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1.
JAMA Netw Open ; 6(2): e230050, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36763355

ABSTRACT

Importance: The conflict in Ukraine has forced civilian hospitals with limited trauma and battlefield medicine experience to care for casualties of war, placing significant strain on the health care system. Using the Checklist for Early Recognition and Treatment of Acute Illness and Injury (CERTAIN) program, a multimodal trauma critical care knowledge-exchange platform was created for clinicians practicing in these institutions. Objectives: To describe the development and implementation of the CERTAIN for Ukraine program and to evaluate the reach of this intervention, together with participant engagement and satisfaction. Design, Setting, and Participants: This quality improvement study included clinicians caring for critically ill patients during the ongoing Ukrainian conflict who were part of a community developed using a messaging app. The program was implemented by a group of international trauma and critical care experts in collaboration with critical care leaders from the Shupyk National Healthcare University in Kyiv, Ukraine. This study evaluates data collected from the CERTAIN for Ukraine program from its launch on April 9, 2022, to August 31, 2022. Interventions: The initiative comprised a longitudinal series of interactive tele-education sessions, a webpage containing the CERTAIN approach and current trauma critical care guidelines translated into Ukrainian and Russian, and a private messaging chat for asynchronous discussion. Main Outcomes and Measures: Participant engagement and satisfaction were tracked using multimedia analytics and a post-session survey. Results: Since program launch, 838 participants have joined the messaging group, and 6 tele-education sessions have been delivered, with 1835 total views. The CERTAIN website has had 3527 visits, mainly from Ukraine (1378 [39%]) and the United States (1060 [30%]). Of the 74 completed postsession surveys, 65 respondents (88%) rated the course content excellent or very good, and 73 (99%) recommended it to others. Conclusions and Relevance: The findings of this quality improvement study indicate that, using widely available and low-cost platforms, knowledge was shared rapidly and efficiently to a large community of clinicians practicing in a wartime environment with broad-based engagement and a high level of learner satisfaction.


Subject(s)
Critical Care , Hospitals , Humans , United States , Ukraine , Quality Improvement , Longitudinal Studies
2.
Int J Mol Sci ; 21(22)2020 Nov 18.
Article in English | MEDLINE | ID: mdl-33218028

ABSTRACT

Two novel coordination polymers, [Bi2(2,3pydc)2(2,3pydcH)2(H2O)]n (1) and {(Et3NH)2[Bi(2,3pydc)(2,3pydcH)Cl2]}n (2) were prepared using as a prolinker pyridine-2,3-dicarboxylic acid (2,3pydcH2). The obtained complexes were fully characterized by elemental analysis, TG/DTG, FT-IR, solid-state photoluminescence, DFT calculations and single-crystal X-ray diffraction. The obtained complexes crystallized in the triclinic P-1 space group (1) and comprise dimeric units with two crystallographically different Bi(III) centers (polyhedra: distorted pentagonal bipyramid and bicapped trigonal prism) and monoclinic P21/c space group (2) with a distorted monocapped pentagonal bipyramid of Bi(III) center. The various coordination modes of bridging carboxylate ligands are responsible for the formation of 1D chains with 4,5C10 (1) and 2C1 (2) topology. The photoluminescence quantum yield for polymer 2 is 8.36%, which makes it a good candidate for more specific studies towards Bi-based fluorescent materials. Moreover, it was detected that polymer 1 is more than twice as active against H. pylori as polymer 2. It can be concluded that there is an existing relationship between the structure and the antibacterial activity because the presence of chloride and triethylammonium ions in the structure of complex 2 reduces the antibacterial activity.


Subject(s)
Anti-Bacterial Agents , Bismuth/chemistry , Coordination Complexes , Dicarboxylic Acids/chemistry , Fluorescent Dyes , Helicobacter pylori/growth & development , Pyridines/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Fluorescent Dyes/chemistry , Fluorescent Dyes/pharmacology
3.
ChemSusChem ; 10(15): 3030-3034, 2017 08 10.
Article in English | MEDLINE | ID: mdl-28654724

ABSTRACT

Nitrogen rich carbon nanotubes have been used as a metal free catalyst for the conversion of glycerol into dihydroxyacetone using tert-butyl hydroperoxide as an oxidant. Pyridine nitrogen groups embedded in a carbon matrix are identified as active sites for the reaction. Computational studies have demonstrated that oxidation of pyridine groups to pyridine oxime followed by hydrogen abstraction from secondary alcohol is likely responsible for the oxidation process.


