scholarly journals Spectroscopic and Molecular Modeling Investigation on the Interaction between Folic Acid and Bovine Lactoferrin from Encapsulation Perspectives

Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 744
Author(s):  
Iuliana Aprodu ◽  
Loredana Dumitrașcu ◽  
Gabriela Râpeanu ◽  
Gabriela-Elena Bahrim ◽  
Nicoleta Stănciuc
Keyword(s):  
Folic Acid ◽  
Molecular Modeling ◽  
Thermal Treatment ◽  
Tertiary Structure ◽  
Emission Spectra ◽  
Bovine Lactoferrin ◽  
Different Temperatures ◽  
Static Mechanism ◽  
Increasing Temperature ◽  
The Impact

The impact of thermal treatment on the ability of lactoferrin (FL) to bind folic acid (FA) was investigated by employing fluorescence spectroscopy, molecular dynamics and docking tests. The structural and conformational particularities of LF upon heating at 80 °C and 100 °C were first estimated based on the intrinsic fluorescence changes in respect to the native protein. The emission spectra indicated gradual unfolding events accompanied by Trp exposure with increasing temperature. In agreement with the experimental results, molecular modeling investigations showed that the secondary and tertiary structure of LF are slightly affected by the thermal treatment. Some minor unfolding events related particularly to the α-helical regions of LF were observed when the temperature increased to 100 °C. The LF fluorescence quenching upon FA addition indicated that a static mechanism stands behind LF-FA complex formation. Regardless of the simulated temperature, the hydrogen bonds played an important role in regulating the interaction between the protein and ligand. FA binding to LF equilibrated at different temperatures occurred spontaneously, and all complexes displayed good thermodynamic stability. The obtained results support the suitability of LF as biocompatible material, for obtaining micro- and nanoparticles for delivery of dietary supplements or for enhancing the functionality of target delivery systems.

Temperature Dependence of Hole Impact Ionization Coefficient in 4H-SiC Photodiodes

2009 ◽  
Vol 615-617 ◽  
pp. 311-314 ◽  
Author(s):  
W.S. Loh ◽  
J.P.R. David ◽  
B.K. Ng ◽  
Stanislav I. Soloviev ◽  
Peter M. Sandvik ◽  
...  
Keyword(s):  
Phonon Scattering ◽  
Impact Ionization ◽  
Positive Temperature Coefficient ◽  
Positive Temperature ◽  
Different Temperatures ◽  
Ionization Coefficients ◽  
Increasing Temperature ◽  
The Impact ◽  
Good Agreement ◽  
Ionization Rates

Hole initiated multiplication characteristics of 4H-SiC Separate Absorption and Multiplication Avalanche Photodiodes (SAM-APDs) with a n- multiplication layer of 2.7 µm were obtained using 325nm excitation at temperatures ranging from 300 to 450K. The breakdown voltages increased by 200mV/K over the investigated temperature range, which indicates a positive temperature coefficient. Local ionization coefficients, including the extracted temperature dependencies, were derived in the form of the Chynoweth expression and were used to predict the hole multiplication characteristics at different temperatures. Good agreement was obtained between the measured and the modeled multiplication using these ionization coefficients. The impact ionization coefficients decreased with increasing temperature, corresponding to an increase in breakdown voltage. This result agrees well with the multiplication characteristics and can be attributed to phonon scattering enhanced carrier cooling which has suppressed the ionization process at high temperatures. Hence, a much higher electric field is required to achieve the same ionization rates.

scholarly journals Drosophilaembryogenesis scales uniformly across temperature and developmentally diverse species

2013 ◽  
Author(s):  
Steven Gregory Kuntz ◽  
Michael B Eisen
Keyword(s):  
Thermal Environment ◽  
Time Lapse ◽  
Egg Laying ◽  
Tropical Species ◽  
Relative Timing ◽  
Animal Development ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
Time Lapse Imaging ◽  
The Impact

