Engineering of Adhesion at Metal-Poly(lactic acid) Interfaces by Poly(dopamine):The Effect of the Annealing Temperature

Control over adhesion at interfaces from strong bonding to release between thermoplastic polymers (TPs) and metal oxides is highly significant for polymer composites. In this work, we showcase a simple and inexpensive method to tune adhesion between a TP of growing interest, poly(lactic acid) (PLA), and two commercial metal alloys, based on titanium and stainless steel. This is realized by coating titanium and stainless steel wires with polydopamine (PDA), thermally treating them under vacuum at temperatures ranging from 25 to 250 °C, and then comolding them with PLA to form pullout specimens for adhesion tests. Pullout results indicate that PDA coatings treated at low temperatures up to a given threshold significantly improve adhesion between PLA and the metals. Conversely, at higher PDA annealing temperatures beyond the threshold, interfacial bonding gradually declines. The excellent control over interfacial adhesion is attributed to the thermally induced transformation of PDA. In this work, we show using thermogravimetric analysis, X-ray photoelectron spectroscopy, Fourier transform infrared, and 13C solid-state NMR that the extent of the thermal transformation is dependent on the annealing temperature. By selecting the annealing temperature, we vary the concentration of primary amine and hydroxyl groups in PDA, which influences adhesion at the metal/PLA interface. We believe that these findings contribute to optimizing and broadening the applications of PDA in composite materials.</p

Invariance of Charge of Laughlin Quasiparticles

A Quantum Antidot electrometer has been used in the first direct observation of the fractionally quantized electric charge. In this paper we report experiments performed on the integer i = 1, 2 and fractional f = 1/3 quantum Hall plateaus extending over a filling factor range of at least 27%. We find the charge of the Laughlin quasiparticles to be invariantly e/3, with standard deviation of 1.2% and absolute accuracy of 4%, independent of filling, tunneling current, and temperature.Comment: 4 pages, 5 fig

Cross-cultural Adaptation and Validation of Beliefs about Medicines Questionnaire on Asthma and Chronic Obstructive Pulmonary Disease Patients

OBJECTIVES: Inadequate adaptation to long-term treatment of chronic illnesses is the most common reason for the inability to obtain the benefits medications can provide. Treatment compliance is influenced by several factors. Beliefs about Medicines Questionnaire (BMQ) developed by Horne et al. in 1999 to evaluate the cognitive representation of medicines have many validation studies, which resulted in good psychometric properties. The aim of the present study was to evaluate the reliability and validity of the BMQ Turkish translation in patients with asthma and chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS: Fifty asthma and 50 COPD patients participated in this methodological study. The scale was adapted to Turkish through translation, comparison with other language versions, back translation, and a pre-test. The structural validity was assessed using factor analysis. RESULTS: Similar to the original scale, factor analysis confirmed that BMQ had a four-factor structure that accounts for 58.23% of the total variance. The BMQ showed an acceptable internal consistency (Cronbach's alpha coefficient: specific-necessity, 0.832: specific-concerns, 0.722; general-harm, 0.792; and general-overuse, 0.682). The factor analysis revealed the same patterns for all questions between the Turkish and original scales. CONCLUSION: The psychometric properties of the BMQ were consistent with those reported in the original study. We found that the Turkish translation of BMQ is a valid and reliable tool for assessing medicine-related beliefs in patients with asthma and COPD

Magnetoresistance of nondegenerate quantum electron channels formed on the surface of superfluid helium

Transport properties of quasi-one-dimensional nondegenerate quantum wires formed on the surface of liquid helium in the presence of a normal magnetic field are studied using the momentum balance equation method and the memory function formalism. The interaction with both kinds of scatterers available (vapor atoms and capillary wave quanta) is considered. We show that unlike classical wires, quantum nondegenerate channels exhibit strong magnetoresistance which increases with lowering the temperature.Comment: 8 pages, 7 figure

Dephasing Times in a Non-degenerate Two-Dimensional Electron Gas

Studies of weak localization by scattering from vapor atoms for electrons on a liquid helium surface are reported. There are three contributions to the dephasing time. Dephasing by the motion of vapor atoms perpendicular to the surface is studied by varying the holding field to change the characteristic width of the electron layer at the surface. A change in vapor density alters the quasi-elastic scattering length and the dephasing due to the motion of atoms both perpendicular and parallel to the surface. Dephasing due to the electron-electron interaction is dependent on the electron density.Comment: 4 pages, Revte

Global mortality and readmission rates following COPD exacerbation-related hospitalisation: a meta-analysis of 65 945 individual patients

