2,024 research outputs found
Syntaxonomy of chalk outcrop vegetation of the order Thymo cretacei-Hyssopetalia cretacei
The order Thymo cretacei-Hyssopetalia cretacei Didukh 1989 combines chalk outcrop plant communities of the southwestern Central Russian Upland. Its specificity can be attributed to a rather peculiar and heterogeneous flora with a large number of endemic species. The question about its origin has caused a lively discussion, which has been going on since the late nineteenth century. Since 1989 works on the classification of these communities have frequently been carried out, but until today no unanimous decision could be reached. The purpose of our research was to conduct a critical analysis of the syntaxonomical structure of Cretaceous outcrop vegetation and to show its difference from the steppe vegetation of the class Festuco-Brometea Br.-Bl. et Tx. ex Soó 1947. The territory of our research covers the southwestern foothills of the Central Russian Upland and the Donetsk Range, located only within the steppe zone and characterised by Cenomanian chalk outcrops. In total 354 relevés were used for the analysis. The modified TWINSPAN classification was used for the analysis. Our research has shown that the order Thymo cretacei-Hyssopetalia cretacei includes twelve associations belonging to three alliances: Artemisio hololeucae-Hyssopion cretacei Romashchenko et al. 1996, Euphorbio cretophilae-Thymion cretacei Didukh 1989 and Centaureo carbonatae-Koelerion talievii Romashchenko et al. 1996
Comparative Study of the Mucoadhesive Properties of Polymers for Pharmaceutical Use
BACKGROUND: In recent years, mucoadhesive dosage forms due to their advantages have attracted the interest of researchers and developers. Polymeric excipients are included into the drug composition to give adhesion to the mucous membrane.
AIM: The aim of this research was to select a specific brand of pharmaceutical quality polymer that is promising for inclusion in the drug formulation.
METHODS: The article presents the results of studying the mucoadhesive properties of polymers on two models using mucin: By measuring the amount of adhesion and by the evaluation the sample movement speed.
RESULTS: According to the combination of two indicators, the highest mucoadhesive properties were shown by the brands of hydroxypropylmethylcellulose and xanthan gum. In addition, it was noted that hydroxyethylcellulose (HEC), sodium alginate, and hydroxypropylmethylcellulose (HPMC) also have good mucoadhesive properties. Polyethylene glycols proved to have the weakest mucoadhesive properties. The negative relationship between the average molecular weight and the sample movement speed of the HEC and HPMC was established. Obtained data showed no direct influence of the polymer average molecular weight on the amount of adhesion. It was also noted that there is no strong correlation between the amount of adhesion and the sample movement speed of the experimental samples.
CONCLUSION: Based on the results of the study, it was suggested that the complex influences of the physical and chemical properties of the polymer on its mucoadhesive properties
Developing the accounting concept in the public sector
The main goal of this study is to develop an accounting concept for the public administration sector of the Russian Federation with state (municipal) institutions as an example. To fulfill this task, the specifics of the state (municipal) institutions were explored, the international practice of arranging accounting in the public sector was analyzed, and the current state of the information and administration function of accounting in the institutions under study was examined. Because of the analysis, specific proposals for the development of the information function of accounting were developed through the application of the accounting policy template and the development of management accounting for obtaining information for internal users. Regarding the development of the control function of accounting in state (municipal) institutions, the use of a risk map, a register of risks and other administration tools and procedures was justified. The scientific novelty of the study is in systematization of the problems existing in the formation of the accounting system in state (municipal) institutions and in the development of proposals to improve its efficiency.peer-reviewe
Finding of the Low Molecular Weight Inhibitors of Resuscitation Promoting Factor Enzymatic and Resuscitation Activity
