Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960’s, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.

ABSTRACT Plutella xylostella cause severe damage on cruciferous plants all over the world. Farmers in several regions of Brazil report increasing inefficiency of chemical control, even when using high insecticide concentrations. We evaluate here the susceptibility of brazilian diamondback moth populations to the Premio® (Chlorantraniliprole), Dipel® (Bacillus thuringiensis var. kurstaki) and Lannate® BR (Oxime Methylcarbamate) insecticides, frequently used in Brazil. Susceptibility bioassays with five field-collected and two laboratory diamondback moth populations were conducted with increasing concentrations of insecticides up to ten times above the recommended concentration. Extremely high and region-dependent resistances were found in field populations against Chlorantraniliprole and B. thuringiensis, with Resistance Ratios up to 370.0 times for the Camocim de São Felix population. For Oxime Methylcarbamate, we were not able to do Probit analyses for the field populations because of very low mortality rates. Laboratory populations showed resistance to the three tested insecticides with all LC50 concentrations exceeding the recommended doses by at least 3 times. Our results show strong and variable resistance to the three tested insecticides according to the region of origin. To maintain efficient pest control in a large country like Brazil, local levels of resistance need therefore to be monitored by the authorities and reassessment and adjustments of regional doses of insecticides should be implemented as a public policy, to prevent massive spread of insecticides in the field, as well as increases in cases of resistance.

RESUMO Plutella xylostella causa graves danos em plantas crucíferas em todo o mundo. Agricultores em várias regiões do Brasil relatam uma crescente ineficiência no controle químico, mesmo com o uso de altas concentrações de inseticidas. O objetivo deste trabalho foi avaliar a suscetibilidade de populações brasileiras da traça-das-crucíferas aos inseticidas Premio® (Chlorantraniliprole), Dipel® (Bacillus thuringiensis var. kurstaki) e Lannate® BR (Metilcarbamato de oxina), frequentemente usados no Brasil. Os bioensaios de suscetibilidade foram realizados com cinco populações de traça-das-crucíferas coletadas em campo e duas de laboratório e foram conduzidos com concentrações crescentes de inseticidas até dez vezes acima da concentração recomendada. Resistências extremamente altas e dependentes da região foram encontradas em populações de campo para o Chlorantraniliprole e B. thuringiensis, com Razões de Resistência de até 370,0 vezes para a população de Camocin de São Felix . Para Metilcarbamato de oxina, não foi possível realizar a análise Probit para as populações de campo devido baixa mortalidade. Populações de laboratório demonstraram resistência aos três inseticidas testados com concentrações de CL50 excedendo as doses recomendadas em pelo menos 3,0 vezes. Os resultados demonstraram resistência forte e variável aos três inseticidas testados de acordo com a região de origem. Para manter o controle de pragas eficiente em um país grande como o Brasil, os níveis locais de resistência precisam ser monitorados pelas autoridades e reavaliações e ajustes de doses regionais dos inseticidas deveriam ser implementadas como política pública para evitar a disseminação massiva de inseticidas em campo, assim como, aumentos dos casos de resistência.

Abstract Pseudomonas aeruginosa is a non-lactose fermenting Gram-negative bacteria responsible for causing numerous nosocomial infections. The present research aimed to analyze the anti-Pseudomonas aeruginosa potential of 2-Chloro-N-(4-fluoro-3-nitrophenyl)acetamide (A8). The antibacterial potential of A8 was evaluated from the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Association using the checkerboard method. MIC and MBC values were 512 µg/mL for all P. aeruginosa strains evaluated, demonstrating predominantly bactericidal activity. Furthermore, when A8 was associated with the drug ceftriaxone, pharmacological additivity and indifference were evidenced. In this sense, the synthetic amide was interesting, since it demonstrates the potential to become a possible candidate for an antimicrobial drug.

Resumo Pseudomonas aeruginosa é uma bactéria Gram-negativa não fermentadora de lactose, responsável por causar inúmeras infecções nosocomiais. A presente pesquisa teve como objetivo analisar o potencial anti-Pseudomonas aeruginosa da molécula 2-Cloro-N-(4-fluoro-3-nitrofenil)acetamida (A8). O potencial antibacteriano do A8 foi avaliado a partir da Concentração Inibitória Mínima (CIM), Concentração Bactericida Mínima (CBM) e Associação pelo método de checkboard. Os valores de CIM e CBM foram de 512 µg/mL para todas as cepas de P. aeruginosa avaliadas, demonstrando atividade predominantemente bactericida. Além disso, quando o A8 foi associado ao fármaco ceftriaxona, evidenciou-se aditividade e indiferença farmacológica. Nesse sentido, a amida sintética se mostrou interessante, pois demonstra potencial para se tornar um possível candidato a fármaco antimicrobiano.

