139 research outputs found
Atomic force microscopy in the modelâs development of polymeric functional materials formation on inert supports
This work was supported by the RFBR (project No. 18-08-01356 A)
Synthesis of Decorated Carbon Structures with Encapsulated Components by Low-Voltage Electric Discharge Treatment
Abstract: Polycondensation of complexes of chloromethanes with triphenylphosphine by the action of low-voltage electric discharges in the liquid phase gives nanosized solid products. The elemental composition involving the generation of element distribution maps (scanning electron microscopyâenergy dispersive Xâray spectroscopy mapping) and the component composition (by direct evolved gas analysisâmass spectrometry) of the solid products have been studied. The elemental and component compositions of the result-ing structures vary widely depending on the chlorine content in the substrate and on the amount of triphenylphosphine taken. Thermal desorption analysis revealed abnormal behavior of HCl and benzene present in the solid products. In thermal desorption spectra, these components appear at an uncharacteristically high temperature. The observed anomaly in the behavior of HCl is due to HCl binding into a complex of the solid anion HCI-2 with triphenyl(chloromethyl)phosphonium chloride, which requires a relatively high temperature (up to 800 K) to decompose. The abnormal behavior of benzene is associated with its encapsulated state in nanostructures. The appearance of benzene begins at 650 K and continues up to temperatures above 1300 K. © 2022, The Author(s).The work was carried out with the equipment of the "Modern Nanotechnologies" Ural Shared-Use Center at the Ural Federal University. The study was supported by the Russian Foundation for Basic Research, project no. 18-29-24008
Long-range intramolecular electron transfer in aromatic radical anions and binuclear transition metal complexes
Synthesis and properties of novel polyurethanes based on amino ethers of boric acid for gas separation membranes
© The Royal Society of Chemistry. Herein we present the structural and mechanical properties of polyurethanes synthesized from amino ethers of boric acid for gas separation. The polymers were characterized by light scattering methods, conductivity measurements, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and atomic force microscopy. Additionally, the permeability of ammonia and carbon dioxide, as well as the selectivity for their diffusion and resultant impurity are presented. The results illustrate the steric hindrance, resulting in a branched architecture borate formation, leads to intermolecular complexation which may assist the polymer in ammonia diffusion selectivity
