Hydrogen-designed spin-states of 2D silicon carbide and graphene nanostructures.

Identifying and manipulating spin in two-dimensional materials is of great interest in advancing quantum information and sensing technologies, as well as in the development of spintronic devices. Here, we investigate the influence of hydrogen adsorption on the electronic and magnetic properties of graphene-like triangulenes. We have constructed triangulenes from SiC monolayers, which have been successfully synthesized very recently, extending our investigation to include graphene triangulenes. This advancement in the synthesis of SiC monolayers allows us to investigate deeper into the unique properties of SiC-based triangulenes and compare them with their graphene counterparts. The addition of hydrogen has been found to induce a magnetic moment in the SiC monolayer, with a more localized spin density when H is adsorbed in the C sites while spreading through the lattice when adsorbed on the Si sites. In triangular flakes, the ground spin state changes with the adsorption site: decreasing multiplicity on edge-defined sublattices and increasing it on the opposite sublattice. These findings suggest hydrogen adsorption as a tool for tuning spin-state properties in SiC and graphene nanostructures, with potential applications in spintronics and spin quantum dot devices.

Spatial distribution of the sport fishing in the state of Amazonas, northern Brazil.

The objective of this study was to spatialize sport fishing operations and assess the frequency of the use of the fishing areas in the state of Amazonas by combining the Geographic Information System (GIS) approach and information available in the documents sent to the Instituto de Proteção Ambiental do Amazonas (IPAAM). Information on sport fishing tourism operations was gathered from the IPAAM database and fishing licenses (FLs). Data analysis was conducted utilizing descriptive analysis, and the spatialization of the locations was performed using Q-GIS software. From 2002 to August 2021, 163 requests for FLs were made. There was a decrease in the amount of first time FL requests, with a peak in 2018 and 2019, N=17 and N=18, respectively. The activity is conducted in 24 municipalities, with Barcelos (31.36%) and Presidente Figueiredo (17.75%) being the most popular. At the sub-basin level, sport fishing is notably present in the Negro, Amazonas, Aripuanã, Madeira, Purus and Solimões River basins. Overall, 26.38% of operations take place in conservation areas, specifically in sustainable development reserves (SDRs). Barcelos recorded the largest number of rivers used, with 15 rivers. These results can support future proposals for the sustainable management of fisheries through the zoning of fishing areas in the state of Amazonas.

Trophic ecology of Acestrorhynchus falcirostris Cuvier, 1819 in island lakes on the lower stretch of the Solimões River, Amazon Basin / Ecologia trófica de Acestrorhynchus falcirostris Cuvier, 1819 em lagos de ilha no trecho inferior do Rio Solimões, Bacia Amazônica

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.

Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.

Trophic ecology of Acestrorhynchus falcirostris Cuvier, 1819 in island lakes on the lower stretch of the Solimões River, Amazon Basin

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.

Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.

Influence of abiotic factors on the composition of fish assemblages in the Aracá-Demeni sub-basin of the middle Negro River.

We evaluated the influence of flooding and receding comparison and spatial variation on the composition and structure of fish assemblages in blackwater and clearwater rivers of the Aracá-Demeni sub-basin in the middle Negro River, Amazonas state, Brazil. The collections were carried out during the falling-water period (November 2018) and the rising-water period (April 2019) using gillnets with meshes ranging from 30 to 120mm stretched mesh size. Ecological estimates of richness, equitability, the Shannon-Wiener diversity index, and the Berger-Parker index showed no significant differences between the periods. The composition of the ichthyofauna showed variations between the falling-water and rising-water periods. Beta diversity in the Aracá-Demeni sub-basin is almost completely caused by species substitution, with spatial turnover accounting for most of the estimate. The identification of these patterns and of the responsible factors are fundamental for the definition of conservation strategies, especially in an ecosystem whose dynamics can be influenced by climate change through changes in the intensity of the flood pulse and connectivity.

