Organosubstituted silica derivatives were synthesized and investigated as modifiers of block copolymers based on macroinitiator and 2,4-toluene diisocyanate. A peculiarity of the modified block ...copolymers is the existence in their structure of coplanar rigid polyisocyanate blocks of acetal nature (O-polyisocyanates). Organosubstituted silica derivatives have a non-additive effect on high-temperature relaxation and α-transitions of modified polymers and exhibit the ability to influence the supramolecular structure of block copolymers. The use of the developed modifiers leads to a change in the gas transport properties of block copolymers. The increase of the permeability coefficients is due to the increase of the diffusion coefficients. At the same time, the gas solubility coefficients do not change. An increase in the ideal selectivity for a number of gas pairs is observed. An increase in the selectivity for the CO
/N
gas pair (from 25 to 39) by 1.5 times demonstrates the promising use of this material for flue gases separation.
Cytokinins (CKs) were earlier shown to promote potato tuberization. Our study aimed to identify and characterize CK-related genes which constitute CK regulatory system in the core potato (
) genome. ...For that, CK-related genes were retrieved from the sequenced genome of the
doubled monoploid (DM) Phureja group, classified and compared with Arabidopsis orthologs. Analysis of selected gene expression was performed with a transcriptome database for the
heterozygous diploid line RH89-039-16. Genes responsible for CK signaling, biosynthesis, transport, and metabolism were categorized in an organ-specific fashion. According to this database, CK receptors StHK2/3 predominate in leaves and flowers, StHK4 in roots. Among phosphotransmitters, StHP1a expression largely predominates. Surprisingly, two pseudo-phosphotransmitters intended to suppress CK effects are hardly expressed in studied organs. Among B-type
genes,
,
, and
are actively expressed, with
expressing most uniformly in all organs and
exhibiting the highest expression in roots. By cluster analysis four types of prevailing CK-signaling chains were identified in (1) leaves and flowers, StHK2/3→
1
→StRR1b/+; (2) shoot apical meristems, stolons, and mature tubers, StHK2/4→
1
→StRR1b/+; (3) stems and young tubers, StHK2/4→
1
→StRR1b/11/18a; and (4) roots and tuber sprouts, StHK4→
1
→StRR11/18a. CK synthesis genes
/
and
are expressed mainly in roots followed by tuber sprouts, but rather weakly in stolons and tubers. By contrast, CK-activation genes
are active in stolons, and
expression is even stolon-confined. Apparently, the main CK effects on tuber initiation are realized via activity of
genes in stolons. Current advances and future directions in potato research are discussed.
Chronic obstructive pulmonary disease is now one of the most common noncommunicable diseases and the main causes of morbidity, disability and mortality in the world. In recent years, new approaches ...to epidemiology, diagnosis, classification (categorization), evaluation of phenotypes, as well as characterization and assessment of the severity of сhronic obstructive pulmonary disease exacerbations have emerged. Modern approaches to starting and subsequent drug therapy have changed significantly. This is largely due to the results of recently conducted major clinical trials, demonstrated high efficacy of triple fixed combinations, including inhaled glucocorticosteroids, long-acting beta-agonists and long-acting anticholinergic drugs. The use of non-medication methods (smoking cessation, physical activity and respiratory rehabilitation) and modern approaches to the treatment of respiratory failure and antibiotic therapy remain important. In terms of their significance, all these updates have a significant impact on real clinical practice and can be considered as a novel paradigm of the approaches to the diagnosis and management of this disease.
A variety of localization and signaling properties of eight subtypes of metabotropic glutamate receptors (mGluRs) in the brain provide glutamate an important regulatory role in many processes, ...including neurodegeneration and repair of neuronal damage. To identify specific subtypes of mGluRs, which are involved in neurodegeneration process, we assessed expression levels of their genes under pathophysiological conditions. Using quantitative real-time RT-PCR analysis, we studied transcription levels of mGlu2-5 and mGlu7 genes in the hippocampus after its damage by neurotoxicant trimethyltin chloride (TMT) in Wistar rats. This organotin compound is known to cause neurodegeneration in the brain, especially in the hippocampus. Morphological studies confirmed neuronal damage in CA3-CA4 subfields of the hippocampus 6 weeks after the treatment with TMT. Step-through passive avoidance test revealed memory deterioration in rat-treated TMT. Interestingly, 3 and 6 weeks after the treatment with TMT, expression levels of the mGlu2 and mGlu7 genes were not changed in comparison to the control values while expression level of mGlu4 genes was upregulated throughout the whole studied period of TMT action. The dynamics of mGlu3 gene expression revealed the existence of neuroinflammation 3 weeks after the treatment with TMT, which was further confirmed by the upregulation of cyclooxygenase-2 gene expression. The expression level of mGlu5 receptors was downregulated 6 weeks after the treatment with TMT. Our results revealed a significant role of mGlu4, mGlu5, and mGlu3 receptors in the neurodegenerative/reparative processes in the hippocampus after the treatment with TMT. Ligands of these receptor subtypes can be, therefore, considered potential therapeutic targets for prevention or reduction of neurodegeneration.
