9 research outputs found
Reproduction and stress response endocrinology in blue (Balaenoptera musculus) and gray (Eschrichtius robustus) whales
Thesis (Ph.D.) University of Alaska Fairbanks, 2020Identification of biomarkers that reflect physiological status is fundamental for assessing population health, as well as providing more accurate estimates of life history parameters. Blue (Balaenoptera musculus) and gray (Eschrichtius robustus) whale populations feed on lower trophic levels and migrate between the eastern Tropical and the eastern North Pacific Ocean. With increasing disturbances (e.g., changing environment and human activities), understanding the stress response, resultant coping mechanisms, and the subsequent effects on reproduction, is of growing importance. While extensive knowledge is available on photo-identification and ecology of these two species, information on physiology is limited and what exists is outdated. This dissertation validated and measured a suite of steroid hormones in blubber tissue using an enzyme immunoassay technique to develop physiological biomarkers for reproduction and metabolism in these two species. Coupled with sighting history data, progesterone and testosterone were validated as biomarkers for reproductive physiology. In both species, progesterone concentrations were higher in pregnant females and mixture models were developed to estimate reproductive status for whales of unknown status. Testosterone showed greater variability in adult males and concentrations were higher in samples collected during fall, suggesting physiological preparation for mating. Additionally, progesterone concentrations in gray whales were higher in calves of both sexes, indicating maternal transfer through lactation, while in blue whales, testosterone was detectable only in males and in pregnant whales, suggesting its biosynthesis or metabolism is altered during gestation. Biomarkers for stress response were developed through analytical and biological validation of three corticosteroid hormones: cortisol, corticosterone and aldosterone. First, analytical validations (i.e., parallelism and accuracy tests) were used to determine detectability and measurement accuracy of these hormones using commercially available kits. Hormone concentrations were tested for any relationships with life history parameters (e.g., age and reproductive state) as well as with area and time of sampling within presumably "healthy" (biopsies) whales and "stressed" (stranded) whales. "Stressed" whales, especially those that perished due to trauma and/or nutritional stress, had higher concentrations of all three corticosteroid hormones than "healthy" whales, suggesting ongoing alteration of metabolic status due to a stress response. In female "healthy" whales, reproductive status appeared to be a major factor influencing corticosterone concentrations in blue whales and for cortisol in gray whales. Overall, cortisol was determined to be a valid marker for body conditions in both species. These results set a milestone for assisting to better understand the impact of a changing environment on the physiology of these species and can be used to develop more accurate reproductive and survival rates to use in population dynamics models for management of subsistence resources and for conservation of endangered species.Fulbright Scholarship, Alaska IDeA Network of Biomedical Research Excellence (INBRE) Graduate Research Award, University of Alaska Fairbanks (UAF), Calvin-Lensink Fellowship, and the UAF Graduate School Dissertation completion award, INBRE, Biomaedical Learning and students training (BLaST), Society of Marine Mammalogy, Bill Samara Research Award, the Goering Family Scholarship, Cascadia Research CollectiveGeneral introduction -- Chapter 1: Blubber endocrine profiles provide insights on reproductive biology in blue whales from the eastern North Pacific Ocean -- Chapter 2: The use of endocrine biomarkers to update information on gray whale reproductive physiology -- Chapter 3: Corticosteroid hormones as biomarkers for stress response in blubber of blue and gray whales -- General conclusion -- References: General introduction and conclusion
Guidebook 'How to develop a Sustainable Energy and Climate Action Plan (SECAP)'
The Covenant of Mayors for Climate and Energy (CoM) is an ambitious initiative for local climate and energy actions. This document provides signatories with a set of methodological principle, procedures and best practices to develop their SECAP. The Part 1 of this document relates to the SECAP process; while Part 2gives an insight on the elaboration of municipality assessments (BEI and RVA), finally Part 3 describes technical issues, measures and policies that can be implemented at local level.JRC.C.2-Energy Efficiency and Renewable
Density-dependent effects control the reproductive strategy and population growth of Aurelia aurita s.l. scyphistomae
Aureliaaurita s.l. scyphistomae are capable of developing different asexual modes for propagation and thus present a multi-mode reproductive strategy. The reproduction rates and the reproductive strategy they adopt depend on a combination of various environmental parameters. We investigated the A.aurita s.l. polyp-to-polyp reproduction strategy and population growth in relation to polyp density. Our results confirmed that density-dependent factors control population growth of A. aurita s.l. scyphistomae in three different ways: (1) decreasing the polyp reproduction rate, (2) triggering the production of motile bud-like tissue particles and (3) inducing the detachment of developed scyphistomae. Whereas the decrease in the reproduction rate reduces the number of recruits, the motile particles and the detachment of scyphistomae contribute to minimizing density-dependent effects by allowing reproductive products and scyphistomae to drift away. Thus, not