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1.
Diagn. tratamento ; 29(2): 81-5, abr-jun. 2024.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1553900

RESUMO

Contexto: Luteoma é neoplasia rara e benigna do ovário, específica da gravidez. Considera-se que seja causada por efeitos hormonais, principalmente da gonadotrofina coriônica. Objetivo: Analisar artigos selecionados sobre luteoma da gravidez e realizar revisão bibliográfica a partir dessas publicações. Desenho: A busca dos artigos foi realizada por meio da plataforma PubMed. Procedeu-se uma busca aos descritores da doença e seu correspondente em inglês (luteoma) no portal da BVSalud. Métodos: Consistiu em revisão bibliográfica, onde foram utilizados artigos publicados de 1972 até 2022. Resultados: A origem celular dos luteomas ainda é desconhecida, mas considera-se que tal processo ocorra devido a uma reação hiperplásica à gravidez, visto que o efeito de virilização regride após o parto. Discussão: Sendo pouco diagnosticado, tendo menos de 200 casos reportados, são geralmente achados durante parto cesáreo ou durante ligadura tubária no pós-parto. Seu aparecimento está relacionado a fatores hormonais da gravidez e hiperplasia ocasionada pela luteinização das células estromais. Os efeitos do luteoma gravídico no organismo estão relacionados, além da virilização da paciente e do feto, com o surgimento da síndrome do ovário policístico e diabetes. Conclusões: Tendo baixa incidência, o luteoma gravídico pode se apresentar como desafio para seu diagnóstico adequado. O diagnóstico precoce permitirá o tratamento adequado, evitando-se efeitos indesejáveis, virilizantes, para a gestante e para o nascituro. É fundamental o preparo dos profissionais de saúde para o diagnóstico e tratamento do luteoma gravídico.

2.
Neotrop Entomol ; 53(3): 541-551, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358647

RESUMO

Co-occurrence a correlation profiles are driven by different factors (exogenous and endogenous) and drawing a profile of association between species based on co-occurrence, without assessing how these species vary in terms of ecological niche can lead to wrong conclusions. The objective was to determine the co-occurrence and correlation patterns of phytophagous insects in canola crop and to evaluate how these patterns varied according to the crop stage (phenology-biotic) and sowing times (agricultural practice-abiotic). We found that the patterns of co-occurrence and correlation between species were reflections of population variations due to the phenology and sowing times of canola. Variations in the multi-species abundance matrix were influenced by mean air temperature and accumulated rainfall. The main species associated with canola in southern Brazil, in terms of abundance, were P. xylostella, D. speciosa, and N. viridula. These species were mostly negatively associated. When evaluating their population variations, we found that they explore different temporal niches, whether in terms of phenology or sowing times. Finally, we demonstrate empirically that despite being important, association patterns based on co-occurrence and correlation should be interpreted in light of the understanding of patterns of niche exploitation and temporal variation of species.


Assuntos
Brassica napus , Animais , Brasil , Estações do Ano , Produtos Agrícolas , Insetos , Temperatura
3.
Sci Total Environ ; 912: 168937, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38029983

RESUMO

The geochemical processes involved in the Amazon soils formation are not totally understood because its geological and pedological features were formed during different geological events and different times. The Southwestern region of Amazonas State is an example of a region where the soils were developed from rocks formed by sedimentary processes and, nowadays, the soils continue receiving seasonal inputs from the Andes sediments. Data on geochemical patterns of this region are scarce, and there is no information about the possible effects of the natural or unnatural enrichment of potentially toxic elements (PTEs). Thus, this study represents the first research into the geochemical patterns of PTEs in soils of Southwestern Amazonas State. Further, we carried out a human health risk assessment and a proposal for Quality Reference Values (QRV) for thirteen PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Ti, V, Zn and Zr). Our findings showed that the PTEs contents in soil samples collected in the lowland areas are strongly influenced by sediments inputs, while samples localized in the highland areas are weakly influenced by sediments inputs and present depletion of PTEs. Barium, Cr, Cu, Ni and Pb were the PTEs most influenced by sediment's deposition. The soil contamination assessment showed the existence of enrichment of the potentially toxic elements in soil samples, which may be a consequence of the natural inputs of the Andean sediments. Furthermore, Co and Cr exceed the safety zone for carcinogenic risk assessment, which indicates the need to monitor these elements and their possible effects on the health of the population in this region.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Solo/química , Metais Pesados/análise , Monitoramento Ambiental , Brasil , Valores de Referência , Chumbo , Poluentes do Solo/análise , Medição de Risco
4.
J Funct Biomater ; 14(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37998111

