Long-term effects of the antibacterial agent triclosan on marine periphyton communities

Triclosan (TCS) is a widely used antibacterial agent that has become a ubiquitous contaminant in freshwater, estuary and marine environments. Concerns for potential adverse effects of TCS have been described in several recent risk assessments. Effects on freshwater microbial communities have been quite well studied but studies addressing effects on marine microbial communities are scarce. Here we describe short- and long-term effects of TCS on marine periphyton (microbial biofilm) communities. Short-term effects on photosynthesis were estimated after 60 – 210 minutes exposure. Long-term effects on photosynthesis, chlorophyll fluorescence, pigment content, community tolerance and bacterial carbon utilization were studied after exposing periphyton for 17 days in flow-through microcosms to 0.316 - 10 000 nM TCS. Results from the short-term studies show that TCS is toxic to periphyton photosynthesis. EC50 values of 1080 and 3000 nM were estimated using 14CO2-incorporation and Pulse Amplitude Modulation (PAM), respectively. After long-term TCS exposure in flow-through microcosms photosynthesis estimated using PAM was, however, not inhibited by TCS concentrations up to 1000 nM, but instead increased with increasing TCS concentration. Similarly, the amount of photosynthetic pigments increased after an exposure of 31.6 nM TCS and higher; at 316 nM TCS the pigment amounts reached between 140 and 190% of the control level. Pollution-Induced Community Tolerance (PICT) was observed for algae and cyanobacteria at 100 nM TCS and higher. In spite of the widespread use of TCS as an antibacterial agent, the compound did not have any effects on bacterial carbon utilization after long-term exposure.

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Validity of an Ecotoxicological Test System: Short-Term and Long-Term Effects of Arsenate on Marine Periphyton Communities in Laboratory Systems

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f88-212 ◽

1988 ◽

Vol 45 (10) ◽

pp. 1807-1815 ◽

Cited By ~ 51

Author(s):

Hans Blanck ◽

Sten-Åke Wängberg

Keyword(s):

Relevant Information ◽

Test System ◽

Physiological Parameter ◽

Long Term Effects ◽

Short Term ◽

Ecotoxicological Test ◽

Arsenate Stress ◽

Flow Through ◽

Chlorophyll A Content

Periphyton communities were established on glass substratum in the Gullmar Fjord (Sweden) and their sensitivity to arsenate was determined with short-term photosynthesis experiments. The study was done in May 1984 when phosphate levels were low. A 1-h exposure to arsenate gave IC20 (concentration required to inhibit photosynthesis by 20%) values of 0.4 μM. Communities established indoors in a flow-through aquaria system were substantially different from the fjord communities in terms of structure and biomass, although photosynthesis showed a similar sensitivity (IC20 = 0.6 μM). To explore the validity of this short-term ecotoxicological test system, we used a set of indoor, flow-through aquaria to study long-term effects (3 wk) on communities established under arsenate stress. Arsenate was added continuously at 0.1–10 μM above background levels (7 nM). Species composition as well as carbon, nitrogen, and chlorophyll a content of the communities were affected at 0.2–0.8 μM (IC20). This is in good agreement with the sensitivity of the short-term test. We conclude that inhibition of the physiological parameter photosynthesis is relevant information for the understanding of ecological events caused by arsenate stress in the periphyton communities. At least for effects of arsenate, the short-term metabolic test system can be used for valid predictions of gross changes in periphyton community structure and production. Comparison with arsenic levels in polluted coastal areas of Sweden lead to the conclusion that periphyton communities may be affected, particularly when phosphorus levels are low.

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Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159412 ◽

1990 ◽

Vol 48 (3) ◽

pp. 374-375

Author(s):

D.E. Loudy ◽

J. Sprinkle-Cavallo ◽

J.T. Yarrington ◽

F.Y. Thompson ◽

J.P. Gibson

Keyword(s):

Antidepressant Drug ◽

Beagle Dogs ◽

Long Term Effects ◽

Short Term ◽

Platelet Counts ◽

Toxicological Studies ◽

Induced Aggregation ◽

Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

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SUMBER-SUMBER RESILIENSI PADA REMAJA AKHIR YANG MENGALAMI KEKERASAN DARI ORANGTUA PADA MASA KANAK-KANAK

Psibernetika ◽

10.30813/psibernetika.v11i1.1161 ◽

2018 ◽

Vol 11 (1) ◽

Author(s):

Devina Calista ◽

Garvin Garvin

Keyword(s):

Late Adolescents ◽

Long Term Effects ◽

Short Term ◽

Parental Affection ◽

Resilience Factors ◽

Childhood Violence ◽

Past Experiences ◽

The Impact ◽

Depth Interviews

Child abuse by parents is common in households. The impact of violence on children will bring short-term effects and long-term effects that can be attributed to their various emotional, behavioral and social problems in the future; especially in late adolescence that will enter adulthood. Resilience factors increase the likelihood that adolescents who are victims of childhood violence recover from their past experiences, become more powerful individuals and have a better life. The purpose of this study was to determine the source of resilience in late adolescents who experienced violence from parents in their childhood. This research uses qualitative research methods with in-depth interviews as a method of data collection. The result shows that the three research participants have the aspects of "I Have", "I Am", and "I Can"; a participant has "I Can" aspects as a source of resilience, and one other subject has no source of resilience. The study concluded that parental affection and acceptance of the past experience have role to the three sources of resilience (I Have, I Am, and I Can) Keyword : Resilience, adolescence, violence, parents

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The Long-Term Effects of Short-Term Populist Law Reforms: Evidence from Argentina

SSRN Electronic Journal ◽

10.2139/ssrn.3573803 ◽

2020 ◽

Author(s):

