Despite being considered beneficial by providing a clean and renewable source of energy, the construction of hydroelectric dams has extremely negative implications for Amazonian fisheries. This study ...investigated the impacts of the Santo Antônio and Jirau hydroelectric dams on the fishery stocks of the Madeira River. This investigation was based on fish catch data from the Z‐31 fishing colony, located in the municipality of Humaitá, in Amazonas State, Northern Brazil. Data were collected daily and provided information on the date of return from each trip, the fish species targeted, and the total catch (kg) between January 2002 and September 2017. The results indicated reductions of 39% in the mean annual catch and 34% in the mean monthly catches. These results highlight the high price paid by local fish communities for the development of hydroelectric power in the Amazon basin.
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► Tolypocladium spp. were evaluated for cold activity, heat, and UV-B tolerances. ► Tolypocladium cylindrosporum were the most cold active species. ► Tolypocladium inflatum and ...Tolypocladium geodes were less active to cold. ► Metarhizium robertsii did not germinate at 8±1°C. ► T. cylindrosporum ARSEF 5558 was more resistant to UV-B radiation and heat.
Studies on the stress resistance of insect-pathogenic fungi are very important to better understand the survival of these organisms in the environment. In this study, we examined the cold activity (8±1°C for 7days), UV-B tolerance (Quaite-weighted UV-B irradiance at 847.90mWm−2 for 1, 2, 3, and 4h), and wet-heat tolerance (45°C for 1, 2, 3, and 4h) of two isolates of Tolypocladiumcylindrosporum (ARSEF 3392 and 5558), one isolate of Tolypocladium geodes (ARSEF 3275), and two isolates of Tolypocladium inflatum (ARSEF 4772 and 4877) based on their germination, compared with Metarhizium robertsii (ARSEF 2575). After 3h of UV-B exposure, T. cylindrosporum germinated at a greater rate than the other Tolypocladium species and had similar viability to that of the M. robertsii. Most Tolypocladium isolates, however, were less UV-B tolerant than M. robertsii. The T.cylindrosporum isolates were also the most thermotolerant, with similar tolerance to the M. robertsii. The isolates of T. inflatum and T. geodes, which had similar heat tolerance, were the least heat tolerant compared with the isolates of T. cylindrosporum and M. robertsii. After 4h of heat exposure, the germination of T. inflatum and T. geodes isolates was not significantly different. For cold activity, both T.cylindrosporum isolates germinated to ca. 100% in only 3days. Approximately 50% of the two T. inflatum isolates germinated, and less than 5% of T. geodes germinated after 3days. All fungal isolates, however, completely germinated by the seventh day, except M.robertsii. The isolates of T. cylindrosporum, therefore, were the most heat and UV-B tolerant, and had the highest cold activity compared to the other species. The tolerance of M. robertsii to UV-B radiation and heat was similar to that of T.cylindrosporum.
Archaea and Bacteria constitute a majority of life systems on Earth but have long been considered inferior to Eukarya in terms of solute tolerance. Whereas the most halophilic prokaryotes are known ...for an ability to multiply at saturated NaCl (water activity (a(w)) 0.755) some xerophilic fungi can germinate, usually at high-sugar concentrations, at values as low as 0.650-0.605 a(w). Here, we present evidence that halophilic prokayotes can grow down to water activities of <0.755 for Halanaerobium lacusrosei (0.748), Halobacterium strain 004.1 (0.728), Halobacterium sp. NRC-1 and Halococcus morrhuae (0.717), Haloquadratum walsbyi (0.709), Halococcus salifodinae (0.693), Halobacterium noricense (0.687), Natrinema pallidum (0.681) and haloarchaeal strains GN-2 and GN-5 (0.635 a(w)). Furthermore, extrapolation of growth curves (prone to giving conservative estimates) indicated theoretical minima down to 0.611 aw for extreme, obligately halophilic Archaea and Bacteria. These were compared with minima for the most solute-tolerant Bacteria in high-sugar (or other non-saline) media (Mycobacterium spp., Tetragenococcus halophilus, Saccharibacter floricola, Staphylococcus aureus and so on) and eukaryotic microbes in saline (Wallemia spp., Basipetospora halophila, Dunaliella spp. and so on) and high-sugar substrates (for example, Xeromyces bisporus, Zygosaccharomyces rouxii, Aspergillus and Eurotium spp.). We also manipulated the balance of chaotropic and kosmotropic stressors for the extreme, xerophilic fungi Aspergillus penicilloides and X. bisporus and, via this approach, their established water-activity limits for mycelial growth (∼0.65) were reduced to 0.640. Furthermore, extrapolations indicated theoretical limits of 0.632 and 0.636 a(w) for A. penicilloides and X. bisporus, respectively. Collectively, these findings suggest that there is a common water-activity limit that is determined by physicochemical constraints for the three domains of life.