RESUMO

Adequate root canal sealing is essential for the success of endodontic treatment. There are numerous techniques available; identifying simple and efficient techniques is important to provide good patient care. The purpose of the study was to compare the maximum penetration depth and the percentage of sealant penetration of an endodontic sealer into dentine tubules using cold lateral condensation, continuous wave, and hybrid techniques, and to contrast the effectiveness of two different tapered gutta-percha master cones (0.02 and 0.04). A sample of sixty single root teeth was used. Six experimental groups were formed from the three filling techniques and the two tapered master cones. Images were acquired using a confocal laser scanning microscope. In the apical root third, the penetration percentage was higher in the hybrid compared with the continuous wave technique. The results indicated a higher penetration depth of hybrid compared with cold lateral condensation in the middle and coronal thirds, and in the apical third, a higher penetration was identified in the hybrid group compared with the continuous wave group. No significant differences in penetration were found comparing 0.02 with 0.04 taper gutta-percha groups. The coronal cross-sections presented a higher penetration than the apical third sections. In conclusion, the hybrid technique a had higher maximum sealer penetration than the continuous wave in the apical third, and the coronal third hybrid and continuous wave had a higher penetration than cold lateral condensation.

5.
J Hazard Mater ; 449: 131034, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-36827724

RESUMO

Physical and chemical remediation techniques used in contaminated areas are expensive and damaging to the soil structure. Biological alternatives, such as phytoremediation, are economical and applicable to large areas. The main limitation of phytoremediation is identifying plants that are both capable of stabilizing and/or absorbing metals from soil and adapted to edaphoclimatic conditions of the contaminated areas. The objective of this study is to evaluate the ability of plant species adapted to Brazilian semi-arid conditions to grow in soils contaminated with Pb. A greenhouse experiment was carried out in a 4 × 5 factorial: four plant species (M. oleifera, P. juliflora, A. peregrina, and U. ruziziensis) and five Pb concentrations in soil (0.0; 0.52; 1.05; 2.10, and 4.20 g kg-1). All species grew at all Pb levels, but only P. juliflora and A. peregrina did not exhibit significant reductions in most growth variables. U. ruziziensis, despite showing reductions in growth variables, was the species with the highest dry matter accumulation in both shoots and roots, in addition to accumulating higher amounts of Pb. We conclude that the species P. juliflora, A. peregrina and U. ruziziensis are more suitable for cultivation in soils containing high levels of Pb.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Chumbo/análise , Poluentes do Solo/análise , Plantas , Solo/química , Raízes de Plantas/química , Metais Pesados/análise
6.
Polymers (Basel) ; 15(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679277

RESUMO

The purpose of this study was to evaluate the color changes of feldspathic ceramics CEREC Blocs (Dentsply Sirona, Milford, DE, USA) when cemented with different luting agents, while varying the ceramic thickness. Seventy ceramic discs of feldspathic ceramic (A2 shade) were obtained with 0.5 and 0.8 mm thicknesses. Seventy composite discs (A3 shade) 1 mm in thickness were used as substrates. After being polished and conditioned, the ceramic and composite discs were cemented with different resin cements and a flowable composite: Variolink® Esthetic Light, Neutral and Warm (Ivoclar Vivadent, Schaan, Liechtenstein); RelyXTM Veneer B0.5, Translucent and A3 Opaque/yellow shades (3M Oral Care, St. Paul, MN, USA); G-aenial® Universal Flow A2 (GC Europe, Leuven, Belgium). Color difference (ΔE) was determined using a spectrophotometer. A two-way ANOVA and multiple comparisons were performed using the Bonferroni method with a 95% confidence interval. Variolink® Neutral showed the highest ΔE (15.12 ± 0.71) and RelyXTM Veneer A3 the lowest value (1.59 ± 0.33). There are no statistically significant differences between the two ceramic thicknesses for Variolink® Light (p = 0.230) and RelyXTM Veneer B0.5 (p = 0.318) cements. The feldspathic ceramic final color is influenced by the cement used and the ceramic thickness. The use of different cements in a thin ceramic has a clinically significant impact on the final esthetic result.