\ua9 2024, European Respiratory Society. All rights reserved.Background Exacerbations of COPD (ECOPD) have a major impact on patients and healthcare systems across the world. Precise estimates of the global burden of ECOPD on mortality and hospital readmission are needed to inform policy makers and aid preventive strategies to mitigate this burden. The aims of the present study were to explore global in-hospital mortality, post-discharge mortality and hospital readmission rates after ECOPD-related hospitalisation using an individual patient data meta-analysis (IPDMA) design. Methods A systematic review was performed identifying studies that reported in-hospital mortality, postdischarge mortality and hospital readmission rates following ECOPD-related hospitalisation. Data analyses were conducted using a one-stage random-effects meta-analysis model. This study was conducted and reported in accordance with the PRISMA-IPD statement. Results Data of 65 945 individual patients with COPD were analysed. The pooled in-hospital mortality rate was 6.2%, pooled 30-, 90- and 365-day post-discharge mortality rates were 1.8%, 5.5% and 10.9%, respectively, and pooled 30-, 90- and 365-day hospital readmission rates were 7.1%, 12.6% and 32.1%, respectively, with noticeable variability between studies and countries. Strongest predictors of mortality and hospital readmission included noninvasive mechanical ventilation and a history of two or more ECOPD-related hospitalisation

ADVANCE integrated group intervention to address both substance use and intimate partner abuse perpetration by men in substance use treatment: a feasibility randomised controlled trial

Background: Substance use is a risk factor for intimate partner abuse (IPA) perpetration. Delivering perpetrator interventions concurrently with substance use treatment shows promise. Methods: The feasibility of conducting an efficacy and cost-effectiveness trial of the ADVANCE 16-week intervention to reduce IPA by men in substance use treatment was explored. A multicentre, parallel group individually randomised controlled feasibility trial and formative evaluation was conducted. Over three temporal cycles, 104 men who had perpetrated IPA towards a female (ex) partner in the past year were randomly allocated to receive the ADVANCE intervention + substance use treatment as usual (TAU) (n = 54) or TAU only (n = 50) and assessed 16-weeks post-randomisation. Participants’ (ex) partners were offered support and 27 provided outcome data. Thirty-one staff and 12 men who attended the intervention participated in focus groups or interviews that were analysed using the framework approach. Pre-specified criteria assessed the feasibility of progression to a definitive trial: 1) ≥ 60% of eligible male participants recruited; 2) intervention acceptable to staff and male participants; 3) ≥ 70% of participants followed-up and 4) levels of substance use and 5) IPA perpetrated by men in the intervention arm did not increase from average baseline level at 16-weeks post-randomisation. Results: 70.7% (104/147) of eligible men were recruited. The formative evaluation confirmed the intervention’s acceptability. Therapeutic alliance and session satisfaction were rated highly. The overall median rate of intervention session attendance (of 14 compulsory sessions) was 28.6% (range 14.3–64.3% by the third cycle). 49.0% (51/104) of men and 63.0% (17/27) of their (ex) partners were followed-up 16-weeks post-randomisation. This increased to 100% of men and women by cycle three. At follow-up, neither substance use nor IPA perpetration had worsened for men in the intervention arm. Conclusions: It was feasible to deliver the ADVANCE intervention in substance use treatment services, although it proved difficult to collect data from female (ex)partners. While some progression criteria were met, others were not, although improvements were demonstrated by the third cycle. Lessons learned will be implemented into the study design for a definitive trial of the ADVANCE intervention

Potential Role of Stabilized Criegee Radicals in Sulfuric Acid Production in a High Biogenic VOC Environment

We present field observations made in June 2011 downwind of Dallas-Fort Worth, TX, and evaluate the role of stabilized Criegee radicals (sCIs) in gaseous sulfuric acid (H2SO4) production. Zero-dimensional model calculations show that sCI from biogenic volatile organic compounds composed the majority of the sCIs. The main uncertainty associated with an evaluation of H2SO4 production from the sCI reaction channel is the lack of experimentally determined reaction rates for sCIs formed from isoprene ozonolysis with SO2 along with systematic discrepancies in experimentally derived reaction rates between other sCIs and SO2 and water vapor. In general, the maximum of H2SO4 production from the sCI channel is found in the late afternoon as ozone increases toward the late afternoon. The sCI channel, however, contributes minor H2SO4 production compared with the conventional OH channel in the mid-day. Finally, the production and the loss rates of H2SO4 are compared. The application of the recommended mass accommodation coefficient causes significant overestimation of H2SO4 loss rates compared with H2SO4 production rates. However, the application of a lower experimental value for the mass accommodation coefficient provides good agreement between the loss and production rates of H2SO4. The results suggest that the recommended coefficient for the H2O surface may not be suitable for this relatively dry environment