Impact of adding different concentrations of IGF-I and insulin to the semen extender on bull sperm quality post-cryopreservation / [Impacto da adição de diferentes concentrações de IGF-I e insulina ao diluidor de sêmen sobre a qualidade espermática bovina após a criopreservação]

ABSTRACT This study aimed to evaluate the addition of different concentrations of IGF-I and insulin to egg yolk-based extender to improve bovine semen cryopreservation. Two experiments were developed to evaluate the effects of the additives in two commercial extenders, Botubov® (Experiment 1) and Triladyl® (Experiment 2), both with the same design. Three ejaculates from four bulls (n = 12) were used. Each ejaculate was divided into seven equal fractions for dilution (60x106 spermatozoa/mL) in the following treatments: CON: extender only; IGF100: IGF-I 100ng/mL; IGF200: IGF-I 200ng/mL; INS150: insulin 150µUI/mL; INS200: insulin 200µUI/mL; ASS1: IGF-I 100ng/mL + insulin 150µUI/mL; ASS2: IGF-I 200ng/mL + insulin 200µUI/mL. Semen was cryopreserved by an automated system. Post-thawed sperm were evaluated regarding motility by CASA (Computer-assisted sperm analysis), and membranes by fluorescent probes (H342, PI, FITC-PSA and JC-1). For Botubov® extender, INS150 was more efficient in preserving total and progressive motility, VCL, BCF, plasma and mitochondrial membranes. A similar response was seen when insulin was added to the Triladyl® extender, INS150 was more efficient in preserving sperm motility, plasma membrane integrity and mitochondrial potential. Thus, the addition of insulin 150µUI/mL, regardless of the composition of the extender, contributes to better preserving bovine sperm from the cryopreservation effects.

RESUMO Este estudo teve o objetivo de avaliar a adição de diferentes concentrações de IGF-I e insulina a diluidores, à base de gema de ovo, para melhorar a criopreservação do sêmen bovino. Dois experimentos foram desenvolvidos para avaliar os efeitos dos aditivos em dois diluidores comerciais: Botubov® (Experimento 1) e Triladyl® (Experimento 2), ambos com o mesmo delineamento. Foram utilizados três ejaculados de quatro touros (n=12). Cada ejaculado foi dividido em sete frações para diluição (60x106espermatozoides/mL), nos seguintes tratamentos: CON: somente diluidor; IGF100: 100ng/mL de IGF-I; IGF200: 200ng/mL de IGF-I; INS150: 150µUI/mL de insulina; INS200: 200µUI/mL de insulina; ASS1: 100ng/mL de IGF-I + 150µUI/mL de insulina; ASS2: 200ng/mL de IGF-I + 200µUI/mL de insulina. O sêmen foi criopreservado por sistema automatizado. Após a criopreservação, o sêmen foi avaliado quanto à motilidade espermática por CASA e quanto às membranas espermáticas (plasmática, acrossomal e mitocondrial) por sondas fluorescentes (H342, PI, FITC-PSA e JC-1). Para o diluidor Botubov®, INS150 foi mais eficiente em preservar motilidades total e progressiva, VCL, BCF, integridade da membrana plasmática e potencial mitocondrial. Resposta semelhante foi observada quando a insulina foi adicionada ao diluidor Triladyl®, INS150 foi mais eficiente na preservação da motilidade, integridade das membranas e potencial mitocondrial quando comparado aos demais grupos. Assim, a adição de 150µUI/mL de insulina aos diluidores, independentemente da composição, contribui para melhor criopreservação dos espermatozoides bovinos.

