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1.
Wiad Lek ; 77(5): 957-964, 2024.
Article in English | MEDLINE | ID: mdl-39008583

ABSTRACT

OBJECTIVE: Aim: To check the relationships between platelet characteristics and Holter ECG monitoring results in patients with atrial fibrillation (AF) and coronary artery disease (CAD). PATIENTS AND METHODS: Materials and Methods: 300 investigated patients were separated into three groups: I (CAD) - 149 patients with CAD without arrhythmias, II (CAD and AF) - 124 patients with CAD and AF paroxysm, and the control group (CG) - 27 patients without CAD and arrhythmias. RESULTS: Results: In the II group was detected an increase in mean platelet volume (MPV) (9.30%) and platelet-to-leucocyte ratio (PLR) (41.12%) and a decrease in platelet count (PC) (12.20%) in comparison with the I group, P<0.05. Also, in the II group was found an increase in platelet leucine (12.63%), isoleucine (10.73%), and a decrease in serine (5.06%), threonine (23.05%), valine (30.83%), glycine (32.21%) levels in comparison with the I group, P<0.05. PC, MPV, and PLR ratios were correlated with supraventricular extrasystoles per hour (r=-0.352, r=0.308, and r=0.359, consequently), P<0.05. Platelets distribution width (PDW) was correlated with ST-segment changes (r=0.371), P<0.05. Platelet threonine, serine, glycine, alanine, and valine levels were correlated with total supraventricular extrasystoles (r=-0.374, r=-0.358, r=-0.402, r=-0.307, r=-0.312, consequently) and supraventricular extrasystoles per hour (r=-0.374, r=-0.358, r=-0.402, r=-0.307, r=-0.312, consequently), P<0.05. Platelet lysine, taurine, cysteine, and phenylalanine levels were correlated with ST-segment changes (r=-0.319, r=-0.344, r=-0.376, and r=0.317, consequently), P<0.05. CONCLUSION: Conclusions: Platelet features (PC, MPV, PDW, PLR, and amino acid spectrum) are significantly correlated with supraventricular arrhythmias and ST-segment episodes, which shows their role in AF and CAD pathogenesis.


Subject(s)
Atrial Fibrillation , Blood Platelets , Coronary Artery Disease , Electrocardiography, Ambulatory , Humans , Atrial Fibrillation/blood , Atrial Fibrillation/physiopathology , Female , Male , Coronary Artery Disease/blood , Coronary Artery Disease/physiopathology , Middle Aged , Aged , Platelet Count , Mean Platelet Volume
2.
Article in English | MEDLINE | ID: mdl-38772993

ABSTRACT

The sphere-shaped zinc oxide (ZnO) photocatalyst was synthesized by the homogeneous precipitation method, using Zn(CH3COO)2·2H2O as a zinc precursor and NH4OH as a precipitating agent. The morphology and crystal structure of the prepared ZnO sample were studied by XRD, SEM, FT-IR, XPS, zeta potential measurements, and a low-temperature nitrogen adsorption-desorption technique. The optical characteristics of ZnO were determined by UV - Vis diffuse reflectance spectroscopy. ZnO photocatalyst performance of up to 100% within 210 min was observed in the photodegradation of the ofloxacin antibiotic under ultraviolet (UV) irradiation. The effect of antibiotic concentration, heavy metal ions, and water sources on the photocatalytic activity of ZnO demonstrated both the potential of its application under different conditions, and a good adaptability of this photocatalyst. The photodegradation reaction correlated well with the first-order kinetics model, with a rate constant of 0.0173 min-1. The reusability of the photocatalyst was verified after three cycles of use. Admittedly, photogenerated electrons and holes played a key role in removal of the antibiotic. This work showed the suitability of prepared ZnO for antibiotic removal, and its potential use for environmental protection.