only are the negative effects of intraspecific competition for space and food diminished but also the potential colonization of new substrates, and further increase in scyphistoma density is favoured on larger spatial scales. The potential capability to switch its polyp-to-polyp reproduction strategy in response to environmental clues and population density may give Aurelia high adaptability in the temperate coastal waters where they commonly live and where they may be exposed to wide-ranging and fluctuating environmental variables that affect their survival and longevity. Considering these features, as well as the wide tolerance of Aurelia scyphistomae (and medusae) to environmental parameters, it is not surprising that the species/lineages of Aurelia are cosmopolitan and exhibit the most frequent bloom events worldwide.Fil: Schiariti, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Melica, Valentina. University of Trieste; ItaliaFil: Kogovsek, Tjasa. Marine Biology Station Piran; Eslovenia. Hiroshima University; JapónFil: Malej, Alenka. Marine Biology Station Piran; Esloveni
Are European cities achieving emission reduction commitments? A comparative analysis under the Covenant of Mayors initiative
Cities are widely recognized as responsible for Greenhouse Gas emissions while being affected by climate change. The potential of cities in contributing to the climate challenge has been clearly recognized and supported within Europe by the Covenant of Mayors initiative. Climate strategies at the local level are site-specific and suit local communities and territories’ needs and peculiarities. In addition, several drivers can influence the impacts of CC mitigation policies at the urban scale. This paper follows the pathway set by former studies with the aim to understand potential factors positively or negatively influencing the results of planned measures by CoM signatories in their SEAPs by mainly focusing on policy instruments and sectors, in addition to other previously explored characteristics. To this aim, this study provides a regression analysis based on data regarding Baseline Emission Inventories and Monitoring Emission Inventories from a sample of CoM signatories as of August 2019
Group discussions on how to implement a participatory process in climate adaptation planning: a case study in Malaysia
Correction to: Tocilizumab for patients with COVID-19 pneumonia. The single-arm TOCIVID-19 prospective trial
Effect of Tocilizumab vs Usual Care in Adults Hospitalized With COVID-19 and Moderate or Severe Pneumonia
International audienceImportance Severe pneumonia with hyperinflammation and elevated interleukin-6 is a common presentation of coronavirus disease 2019 (COVID-19).Objective To determine whether tocilizumab (TCZ) improves outcomes of patients hospitalized with moderate-to-severe COVID-19 pneumonia.Design, Setting, and Particpants This cohort-embedded, investigator-initiated, multicenter, open-label, bayesian randomized clinical trial investigating patients with COVID-19 and moderate or severe pneumonia requiring at least 3 L/min of oxygen but without ventilation or admission to the intensive care unit was conducted between March 31, 2020, to April 18, 2020, with follow-up through 28 days. Patients were recruited from 9 university hospitals in France. Analyses were performed on an intention-to-treat basis with no correction for multiplicity for secondary outcomes.Interventions Patients were randomly assigned to receive TCZ, 8 mg/kg, intravenously plus usual care on day 1 and on day 3 if clinically indicated (TCZ group) or to receive usual care alone (UC group). Usual care included antibiotic agents, antiviral agents, corticosteroids, vasopressor support, and anticoagulants.Main Outcomes and Measures Primary outcomes were scores higher than 5 on the World Health Organization 10-point Clinical Progression Scale (WHO-CPS) on day 4 and survival without need of ventilation (including noninvasive ventilation) at day 14. Secondary outcomes were clinical status assessed with the WHO-CPS scores at day 7 and day 14, overall survival, time to discharge, time to oxygen supply independency, biological factors such as C-reactive protein level, and adverse events.Results Of 131 patients, 64 patients were randomly assigned to the TCZ group and 67 to UC group; 1 patient in the TCZ group withdrew consent and was not included in the analysis. Of the 130 patients, 42 were women (32%), and median (interquartile range) age was 64 (57.1-74.3) years. In the TCZ group, 12 patients had a WHO-CPS score greater than 5 at day 4 vs 19 in the UC group (median posterior absolute risk difference [ARD] −9.0%; 90% credible interval [CrI], −21.0 to 3.1), with a posterior probability of negative ARD of 89.0% not achieving the 95% predefined efficacy threshold. At day 14, 12% (95% CI −28% to 4%) fewer patients needed noninvasive ventilation (NIV) or mechanical ventilation (MV) or died in the TCZ group than in the UC group (24% vs 36%, median posterior hazard ratio [HR] 0.58; 90% CrI, 0.33-1.00), with a posterior probability of HR less than 1 of 95.0%, achieving the predefined efficacy threshold. The HR for MV or death was 0.58 (90% CrI, 0.30 to 1.09). At day 28, 7 patients had died in the TCZ group and 8 in the UC group (adjusted HR, 0.92; 95% CI 0.33-2.53). Serious adverse events occurred in 20 (32%) patients in the TCZ group and 29 (43%) in the UC group (P = .21).Conclusions and Relevance In this randomized clinical trial of patients with COVID-19 and pneumonia requiring oxygen support but not admitted to the intensive care unit, TCZ did not reduce WHO-CPS scores lower than 5 at day 4 but might have reduced the risk of NIV, MV, or death by day 14. No difference on day 28 mortality was found. Further studies are necessary for confirming these preliminary results.Trial Registration ClinicalTrials.gov Identifier: NCT0433180