Semen collection using electroejaculation and sperm parameters in pacas (Cuniculus paca, Linnaeus, 1766) / Coleta de sêmen com uso da eletroejaculação e parâmetros espermático em pacas (Cuniculus paca, Linnaeus, 1766)

Pacas (Cuniculus paca) are highly hunted animals because of the flavor of their meat, and commercial breeding is recommended. However, this species has a relatively low reproductive rate. This study aimed to collect semen from pacas through electroejaculation and obtain the sperm parameters of this species for the first time. Seven male pacas were used, submitted to an anesthetic protocol before stimulation by an electroejaculator appropriate for the species. The stimulus protocol was performed in three series: series I, 10 stimuli with 1 and 2 V; series II, 10 stimuli with 3 and 4 V; and series III, 10 stimuli with 5 V and interval between series of 2 s. The collected material was evaluated for color, volume, motility, vigor, and concentration. The sperm parameters collected showed a mean volume of 0.43±0.33 mL, concentration of 45.5±42.44×106 sperm/mL, motility of 33.33±32.14%, and mean vigor of 2.6±1.15. In this study, the anesthetic protocol did not seem to favor semen collection by electroejaculation in the pacas. The electrical stimulation protocol was able to stimulate all animals in the study; however, there were few samples with sperm cells and a low rate of motility and vigor in most ejaculates.

Pacas (Cuniculus paca) são animais altamente caçados devido ao sabor de sua carne, sendo a criação comercial delas, recomendada. Entretanto, é uma espécie com baixa taxa reprodutiva. O objetivo deste estudo foi efetuar coleta de sêmen em pacas por meio da eletroejaculação e da obtenção, pela primeira vez, dos parâmetros espermáticos dessa espécie. Foram utilizadas sete pacas machos, as quais, antes dos estímulos por eletroejaculador apropriado para a espécie, foram submetidas a protocolo anestésico. O protocolo de estímulo foi realizado em três séries: série I, 10 estímulos com 1 e 2V; série II, 10 estímulos com 3 e 4V; série III, 10 estímulos com 5V, e intervalo entre as séries de dois segundos. O material coletado foi avaliado quanto à cor, ao volume, à motilidade, ao vigor e à concentração. Os parâmetros espermáticos coletados demonstraram volume médio de 0,43±0,33mL, concentração de 45,5±42,44x106 espermatozoides/mL, motilidade de 33,33±32,14% e vigor médio de 2,6±1,15. Neste estudo, o protocolo anestésico parece não ter favorecido a coleta de sêmen por eletroejaculação em pacas. Entretanto, o protocolo de estímulos elétricos foi capaz de estimular todos os animais do estudo. Assim, chegou-se ao resultado de poucas amostras com a presença de células espermáticas, bem como baixo índice de motilidade e vigor na maioria dos ejaculados.

The consumption of fish by the riverine population of the lower Solimões River, Amazonas, Brazil.

The riverine population of the Amazon Basin are among the largest consumers of fish in the world, but the consumption patterns could be regionally distinct. Moreover, their total fish catches are not fully known. The objective of this work was to estimate the per capita fish consumption of the riverine people that inhabit the Paciência Island (Iranduba, Amazonas), where there is a fishing agreement in force. A total of 273 questionnaires were applied during the first two weeks of each month between April 2021 and March 2022. The sample unit was the residences. The questionnaire contained questions about the species captured and their quantities. Consumption was calculated by dividing the average monthly capture with the average number of residents per household interviewed, which was multiplied by the number of questionnaires applied. Thirty groups of consumed fish species belonging to 17 families and 5 orders were recorded. The total catch was 3,388.35 kg and the highest monthly catch was 602.60 kg during the falling-water season in October. Daily per capita fish consumption averaged 66.13 ± 29.21 g/day, with a peak of 116.45 g/day during the falling-water season in August. The high fish consumption rate highlighted the importance of fisheries management to food security and the maintenance of the community's lifestyle.

The consumption of fish by the riverine population of the lower Solimões River, Amazonas, Brazil / O consumo de pescado de uma população ribeirinha do baixo rio Solimões, Amazonas, Brasil