The method of vascular anastomosis formation
Đ Đ°Đ·ŃĐ°Đ±ĐŸŃĐ°Đœ ĐŒĐ”ŃĐŸĐŽ ĐœĐ°Đ»ĐŸĐ¶Đ”ĐœĐžŃ ŃĐŸŃŃĐŽĐžŃŃĐŸĐłĐŸ Đ°ĐœĐ°ŃŃĐŸĐŒĐŸĐ·Đ°, ĐżŃĐ”ĐžĐŒŃŃĐ”ŃŃĐČĐŸĐŒ ĐșĐŸŃĐŸŃĐŸĐłĐŸ ŃĐČĐ»ŃĐ”ŃŃŃ ŃĐŸ, ŃŃĐŸ Đ°ĐœĐ°ŃŃĐŸĐŒĐŸĐ· ŃĐŸŃĐŒĐžŃŃŃŃ ĐœĐ° ĐœĐžŃĐžĐœĐŸĐ»ĐŸĐČĐŸĐŒ ĐșĐ°ŃĐșĐ°ŃĐ” ĐČ ĐČОЎД ĐœĐžŃĐžĐœĐŸĐ»ĐŸĐČĐŸĐč ŃпОŃалО ĐŽĐžĐ°ĐŒĐ”ŃŃĐŸĐŒ 0,1 ĐŒĐŒ. ĐĐŸ ĐŽĐ°ĐœĐœŃĐŒ ĐœĐ°Đ±Đ»ŃĐŽĐ”ĐœĐžŃ Đ·Đ° паŃĐžĐ”ĐœŃĐ°ĐŒĐž ĐČ ŃŃĐŸĐșĐž ĐŸŃ 5 ĐŽĐŸ 12 ĐŒĐ”Ń ĐŸŃĐŒĐ”ŃĐ”ĐœĐ° ĐŸŃлОŃĐœĐ°Ń ĐżŃĐŸŃ
ĐŸĐŽĐžĐŒĐŸŃŃŃ ŃĐŸŃŃĐŽĐžŃŃŃŃ
Đ°ĐœĐ°ŃŃĐŸĐŒĐŸĐ·ĐŸĐČ, ĐșŃĐŸĐČĐŸŃĐŸĐș ĐČ Đ·ĐŸĐœĐ” Đ°ĐœĐ°ŃŃĐŸĐŒĐŸĐ·Đ° ĐżĐŸĐ»ĐœĐŸŃŃŃŃ ĐșĐŸĐŒĐżĐ”ĐœŃĐžŃĐŸĐČĐ°Đœ, ŃŃĐŸ ĐżĐŸĐŽŃĐČĐ”ŃĐ¶ĐŽĐ”ĐœĐŸ ĐŽĐ°ĐœĐœŃĐŒĐž ĐŽŃплДĐșŃĐœĐŸĐłĐŸ ŃĐșĐ°ĐœĐžŃĐŸĐČĐ°ĐœĐžŃ. ĐŃĐżĐŸĐ»ŃĐ·ĐŸĐČĐ°ĐœĐžĐ” ĐżŃĐ”ĐŽĐ»ĐŸĐ¶Đ”ĐœĐœĐŸĐłĐŸ ĐŒĐ”ŃĐŸĐŽĐ° ĐżĐŸĐ·ĐČĐŸĐ»ĐžĐ»ĐŸ Đ·ĐœĐ°ŃĐžŃДлŃĐœĐŸ ŃĐŒĐ”ĐœŃŃĐžŃŃ ŃĐ°ŃŃĐŸŃŃ ĐżĐŸŃĐ»Đ”ĐŸĐżĐ”ŃĐ°ŃĐžĐŸĐœĐœŃŃ
ĐŸŃĐ»ĐŸĐ¶ĐœĐ”ĐœĐžĐč, ŃĐŒĐ”ĐœŃŃĐžŃŃ ĐżŃĐŸĐŽĐŸĐ»Đ¶ĐžŃДлŃĐœĐŸŃŃŃ ĐœĐ°Đ»ĐŸĐ¶Đ”ĐœĐžŃ Đ°ĐœĐ°ŃŃĐŸĐŒĐŸĐ·Đ°, ОзбДжаŃŃ ŃŃĐ”ĐœĐŸĐ·ĐžŃĐŸĐČĐ°ĐœĐžŃ ŃĐŸŃŃĐŽĐ°.The method of vascular anastomosis formation was elaborated. Formation of the anastomosis on the spiral nitinol carcass, consisting of a diameter 0.1 mm nitinol thread, constitutes its advantage. An excellent passability of vascular anastomoses, the compensated blood flow in anastomotic area were noted, according to the patients followâup duplex scanning data in terms from 5 to 12 months. Application of the method proposed have permitted to reduce significantly postoperative morbidity, to shorten duration of the anastomosis formation and to prevent vascular stenosis
Linear response in theory of electron transfer reactions as an alternative to the molecular harmonic oscillator model
The surface morphology effect of non-porous polymeric membranes on their gas separation properties
ĐĐ”ŃĐŸĐŽĐŸĐŒ Đ°ŃĐŸĐŒĐœĐŸ-ŃĐžĐ»ĐŸĐČĐŸĐč ĐŒĐžĐșŃĐŸŃĐșĐŸĐżĐžĐž ĐČ ŃĐŸŃĐ”ŃĐ°ĐœĐžĐž Ń ĐŒĐ”ŃĐŸĐŽĐŸĐŒ ĐĐ°ĐčĐœĐ”ŃĐ°-ĐĐ°ŃŃĐ”ŃĐ° ОзŃŃĐ”ĐœŃ ĐœĐ”ĐżĐŸŃĐžŃŃŃĐ” ĐżĐŸĐ»ĐžĐ°ĐŒĐžĐŽĐœŃĐ” ĐŒĐ”ĐŒĐ±ŃĐ°ĐœŃ Ń ŃазлОŃĐœĐŸĐč ŃĐ”ŃĐŸŃ
ĐŸĐČĐ°ŃĐŸŃŃŃŃ. ĐŃĐŸĐČĐ”ĐŽĐ”Đœ ŃŃĐ°ĐČĐœĐžŃДлŃĐœŃĐč Đ°ĐœĐ°Đ»ĐžĐ· ĐżĐŸĐ»ŃŃĐ”ĐœĐœŃŃ
ŃДзŃĐ»ŃŃĐ°ŃĐŸĐČ. ĐĐŸĐșĐ°Đ·Đ°ĐœĐ° ĐșĐŸŃŃДлŃŃĐžŃ ŃĐŸĐżĐŸĐłŃĐ°ŃОО ĐżĐŸĐČĐ”ŃŃ
ĐœĐŸŃŃĐž ОзŃŃĐ”ĐœĐœŃŃ
ĐŒĐ”ĐŒĐ±ŃĐ°Đœ Ń ĐžŃ
ĐłĐ°Đ·ĐŸŃазЎДлОŃДлŃĐœŃĐŒĐž ŃĐČĐŸĐčŃŃĐČĐ°ĐŒĐž.The surface morphology of non-porous polyamide membranes with a different roughness was studied by atomic-force microscopy with combined the Daynes-Barrer method. The comparative analysis of obtained results is carried out. The correlation of the surface topography of studied membranes with their gas separation properties is shown.Đ Đ°Đ±ĐŸŃĐ° ĐČŃĐżĐŸĐ»ĐœĐ”ĐœĐ° ĐżŃĐž ŃĐžĐœĐ°ĐœŃĐŸĐČĐŸĐč ĐżĐŸĐŽĐŽĐ”ŃжĐșĐ” Đ ĐŸŃŃĐžĐčŃĐșĐŸĐłĐŸ ĐœĐ°ŃŃĐœĐŸĐłĐŸ ŃĐŸĐœĐŽĐ° ĐČ ŃĐ°ĐŒĐșĐ°Ń
