Combined effects of copper, nickel, and zinc on growth of a freshwater mussel (Villosa iris) in an environmentally relevant context

2021 ◽  
pp. 106038
Author(s):  
Anthony J. Timpano ◽  
Jess W. Jones ◽  
Braven Beaty ◽  
Matthew Hull ◽  
David J. Soucek ◽  
...  
Keyword(s):  
Freshwater Mussel ◽  
Combined Effects ◽  
Copper Nickel ◽  
Relevant Context

Effects of Retinoic Acid and 1,25-Dihydroxyvitamin D3 on IFN-gamma Secretion by Mononuclear Leukocytes from Nulliparous and Postparturient Dairy Cattle

2000 ◽  
Vol 70 (3) ◽  
pp. 92-101 ◽  
Author(s):  
Burim Ametaj ◽  
Brian Nonnecke ◽  
Ronald Horst ◽  
Donald Beitz
Keyword(s):  
Retinoic Acid ◽  
Dairy Cattle ◽  
Dairy Cows ◽  
Dairy Cow ◽  
Pokeweed Mitogen ◽  
Mononuclear Leukocytes ◽  
Combined Effects ◽  
Ifn Gamma ◽  
Dihydroxyvitamin D ◽  
1,25 Dihydroxyvitamin D

Individual and combined effects of several isomers of retinoic acid (RA) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on interferon-gamma (IFN-gamma) secretion by blood mononuclear leukocytes (MNL) from nulliparous and postparturient Holstein cattle were evaluated in vitro. In the first experiment, effects on incubation period (24 to 72 hours) and time of supplementation (0 to 32 hours) with all-trans, 9-cis, 13-cis-, and 9,13-dicis-RAs (0 to 100 nM) on IFN-gamma secretion by pokeweed mitogen (PWM)-stimulated (0 and 10 mug/ml) MNL from nulliparous cattle were evaluated. In the second experiment, MNL from postparturient cows (bled at 0, 2, 4, and 16 days postpartum) were stimulated with PWM (0 and 10 mug/ml) in the presence of RA isomers (9-cis- or 9,13-dicis-RA; 0 to 100 nM), 1,25-(OH)2D3 (0 to 100 nM), or with combinations of these metabolites. The results show that individual isomers of RA had no effect on IFN-gamma secretion by PWM-stimulated MNL from nulliparous or postparturient cows. Furthermore 1,25-dihydroxyvitamin D3 inhibited IFN-gamma secretion by MNL from nulliparous and postparturient dairy cows; however, the degree of inhibition was greater when 9-cis- and 9,13-dicis-RA were also present in the cultures. Finally mononuclear leukocytes from postparturient dairy cows produced substantially less IFN-gamma than did MNL from nulliparous cattle. It is concluded that retinoic acids individually did not affect the capacity of leukocytes from dairy cattle to secrete IFN-gamma. This result is in marked contrast to studies in monogastric species indicating that RAs inhibit IFN-gamma secretion by peripheral blood T cells. Inhibition of IFN-gamma secretion by 1,25-(OH)2D3 was potentiated by 9-cis- and 9,13-di-cis-retinoics acids, suggesting that an excess of dietary vitamins A and D may compromise further the naturally immunosuppressed postparturient dairy cow. Additional research is necessary to determine if the combined effects of these metabolites on IFN-gamma secretion represent an increased susceptibility of the dairy cow to infectious diseases during the periparturient period. Lower secretion of IFN-gamma by MNL from postpartutient dairy cows, relative to nulliparous cattle, suggests that recently-calved cows are naturally immunosuppressed.

The Influence of Emotionally Relevant Context on the Evoked Cardiac Response Triggered by an Irrelevant Stimulus

2003 ◽  
Vol 17 (2) ◽  
pp. 61-68 ◽  
Author(s):  
Michal Kuniecki ◽  
Robert Barry ◽  
Jan Kaiser
Keyword(s):  
Task Performance ◽  
Auditory Stimulus ◽  
Irrelevant Stimulus ◽  
Cardiac Response ◽  
Mental Task ◽  
Negative Valence ◽  
Cardiac Deceleration ◽  
Relevant Context ◽  
Stimulus Valence ◽  
Affective Stimulus

Abstract The effect of stimulus valence was examined in the evoked cardiac response (ECR) elicited by the exposition of neutral and negative slides as well as by an innocuous auditory stimulus presented on the affective foregrounds generated by the slides. The exposition of the aversive slide produced prolonged cardiac deceleration in comparison with the neutral slide. Similar prolonged deceleration accompanied exposition of the neutral auditory stimulus on the negative visual foreground in comparison with the neutral foreground. We interpret these results as an autonomic correlate of extended stimulus processing associated with the affective stimulus. The initial deceleration response, covering two or three slower heart beats, may be prolonged for several seconds before HR reaches the baseline level again. In such a case the evoked cardiac deceleration can be functionally divided into two parts: the reflexive bradycardia (ECR1) elicited by neutral stimuli and a late decelerative component (LDC). We can speculate that the latter is associated with an additional voluntary continuation of processing of the stimulus. This must involve some cognitive aspect different from the mental task performance which leads to the accelerative ECR2, and we suggest that processing of a stimulus with negative valence is involved in generating the LDC.