Temperature affects both the timing and outcome of animal development, but the detailed effects of temperature on the progress of early development have been poorly characterized. To determine the impact of temperature on the order and timing of events duringDrosophila melanogasterembryogenesis, we used time-lapse imaging to track the progress of embryos from shortly after egg laying through hatching at seven precisely maintained temperatures between 17.5°C and 32.5°C. We employed a combination of automated and manual annotation to determine when 36 milestones occurred in each embryo.D. melanogasterembryogenesis takes 33 hours at 17.5°C, and accelerates with increasing temperature to a low of 16 hours at 27.5°C, above which embryogenesis slows slightly. Remarkably, while the total time of embryogenesis varies over two fold, the relative timing of events from cellularization through hatching is constant across temperatures. To further explore the relationship between temperature and embryogenesis, we expanded our analysis to cover ten additionalDrosophilaspecies of varying climatic origins. Six of these species, likeD. melanogaster, are of tropical origin, and embryogenesis time at different temperatures was similar for them all.D. mojavensis, a sub-tropical fly, develops slower than the tropical species at lower temperatures, whileD. virilis, a temperate fly, exhibits slower development at all temperatures. The alpine sister speciesD. persimilisandD. pseudoobscuradevelop as rapidly as tropical flies at cooler temperatures, but exhibit diminished acceleration above 22.5°C and have drastically slowed development by 30°C. Despite ranging from 13 hours forD. erectaat 30°C to 46 hours forD. virilisat 17.5°C, the relative timing of events from cellularization through hatching is constant across all of the species and temperatures examined here, suggesting the existence of a previously unrecognized timer controlling the progress of embryogenesis that has been tuned by natural selection in response to the thermal environment in which each species lives.

Investigation of Impact Behavior of TIG Welded Inconel 718 at Aircraft Engine Operating Temperatures

2017 ◽  
Vol 890 ◽  
pp. 339-343
Author(s):  
Yagiz Uzunonat
Keyword(s):  
Inconel 718 ◽  
Impact Resistance ◽  
Aircraft Engine ◽  
Impact Behavior ◽  
Spectroscopy Analysis ◽  
Carbide Phases ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
The Impact ◽  
Pendulum Impact

In this work, Charpy notch pendulum impact test was performed on non-welded and TIG (Tungsten Inert Gas) welded Inconel 718 specimens at three different temperatures as 20°C, 500°C and 700°C. After the completion of tests, SEM (Scanning Electron Microscopy) inspection and EDX (Energy-Dispersive X-Ray Spectroscopy) analysis were performed for the microstructural examination of the specimens. Hardness measurements on the rupture zone of selected welded and non-welded specimens were also performed to make a better approach to interpretation of the impact behavior of material. Inspections indicated that hardness values in the heat affected zone of welded specimens dramatically decreased and they displayed higher ductility during fracture than non-welded samples due to partial softening of structure. The reason of further decrease in impact resistance of welded specimens was explained as the precipitation and coarsening of γ′′ and carbide phases in the interdendritic regions with increasing temperature.

scholarly journals Effects of Thermal Treatment on Mineral Composition and Pore Structure of Coal

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Bin Liu ◽  
Teng Teng ◽  
Zhenhua Jiao ◽  
Shaobo Li
Keyword(s):  
Thermal Treatment ◽  
Pore Structure ◽  
Mineral Composition ◽  
Coalbed Methane ◽  
Pore Diameter ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
Main Factor

With the increasing depth of coalbed methane (CBM) exploitation, temperature becomes the main factor affecting the efficiency of CBM exploitation. The change of temperature has significant influence on the mineral composition and pore structure of coal. To study the effects of thermal treatment on mineral composition and pore structure of coal, X-ray diffraction (XRD) test, scanning electron microscopy (SEM) test, and mercury intrusion test were carried out for three groups of coal. The mineral composition and pore structure of coal specimens after thermal treatment (25, 50, 75, and 100°C) were analyzed. The results show that the main mineral compositions of three groups of coal specimens after different temperatures are basically unchanged, and the maximum diffracted intensity after different temperature treatments decreases first and then increases with the increasing temperature. The count of fissures decreases first and then increases with temperature, and the count of pores increases first and then decreases with the increasing temperature. The velocity of mercury injection in high pressure (100~400 MPa) of coal specimens increases first and then decreases with temperature. The porosity, pore area, median pore diameter, and average pore diameter increase with the increasing temperatures. The volume of microfracture decreases, then increases, and finally decreases. The volume of macropore and mesopore increases slowly, and that of transition pore decreases slowly with the increasing temperature. Meanwhile, the volume of micropore increases first and then decreases during the process of thermal treatment. The fractal dimension of pore size ranges from 2.6 to 2.9 and increases linearly with the increasing temperature.