Abstract The aim of this study was to determine the acute toxicity of the essential oils (EOs) of Aloysia triphylla, Lippia gracilis and Piper aduncum in juvenile tambaqui (Colossoma macropomum), and evaluate the possible histopathological alterations in their gills. For the acute toxicity tests, juvenile tambaqui (n=24/treatment) were distributed in six treatments with three replicates, which comprised the control and five EO concentrations of A. triphylla (60, 80, 100, 120 and 140 mg L-1), L. gracilis (35, 40, 45, 50 and 55 mg L-1) and P. aduncum (42.5, 45, 47.5, 50 and 52.5 mg L-1), with an exposure period of 4 h. The mortality rate and severity of damage to the tambaqui gills were proportional to the increase in the concentration of the EO, with LC50-4 h values estimated at 109.57 mg L -1 for A. triphylla, 41.63 mg L -1 for L. gracilis and 48.17 mg L -1 for P. aduncum. The main morphological damages observed in the gills of the tambaqui exposed to the three EOs, were Grade I: hypertrophy and hyperplasia of lamellar epithelial cells, lamellar fusion, epithelial detachment, capillary dilation and constriction, proliferation of chloride cells and mucosal cells and edema; in low frequency Grade II damage as epithelial rupture and lamellar aneurysm. Necrosis (Grade III damage) was observed only in gill lamellae exposed to P. aduncum EO (47.5, 50.0 and 52.5 mg L-1). Concentrations of EOs below LC50-4 h can be used sparingly, for short periods of exposure for the treatment of diseases in tambaqui breeding.

Resumo O objetivo deste estudo foi determinar a toxicidade aguda dos óleos essenciais (OEs) de Aloysia triphylla, Lippia gracilis e Piper aduncum em juvenis de tambaqui (Colossoma macropomum), e avaliar as possíveis alterações histopatológicas em suas brânquias. Para os testes de toxicidade aguda, juvenis de tambaqui (n=24/tratamento) foram distribuídos em 6 tratamentos, com três repetições, sendo o controle e cinco concentração do OE de A. triphylla (60, 80, 100, 120 e 140 mg L-1), L. gracilis (35, 40, 45, 50 e 55 mg L-1) e P. aduncum (42,5, 45, 47,5, 50 e 52,5 mg L-1), com exposição de 4 h. A taxa de mortalidade e a severidade dos danos nas brânquias de tambaqui foram proporcionais ao aumento da concentração do OE, com os valores de CL50-4 h estimados em 109,57 mg L-1 para A. triphylla, em 41,63 mg L-1 para L. gracilis e em 48,17 mg L-1 para P. aduncum. Os principais danos morfológicos observados nas brânquias de tambaqui, expostos aos três OEs, foram os de grau I: hipertrofia e hiperplasia das células do epitélio lamelar, fusão lamelar, descolamento epitelial, dilatação e constrição capilar, proliferação de células de cloreto e de células mucosas e edema; em baixa frequência os de grau II como ruptura epitelial e aneurisma lamelar. Necrose (dano de grau III) foi observado somente nas lamelas branquiais expostas ao OE de P. aduncum (47,5, 50,0 e 52,5 mg L-1). Concentrações do OEs abaixo dos valores de CL50-4 h podem ser utilizados com parcimônia, em curtos períodos de exposição para o tratamento de doenças na criação de tambaqui.

Currently, there is a severe shortage of good-quality feldspar deposits. On the other hand, porcelain tile polishing residue has been widely recognized as an alternative raw material for the ceramic industry. Thus, this research evaluated the effect of the partial replacement of feldspar by the porcelain polishing residue (PPR) in formulations for sanitary stoneware. It was replaced from 2% to 20% of the total mass of feldspar by the residue. The raw materials were characterized by X-ray fluorescence, X-ray diffraction, and particle size determination. Then, they were mixed in a wet ball mill, and the rheological properties of the suspensions were analyzed. Samples of the test were produced by slip casting and sintered at 1160 °C, 1180 °C, and 1200 °C. Rheological characteristics were not affected when up to 20% of feldspar was replaced by residue. Bodies with high amounts of PPR had flexural strength and water absorption values similar to those of bodies without PPR in formulations. Furthermore, apparent porosity values lower than the reference mass were obtained with the addition of 6% of the residue in the formulation.