7.
Sci Educ (Dordr) ; : 1-23, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36039352

RESUMO

Understanding how and why science works is a major goal of science education. The aim of this article is to analyze the influence of a research experience in real science contexts, in the thinking and practice of preservice elementary teachers regarding inquiry and nature of science teaching. An in-depth case study which highlights the affordances and shortcomings of the participants' immersion in real science contexts and in seminars and its impact on participants' thoughts and practices of nature of science and inquiry will be presented. Interviews, observations, diaries, and videotaped seminars were used for data collection. Our findings suggest that the research experience, as well as moments of reflection, contributed to enhance the relevance of an inquiry-based teaching and teaching about NOS in the participants' discourse. However, the implementation of these classroom practices was limited and seemingly prevented due to various constraints, namely the initial teacher training, participants' lack of teaching experience, and those associated with elementary students and the curriculum.

8.
J Funct Biomater ; 13(3)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35997458

RESUMO

When implants are required in prosthodontics treatment, one of the most important decisions is the choice of the final crown and the type of connection to the implant through the abutment. Hybrid abutments are becoming a primary choice. They are projected and produced with materials whose properties guarantee the required mechanical features (including resistance) and take advantage of the hybrid abutment crown retention between screw and cement. However, a review of the mechanical resistance of the different abutment types and associated materials is still lacking. This review aimed to study the in vitro mechanical efficiency of the hybrid abutments used in oral rehabilitation. METHODS: A systematic review was conducted using the PubMed, B-on, and Google Scholar databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: 75 articles were identified from all databases, and 33 were selected after abstract screening. Thus, 21 studies were included in the review after full-text reading. Among the materials used for crowns, lithium disilicate was, aesthetically, the primary choice for its aesthetic and moderate strength. On the other hand, zirconia showed the best fracture resistance. Regarding the different kinds of abutments, there is still some lack of knowledge about the best design. CONCLUSIONS: Within the limitations of this systematic review, we can conclude that hybrid pillars are an excellent choice for oral rehabilitation through implants, showing improved resistance when including materials such as zirconia and lithium disilicate.

9.
Sci Total Environ ; 817: 152972, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35026263

RESUMO

Several anthropic activities, especially mining, have contributed to the exacerbation of contents of potentially toxic elements in soils around the world. Mines can release a large amount of direct sources of contaminants into the environment, and even after the mines are no longer being exploited, the environmental liabilities generated may continue to provide contamination risks. Potentially toxic elements (PTEs), when present in the environment, can enter the food chain, promoting serious risks to human health and the ecosystem. Several methods have been used to determine the contents of PTEs in soils, but most are laborious, costly and generate waste. In this study, we use a methodological framework to optimize the prediction of levels of PTEs in soils. We used a total set of 120 soil samples, collected at a depth of 0-10 cm. The covariate database is composed of variables measured by proximal sensors, physical and chemical soil characteristics, and morphometric data derived from a DEM with a spatial resolution of 30 m. Five machine learning algorithms were tested: Random Forests, Cubist, Linear Model, Support Vector Machine and K Nearest Neighbor. In general, the Cubist algorithm produced better results in predicting the contents of Pb, Zn, Ba and Fe compared to the other tested models. For the Al contents, the Support Vector Machine produced the best prediction. For the Cr contents, all models showed low predictive power. The most important covariates in predicting the contents of PTEs varied according to the studied element. However, x-ray fluorescence measurements, textural and morphometric variables stood out for all elements. The methodology structure reported in this study represents an alternative for fast, low-cost prediction of PTEs in soils, in addition to being efficient and economical for monitoring potentially contaminated areas and obtaining quality reference values for soils.


