Search results for "ACCLIMATION"

Integration of polyamins in the cold acclimation response

2011

8 páginas, 1 figura, 3 tablas -- PAGS nros. 31-38

Acid stress in respect to calcium and magnesium concentrations in the plasma of perch during maturation and spawning

1988

Plasma calcium and magnesium concentrations in perch,Perca fluviatilis, were monitored in an acid lake, Lake Iso Tenhetty (pH ∼5, Al concentrations 0.3–0.5 mg l-1) compared with a nearby reference lake, Lake Paijanne, in Southern Finland. The effect of acid stress could be noticed as 1/3 lower fecundity of perch in the acid lake. Plasma Ca concentrations were temporarily lower in the middle of the winter in the fish of the acid lake, and in April–May samples the situation was opposite. Plasma Mg concentration was also lower in the perch from the acid lake in midwinter months, when compared with the double as high values (∼3 mmol l-1) from the reference lake. Elevated level of plasma Mg have…

Homeostatic control of polyamine levels under long-term salt stress in Arabidopsis

2011

Salt stress has been frequently studied in its first osmotic phase. Very often, data regarding the second ionic phase is missing. It has also been suggested that Putrescine or/and Spermine could be responsible for salt resistance. In order to test this hypothesis under long-term salt stress, we obtained Arabidopsis thaliana transgenic plants harboring pRD29A::oatADC or pRD29A::GUS construction. Although Putrescine was the only polyamine significantly increased after salt acclimation in pRD29A::oatADC transgenic lines, this rendered in no advantage to this kind of stress. The higher Spermine levels found in WT and transgenic lines when compared to control conditions along with no increment o…

Influence of the methodology of inoculation in the performance of air-breathing microbial fuel cells

2017

n this work, four air-breathing microbial fuel cells (AB-MFC) were operated for 1 month in order to determine if the methodology of inoculation affects the steady-state performance of this type of MFCs. For this purpose, anaerobic and aerobic sludge were fed to two identical AB-MFCs without any external carbon source into a tight sealed environment during the first three days of start-up. For comparison purposes, other two AB-MFCs were operated mixing the initial sludge and an amount of sodium acetate as substrate. Results point out that the inoculation procedure does not affect the steady-state treatment capacity of the cells but it affects very seriously the production of electricity. Onl…

Influence of the initial sludge characteristics and acclimation on the longterm performance of double-compartment acetate-fed microbial fuel cells

2018

Abstract In this work, three double-compartment MFCs (DC-MFC) were operated for 1 month in order to compare their performances in terms of wastewater treatment capacity and electricity production and to get information about how this performance is influenced by the start-up procedure. To do this, they underwent different start-up procedures. One of them (aerobic-starved MFC) was inoculated with 100% fresh aerobic sludge, another (anaerobic-starved MFC) using 100% fresh anaerobic sludge, and finally a third one (aerobic-fed MFC) was inoculated using a mixture 10% fresh aerobic sludge and 90% synthetic wastewater (based on acetate). Then, from this start-up, the cells were operated exactly u…

Photoperiodic regulation of cold tolerance and expression levels of regucalcin gene in Drosophila montana

2011

Temperature-induced plasticity of cold tolerance has been reported in many insect species, but cold tolerance can also be affected by changes in day (or night) length. In the present study we elucidate the direct and indirect effects of photoperiod on the cold tolerance of females of two Drosophila montana strains--one which possesses a robust photoperiodic diapause and another which does not. In the diapause-strain the time needed for recovery from chill coma showed a positive correlation with day length, but diapause itself played only a minor role in photoperiodic acclimation. The strain that was not able to enter to diapause as a response to day length also lacked photoperiodic cold acc…

Evolution rétrospective du risque gélif hivernal en climat tempéré suite au réchauffement climatique

2018

Prod 2019-139 BAP POLE EA GEAPSI INRA AGROSUP; National audience; Les modalités du réchauffement climatique sur l’Europe de l’ouest montrent pour les températures une rupture nette en 1987/1988. Deux régimes distincts de température ont eu cours de part et d’autre de cette rupture. Cela offre une opportunité pour évaluer un impact du réchauffement en Bourgogne Franche-Comté. Peu de travaux documentent néanmoins les conséquences du réchauffement hivernal sur la végétation en général et les cultures en particulier. Pourtant, ces dernières années, des travaux suggèrent une augmentation du risque gélif présentée comme un effet paradoxal du réchauffement climatique. En combinant, sur la période …

2016

Cold acclimation is a critical physiological adaptation for coping with seasonal cold. By increasing their cold tolerance individuals can remain active for longer at the onset of winter and can recover more quickly from a cold shock. In insects, despite many physiological studies, little is known about the genetic basis of cold acclimation. Recently, transcriptomic analyses in Drosophila virilis and D. montana revealed candidate genes for cold acclimation by identifying genes upregulated during exposure to cold. Here, we test the role of myo-inositol-1-phosphate synthase (Inos), in cold tolerance in D. montana using an RNAi approach. D. montana has a circumpolar distribution and overwinters…

Influence of Altered Microbes on Soil Organic Carbon Availability in Karst Agricultural Soils Contaminated by Pb-Zn Tailings.

2018

Soil organic carbon (SOC) availability is determined via a complex bio-mediated process, and Pb-Zn tailings are toxic to the soil microbes that are involved in this process. Here, Pb-Zn-tailings- contaminated karst soils with different levels (paddy field > corn field > citrus field > control group) were collected to explore the intrinsic relationship between Pb-Zn tailings and microbes due to the limited microbial abundance in these soils. The SOC concentration in the paddy fields is the highest. However, based on the soil microbial diversity and sole-carbon-source utilization profiles, the rate of SOC availability, McIntosh index, Shannon-Wiener diversity index, Simpson’s diversi…

Extremely rapid acclimation of Escherichia coli to high temperature over a few generations of a fed-batch culture during slow warming

2014

This study aimed to demonstrate that adequate slow heating rate allows two strains of Escherichia coli rapid acclimation to higher temperature than upper growth and survival limits known to be strain-dependent. A laboratory (K12-TG1) and an environmental (DPD3084) strain of E. coli were subjected to rapid (few seconds) or slow warming (1 degrees C 12 h(-1)) in order to (re) evaluate upper survival and growth limits. The slow warming was applied from the ancestral temperature 37 degrees C to total cell death 46-54 degrees C: about 30 generations were propagated. Upper survival and growth limits for rapid warming (46 degrees C) were lower than for slow warming (46-54 degrees C). The thermal l…