► Nitrogen PIII improved the hardness and elastic modulus of the PP acetylene films. ► Wettability of the films increased right after PIII, but it diminished in aging. ► The films treated with low to ...medium exposures times show highest elasticity index. ► These results are ascribed mainly to the increase in the chain crosslinking degree. ► In general, the degree of modifications depends on treatment time.
Thin films were prepared by plasma enhanced chemical vapour deposition (PECVD) from a mixture of acetylene and argon, and post deposition-treated by plasma immersion ion implantation (PIII). The effect of PIII on the nanofilms properties was evaluated as a function of treatment time. The average thickness and roughness were diminished upon PIII. On the other hand, hardness (0.7–3.9GPa) and elastic modulus (29–54GPa) increased upon 60min of ion bombardment. Such results are ascribed mainly to the densification of the film structure caused by the increment in the crosslinking degree with increasing the energy deposited in the films. Wettability of the samples, investigated by contact angle measurements, was reduced (from 64 to 21°) right after PIII. This result, attributed to the introduction of polar groups in the film structure, was not preserved as the sample was aged in atmosphere. After aging, contact angles were larger than 70° but still smaller than 90°. Although the wettability has decreased with aging, the hydrophilic character of the samples was preserved. For certain treatment times, nitrogen PIII turned the plasma-polymerized acetylene films smoother, denser, mechanically and tribologicaly more resistant than the as-deposited material.
The use of interdisciplinary approaches such as the proposed report provides a broad understanding of the relationship between people and the environment, revealing reliable aspects not previously ...considered in the study of this relationship. This study compiled evidence on the environmental degradation of an urbanized river over the past few decades, providing a diagnosis of the consequences of this process for the river, its ichthyofauna, and the local human population.
The study was focused on the Beira Rio community on the Capibaribe River in the municipality of São Lourenço da Mata, Pernambuco, Brazil. Data were collected using geoprocessing and ethnobiological approaches, as well as environmental parameters. This research was conducted with the most experienced long-term residents in the local community, through interviews and participatory methodologies to recovering information about the river environment, its ichthyofauna and its environmental services for the last decades.
According to the GIS analysis, the study area was subject to an accelerated process of urbanization, with the total urban area increasing from 73 565, 98 m(2) in 1974 to 383 363, 6 m(2) in 2005. The informants perceived the urban growth, especially in the late twentieth century, being this period recognized as the phase of greatest negative changes in the river environment. The perceived decline of fish stocks was indicated by the community as one of the effects of river degradation. According to the interviews, the deterioration of the river affected the ecosystem services and the relationship of the adjacent human community with this ecosystem. The environmental data indicated that the river is suffering eutrophization and has fecal coliform concentrations 160 times higher than the maximum level permitted by Brazilian legislation.
The interdisciplinary approach used in this research allowed the understanding of the degradation process of an urban river and some negative effects through the integration of environmental data, GIS and the local knowledge, revealing the complementarity of obtained data and the effectiveness of implementation of this approach.
RESUMO Este artigo apresenta os resultados da pesquisa “Desenvolvimento de metodologia para catalogação dos ambientes de um museu-casa, compreendidos como objetos museológicos”, desenvolvida no ...âmbito do Programa de Incentivo à Produção do Conhecimento Técnico e Científico na Área da Cultura da Fundação Casa de Rui Barbosa. A metodologia da pesquisa incluiu revisão bibliográfica e aplicação de questionários. Primeiramente discutimos a categoria museu-casa e a relevância do estudo dos interiores domésticos. Posteriormente, discutimos a concepção do cômodo enquanto museália e a importância do registro da trajetória social dos artefatos museológicos. Na quarta seção do artigo, apresentamos e refletimos sobre a coleção de cômodos-objetos do Museu Casa de Rui Barbosa, localizado em uma construção de 1850, que serviu de residência a Rui Barbosa e sua família entre 1895 e 1923. Os questionários foram respondidos por profissionais de museus-casas e pelo público do Museu Casa de Rui Barbosa. No primeiro caso, o objetivo foi investigar as metodologias de documentação museológica; já com a pesquisa de público, buscamos incluir as demandas e percepções dos visitantes sobre o museu-casa. Após essas reflexões e investigações, foi possível elaborar a metodologia de catalogação dos cômodos, que inclui as etapas de observação e leitura dos compartimentos da casa, análise de suas propriedades e preenchimento da ficha catalográfica. Até o presente momento, a pesquisa demonstrou o possível ineditismo desta metodologia, que tem potencial para ser adaptada à realidade de outros museus-casas.