Assuntos
Metais Pesados , Poluentes do Solo , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Metais Pesados/análise , Medição de Risco/métodos , Solo/química , Poluentes do Solo/análise
10.
Clin Exp Dent Res ; 8(1): 257-261, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35001545

RESUMO

OBJECTIVE: The purpose of this study is to evaluate the color changes of lithium disilicate ceramics when cemented with different brands of cement by varying the thickness of the ceramic. MATERIALS AND METHODS: Forty ceramic discs, shade A2, were fabricated with 0.5 and 0.8 mm thickness. Forty composite resin discs, shade A3, were also produced. The ceramic samples were cemented to the composite resin discs, with two colors of resin cement, Neutral and Warm. A spectrophotometer evaluation was made. Translucency and color change analysis was performed by calculating the ΔE. A two-way analysis of variance test and multiple comparisons were performed using the Bonferroni method with a 95% confidence interval. RESULTS: There are statistically significant differences between the two ceramic thicknesses with different brands of cement (p < .001). In addition, using the translucency analysis it was found that there are statistically significant differences between the two ceramic thicknesses in both types of cement (p < .001). CONCLUSIONS: The use of different cementation materials on lithium disilicate ceramics appears to have little visible influence at the clinical level. Different ceramic thicknesses have a clinically visible influence on the final restoration color.


Assuntos
Cerâmica , Cimentos de Resina , Cor , Resinas Compostas , Cimentos Dentários
11.
Sci Total Environ ; 806(Pt 2): 151191, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710416

RESUMO

Rare earth elements (REEs) are a grouping of elements that encompasses lanthanides, yttrium and scandium due to their similar chemical properties and occurrence in ore deposits. Over the past few decades, economic interest in REEs has increased due to their use in several types of industries such as high-tech, medicine and agriculture. Extraction of REEs has been followed, in general, by incorrect disposal of tailing and waste, creating hazardous conditions in several countries. However, the magnitude of the possible impacts on ecosystem and human health are relatively unknown, especially in tropical systems. Thus, the objectives of this study were to assess the geochemical mobility and the bioaccessibility of REEs based on a series of chemical extractions and in vitro essay. We also tested two promising simple protocols (0.01 mol L-1 CaCl2 and 0.43 mol L-1 HNO3) for measuring REE bioaccessible fractions through a single extraction. Our findings show that the bioavailable fractions represent less than 20% of the ΣREEs fraction in all soil samples examine. Similarly, the oral bioaccessibility obtained by two in vitro methods (Gastric protocol and Gastric-Intestinal protocol) and by the single extraction tests represented less than 20% of the ΣREE contents. The non-carcinogenic risks and the carcinogenic risks associated to REEs oral exposure were low for children and adults. The extractions with 0.01 mol L-1 CaCl2 showed great potential as a method for measuring the REEs bioaccessible fraction.


Assuntos
Metais Terras Raras , Poluentes do Solo , Criança , Ecossistema , Humanos , Metais Terras Raras/análise , Medição de Risco , Solo , Poluentes do Solo/análise
12.
Environ Pollut ; 277: 116743, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33640811

RESUMO

Rare earth elements (REEs) are generally defined as a homogenous group of elements with similar physical-chemical properties, encompassing Y and Sc and the lanthanides elements series. Natural REEs contents in soils depend on the parent material, the soil genesis processes and can be gradually added to the soil by anthropogenic activities. The REEs have been considered emerging pollutants in several countries, so the establishment of regulatory guidelines is necessary to avoid environmental contamination. In Brazil, REE soils data are restricted to some regions, and knowledge about them in the Amazon soils is scarce, although this biome covers more than 40% of the Brazilian territory. Thus, the objectives of this study were to determine the REE content in soils of two hydrographic basins (Solimões and Rio Negro) of the Amazon biome, establish their Quality Reference Values (QRV) and to investigate the existence of enrichment of REEs in urban soils. The ΣREE(Y + Sc) content of Solimões surface samples was 109.28 mg kg-1 and the ΣREE(Y + Sc) content in the subsurface samples was 94.11 mg kg-1. In soils of Rio Negro basin, the ΣREE(Y + Sc) was 43.95 15 mg kg-1 surface samples and 38.40 mg kg-1 in subsurface samples. The ΣREE(Y + Sc) in urban topsoils samples was 38.62 mg kg-1. The REEs contents pattern in three studied areas are influenced in different amplitude by natural soil properties. The REEs content in urban topsoils were slightly higher than the Rio Negro pristine soils, but the ecological risk was low. QRVs recommend for Solimões soils ranged from 0.01 (Lu) to 145.6 mg kg-1 (Ce) and for Rio Negro soils ranged from 0.05 (Lu) to 15.8 mg kg-1 (Ce).