Innovative approaches to the correction of chronotrope status of pregnant and lactating women

2016 ◽  
pp. 37-40
Author(s):  
S.I. Zhuk ◽  
◽  
K.K. Bondarenko ◽  
Keyword(s):  
Folic Acid ◽  
Neural Tube ◽  
Active Form ◽  
Biologically Active ◽  
Lactating Women ◽  
Pathological Conditions ◽  
Prevention And Treatment ◽  
The Impact ◽  
High Bioavailability ◽  
Key Words Mthfr

Most recent studies show the impact of violations in the metabolism of folate and metin period in the pathogenesis of neural tube defects (NTD) of the fetus. Metafolin has a number of advantages, which primarily includes direct intake of substances in biologically active form and the optimum effect, even in the case when the patient homozygote and/or heterozygote genotype 677С T polymorphism in MTHFR. With the aim of prevention and treatment of various pathological conditions related to folate deficiency during pregnancy, it is advisable to apply vitamin-mineral complexes, containing metafolin - active form of folate with high bioavailability. Key words: MTHFR, metafolin, folic acid, pregnancy.

Static and Dynamic Studies of Gasoline in View of its Octane Number and its Toxic Effect

2013 ◽  
Vol 12 (7) ◽  
pp. 451-459
Author(s):  
Ashraf Yehia El-Naggar ◽  
Mohamed A. Ebiad
Keyword(s):  
Toxic Effect ◽  
Aromatic Hydrocarbons ◽  
Octane Number ◽  
Liquid Fuel ◽  
Positive Impact ◽  
Hydrocarbon Composition ◽  
Different Temperatures ◽  
Different Seasons ◽  
The One ◽  
The Impact

Gasoline come primarily from petroleum cuts, it is the preferred liquid fuel in our lives. Two gasoline samples of octane numbers 91 and 95 from Saudi Arabia petrol stations were studied. This study was achieved at three different temperatures 20oC, 30oC and 50oC representing the change in temperatures of the different seasons of the year. Both the evaporated gases of light aromatic hydrocarbons (BTEX) of gasoline samples inside the tank were subjected to analyze qualitatively and quantitatively via capillary gas chromatography. The detailed hydrocarbon composition and the octane number of the studied gasoline samples were determined using detailed hydrocarbon analyzer. The idea of research is indicating the impact of light aromatic compounds in gasoline on the toxic effect of human and environment on the one hand, and on octane number of gasoline on the other hand. Although the value of octane number will be reduced but this will have a positive impact on the environment as a way to produce clean fuel.

scholarly journals Effect of temperature, CO2 and O2 on motility and mobility of Anisakidae larvae

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aiyan Guan ◽  
Inge Van Damme ◽  
Frank Devlieghere ◽  
Sarah Gabriël
Keyword(s):  
Enzymatic Digestion ◽  
Infected Fish ◽  
Effect Of Temperature ◽  
Video Recordings ◽  
Different Temperatures ◽  
Semi Solid ◽  
Zoonotic Parasites ◽  
The Impact ◽  
Phosphate Buffered Saline

AbstractAnisakidae, marine nematodes, are underrecognized fish-borne zoonotic parasites. Studies on factors that could trigger parasites to actively migrate out of the fish are very limited. The objective of this study was to assess the impact of different environmental conditions (temperature, CO2 and O2) on larval motility (in situ movement) and mobility (migration) in vitro. Larvae were collected by candling or enzymatic digestion from infected fish, identified morphologically and confirmed molecularly. Individual larvae were transferred to a semi-solid Phosphate Buffered Saline agar, and subjected to different temperatures (6 ℃, 12 ℃, 22 ℃, 37 ℃) at air conditions. Moreover, different combinations of CO2 and O2 with N2 as filler were tested, at both 6 °C and 12 °C. Video recordings of larvae were translated into scores for larval motility and mobility. Results showed that temperature had significant influence on larval movements, with the highest motility and mobility observed at 22 ℃ for Anisakis spp. larvae and 37 ℃ for Pseudoterranova spp. larvae. During the first 10 min, the median migration of Anisakis spp. larvae was 10 cm at 22 ℃, and the median migration of Pseudoterranova spp. larvae was 3 cm at 37 ℃. Larval mobility was not significantly different under the different CO2 or O2 conditions at 6 °C and 12 ℃. It was concluded that temperature significantly facilitated larval movement with the optimum temperature being different for Anisakis spp. and Pseudoterranova spp., while CO2 and O2 did not on the short term. This should be further validated in parasite-infected/spiked fish fillets.