Background: Resuscitation promoting factors (RPF) are secreted proteins involved in reactivation of dormant actinobacteria, including Mycobacterium tuberculosis. They have been considered as prospective targets for the development of new antituberculosis drugs preventing reactivation of dormant tubercle bacilli, generally associated with latent tuberculosis. However, no inhibitors of Rpf activity have been reported so far. The goal of this study was to find low molecular weight compounds inhibiting the enzymatic and biological activities of Rpfs. Methodology/Principal Findings: Here we describe a novel class of 2-nitrophenylthiocyanates (NPT) compounds that inhibit muralytic activity of Rpfs with IC50 1–7 mg/ml. Fluorescence studies revealed interaction of active NPTs with the internal regions of the Rpf molecule. Candidate inhibitors of Rpf enzymatic activity showed a bacteriostatic effect on growth of Micrococcus luteus (in which Rpf is essential for growth protein) at concentrations close to IC50. The candidate compounds suppressed resuscitation of dormant (‘‘non-culturable’’) cells of M. smegmatis at 1 mg/ml or delayed resuscitation of dormant M. tuberculosis obtained in laboratory conditions at 10 mg/ml. However, they did not inhibit growth of active mycobacteria under these concentrations. Conclusions/Significance: NPT are the first example of low molecular weight compounds that inhibit the enzymatic an
Lake and Sea Populations of Mysis relicta (Crustacea, Mysida) with Different Visual-Pigment Absorbance Spectra Use the Same A1 Chromophore
Peer reviewe
Formalized classification of semi-dry grasslands in central and eastern Europe
European semi-dry grasslands are among the most species-rich vegetation types in the northern hemisphere and form an important part of the habitat mosaics in the forest-steppe zone. However. there is no comprehensive evaluation of the variation in their composition and the phytosocio-logical classification of these grasslands. For the syntaxonomic revision, we used a dataset of 34,173 vegetation plot records (releves) from central and eastern Europe. which were assigned to the class Fesiuco-Bromeiea using the diagnostic species listed in the EuroVegChecklist. To determine the diagnostic species of the orders, we used a TWINSPAN classification of the whole dataset. Of the total dataset, 15,449 releves were assigned to the order Brachypodietalia pinnati. which corresponds to semi-dry grasslands. This subset was again classified using TWINSPAN. Formal definitions of the following alliances were established: Mesobromion erecti, Cirsio-Brachypodion pinnati (incl. Fragario-Trifolion montani. Agrosiio-Avenulion schellianae, Scabioso ochroleucae-Poion angustifoliae and Adonido vernalis-Stipion iirsae), Scorzonerion villosae and Chrysopogono-Danshonion. Another alliance, Armerion elongatae (=Koelerio-Phleion phleoidis p.p.). is transitional towards the class Koelerio-Corynephoreiea and its status needs further evaluation. We also established formal definitions of all of the associations of Mesobromion and Cirsio-Brachypodion within the area studied. Associations were identified using (i) a TWINSPAN classification of the whole order, (ii) TWINSPAN classifications of regionally restricted data sets (usually all Brachypodietalia plots in one country) and (iii) existing national classification schemes. All formal definitions were written in the expert system language of the JUICE program. To obtain a more complete picture of the floristic similarities and gradients. we performed a DCA ordination of the associations. Our results revealed that meadow steppes in the forest-steppe zone in eastern Europe are very similar to semi-dry grasslands in central Europe
Роль иммунных механизмов в формировании аутоиммунной овариальной недостаточности при кистах яичников
Проведено исследование иммунологического статуса у пациенток с кистами яичников и аутоиммунной овариальной недостаточностью при хронических воспалительных заболеваниях органов малого таза (ХВЗОТ). Полученные данные могут быть использованы для оценки степени повреждения яичников при ХВЗОТ и определение эффективности лечебных мероприятий.Проведено дослідження імунологічного статусу у пацієнток з кистами яєчників і аутоімунною оваріальною недостатністю при хронічних запальних захворюваннях органів малого таза (ХЗЗОТ). Отримані дані можуть бути використані для оцінки ступеня ушкодження яєчників при ХЗЗОТ і визначення ефективності
лікувальних заходів.Research of the immunologic status at patients with cysts of ovaries and utoimmune ovarian insufficiency is carried out at chronic inflammatory diseases of organs a small pelvis (CIDОP). The obtained data can be used for an assessment of a damage rate of an ovary at CIDОP and definitions of effectiveness of medical actions