3.
Phys Chem Chem Phys ; 26(3): 2440-2448, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38167891

ABSTRACT

Zeolitic imidazolate framework (ZIF) microporous materials have already been employed in many fields of energetic and environmental interest since the last decade. The commercial scale production of some of these materials makes them more accessible for their implementation in industrial processes; however, their massive synthesis may entail modifications to the preparation protocols, which may result in a loss in the optimization of this process and a drop in the material's quality. This fact may have implications for the performance of these materials during their lifetime, especially when they are used in applications such as energy dissipation, in which they are subjected to several operating cycles under high pressures. This study focuses on ZIF-67, a material that has demonstrated in the past its ability to dissipate energy through the water intrusion-extrusion process under high pressure. Two ZIF-67 samples were synthesized using different protocols, and 2 batches of different qualities (labelled as high quality (HQ) and low quality (LQ)) were obtained and analysed by water porosimetry to study their performance in the intrusion-extrusion process. Unexpectedly, minor structural differences, which are typically neglected especially under production conditions, had a dramatic effect on their performance. The results presented in this study reiterate the importance of quality control with respect to reproducibility of experimental results. In a broader perspective, they are critical to the technology transfer from academia to industry.

4.
ACS Appl Mater Interfaces ; 16(1): 1767-1778, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38113456

ABSTRACT

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) are highly promising nanomaterials for various electronic devices such as field-effect transistors, junction diodes, tunneling devices, and, more recently, memristors. 2D MoSe2 stands out for having high electrical conductivity, charge carrier mobility, and melting point. While these features make it particularly appropriate as a switching layer in memristive devices, reliable and scalable production of large-area 2D MoSe2 still represents a challenge. In this study, we manufacture 2D MoSe2 films by atmospheric-pressure chemical vapor deposition and investigate them on the atomic scale. We selected and transferred MoSe2 bilayer to serve as a switching layer between asymmetric Au-Cu electrodes in miniaturized crossbar vertical memristors. The electrochemical metallization devices showed forming-free, bipolar resistive switching at low voltages, with clearly identifiable nonvolatile states. Other than low-power neuromorphic computing, low switching voltages approaching the range of biological action potentials could unlock hybrid biological interfaces.

5.
ACS Appl Electron Mater ; 4(7): 3399-3410, 2022 Jul 26.
Article in English | MEDLINE | ID: mdl-36570334

ABSTRACT

Numerous efforts have been devoted to improve the electronic and optical properties of III-V compound materials via reduction of their nonradiative states, aiming at highly efficient III-V sub-micrometer active devices and circuits. Despite many advances, the poor reproducibility and short-term passivation effect of chemical treatments, such as sulfidation and nitridation, requires the use of protective encapsulation methods, not only to protect the surface, but also to provide electrical isolation for device manufacturing. There is still a controversial debate on which combination of chemical treatment and capping dielectric layer can best reproducibly protect the crystal surface of III-V materials while being compatible with readily available semiconductor-foundry plasma deposition methods. This work reports on a systematic experimental study on the role of sulfide ammonium chemical treatment followed by dielectric coating (either silicon oxide or nitride) in the passivation effect of GaAs/AlGaAs nanopillars. Our results conclusively show that, under ambient conditions, the best surface passivation is achieved using ammonium sulfide followed by encapsulation with a thin layer of silicon nitride by low-frequency plasma-enhanced chemical deposition. Here, the sulfurized GaAs surfaces, high level of hydrogen ions, and low-frequency (380 kHz) excitation plasma that enable intense bombardment of hydrogen, all seem to provide a combined active role in the passivation mechanism of the pillars by reducing the surface states. As a result, we observe up to a 29-fold increase of the photoluminescence (PL) integrated intensity for the best samples as compared to untreated nanopillars. X-ray photoelectron spectroscopy analysis confirms the best treatments show remarkable removal of gallium and arsenic native oxides. Time-resolved micro-PL measurements display nanosecond lifetimes resulting in a record-low surface recombination velocity of ∼1.1 × 104 cm s-1 for dry-etched GaAs nanopillars. We achieve robust, stable, and long-term passivated nanopillar surfaces, which creates expectations for remarkable high internal quantum efficiency (IQE > 0.5) in nanoscale light-emitting diodes. The enhanced performance paves the way to many other nanostructures and devices such as miniature resonators, lasers, photodetectors, and solar cells, opening remarkable prospects for GaAs active nanophotonic devices.