Assuntos
Metais Terras Raras , Poluentes do Solo , Brasil , Monitoramento Ambiental , Poluição Ambiental , Metais Terras Raras/análise , Solo , Poluentes do Solo/análise
13.
Environ Geochem Health ; 43(9): 3407-3427, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33555492

RESUMO

The city of Manaus is the biggest industrial city of the north Brazilian region, and a haphazard urbanization process characterizes it. The continuous urbanization and industrialization processes have increased the levels of trace elements in the urban environment and have posed great threat on human health. It is, then, essential to assess the pollution levels and the potential risks of the trace elements presence in urban soils. Therefore, the purpose of this study was to investigate the status of trace elements soils pollution and their human health risks to the population of Manaus City. Twenty-two soil samples were collected from the surface layer (0-20 cm), and the contents of Ba, Cr, Mn, Zn, Co, Ni, Cu, Cd and Pb were analyzed. Results showed the predominance of kaolinite, gibbsite and goethite as the main minerals of the clay fraction. The trace elements contents were affected by both natural sources and anthropic activities such as industrial operations and vehicular emissions. The soil contamination assessment by Enrichment Factor showed the existence of eight samples classified as considerably contaminated and two samples classified as highly contaminated. Geoaccumulation index also showed the existence of eight samples exhibiting considerable contamination and one sample showing high contamination. The non-carcinogenic health risk was considered low (HI < 1) to both children and adults. However, the carcinogenic risk of Cd and Pb was higher than the safety limits (CRtotal > 1 × 10-6), indicating that the long exposure to contaminated soils increases the probability of children's cancer occurrence.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Adulto , Brasil , Criança , China , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Oligoelementos/análise , Oligoelementos/toxicidade
14.
Braz. arch. biol. technol ; 64: e21180601, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1355810

RESUMO

Abstract Kriging is a method that estimates values in places not sampled from different interpolators, therefore, widely used to predict the spatial distribution of organisms. However, the different interpolators may vary in performance depending on the organism under study or the area evaluated. The aimed study to compare the ordinary kriging and inverse of distance weighted interpolation methods, applied to the spatial distribution of population density of Tibraca limbativentris in irrigated rice. This study was carried out in Santa Maria, RS, Brazil, in two fields with areas of 1.3 ha and 6.2 ha, respectively. Seven evaluations of the population density of T. limbativentris were carried out, corresponding to the period from sowing to maturation. In these areas the adults of T. limbativentris were quantified and the sum used for the statistical and geostatistical analysis. The sample population of T. limbativentris was submitted to different semivariograms, which were selected through cross-validation. The sample population of T. limbativentris was submitted to different semivariograms, selected by means of cross-validation. Once selected, semivariograms were used in both tested interpolation methods. From the results it was concluded that the ordinary kriging interpolation method performed better in all evaluations performed in both areas. Therefore, we recommend its use for estimating the population density and spatial distribution of T. limbativentris in the irrigated rice throughout the crop phenology. Using appropriate interpolation methods, localized management can be used, reducing costs for controlling this pest and increasing the sustainability of the environment.

15.
Sci Total Environ ; 709: 134471, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31884289

RESUMO

Manaus is the Capital City of Amazonas State, Brazil, in the heart of the Amazon rainforest. Its metropolitan area has a huge hydrographic basin where the disorganized urbanization has caused adverse effects in the urban rivers and creeks water quality. Thus, this study was conducted to evaluate the contents of Ba, Cr, Mn, Zn, Ni, Cu, the physicochemical parameters and their respective health risks in water samples from rivers and creeks located in urban areas with different degrees of urbanization in two different seasons. The determination of the physicochemical parameters showed the samples collected in areas with riparian vegetation presented mean values of temperature, pH, total dissolved solids and electrical conductivity lower than samples collected in urban environment. The hotspots of trace elements content were associated to the presence of industrial and domestic effluents as the main pollution source. The Water Quality Index results denoted a low water quality in four sampling sites, one during the rainy season and three others during the dry season. The overall non-carcinogenic health in the urban rivers was considered high in regions with huge population and intense anthropogenic activity. The results showed the potential risk of some of the trace elements on human beings, especially on children. The main element contributor to non-carcinogenic risk was Cr, although Mn and Ni also contributed to non-carcinogenic risk in a few areas, mainly for children during the dry season.