The riverine population of the Amazon Basin are among the largest consumers of fish in the world, but the consumption patterns could be regionally distinct. Moreover, their total fish catches are not fully known. The objective of this work was to estimate the per capita fish consumption of the riverine people that inhabit the Paciência Island (Iranduba, Amazonas), where there is a fishing agreement in force. A total of 273 questionnaires were applied during the first two weeks of each month between April 2021 and March 2022. The sample unit was the residences. The questionnaire contained questions about the species captured and their quantities. Consumption was calculated by dividing the average monthly capture with the average number of residents per household interviewed, which was multiplied by the number of questionnaires applied. Thirty groups of consumed fish species belonging to 17 families and 5 orders were recorded. The total catch was 3,388.35 kg and the highest monthly catch was 602.60 kg during the falling-water season in October. Daily per capita fish consumption averaged 66.13 ± 29.21 g/day, with a peak of 116.45 g/day during the falling-water season in August. The high fish consumption rate highlighted the importance of fisheries management to food security and the maintenance of the community's lifestyle.

As populações amazônicas são uma das maiores consumidoras de pescado do mundo, contudo os padrões de consumo podem ser regionalmente distintos. Além disso, as capturas totais não são totalmente conhecidas. O objetivo do trabalho foi estimar o consumo per capita e as capturas de pescado por ribeirinhos residentes na Ilha da Paciência (Iranduba, Amazonas), onde há um acordo de pesca vigente. Foram aplicados no total 273 questionários durante as duas primeiras semanas de cada mês entre abril de 2021 e março de 2022. A unidade amostral foram as residências. O questionário continha perguntas sobre as espécies capturadas e respectivas quantidades. O consumo foi calculado pela divisão entre a média de captura mensal com a média de moradores por residência entrevistada que foi multiplicada pelo número de questionários aplicados. Foram registrados 30 grupos de espécies de peixes consumidos pertencentes a 17 famílias e 5 ordens. A captura total foi de 3.388,35 kg e a maior captura mensal foi de 602,60 kg durante a vazante no mês de outubro. O consumo de pescado per capita diário foi em média 66,13 ± 29,21 g/dia, com pico de 116,45 g/dia durante a vazante no mês de agosto. A alta taxa de consumo de pescado mostra a importância do manejo pesqueiro para a segurança alimentar e a manutenção do estilo de vida da comunidade.

Relationship Between Pre-Slaughter Factors and Major Causes of Carcass Condemnation in a Broiler Slaughterhouse under Federal Inspection

This study aimed to investigate the relationship between pre-slaughter factors and major causes of total or partial carcass condemnation in a broiler slaughterhouse under federal inspection. Data on total and partial carcass condemnations between 2018 and 2020 were collected from 10 broiler farms supplying a slaughterhouse located in northern Paraná State, Brazil. The total sample comprised 2,562,642 birds. The pre-slaughter factors analyzed were age at slaughter, stocking density, weight at slaughter, feed conversion, and mortality.Associations between causes of condemnation and pre-slaughter factors were analyzed using a generalized linear model with negative binomial distribution, a generalized linear model with quasi-Poisson distribution, and a generalized linear mixed model with Poisson distribution. Total carcass condemnations were mostly due to repugnant appearance (48.67%) and arthritis (26.56%), whereas partial carcass condemnations were mainly due to arthritis (31.02%), bruising (27.97%), and myopathies (15.18%). Mean age and stocking density were the pre-slaughter factors that most contributed to increasing total and partial condemnation rates, indicating that reducing stocking density and age at slaughter might be important strategies for minimizing economic losses associated with carcass condemnation.(AU)

Influence of abiotic factors on the composition of fish assemblages in the Aracá-Demeni sub-basin of the middle Negro River / Influência de fatores abióticos na composição das assembleias de peixes na sub-bacia Aracá-Demeni no médio rio Negro

Abstract We evaluated the influence of flooding and receding comparison and spatial variation on the composition and structure of fish assemblages in blackwater and clearwater rivers of the Aracá-Demeni sub-basin in the middle Negro River, Amazonas state, Brazil. The collections were carried out during the falling-water period (November 2018) and the rising-water period (April 2019) using gillnets with meshes ranging from 30 to 120mm stretched mesh size. Ecological estimates of richness, equitability, the Shannon-Wiener diversity index, and the Berger-Parker index showed no significant differences between the periods. The composition of the ichthyofauna showed variations between the falling-water and rising-water periods. Beta diversity in the Aracá-Demeni sub-basin is almost completely caused by species substitution, with spatial turnover accounting for most of the estimate. The identification of these patterns and of the responsible factors are fundamental for the definition of conservation strategies, especially in an ecosystem whose dynamics can be influenced by climate change through changes in the intensity of the flood pulse and connectivity.

