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La1−xAgxFeO3 (x = 0.05–0.25) perovskites deposited on a honeycomb-shaped monolithic metallic support were used as catalysts for the total oxidation of hydrocarbons. Monolithic catalysts were prepared by washcoating honeycomb substrates with lanthanum-stabilized γ-Al2O3, on which La1−xAgxFeO3 was deposited. Catalysts with La1−xAgxFeO3 perovskites show higher activity for methane oxidation at x ≥ 0.05 and hexane oxidation at x ≥ 0.1 than LaFeO3 catalyst. The perovskite catalysts were characterized by XRD, XPS, SEM, TEM, TPR-H2, O2-TPD and BET specific surface area measurement. Ag forms solid solutions with the La1−xAgxFeO3 perovskite lattice for x = 0.05–0.1. In La1−xAgxFeO3 perovskites (x ≥ 0.1), Ag0 particles with average crystallite sizes from 31 to 41 nm were also identified. When Ag is introduced into the LaFeO3 perovskite, both the changes occurring after some Ag is incorporated into its structure and the presence of large crystallites of metallic silver contribute to the catalysts' activity increase. [ABSTRACT FROM AUTHOR]

Ni-P\nano-ZrO2 composite coatings were obtained on the AISI 304 steel substrate by the electroless method from a bath containing dodecyltrimethylammonium bromide (DTAB). This cationic surfactant prevents ZrO2 agglomeration in the bath and affects the ZrO2 content in the coating, hence it alters functional properties of the coatings. It has been found in this study that corrosion resistance of the composite coatings depends on the surfactant concentration in the bath.The estimation of corrosion resistance was carried out by electrochemical impedance spectroscopy. The degree of the sample surface coverage with corrosion products was determined by the machine vision method.The coating obtained from the 0.88 g/dm3 DTAB solution showed the best protective properties. The machine vision method was shown to be an effective complementary tool to evaluate protective properties of the coatings. [ABSTRACT FROM AUTHOR]

Ni-P matrix, ternary Ni-W-P and Ni-P-ZrO2 coatings, and quaternary Ni-W-P-ZrO2 coatings were deposited using electroless method from a glycine bath. Their corrosion resistance was evaluated by electrochemical impedance spectroscopy (EIS) for various immersion times in a 3.5% NaCl solution. From among the investigated coatings, the ternary Ni-W-P coatings show the highest resistance to corrosion in the first hour of exposure to the 3.5% NaCl medium. An addition of ZrO2 adversely affects the performance of both the Ni-P coatings and the Ni-W-P coatings. For all the coatings, including the ones containing tungsten, a marked decrease in pore resistance (Rpor) over time is observed. This means that their corrosion resistance and capacity to protect the substrate decline. On the other hand, after 24 h immersion in the 3.5% NaCl solution the Ni-W-P coating shows the highest low-frequency impedance modulus (| Z|f = 0.01 Hz). As regards corrosion resistance, the Ni-P coatings and the Ni-W-P coatings perform best. [ABSTRACT FROM AUTHOR]

Abstract: One-, three- and five-layer SiO2–Al2O3 coatings were deposited on a FeCrAl alloy basis by the sol–gel method. Sols in which the molar ratio of tetraethoxysilan to aluminium tri-sec-butoxide was 1:1 and 1:3 were used. As the samples were being soaked at T =1200°C for t =700h the mass of the samples increased. Thermal shock (T =1200°C, 10,000 cycles) causes greater degradation of the surface than soaking at a constant temperature. The XPS and EDS results show that the composition of the top layer of the coatings changes during high temperature oxidation and thermal shock. The outward movement of aluminium cations results in surface enrichment with aluminium, particularly for the single-layer coatings. The measured energies of bonds Si 2p and Al 2p in the multilayer coatings indicate that a structure of aluminosilicates with a composition between that of mullite and that of sillimanite forms during sintering. [Copyright &y& Elsevier]

