 (13%, 95% CI 9.2-18), 3 (1.3%, 0.3-3.9) and 4 cats (1.7%;95% CI 0.5-4.5) were positive in qPCR, IMS-qPCR, conventional culture, and IMS-coupled culture, respectively. MLST results of 7 culture-positive cats revealed sequences that could be assigned to sequence type 17 (6 cats) and sequence type 27 (1 cat) corresponding to L. interrogans (Pathogenic Leptospira Subgroup 1). Shedding of pathogenic Leptospira spp. by cats might be an underestimated source of infection for other species including humans. The present study is the first one reporting growth of leptospires from feline urine in culture in naturally infected cats in South-America and characterisation of culture-derived isolates. So far, very few cases of successful attempts to culture leptospires from naturally infected cats are described worldwide

Prevalência de fatores associados à autopercepção do comportamento sexual de risco em adultos e idosos

Introduction: sexual risky behaviour can be defined as that which exposes the individual to the greatest probability of contracting a sexually transmitted infection. Objective: To evaluate the self-perception of sexual risky behaviour and associated factors. Methods: a cross-sectional study was conducted with 1.443 adults and seniors, of both sex, users of Primary Health Care in Passo Fundo – RS, from whom sociodemographic and behaviour characteristics were analysed. Results: The prevalence of self-perceived sexual risky behaviour was 15% (IC95 13-17). In the sample, 8,8% reported having had 2 or more sexual partners in the last year, while 64,6% did not use condoms during sexual intercourse. Higher probability of self-perceived sexual risky behaviour was identified in individual’s whit basic education, in those without a spouse and who reported a multiplicity of sexual partners. Conclusion: Despite the considerable prevalence of self-perception of risky sexual behavior, it was not related to not use of condoms, reinforcing the need for constant sexual education of the adult and elderly population who use primary care, aiming at reducing exposure to sexually transmitted diseases.Introdução: o comportamento sexual de risco pode ser definido como aquele que expõe o indivíduo à maior probabilidade de contrair uma infecção sexualmente transmissível. Objetivo: avaliar a autopercepção do comportamento sexual de risco e seus fatores associados. Metodologia: foi realizado um estudo transversal com 1.443 adultos e idosos, de ambos os sexos, usuários da Atenção Primária à Saúde (APS) de Passo Fundo – RS, dos quais foram analisadas características sociodemográficas e comportamentais. Resultados: a prevalência da autopercepção do comportamento sexual de risco foi de 15% (IC95 13-17). Da amostra, 8,8% relataram ter tido dois ou mais parceiros sexuais no último ano, enquanto 64,6% não fazem uso de preservativo durante a relação sexual. Maior probabilidade de autopercepção do comportamento sexual de risco foi identificado em indivíduos cuja escolaridade é de nível fundamental, sem cônjuge e que relataram multiplicidade de parceiros sexuais. Conclusão: apesar da considerável prevalência da autopercepção de comportamento sexual de risco, esta não esteve relacionada ao não uso do preservativo, reforçando a necessidade de constante educação sexual da população adulta e idosa usuária da APS, visando à redução da exposição às doenças sexualmente transmissíveis

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO