scholarly journals Sensitivity towards elevated <i>p</i>CO<sub>2</sub> in great scallop (<i>Pecten maximus</i> Lamarck) embryos and fed larvae

2017 ◽  
Vol 14 (3) ◽  
pp. 529-539 ◽  
Author(s):  
Sissel Andersen ◽  
Ellen S. Grefsrud ◽  
Torstein Harboe
Keyword(s):  
Shell Growth ◽  
Elevated Pco2 ◽  
Pecten Maximus ◽  
Early Life Stages ◽  
Negative Effects ◽  
Ph Values ◽  
Great Scallop ◽  
Negative Effect ◽  
Seawater Carbonate Chemistry

Abstract. The increasing amount of dissolved anthropogenic CO2 has caused a drop in pH values in the open ocean known as ocean acidification. This change in seawater carbonate chemistry has been shown to have a negative effect on a number of marine organisms. Early life stages are the most vulnerable, and especially the organisms that produce calcified structures in the phylum Mollusca. Few studies have looked at effects on scallops, and this is the first study presented including fed larvae of the great scallop (Pecten maximus) followed until day 14 post-fertilization. Fertilized eggs from unexposed parents were exposed to three levels of pCO2 using four replicate units: 465 (ambient), 768 and 1294 µatm, corresponding to pHNIST of 7.94, 7.75 (−0.19 units) and 7.54 (−0.40 units), respectively. All of the observed parameters were negatively affected by elevated pCO2: survival, larval development, shell growth and normal shell development. The latter was observed to be affected only 2 days after fertilization. Negative effects on the fed larvae at day 7 were similar to what was shown earlier for unfed P. maximus larvae. Growth rate in the group at 768 µatm seemed to decline after day 7, indicating that the ability to overcome the environmental change at moderately elevated pCO2 was lost over time. The present study shows that food availability does not decrease the sensitivity to elevated pCO2 in P. maximus larvae. Unless genetic adaptation and acclimatization counteract the negative effects of long term elevated pCO2, recruitment in populations of P. maximus will most likely be negatively affected by the projected drop of 0.06–0.32 units in pH within year 2100.

scholarly journals Sensitivity towards elevated <i>p</i>CO<sub>2</sub> in great scallop (<i>Pecten maximus</i> Lamarck) embryos and fed larvae

2016 ◽  
Author(s):  
Sissel Andersen ◽  
Ellen S. Grefsrud ◽  
Torstein Harboe
Keyword(s):  
Ocean Acidification ◽  
Shell Growth ◽  
Elevated Pco2 ◽  
Pecten Maximus ◽  
Negative Effects ◽  
Great Scallop ◽  
Scallop Larvae ◽  
Negative Effect ◽  
Seawater Carbonate Chemistry

Abstract. The increasing amount of dissolved anthropogenic CO2 has caused a drop in pH-values in the open ocean known as ocean acidification. This change in seawater carbonate chemistry has been shown to have a negative effect on a number of marine organisms. Early life stages are the most vulnerable, and especially the organisms that produce calcified structures in the phylum Mollusca. Few studies have looked at effects on scallops, and this is the first study presented including fed larvae of the great scallop (Pecten maximus) followed until day 14 post-fertilization. Fertilized eggs from unexposed parents were exposed to three levels of pCO2 using four replicate units: 465 (ambient), 768 and 1294 μatm, corresponding to pHNBS of 7.94, 7.74 and 7.54, respectively. All of the observed parameters were negatively affected by elevated pCO2: survival, larval development, shell growth and normal shell development. The latter was observed to be affected only two days after fertilization. Negative effects on the fed larvae at day 7 were similar to what was shown earlier for unfed P. maximus larvae. Growth rate in the group at 768 μatm seemed to decline after day 7, indicating that the ability to overcome the environmental change at moderately elevated pCO2 was lost over time. Food availability may not decrease the sensitivity to elevated pCO2 in scallop larvae. Unless genetic adaptation and acclimatization counteract the negative effects of long term elevated pCO2, populations of scallops may be negatively affected by ocean acidification in the future.

scholarly journals Effect of increased <i>p</i>CO<sub>2</sub> level on early shell development in great scallop (<i>Pecten maximus</i> Lamarck) larvae

2013 ◽  
Vol 10 (10) ◽  
pp. 6161-6184 ◽  
Author(s):  
S. Andersen ◽  
E. S. Grefsrud ◽  
T. Harboe
Keyword(s):  
Marine Invertebrates ◽  
Shell Growth ◽  
Elevated Pco2 ◽  
Pecten Maximus ◽  
Long Term Effects ◽  
Negative Effects ◽  
Pco2 Level ◽  
Larval Stages ◽  
Great Scallop ◽  
Veliger Larvae

Abstract. As a result of high anthropogenic CO2 emissions, the concentration of CO2 in the oceans has increased, causing a decrease in pH, known as ocean acidification (OA). Numerous studies have shown negative effects on marine invertebrates, and also that the early life stages are the most sensitive to OA. We studied the effects of OA on embryos and unfed larvae of the great scallop (Pecten maximus Lamarck), at pCO2 levels of 469 (ambient), 807, 1164, and 1599 μatm until seven days after fertilization. To our knowledge, this is the first study on OA effects on larvae of this species. A drop in pCO2 level the first 12 h was observed in the elevated pCO2 groups due to a discontinuation in water flow to avoid escape of embryos. When the flow was restarted, pCO2 level stabilized and was significantly different between all groups. OA affected both survival and shell growth negatively after seven days. Survival was reduced from 45% in the ambient group to 12% in the highest pCO2 group. Shell length and height were reduced by 8 and 15%, respectively, when pCO2 increased from ambient to 1599 μatm. Development of normal hinges was negatively affected by elevated pCO2 levels in both trochophore larvae after two days and veliger larvae after seven days. After seven days, deformities in the shell hinge were more connected to elevated pCO2 levels than deformities in the shell edge. Embryos stained with calcein showed fluorescence in the newly formed shell area, indicating calcification of the shell at the early trochophore stage between one and two days after fertilization. Our results show that P. maximus embryos and early larvae may be negatively affected by elevated pCO2 levels within the range of what is projected towards year 2250, although the initial drop in pCO2 level may have overestimated the effect of the highest pCO2 levels. Future work should focus on long-term effects on this species from hatching, throughout the larval stages, and further into the juvenile and adult stages.

scholarly journals Effect of increased <i>p</i>CO<sub>2</sub> on early shell development in great scallop (<i>Pecten maximus</i> Lamarck) larvae

2013 ◽  
Vol 10 (2) ◽  
pp. 3281-3310 ◽  
Author(s):  
S. Andersen ◽  
E. S. Grefsrud ◽  
T. Harboe
Keyword(s):  
Marine Invertebrates ◽  
Shell Growth ◽  
Elevated Pco2 ◽  
Pecten Maximus ◽  
Negative Effects ◽  
Co2 Partial Pressure ◽  
Great Scallop ◽  
Egg Number ◽  
Veliger Larvae ◽  
Trochophore Stage

Abstract. As a result of high anthropogenic emission of CO2, partial pressure of carbon dioxide (pCO2) in the oceans has increased causing a drop in pH, known as ocean acidification (OA). Numerous studies have shown negative effects on marine invertebrates, and that the early life stages are the most sensitive to OA. We studied the effects on embryo and larvae of great scallop (Pecten maximus L.), using mean pCO2-levels of 477 (ambient), 821, 1184, and 1627 ppm. OA affected both survival and shell growth negatively after seven days. Growth was reduced with 5–10% when pCO2 increased from ambient 477 ppm to 1627 ppm, and survival based on egg number was reduced from 40.4% in the ambient group to 10.7% in the highest pCO2-group. Larvae/embryos stained with calcein one day after fertilization, showed fluorescence in the newly formed shell area indicating calcification of the shell already at the trochophore stage. Shell hinge deformities were observed at elevated pCO2-levels in trochophore larvae after two days. After seven days, deformities in both shell hinge and shell edge were observed in veliger larvae at elevated pCO2-levels. Although the growth showed a moderate reduction, survival rate and increased amount of deformed larvae indicates that P. Maximus larvae are affected by elevated pCO2 levels within the range of what is projected for the next century.

scholarly journals Long-term subjective memory after electroconvulsive therapy

BJPsych Open ◽  
2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Robert Sigström ◽  
Axel Nordenskjöld ◽  
Anders Juréus ◽  
Caitlin Clements ◽  
Erik Joas ◽  
...  
Keyword(s):  
Electroconvulsive Therapy ◽  
Memory Impairment ◽  
Rating Scale ◽  
Final Analysis ◽  
Negative Effects ◽  
Subjective Memory ◽  
Subjective Memory Impairment ◽  
Negative Effect ◽  
Negative Expectations

Background There have been reports of long-term subjective memory worsening after electroconvulsive therapy (ECT). Aims To study the prevalence and risk factors of long-term subjective memory worsening among patients receiving ECT in routine clinical practice. Method Patients (n = 535, of whom 277 were included in the final analysis) were recruited from eight Swedish hospitals. Participants' subjective memory impairment was assessed before ECT and a median of 73 days after ECT using the memory item from the Comprehensive Psychopathological Rating Scale. Participants also rated their pre-ECT expectations and post-ECT evaluations of the effect of ECT on memory on a 7-point scale. We used ordinal regression to identify variables associated with subjective memory worsening and negative evaluations of the effect of ECT on memory. Results Comparisons of pre- and post-ECT assessments showed that subjective memory worsened in 16.2% of participants, remained unchanged in 52.3% and improved in 31.4%. By contrast, when asked to evaluate the effect of ECT on memory after treatment 54.6% reported a negative effect. Subjective memory worsening was associated with negative expectations before ECT, younger age and shorter duration of follow-up. Conclusions Although subjective memory improved more often than it worsened when assessed before and after ECT, a majority of patients reported that ECT had negative effects on their memory when retrospectively asked how ECT had affected it. This might suggest that some patients attribute pre-existing subjective memory impairment to ECT. Clinicians should be aware that negative expectations are associated with subjective worsening of memory after ECT.

scholarly journals High frequency Barium profiles in shells of the Great Scallop <i>Pecten maximus</i>: a methodical long-term and multi-site survey in Western Europe

2008 ◽  
Vol 5 (5) ◽  
pp. 3665-3698 ◽  
Author(s):  
A. Barats ◽  
D. Amouroux ◽  
L. Chauvaud ◽  
C. Pécheyran ◽  
A. Lorrain ◽  
...  
Keyword(s):  
High Frequency ◽  
Western Europe ◽  
Pecten Maximus ◽  
Coastal Environments ◽  
Great Scallop ◽  
Site Survey ◽  
Scallop Shells ◽  
Bay Of Brest ◽  
Long Term Survey

Abstract. Skeletal barium/calcium ([Ba]/[Ca])shell ratios were measured every third daily striae in 39 flat valves of the Great Scallop Pecten maximus (2-year old; 3 shells/year) collected in temperate coastal environments of Western Europe. Variations of ([Ba]/[Ca])shell ratio were first demonstrated reproducible for several scallop individuals from the same population, over a 7-year period (1998–2004), and from different coastal environments in France (42–49° N). As in previous studies, ([Ba]/[Ca])shell profiles exhibited a background ratio punctuated by transient maxima occurring in summer. Background partition coefficient (DBa=0.11±0.03, in 2000) was similar to that previously reported in P. maximus shells (DBa=0.18), suggesting a direct shell uptake of dissolved seawater Ba (Gillikin et al., 2008). Special attention was then dedicated to the complete monitoring of high resolution ([Ba]/[Ca])shell profiles in bivalve shells (7 years, Bay of Brest) to better constrain environmental processes influencing both the occurrence and the amplitude of summer peaks. In 2000, seawater Ba analyses underlined significant particulate Ba inputs at the seawater interface (SWI) during ([Ba]/[Ca])shell peak events. These Ba inputs are suggested to be subsequent to and rather induced by a pelagic biogenic process. The long term survey revealed first that archived Ba within the shell cannot be used as a direct paleo productivity tracer, and second that complex pelagic/benthic processes in the Ba cycle are responsible of particulate Ba inputs to the SWI, subsequently taken up by the bivalve and recorded as higher ([Ba]/[Ca])shell ratios. When these processes will be better constrained, high frequency observations of Ba in scallop shells would provide new insights into filter feeding dynamics and into Ba biogeochemistry in coastal environments.

No long-term effect of intracoelomic acoustic transmitter implantation on survival, growth, and body condition of a long-lived stenotherm in the wild

2020 ◽  
Author(s):  
Justin A. G. Hubbard ◽  
Brendan E. Hickie ◽  
Jeff Bowman ◽  
Lee E. Hrenchuk ◽  
Paul J. Blanchfield ◽  
...  
Keyword(s):  
Body Condition ◽  
Lake Trout ◽  
Negative Effects ◽  
Term Survival ◽  
Acoustic Transmitter ◽  
Negative Effect ◽  
In The Wild ◽  
Surgical Implantation ◽  
Fish Survival

A fundamental assumption of biotelemetry studies is that there are no adverse consequences from the surgical implantation or presence of the acoustic transmitter. In fisheries, most studies have evaluated this assumption over only short time periods (<2 y) in a laboratory setting. Here we compared the survival, growth, and body condition of populations of Lake Trout (Salvelinus namaycush) in three lakes containing tagged and untagged individuals over a 12-year period (2002-2013). We found no significant negative effects of acoustic telemetry tagging on the long-term survival of fish (estimates of combined annual survival ranged from 67% to 91%), and no negative effect of surgical implantation on growth or body condition for fish of either sex. Additionally, we found no significant effect of transmitter:fish mass ratio on fish survival, growth (with the exception of smaller-bodied fish in one lake), or condition. All implanted fish received tags weighing <1.25% of their mass (in water), indicating that this criterion is desirable for larger-bodied adult Lake Trout. Our findings support the assumption that long-lived fish species tagged with acoustic transmitters via intracoelomic surgery survive, grow, and maintain body condition similar to un-tagged conspecifics over the long-term in the wild.

Protective Nature of Platelet-Rich Plasma Against Chondrocyte Death When Combined With Corticosteroids or Local Anesthetics

2016 ◽  
Vol 45 (1) ◽  
pp. 218-225 ◽  
Author(s):  
Thomas J.S. Durant ◽  
Corey R. Dwyer ◽  
Mary Beth R. McCarthy ◽  
Mark P. Cote ◽  
James P. Bradley ◽  
...  
Keyword(s):  
Local Anesthetics ◽  
Platelet Rich Plasma ◽  
Symptomatic Relief ◽  
Negative Effects ◽  
Chondrocyte Proliferation ◽  
Cytotoxic Effects ◽  
Chondrocyte Viability ◽  
Chondrocyte Death ◽  
Negative Effect

Background: The use of corticosteroids and local anesthetics to treat osteoarthritis has established benefits, including relief of pain and increased range of motion, but may also have the potential to lead to tissue atrophy or degeneration, specifically on chondrocytes. There is growing evidence that platelet-rich plasma (PRP) has anti-inflammatory characteristics that can limit the cytotoxic effects of corticosteroids and local anesthetics. Hypothesis/Purpose: The purpose of this study was to determine the effects of PRP in chondrocyte cultures when combined with corticosteroids or local anesthetics. The hypothesis of this study was that PRP would (1) dampen the negative effects on chondrocyte viability and (2) improve chondrocyte proliferation seen with corticosteroid or local anesthetic treatment alone. Study Design: Controlled laboratory study. Methods: Peripheral blood was obtained from 8 healthy participants, followed by centrifugation to obtain PRP. Human chondrocytes were treated with PRP alone or in combination with corticosteroids or local anesthetics. Saline (concentration of 0.9%) served as the control. Luminescence and radioactive thymidine assays were performed to examine chondrocyte viability and proliferation, respectively. Cell exposures of 0, 5, 10, and 30 minutes were used for viability and 120 hours for proliferation. Results: The presence of PRP significantly limited the negative effect on chondrocyte viability at tested time points for the examined corticosteroids and local anesthetics ( P < .05). PRP in addition to corticosteroids and local anesthetics significantly improved chondrocyte proliferation ( P < .05). Conclusion: The addition of PRP can significantly reduce the cytotoxic effects of corticosteroids and/or local anesthetics applied to chondrocytes. PRP can improve the proliferation of chondrocytes compared with corticosteroids or local anesthetics alone. Clinical Relevance: With the use of corticosteroids and local anesthetics for temporary symptomatic relief and improvement of function to treat the chronic progressive nature of osteoarthritis, long-term negative effects of these agents can be limited with the parallel use of PRP.