Resumo Avaliamos a influência da variação entre os períodos de enchente e vazante e espacialmente na composição e estrutura das assembleias de peixes em rios de águas pretas e claras da sub-bacia Aracá-Demeni no médio rio Negro, Amazonas, Brasil. As coletas foram realizadas durante o período de vazante (novembro de 2018) e o período de enchente (abril de 2019) utilizando redes de espera com malhas variando de 30 a 120mm entre nós opostos. As estimativas ecológicas de riqueza, equitabilidade, índice de diversidade de Shannon-Wiener e índice de Berger-Parker não apresentaram diferenças significativas entre os períodos. A composição da ictiofauna apresentou variações entre os períodos de vazante e enchente. A diversidade beta na sub-bacia Aracá-Demeni é quase totalmente causada pela substituição de espécies, com a renovação espacial respondendo pela maior parte da estimativa. A identificação desses padrões e os fatores responsáveis são fundamentais para a definição de estratégias de conservação, principalmente em um ecossistema cuja dinâmica pode ser influenciada pelas mudanças climáticas por meio de mudanças na intensidade do pulso de inundação e conectividade.

Perception of Amazonian fishers regarding environmental changes as causes of drastic events of fish mortality.

Events of catastrophic fish mortality in the lakes of the Amazonian floodplains are not uncommon. They are generally associated with thermal inversion of the water column, which is provoked by cold air masses that originate from the south of the continent. These events occur in the period of high water when the lakes are stratified. This paper reports an event of fish mortality that occurred during the low water season in a large floodplain system on the right-hand margin of the Amazon River. Information from seasoned fishers, who live in the same area where the event happened, and hydrological and satellite image analysis was used to identify the potential cause of fish mortality events. The amplitude of the flood pulse and the duration of extreme ebb showed to be the key factors responsible for the occurrence of events of fish mortality. These factors determine connectivity patterns between the floodplain lakes and the river channel, which are essential for maintaining water quality and the biota in the systems.

Differential gene expression pattern and plasma sex steroids during testicular development in Genyatremus luteus (Perciforme: Haemulidae) (Bloch, 1790).

The aim of the current study is to evaluate gene expression patterns of LH (lhr) and estrogen (er) receptors and plasma steroid levels during testicular development in Genyatremus luteus. Males were histologically classified as immature (n=7), maturing (n=7) and mature (n=7), based on the cellular structure of their testes. Plasma 11-KT concentration recorded peak at the final maturation stage. The highest plasma 17α-OHP concentrations were observed at the immature stage; they decreased at the maturation and mature stages. On the other hand, 17ß-estradiol (E2) recorded higher concentrations at the maturation stage. Er expression has significantly increased along the maturational development of animals' testes. The mRNA observed for the LH receptor has decreased from immature to maturing stage; it presented expression peak at the mature stage. There was high association between receptor gene expression and plasma steroid levels, mainly E2. The current study was the first to feature different reproductive maturation stages in male G. luteus specimens, based on cellular, endocrine and molecular aspects. In addition, it has shown that the gene expression profile for er and lhr receptors, as well as plasma 11-KT and E2 concentrations, are directly linked to testicular maturation, although they are not necessarily associated with the gonadosomatic index.