Observational studies indicate that overutilization of inhaled corticosteroids (ICS) is common in patients with chronic obstructive pulmonary disease (COPD). Overprescription and the high risk of ...serious ICS-related adverse events make withdrawal of this treatment necessary in patients for whom the treatment-related risks outweigh the expected benefits. Elaboration of an optimal, universal, user-friendly algorithm for withdrawal of ICS therapy has been identified as an important clinical need. This article reviews the available evidence on the efficacy, risks, and indications of ICS in COPD, as well as the benefits of ICS treatment withdrawal in patients for whom its use is not recommended by current guidelines. After discussing proposed approaches to ICS withdrawal published by professional associations and individual authors, we present a new algorithm developed by consensus of an international group of experts in the field of COPD. This relatively simple algorithm is based on consideration and integrated assessment of the most relevant factors (markers) influencing decision-making, such a history of exacerbations, peripheral blood eosinophil count, presence of infection, and risk of community-acquired pneumonia.
For the holographic recording of the wave field of an object, a pattern created by the interference of the reference wave and the wave scattered by the object is used. Traditional holography requires ...mutual coherence of the reference and object-related beams. However, it has been shown in this work that the holographic recording of information concerning the object under study is possible without coherence between them, even by using radiation from different sources. Such recording can be carried out by employing subcycle or unipolar radiation pulses, when a resonant medium with a large phase memory time
T
2
is used as the recording medium. In this case, the medium records the interference pattern formed by the subcycle or unipolar pulse reflected from the object and the polarization wave created by the same short pulse. Coherence is ensured by a polarization wave, which interacting with radiation reflected from the object induces a population grating in such a medium. This grating mimics the interference pattern in a similar holographic process with a monochromatic source having the wavelength equal to that corresponding to the resonant transition in the medium.
Lagrangians of the field-theory model of a scalar field are considered as 4-forms on a Riemannian manifold. The model is constructed on the basis of the Hodge inner product, this latter being an ...analog of the scalar product of two functions. Including the basis fields in the action of the terms with tetrads makes it possible to reproduce the Klein–Gordon equation and the Maxwell equations, and also the Einstein–Hilbert action. We conjecture that the principle of construction of the Lagrangians as 4-forms can give a criterion restricting possible forms of the field-theory models.
The high prevalence of COPD in the Russian Federation has been demonstrated in several epidemiological studies. However, there are still no data on the clinical characteristics of these patients ...according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups and phenotypes, which could provide additional understanding of the burden of COPD, routine clinical practice, and ways to improve the treatment of patients with COPD in Russia.
SUPPORT was an observational multicenter study designed to obtain data about the distribution of patients with previously diagnosed COPD according to the severity of bronchial obstruction, symptom severity, risk of exacerbation, COPD phenotypes, and treatment of COPD. We included patients with a previous diagnosis of COPD who visited one of 33 primary-care centers for any reason in 23 cities in Russia.
Among the 1,505 patients with a previous diagnosis of COPD who attended the primary-care centers and were screened for the study, 1,111 had a spirometry-confirmed diagnosis and were included in the analysis. Up to 53% of the patients had severe or very severe COPD (GOLD stages III-IV), and 74.3% belonged to the GOLD D group. The majority of patients were frequent exacerbators (exacerbators with chronic bronchitis 37.3%, exacerbators without chronic bronchitis 14%), while 35.8% were nonexacerbators and 12.9% had asthma-COPD overlap. Among the GOLD D group patients, >20% were treated with only short-acting bronchodilators.
COPD is still misdiagnosed in primary care in Russia. COPD patients in primary care are usually GOLD D with frequent exacerbations and are often treated with only short-acting bronchodilators.
This paper describes the data of oxidation kinetics for metal fuels and ignition characteristics for the high-energy material (HEM) samples based on ammonium perchlorate, ammonium nitrate and an ...energetic binder, containing the powders of Al, B, AlB2, AlB12 and TiB2. The thermal oxidation of metal fuels and the thermal decomposition of the HEM samples were determined using a combined Netzsch STA 449 F3 Jupiter analyzer. The ignition of the HEM samples was studied using the radiant heating setup based on continuous CO2 laser in the heat flux density range of 90-200 W/cm2. Experimentally it was found that the complete replacement of aluminum powder by amorphous boron in the HEM sample significantly reduces the ignition delay time (by 2.2-2.8 times) in the same heat flux density. The ignition delay time of the HEM sample containing titanium diboride powder decreases slightly (by 10-25%) relative to the ignition delay time of the Al-based HEM.
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