ĐżŃĐŸĐ”ĐșŃĐ° â 15-19-10057
The use of thromboelastography and the functional tests with double local hypoxia of the upper limb to assess the risk of thromboembolism in patients undergoing surgery
Introduction: Prothrombotic is considered a condition that leads to the development of venous or arterial thrombosis and its consequences. There are many factors that cause a violation of the hemostatic potential in patients undergoing surgery with existing risk factors for thromboembolism, a more detailed study of the blood coagulation system, including the study of the compensatory capabilities of the hemocoagulation system, should be conducted. One of these methods is a functional test with double local hypoxia of the upper limb (DLHUL) under the control of thromboelastography (TEG).
Goals: The purpose of the study - to identify the degree of thrombotic risk in patients preparing for planned surgical intervention, who belong to the risk group of thrombotic complications, to compare and evaluate the state of the hemostasis system in healthy volunteers and in this cohort of patients using a functional test with double local hypoxia of the upper limb by the method of thromboelastography.
Materials and methods: A randomized prospective study was conducted. Patients were divided into two groups depending on the presence of risk factors for thrombosis. Group 1 consisted of healthy volunteers (n = 40) who are not at risk of thrombosis. Group 2 includes patients with existing factors of thrombotic risk (n = 120) who are preparing for scheduled surgical interventions. These patients underwent a functional test of "double local hypoxia of the upper limb" (DLHUL) using thromboelastographic (TEG) methods of studying the hemocoagulation system. The main task of this functional test is to create a trigger component to determine the limits of hemostasis, the origin and duration of adaptive and compensatory reactions of the hemostasis system. Indicators of the hemostasis system are recorded using a thromboelastograph before and after the test. The links of hemostasis are reflected by the following indicators: aggregate state of blood (A0), contact coagulation intensity (CCI), coagulation drive intensity (ICD), maximum clot density - maximum activity (MA), fibrinolytic activity - clot retraction and lysis index (IRCL).