EUNIS Habitat Classification: Expert system, characteristic species combinations and distribution maps of European habitats
Aim: The EUNIS Habitat Classification is a widely used reference framework for European habitat types (habitats), but it lacks formal definitions of individual habitats that would enable their unequivocal identification. Our goal was to develop a tool for assigning vegetation‐plot records to the habitats of the EUNIS system, use it to classify a European vegetation‐plot database, and compile statistically‐derived characteristic species combinations and distribution maps for these habitats. Location: Europe. Methods: We developed the classification expert system EUNIS‐ESy, which contains definitions of individual EUNIS habitats based on their species composition and geographic location. Each habitat was formally defined as a formula in a computer language combining algebraic and set‐theoretic concepts with formal logical operators. We applied this expert system to classify 1,261,373 vegetation plots from the European Vegetation Archive (EVA) and other databases. Then we determined diagnostic, constant and dominant species for each habitat by calculating species‐to‐habitat fidelity and constancy (occurrence frequency) in the classified data set. Finally, we mapped the plot locations for each habitat. Results: Formal definitions were developed for 199 habitats at Level 3 of the EUNIS hierarchy, including 25 coastal, 18 wetland, 55 grassland, 43 shrubland, 46 forest and 12 man‐made habitats. The expert system classified 1,125,121 vegetation plots to these habitat groups and 73,188 to other habitats, while 63,064 plots remained unclassified or were classified to more than one habitat. Data on each habitat were summarized in factsheets containing habitat description, distribution map, corresponding syntaxa and characteristic species combination. Conclusions: EUNIS habitats were characterized for the first time in terms of their species composition and distribution, based on a classification of a European database of vegetation plots using the newly developed electronic expert system EUNIS‐ESy. The data provided and the expert system have considerable potential for future use in European nature conservation planning, monitoring and assessment
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is . The combined inclusive and differential asymmetries are consistent with recent standard model predictions
Derivatives of 9-phosphorylated acridine as butyrylcholinesterase inhibitors with antioxidant activity and the ability to inhibit β-amyloid self-aggregation: potential therapeutic agents for Alzheimer’s disease
We investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosphorylacridines against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CES). We also studied the abilities of the new compounds to interfere with the self-aggregation of β-amyloid (Aβ42) in the thioflavin test as well as their antioxidant activities in the ABTS and FRAP assays. We used molecular docking, molecular dynamics simulations, and quantum-chemical calculations to explain experimental results. All new compounds weakly inhibited AChE and off-target CES. Dihydroacridines with aryl substituents in the phosphoryl moiety inhibited BChE; the most active were the dibenzyloxy derivative 1d and its diphenethyl bioisostere 1e (IC50 = 2.90 ± 0.23 µM and 3.22 ± 0.25 µM, respectively). Only one acridine, 2d, an analog of dihydroacridine, 1d, was an effective BChE inhibitor (IC50 = 6.90 ± 0.55 μM), consistent with docking results. Dihydroacridines inhibited Aβ42 self-aggregation; 1d and 1e were the most active (58.9% ± 4.7% and 46.9% ± 4.2%, respectively). All dihydroacridines 1 demonstrated high ABTS•+-scavenging and iron-reducing activities comparable to Trolox, but acridines 2 were almost inactive. Observed features were well explained by quantum-chemical calculations. ADMET parameters calculated for all compounds predicted favorable intestinal absorption, good blood–brain barrier permeability, and low cardiac toxicity. Overall, the best results were obtained for two dihydroacridine derivatives 1d and 1e with dibenzyloxy and diphenethyl substituents in the phosphoryl moiety. These compounds displayed high inhibition of BChE activity and Aβ42 self-aggregation, high antioxidant activity, and favorable predicted ADMET profiles. Therefore, we consider 1d and 1e as lead compounds for further in-depth studies as potential anti-AD preparations
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