Maximiliano Marzetti ◽

Rok Spruk

Keyword(s):

Long Term Effects ◽

Short Term

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Feasibility and Enjoyment of Exercise Video Games in Older Adults

Innovation in Aging ◽

10.1093/geroni/igaa057.1838 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 559-559

Author(s):

Sara Freed ◽

Briana Sprague ◽

Lesley Ross

Keyword(s):

Older Adults ◽

Video Games ◽

Game Design ◽

Long Term Effects ◽

Short Term ◽

Qualitative And Quantitative ◽

Before And After ◽

Xbox Kinect ◽

Game Developers

Abstract Interventions using exercise video games, or exergames, have shown short-term cognitive and physical benefits to older adults, though long-term effects are less promising. Enjoyment of exergames may promote exergame use after the intervention period, though little work has examined older adults’ views of exergames before and after gameplay experience. We invited 20 older adults between 65 and 84 years of age (M=73.30, SD=5.95) to play two Xbox Kinect games, Just Dance and Kinect Sports Rivals, for twenty minutes. In our presentation, we will present qualitative and quantitative findings of this pilot study, including findings that older adults reported that they were not likely to play similar exergames in the future and that they did not find the exergames to be more fun compared to other ways of exercising. We will discuss implications for game design and research relevant to game developers, manufacturers, and researchers. Part of a symposium sponsored by Technology and Aging Interest Group.

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Electrical stimulation of referred sensation area alleviates phantom limb pain

Restorative Neurology and Neuroscience ◽

10.3233/rnn-201132 ◽

2021 ◽

pp. 1-10

Author(s):

Michihiro Osumi ◽

Daisuke Shimizu ◽

Yuki Nishi ◽

Shu Morioka

Keyword(s):

Electrical Stimulation ◽

Single Case ◽

Phantom Limb Pain ◽

Phantom Limb ◽

Long Term Effects ◽

Limb Pain ◽

Short Term ◽

Analgesic Effects ◽

Stimulation Of

Background: Patients with brachial plexus avulsion (BPA) usually experience phantom sensations and phantom limb pain (PLP) in the deafferented limb. It has been suggested that evoking the sensation of touch in the deafferented limb by stimulating referred sensation areas (RSAs) on the cheek or shoulder might alleviate PLP. However, feasible rehabilitation techniques using this approach have not been reported. Objective: The present study sought to examine the analgesic effects of simple electrical stimulation of RSAs in BPA patients with PLP. Methods: Study 1: Electrical stimulation of RSAs for 60 minutes was conducted for six BPA patients suffering from PLP to examine short-term analgesic effects. Study 2: A single case design experiment was conducted with two BPA patients to investigate whether electrical stimulation of RSAs was more effective for alleviating PLP than control electrical stimulation (electrical stimulation of sites on side opposite to the RSAs), and to elucidate the long-term effects of electrical stimulation of RSAs. Results: Study 1: Electrical stimulation of RSAs evoked phantom touch sensations in the deafferented limb, and significantly alleviated PLP (p < 0.05). Study 2: PLP was alleviated more after electrical stimulation on RSAs compared with control electrical stimulation (p < 0.05). However, the analgesic effects of electrical stimulation on RSAs were observed only in the short term, not in the long term (p > 0.05). Conclusions: Electrical stimulation of RSAs not only evoked phantom touch sensation but also alleviated PLP in the short term. The results indicate that electrical stimulation of RSAs may provide a useful practical rehabilitation technique for PLP. Future studies will be required to clarify the mechanisms underlying immediate PLP alleviation via electrical stimulation of RSAs.

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A medium-scale volume dielectric barrier discharge system for short-term treatment of cereal seeds indicates improved germination performance with long-term effects

Journal of Applied Physics ◽

10.1063/5.0033369 ◽

2021 ◽

Vol 129 (4) ◽

pp. 044904

Author(s):

H. Brust ◽

T. M. C. Nishime ◽

N. Wannicke ◽

T. S. M. Mui ◽

S. Horn ◽

...

Keyword(s):

Dielectric Barrier Discharge ◽

Barrier Discharge ◽

Term Treatment ◽

Long Term Effects ◽

Short Term ◽

Short Term Treatment ◽

Discharge System ◽

Dielectric Barrier ◽

Medium Scale

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Long-Term Development of Urban Agriculture: Resilience and Sustainability of Farmers Facing the Covid-19 Pandemic in Japan

Sustainability ◽

10.3390/su13084316 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4316

Author(s):

Shingo Yoshida ◽

Hironori Yagi

Keyword(s):

Urban Agriculture ◽

Food Systems ◽

Direct Marketing ◽

Farming System ◽

Long Term Effects ◽

Short Term ◽

Short Supply ◽

Using Data ◽

Urban People

The coronavirus disease 2019 (Covid-19) pandemic has forced global food systems to face unprecedented uncertain shocks even in terms of human health. Urban agriculture is expected to be more resilient because of its short supply chain for urban people and diversified farming activities. However, the short-and long-term effects of the Covid-19 pandemic on urban farms remain unclear. This study aims to reveal the conditions for farm resilience to the Covid-19 pandemic in 2020 and the relationship between short-term farm resilience and long-term farm development using data from a survey of 74 farms located in Tokyo. The results are as follows. First, more than half of the sample farms increased their farm sales during this period. This resilience can be called the “persistence” approach. Second, short-term farm resilience and other sustainable farm activities contributed to improving farmers’ intentions for long-term farm development and farmland preservation. Third, the most important resilience attributes were the direct marketing, entrepreneurship, and social networks of farmers. We discussed the necessity of building farmers’ transformative capabilities for a more resilient urban farming system. These results imply that support to enhance the short-term resilience of urban farms is worth more than the short-term profit of the farms.

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