6.
Wiad Lek ; 75(12): 3074-3079, 2022.
Article in English | MEDLINE | ID: mdl-36723330

ABSTRACT

OBJECTIVE: The aim: To study the possibilities of alpha-lipoic acid (ALA) to control the parameters of carbohydrate metabolism. PATIENTS AND METHODS: Materials and methods: We examined 80 people with type 2 DM and coronary heart disease who suffered non-Q-myocardial infarction (non-Q-MI). All patients at the time of inclusion in the study received oral hypoglycemic agents, ACE inhibitor, ß-blocker, statin and antiplatelet agent. 600 mg of ALA per day for 4 months was added to this treatment. After checking the patients for compliance with the criteria, they were divided into the main and experimental groups. The dosage of alpha-lipoic acid was determined for each of the groups. The results of the treatment were analyzed by determining the mean and standard deviations. RESULTS: Results: At the end of the observation period, a significant decrease in the level of fasting glucose (FG) by 11.6% was found, which corresponded to the average size of the clinical effect. The values of glycosylated hemoglobin (HbA1c) and the insulin resistance index HOMA (HOMA-IR) showed only a tendency to decrease on the background of treatment. The effect of ALA on postprandial glycemia (PPG) and insulin levels was not detected in this study. CONCLUSION: Conclusions: An additional 4-month dose of ALA in addition to baseline therapy showed a moderate effect on the decrease in FG concentration in the absence of significant dynamics in other parameters of glycemic control in the examined patients.


Subject(s)
Diabetes Mellitus, Type 2 , Thioctic Acid , Humans , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Thioctic Acid/therapeutic use , Blood Glucose/metabolism , Glycated Hemoglobin , Insulin/therapeutic use , Syndrome , Hypoglycemic Agents/therapeutic use
7.
Front Neurosci ; 15: 663174, 2021.
Article in English | MEDLINE | ID: mdl-34211364

ABSTRACT

Flexible polymer neural probes are an attractive emerging approach for invasive brain recordings, given that they can minimize the risks of brain damage or glial scaring. However, densely packed electrode sites, which can facilitate neuronal data analysis, are not widely available in flexible probes. Here, we present a new flexible polyimide neural probe, based on standard and low-cost lithography processes, which has 32 closely spaced 10 µm diameter gold electrode sites at two different depths from the probe surface arranged in a matrix, with inter-site distances of only 5 µm. The double-layer design and fabrication approach implemented also provides additional stiffening just sufficient to prevent probe buckling during brain insertion. This approach avoids typical laborious augmentation strategies used to increase flexible probes' mechanical rigidity while allowing a small brain insertion footprint. Chemical composition analysis and metrology of structural, mechanical, and electrical properties demonstrated the viability of this fabrication approach. Finally, in vivo functional assessment tests in the mouse cortex were performed as well as histological assessment of the insertion footprint, validating the biological applicability of this flexible neural probe for acquiring high quality neuronal recordings with high signal to noise ratio (SNR) and reduced acute trauma.

8.
Acta Sci Pol Technol Aliment ; 20(2): 197-211, 2021.
Article in English | MEDLINE | ID: mdl-33884857

ABSTRACT

BACKGROUND: The search for new plant raw material as a potential source of antioxidants is still ongoing. This study aimed to evaluate the antioxidant and antimicrobial capacity of the plant raw material of Crambe spp. during vegetation. METHODS: The free radical scavenging activity and molybdenum reducing power of the extracts were used to determine antioxidant activity. The quantification of polyphenol compounds was conducted with Folin-Ciocalteu reagent. Flavonoids and phenolic acids were also determined. The disc diffusion method was used to determine antimicrobial activity. RESULTS: It was determined that the free radical scavenging activity, assessed using the DPPH-method, was 4.38-8.20 mg TE/g DW, the molybdenum reducing power of the extracts was 40.07-129.12 mg TE/g DW, total polyphenol content was 20.24-70.88 mg GAE/g DW, total flavonoid content was 5.73-29.92 mg QE/g DW, and phenolic acid content was 3.00-10.63 mg CAE/g DW. Antimicrobial activity depended on the stage of growth and the part of the plant used. CONCLUSIONS: Crambe spp. possess the antioxidant and antimicrobial potential to mean that they could be used in pharmaceutical studies and the food industry.