Subject(s)
Glycerol/chemistry , Nanotubes, Carbon/chemistry , Nitrogen/chemistry , Catalysis , Oxidation-Reduction
4.
J Phys Chem A ; 121(16): 3167-3173, 2017 Apr 27.
Article in English | MEDLINE | ID: mdl-28391687

ABSTRACT

A set of flat carbon clusters and ultrashort carbon nanotubes in different anion-radical states was investigated by density functional theory and complete-active space self-consistent field methods. It was found that carbon nanoparticles with pervasively oxidized edges are extremely strong oxidants, and their ground states in catalytic studies should be considered as negatively charged rather than neutral, as it is traditionally done. Negative charging renders initially diamagnetic/semiconducting types of carbon nanoparticles into half-metallic, which can also be achieved by doping with transition metals.

5.
Nat Commun ; 7: 12269, 2016 07 27.
Article in English | MEDLINE | ID: mdl-27461840

ABSTRACT

The need for sustainable catalysts for an efficient hydrogen evolution reaction is of significant interest for modern society. Inspired by comparable structural properties of [FeNi]-hydrogenase, here we present the natural ore pentlandite (Fe4.5Ni4.5S8) as a direct 'rock' electrode material for hydrogen evolution under acidic conditions with an overpotential of 280 mV at 10 mA cm(-2). Furthermore, it reaches a value as low as 190 mV after 96 h of electrolysis due to surface sulfur depletion, which may change the electronic structure of the catalytically active nickel-iron centres. The 'rock' material shows an unexpected catalytic activity with comparable overpotential and Tafel slope to some well-developed metallic or nanostructured catalysts. Notably, the 'rock' material offers high current densities (≤650 mA cm(-2)) without any loss in activity for approximately 170 h. The superior hydrogen evolution performance of pentlandites as 'rock' electrode labels this ore as a promising electrocatalyst for future hydrogen-based economy.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 136: 1998-2007, 2015 Feb 05.
Article in English | MEDLINE | ID: mdl-25168002

ABSTRACT

A dinuclear [Pb2(4-CHO-5-MeIm)6(NO3)2](NO3)2 (1) and a polynuclear [Pb(2-pzc)2(H2O)]n (2) complexes (where 5(4)-carbaldehyde-4(5)-methylimidazole (5(4)-CHO-4(5)-MeIm) and pyrazine-2-carboxylic acid (2-pzcH)) have been synthesized and characterized by elemental analysis, IR spectroscopy and X-ray crystallography. Structural determination for complex 1 reveals a cationic species [Pb(4-CHO-5-MeIm)3]2+ connected through bridging nitrate(V) ions. There are also an uncoordinated nitrate ions as counterions. Complex 2 is a three-dimensional architecture consisting of Pb6O12 building units. The pyrazine-2-carboxylato ligand behaves as a chelating agent and a bi-connective bridge. The coordination polyhedra around lead(II) ion could be described as a distorted docecahedron (1) or monocapped trigonal prism (2). The luminescent properties of 1 and 2 investigated in the solid state at room temperature indicate structure-dependent photoluminescent properties. The DFT calculations and the X-ray structural data point on rather hemidirected type of coordination around Pb(II) ions of 1 and 2.


Subject(s)
Chemical Phenomena , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , Lead/chemistry , Crystallography, X-Ray , Differential Thermal Analysis , Hydrogen Bonding , Ligands , Luminescence , Models, Molecular , Polymers/chemistry , Quantum Theory , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared , Thermogravimetry
7.
J Phys Chem A ; 118(34): 7052-7, 2014 Aug 28.
Article in English | MEDLINE | ID: mdl-25061852

ABSTRACT

Model carbon nanoparticles representative of the graphite-like and amorphous domains of active carbon are investigated with density functional theory (DFT) and complete active space self-consistent field (CASSCF) methods. Cyclic carbon clusters containing conjugated carbene groups are found to undergo Jahn-Teller distortion. More importantly, the half-metallicity, that is, the equal or similar stability of various spin states, previously suggested by DFT calculations for both types of nanosized clusters is confirmed by CASSCF calculations. Furthermore, the model carbon clusters are found to possess a multiconfigurational electronic structure dominated by high-spin configurations. When compared to CASSCF results, the single-reference DFT predicts proper electronic structures, characterized by antiferromagnetically coupled electron pairs, at the expense of spin contamination as a reflection of the multiconfigurational character. In fact, spin contamination, which is normally viewed as an error, does not corrupt the energetics of the half-metallic systems and therefore does not preclude the applicability of DFT to such systems.