Abstract Alumina is a polymorphic bioceramic that has been extensively investigated for application in bone regeneration. Dense α-alumina has been considered a suitable biomaterial for dental and orthopedic implants due to its superior mechanical properties. However, its use is limited due to its high inertia in a biological environment. Recent investigations have focused on its distinct phases and surface characteristics through the control of morphology, physical properties, and chemical composition to enhance bioactivity. This article presents a brief review of the developments in porous α-alumina and amorphous-γ-alumina transition. Most studies have shown that composites and alumina coated with bioactive materials, high surface area, and hydroxylated surface can significantly improve biological properties. Cellular responses such as fixation, growth, and proliferation, as well as biomineralization, are the main studies to validate improvements in bioactive properties.

ABSTRACT The elephant grass (Cenchrus purpureus (Schumach.) Morrone) is one of the species with great prominence for energy production because of its favorable traits, such as high yield and short cycle, combined with several biomass quality characteristics. Therefore, this study intended to evaluate the morpho-agronomic traits of eight elephant grass genotypes under different cutting ages. A randomized block design with three replicates was applied to the experiment, and plots were composed of a 12 m long line divided into six subplots for each of the bimonthly cuts. Eight genotypes were evaluated in the plots, and the cutting ages (2, 4, 6, 8, 10, and 12-mo) were analyzed in the subplots. The following traits were assessed: DM yield, (DMY) percentage of DM, and average plant height (HEI). All genetic-statistical analyses were conducted using the Genes Program. The evaluated genotypes showed nonsignificant differences, indicating that, for the evaluated traits, these genotypes are genetically similar. Most genotypes presented linear effect of 2nd degree in the two assessment cuts, pointing they did not reach their maximum capacity of DMY in the time interval of the evaluated cuts. The maximum %DM achieved for the most genotypes occurred at about 9-mo age, while genotypes Vruckwona and BAG-86 at about 10-mo age. The maximum points for HEI trait were between 8 and 10-mo age. Increasing the cutting interval leads to increases in DM yield, with the 10-mo cutting age being the most efficient, resulting in higher yields.

Abstract Antarctic harsh conditions favor the development of microbial adaptations. In this study, a molecular approach was applied to identify/refine the taxonomy of five yeasts isolated from different Antarctic samples, which were tested against ranges of temperature, UV radiations, salinity, and pH. Based on sequencing and phylogenetic analysis, strain CRM 1839 was confirmed as Naganishia sp., and strains CRM 1874, CRM 1565, CRM 2571, and CRM 2576 were identified as Goffeauzyma gilvescens, Goffeauzyma gastrica, Candida atlantica, and Camptobasidium sp., respectively, being this last one possibly a new species. Growth at different temperatures indicates that these yeasts are psychrotolerant, with the exception of Camptobasidium sp., which presents psychrophilic characteristics. G. gastrica recovered from marine sediment showed the best results of resistance to UV radiation, being able to grow even after the exposure to UVB dose of 9144 J/m² and UVC dose of 6102 J/m². C. atlantica isolated from glacier soil showed high cellular growth from 3 to 10% NaCl. The majority of the strains produced higher biomass at pH 7; nevertheless, G. gilvescens showed higher biomass production at pH 9. The studied Antarctic-derived yeasts have adaptations to extreme conditions, which makes them useful for biotechnological applications and studies of extremophiles.