The motion of ions in an electric field for solutions containing Cu2+ ions in the presence of 2-phosphonobutane- 1,2,4-tricarboxylic acid (PBTC), N-trismethylenephosphonic acid (NTMP) and N-(phosphonomethyl) imino-diacetic acid (PMIDA) was investigated using a capillary electrophoresis analyzer. Satisfactory agreement between the cation isotachophoretic determination results and the results calculated from the protonation constants of the relevant ligand species and the stability constants of copper complexes was obtained. The research results can be useful for the electrokinetic method of removing copper from soil. [ABSTRACT FROM AUTHOR]

This paper presents results of a research on the corrosion resistance of composite Ni/Al2O3 coatings electrochemically deposited from Watts baths containing different amounts (0, 20, 100 g dm-3) of Al2O3 particles. Potentiodynamic tests and electrochemical impedance spectroscopy (EIS) measurements were carried out in a 3% solution of NaCl. The coatings with about 6 wt-% of corundum, deposited from a bath with 100 g dm-3 of a powder, showed the best protective properties. The rate of corrosion of such coatings after 7 days of exposure in the NaCl solution was over two times slower than that of coatings containing 2 wt-% of Al2O3 and six times slower than that of a standard nickel coating. Two equivalent circuits: one consisting of two RC circuits and the other one made up of three RC circuits were used for the analysis of the impedance spectra. Regardless of the presence and amount of the Al2O3 particles in the nickel coating, during first day of exposure in the NaCl solution a layer of nickel oxides and hydroxides forms on the surface of the coatings increasing their corrosion resistance. In the case of coatings with 6 wt-% of Al2O3, the passive layer is least vulnerable to the aggressive action of Cl- ions. [ABSTRACT FROM AUTHOR]

The effectiveness of under-air n-hexane oxidation over monolithic catalysts made of heat-resistant foil, containing Pt, Pd or Pt-Pd, was compared. Pt and Pd precursors, either containing chlorine or devoid of chlorine, were used to prepare the catalysts. The chlorine- containing Pt (H2PtCl6) and Pd (PdCl2) precursors were found to lower the activity of the catalysts in hexane oxidation. Studies of the effect of 0.15% Pt/Al2O3 catalyst (using H2PtCl6 as the precursor) calcination conditions on catalyst activity showed the catalyst calcined in static air at 500°C to be the most active. Airflow calcination of the catalyst does not change its catalytic properties. In comparison with the 0.5% Pd/Al2O3 catalyst obtained from Pd(NO3)2, the use of a bimetallic 0.5% Pd/0.1% Pt/Al2O3 catalyst, in which the precursors were Pd(NO3)2 and Pt(NO3)4, resulted in the lowering of 10% and 50% n-hexane temperature by 15°C and 10°C.

The influence of organic additives on the process of surface electropolishing of AISI 304 type steel was determined. Additives were selected in initial potentiodynamic tests pursuant to the plateau analysis on the current/potential curves. The assessment of the operational effectiveness of additives consisted in determining the relationship between surface gloss after electropolishing and the mass loss of the sample and in determining surface roughness. The applied electropolishing bath consisted of a mixture of concentrated acids: H3PO4 and H2SO4, and the following organic additives were used: triethylamine, ethanolamine, diethanolamine, triethanolamine, diethylene glycol monobutyl ether and glycerol. The best electropolishing result, i.e. low roughness and high gloss of stainless steel surface with a relatively low mass loss of the sample at the same time were obtained for baths containing triethanolamine.

To date, the effectiveness of direct-acting antivirals (DAAs) discontinued before 4 weeks has not been analysed in routine clinical practice. The study aimed to determine whether such a short therapy will enable achieving a sustained virological response under real-world experience. The study population of 97 patients who discontinued DAA therapy and had data enabling analysis of patient and disease characteristics, and assessment of treatment effectiveness was selected from 16,815 patients registered in the EpiTer-2 database. The most common reason for discontinuation was hepatic decompensation (20.6%) or the patient's personal decision (18.6%). Patients who discontinued treatment were significantly older, more frequently therapy-experienced, more likely to have cirrhosis, a history of decompensation and a Child-Pugh B or C classification than those who completed treatment. SVR was achieved by 93.5% of patients who discontinued treatment after 4 weeks, 60.9% if discontinued at 3 or 4 week and 33.3% at Week 1 or 2. Patients receiving pangenotypic but not genotype-specific treatment who discontinued after 4 weeks were as likely to achieve SVR as those who completed therapy. Patients who responded to treatment that lasted no longer than 2 weeks had a low baseline viral load (<400,000 IU/mL). Despite discontinuation of therapy after Week 4, the chances of SVR are high. Very early discontinuation does not preclude therapeutic success, especially in patients with low baseline viral load., (© 2024 John Wiley & Sons Ltd.)

