Search results for "Thermal"
showing 10 items of 3576 documents
Heat hardening capacity in Drosophila melanogaster is life stage-specific and juveniles show the highest plasticity
2019
Variations in stress resistance and adaptive plastic responses during ontogeny have rarely been addressed, despite the possibility that differences between life stages can affect species' range margins and thermal tolerance. Here, we assessed the thermal sensitivity and hardening capacity of Drosophila melanogaster across developmental stages from larval to the adult stage. We observed strong differences between life stages in heat resistance, with adults being most heat resistant followed by puparia , pupae and larvae . The impact of heat hardening (1 h at 35°C) on heat resistance changed during ontogeny, with the highest positive effect of hardening observed in puparia and pupae and the …
Adaptation to climate change of the French wine industry: a systemic approach – Main outcomes of the project LACCAVE
2018
Présenté au 12. Congreso Internacional Terroir; Taking into account the major economical role and specificities of the French wine industry, adaptation to climate change is a very challenging issue. In 2011, 23 research teams launched a systemic and multidisciplinary program to analyze the impacts from the vine to the region, to define adaptation strategies combining technical, spatial and organizational options and to evaluate the perception by the actors and consumers of climate change issues. Thermal variability was studied at local scale to develop high resolution atmospheric models which better simulate future climate trends. Impacts on growth/developmental conditions and vine response…
Influence of warming temperatures on coregonine embryogenesis within and among species
2021
The greatest response of lakes to climate change has been the increase in water temperatures on a global scale. The responses of many lake fishes to warming water temperatures are projected to be inadequate to counter the speed and magnitude of climate change, leaving some species vulnerable to decline and extinction. We experimentally evaluated the responses of embryos from a group of cold, stenothermic fishes (Salmonidae Coregoninae) - within conspecifics across lake systems, between congeners within the same lake system, and among congeners across lake systems - to a thermal gradient using an incubation method that enabled global comparisons. Study groups included cisco (Coregonus artedi…
Allee effect in a manipulative parasite within poikilothermic host under temperature change
2022
AbstractTemperature and intraspecific competition are important factors influencing the growth of all organisms, including parasites. The temperature increase is suggested to stimulate the development of parasites within poikilothermic hosts. However, at high parasite densities, this effect could be diminished, due to stronger intraspecific competition. Our study, for the first time, addressed the joint effects of warming and parasite abundances on parasite growth in poikilothermic hosts. The growth of the common fish parasite larvae (trematode Diplostomum pseudospathaceum) within the rainbow trout at different infection intensities and temperatures (15°C and 18°C) was experimentally invest…
Biorefinery process for hydrothermal liquefaction of microalgae powered by a concentrating solar plant: A conceptual study
2017
Abstract A conceptual analysis of coupling a concentrating solar power plant with a biorefinery process consisting in the hydrothermal liquefaction (HTL) of microalgae to biocrude was performed. The configuration of the CSP-HTL plant was designed to allow continuous operation considering 10 kT of microalgae processed each year using, for the first time, a ternary nitrate mixture as heat transfer fluid and storage medium in the temperature range of 340–410 °C. With adopted models, the capital and operating costs of the solar plant marginally affect the minimum fuel selling prize (MFSP) of biocrude that decreases with the size of the solar field and of the thermal storage system provided that…
Long-term performance and life cycle assessment of energy piles in three different climatic conditions
2020
Abstract The main purpose behind the use of energy piles is to enable the exploitation of geothermal energy for meeting the heating/cooling demands of buildings in an efficient and environment-friendly manner. However, the long-term performance of energy piles in different climatic conditions, along with their actual environmental impacts, has not been fully assessed. In this paper, the results of a finite element model taking into consideration the heating and cooling demands of a reference building, and the intermittent operation of a ground source heat pump, are revealed to examine the long-term performance of energy piles. Furthermore, a life cycle assessment model is implemented to com…
A solar assisted seasonal borehole thermal energy system for a non-residential building in the Mediterranean area
2019
Abstract Solar heating and cooling systems are reliable and feasible solutions among renewable energy technologies. Indeed, solar thermal devices help reduce primary energy consumption and can reduce electricity demand, thus representing one of the best options for satisfying heating and/or cooling energy supply. The Borehole Thermal Energy Storage (BTES) represents one of the best promising option among the various storage technologies, because the size of the storage can be easily extended by drilling additional boreholes and simply connecting the pipes to the existing boreholes; the overall energy efficiency of this system is about 40–60%. In this paper, the authors present an applicatio…
Sewage sludge as cheap alternative to microalgae as feedstock of catalytic hydrothermal liquefaction processes
2019
Abstract Production of biocrude through hydrothermal liquefaction (HTL) of sewage sludge (SS) and Chlorella vulgaris was investigated. NiMo/Al2O3 (KF 851), CoMo/Al2O3 (KF 1022) and activated carbon felt, tested as catalysts at 598 K for 30 min, did not change the biocrude yield but significantly improved its quality. Quantitative sulfur removal and lower oxygen content were found in biocrude when KF 851 and KF 1022 were used with C. vulgaris. The same catalysts decreased O/C and S/C ratio of the biocrude from SS. The highest HHV (38.19 MJ/kg) and H/C ratio (1.65) and the lowest O/C (0.11) of the biocrude from SS were obtained with the cheaper activated carbon felt. A new product phase, prob…
Energy and economic analysis of air-to-air heat pumps as an alternative to domestic gas boiler heating systems in the South of Italy
2019
Abstract According to the electricity tariff recently issued by the Italian government for the domestic heating systems fed with heat pumps (HP), an energy and economic analysis was carried out with the aim of investigating the effectiveness of the air-to-air heat pump systems (HPS) as an alternative to the traditional heating using domestic gas boilers systems (GBS). For the purpose of this study, the apartments of three residential buildings were examined. The hourly heating loads were calculated with the ASHRAE radiant time series and the coefficient of performance (COP) of the HPs was evaluated for each operating condition. The costs for the heating system installation and electricity a…
Solar and Heat Pump Systems for Domestic Hot Water Production on a Small Island: The Case Study of Lampedusa
2020
The achievement of United Nations Sustainable Development Goals, related to energy and resource use, is a critical issue for small and insulated communities. In many minor islands, solar energy is not correctly exploited, and electrical heaters are connected to weak grids with very a high share of generation by fossil fuels. As a consequence, there is the necessity to assess the potential and the suitability of diffusion of alternative systems to avoid dependency on the electrical grid and reduce carbon emissions. This paper aims to evaluate the technical and economic performances of some alternative systems exploiting renewable energy for domestic hot water production. Four different syste…