Search results for "Life stage"
showing 10 items of 32 documents
Effects of bioheapleaching technology utilizing metal mine emissions on fish in boreal freshwaters
2018
Emissions from metal mining activities are known to deteriorate the quality of aquatic habitats and impair the condition and reproductive potential of fish. Metal extraction by biomining methods has been considered to cause fewer emissions, but for example in Finland, the impacts of a bioheapleaching technology utilizing metal mine on the local freshwaters have been substantial. In this thesis, the impacts of the bioheapleaching mine emissions on three native fish species, brown trout (Salmo trutta) European perch (Perca fluviatilis) and whitefish (Coregonus lavaretus pallasi), were investigated. Manganese and sulphate concentrations have been elevated in the mining impacted waters, and in …
Estado de salud en adolescentes de España, México y Chile durante la COVID-19: un estudio transcultural.
2021
espanolLa pandemia provocada por la COVID-19 es una crisis sin precedentes en la historia reciente, cuyas consecuencias han tenido un impacto mundial. Una de las etapas mas vulnerables a los efectos de esta emergencia sanitaria es la adolescencia, pues atraviesan un proceso vital de cambios en diversos aspectos de su vida, y la inestabilidad social y economica se suma como factor de riesgo a su ajuste psicosocial. Los estudios a nivel transcultural han tratado de comparar y comprender las diferencias en la adaptacion de los y las adolescentes a la pandemia en diferentes partes del mundo. El objetivo de este estudio fue analizar el estado de salud actual, en comparacion con el estado de salu…
Recent Changes in Student Life and Study ProcessesABSTRACT
1995
This research on university and university students was carried out during the 1980s at the University of Jyvaskyla in Finland. It is argued that the student years no longer constitute a ‘classically’ academic life stage; instead, the modem student's life is divided between study and part‐time employment. The uncertain economic situation and social immaturity of today's students hampers their identity formation. Student culture has lost its independence and vitality, and the basic structures of students’ life‐world have fragmented so that their lives no longer revolve around the university. Moreover, curricularization in universities has instrumentalized the study process and the relation o…
Effect of substrate particle size on burrowing of the juvenile freshwater pearl mussel Margaritifera margaritifera
2021
AbstractJuveniles of the endangered freshwater pearl mussel (FPM,Margaritifera margaritifera) live burrowed in stream substrate for the first years of their life. Fine sediments block water exchange within substrate and may cause juvenile mortality and recruitment failure. To better understand the connection between success of juvenile FPM and substrate particle size, it would be important to understand behavioural responses of FPM to varying substrate sizes at this critical life stage. We placed newly detached FPM juveniles in a 7-mm layer of sieved sand sorted into five sizes (< 120, 120–200, 200–250, 250–500 and 500–650 µm) each with 10 replicate dishes, 10 juveniles per dish, with bu…
Conservation, Spillover and Gene Flow within a Network of Northern European Marine Protected Areas
2013
Published version of an article in the journal: PLoS ONE. Also available from the publisher at: http://dx.doi.org/10.1371/journal.pone.0073388 Open access To ensure that marine protected areas (MPAs) benefit conservation and fisheries, the effectiveness of MPA designs has to be evaluated in field studies. Using an interdisciplinary approach, we empirically assessed the design of a network of northern MPAs where fishing for European lobster (Homarus gammarus) is prohibited. First, we demonstrate a high level of residency and survival (50%) for almost a year (363 days) within MPAs, despite small MPA sizes (0.5-1 km2). Second, we demonstrate limited export (4.7%) of lobsters tagged within MPAs…
Evolutionary constraints of warning signals : a genetic trade-off between the efficacy of larval and adult warning coloration can maintain variation …
2016
To predict evolutionary responses of warning signals under selection, we need to determine the inheritance pattern of the signals, and how they are genetically correlated with other traits contributing to fitness. Furthermore, protective coloration often undergoes remarkable changes within an individual's lifecycle, requiring us to quantify the genetic constraints of adaptive coloration across all the relevant life stages. Based on a 12 generation pedigree with > 11,000 individuals of the wood tiger moth (Arctia plantaginis), we show that high primary defense as a larva (large warning signal) results in weaker defenses as adult (less efficient warning color), due to the negative genetic cor…
Evaluating responses to temperature during pre-metamorphosis and carry-over effects at post-metamorphosis in the wood tiger moth (Arctia plantaginis)
2019
Insect metamorphosis is one of the most recognized processes delimiting transitions between phenotypes. It has been traditionally postulated as an adaptive process decoupling traits between life stages, allowing evolutionary independence of pre- and post-metamorphic phenotypes. However, the degree of autonomy between these life stages varies depending on the species and has not been studied in detail over multiple traits simultaneously. Here, we reared full-sib larvae of the warningly coloured wood tiger moth ( Arctia plantaginis ) in different temperatures and examined their responses for phenotypic (melanization change, number of moults), gene expression (RNA-seq and qPCR of candidate ge…
In situ behavior of wild long-snouted seahorse Hippocampus guttulatus Cuvier, 1829
2021
The study of behavior is one of the fundamental aspects of conservation biology. While for animals such as mammals there are well-defined protocols that have been applied for a long time, for marine animals, and fish in particular, studies are available for a limited number of species. The behavior of seahorses, for example, is poorly studied and in this work, we made a first attempt of using video recordings to analyze behavior of these endangered species in Mar Piccolo of Taranto (Southern Italy). The study presents preliminary data on behavioral activities and their comparisons among different life stages of Hippocampus guttulatus, namely females, males, and juveniles. Juveniles and fema…
Use of Early Juvenile Zebrafish Danio Rerio for In-Vivo Assessment of Endocrine Modulation by Xenoestrogens
2013
Reliable and cost-effective early-life stage (ELS) bioassays incorporating practical experimentation without compromising scientific relevance are crucial in chemical risk assessment. This study investigated the use of 20 days- post-fertilization life stage ( 20dpfZF ) of zebrafish Danio rerio to screen environmental chemicals known to be estrogenic in adult fish. Firstly, studies with key genes in steroidogenesis were conducted; the brain isoform of aromatase gene ( cyp19a1b ) being the most prominently expressed biomarker. Regulation of mRNA levels of molecular biomarkers, vitellogenin 1 gene ( vtg1) and cyp19a1b were selected to assess the endocrine modulation by xenoestrogens, 17α-ethin…
Antipredator strategies of pupae: how to avoid predation in an immobile life stage?
2019
Antipredator strategies of the pupal stage in insects have received little attention in comparison to larval or adult stages. This is despite the fact that predation risk can be high during the pupal stage, making it a critical stage for subsequent fitness. The immobile pupae are not, however, defenceless; a wide range of antipredator strategies have evolved against invertebrate and vertebrate predators. The most common strategy seems to be ‘avoiding encounters with predators' by actively hiding in vegetation and soil or via cryptic coloration and masquerade. Pupae have also evolved behavioural and secondary defences such as defensive toxins, physical defences or deimatic movements and soun…