A theoretical study of 5,6,7,8-tetrahydro-6-hydroxymethylpterin: insight into intrinsic photoreceptor properties of 6-substituted tetrahydropterins

In this work, a theoretical study for platinum(II)-8-hydroxyquinolines-tetrylene complexes [{PtCl-C9H6NO}-NHEPh] (Pt-EPh) are investigated for the first time using density functional theory (DFT). Quantum chemical calculations using DFT and charge methods at the BP86 level with basic sets SVP, TZVPP have been carried out to get insight into the structures and property for Pt-EPh. The optimization of equilibrium geometries of the ligands EPh in Pt-EPh are bonded in distorted end-on way to Pt fragment with the bending angle, a, slightly decreases from carbene Pt-CPh to germylene Pt-GePh. Quantum chemical parameters such as EHOMO, ELUMO, the energy gap (ELUMO – EHOMO), electronegativity (χ), global hardness (η), and global softness (S) in the neutral molecules have been calculated and discussed. Bond dissociation energies (BDEs), De (kcal.mol-1), decrease from the slighter to the heavier homologues. The hybridization of atoms E have large p characters while the hybridization of atom Pt has greater d character which lead to the Pt-E bond possesses not only NHEPh→{ PtCl-C9H6NO} strong σ-donation but also a significant contribution π-donation NHEPh→{PtCl-C9H6NO} and a weak π-backdonation metal-ligand NHEPh←{PtCl-C9H6NO} in complexes Pt-Eph was also considered.

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A theoretical study of structure, bonding and property of platinum(II)-8-hydroxyquinolines complexes with carbene and heavier homologues

HUE UNIVERSITY JOURNAL OF SCIENCE NATURAL SCIENCE ◽

10.26459/hueuni-jns.v129i1b.5674 ◽

2020 ◽

Vol 129 (1B) ◽

pp. 41-48

Author(s):

Huynh Thi Phuong Loan ◽

Hoang Van Duc ◽

Nguyen Thi Ai Nhung

Keyword(s):

Quantum Chemical ◽

Density Functional ◽

Theoretical Study ◽

Energy Gap ◽

Functional Theory ◽

Dissociation Energies ◽

The Density Functional Theory ◽

First Time ◽

Equilibrium Geometries ◽

Insight Into

In this work, a theoretical study for platinum(II)-8-hydroxyquinoline-tetrylene complexes [{PtCl–C9H6NO}–NHEPh] (Pt–EPh) is carried out for the first time by using the density functional theory (DFT). Quantum chemical calculations with DFT and charge methods at the BP86 level with basic sets SVP and TZVPP have been perfomed to get insight into the structures and property of Pt–EPh. The optimization of equilibrium geometries of the ligands EPh in Pt–EPh, bonded in the distorted end-on way to the Pt fragment is studied, in which the bending angle slightly decreases from carbene Pt–CPh to germylene Pt–GePh. Quantum chemical parameters such as EHOMO, ELUMO, the energy gap (ELUMO – EHOMO), electronegativity, global hardness, and global softness in the neutral molecules have been calculated and discussed. Bond dissociation energies decrease from the slighter to the heavier homologues. The hybridization of atoms E has large p characters, while the hybridization of atom Pt has a greater d character. Thus, the Pt–E bond possesses not only NHEPh→{PtCl–C9H6NO} strong -donation but also a significant contribution of π-donation NHEPh→{PtCl–C9H6NO}, and a weak π-backdonation metal-ligand NHEPh←{PtCl-C9H6NO} in complexes Pt-EPh is also considered.

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Aleksey Peshkov as an editor of Samarskaya Gazeta

Voprosy literatury ◽

10.31425/0042-8795-2020-4-128-138 ◽

2020 ◽

pp. 128-138

Author(s):

A. S. Bik-Bulatov

Keyword(s):

Local History ◽

Organizational Skills ◽

First Time ◽

New Evidence ◽

Insight Into ◽

Shed Light

The article uses little known letters of M. Gorky, many of which were published for the first time in 1997, as well as findings of Samara-based experts in local history to shed light on the writer’s work as editor-in-chief of the Samarskaya Gazeta newspaper in 1895. The researcher introduces hitherto unstudied reminiscences of the journalist D. Linyov (Dalin) about this period, which reference a letter by Gorky, now lost. The paper details a newly discovered episode of Gorky’s professional biography as a journalist: it concerns his campaign against a Samara ‘she-wolf,’ the madam of a local brothel A. Neucheva. Linyov’s reminiscences turn out to be an important and interesting source, offering an insight into the daily grind of the young editor Gorky, providing new evidence of his excellent organizational skills, and describing his moral and social stance. The author presents his work in the context of a recently initiated broader discussion about the need to map out all Russian periodicals for the period until 1917, as well as all research devoted to individual publications.

