RESUMO
The public has expressed growing concern for the well-being of fishes, including popular pet species such as the Siamese fighting fish (Betta splendens). In captivity, male Bettas behave aggressively, often causing injuries and death if housed together. As a result, they are typically isolated in small fishbowls, which has been widely criticised as cruel. To investigate the impact of keeping Bettas in these conditions, we recorded the behaviour of individual males in containers of different sizes that were either bare or enriched with gravel, large rocks, and live plants. When male Bettas were housed individually in small bowls (0.5 L) they spent less time swimming than they did when they were kept in larger aquaria (10, 38, and 208 L). Fish that were kept in enriched containers exhibited more instances of swimming. To determine if two male Bettas housed together might coexist peacefully if given enough space and cover from plants and large rocks, we quantified the behaviour of pairs of male Bettas in bare or enriched aquaria of different sizes (10, 38, 208, 378 L). Fish performed fewer approaches and aggressive displays, but not attacks, and more bouts of foraging, when in larger aquaria. This study shows that the small fishbowls typically used in pet stores suppress swimming behaviour in male Bettas and at least a 10-L aquarium is required to ensure full expression of swimming behaviour. Furthermore, even the use of very large aquaria cannot guarantee peaceful cohabitation between two males.
RESUMO
Perennial shrub willow are increasingly being promoted in short-rotation coppice systems as biomass feedstocks, for phytoremediation applications, and for the diverse ecosystem services that can accrue. This renewed interest has led to widespread willow cultivation, particularly of non-native varieties. However, Canadian willow species have not been widely adopted and their inherent diversity has not yet been thoroughly investigated. In this study, 324 genotypes of Salix famelica and Salix eriocephala collected from 33 sites of origin were analyzed using 26,016 single nucleotide polymorphisms to reveal patterns of population structure and genetic diversity. Analyses by Bayesian methods and principal component analysis detected five main clusters that appeared to be largely shaped by geoclimatic variables including mean annual precipitation and the number of frost-free days. The overall observed (HO) and expected (HE) heterozygosity were 0.126 and 0.179, respectively. An analysis of molecular variance revealed that the highest genetic variation occurred within genotypes (69%), while 8% of the variation existed among clusters and 23% between genotypes within clusters. These findings provide new insights into the extent of genetic variation that exists within native shrub willow species which could be leveraged in pan-Canadian willow breeding programs.
Assuntos
Salix , Teorema de Bayes , Canadá , Ecossistema , Variação Genética , Melhoramento Vegetal , Salix/genéticaRESUMO
Cell wall recalcitrance is a major constraint for the exploitation of lignocellulosic biomass as a renewable resource for energy and bio-based products. Transcriptional regulators of the lignin biosynthetic pathway represent promising targets for tailoring lignin content and composition in plant secondary cell walls. However, knowledge about the transcriptional regulation of lignin biosynthesis in lignocellulosic feedstocks, such as Miscanthus, is limited. In Miscanthus leaves, MsSCM1 and MsMYB103 are expressed at growth stages associated with lignification. The ectopic expression of MsSCM1 and MsMYB103 in N. benthamiana leaves was sufficient to trigger secondary cell wall deposition with distinct sugar and lignin compositions. Moreover, RNA-seq analysis revealed that the transcriptional responses to MsSCM1 and MsMYB103 overexpression showed an extensive overlap with the response to the NAC master transcription factor MsSND1, but were distinct from each other, underscoring the inherent complexity of secondary cell wall formation. Furthermore, conserved and previously described promoter elements as well as novel and specific motifs could be identified from the target genes of the three transcription factors. Together, MsSCM1 and MsMYB103 represent interesting targets for manipulations of lignin content and composition in Miscanthus towards a tailored biomass.
Assuntos
Lignina/biossíntese , Proteínas de Plantas/metabolismo , Poaceae/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo , Biomassa , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Poaceae/genética , Poaceae/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , RNA-Seq/métodos , Fatores de Transcrição/genética , Transcriptoma/genéticaRESUMO
Intraoperative cranial nerve neuromonitoring (IONM) has significantly reduced morbidity historically associated with skull-base procedures. It provides the surgeon with immediate feedback to preserve both anatomic and physiologic function of monitored nerves. However, when the surgeon cauterizes tissue near the nerve, the monitoring equipment is saturated by the cautery signal, eliminating IONM information at a critical time. The use of an infrared camera under the drapes to observe the face for movement due to nerve stimulation is an invaluable adjunct to traditional IONM. Monitoring may also be improved by contralateral electrode placement to help identify artifact from nerve stimulation, using the microscope's video output to compare the surgeon's hand movements to recorded activity, and learning basic anatomy of the inner ear and skull base in order to know when heightened attention is important.