Search results for "RATES"
showing 10 items of 1636 documents
The Riverine Organism Drift Imager: A new technology to study organism drift in rivers and streams
2023
1. Drift or downstream dispersal is a fundamental process in the life cycle of many riverine organisms. In the face of rapidly declining freshwater biodiversity, there is a need to enhance our capacity to study the drift of riverine organisms, by overcoming the limitations of traditional labour-intensive sampling methods that result in data of low temporal and spatial resolution. 2. To address this need, we developed a new technology, the Riverine Organism Drift Imager (RODI), which combines in situ imaging with machine-learning classification. This technique expands on the traditional methodology by replacing the collection cup of a drift net with a camera system that continuously images r…
Sulfate sensitivity of aquatic organism in soft freshwaters explored by toxicity tests and species sensitivity distribution
2023
Elevated concentrations of sulfate in waterways are observed due to various anthropogenic activities. Elevated levels of sulfate can have harmful effects on aquatic life in freshwaters: sulfate can cause osmotic stress or specific ion toxicity in aquatic organisms, especially in soft waters where Ca2+ and Mg2+ concentrations are low. Formerly, chronic toxicity test data in soft water have been scarce. The chronic and acute sulfate toxicity tests conducted with aquatic organisms from 10 families across various trophic levels in this study multiplied the number of tests conducted in soft freshwater conditions and enabled derivation of the species sensitivity distribution (SSD) and sulfate haz…
Flotsam samples can help explain the δ13C and δ15N values of invertebrate resting stages in lake sediment
2018
Abstract The stable isotopic composition of chitinous remains of Cladocera (water fleas) and freshwater Bryozoa (moss animals) preserved in lake sediment records can provide supporting insights into past environmental and ecosystem changes in lakes. Here we explore whether analyses of these remains isolated from lake flotsam can provide information on the driving variables affecting the isotopic composition of these remains. We collected flotsam in 53 lakes and found enough material in 33 lakes to measure the stable carbon and nitrogen isotope ratios (expressed as δ13C and δ15N values, respectively) of resting stages. These values were compared with lake characteristics, water chemistry mea…
Anti-inflammatory activity in selected Antarctic benthic organisms
2014
Antarctic benthos was prospected in search for anti-inflammatory activity in polar benthic invertebrates, in two different geographical areas: deep-bottoms of the Eastern Weddell Sea and shallow-waters of the South Shetland Islands. A total of 36 benthic algae and invertebrate species were selected to perform solubility tests in order to obtain extracts that were soluble at an innocuous ethanol concentration (0.2%) for cell culture, and further test them for anti-inflammatory activity. From these, ethanol extracts of ten species from five different phyla resulted suitable to be studied in cell macrophage cultures (RAW 264.7). Cytotoxicity (MTT method) and production of inflammatory mediator…
Development of antibiotic loaded biodegradable matrices to prevent superficial infections associated to total knee arthroplasty.
2019
Abstract Development of a pharmaceutical form for the superficial infections related with arthroplasties would be helpful for clinical practice. In this context, we set out to evaluate ciprofloxacin and gentamicin elution from systems based on chitosan. Films and semisolid hydrogels containing chitosan alone (2%) or in combination with gelatin (6%) or different proportions (from 12% to 36%) of tetrakis-(hydroxymethyl)-phosphonium-chloride (THPC) were tested as delivery systems. Different antibiotic doses were assayed (0.5 mg/cm2,1 mg/cm2 and 2 mg/cm2). Antibiotic release was studied for each formulation. In vitro cytocompatibility studies and a simulation exercise for bioactivity evaluation…
Detecting Asset Misappropriation: Forensic Accounting
2021
The main task of the investigation of asset misappropriation is the correct classification of a crime: identification of the fact of misappropriation and determination of the amount of misappropriated assets. Specificity of asset diversity, asset accounting requirements, and a wide range of misappropriation opportunities require specialised knowledge in accounting and economics that investigators often lack. The aim of the study is to increase the knowledge of investigators in forensic accounting in order to increase effectiveness of investigations in detecting asset misappropriation. In this article, the authors, Latvian and Lithuanian accounting experts, talk about typologies of asset mis…
Fluid escape structures in the north Sicily continental margin
2014
Abstract High resolution and multichannel seismic profiles coupled with multibeam echosounder (seafloor relief) data, acquired along the northern Sicily continental margin (southern Tyrrhenian Sea), document the occurrence of mound and pockmark features, revealing fluid escape processes. Along this margin, morphology of the high-gradient continental slope is irregular due to the presence of structural highs, slope failures and canyons, and is interrupted by flat areas at a mean depth of 1500 m. Seismostratigraphic analysis tools and methods were used to identify fluid escape structures and to work out a classification on the basis of their morpho-acoustic characteristics. The detailed 3D ba…
Studi preliminari sulla propagazione gamica e vegetativa di Hypericum perforatum in ambiente mediterraneo
2014
La conoscenza dei fattori che influenzano la propagazione di una specie rappresenta un passo cruciale nella messa a punto di strategie per la sua moltiplicazione di massa e introduzione in coltura, sia in campo che in ambiente controllato. Sono stati approfonditi alcuni aspetti della propagazione gamica di Hypericum perforatum (di cui è nota la bassa germinabilità del seme), verificando in particolare gli effetti di variabili diverse (soddisfacimento delle esigenze in freddo, temperatura, substrato, presenza di PGPR, batteri promotori della crescita). Sono stati inoltre approfonditi gli studi sulle potenzialità di moltiplicazione vegetativa della specie, da proporre come possibile alternati…
The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in na…
2007
13 pages; International audience; Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the in…
International Student Migration in Finland
2021
There is increasing attention on the retention of international students with many stakeholders desiring to keep international students for long-term economic growth. This study examines the factors affecting international students to stay in Finland five years after initial enrolment with particular focus on the role graduation plays in students staying or leaving. Tracking 11 (years) entering cohorts for five years across national (Finland) data registries, we found evidence of an inverse relationship between graduation, degree type, and the probability of staying; higher the degree level of graduation, the decrease in probability an international student stays. We conclude that while gra…