Subject(s)
Anti-Infective Agents/pharmacology , Antioxidants/pharmacology , Brassicaceae/chemistry , Flavonoids/pharmacology , Phenols/pharmacology , Plant Extracts/pharmacology , Anti-Infective Agents/analysis , Antioxidants/analysis , Brassicaceae/classification , Flavonoids/analysis , Hydroxybenzoates/analysis , Hydroxybenzoates/pharmacology , Microbial Sensitivity Tests , Phenols/analysis , Plant Components, Aerial , Plant Extracts/chemistry , Polyphenols/analysis , Polyphenols/pharmacology , Species Specificity
9.
Nat Commun ; 11(1): 3634, 2020 Jul 20.
Article in English | MEDLINE | ID: mdl-32686684

ABSTRACT

The electrical and optoelectronic properties of materials are determined by the chemical potentials of their constituents. The relative density of point defects is thus controlled, allowing to craft microstructure, trap densities and doping levels. Here, we show that the chemical potentials of chalcogenide materials near the edge of their existence region are not only determined during growth but also at room temperature by post-processing. In particular, we study the generation of anion vacancies, which are critical defects in chalcogenide semiconductors and topological insulators. The example of CuInSe2 photovoltaic semiconductor reveals that single phase material crosses the phase boundary and forms surface secondary phases upon oxidation, thereby creating anion vacancies. The arising metastable point defect population explains a common root cause of performance losses. This study shows how selective defect annihilation is attained with tailored chemical treatments that mitigate anion vacancy formation and improve the performance of CuInSe2 solar cells.

10.
J Med Life ; 13(1): 32-36, 2020.
Article in English | MEDLINE | ID: mdl-32341698

ABSTRACT

Patients with combined coronary heart disease and diabetes mellitus make up a growing segment of the population and require a comprehensive treatment approach. Patients with concurrent diabetes mellitus and coronary heart disease have a worse projection. Under these conditions, the incidence of recurrent myocardial infarction, early disability due to complications, and the risk of coronary death are increased. Therefore, the priority task is to find ways to optimize drug treatment of this category of patients, taking into account the impact of drugs on the pathogenetic links of coronary heart disease progression and the development of cardiovascular complications. One hundred twelve people were examined in the research. The patients had type 2 diabetes with a history of non-Q-myocardial infarction receiving oral antidiabetic therapy and basic therapy, including an ACE inhibitor, a ß-blocker, a statin, and an antiplatelet agent. Analysis of the investigated parameters in the leading group after receiving alpha-lipoic acid for 4 months showed a significant decrease in the concentration of C-Reactive Protein, IL-6 and TNF-α. According to the results of our research, taking alpha-lipoic acid for 4 months in patients with type 2 diabetes who underwent non-Q-myocardial infarction reduced the activity of systemic inflammation and did not significantly affect the content of anti-inflammatory IL-10 in patients. In light of the above, it is of interest to administer alpha-lipoic acid to these patients, considering the positive effects of the agent such as antioxidant properties, vasorelaxation, positive metabolic profile, as well as an anti-inflammatory potential.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Inflammation/drug therapy , Myocardial Infarction/complications , Thioctic Acid/therapeutic use , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , C-Reactive Protein/metabolism , Coronary Artery Disease/complications , Cytokines/metabolism , Diabetes Mellitus, Type 2/complications , Female , Humans , Inflammation/complications , Male , Middle Aged
11.
Nanoscale ; 12(9): 5669-5677, 2020 Mar 07.
Article in English | MEDLINE | ID: mdl-32101234

