The effect of ligand symmetry on the ratiometric luminescence characteristics of lanthanides

2018 ◽  
Vol 47 (19) ◽  
pp. 6779-6786 ◽  
Author(s):  
Yoshinori Okayasu ◽  
Hajime Kamebuchi ◽  
Junpei Yuasa
Keyword(s):  
Temperature Changes ◽  
Spectral Changes ◽  
Response To Temperature ◽  
Luminescence Characteristics

Nona-coordinated europium(iii) complexes incorporating unsymmetrical β-diketonate ligands exhibit distinctive ratiometric spectral changes within the extremely narrow f–f transition bands in response to temperature changes over the range from 253 to 323 K.

scholarly journals LPEATs Tailor Plant Phospholipid Composition through Adjusting Substrate Preferences to Temperature

2021 ◽  
Vol 22 (15) ◽  
pp. 8137
Author(s):  
Sylwia Klińska ◽  
Kamil Demski ◽  
Katarzyna Jasieniecka-Gazarkiewicz ◽  
Antoni Banaś
Keyword(s):  
Growth Regulation ◽  
Phylogenetic Analyses ◽  
Phospholipid Composition ◽  
Expression Ratio ◽  
Temperature Changes ◽  
Substrate Preferences ◽  
Thermal Changes ◽  
Biochemical Evaluation ◽  
Response To Temperature ◽  
Acyl Donors

Acyl-CoA:lysophosphatidylethanolamine acyltransferases (LPEATs) are known as enzymes utilizing acyl-CoAs and lysophospholipids to produce phosphatidylethanolamine. Recently, it has been discovered that they are also involved in the growth regulation of Arabidopsis thaliana. In our study we investigated expression of each Camelina sativa LPEAT isoform and their behavior in response to temperature changes. In order to conduct a more extensive biochemical evaluation we focused both on LPEAT enzymes present in microsomal fractions from C. sativa plant tissues, and on cloned CsLPEAT isoforms expressed in yeast system. Phylogenetic analyses revealed that CsLPEAT1c and CsLPEAT2c originated from Camelina hispida, whereas other isoforms originated from Camelina neglecta. The expression ratio of all CsLPEAT1 isoforms to all CsLPEAT2 isoforms was higher in seeds than in other tissues. The isoforms also displayed divergent substrate specificities in utilization of LPE; CsLPEAT1 preferred 18:1-LPE, whereas CsLPEAT2 preferred 18:2-LPE. Unlike CsLPEAT1, CsLPEAT2 isoforms were specific towards very-long-chain fatty acids. Above all, we discovered that temperature strongly regulates LPEATs activity and substrate specificity towards different acyl donors, making LPEATs sort of a sensor of external thermal changes. We observed the presented findings not only for LPEAT activity in plant-derived microsomal fractions, but also for yeast-expressed individual CsLPEAT isoforms.

scholarly journals Human Erythrocyte-Like Transformation of Synthetic Polymer Vesicles

2021 ◽  
Author(s):  
Eri Yoshida
Keyword(s):  
Methacrylic Acid ◽  
Human Erythrocyte ◽  
Bilayer Membrane ◽  
Synthetic Polymer ◽  
Butyl Methacrylate ◽  
Temperature Changes ◽  
Polymer Vesicles ◽  
Membrane Perforation ◽  
Response To Temperature ◽  
Spherical Vesicles

Abstract This paper describes that synthetic polymer vesicles undergo a human erythrocyte-like transformation in response to temperature changes. The normally biconcave discoid erythrocytes, i.e., the discocytes, are transformed into various shapes by their environmental stresses. Field emission scanning electron microscopy (FE-SEM) demonstrates that the spherical vesicles consisting of poly(methacrylic acid)-block-poly(n-butyl methacrylate-random-methacrylic acid), PMAA-b-P(BMA-r-MAA), transform into echinocyte-like crenate vesicles due to expansion by the component copolymers in being freed from the vesicle surface when heated in an aqueous methanol solution. An increase in the vesicle concentration transforms the spherical vesicles into stomatocyte-like cup-shaped vesicles via the membrane perforation or double invaginations followed by membrane coupling and fusion. Light scattering studies reveal the reversibility and repeatability of the transformations. These findings indicate that the erythrocyte transformations are attributed to the inherent property of the bilayer membrane. The polymer vesicles are helpful for a better understanding of the biomembrane.

Preparation and Swelling Dynamics Characterization of Poly(N, N-Diethylacrylamide-Co-Itaconic Acid) Intelligent Hydrogels

2012 ◽  
Vol 490-495 ◽  
pp. 3382-3386
Author(s):  
Xiao Qi Li ◽  
Nai Yan Zhang ◽  
Jun Hai Zhang
Keyword(s):  
Itaconic Acid ◽  
Monomer Concentration ◽  
Molar Ratio ◽  
Solution Temperature ◽  
Temperature Changes ◽  
Different Temperatures ◽  
Total Monomer Concentration ◽  
Equilibrium Swelling Ratio ◽  
Composition Ratios ◽  
Response To Temperature

Poly(N,N-diethylacrylamide) (PDEA) hydrogel is known for their intelligent reversible swelling/deswelling behavior in response to temperature changes across a lower critical solution temperature (LCST) at around 31oC. In this study, itaconic acid (IA) was co-polymerized with N, N-diethylacrylamide (DEA) monomer to improve the swelling behavior and the total absorbing water. These copolymer hydrogels were prepared by changing the initial DEA/IA molar ratio and total monomer concentration. The chemical structure of hydrogels was characterized by fourier transform infrared (FTIR) spectroscopy. In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) of the hydrogels increase with the increase of IA content in the feed and the swelling dynamics behaviors of the different composition ratios of the P(DEA-co-IA) hydrogels on the different temperatures was investigated in detail.