Background: Eliminating hepatitis C virus (HCV) infections is a goal set by the World Health Organization. This has become possible with the introduction of highly effective and safe direct-acting antivirals (DAA) but limitations remain due to undiagnosed HCV infections and loss of patients from the cascade of care at various stages, including those lost to follow-up (LTFU) before the assessment of the effectiveness of the therapy. The aim of our study was to determine the extent of this loss and to establish the characteristics of patients experiencing it., Methods: Patients with chronic HCV infection from the Polish retrospective multicenter EpiTer-2 database who were treated with DAA therapies between 2015 and 2023 were included in the study., Results: In the study population of 18,968 patients, 106 had died by the end of the 12-week post-treatment follow-up period, and 509 patients did not report for evaluation of therapy effectiveness while alive and were considered LTFU. Among patients with available assessment of sustained virological response (SVR), the effectiveness of therapy was 97.5%. A significantly higher percentage of men (p<0.0001) and a lower median age (p=0.0001) were documented in LTFU compared to the group with available SVR assessment. In LTFU patients, comorbidities such as alcohol (p<0.0001) and drug addiction (p=0.0005), depression (p=0.0449) or other mental disorders (p<0.0001), and co-infection with human immunodeficiency virus (HIV) (p<0.0001) were significantly more common as compared to those with SVR assessment. They were also significantly more often infected with genotype (GT) 3, less likely to be treatment-experienced and more likely to discontinue DAA therapy., Conclusions: In a real-world population of nearly 19,000 HCV-infected patients, we documented a 2.7% loss to follow-up rate. Independent predictors of this phenomenon were male gender, GT3 infection, HIV co-infection, alcohol addiction, mental illnesses, lack of prior antiviral treatment and discontinuation of DAA therapy., (© 2024. The Author(s).)

Long COVID (LC) is characterized by persistent symptoms following SARS-CoV-2 infection, with various mechanisms offered to explain its pathogenesis. This study explored whether adaptive humoral anti-SARS-CoV-2 responses differ in LC. Unvaccinated COVID-19 convalescents (n = 200) were enrolled, with 21.5% (n = 43) presenting LC three months post-infection. LC diagnosis was based on persistent symptom(s) and alterations in biochemical/clinical markers; three phenotypes were distinguished: cardiological, pulmonary, and psychiatric LC. All three phenotypes were characterized by significantly decreased seroprevalence of IgG antibodies against nucleocapsid (anti-NP). LC was associated with decreased odds of testing positive for anti-NP (OR = 0.35, 95%CI: 0.16-0.78, p = 0.001). Seropositive LC patients had lower anti-S1 and anti-S2 levels than individuals without LC, and those with pulmonary and psychological phenotypes also revealed decreased anti-RBD concentrations. The results indicate that LC can be characterized by diminished humoral response to SARS-CoV-2. The potential implication of this phenomenon in post-acute viral sequelae is discussed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Actinomycosis is a very rare, infectious disease, which is especially difficult to diagnose due to non-specific symptoms and the ability to emulate neoplasms or inflammatory changes. Due to those facts, it is often misdiagnosed or diagnosed too late to be successfully treated. This article presents the case of 31-year-old Caucasian female with recurrent upper respiratory tract infections and tonsillitis as the potential risk factors of actinomycosis. Upon examination of material collected through the course of tonsillectomy, the patient was diagnosed with actinomycosis of the left palatine tonsil. Despite the introduction of antibiotic therapy, initial progression was noted with the appearance of numerous, hypodense changes in the liver and the spleen, which regressed during further antibiotic treatment. According to our team's knowledge, this is the first described case of a patient with actinomycosis occurring simultaneously in the cervico-facial and abdominal area. The unusual localization and potential dissemination of actinomycosis should be considered in clinical practice.