The results. Analyzing the data of thromboelastography after performing DLHUL, among the patients of Group 1, two types of reaction of the hemostasis system were found in patients without predictors of thrombotic risk: compensated (n= 20) (characterized by a decrease in the indicators of the vascular-platelet component; subcompensated (n = 20) (characterized by an increase in the indicators of the vascular -platelet component). In subjects of Group 1, TEG indicators indicate an increase in the external mechanism of prothrombinase formation, and the reaction of the procoagulant link of the blood coagulation system in response to the influence of a trigger indicates a change in the directionality of the hemostatic potential towards hypercoagulation. In subjects of group 1 with a compensated type, there is an increase in the components of fibrinolysis and a deviation of the hemostatic potential towards hypocoagulation is observed. The state of the hemostasis system in patients of Group 2 is characterized by pronounced changes in the hemostatic potential in all links. In the vascular-platelet link, a violation of platelet aggregation was noted, with an increase in indicators in response to a stimulus. When conducting the DLHUL test in the subjects of group 2, a decompensated (n = 98) and exhausted (n = 22) type of reaction to the test with local hypoxia of the upper limb was determined. That is, with increased platelet aggregation, hypercoagulation, inhibition of the anticoagulant system and fibrinolysis before the action of the trigger factor, after performing the DLHUL test, these disorders in the hemostasis system progress towards hypercoagulation, which is indicated by the increase in platelet aggregation, the strengthening of the coagulation link of the hemostatic system, the depression of fibrinolysis increases . However, the intensity of these changes is not as high as in patients of group 1 after the DLHUL test.
Conclusions: The test with double local hypoxia of the upper limb is effective as a trigger factor to determine the compensatory capabilities of the HS. Depending on the type of reaction of the platelet-vascular, coagulation components of hemostasis and fibrinolysis to the influence of the trigger, two types of reaction of the blood aggregate state regulation system are possible in people who do not have an anamnesis of factors provoking a hypercoagulable state: compensated and subcompensated. Therefore, when planning surgical intervention in this cohort of patients, the risk of thrombotic complications is low. Depending on the type of reaction of the platelet-vascular, coagulation components of hemostasis and fibrinolysis to the influence of the trigger, two types of reaction of the blood aggregate state regulation system are possible in people with an anamnesis of factors provoking a hypercoagulable state: decompensated (more often) and depleted (less often). Patients with a history of factors provoking a hypercoagulable state have a high risk of perioperative thrombotic complications and a possible risk of thrombo-hemorrhagic complications, including the syndrome of disseminated intravascular coagulation. Changes in all links of the hemostasis system in response to the DLHUL test indicate the need to use anticoagulant therapy in patients with an anamnesis of factors provoking a hypercoagulable state as one of the components of preoperative preparation
Ionic liquids at electrified interfaces
Until recently, âroom-temperatureâ (<100â150 °C) liquid-state electrochemistry was mostly electrochemistry of diluted electrolytes(1)â(4) where dissolved salt ions were surrounded by a considerable amount of solvent molecules. Highly concentrated liquid electrolytes were mostly considered in the narrow (albeit important) niche of high-temperature electrochemistry of molten inorganic salts(5-9) and in the even narrower niche of âfirst-generationâ room temperature ionic liquids, RTILs (such as chloro-aluminates and alkylammonium nitrates).(10-14) The situation has changed dramatically in the 2000s after the discovery of new moisture- and temperature-stable RTILs.(15, 16) These days, the âlater generationâ RTILs attracted wide attention within the electrochemical community.(17-31) Indeed, RTILs, as a class of compounds, possess a unique combination of properties (high charge density, electrochemical stability, low/negligible volatility, tunable polarity, etc.) that make them very attractive substances from fundamental and application points of view.(32-38) Most importantly, they can mix with each other in âcocktailsâ of oneâs choice to acquire the desired properties (e.g., wider temperature range of the liquid phase(39, 40)) and can serve as almost âuniversalâ solvents.(37, 41, 42) It is worth noting here one of the advantages of RTILs as compared to their high-temperature molten salt (HTMS)(43) âsister-systemsâ.(44) In RTILs the dissolved molecules are not imbedded in a harsh high temperature environment which could be destructive for many classes of fragile (organic) molecules
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients.
OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs.
DESIGN This was a prospective international 1-week observational study using the âAssess Respiratory Risk in Surgical Patients in Catalonia risk scoreâ (ARISCAT score) for PPC for risk stratification.
PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries.
MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes.
RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure.
CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome
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