Effect of the C/N ratio modification on the corrosion behavior and performance of carbonitride coatings prepared by cathodic arc deposition

This study focuses on investigating carbonitride coatings, specifically CNTi-(Zr, ZrNb, and ZrSi), as promising candidates for enhancing the durability and efficiency of Ti6Al4V materials used in nuclear fusion technology. X-ray diffraction analysis identified distinct phases, including TiN, ZrN, ZrC, and TiC. The corrosion studies showed complete degradation of the TiN, ZrC, and ZrN phases in the TiZrCN coating after tests, while the TiC phase exhibited relative stability. The surface morphologies and elemental mapping analysis demonstrated the loss of homogeneity in element distribution after corrosion process. The addition of Si and Nb elements into TiZrCN significantly influenced the coatings' corrosion behavior, with breakaway corrosion observed in CNTi- (Zr and ZrSi) coatings and localized corrosion in CNTi-(ZrNb) coatings. Notably, the CNTi-(ZrSi) coating formed an oxide phase in the presence of NaCl, whereas the CNTi-(ZrNb) coating exhibited continuous resistance and a low corrosion rate. Irradiation was carried out for the generation of active isotopes, showing that no radioactive isotopes were formed in any of the investigated samples

Mechanical and structural properties of YOYO-1 complexed DNA

YOYO-1 is a fluorescent dye widely used for probing the statistical–mechanical properties of DNA. However, currently contradicting data exist how YOYO-1 binding alters the DNA structure and rigidity. Here, we systematically address this problem using magnetic tweezers. Remarkably, we find that the persistence length of DNA remains constant independent of the amount of bound YOYO-1, which contrasts previous assumptions. While the ionic conditions can considerably alter the stability of YOYO-1 binding, the DNA bending rigidity seems not to be affected. We furthermore determine important structural parameters such as the binding site size, the elongation, as well as the untwisting angle per bound YOYO-1 molecule. We expect that our assay, in which all the parameters are determined within a single experiment, will be beneficial for a large range of other DNA binding drugs

Corrosion and tribological performance of quasi-stoichiometric titanium containing carbo-nitride coatings

Zr, Nb and Si doped TiCN coatings, with (C+N)/(metal + Si) ratios of approximately 1, were deposited on stainless steel and Si wafer substrates using a cathodic arc technique in a mixture of N2 and CH4 gases. The coatings were comparatively analysed for elemental and phase composition, adhesion, anticorrosive properties and tribological performance at ambient and 250 °C. Zr, Nb and Si alloying contents in the coatings were in the range 2.9–9.6 at.%. All the coatings exhibited f.c.c. solid solution structures and had a 〈1 1 1〉 preferred orientation. In the adhesion tests conducted, critical loads ranged from 20 to 30 N, indicative of a good adhesion to substrate materials. The Ti based coatings with Nb or Si alloying elements proved to be resistant to corrosive attack in 3.5% NaCl and of these coatings the TiNbCN was found to have the best corrosion resistance. TiCN exhibited the best tribological performance at 250 °C, while at ambient temperatures it was TiNbCN. Abrasive and oxidative wear was found to be the main wear mechanism for all of the coatings. Of the tested coatings, TiNbCN coatings would be the most suitable candidate for severe service (high temperature, corrosive, etc.) applications

Filling an Emulsion Drop with Motile Bacteria

We have measured the spatial distribution of motile Escherichia coli inside spherical water droplets emulsified in oil. At low cell concentrations, the cell density peaks at the water-oil interface; at increasing concentration, the bulk of each droplet fills up uniformly while the surface peak remains. Simulations and theory show that the bulk density results from a `traffic' of cells leaving the surface layer, increasingly due to cell-cell scattering as the surface coverage rises above $\sim 10\%$. Our findings show similarities with the physics of a rarefied gas in a spherical cavity with attractive walls.Comment: 5 pages, 4 figures, Supporting Information (5 pages, 5 figures

Comparing Skill Acquisition Under Varying Onsets of Differential Reinforcement: A Preliminary Analysis

The purpose of the current study was to evaluate the effect of implementing differential reinforcement at different times relative to the onset of teaching new skills to learners with autism spectrum disorder. Specifically, we first determined the most efficient differential reinforcement arrangement for each participant. Using the most efficient arrangement, we evaluated if differential reinforcement from the immediate onset, early onset, or late onset is the most efficient for learners to acquire a new skill. Three children diagnosed with autism spectrum disorder who have a history of receiving intervention based on the principles of applied behavior analysis participated in this study. The immediate onset of differential reinforcement resulted in the most efficient instruction in 6 of 7 comparisons. The results are discussed in light of previous studies and suggestions for future research are provided

Age of onset and cumulative risk of mental disorders:a cross-national analysis of population surveys from 29 countries

Background: Information on the frequency and timing of mental disorder onsets across the lifespan is of fundamental importance for public health planning. Broad, cross-national estimates of this information from coordinated general population surveys were last updated in 2007. We aimed to provide updated and improved estimates of age-of-onset distributions, lifetime prevalence, and morbid risk. Methods: In this cross-national analysis, we analysed data from respondents aged 18 years or older to the World Mental Health surveys, a coordinated series of cross-sectional, face-to-face community epidemiological surveys administered between 2001 and 2022. In the surveys, the WHO Composite International Diagnostic Interview, a fully structured psychiatric diagnostic interview, was used to assess age of onset, lifetime prevalence, and morbid risk of 13 DSM-IV mental disorders until age 75 years across surveys by sex. We did not assess ethnicity. The surveys were geographically clustered and weighted to adjust for selection probability, and standard errors of incidence rates and cumulative incidence curves were calculated using the jackknife repeated replications simulation method, taking weighting and geographical clustering of data into account. Findings: We included 156 331 respondents from 32 surveys in 29 countries, including 12 low-income and middle-income countries and 17 high-income countries, and including 85 308 (54·5%) female respondents and 71 023 (45·4%) male respondents. The lifetime prevalence of any mental disorder was 28·6% (95% CI 27·9–29·2) for male respondents and 29·8% (29·2–30·3) for female respondents. Morbid risk of any mental disorder by age 75 years was 46·4% (44·9–47·8) for male respondents and 53·1% (51·9–54·3) for female respondents. Conditional probabilities of first onset peaked at approximately age 15 years, with a median age of onset of 19 years (IQR 14–32) for male respondents and 20 years (12–36) for female respondents. The two most prevalent disorders were alcohol use disorder and major depressive disorder for male respondents and major depressive disorder and specific phobia for female respondents. Interpretation: By age 75 years, approximately half the population can expect to develop one or more of the 13 mental disorders considered in this Article. These disorders typically first emerge in childhood, adolescence, or young adulthood. Services should have the capacity to detect and treat common mental disorders promptly and to optimise care that suits people at these crucial parts of the life course. Funding: None.</p

Effect of calcination time on the physicochemical properties and photocatalytic performance of carbon and nitrogen co-doped TiO2 nanoparticles

The application of highly active nano catalysts in advanced oxidation processes (AOPs) improves the production of non-selective hydroxyl radicals and co-oxidants for complete remediation of polluted water. This study focused on the synthesis and characterisation of a highly active visible light C–N-co-doped TiO2 nano catalyst that we prepared via the sol-gel method and pyrolysed at 350 ◦C for 105 min in an inert atmosphere to prevent combustion of carbon moietie