ABSTRACT

Engineering multicomponent electroactive materials is an effective strategy to improve electrochemical performance by adjusting the atomic and electronic structure. In this work, we directly synthesize oriented bimetallic CoNi-MOF nanosheets on CFP (carbon fiber paper). The CoNi-MOF/CFP shows high specific capacitance, outstanding rate capability and long-term cycling stability compared to a monometallic Ni-MOF or Co-MOF. By adjusting the Co/Ni molar ratio, CoNi23/CFP (Co : Ni = 2 : 3) displays the highest specific capacitance (2033 F g-1 at 1 A g-1). The introduction of Co into the Ni-MOF matrix shortens Co/Ni-centered bond distances, resulting in improved bond strength, facilitating the charge transfer and increasing the electrical conductivity of the CoNi-MOF, which were proved by X-ray absorption fine structure (XAFS) spectroscopy, high angle annular dark field (HAADF) imaging, and electrochemical impedance spectroscopy (EIS). Our study demonstrates the origin of performance improvements and, therefore, may provide a feasible scheme to unlock high-performance MOF electrode materials.

12.
Wiad Lek ; 72(9 cz 2): 1791-1794, 2019.
Article in English | MEDLINE | ID: mdl-31622268

ABSTRACT

OBJECTIVE: Introduction: At present biocomposite materials are used in the surgical treatment of frontal bone fracture. They improve osteogenesis, reduce the number of complications. Immunologic aspects of application of these materials are studied insufficiently, therefore this report presents the results of immunoassay of patients with frontal bone fracture in the proximate posttraumatic period before implanting preparation "Syntekost". The aim: To define the role of immune mechanisms in the realization of the biocomposite material's positive influence on the development of effective posstraumatic rehabilitation schemes. PATIENTS AND METHODS: Materials and methods: 16 patients with frontal bone fracture (FBF) were examined on admission to the Otolaryngology Clinics of Vinnitsa Region Hospital. Additionally, 10 patients of the similar age were examined as a control group. The content of cells with markers of surface antigens-CD3,14,16,20,25, concentration of immunoglobulins of classes M,G,A,E, С4 complement component and lactoferrin was determined in blood. Immunoenzyme methods were applied. Nonparametric Wilcoxon - Mann - Whitney test, computer programme WIN Pepi were used for statistical measurements. RESULTS: Results: A decrease in the level of IgM in comparison with practically healthy donors and an increase in the concentration of lactoferrin were identified as humoral immunity factors of patients with frontal basilar trauma. The most significant deviation in the peripheral blood cellular makeup in CD-markers was an increase in cells with markers CD14 and CD16. CONCLUSION: Conclusions: The level of cells and prodefensin-lactoferrin that maintain inborn immunity increases and the concentration of coarse defensive protein decreases in the initial period after frontal bone fracture, which must be taken into consideration during post-surgical treatment.


Subject(s)
Frontal Bone/injuries , Immunity, Cellular , Immunity, Humoral , Antigens, CD/analysis , Humans , Immunoglobulins/blood , Lactoferrin/blood
13.
Wiad Lek ; 72(10): 1904-1908, 2019 Oct 31.
Article in English | MEDLINE | ID: mdl-31982011

