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The conducting state of a quasi-two-dimensional electron gas (q2DEG), formed at the heterointerface between the two wide-bandgap insulators LaAlO₃ (LAO) and SrTiO₃, can be made completely insulating by low-energy, 150-eV, Ar⁺ irradiation. The metallic behavior of the interface can be recovered by high-temperature oxygen annealing. The electrical transport properties of the recovered q2DEG are exactly the same as before the irradiation. Microstructural investigations confirm that the transition is not due to physical etching or crystal lattice distortion of the LAO film below its critical thickness. They also reveal a correlation between electrical state, LAO film surface amorphization, and argon ion implantation. The experimental results are in agreement with density functional theory calculations of Ar implantation and migration in the LAO film. This suggests that the metal-insulator transition may be caused by charge trapping in the defect amorphous layer created during the ion irradiation.

It is commonly assumed that algorithmic curation of search results creates filter bubbles, where users’ beliefs are continually reinforced and opposing views are suppressed. However, empirical evidence has failed to support this hypothesis. Instead, it has been suggested that filter bubbles may result from individuals engaging selectively with information in search engine results pages. However, this “self-imposed filter bubble hypothesis” has remained empirically untested. In this study, we find support for the hypothesis using eye-tracking technology and link selection data. We presented partisan participants (n = 48) with sets of simulated Google Search results, controlling for the ideological leaning of each link. Participants spent more time viewing own-side links than other links (p = .037). In our sample, participants who identified as right-wing exhibited a greater such bias than those that identified as left wing (p < .001). In addition, we found that both liberals and conservatives tended to select own-side links (p < .001). Finally, there was a significant effect of trust, such that links associated with less trusted sources were attended less and selected less often by liberals and conservatives alike (p < .001). Our study challenges the efficacy of policies that aim at combatting filter bubbles by presenting users with an ideologically diverse set of search results., QC 20230515

The increasingly complex context of dynamic, high-tempo military air operations raise new needs for aircraft maintenance and logistic support systems to more rapidly respond to changes in operational needs and available resources, with retained support resource efficiency. The future maintenance and support system are thus envisioned with improved net-centric capabilities to facilitate matching of tactical needs with aircraft maintenance capabilities. The study addresses this challenge by creating abstract representations and definitions of relevant tactical structures and maintenance structures, processes, and resources using enterprise modelling. By addressing this in a holistic perspective, a better understanding of the matching problem is achieved, enabling efficient matching of operational needs with available resources. Based on these findings, graph models are created from a domain-centric view of two adjacent domain contexts, which includes command and control and aircraft maintenance contexts. The result has the ability to leverage interoperability and collaboration between air- and ground-based systems by facilitating interactions between tactical needs and aircraft maintenance resources.

This work presents an approach for information exchange between adjacent air operations domains by means of graph technologies. The approach has the ability to leverage interoperability and collaboration between air- and ground-based systems and stakeholders in respective domains. In its foundation, it provides a means for relevant actors to access and assess relevant data, information and knowledge, and thus provide input in terms of viable action alternatives in a complex and dynamic operational context. As a proof-of-concept, we have utilized a full-stack application framework to implement a decision support demonstrator for operational aircraft maintenance. Our solution facilitates a lightweight and dynamic representation of relevant domain knowledge, readily available for exploitation by graph algorithms, adapted to our domain. We have based our implementation on the full-stack application framework Grand-Stack, which is an architecture designed to exploit the power of graphs throughout its stack. © 2022 ICAS. All Rights Reserved.

Background and aim: In the aftermath of a myocardial infarction with non-obstructive coronary arteries (MINOCA) or Takotsubo syndrome (TS), patients commonly express high levels of stress and anxiety. Current treatment alternatives rarely address these issues. The planned E-health Treatment of Stress and Anxiety in Stockholm Myocardial Infarction With Non-obstructive Coronaries Study (e-SMINC) aims to evaluate the effects of an internet-based intervention, building on cognitive behavioral therapy (CBT) by comparison with treatment as usual using an RCT approach. This was a small-scale single arm study designed to test the feasibility of the RCT, addressing uncertainties regarding recruitment, data collection, and intervention delivery. Methods: Participant recruitment and screening took place before discharge from the coronary care unit at a large Swedish hospital. Eligible patients were invited to a nine-step psychologist guided, internet-based CBT intervention. The sample size was set in advance to 10 participants completing the intervention. The recruitment and flow of participants were documented and evaluated in relation to seven pre-defined progression criteria. Self-reports of anxiety (HADS-A), stress (PSS-14), cardiac anxiety (CAQ), posttraumatic stress (IES-6) and quality of life (Rand-36), collected at screening, pre-intervention and post-intervention, were analysed descriptively and by effect sizes (Cohen's d). Individual interviews targeting participant experiences were conducted. Results: Six out of seven progression criteria yielded no concerns. Out of 49 patients with a working diagnosis of MINOCA or TS, 31 were eligible for screening, 26 consented to participate, and 14 were eligible with regard to symptoms of stress and/or anxiety. Eleven completed the pre-assessment and were given access the intervention, and 9 completed the intervention. Only the number of patients screened prior to eligibility assessment was slightly lower than expected, indicati