Assuntos
Rios/química , Brasil , Cidades , Monitoramento Ambiental , Metais Pesados , Medição de Risco , Oligoelementos , Poluentes Químicos da Água
16.
Sci Total Environ ; 709: 136151, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31887517

RESUMO

In November 2015, the Fundão Dam collapsed releasing about 35 million m-3 of iron ore tailings into the environment, which covered approximately 15 km2 of floodplain soils. Four years later, there is still great concern and controversy regarding contamination by heavy metals in the affected areas. Thus, the present study sought to evaluate the heavy metal contents and its distribution in tailings and non-affected soils. Tailings samples were collected in the stretch between Bento Rodrigues and the Candonga hydroelectric plant, in addition to a sample inside the Fundão Dam. Non-affected soils and river sediments from the same region were also collected as a control group. The heavy metal contents in the tailings were lower than in non-affected samples from the same area, discarding the hypothesis of contamination by the tailings mud. The non-affected samples presented high levels of As, Ba, Co, Cr, Cu, Ni and Zn, with at least one sample exceeding the quality reference values (QRV's) established for Minas Gerais state, which indicated a scenario of pre-disaster contamination for the Doce River watershed. Most of the elements (As, Cr, Cu, Ni, V and Zn) were extracted in the residual fraction of the BCR sequential extraction, presenting low risk of release in nature. The health risk assessment for As estimated that all the non-affected soils and sediments from Gualaxo do Norte, Carmo and Doce rivers have carcinogenic risk higher than the acceptable value for children. From our results, it is more likely to conclude that the deposited tailings are not a time-bomb for heavy metals contamination in the region.

17.
Arq. Inst. Biol ; 87: e1202018, 2020. ilus, tab
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1121077

RESUMO

The objective was to identify the dispersion of Tibraca limbativentris (Hemiptera: Pentatomidae) in different phenological phases of irrigated rice. The research was carried out in an area of 20.12 ha, subdivided in four fields of 0.25 to 14.1 ha with the irrigated rice culture, grown under the technical recommendations of the culture. In each field, a sampling grid of 30 × 30 m was generated, with each sampling point corresponding to 1·m-2 (200 plants), sampling was through direct counting. The number of adults of T. limbativentris·m-2 was subjected to descriptive and geostatistical analyzes. Tibraca limbativentris presents border dispersion towards the center of the irrigated rice cultivation area. The highest population densities were estimated in the anthesis and elongation phase.(AU)


O objetivo foi identificar a dispersão de Tibraca limbativentris (Hemiptera: Pentatomidae) em diferentes fases fenológicas do arroz irrigado. A pesquisa foi realizada em uma área de 20,12 ha, subdividida em quatro lavouras de 0,25 a 14,1 ha com a cultura de arroz irrigado, cultivadas sob as recomendações técnicas da cultura. Em cada lavoura, foi gerado um grid de amostragem de 30 × 30 m sendo cada ponto amostral correspondente a 1·m-2 (200 plantas), a amostragem realizada foi através de contagem direta. O número de adultos de T. limbativentris·m-2 foi submetido a análises descritivas e geoestatística. Tibraca limbativentris apresenta dispersão das bordaduras para o centro da área de cultivo de arroz irrigado. As maiores densidades populacionais foram estimadas na fase de antese e elongação.(AU)


Assuntos
Oryza , Irrigação Agrícola , Distribuição Animal , Hemípteros , Brasil , Densidade Demográfica
18.
Dent J (Basel) ; 7(3)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374905

RESUMO

Oral rehabilitation success depends upon the accuracy and dimensional stability of the impressions. The purpose of this study is to evaluate the dimensional changes of a first impression type VPS (Vinyl Polysiloxane) (Imprint™ 4 Preliminary Penta™ Super Quick, 3M ESPE™, St Paul, MN, USA). 10 samples were obtained from this silicone with an automatic mixing machine (Pentamix 2, 3M ESPE™, Seefeld, Germany) according to International Organization for Standardization (ISO) 4823:2000 and stored in the IPQ (Portuguese Institute for Quality) for one week. The measurements were performed by laser interferometry, according to the Michelson technique. The dimensional stability was calculated according to the formula specified in ISO (International Organization for Standardization) 4823:2000. A statistical analysis via a one-way repeated measures ANOVA was performed. The material shrinkage was 0.29 ± 0.15% after setting, 0.32 ± 0.21% at 24 h and 0.30 ± 0.23% after 1 week. No significant shrinkage of the silicone under investigation was found over time. This material can be stored for a week without the risk of clinically significant dimensional changes.