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Comparative Study of Chemical Compositions and Antioxidant Capacities of Oils Obtained from 15 Macadamia (Macadamia integrifolia) Cultivars in China

Foods ◽

10.3390/foods10051031 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1031

Author(s):

Xixiang Shuai ◽

Taotao Dai ◽

Mingshun Chen ◽

Ruihong Liang ◽

Liqing Du ◽

...

Keyword(s):

Palmitoleic Acid ◽

Linear Regression Analysis ◽

Monounsaturated Fatty Acids ◽

Multiple Linear Regression Analysis ◽

Chemical Compositions ◽

Macadamia Integrifolia ◽

Antioxidant Capacities ◽

Squalene Content ◽

First Time ◽

Insight Into

The planting area of macadamia in China accounted for more than one third of the world’s planted area. The lipid compositions, minor components, and antioxidant capacities of fifteen varieties of macadamia oil (MO) in China were comparatively investigated. All varieties of MO were rich in monounsaturated fatty acids, mainly including oleic acid (61.74–66.47%) and palmitoleic acid (13.22–17.63%). The main triacylglycerols of MO were first time reported, including 19.2–26.1% of triolein, 16.4–18.2% of 1-palmitoyl-2,3-dioleoyl-glycerol, and 11.9–13.7% of 1-palmitoleoyl-2-oleoyl-3-stearoyl-glycerol, etc. The polyphenol, α-tocotrienol and squalene content varied among the cultivars, while Fuji (791) contained the highest polyphenols and squalene content. Multiple linear regression analysis indicated the polyphenols and squalene content positively correlated with the antioxidant capacity. This study can provide a crucial directive for the breeding of macadamia and offer an insight into industrial application of MO in China.

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ASKAP observations of multiple rapid scintillators reveal a degrees-long plasma filament

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab139 ◽

2021 ◽

Vol 502 (3) ◽

pp. 3294-3311

Author(s):

Yuanming Wang ◽

Artem Tuntsov ◽

Tara Murphy ◽

Emil Lenc ◽

Mark Walker ◽

...

Keyword(s):

Physical Properties ◽

Angular Width ◽

Scattering Medium ◽

Central Frequency ◽

Linear Arrangement ◽

Plasma Filament ◽

Kinematic Models ◽

Tidal Stream ◽

First Time ◽

Insight Into

ABSTRACT We present the results from an Australian Square Kilometre Array Pathfinder search for radio variables on timescales of hours. We conducted an untargeted search over a 30 deg2 field, with multiple 10-h observations separated by days to months, at a central frequency of 945 MHz. We discovered six rapid scintillators from 15-min model-subtracted images with sensitivity of $\sim\! 200\, \mu$Jy/beam; two of them are extreme intra-hour variables with modulation indices up to $\sim 40{{\ \rm per\ cent}}$ and timescales as short as tens of minutes. Five of the variables are in a linear arrangement on the sky with angular width ∼1 arcmin and length ∼2 degrees, revealing the existence of a huge plasma filament in front of them. We derived kinematic models of this plasma from the annual modulation of the scintillation rate of our sources, and we estimated its likely physical properties: a distance of ∼4 pc and length of ∼0.1 pc. The characteristics we observe for the scattering screen are incompatible with published suggestions for the origin of intra-hour variability leading us to propose a new picture in which the underlying phenomenon is a cold tidal stream. This is the first time that multiple scintillators have been detected behind the same plasma screen, giving direct insight into the geometry of the scattering medium responsible for enhanced scintillation.

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Rapid systemic surge of IL-33 after severe human trauma: a prospective observational study

Molecular Medicine ◽

10.1186/s10020-021-00288-1 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Olav Sundnes ◽

William Ottestad ◽

Camilla Schjalm ◽

Peter Lundbäck ◽

Lars la Cour Poulsen ◽

...