Reproductive performance of red-winged tinamous (Rhynchotus rufescens) using different mating strategies in captivity - case report / [Desempenho reprodutivo de perdizes (Rhynchotus rufescens) utilizando diferentes estratégias de acasalamento em cativeiro - relato de caso]

The aim of this study was to evaluate the reproductive performance of red-winged tinamous in captivity using different mating systems during three breeding seasons. The data were collected from August to March during three breeding seasons of the species. Ten couples and four groups of red-winged tinamous were randomly selected for formation of the monogamous and polygynous mating system, respectively, with egg collection from both systems. The traits evaluated were number of eggs per female, egg breaking and egg fertilization. Data were statistically analyzed by the least square method and logistic regression. Animals in couples mating strategy were superior (P<0.05) in terms of number of eggs per female compared to the group mating strategy. High egg breaking rate (P<0.05) in the red-winged tinamous groups was observed. Eggs of animals in couples mating strategy were 5.24 and 11.5 more likely to be fertilized than those of group strategy in two breeding seasons. In general, the reproductive efficiency in terms of low egg breaking, high egg production and fertility was observed for red-winged tinamous from the monogamous mating system.

O objetivo deste estudo foi avaliar o desempenho reprodutivo dos perdizes de asas vermelhas em cativeiro utilizando diferentes sistemas de acasalamento durante três épocas de reprodução. Os dados foram coletados de agosto a março, durante três épocas de reprodução da espécie. Dez casais e quatro grupos de perdizes de asas vermelhas foram selecionados aleatoriamente para a formação do sistema de acasalamento monogâmico e poliginoso, respectivamente, com coleta de ovos de ambos os sistemas. Os traços avaliados foram o número de ovos por fêmea, a quebra dos ovos e a fertilização dos ovos. Os dados foram analisados estatisticamente pelo método dos mínimos quadrados e pela regressão logística. Os animais na estratégia de acasalamento de casais foram superiores (P<0,05) em termos de número de óvulos por fêmea, em comparação com a estratégia de acasalamento do grupo. Foi observada uma alta taxa de quebra de ovos (P<0,05) nos grupos perdizes de asas vermelhas. Ovos de animais em estratégia de acasalamento de casais foram 5,24 e 11,5 mais propensos a serem fertilizados do que os de estratégia de grupo em duas épocas de reprodução. Em geral, a eficiência reprodutiva em termos de baixa quebra de ovos, alta produção de ovos e fertilidade foi observada para os tinâmicos de asas vermelhas do sistema de acasalamento monogâmico.

Perivascular mast cells and expression of vascular endothelial growth factor, laminin-332 and matrix metalloproteinase-9 in human colorectal neoplasms.

INTRODUCTION AND AIMS: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide, and significantly contributes to cancer-related deaths. Most cases arise from adenomatous polyps. Biomarkers currently play an important role in tumor progression. Our aim was to identify perivascular mast cells and analyze the expression of laminin-332, MMP-9, and VEGF in cases of adenoma and CRC in humans. MATERIALS AND METHODS: Patients were selected at the Coloproctology Service and samples were obtained through biopsies. Adenoma and CRC slides were examined, utilizing immunohistochemistry to detect molecules, and were processed, using 1% Alcian Blue (pH 0.5) for mast cell staining. RESULTS: Higher density of perivascular mast cells was observed in adenomas. Laminin-332 expression revealed basement membrane discontinuity associated with tumor invasion in CRC. MMP-9 immunostaining in adenoma was detected in glandular epithelium and lining epithelium, in areas close to the basement membrane, whereas in CRC, the enzyme was found in the cytoplasm of invasive clusters. VEGF expression was associated with cell atypia in adenoma and in areas of disorganization of the epithelium-connective tissue interface in CRC. VEGF has also been detected in endothelial cells from microvessels. CONCLUSIONS: We demonstrated the different patterns of perivascular mast cells and molecular expression in colorectal neoplasms. Those analyses favor the recognition of the predisposition to the disease, or its early stage, and have the potential to define the molecular profile of the lesions.

