EFFECTS OF LONG TERM EXPOSURE TO LOW TEMPERATURE ON THE PHOTOSYNTHETIC APPARATUS OF DUNALIELLA TERTIOLECTA (CHLOROPHYCEAE)1

1990 ◽  
Vol 26 (3) ◽  
pp. 479-484 ◽  
Author(s):  
Maurice E. Levasseur ◽  
Jean-Claude Morissette ◽  
Radovan Popovic ◽  
Paul J. Harrison
Keyword(s):  
Low Temperature ◽  
Photosynthetic Apparatus ◽  
Dunaliella Tertiolecta

scholarly journals Adaptation of flocculent anammox culture to low temperature by cold shock: long-term response of microbial population

2021 ◽  
pp. 1-19
Author(s):  
Vojtech Kouba ◽  
Juan Camilo Gerlein ◽  
Andrea Benakova ◽  
Marco Antonio Lopez Marin ◽  
Eva Rysava ◽  
...  
Keyword(s):  
Low Temperature ◽  
Cold Shock ◽  
Microbial Population ◽  
Term Response

scholarly journals Compensation Mechanism of the Photosynthetic Apparatus in Arabidopsis thaliana ch1 Mutants

2020 ◽  
Vol 22 (1) ◽  
pp. 221
Author(s):  
Joanna Wójtowicz ◽  
Adam K. Jagielski ◽  
Agnieszka Mostowska ◽  
Katarzyna B. Gieczewska
Keyword(s):  
Light Stress ◽  
Photosynthetic Apparatus ◽  
Protein Composition ◽  
Mrna Levels ◽  
Chlorophyll B ◽  
Low Light ◽  
Plant Acclimation ◽  
Chlorophyll B Deficiency ◽  
Composition Changes

The origin of chlorophyll b deficiency is a mutation (ch1) in chlorophyllide a oxygenase (CAO), the enzyme responsible for Chl b synthesis. Regulation of Chl b synthesis is essential for understanding the mechanism of plant acclimation to various conditions. Therefore, the main aim of this study was to find the strategy in plants for compensation of low chlorophyll content by characterizing and comparing the performance and spectral properties of the photosynthetic apparatus related to the lipid and protein composition in four selected Arabidopsis ch1 mutants and two Arabidopsis ecotypes. Mutation in different loci of the CAO gene, viz., NW41, ch1.1, ch1.2 and ch1.3, manifested itself in a distinct chlorina phenotype, pigment and photosynthetic protein composition. Changes in the CAO mRNA levels and chlorophyllide a (Chlide a) content in ecotypes and ch1 mutants indicated their significant role in the adjustment mechanism of the photosynthetic apparatus to low-light conditions. Exposure of mutants with a lower chlorophyll b content to short-term (1LL) and long-term low-light stress (10LL) enabled showing a shift in the structure of the PSI and PSII complexes via spectral analysis and the thylakoid composition studies. We demonstrated that both ecotypes, Col-1 and Ler-0, reacted to high-light (HL) conditions in a way remarkably resembling the response of ch1 mutants to normal (NL) conditions. We also presented possible ways of regulating the conversion of chlorophyll a to b depending on the type of light stress conditions.

scholarly journals Design of a Database of Case Studies and Technologies to Increase the Diffusion of Low-Temperature Waste Heat Recovery in the Industrial Sector

2021 ◽  
Vol 13 (9) ◽  
pp. 5223
Author(s):  
Miriam Benedetti ◽  
Daniele Dadi ◽  
Lorena Giordano ◽  
Vito Introna ◽  
Pasquale Eduardo Lapenna ◽  
...  
Keyword(s):  
Low Temperature ◽  
Case Studies ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Industrial Sector ◽  
Implementation Rate ◽  
Depth Analysis ◽  
Technology Market

The recovery of waste heat is a fundamental means of achieving the ambitious medium- and long-term targets set by European and international directives. Despite the large availability of waste heat, especially at low temperatures (<250 °C), the implementation rate of heat recovery interventions is still low, mainly due to non-technical barriers. To overcome this limitation, this work aims to develop two distinct databases containing waste heat recovery case studies and technologies as a novel tool to enhance knowledge transfer in the industrial sector. Through an in-depth analysis of the scientific literature, the two databases’ structures were developed, defining fields and information to collect, and then a preliminary population was performed. Both databases were validated by interacting with companies which operate in the heat recovery technology market and which are possible users of the tools. Those proposed are the first example in the literature of databases completely focused on low-temperature waste heat recovery in the industrial sector and able to provide detailed information on heat exchange and the technologies used. The tools proposed are two key elements in supporting companies in all the phases of a heat recovery intervention: from identifying waste heat to choosing the best technology to be adopted.

