Using laboratory incubations to predict the fate of pharmaceuticals in aquatic ecosystems

2018 ◽  
Vol 15 (8) ◽  
pp. 463 ◽  
Author(s):  
Johan Fahlman ◽  
Jerker Fick ◽  
Jan Karlsson ◽  
Micael Jonsson ◽  
Tomas Brodin ◽  
...  

Environmental contextEnvironmental persistence of excreted pharmaceuticals in aquatic ecosystems is usually predicted using small-scale laboratory experiments assumed to simulate natural conditions. We studied five pharmaceuticals comparing their removal rates from water under laboratory conditions and under natural environmental conditions existing in a large pond. We found that the laboratory conditions did not fully capture the complexity within the pond, which led to different removal rates in the two systems. AbstractEnvironmental persistence is a key property when evaluating risks with excreted pharmaceuticals in aquatic ecosystems. Such persistence is typically predicted using small-scale laboratory incubations, but the variation in aquatic environments and scarcity of field studies to verify laboratory-based persistence estimates create uncertainties around the predictive power of these incubations. In this study we: (1) assess the persistence of five pharmaceuticals (diclofenac, diphenhydramine, hydroxyzine, trimethoprim and oxazepam) in laboratory experiments under different environmental conditions; and (2) use a three-month-long field study in an aquatic ecosystem to verify the laboratory-based persistence estimates. In our laboratory assays, we found that water temperature (TEMP), concentrations of organic solutes (TOC), presence of sediment (SED), and solar radiation (SOL) individually affected dissipation rates. Moreover, we identified rarely studied interaction effects between the treatments (i.e. SOL×SED and TEMP×SOL), which affected the persistence of the studied drugs. Half-lives obtained from the laboratory assays largely explained the dissipation rates during the first week of the field study. However, none of the applied models could accurately predict the long-term dissipation rates (month time-scale) from the water column. For example, the studied antibioticum (trimethoprim) and the anti-anxiety drug (oxazepam) remained at detectable levels in the aquatic environment long after (~150 days) our laboratory based models predicted complete dissipation. We conclude that small-scale laboratory incubations seem sufficient to approximate the short-term (i.e. within a week) dissipation rate of drugs in aquatic ecosystems. However, this simplistic approach does not capture interacting environmental processes that preserve a fraction of the dissolved pharmaceuticals for months in natural water bodies.

Author(s):  
S. Papavinasam ◽  
A. Doiron ◽  
T. Panneerselvam ◽  
Y. Lafrenie`re ◽  
M. Attard ◽  
...  

The design of coatings must be adequate to protect pipelines under long-term, severe environmental conditions, including the extreme climatic conditions that will apply in the North before the pipe is installed and operation begins. Practices and standardised methodologies for evaluating and qualifying pipeline coatings for application in northern pipelines are discussed. Results from laboratory and field experiments, carried out under the conditions to which coatings will be exposed during construction, are presented. Based on 1-year laboratory experiments in which samples were exposed to temperatures as low as −45°C and limited data from the field experiments, it is concluded that Canadian Standards Association (CSA) standards CSA Z662, CSA Z245.20 and CSA Z245.21 adequately cover evaluation of coatings for northern pipelines. However, in order to evaluate the effects of low-temperatures, the specimens should be exposed for at least 4 months. Coatings qualified by CSA Z245.21 (System B1 and B2) are less affected from exposure to low-temperatures than those qualified by CSA Z245.21 (System A1) and CSA Z245.20.


2013 ◽  
Vol 164 (2) ◽  
pp. 37-46 ◽  
Author(s):  
Peter Bebi ◽  
Frank Krumm ◽  
Urs-Beat Brändli ◽  
Andreas Zingg

Dynamics of dense, uniform spruce-dominated mountain forests Dense, uniform stands have increased in spruce-dominated mountain forests during the last century and often cause silvicultural problems. During recent years, different research activities at Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) have addressed the development of such mountain forests with or without active management. For this, plots of the Swiss National Forest Inventory (NFI) between 1983/1985 and 2004/2006 have been analysed, dendroecological methods have been used to investigate competition and selfthinning processes and a reassessment of WSL long-term investigation plots has been conducted. NFI plots of stands which have already been dense during the first inventory period generally showed increasing basal area, stagnating stem numbers, strongly increasing amounts of deadwood and slightly increasing regeneration levels, both in managed and in unmanaged stands. Dendroecological field studies confirm that trees in the generally about 80 to 150 years old stands were strongly affected by competition-induced self-thinning and subsequent small-scale mortality processes few decades after stand initiation already. WSL long-term investigation plots generally confirm this dominance of relatively small-scale processes, but also show potential for silvicultural interventions, especially in early stages of self-thinning. According to the guidelines for silvicultural intervention in forests with protective functions (NAIS), an active management of later self-thinning stages with already short crowns and higher mortality should focus on stands where risks have to be considered as too high, based on hazard and damage potential and the size of the dense, uniform stands.


Author(s):  
M. P. Doubrovsky ◽  
I. Yu. Dobrov ◽  
A. V. Gerashchenko ◽  
O. M. Dubrovska

When constructing piled clusters and structures supported by large mono-piles, piles designed are used to take up significant lateral and pressing-in loads. New effective and less resource-demanding design of piled cluster was considered before. At this paper some results of its model testing in laboratory conditions are analyzed and discussed. To increase energy-absorbing capacity of mooring/fender dolphins it was worked out and researched a new design of combined tubular mono-pile structure, incorporating internal flexible pile and damping element placed at the zone of pile head. This design has been tested by laboratory experiments using small scale model. Obtained results confirm its effectiveness and practicability.