ABSTRACT

Introduction: Scleroma is a rare chronic granulomatous disease of the upper respiratory tract caused by Klebsiella pneumoniae subsp. rhinoscleromatis. To date its pathogenesis is as yet little understood. At the same time, scleroma is associated with a number of immune system disturbances. The aim: To study local immunity status of oropharynx in patients with scleroma, and to compare its parameters in various clinical forms of the disease. Material and methods: 20 apparently healthy subjects and 92 patients with scleroma (33 males, 59 females) underwent clinical immunologic evaluation. There were 31 patients with dominating infiltrative form of scleroma, 30 ­ with dominating atrophic form, 31 ­ with dominating scarring form. Concentration of secretory and monomeric immunoglobulin A, immunoglobulin G, α-interferon, interleukin 1ß in oropharyngeal secretion was determined by enzyme immunoassay. Resluts: Patients with scleroma were found to have altered local immunity of oropharyngeal secretion. There was a strong tendency for decreased concentration of secretory immunoglobulin A - 1.3-2.0 times, and decreased immunoglobulin G level ­ 1.5-2.3 times (р < 0.05) as compared to the values in healthy subjects. Specific features of local immunity in oropharyngeal secretion in various forms of scleromatous inflammatory process in upper respiratory tract were found: the most significant decrease of α-interferon concentration in atrophic and scarring forms of the disease, and the largest increase of anti-inflammatory interleukin 1ß and immune complex concentration in infiltrative form of scleroma. Conslusions: The study revealed deficiency of local immunity factors in oropharynx, being indicative of immunopathogenetic role of diagnosed disturbances in development and persistence of chronic inflammation in scleroma, and emphasizing the necessity of immunocorrection in complex therapy of the disease.


Subject(s)
Larynx , Rhinoscleroma , Female , Humans , Klebsiella pneumoniae , Male , Nose , Oropharynx
14.
Wiad Lek ; 71(7): 1281-1288, 2018.
Article in English | MEDLINE | ID: mdl-30448797

ABSTRACT

OBJECTIVE: Introduction: The problem of bone tissue regeneration and the development of the methods of directional influence on bone healing processes are one of the most urgent problems of modern medicine. The question of bone tissue posttraumatic regeneration is particularly important with regard to military conflicts, ecological and technological disasters, and has social and economic relevance, connected with the necessity of long-term treatment and medical rehabilitation. The aim: The objective of the work is the experimental evaluation of bone tissue reparative regeneration during the implantation of biocomposite "Syntekost" (patent for invention №98573 dated 25.05.2012 Ukraine), and аlso dynamics determination of bone tissue reparative regeneration after its application during a year. PATIENTS AND METHODS: Materials and methods: The experiment was carried out on 24 rabbits. All the rabbits were divided into three groups. Penetrating bone damages on the edge of the proximal tibial metaphysis and diaphysis with the diameter of 2,2 mm were formed in the rabbits of the first group using intravenous anesthetic and the dynamics of the reparative regeneration of bone tissue of the iliac crest was studied in 6, 9 and 12 months, without using composite "Syntekost" (control group - 8 rabbits). Penetrating bone damageson the edge of the proximal tibial metaphysis and diaphysis with the diameter of 2,2 mm were formed in the rabbits of the second group and biocomposite "Syntekost" was implantated into them (8 rabbits). Penetrating bone damages on the edge of the proximal tibial metaphysis and diaphysis with the diameter of 2,2 mm were formed in the rabbits of the third group and biocomposite "Syntekost" was implantated into them together with blood plasma and ossein-hydroxyapatite (8 rabbits). RESULTS: Results: In all stages the research showed the significantly higher percentage of splenial bone tissue both in the rabbits that had biocomposite "Syntekost" implanted withoutblood plasma and ossein-hydroxyapatite and in the rabbits that had biocomposite "Syntekost" implanted with blood plasma and ossein-hydroxyapatite in comparison with the one of the rabbits that didn't have biocomposite "Syntekost" implanted after having been injured (р < 0,05). In all stages of the research the rabbits that had biocomposite "Biokost" implanted together with blood plasma and ossein-hydroxyapatite had the significantly higher percentage of neogenic splenial bone tissue and the significantly lower percentage of biocomposite "Syntekost" comparing to the ones of the rabbits that had biocomposite "Syntekost" implanted without blood plasma and ossein-hydroxyapatite (р < 0,05). CONCLUSION: Conclusions: The application of blood plasma and ossein-hydroxyapatite accelerates bone tissue regeneration and the process of biodegradation of biocomposite "Syntekost" throughout the experiment. In all stages of the experiment no toxic influence of biocomposite "Syntekost" on the surrounding bone tissue was found.