Physical and chemical aspects of the footbath from dairy farms with different production systems in Arapoti, Paraná / Aspectos físicos e químicos do pedilúvio de propriedades leiteiras com diferentes sistemas de produção, no município de Arapoti, Paraná

This study aimed to evaluate copper sulfate solutions at 5% and 10% concentrations in footbaths from three dairy farms (A, B and C) with free stall and compost barn production systems, located in the municipality of Arapoti, Parana, Brazil. Farms A, B and C were composed of 537, 88 and 208 lactating cows, respectively, all conditioned to the use of a footbath. Every seven days, before and after the passage of each batch of cows through the footbath, samples of the solution were collected for the evaluation of pH, temperature, and the volume of the solution measured. Farms A and C had higher pH alkalinization due to the greater number of batch passages, from the third batch onwards, and also a reduction in the volume of the solution. It is concluded that the volume varied both with the number of animals that passed through the footbath and with the deposition of organic matter in the solution. The concentration of 10% copper sulfate solution was not able to inhibit pH changes. Furthermore, there was no standardization in the dimensions of the footbaths on the farms.

Objetivou-se avaliar as soluções de sulfato de cobre nas concentrações de 5% e 10%, em pedilúvios de três propriedades leiteiras (A, B e C), com sistemas de produção "free stall" e "compost barn", localizadas no município de Arapoti, Paraná, Brasil. As propriedades A, B e C eram compostas por 537, 88 e 208 vacas em lactação, respectivamente, todas condicionadas ao uso do pedilúvio. A cada sete dias, antes e após a passagem de cada lote de vacas pelo pedilúvio, foram colhidas amostras da solução para a avaliação do pH, da temperatura e do volume. As propriedades A e C tiveram alcalinização maior do pH devido ao maior número de passagem de lotes, a partir do terceiro lote, com redução também do volume da solução. Conclui-se que o volume variou tanto com o número de animais que passaram pelo pedilúvio quanto com a deposição de matéria orgânica na solução. A concentração da solução de sulfato de cobre a 10% não foi capaz de inibir as alterações de pH. Além disso, não houve padronização das dimensões dos pedilúvios nas fazendas.

Trophic ecology of Acestrorhynchus falcirostris Cuvier, 1819 in island lakes on the lower stretch of the Solimões River, Amazon Basin.

The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.

Differential gene expression pattern and plasma sex steroids during testicular development in Genyatremus luteus (Perciforme: Haemulidae) (Bloch, 1790) / Padrão diferencial de expressão gênica e esteróides sexuais plasmáticos durante o desenvolvimento testicular em Genyatremus luteus (Pisces: Haemulidae) (Bloch, 1790)

The aim of the current study is to evaluate gene expression patterns of LH (lhr) and estrogen (er) receptors and plasma steroid levels during testicular development in Genyatremus luteus. Males were histologically classified as immature (n=7), maturing (n=7) and mature (n=7), based on the cellular structure of their testes. Plasma 11-KT concentration recorded peak at the final maturation stage. The highest plasma 17α-OHP concentrations were observed at the immature stage; they decreased at the maturation and mature stages. On the other hand, 17ß-estradiol (E2) recorded higher concentrations at the maturation stage. Er expression has significantly increased along the maturational development of animals' testes. The mRNA observed for the LH receptor has decreased from immature to maturing stage; it presented expression peak at the mature stage. There was high association between receptor gene expression and plasma steroid levels, mainly E2. The current study was the first to feature different reproductive maturation stages in male G. luteus specimens, based on cellular, endocrine and molecular aspects. In addition, it has shown that the gene expression profile for er and lhr receptors, as well as plasma 11-KT and E2 concentrations, are directly linked to testicular maturation, although they are not necessarily associated with the gonadosomatic index.