2019 ◽  
Vol 105 (6) ◽  
pp. 1078-1085
Author(s):  
Catherine Marquis-Favre

Noise annoyance models using only mean energy-based indices provide weak prediction. Actually various factors influence noise annoyance. different studies from the literature are carried out in laboratory conditions to understand some factors with the long-term aim of enhancing noise annoyance models. Laboratory experiments of assessing noise annoyance are based on imaginary or simulated context. The method with imaginary context is often questioned as participants listen to noise sequences. The current study aims at comparing the two methods in terms of total annoyance model testing. It revealed that annoyance models, respectively built within imaginary and simulated contexts, provided similar prediction when they were tested using in-field annoyance responses. Thus, the laboratory method with imaginary context seems to be as suitable as the method with simulated context to assess annoyance in laboratory conditions.


2012 ◽  
Vol 279 (1749) ◽  
pp. 5048-5057 ◽  
Author(s):  
Fyodor A. Kondrashov

A subject of extensive study in evolutionary theory has been the issue of how neutral, redundant copies can be maintained in the genome for long periods of time. Concurrently, examples of adaptive gene duplications to various environmental conditions in different species have been described. At this point, it is too early to tell whether or not a substantial fraction of gene copies have initially achieved fixation by positive selection for increased dosage. Nevertheless, enough examples have accumulated in the literature that such a possibility should be considered. Here, I review the recent examples of adaptive gene duplications and make an attempt to draw generalizations on what types of genes may be particularly prone to be selected for under certain environmental conditions. The identification of copy-number variation in ecological field studies of species adapting to stressful or novel environmental conditions may improve our understanding of gene duplications as a mechanism of adaptation and its relevance to the long-term persistence of gene duplications.


2015 ◽  
Vol 2015 ◽  
pp. 1-22 ◽  
Author(s):  
S. Riehl ◽  
E. Asouti ◽  
D. Karakaya ◽  
B. M. Starkovich ◽  
M. Zeidi ◽  
...  

The evidence for the slow development from gathering and cultivation of wild species to the use of domesticates in the Near East, deriving from a number of Epipalaeolithic and aceramic Neolithic sites with short occupational stratigraphies, cannot explain the reasons for the protracted development of agriculture in the Fertile Crescent. The botanical and faunal remains from the long stratigraphic sequence of Chogha Golan, indicate local changes in environmental conditions and subsistence practices that characterize a site-specific pathway into emerging agriculture. Our multidisciplinary approach demonstrates a long-term subsistence strategy of several hundred years on wild cereals and pulses as well as on hunting a variety of faunal species that were based on relatively favorable and stable environmental conditions. Fluctuations in the availability of resources after around 10.200 cal BP may have been caused by small-scale climatic fluctuations. The temporary depletion of resources was managed through a shift to other species which required minor technological changes to make these resources accessible and by intensification of barley cultivation which approached its domestication. After roughly 200 years, emmer domestication is apparent, accompanied by higher contribution of cattle in the diet, suggesting long-term intensification of resource management.


2003 ◽  
Vol 93 (5) ◽  
pp. 413-423 ◽  
Author(s):  
T.A. Evans

AbstractThe exploration of sand-filled arenas by workers of an entire colony of the Australian, subterranean foraging, tree-nesting termite, Coptotermes frenchi Hill was investigated under laboratory conditions. The first experiment tested whether termite exploration of sand was influenced by the presence of gaps or objects in the sand. Gaps and objects were chosen to represent soil heterogeneity in the urban environment: gaps to represent tunnels dug by other animals, perspex strips to represent cables and pipes, and wood strips to represent roots. Termites always chose to explore gaps thoroughly before they began tunnelling in the sand. Significantly more and longer tunnels were excavated from the end of gaps at the far end of the arenas, and relatively little tunnelling occurred around and along objects. Termite density was significantly greater around and along wood compared with perspex blocks. The second experiment tested whether termite exploratory tunnelling was influenced by soil moisture. The termites tunnelled slowly in dry sand, but after discovering a patch of wet sand, increased tunnelling five-fold until it was completely explored, after which activity declined. Energy and water conservation may be behind these patterns of exploratory tunnelling as well as those seen in large field studies, but caution is urged when interpreting small scale laboratory experiments to explain large scale field data.


1983 ◽  
Vol 61 (6) ◽  
pp. 1401-1404 ◽  
Author(s):  
Lucius Stebbins ◽  
David Daisley

A reliable and simple device suitable for long-term recording of activity in natural environmental conditions is described. It is inexpensive to make, assembled with standard electronic components, and adaptable for a wide range of animal sizes. Instructions for assembly which can be interpreted with a minimum of electronics knowledge and parts lists with catalog numbers for a common Canadian electronics retailer are provided.


Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.


2021 ◽  
pp. 095679762097751
Author(s):  
Li Zhao ◽  
Jiaxin Zheng ◽  
Haiying Mao ◽  
Xinyi Yu ◽  
Jiacheng Ye ◽  
...  

Morality-based interventions designed to promote academic integrity are being used by educational institutions around the world. Although many such approaches have a strong theoretical foundation and are supported by laboratory-based evidence, they often have not been subjected to rigorous empirical evaluation in real-world contexts. In a naturalistic field study ( N = 296), we evaluated a recent research-inspired classroom innovation in which students are told, just prior to taking an unproctored exam, that they are trusted to act with integrity. Four university classes were assigned to a proctored exam or one of three types of unproctored exam. Students who took unproctored exams cheated significantly more, which suggests that it may be premature to implement this approach in college classrooms. These findings point to the importance of conducting ecologically valid and well-controlled field studies that translate psychological theory into practice when introducing large-scale educational reforms.


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