Resumo A produção de mudas de gravioleira na região semiárida do Brasil tem enfrentado limitações devido às elevadas concentrações de sais nas águas, sendo necessário o uso de técnicas que viabilizem seu cultivo, destacando-se a aplicação do peróxido de hidrogênio. Neste contexto, objetivou-se avaliar as formas de aplicação do peróxido de hidrogênio como atenuante do estresse salino nas trocas gasosas e no crescimento de mudas de gravioleira cv. Morada Nova. O estudo foi conduzido sob condições de casa de vegetação, em um Neossolo Regolítico de textura franco-arenosa, utilizando-se o delineamento inteiramente casualizado, no arranjo fatorial 5 × 4, cujos tratamentos resultaram da combinação de cinco níveis de condutividade elétrica da água de irrigação - CEa (0,6 - testemunha; 1,2; 1,8; 2,4 e 3,0 dS m-1) e quatro formas de aplicação de peróxido de hidrogênio (M1- sem aplicação de H2O2, M2 - aplicação via embebição das sementes, M3 -aplicação por pulverização foliar e M4 - aplicação via embebição das sementes + pulverização foliar), com quatro repetições e duas plantas por unidade experimental, perfazendo o total de 160 plantas. A concentração de H2O2 utilizada nas diferentes formas de aplicação foi de 20 µM. A salinidade da água de irrigação a partir de 0,6 dS m-1 diminuiu as trocas gasosas e o crescimento das plantas de gravioleira. O método de aplicação do H2O2 via pulverização foliar minimizou o efeito do estresse salino sobre as trocas gasosas. O método de aplicação do H2O2 via embebição das sementes diminuiu o estresse salino no crescimento de gravioleira aos 85 dias após o semeio.

Abstract The production of soursop seedlings in the Northeast region of Brazil has faced limitations due to the high concentrations of salts in the water, so it is necessary to use techniques that enable its cultivation, and the application of hydrogen peroxide to minimize the deleterious effects of salt stress stands out. In this context, the objective was to evaluate forms of application of hydrogen peroxide as an attenuator of salt stress on the gas exchange and growth of soursop seedlings cv. Morada Nova. The experiment was conducted under greenhouse conditions, in an Regolithic Neosol of sandy loam texture, from the municipality of Lagoa Seca - PB. A completely randomized design was used in a 5 × 4 factorial arrangement, whose treatments resulted from the combination of five levels of electrical conductivity of irrigation water - ECw (0.6 – control, 1.2, 1.8, 2.4 and 3.0 dS m-1) and four forms of hydrogen peroxide application (M1 - without H2O2 application, M2 - application by seed soaking, M3 - application by foliar spraying, and M4 - application by seed soaking + foliar spraying), with four replicates and two plants per experimental unit, totaling 160 plants. The concentration of H2O2 used in the different forms of application was 20 µM. Irrigation water salinity from 0.6 dS m-1 reduced the gas exchange and growth of soursop. The method of H2O2 application by foliar spraying minimized the effects of salt stress on gas exchange. The method of H2O2 application by seed soaking reduced the effect of salt stress on the growth of soursop at 85 days after sowing.

This work focuses on the validation and application of solid phase extraction followed by high-performance liquid chromatography (SPE-HPLC) analysis of important endocrine disruptors compounds (EDC) from different classes in highly complex wastewater matrix. The endocrine disruptors investigated included three different categories: pharmaceuticals (sulfamethoxazole (SMZ), trimethoprim (TMP) and diclofenac (DCF)), hormones (estrone (E1), 17α-ethinylestradiol (EE2) and 17β-estradiol (E2)) and plastic materials (bisphenol A (BPA)). The method involves pre-concentration by SPE using Strata-X extraction cartridges followed by HPLC coupled with diode array detector (DAD). As the assumption of homoscedasticity was met for analytical data, ordinary linear regression procedure was applied to the data. The method was considered validated for 7 EDC after consistent evaluation of the key analytical parameters. Recoveries were ranged from 52.3 to 179.6%. Limits of quantification were in the range 6.0-0.4 µg L−1. The described method was applied to evaluate the occurrence and removal efficiency of EDC in two biological sewage treatment plants (STPs). The influent mean concentrations of E1, E2 and EE2 hormones were 79.54; 175.09 and 102.19 µg L−1, respectively, while for SMZ, TMP, DCF and BPA were 215.17; 187.01; 218.97 and 87.12 µg L−1 for STP A, respectively. The efficiencies for the removal of EDCs ranged from 0 to 79.4%.