scholarly journals A Comparative Electrochemical and Morphological Investigation on the Behavior of NiCr and CoCr Dental Alloys at Various Temperatures

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 256
Author(s):  
Florentina Golgovici ◽  
Mariana Prodana ◽  
Florentina Gina Ionascu ◽  
Ioana Demetrescu
Keyword(s):  
Low Temperatures ◽  
Artificial Saliva ◽  
Electrochemical Stability ◽  
Morphological Investigation ◽  
Dental Alloys ◽  
Ion Release ◽  
Icp Ms ◽  
Different Temperatures ◽  
Good Concordance ◽  
Increasing Temperature

The purpose of our study is to compare the behavior of two reprocessed dental alloys (NiCr and CoCr) at different temperatures considering the idea that food and drinks in the oral cavity create various compositions at different pH levels; the novelty is the investigation of temperature effect on corrosion parameters and ion release of dental alloys. Electrochemical stability was studied together with morphology, elemental composition and ions release determination. The results obtained are in good concordance: electrochemistry studies reveal that the corrosion rate is increasing by increasing the temperature. From SEM coupled with EDS, the oxide film formed on the surface of the alloys is stable at low temperatures and a trend to break after 310K. ICP-MS results evidence that in accordance with increasing temperature, the quantities of ions released from the alloys immersed in artificial saliva also increase, though they still remain small, less than 20 ppm.

scholarly journals Low-carbon cast microalloyed steel intercritically heat-treated at different temperatures: microstructure and mechanical properties

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Hadi Torkamani ◽  
Shahram Raygan ◽  
Carlos Garcia Mateo ◽  
Yahya Palizdar ◽  
Jafar Rassizadehghani ◽  
...  
Keyword(s):  
Carbon Content ◽  
Volume Fraction ◽  
Block Size ◽  
Tensile Tests ◽  
Total Elongation ◽  
Martensite Phase ◽  
Low Carbon ◽  
Steel Increase ◽  
Different Temperatures ◽  
The Impact

AbstractIn this study, dual-phase (DP, ferrite + martensite) microstructures were obtained by performing intercritical heat treatments (IHT) at 750 and 800 °C followed by quenching. Decreasing the IHT temperature from 800 to 750 °C leads to: (i) a decrease in the volume fraction of austenite (martensite after quenching) from 0.68 to 0.36; (ii) ~ 100 °C decrease in martensite start temperature (Ms), mainly due to the higher carbon content of austenite and its smaller grains at 750 °C; (iii) a reduction in the block size of martensite from 1.9 to 1.2 μm as measured by EBSD. Having a higher carbon content and a finer block size, the localized microhardness of martensite islands increases from 380 HV (800 °C) to 504 HV (750 °C). Moreover, despite the different volume fractions of martensite obtained in DP microstructures, the hardness of the steels remained unchanged by changing the IHT temperature (~ 234 to 238 HV). Applying lower IHT temperature (lower fraction of martensite), the impact energy even decreased from 12 to 9 J due to the brittleness of the martensite phase. The results of the tensile tests indicate that by increasing the IHT temperature, the yield and ultimate tensile strengths of the DP steel increase from 493 to 770 MPa, and from 908 to 1080 MPa, respectively, while the total elongation decreases from 9.8 to 4.5%. In contrast to the normalized sample, formation of martensite in the DP steels could eliminate the yield point phenomenon in the tensile curves, as it generates free dislocations in adjacent ferrite.

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