PMR characterization of the water structure in tibetan milk mushroom zooglea: influence of medium hydration and hydrophobicity

The state of water in Tibetan milk mushroom zooglea with different degrees of hydration (h) was investigated using low-temperature PMR spectroscopy in air and in contact with the hydrophobic media polydimethylsiloxane PDMS-1000 and CHCl3 with added trifl uoroacetic acid (TFA). The maximum hydration of the zooglea amounted to h = 32 g/g (of dry matter). Water existed as polyassociates (clusters or domains) of strongly and weakly associated water. Bound water decomposed into clusters in the presence of TFA. The NMR spectra showed six types of bound water at h = 0.3 g/

COVID-19-associated coagulopathy in children and adolescents

The pandemic of the new coronavirus infection COVID-19 in 2020 has become the main health problem across the globe. A special characteristic of the SARSCoV-2 virus is tropism to the vascular endothelium with the  development of endotheliitis, which entails a number of typical disorders of the blood coagulation system: coagulopathy with increased thrombin generation, D-dimer, decreased fibrinolysis and prolonged prothrombin time. The coagulation disorder in COVID-19 is called thromboinflammation. Hyperinflammation, increased blood levels of von Willebrand factor, coagulation factor VIII, neutrophil extracellular traps, platelet activation, microvesicles play a significant role in the pathogenesis of hypercoagulation in COVID-19. To date, it is known that cases of COVID-19 in children and adolescents constitute a small part of the total number of patients with diagnosed COVID-19, and disorders of the blood coagulation system are similar to those in adults. The degree of hypercoagulable syndrome and the risk of thrombosis depend on the severity of COVID-19. And for children they are most expressed with the development of a hyperinflammatory immune response, called multisystem inflammatory syndrome. At the same time, clinical studies of the pathogenesis of COVID-19 in adults and children and the search for optimal methods of therapy for thrombus inflammation, which underlies the pathogenesis of COVID-19, continue

Використання ефекту мікрокоагуляції для керування зв'язуванням води у гетерогенній системі поліметилсилоксан/кремнезем/вода

The binding of water in heterogeneous systems containing polymethylsiloxane (PMS) pyrogenic nanosilica (A-300) water and the surface-active substance decametoxin (DMT) was studied. Composite systems were created using metered mechanical loads. The low-temperature 1H NMR spectroscopy was used to measure the structural and thermodynamic parameters of bound water. It is shown that when filling PMS interparticle gaps with hydrocompaction, the interfacial energy of water in the interparticle gaps of hydrophobic PMS with the same hydration is twice as large as the interfacial energy of water in hydrophilic silica A-300. This is due to the smaller linear dimensions of the interparticle gaps in the ICP compared with the A-300. In the composite system, A-300/PMS/DMT/H2O, a non-additive growth of water binding energy is observed, which is likely due to the formation, under the influence of mechanical load in the presence of water, of microheterogeneous sites, consisting mainly of the hydrophobic and hydrophilic components (microcoagulation). Thus, using mechanical loads, you can control the adsorption properties of composite systems.Вивчено зв'язування води в гетерогенних системах, що містять поліметилсилоксан, високодисперсний аморфний кремнезем, воду і поверхнево-активну речовину – декаметоксин. Композитні системи створювалися при використанні дозованих механічних навантажень. Методом низькотемпературної 1Н ЯМР-спектроскопії вимірювалися структурні і термодинамічні параметри зв'язаної води. Показано, що при заповненні міжчастинкових зазорів поліметилсилоксану способом гідроущільнення, міжфазна енергія води при однаковій гідратованості вдвічі перевищує міжфазну енергію води в гідрофільному кремнеземі. Це пов'язано з меншими лінійними розмірами міжчастинкових зазорів в поліметилсилоксані порівняно з кремнеземом. В композитній системі, кремнезем/поліметилсилоксан/декаметоксин/вода спостерігається неадитивне зростання енергії зв'язування води, яке, ймовірно, обумовлене формуванням, під впливом механічного навантаження в присутності води, мікрогетерогенних ділянок, що складаються переважно з гідрофобної і гідрофільної компонент (мікрокоагуляція). Таким чином, за допомогою механічних навантажень можна керувати адсорбційними властивостями композитних систе

PMR characterization of the water structure in tibetan milk mushroom zooglea: influence of medium hydration and hydrophobicity

The state of water in Tibetan milk mushroom zooglea with different degrees of hydration (h) was investigated using low-temperature PMR spectroscopy in air and in contact with the hydrophobic media polydimethylsiloxane PDMS-1000 and CHCl3 with added trifl uoroacetic acid (TFA). The maximum hydration of the zooglea amounted to h = 32 g/g (of dry matter). Water existed as polyassociates (clusters or domains) of strongly and weakly associated water. Bound water decomposed into clusters in the presence of TFA. The NMR spectra showed six types of bound water at h = 0.3 g/

Influence of the “wetting–drying” compaction on the adsorptive characteristics of nanosilica A-300

The methods of low-temperature 1 H NMR and IR spectroscopy, densitometry, and adsorption from solutions are applied to study the influence of “wetting–drying” compaction on the adsorptive characteristics of the nanosilica A-300 in relation to water and gelatin. It was shown that if the bulk density changes from 0.05 to 0.25 g/ml, the protein adsorptive capacity of the nanosilica decreases no more than by 30%, which, apparently, is connected with the decrease of the part of the surface, available for the protein molecules. Interfacial energy in relation to water increases from 37 to 52 mJ/m 2 if the bulk density increases and this is connected with the increase of the contribution from minor clusters (nanodrops) adsorbed on the surface water

Reversible Water-Induced Structural and Magnetic Transformations and Selective Water Adsorption Properties of Poly(manganese 1,1′-ferrocenediyl-bis(H-phosphinate))

© 2016 American Chemical Society.A flexible and hydrolytically stable metal-organic framework [Mn(H2O)2(Fc(PHOO)2)·2H2O]n has been synthesized using ferrocene-based ligand bearing phosphinic groups (Fc(PHOOH)2 = 1,1′-ferrocenediyl-bis(H-phosphinic acid)). In this compound manganese atoms are bound by phosphinate fragments to give infinite chains, and the latter are interconnected by ferrocene groups to form two-dimensional coordination polymer. The elimination of both coordinated and lattice water molecules during heating up to 150 °C produced the compound, which is nonporous for nitrogen, but can selectively adsorb water over methanol and other solvents at 298 K. The reversible structural transformation during adsorption/desorption of water is also reflected in a change of magnetic properties of the metal-organic framework