O objetivo deste estudo foi avaliar os padrões de expressão gênica dos receptores de LH (lhr) e de estrogênio (er) e dos níveis de esteróides plasmáticos durante o desenvolvimento testicular de Genyatremus luteus. Os machos foram classificados histologicamente em imaturos, em maturação e maduros, de acordo com a estrutura celular dos testículos. A concentração plasmática de 11-KT apresentou um pico na fase de maturação final (P<0.05). As maiores concentrações plasmáticas de 17α-OHP foram encontradas no estádio imaturo (P<0.05), com consequente diminuição nos estádios em maturação e maturo. O 17ß-estradiol (E2) apresentou maiores níveis de concentração no estádio em maturação (P<0.05). A expressão de er aumentou significativamente ao longo do desenvolvimento maturacional dos testículos (P<0.05). O mRNA para o receptor de LH diminuiu do estádio imaturo para o estádio em maturação (P<0.05) com consequente pico de expressão no estádio maduro. Houve alta relação entre a expressão gênica dos receptores e os níveis de esteróides plasmáticos, especialmente com E2. Em conclusão, este estudo caracterizou pela primeira vez, sob os aspectos celular, endócrino e molecular, os diferentes estádios de maturação reprodutiva em machos de G. luteus, demonstrando que o perfil da expressão gênica para os receptores er e lhr, bem como as concentrações plasmáticas de 11-KT e E2 foram diretamente relacionados à maturação testicular, apesar de não se relacionarem necessariamente com o índice gonadossomático.

Perception of Amazonian fishers regarding environmental changes as causes of drastic events of fish mortality / A percepção de pescadores amazônicos das mudanças ambientais como causas de drásticos eventos de mortalidade de peixes

Events of catastrophic fish mortality in the lakes of the Amazonian floodplains are not uncommon. They are generally associated with thermal inversion of the water column, which is provoked by cold air masses that originate from the south of the continent. These events occur in the period of high water when the lakes are stratified. This paper reports an event of fish mortality that occurred during the low water season in a large floodplain system on the right-hand margin of the Amazon River. Information from seasoned fishers, who live in the same area where the event happened, and hydrological and satellite image analysis was used to identify the potential cause of fish mortality events. The amplitude of the flood pulse and the duration of extreme ebb showed to be the key factors responsible for the occurrence of events of fish mortality. These factors determine connectivity patterns between the floodplain lakes and the river channel, which are essential for maintaining water quality and the biota in the systems.

Eventos catastróficos de mortalidade de peixes em lagos de várzea da Amazônia não são incomuns, sendo, em geral, associados com a inversão térmica da coluna d'água, que é provocada por massas de ar frio que se originam no sul do continente. Esses eventos ocorrem no período de águas altas quando os lagos estão estratificados. Nesse artigo, relata-se um evento de mortalidade de peixes que ocorreu durante a estação de águas baixas em um grande sistema de várzea situado na margem direita do rio Amazonas. Usou-se o relato de pescadores residentes na área onde ocorreu o evento e com experiência na pesca, em conjunto com dados hidrológicos e imagens de satélite, para identificar potenciais causas do evento de mortalidade de peixes e propõe-se que a amplitude do pulso de inundação e a duração de secas extremas são os fatores chaves para a ocorrência dos eventos de mortalidade de peixes. Esses fatores determinam padrões de conectividade entre os lagos de várzea e o canal do rio, os quais são essenciais para a manutenção da qualidade da água e da biota nesses sistemas.

Cobalt mediated electro-scrubbers for the degradation of gaseous perchloroethylene.

This work focuses on the treatment of gaseous perchloroethylene (PCE) using electro-scrubbing with diamond electrodes and cobalt mediators. PCE was obtained by direct desorption from an aqueous solution containing 150 mg L-1, trying to a real pollution case. The electro-scrubber consisted of a packed absorption column connected with an undivided electrochemical cell. Diamond anodes supported on two different substrates (tantalum and silicon) were used and the results indicated that Ta/BDD was more successful in the production of Co (III) species and in the degradation of PCE. Three experimental systems were studied for comparison purposes: absorbent free of Co (III) precursors, absorbent containing Co (III) precursors, and absorbent containing Co (III) precursors undergoing previous electrolysis to the electro-scrubbing to facilitate the accumulation of oxidants. The most successful option was the last, confirming the important role of mediated electrochemical processes in the degradation of PCE. Trichloroacetic acid (TCA) and carbon tetrachloride (CCl4) were found as the primary reaction products and ethyl chloroacetate esters were also identified. A comprehensive mechanism of the processes happening inside electro-scrubber is proposed.