ABSTRACT This article shows the results of the study “Development of methodology for cataloging the rooms of a historic house museum, understood as museum objects”, developed within the scope of the Incentive Program for the Production of Technical and Scientific Knowledge in the Culture Area of the House of Rui Barbosa Foundation. The study methodology included a literature review and application of questionnaires. Firstly, we discussed the historic house museum category and the relevance of studying domestic interiors in this context; then, we discussed the understanding of the rooms as museum objects and the importance of recording the social trajectory of museological artifacts. In the fourth section of this article, we present and reflect on the collection of object rooms of the Rui Barbosa Historic House, which is located in a construction built in 1850 that served as residence to Rui Barbosa and his family between 1895 and 1923. The field research included questionnaires with professionals of the historic house museum and with the public of the Rui Barbosa Historic House Museum. In the first case, the objective was to investigate the methodologies adopted for elaborating the museum documentation; the research with the public sought to include the visitors’ demands and perceptions regarding the house museum. After such reflections and investigations, elaborating the cataloguing methodology for the rooms was possible, which includes the steps of observation and reading of the house compartments, the analysis of their properties, and the filling of the catalogue records. Up until now, the research has demonstrated the possible novelty of this methodology, which has potential to be adapted to the realities of other historic house museums.
Minas Gerais is the fourth largest Brazilian state, and has an estimate of 354 native fish species. However, these fish species may be threatened, as this state has the highest rank of fish ...introductions reported for Brazil and South America. As one from the total of 85 non-native species detected, Lepomis gibbosus was introduced in the 60s to serve both as foragefish and to improve sport fishing. In this study, we evaluated the establishment of L. gibbosus in a shallow lake in the city ofOuro Preto, Doce River basin, state of Minas Gerais, Southeastern Brazil. We collected fish with fishing rods every two months from March 2002-February 2003. Fragments of gonads from a total of 226 females and 226 males were obtained and processed following standard histological techniques; then 5-7 microm thickness sections were taken and stained in hematoxylin-eosin. Besides, for each specimen, the biometric measurements included the standard length (SL) and body weight (BW); and the sex ratio was obtained. The reproductive cycle stages were confirmed by the distribution of oocytes and spermatogenic cells. The type of spawning was determined by the frequency distribution of the reproductive cycle stages and ovarian histology. Based on the microscopic characteristics of the gonads, the following stages of the reproductive cycle were determined: one=Rest, two=Mature, three=Spawned for females or Spent for males; males and females in reproduction were found throughout the study period. Post-spawned ovaries containing oocytes in stages one (initial perinucleolar), two (advanced perinucleolar), three (pre-vitellogenic), four (vitellogenic) and post-ovulatory follicles indicated fractionated-type spawning in this species. The smallest breeding male and female measured were 4.6 and 4.9cm standard length, respectively, suggesting stunting. The sex ratio did not vary between males and females along the year and bimonthly, being 1:1. Moreover, L. gibbosus appears to be at stage three of biological invasion: establishment through reproduction. We suggest to deliver information about "non-native species" through lectures in schools, colleges/universities, NGOs, government and environmental agencies in the cities and villages, in order to try to prevent environmental degradation by the introduction of non-native fish such as L. gibbosus in the region. We also recommend high fines for red-handed, and the import ban of non-native fish species to the region.
The present study proposes an alternative analytical method for the determination of acrylamide in potato chips, using 2-naphthalenethiol as derivatization reagent followed by a HPLC separation with ...fluorescence detection to be used as a routine analytical procedure in the potato chip industry. The proposed method requires a relatively low-cost instrumentation compared to the mass spectrometry-based methods or other sample cleanup techniques. The optimal conditions for the derivatization process were a reaction temperature of 90 °C, reaction time of 40 min, and a concentration of 7.3 mM of 2-naphthalenethiol. The sample preparation consisted only in an aqueous extraction and a defatting step with hexane. The limit of detection obtained was 129.2 μg kg
−1
. The acrylamide content of nine commercial potato chip samples was found in the interval of 269.21–1405.30 μg kg
−1
.
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