Attributes of long-term heavy cannabis users: a case–control study

2003 ◽  
Vol 33 (8) ◽  
pp. 1415-1422 ◽  
Author(s):  
A. J. GRUBER ◽  
H. G. POPE ◽  
J. I. HUDSON ◽  
D. YURGELUN-TODD
Keyword(s):  
Social Life ◽  
Subjective Effects ◽  
The United States ◽  
Case Control ◽  
Self Report ◽  
Negative Effects ◽  
Heavy Users ◽  
Confounding Variables ◽  
Negative Effect

Background. Although cannabis is the most widely used illicit drug in the United States, few recent American studies have examined the attributes of long-term heavy cannabis users.Method. Using a case–control design, we obtained psychological and demographic measures on 108 individuals, age 30–55, who had smoked cannabis a mean of 18000 times and a minimum of 5000 times in their lives. We compared these heavy users to 72 age-matched control subjects who had smoked at least once, but no more than 50 times in their lives.Results. We found no significant differences between the two groups on reported levels of income and education in their families of origin. However, the heavy users themselves reported significantly lower educational attainment (P<0·001) and income (P=0·003) than the controls, even after adjustment for a large number of potentially confounding variables. When asked to rate the subjective effects of cannabis on their cognition, memory, career, social life, physical health and mental health, large majorities of heavy users (66–90%) reported a ‘negative effect’. On several measures of quality of life, heavy users also reported significantly lower levels of satisfaction than controls.Conclusion. Both objective and self-report measures suggest numerous negative features associated with long-term heavy cannabis use. Thus, it seems important to understand why heavy users continue to smoke regularly for years, despite acknowledging these negative effects. Such an understanding may guide the development of strategies to treat cannabis dependence.

scholarly journals Customer Experience Management: Underexplored Instrument for Customer Transformation

2021 ◽  
Vol 15 (37) ◽  
Author(s):  
David Havíř
Keyword(s):  
Theory Development ◽  
Well Being ◽  
Customer Experience ◽  
Negative Effects ◽  
Digital Products ◽  
Customer Experience Management ◽  
Negative Effect ◽  
Perception Gap ◽  
Development Approach

Purpose of the article: The purpose of this article is to identify the role the customer experience plays in the transformation of the customer and to develop a theory that brings together related concepts in order to position the phenomenon of customer experience in the macromarketing context.Methodology/methods: The grounded theory development approach is based upon the sequential search and content analysis of the research papers acquired primarily from Scopus and Web of Science databases and by the process of citation chaining.Scientific aim: The aim of this article is to identify customer experience related concepts and relationships between them to lay the foundation for empirical research in the area of customer experience and transformation management.Findings: The research points out to the significant role of the customer experience in the transformation of the customer and therefore to the necessity to approach marketing initiatives to customer experience management thoroughly to achieve the desired marketing results, but also responsibly and ethically to promote growth not the degradation of the society.Conclusions: The cycle of the customer transformation as outlined through the conceptual model contains weak spots which can provide free space for negative effects of the company’s outputs on the customer. The trend of digitisation and digital products can significantly amplify this possibility and increase the overall negative effect. From another standpoint, several problematic spots can cause difficulties for companies intentionally trying to transform the customer through their outputs, namely intent-result gap, reality-perception gap, single-part gap, and experience-memory gap.Scientific research in this area might support the effectiveness of marketing initiatives, increase transparency in the field of customer experience and transformation, and lead to increased customers’ well-being, long-term happiness, life satisfaction, and quality of life.

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