Effect of Anticonvulsants on the Uptake of 5-Methyltetrahydrofolic Acid by the Choroid Plexus in Rabbits

1977 ◽  
Vol 53 (1) ◽  
pp. 75-80
Author(s):  
H. Taguchi ◽  
Z. Abdul-Cader ◽  
J. Perry ◽  
E. H. Reynolds ◽  
I. Chanarin
Keyword(s):  
Folic Acid ◽  
Low Temperature ◽  
Choroid Plexus ◽  
Incubation Medium ◽  
Pernicious Anaemia ◽  
Inhibitory Effect ◽  
Anaerobic Conditions ◽  
Acid Therapy ◽  
Pteroylglutamic Acid

1. The isolated choroid plexus of the rabbit takes up 5-methyltetrahydrofolate from the incubation medium. 2. Other folate analogues (pteroylglutamic acid, methotrexate, 5-formyltetrahydrofolate = folinic acid) inhibited the uptake of 5-methyltetrahydrofolate. 3. The uptake of 5-methyltetrahydrofolate was inhibited by low temperature, anaerobic conditions and dinitrophenol. 4. The anticonvulsant drugs, diphenylhydantoin and phenobarbital, had no effect on 5-methyltetrahydrofolate uptake. 5. The inhibitory effect of pteroylglutamic acid on the uptake of 5-methyltetrahydrofolate by the choroid plexus may explain the effect of long-term folic acid therapy in aggravating vitamin B12 neuropathy in pernicious anaemia.

Evidence for the Role of Water in Ch4 Generation from Long-Term, Low Temperature Experimental Maturation of Immature Shales

2021 ◽  
Author(s):  
K. Doiron ◽  
P. Sauer ◽  
A. Schimmelmann ◽  
M. Mastalerz ◽  
A. Drobniak ◽  
...  
Keyword(s):  
Low Temperature

scholarly journals COMPARATIVE ANALYSIS OF LOW TEMPERATURE RESISTANCE FOR NANOCARBON AND OTHER BITUMENS

2020 ◽  
Vol 5 (443) ◽  
pp. 89-96
Author(s):  
Zhurinov M.Zh., ◽  
◽  
Teltayev B.B., ◽  
Kalybay A.A., ◽  
Rossi C.O., ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Low Temperature ◽  
Polyphosphoric Acid ◽  
Crumb Rubber ◽  
Petrochemical Plant ◽  
Short Term ◽  
Temperature Resistance ◽  
Coal Rock ◽  
Low Temperature Resistance

A comparative analysis of the low temperature resistance for a nanocarbon bitumen and other 30 neat and modified bitumens has been performed in the work. The stiffness at the temperatures of -24°С, -30°С and -36°С under technical system Superpave has been accepted as an indicator of low temperature resistance of the bitumens. The stiffness of the bitumens has been determined on a bending beam rheometer (standard ASTM D 6648-08). Before testing the bitumens have been subjected to the double artificial aging: short-term aging – under standard AASHTO Т 240-13 and long-term aging – under standard ASTM D 6521-08. The nanocarbon bitumen has been prepared in the laboratory of the Kazakhstan Highway Research Institute (KazdorNII) with the use of a road bitumen of the grade BND 70/100 produced by the Pavlodar petrochemical plant (PNHZ) and a nanocarbon powder (2% by weight) manufactured from a coal rock of the deposit “Saryadyr” “Corporation “ON-Olzha” LLP, Akmola region, Kazakhstan). The nanocarbon powder (150-200 nm) has been manufactured by three-stage size reduction of the coal rock: I – a mechanical dispergator (up to 2-3 mm), II – an aerodynamic mill (up to 20 mcm), III – a reactor with a rotating electromagnetic field. The neat bitumens of the grades BND 50/70, BND 70/100, BND 100/130 have been produced by the plants of Kazakhstan and Russia; they satisfy the requirements of the standard ST RK 1373-2013. The modified bitumens have been prepared in the laboratory of KazdorNII with the use of the neat bitumens, 7 types of the polymers, crumb rubber and polyphosphoric acid and they satisfy the requirements of the standard ST RK 2534-2014. It has been determined that the nanocarbon bitumen is one of the most resistant at the low temperatures: -24°С, -30°С and -36°С.

Influence Analysis of Performance on Sasobit Warm Mix Asphalt with Salinity

2014 ◽  
Vol 490-491 ◽  
pp. 138-141
Author(s):  
Kun Wang ◽  
Jing Ya Chen ◽  
Xiang Qu
Keyword(s):  
Low Temperature ◽  
Environmental Benefits ◽  
Fatigue Performance ◽  
Test Results ◽  
Temperature Performance ◽  
Cracking Performance ◽  
Low Temperature Cracking ◽  
Short And Long Term ◽  
Analysis Of Performance

Sasobit warm mix drainage asphalt pavement has become increasingly popular due to its environmental benefits and comfortable using effect. However, test results show that its low-temperature and anti-fatigue performance have a certain degree of reduced. To improve the performance of asphalt four different doses (1%, 3%, 5% and 7%) of salt are added to the Sasobit asphalt. Laboratory tests were used to simulate short and long term aging asphalt in the process of construction and using pavement. A series of binder tests including bending beam rheometer (BBR), dynamic shear rheometer (DSR) and Brookfield viscosity tests were conducted. Results show an increase of rutting performance for warm mix binders with Sasobit while asphalt with salt has similar high temperature performance to original asphalt. Unlike Sasobit which has a decrease of cracking performance for asphalt at low-temperature, salinity can greatly improve the Low-temperature performance. And the low-temperature cracking performance and anti-fatigue performance presents a tendency of climbing up first and then declining with the increase of salinity. The figure of viscosity-temperature curve shows that the optimum of salinity is 5%.Further more, asphalt with Sasobit and salt can gain better performance and same mixing and compaction effect in lower 20°C than hot mix asphalt without it.

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