Subject(s)
Biocompatible Materials/therapeutic use , Bone Regeneration , Durapatite/therapeutic use , Ilium/injuries , Animals , Plasma , Rabbits , Wound Healing
15.
Langmuir ; 34(48): 14528-14536, 2018 12 04.
Article in English | MEDLINE | ID: mdl-30412414

ABSTRACT

Thin films of ionic liquid 1-ethyl-3-methylimidazolium bis(fluoromethylsulfonyl)imide ([EMIm][FSI]) vapor-deposited on highly oriented pyrographite (HOPG) were studied by X-ray photoelectron spectroscopy and atomic force microscopy. The results revealed a reversible morphological transition from a "drop-on-layer" structure to a "flat-layer" structure at positive, and not at negative, polarization. The effect is rationalized in terms of electric-field-induced reduction of the liquid-solid transition temperature in the ionic liquid film, when its thickness is comparable to the charge screening length. The observed bias asymmetry of [EMIm][FSI] electrowetting on HOPG is tentatively explained by the bilayer structure at the interface driven by the affinity of the imidazolium ring to the HOPG surface.

16.
J Am Chem Soc ; 140(31): 9921-9933, 2018 08 08.
Article in English | MEDLINE | ID: mdl-30008214

ABSTRACT

With a remarkably higher theoretical energy density compared to lithium-ion batteries (LIBs) and abundance of elemental sulfur, lithium sulfur (Li-S) batteries have emerged as one of the most promising alternatives among all the post LIB technologies. In particular, the coupling of solid polymer electrolytes (SPEs) with the cell chemistry of Li-S batteries enables a safe and high-capacity electrochemical energy storage system, due to the better processability and less flammability of SPEs compared to liquid electrolytes. However, the practical deployment of all solid-state Li-S batteries (ASSLSBs) containing SPEs is largely hindered by the low accessibility of active materials and side reactions of soluble polysulfide species, resulting in a poor specific capacity and cyclability. In the present work, an ultrahigh performance of ASSLSBs is obtained via an anomalous synergistic effect between (fluorosulfonyl)(trifluoromethanesulfonyl)imide anions inherited from the design of lithium salts in SPEs and the polysulfide species formed during the cycling. The corresponding Li-S cells deliver high specific/areal capacity (1394 mAh gsulfur-1, 1.2 mAh cm-2), good Coulombic efficiency, and superior rate capability (∼800 mAh gsulfur-1 after 60 cycles). These results imply the importance of the molecular structure of lithium salts in ASSLSBs and pave a way for future development of safe and cost-effective Li-S batteries.

17.
Wiad Lek ; 70(5): 998-1004, 2017.
Article in English | MEDLINE | ID: mdl-29203757

ABSTRACT

Non-compacted left ventricle in adults is a rare occurrence, though it is diagnosed even more rarely. As a rule in patients with non-compacted left ventricle (LVNC) other pathologic condition is diagnosed, notably hypertrophic or dilated cardiomyopathy. The majority of LVNC cases are diagnosed in early infancy but currently there are asymptomatic cases detected by means of echocardiographic examination. Real prevalence of LVNC is unknown. According to many authors LVNC occurs in 9.2-9.5% of children with diagnosed cardiomyopathies. The majority of such children do not survive till adulthood because of progressive severe heart failure, fatal arrhythmias and thromboembolisms. This value ranges from 0.014 to 0.05% in adult population. The article presents a clinical case illustrating the stages in establishing the diagnosis of non-compacted left ventricle in a young patient with myocardial infarction and congestive heart failure. Common characteristics of non-compacted left ventricle and connective tissue dysplasia syndrome in the patient suggested etiopathogenetic relationship between these two pathologic states. The basic common characteristic feature of both non-compacted left ventricle and connective tissue dysplasia syndrome proved to be multiple abnormal chords of the left ventricle. The patient was supposed to have some coronary circulation abnormality inherited together with non-compacted left ventricle and connective tissue dysplasia syndrome. Adverse prognosis and high mortality in non-compacted left ventricle require its early recognition and differentiated approach to treatment depending on the severity of the disease and using all modern methods of treatment both conservative and surgical.