Resumo O objetivo deste estudo foi construir um modelo preditivo que utiliza a análise estatística de árvore de classificação para predizer a ocorrência de disfunção temporomandibular, dividindo a amostra em grupos de alto e baixo risco para o desenvolvimento da doença. A utilização de abordagens estatísticas preditivas que facilitem o processo de reconhecimento e / ou previsão da ocorrência de disfunção temporomandibular é de interesse da comunidade científica, com o objetivo de fornecer aos pacientes soluções mais adequadas a cada caso. Trata-se de um estudo transversal analítico de base populacional que envolveu uma amostra de 776 indivíduos que procuraram atendimento médico ou odontológico nas Unidades de Saúde da Família de Recife, PE, Brasil. A amostra foi submetida à anamnese por meio do instrumento Research Diagnostic Criteria for Temporomandibular Disorders. Os dados foram inseridos no software Statistical Package for the Social Sciences 20.0 e analisados pelo teste Qui-quadrado de Pearson para análise bivariada e pelo método de árvore de classificação para análise multivariada. A desordem temporomandibular pode ser prevista pela presença da dor orofacial, idade e depressão. O grupo de alto risco foi composto por indivíduos com dor orofacial, entre 25 e 59 anos e que apresentavam depressão. O grupo de baixo risco foi composto por indivíduos sem dor orofacial. Os autores puderam concluir que o melhor preditor para a disfunção temporomandibular foi a dor orofacial e que o modelo preditivo proposto pela árvore de classificação pode ser aplicado como ferramenta para simplificar a tomada de decisão em relação à ocorrência de disfunção temporomandibular.

Abstract The aim of this study was to construct a predictive model that uses classification tree statistical analysis to predict the occurrence of temporomandibular disorder, by dividing the sample into groups of high and low risk for the development of the disease. The use of predictive statistical approaches that facilitate the process of recognizing and/or predicting the occurrence of temporomandibular disorder is of interest to the scientific community, for the purpose of providing patients with more adequate solutions in each case. This was a cross-sectional analytical population-based study that involved a sample of 776 individuals who had sought medical or dental attendance at the Family Health Units in Recife, PE, Brazil. The sample was submitted to anamnesis using the instrument Research Diagnostic Criteria for Temporomandibular Disorders. The data were inserted into the software Statistical Package for the Social Sciences 20.0 and analyzed by the Pearson Chi-square test for bivariate analysis, and by the classification tree method for the multivariate analysis. Temporomandibular disorder could be predicted by orofacial pain, age and depression. The high-risk group was composed of individuals with orofacial pain, those between the ages of 25 and 59 years and those who presented depression. The low risk group was composed of individuals without orofacial pain. The authors were able to conclude that the best predictor for temporomandibular disorder was orofacial pain, and that the predictive model proposed by the classification tree could be applied as a tool for simplifying decision making relative to the occurrence of temporomandibular disorder.

RESUMO O objetivo do trabalho consistiu em determinar o efeito do óleo de alecrim (Rosmarinus officinalis) na qualidade sanitária e fisiológica de sementes de feijão fava (Phaseolus lunatus), utilizando as cultivares ‘Raio de Sol’, ‘Rosinha’ e ‘Roxinha’. Os tratamentos foram constituídos pelo fungicida Captan® (240 g. 100 kg-1 de sementes), óleo essencial de alecrim nas concentrações 0,25; 0,5; 0,75 e 1,0 mL L-1 diluídos em água destilada e esterilizada, acrescidos de 0,05 mL de Tween 20 e testemunha (sementes não tratadas). Foi utilizado o método de incubação com substrato de papel de filtro “Blotter test” para análise sanitária das sementes. A qualidade fisiológica foi determinada com base nos resultados de primeira contagem da germinação, índice de velocidade de germinação, comprimento e massa seca da parte aérea e raiz de plântulas. Foram identificados os géneros Fusarium sp., Cladosporium sp., Penicillium sp., Colletotrichum sp., Aspergillus sp., Nigrospora sp., Curvularia sp., Botrytis sp., Bipolaris sp. e Phytophthora sp. O óleo de alecrim foi eficiente na redução da incidência dos fungos associados a sementes e não interfere na germinação e crescimento inicial de feijão fava nas cultivares ‘Raio de Sol’, ‘Rosinha’ e ‘Roxinha’, independente das concentrações avaliadas.