8.
Mol Divers ; 16(3): 477-87, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22752707

ABSTRACT

Comprehensive enumeration of conformationally restricted bicyclic secondary diamines (CRDA) was performed within defined structural limits, yielding a library of all theoretically possible compounds of this class, potentially useful as building blocks for drug design. In order to assess structural diversity of the generated library, molecular geometries of the library members were optimized using DFT calculations. It was shown that the distance between the amino groups and their relative orientation in space vary widely over the whole library, which might be beneficial for diversity-oriented conformational restriction approach in drug discovery. There are many representatives of "three-dimensional" scaffolds in the CRDA library. Selected literature data on biological activity of the known CRDA derivatives were discussed, demonstrating utility of the CRDA scaffold hopping in drug design.


Subject(s)
Bridged Bicyclo Compounds/chemistry , Diamines/chemistry , Molecular Conformation , Small Molecule Libraries/chemistry
9.
Chemphyschem ; 13(12): 3018-24, 2012 Aug 27.
Article in English | MEDLINE | ID: mdl-22488957

ABSTRACT

A cobalt oxide-based oxygen-evolving cocatalyst (Co-Pi) is photodeposited by visible-light irradiation onto nanocrystalline TiO(2)-polyheptazine (TiO(2)-PH) hybrid photoelectrodes in a phosphate buffer. The Co-Pi cocatalyst couples effectively to photoholes generated in the surface polyheptazine layer of the TiO(2)-PH photoanode, as evidenced by complete photooxidation of water to oxygen under visible-light (λ>420 nm) irradiation at moderate bias potentials. In addition, the presence of the cocatalyst also reduces significantly the recombination of photogenerated charges, particularly at low bias potentials, which is ascribed to better photooxidation kinetics resulting in lower accumulation of holes. This suggests that further improvements of photoconversion efficiency can be achieved if more effective catalytic sites for water oxidation are introduced to the surface structure of the hybrid photoanodes.

10.
Dalton Trans ; 41(17): 5132-6, 2012 May 07.
Article in English | MEDLINE | ID: mdl-22450557

ABSTRACT

The reactions of N≡W(O(t)Bu)(3) with the low-coordinate phosphorus compounds (Me(3)Si)(2)NP(NSiMe(3))(2) (I) and (Me(3)Si)(2)NPS(N(t)Bu) (II) were studied. Quantum chemical calculations were used to determine why Mo- and W-containing compounds with the same composition have different molecular structures.

11.
Phys Chem Chem Phys ; 13(48): 21511-9, 2011 Dec 28.
Article in English | MEDLINE | ID: mdl-22057224

ABSTRACT

We investigated photoelectrodes based on TiO(2)-polyheptazine hybrid materials. Since both TiO(2) and polyheptazine are extremely chemically stable, these materials are highly promising candidates for fabrication of photoanodes for water photooxidation. The properties of the hybrids were experimentally determined by a careful analysis of optical absorption spectra, luminescence properties and photoelectrochemical measurements, and corroborated by quantum chemical calculations. We provide for the first time clear experimental evidence for the formation of an interfacial charge-transfer complex between polyheptazine (donor) and TiO(2) (acceptor), which is responsible for a significant red shift of absorption and photocurrent response of the hybrid as compared to both of the single components. The direct optical charge transfer from the HOMO of polyheptazine to the conduction band edge of TiO(2) gives rise to an absorption band centered at 2.3 eV (540 nm). The estimated potential of photogenerated holes (+1.7 V vs. NHE, pH 7) allows for photooxidation of water (+0.82 V vs. NHE, pH 7) as evidenced by visible light-driven (λ > 420 nm) evolution of dioxygen on hybrid electrodes modified with IrO(2) nanoparticles as a co-catalyst. The quantum-chemical simulations demonstrate that the TiO(2)-polyheptazine interface is a complex and flexible system energetically favorable for proton-transfer processes required for water oxidation. Apart from water splitting, this type of hybrid materials may also find further applications in a broader research area of solar energy conversion and photo-responsive devices.

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