Combined effects of form- and meaning-based predictability on perceived clarity of speech.

2018 ◽  
Vol 44 (2) ◽  
pp. 277-285 ◽  
Author(s):  
Carine Signoret ◽  
Ingrid Johnsrude ◽  
Elisabet Classon ◽  
Mary Rudner
Keyword(s):  
Combined Effects

Combined effects of the prosteatotic TM6SF2 and PNPLA3 variants on severity of NALFD: multicentre biopsy-based study in German patients

2015 ◽  
Vol 53 (12) ◽  
Author(s):  
M Krawczyk ◽  
M Rau ◽  
J Schattenberg ◽  
H Bantel ◽  
A Pathil ◽  
...  
Keyword(s):  
Combined Effects

Freshwater Mussel (Batissa violacea) Fishery and its Value in Fiji

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Jimaima Lako ◽  
Nanise Kuridrani ◽  
Milika Sobey
Keyword(s):  
Value Chain ◽  
Environmental Conditions ◽  
Rural Women ◽  
Freshwater Mussel ◽  
Face To Face

This paper examines the local freshwater mussel, or kai (Batissa violacea), fishery value chain, its values and contribution to the livelihood of people in Viti Levu, Fiji. The assessment was performed through face-to-face interviews, with the use of semi-structured questionnaires administered to 125 actors. A walk through the value-chain was also conducted that confirmed the sites’ environmental conditions. Results revealed that even though the kai fishery is dominated by rural women, men were also employed as kai processors, transporting agents and exporters. This fishery generated at least 58 other employments through the 500 kai harvesters within the five major provinces understudy. These were drivers, boat builders, retailers, processors, exporters, and harvesters. Three sales pathways were identified that determined the revenues and profits: (i) harvesters sell own harvests directly to the consumer at the municipal markets, (ii) harvesters sell through intermediary traders to consumers, and (iii) harvesters sell through processors to supermarkets, hotels or exporters. When revenues and profits were calculated, harvesters earned much less, compared to intermediary traders, processors, and exporters. Major constraints include continuous reduction in catch size of kai, lack of transport, and marketing at the local municipal markets that require improvements.

Mechanisms leading to recruitment inhibition of giant kelp Macrocystis pyrifera by an understory alga

2021 ◽  
Vol 657 ◽  
pp. 59-71
Author(s):  
BA Beckley ◽  
MS Edwards
Keyword(s):  
Field Experiments ◽  
Local Community ◽  
Kelp Forest ◽  
Macrocystis Pyrifera ◽  
Forest Recovery ◽  
Kelp Forests ◽  
Giant Kelp ◽  
Combined Effects ◽  
Life Stages ◽  
Survival And Growth

The forest-forming giant kelp Macrocystis pyrifera and the communities it supports have been decreasing across their native ranges in many parts of the world. The sudden removal of giant kelp canopies by storms increases space and light for the colonization by understory macroalgae, such as Desmarestia herbacea, which can inhibit M. pyrifera recovery and alter local community composition. Understanding the mechanisms by which algae such as D. herbacea interact with M. pyrifera can provide insight into patterns of kelp forest recovery following these disturbances and can aid in predicting future community structure. This study experimentally tested the independent and combined effects of two likely competitive mechanisms by which D. herbacea might inhibit recovery of M. pyrifera in the Point Loma kelp forest in San Diego, California (USA). Specifically, we conducted field experiments to study the individual and combined effects of shade and scour by D. herbacea on the survival of M. pyrifera microscopic life stages, and the recruitment, survival, and growth of its young sporophytes. Our results show that scour had the strongest negative effect on the survival of M. pyrifera microscopic life stages and recruitment, but shade and scour both adversely affected survival and growth of these sporophytes as they grew larger. Canopy-removing storms are increasing in frequency and intensity, and this change could facilitate the rise of understory species, like D. herbacea, which might alter community succession and recovery of kelp forests.

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