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You searched for subject:(energetic stressors). Showing records 1 – 2 of 2 total matches.

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Louisiana State University

1. Jones, Hollis. Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica.

Degree: MS, Marine Biology, 2018, Louisiana State University

Crassostrea virginica, the eastern oyster, forms reefs that provide critical services and benefits to the resiliency of the surrounding ecosystem. Changes in environmental conditions, including salinity and temperature, can dramatically alter the services oysters provide by affecting their population dynamics. Climate warming may further exacerbate the effects of salinity changes as precipitation events increase in frequency, intensity, and duration. Temperature and salinity independently and synergistically influence gene expression and physiology in marine organisms. We used comparative transcriptomics, physiology, and a field assessment experiment to investigate whether Louisianan oyster are changing their phenotypes to cope with increased temperature and salinity stress in Gulf of Mexico. Oysters from Sister Lake, Louisiana were exposed to fully crossed temperature (20°C and 30°C) and salinity (25ppt, 15ppt, and 7ppt) treatments. We found a higher number of genes were differentially expressed (downregulated) in response to low salinity at warmer temperatures – suggesting metabolic suppression. Gene ontology terms for ion transport and microtubule based processes were significantly enriched among upregulated genes in response to low salinity. Ion transport plays a role in osmolyte regulation which is important to maintain cell volume during low salinity. Microtubule based processes play a role in ciliary action which can improve fluid transport, prolonging aerobic metabolism and survival at low salinities. Oyster respiration rate significantly increased between 20°C and 30°C but, despite the higher energetic demands the clearance rate did not comparably increase. To investigate transcriptional differences in wild populations, we collected tissue from three locations across the Louisiana Gulf. We determined the expression levels of seven target genes and found an upregulation of genes that function in osmolyte transport, oxidative stress mediation, apoptosis, and protein synthesis at our low salinity site and sampling time point. Overall, oysters altered their phenotype more in response to low salinity at higher temperatures as evidenced by a higher number of differentially expressed genes during laboratory exposure, increased respiration (higher energetic demands), differentially expression by season and location. Warm temperatures lower the eastern oyster’s ability to cope with low salinities; the timing and length of low salinity exposure is important for understanding oyster recruitment, mortality, and growth.

Subjects/Keywords: Crassostrea virginica; multiple stressors; energetic tradeoffs; climate change; transcriptome

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Jones, H. (2018). Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica. (Masters Thesis). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_theses/4819

Chicago Manual of Style (16th Edition):

Jones, Hollis. “Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica.” 2018. Masters Thesis, Louisiana State University. Accessed April 15, 2021. https://digitalcommons.lsu.edu/gradschool_theses/4819.

MLA Handbook (7th Edition):

Jones, Hollis. “Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica.” 2018. Web. 15 Apr 2021.

Vancouver:

Jones H. Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica. [Internet] [Masters thesis]. Louisiana State University; 2018. [cited 2021 Apr 15]. Available from: https://digitalcommons.lsu.edu/gradschool_theses/4819.

Council of Science Editors:

Jones H. Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica. [Masters Thesis]. Louisiana State University; 2018. Available from: https://digitalcommons.lsu.edu/gradschool_theses/4819


University of Illinois – Urbana-Champaign

2. Rogers, Mary Patricia. Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors.

Degree: PhD, Anthropology, 2018, University of Illinois – Urbana-Champaign

Reproductive ecology has long examined the flexibility of women’s reproductive function in the face of variable environments. The timing of a woman’s first menses, or age at menarche, is both used as a proxy of childhood stressors and correlated with adolescent and adult reproductive function. This research seeks to understand the connections between childhood environments, pubertal timing, and adult reproductive function, and I specifically 1) identify a need for including social support measures in studies of pubertal timing through empirical evidence that positive parental-child interactions affect age at menarche, 2) demonstrate that psychosocial and energetic stressors experienced during childhood correlate with pubertal timing and adult reproductive function, 3) compare timing of menarche and variation in reproductive hormones between two populations with similar geographic origins but different subsistence environments, and 4) investigate gene methylation as a potential mechanism mediating the relationship between key stressors and reproductive function. I first investigated relationships between parent-adolescent communication and age at menarche in a diverse sample of 128 post-menarcheal, American girls aged 12-17. I found that measures of close family relationships, specifically open communication with parents, were correlated with age at menarche in this sample. I further found that mother-adolescent and father-adolescent open communication scores had opposing directional effects on menarcheal timing. These findings suggest that maternal and paternal communication may signal different things about the developmental and reproductive environment. This research underscores the importance of including measures of family support in future studies of adolescent reproductive trait timing, as well as the consideration that positive psychosocial factors, rather than only negative psychosocial factors, may be associated with accelerated menarcheal development. I further investigated the secular trend of declining ages at menarche in in the rural Beskid Wyspowy region of southern Poland and investigated relationships between childhood stressors, age at menarche, and adult reproductive function. I found that age at menarche has declined over time in rural Poland. Helping on farms and with farm animals as a child were associated with later ages at menarche. Women with a higher number of adverse childhood experiences tended to have earlier age at menarche, although this difference was not statistically significant. Despite different effects on age at menarche, all types of childhood stressors were associated with lower adult E1G concentrations. The results of this study support a model under which developmental conditions affect adult reproductive function, but challenge the use of age at menarche alone as a proxy for childhood stressors. I compared differences in reproductive traits between women in rural Poland and Polish American women in urban areas of the United States. We found that ages at menarche are… Advisors/Committee Members: Clancy, Kathryn B.H. (advisor), Malhi, Ripan S. (advisor), Clancy, Kathryn B.H. (Committee Chair), Malhi, Ripan S. (Committee Chair), Roseman, Charles (committee member), Uddin, Monica (committee member).

Subjects/Keywords: age at menarche; reproductive ecology; gene methylation; epigenetics; reproductive function; energetic stressors; psychosocial stressors; estradiol; progesterone

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Rogers, M. P. (2018). Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/101759

Chicago Manual of Style (16th Edition):

Rogers, Mary Patricia. “Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed April 15, 2021. http://hdl.handle.net/2142/101759.

MLA Handbook (7th Edition):

Rogers, Mary Patricia. “Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors.” 2018. Web. 15 Apr 2021.

Vancouver:

Rogers MP. Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2142/101759.

Council of Science Editors:

Rogers MP. Variation in age at menarche and adult reproductive function: the role of energetic and psychosocial stressors. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/101759

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