19.
J Environ Manage ; 238: 92-101, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30849602

RESUMO

Arsenic (As) is a toxic and carcinogenic element. Therefore, it is necessary to carry out research on As-contaminated water management in order to achieve the World Health Organization (WHO) standard for drinking water (0.010 mg L-1). A Simplex-Centroid mixture design (SCMD) was used to determine the best mineral composition for both maximum adsorption capacity of As(V) (MAC-As) and residual concentration of As(V) (RC-As), using synthetic poorly crystallized aluminum hydroxide (pAlHyd), calcined layered double hydroxide (cLDH), and two-line ferrihydrite (2ℓFh). The analysis of variance results and the predicted values of models showed a good agreement with the experimental data, indicating that SCMD is a reliable method to optimize As removal through determination of the best mineral composition. The ability of pure synthetic minerals to remove As from water was different among those mixtures thereof, which indicate that the mineral components interacted with each other. Results showed that cLDH was the best As adsorbent. However, it showed a RC-As higher than the WHO standard. The pAlHyd and 2ℓFh exhibited smaller MAC-As, but they lowered RC-As to below 0.010 mg L-1, showing no direct relationship between high MAC-As and low RC-As. Therefore, mineral compositions which combine high adsorption capacity with low residual concentration should work better for removing As from drinking water, ensuring it meets the WHO potability standard. Ternary diagrams for MAC-As and RC-As showed that the best combination for maximizing MAC-As and reducing RC-As should be a mixture of 75-90% of cLDH, 10-20% of pAlHyd, and 0-5% of 2ℓFh.


Assuntos
Arsênio , Poluentes Químicos da Água , Purificação da Água , Adsorção , Minerais
20.
Arq. Inst. Biol ; 86: e0332019, 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1045994

RESUMO

Host plants are key factors in the survival of true bugs during unfavorable periods. The objective of this study was to evaluate the composition, diversity and abundance of pentatomid bugs in Saccharum angustifolium (Nees) Trin. (Poales: Poaceae). Plants were evaluated during the soybean and corn off--season for five years. A total of 250 plants were sampled, the true bug population was counted and used for statistical and faunistic analysis. We observed the occurrence of the species: Euschistus heros (F.), Dichelops furcatus (F.), Dichelops melacanthus (Dallas), Edessa meditabunda (F.), and Edessa ruformaginata (De Geer). Among the species, the highest population density was verified for E. meditabunda, E. heros, and D. furcatus. We also observed a direct effect of the clump diameter on the population density of E. heros, D. furcatus, and E. meditabunda. Finally, we conclude that S. angustifolium plants serve as adequate hibernacles for the survival of true bugs of economic importance during the soybean and corn off-season.(AU)


Plantas hospedeiras são fatores fundamentais na sobrevivência de percevejos durante períodos desfavoráveis. O objetivo deste trabalho foi avaliar a composição, diversidade e abundância de espécies de percevejos pentatomídeos ocorrentes em plantas de Saccharum angustifolium (Nees) Trin (Poales: Poaceae). As plantas foram avaliadas durante a entressafra de soja e milho por cinco anos. Foram amostradas 250 plantas, sendo a população de percevejos contabilizada e utilizada para a análise estatística e faunística. Observamos a ocorrência das espécies: Euschistus heros (F.), Dichelops furcatus (F.), Dichelops melacanthus (Dallas), Edessa meditabunda (F.) e Edessa ruformaginata (De Geer). Entre as espécies, foi verificada uma maior densidade populacional para E. meditabunda, E. heros e D. furcatus. Observamos, também, o efeito direto do diâmetro de touceira sobre a densidade populacional de E. heros, D. furcatus e E. meditabunda. Por fim, concluímos que plantas de S. angustifolium servem como hibernáculos adequados para a sobrevivência de percevejos de importância econômica durante a entressafra de soja e milho.(AU)


Assuntos
Produtos Agrícolas , Cimicidae , Saccharum , Glycine max , Brasil , Análise de Regressão , Zea mays , Cimicidae/classificação , Saccharum/anatomia & histologia
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