Subject(s)
Isolated Noncompaction of the Ventricular Myocardium/diagnostic imaging , Isolated Noncompaction of the Ventricular Myocardium/physiopathology , Adult , Cardiomyopathy, Dilated/pathology , Child , Echocardiography , Heart Ventricles/pathology , Humans , Medical History Taking
18.
Angew Chem Int Ed Engl ; 56(48): 15368-15372, 2017 11 27.
Article in English | MEDLINE | ID: mdl-28994228

ABSTRACT

Of the various beyond-lithium-ion battery technologies, lithium-sulfur (Li-S) batteries have an appealing theoretical energy density and are being intensely investigated as next-generation rechargeable lithium-metal batteries. However, the stability of the lithium-metal (Li°) anode is among the most urgent challenges that need to be addressed to ensure the long-term stability of Li-S batteries. Herein, we report lithium azide (LiN3 ) as a novel electrolyte additive for all-solid-state Li-S batteries (ASSLSBs). It results in the formation of a thin, compact and highly conductive passivation layer on the Li° anode, thereby avoiding dendrite formation, and polysulfide shuttling. It greatly enhances the cycling performance, Coulombic and energy efficiencies of ASSLSBs, outperforming the state-of-the-art additive lithium nitrate (LiNO3 ).

19.
Angew Chem Int Ed Engl ; 53(23): 5998-6001, 2014 Jun 02.
Article in English | MEDLINE | ID: mdl-24840397

ABSTRACT

A symbiosis of advanced scanning probe and electron microscopy and a well-defined model system may provide a detailed picture of interfaces on nanostructured catalytic systems. This was demonstrated for Pt nanoparticles supported on iron oxide thin films which undergo encapsulation by supporting oxide as a result of strong metal-support interactions.

20.
Respir Med ; 107(5): 691-701, 2013 May.
Article in English | MEDLINE | ID: mdl-23478193

ABSTRACT

BACKGROUND: Preventing and managing exacerbations is one major component in COPD treatment. We investigated whether EPs 7630, a herbal drug preparation from the roots of Pelargonium sidoides, could prolong time to acute exacerbation in patients with COPD stage II/III. METHODS: In this randomised, double-blind, placebo-controlled clinical trial, patients were randomly allocated to oral 24-week add-on therapy with 3 × 30 drops/day EPs 7630 (n = 99) or placebo (n = 101) to a standardised baseline-treatment. Primary endpoint was time to first exacerbation of COPD. Secondary endpoints were number of exacerbations, consumption of antibiotics, quality of life, patient satisfaction, inability to work, and tolerability. RESULTS: Median time to exacerbation was significantly prolonged with EPs 7630 compared to placebo (57 versus 43 days, Kaplan-Maier-estimate; p = 0.005, one-sided centre-stratified log-rank test). The superiority of EPs 7630 was also confirmed in secondary endpoints, e.g., fewer exacerbations, less patients with antibiotic use, improved quality of life, higher patient satisfaction, and less days of inability to work. The incidence of minor gastrointestinal adverse events was higher in the EPs 7630 group. CONCLUSIONS: The results demonstrate a statistically significant and clinically relevant superiority of add-on therapy with EPs 7630 over placebo and a good long-term tolerability in the treatment of moderate to severe COPD. EPs 7630 prolonged time to exacerbations and reduced exacerbation frequency and antibiotic use. Trial Registration No.: ISRCTN01681733.


Subject(s)
Anti-Infective Agents/therapeutic use , Phytotherapy/methods , Plant Extracts/therapeutic use , Pulmonary Disease, Chronic Obstructive/drug therapy , Respiratory System Agents/therapeutic use , Acute Disease , Adult , Aged , Anti-Infective Agents/adverse effects , Comorbidity , Double-Blind Method , Female , Forced Expiratory Volume/drug effects , Humans , Male , Middle Aged , Patient Satisfaction , Plant Extracts/adverse effects , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory System Agents/adverse effects , Treatment Outcome , Vital Capacity/drug effects
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