Keyword(s):

High Resolution ◽

Prospective Observational Study ◽

Tissue Injury ◽

Trauma Patients ◽

Decoy Receptor ◽

Interleukin 33 ◽

Injured Patients ◽

First Time ◽

Kinetics Of ◽

Insight Into

Abstract Background Alarmins are considered proximal mediators of the immune response after tissue injury. Understanding their biology could pave the way for development of new therapeutic targets and biomarkers in human disease, including multiple trauma. In this study we explored high-resolution concentration kinetics of the alarmin interleukin-33 (IL-33) early after human trauma. Methods Plasma samples were serially collected from 136 trauma patients immediately after hospital admission, 2, 4, 6, and 8 h thereafter, and every morning in the ICU. Levels of IL-33 and its decoy receptor sST2 were measured by immunoassays. Results We observed a rapid and transient surge of IL-33 in a subset of critically injured patients. These patients had more widespread tissue injuries and a greater degree of early coagulopathy. IL-33 half-life (t1/2) was 1.4 h (95% CI 1.2–1.6). sST2 displayed a distinctly different pattern with low initial levels but massive increase at later time points. Conclusions We describe for the first time early high-resolution IL-33 concentration kinetics in individual patients after trauma and correlate systemic IL-33 release to clinical data. These findings provide insight into a potentially important axis of danger signaling in humans.

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An insight into the dual fluorescence of 3,6-dihydroxybenzene-1,2,4,5-tetracarboxylic acid tetraethyl ester – An experimental and theoretical study

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2021.119496 ◽

2021 ◽

Vol 252 ◽

pp. 119496

Author(s):

L.B. Aswathy ◽

Ani Deepthi ◽

E.G. Jayasree

Keyword(s):

Theoretical Study ◽

Tetracarboxylic Acid ◽

Dual Fluorescence ◽

Insight Into

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Insight into the Secondary Metabolites of Geum urbanum L. and Geum rivale L. Seeds (Rosaceae)

Plants ◽

10.3390/plants10061219 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1219

Author(s):

Marek Bunse ◽

Peter Lorenz ◽

Florian C. Stintzing ◽

Dietmar R. Kammerer

Keyword(s):

Fatty Acids ◽

Phenolic Compounds ◽

Unsaturated Fatty Acids ◽

Asiatic Acid ◽

Cosmetic Products ◽

Nutritional Properties ◽

First Time ◽

Derivatives Of ◽

Geum Urbanum ◽

Insight Into

The present study aimed at the identification and quantitation of phenolic compounds, fatty acids, and further characteristic substances in the seeds of Geum urbanum L. and Geum rivale L. For this purpose, individual components of extracts recovered with MeOH, CH2Cl2, and by cold-pressing, respectively, were characterized by HPLC-DAD/ESI-MSn and GC/MS and compared with reference compounds. For both Geum species, phenolic compounds, such as flavonoids and gallic acid derivatives, and triterpenes, such as saponins and their aglycones, were detected. Surprisingly, both Geum species revealed the presence of derivatives of the triterpenoid aglycons asiatic acid and madecassic acid, which were characterized for the first time in the genus Geum. Furthermore, the fatty acids of both species were characterized by GC–MS after derivatization. Both species showed a promising fatty-acid profile in terms of nutritional properties because of high proportions of unsaturated fatty acids. Linoleic acid and linolenic acid were most abundant, among other compounds such as palmitic acid and stearic acid. In summary, the present study demonstrates the seeds of G. urbanum and G. rivale to be a valuable source of unsaturated fatty acids and bioactive phenolics, which might be exploited for nutritional and cosmetic products and for phytotherapeutic purposes.

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Theoretical study of the pyrolysis of β-1,4-xylan: a detailed investigation on unimolecular concerted reactions

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06024k ◽

2021 ◽

Vol 23 (4) ◽

pp. 2605-2621

Author(s):

M. Goussougli ◽

B. Sirjean ◽

P.-A. Glaude ◽

R. Fournet

Keyword(s):

Thermal Decomposition ◽

Theoretical Study ◽

First Time

A theoretical study of the thermal decomposition of β-1,4-xylan, a model polymer of hemicelluloses, is proposed for the first time.

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