Response of Two Arctic Amphipods, Gammarus zaddachi and Boeckosimus (Onisimus) affinis, to Variations in Temperature and Salinity

1975 ◽  
Vol 32 (12) ◽  
pp. 2564-2568 ◽  
Author(s):  
M. Busdosh ◽  
Ronald M. Atlas
Keyword(s):  
Respiration Rate ◽  
Ecological Distribution ◽  
Temperature Changes ◽  
Gammarus Zaddachi ◽  
Wide Range ◽  
Abrupt Changes ◽  
Response To Temperature

Two arctic amphipods were found to be capable of tolerating a wide range of temperatures and salinities. They were tolerant to both abrupt changes, as would occur in crossing a thermocline, and to gradual changes, as would occur seasonally.Gammarus zaddachi could survive lower salinities and higher temperatures than Boeckosimus (Onisimus) affinis. Salinity had a statistically significant effect on rates of respiration for both organisms, but only Gammarus zaddachi showed significant changes in respiration rate in response to temperature changes. The ecological distribution of these amphipods appears to be in part determined by their ability to tolerate fluctuations in salinity and temperature.

Feedback regulation of COOLAIR expression controls seed dormancy and flowering time

Science ◽  
2018 ◽  
Vol 360 (6392) ◽  
pp. 1014-1017 ◽  
Author(s):  
Min Chen ◽  
Steven Penfield
Keyword(s):  
Flowering Time ◽  
Seed Dormancy ◽  
Feedback Regulation ◽  
Day Length ◽  
Developmental Transitions ◽  
Temperature Changes ◽  
Plant Uses ◽  
Seasonal Signals ◽  
Flowering Locus ◽  
Response To Temperature

Plants integrate seasonal signals, including temperature and day length, to optimize the timing of developmental transitions. Seasonal sensing requires the activity of two proteins, FLOWERING LOCUS C (FLC) and FLOWERING LOCUS T (FT), that control certain developmental transitions in plants. During reproductive development, the mother plant uses FLC and FT to modulate progeny seed dormancy in response to temperature. We found that for regulation of seed dormancy, FLC and FT function in opposite configuration to how those same genes control time to flowering. For seed dormancy, FT regulates seed dormancy through FLC gene expression and regulates chromatin state by activating antisense FLC transcription. Thus, in Arabidopsis the same genes controlled in opposite format regulate flowering time and seed dormancy in response to the temperature changes that characterize seasons.

scholarly journals The effect of temperature on the electronic spectra of octahedral iron(II) complexes

1968 ◽  
Vol 21 (12) ◽  
pp. 2859 ◽  
Author(s):  
G Winter
Keyword(s):  
Electronic Spectra ◽  
Tetragonal Distortion ◽  
Effect Of Temperature ◽  
Temperature Changes ◽  
Spectral Changes ◽  
Band Separation

Spectral changes in iron(11) complexes caused by temperature changes have been examined. When the iron(11) ion is surrounded by six equivalent ligands (FeC12, FeBr2, FeI2, FeSiF6,6H2O) the band separation that arises from the splitting of the 5Eg level decreases on cooling. The variation is proportional to the magnitude of the band separation. In complexes with tetragonal distortion (FeCl2,2H20, FeCl2,- 2CH3OH,FeCl2,4pyridine, FeCl2,2pyridine, FeCl2,4isoquinoline, FeBr2,4isoquinoline) the variation in band separation with change in temperature is smaller and is inversely related to the magnitude of the band separation.

Actuator Applications with Single-Crystals of Cu-Zn-Al Shape Memory Alloy

1996 ◽  
Vol 459 ◽  
Author(s):  
A. A. Yawny ◽  
M. Sade ◽  
F. C. Lovey
Keyword(s):  
Single Crystal ◽  
Shape Memory ◽  
Single Crystals ◽  
Load Level ◽  
Cycle Number ◽  
Temperature Changes ◽  
Friction Temperature ◽  
Response To Temperature ◽  
Thermostatic Device ◽  
Experimental Stage

ABSTRACTIn the present work the use of single-crystals of Cu-Zn-Al Shape Memory Alloys (SMA) in actuator applications is analyzed. The actuator considered here, a device capable of doing work in response to temperature changes, is based on a single-crystal nucleus of a Cu-Zn-Al SMA coupled to a conventional spring that represents the load to be displaced. A special experimental stage was designed for performing controlled thermal cycles under load. In this way the effects of different parameters (cycle number, friction, temperature range, load level) on the actuator behavior can be studied. From the results obtained, the use of a single-crystal of an SMA in a thermostatic device is analyzed and compared with the commercial wax actuator performance.

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