ABSTRACT The objective of this work was to determine the effect of rosemary oil (Rosmarinus officinalis) on seed physiological and sanitary quality of lima bean seeds (Phaseolus lunatus), cultivars ‘Raio de Sol’, 'Rosinha' and 'Roxinha'. The treatments were composed of the Captan fungicide (240 g. 100 kg-1 of seeds), rosemary essential oil at 0.25; 0.5; 0.75 and 1.0 mL L-1 diluted in distilled and sterilized water, plus 0.05 mL of Tween 20 and control (untreated seeds). For sanitary analysis, the filter paper method (Blotter test) was used. The physiological quality was determined based on the results of first germination counting, germination, germination speed index, length and dry matter of shoot and seedling root. . The identified fungi genera were Fusarium sp., Cladosporium sp., Penicillium sp., Colletotrichum sp., Aspergillus sp., Nigrospora sp., Curvularia sp., Botrytis sp., Bipolaris sp. and Phytophthora sp. The rosemary oil was efficient in reducing the incidence of associated fungi and did not interfere with the lima bean germination and initial growth in 'Raio de Sol', 'Rosinha' and 'Roxinha' cultivars at the evaluated concentrations.

Resumo Devido à importância ecológica de Lophiosilurus alexandri, o presente trabalho avaliou sua representatividade genética, comparando estoques selvagens com plantéis de reprodutores de três larviculturas ao longo do Rio São Francisco. Noventa e sete amostras foram genotipadas com marcadores microssatélites recém-desenvolvidos. Baixos níveis de diversidade genética (número médio de alelos de 4,2) foram detectados em todos os casos, sendo mais severo no cativeiro. Os valores de FST e DEST par a par, as análises do Structure e DAPC mostraram a estruturação dos animais selvagens em dois grupos, e um terceiro formado pelas larviculturas, evidenciando a necessidade de adoção de critérios genéticos para retenção da diversidade genética no cativeiro. Por essa razão, três famílias de irmãos completos foram construídas para selecionar o melhor estimador de parentesco para a espécie e estabelecer os valores mínimos de corte para evitar cruzamentos indesejados. Dois estimadores, Wang (RW) e Lynch & Li (RLL), foram eficientes em refletir as relações de parentesco para irmãos completos nessa espécie. Segundo eles, menos de 50% dos potenciais cruzamentos são recomendáveis nas três larviculturas. A baixa diversidade genética inerente ao L. alexandri destaca a importância de minimizar a consanguinidade e evitar perda de diversidade genética, visando a recuperação da espécie.

Abstract Due to the ecological importance of Lophiosilurus alexandri, the present work evaluated its genetic representativeness by comparing wild stocks to broodstocks that were kept at three restocking hatcheries along the São Francisco River. A total of 97 samples were genotyped for newly developed microsatellite markers. Low levels of genetic diversity (average alleles number of 4.2 alleles) were detected in all cases, being more severe in captive groups. Significant pairwise FST and DEST values, Structure, and DAPC analyses showed that wild animals were structured in two groups, and a third group was formed by captive animals, evidencing the need to adopt genetic criteria to retain genetic diversity in the hatcheries. For this reason, three full-sib families were constructed to select the best relatedness estimator for L. alexandri and establish a cut-off value aimed to avoid full-sibling matings in the hatcheries. Two estimators, Wang (RW) and Lynch & Li (RLL), were accurate in reflecting the relatedness level for full-sibs in this species. According to them, less than 50% of the potential breeding matings in the three hatcheries are advisable. The innate low diversity of L. alexandri highlights the importance of minimizing inbreeding and retaining genetic diversity towards the species recovery.

[Ag(HL)NO3] complexes (1-4) were obtained with (E)-N’-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)acetohydrazide (HL1); (E)-N’-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)benzohydrazide (HL2); (E)-2-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)hydrazinecarbothioamide (HL3) and (E)-N-methyl-2-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)hydrazinecarbothioamide (HL4) secnidazole-derived Schiff bases. In addition, complexes [Bi(HL3)Cl3] (5) and [Bi(HL4)Cl3] (6) were also prepared. The silver(I) complexes (1-4) showed antifungal activity against Candida fungal strains while the uncomplexed ligands and the bismuth(III) complexes (5-6) were inactive, suggesting that the antifungal effects are probably due to the presence of silver. Although the Schiff base ligands and complexes (1-6) revealed to be inactive against Gram-positive and Gram-negative aerobic bacteria, all compounds exhibited potent antimicrobial effects against several anaerobic bacterial strains, indicating that their mode of action probably involves anaerobic bio reduction of the nitro group, with formation of metabolites which are toxic to the microorganisms. Electrochemistry studies showed that bio reduction of the nitro group is favored in complexes (1-6) in comparison to the free ligands, which might, at least in part, explain their increased antimicrobial effects.