Background: In the aftermath of a myocardial infarction with non-obstructive coronary arteries (MINOCA) or Takotsubo syndrome (TS), patients commonly express high levels of stress and anxiety. Current treatment alternatives rarely address these issues. Methods: The study is a randomised controlled trial, where 90 patients with a discharge diagnosis of MINOCA or TS who also report symptoms of stress or anxiety will be randomised 2–6 weeks after their cardiac event. The treatment consists of 10 weeks of Internet-based cognitive behaviour therapy (CBT) and starts immediately after randomisation for the treatment group. The control group receives usual care. Main outcomes are symptoms of anxiety measured with the Hospital Anxiety and Depression scale, anxiety subscale, and perceived stress measured with the Perceived Stress Scale, 14-item version, 10 weeks after randomisation. Secondary measures include cardiac specific anxiety, symptoms of post-traumatic stress, quality of life, cortisol measured in hair and physiological stress responses (heart rate variability, blood pressure and saliva cortisol) during a stress procedure. Ten weeks after randomisation, the control group will also receive treatment. Long-term follow-up in the self-report measures mentioned above will be conducted 20 and 50 weeks after randomisation where the total group’s development over time is followed, and the groups receiving intervention early versus late compared. Discussion: At present, there are no randomised studies evaluating psychological treatment for patients with MINOCA or TS. There is an urgent need for treatment alternatives aiming at relieving stress and anxiety considering the high mental stress and anxiety levels observed in MINOCA and TS, leading to decreased quality of life. CBT aiming at reducing mental stress has been shown to be effective regarding prognosis in patients with coronary artery disease. The current protocol describes a randomised open-label controlled trial evalu

The increasingly complex context of dynamic, high-tempo military air operations raises new needs for airbase aircraft maintenance and logistic support systems to more rapidly respond to changes in operational needs, with retained support resource efficiency. The future maintenance and support system are thus envisioned with improved net-centric capabilities to facilitate matching of tactical needs with aircraft maintenance capabilities. Today military Command and Control (C2) of tactical needs against airbase aircraft maintenance capabilities contain many manual activities. This constrains speed of execution as well as drives manning requirements, and there is a need to further develop existing IS and IT support. Thus the studied matching capability address these limitations through an approach based on improved integration of the air vehicle on-board health management system with corresponding ground-based functions, and exploitation of technologies such as big-data analytics, diagnostic-prognostics, Artificial Intelligence (AI), machine learning and reasoning systems in a system-of-system-wide service architecture. However, understanding the concept of matching of tactical needs and aircraft maintenance capabilities requires insights of complex multi-domain C2 interactions and interrelations between the tactical domain and the aircraft maintenance domain. Whereas each domain is quite well understood, the more detailed interrelations between the domains is less studied. This paper present an approach to this problem by creating useful representations of the underpinning insights, by enterprise modeling of abstract representations and definitions of relevant tactical and maintenance structures, processes, and resources, in the airbase context, to better understand the matching problem, and to address this problem through a holistic perspective.

Phase-separated polymer films are commonly used as coatings around pharmaceutical oral dosage forms (tablets or pellets) to facilitate controlled drug release. A typical choice is to use ethyl cellulose and hydroxypropyl cellulose (EC/HPC) polymer blends. When an EC/HPC film is in contact with water, the leaching out of the water-soluble HPC phase produces an EC film with a porous network through which the drug is transported. The drug release can be tailored by controlling the structure of this porous network. Imaging and characterization of such EC porous films facilitates understanding of how to control and tailor film formation and ultimately drug release. Combined focused ion beam and scanning electron microscope (FIB-SEM) tomography is a well-established technique for high-resolution imaging, and suitable for this application. However, for segmenting image data, in this case to correctly identify the porous network, FIB-SEM is a challenging technique to work with. In this work, we implement convolutional neural networks for segmentation of FIB-SEM image data. The data are acquired from three EC porous films where the HPC phases have been leached out. The three data sets have varying porosities in a range of interest for controlled drug release applications. We demonstrate very good agreement with manual segmentations. In particular, we demonstrate an improvement in comparison to previous work on the same data sets that utilized a random forest classifier trained on Gaussian scale-space features. Finally, we facilitate further development of FIB-SEM segmentation methods by making the data and software used open access., QC 20220216

Polar polythiophenes with oligoethylene glycol side chains are exceedingly soft materials. A low glass transition temperature and low degree of crystallinity prevents their use as a bulk material. The synthesis of a copolymer comprising 1) soft polythiophene blocks with tetraethylene glycol side chains, and 2) hard urethane segments is reported. The molecular design is contrary to that of other semiconductor-insulator copolymers, which typically combine a soft nonconjugated spacer with hard conjugated segments. Copolymerization of polar polythiophenes and urethane segments results in a ductile material that can be used as a free-standing solid. The copolymer displays a storage modulus of 25 MPa at room temperature, elongation at break of 95%, and a reduced degree of swelling due to hydrogen bonding. Both chemical doping and electrochemical oxidation reveal that the introduction of urethane segments does not unduly reduce the hole charge-carrier mobility and ability to take up charge. Further, stable operation is observed when the copolymer is used as the active layer of organic electrochemical transistors., QC 20210409