196 research outputs found
Two-dimensional simulations of temperature and current-density distribution in electromigrated structures
We report on the application of a feedback-controlled electromigration
technique for the formation of nanometer-sized gaps in mesoscopic gold wires
and rings. The effect of current density and temperature, linked via Joule
heating, on the resulting gap size is investigated. Experimentally, a good
thermal coupling to the substrate turned out to be crucial to reach electrode
spacings below 10 nm and to avoid overall melting of the nanostructures. This
finding is supported by numerical calculations of the current-density and
temperature profiles for structure layouts subjected to electromigration. The
numerical method can be used for optimizing the layout so as to predetermine
the location where electromigation leads to the formation of a gap.Comment: 9 pages, 6 figure
Conceptualizing sustainable consumption: toward an integrative framework
Consumption and sustainability are complex issues—they cannot be reduced to the choice of consumer goods or to “green consumption.” Doing so would neglect the multifaceted embeddedness of consumer acts and the multidimensionality of sustainability. To understand patterns of consumption and move them toward sustainability means dealing with this double complexity. A coherent reference framework is therefore needed, to enable locating and correlating research questions, theories, and findings. Such a framework should provide a basis for interdisciplinary under-standing, mutual acknowledgment, and collaborative knowledge creation. Therefore, it needs to be the result of an integrative approach; otherwise it would not allow a wide variety of disciplines to work with it. This article presents such a framework, developed in the course of an interdisciplinary process in a research program. In this process, the researchers of the focal topic asked four questions: 1) How can consumption be conceptualized? 2) How can consumption and sustainability be related? 3) How can sustainable consumption be assessed? and 4) How can changes to individual consumption be motivated? The article condenses the researchers’ overall answers to these questions into four complementary core statements capturing the key elements of the reference framework and concludes by sketching the framework’s benefits for future research
The C-terminus of p63 contains multiple regulatory elements with different functions
The transcription factor p63 is expressed as at least six different isoforms, of which two have been assigned critical biological roles within ectodermal development and skin stem cell biology on the one hand and supervision of the genetic stability of oocytes on the other hand. These two isoforms contain a C-terminal inhibitory domain that negatively regulates their transcriptional activity. This inhibitory domain contains two individual components: one that uses an internal binding mechanism to interact with and mask the transactivation domain and one that is based on sumoylation. We have carried out an extensive alanine scanning study to identify critical regions within the inhibitory domain. These experiments show that a stretch of ~13 amino acids is crucial for the binding function. Further, investigation of transcriptional activity and the intracellular level of mutants that cannot be sumoylated suggests that sumoylation reduces the concentration of p63. We therefore propose that the inhibitory function of the C-terminal domain is in part due to direct inhibition of the transcriptional activity of the protein and in part due to indirect inhibition by controlling the concentration of p63. Keywords: p63, transcriptional regulation, auto-inhibition, sumoylatio
Elektrogesponnene Polymerfasern als neuartiges Material für die Bioelektrokatalyse des Enzyms Pyrrolochinolinchinon-abhängige Glucosedehydrogenase
Es wurde ein dreidimensionales Polymerfasernetzwerk aufgebaut, charakterisiert und anschließend daran das Enzym Pyrrolochinolinchinon-abhängige Glukosedehydrogenase (PQQ)GDH gebunden. Das Polymerfasernetzwerk wurde durch Elektrospinnen einer Mischung des Polymers Polyacrylnitril und verschiedener leitfähiger Polymere der Polyanilin-Familie auf Indium-Zinn-Oxid-Elektroden aufgebracht. Die so hergestellten Fasermatten erwiesen sich bei mikroskopischen Untersuchungen gleichförmig präpariert und die Faserdurchmesser bewegten sich im Bereich weniger hundert Nanometer. Das Redoxpaar Kaliumhexacyanoferrat (II/III) zeigte an diesen Polymer-Elektrodenstrukturen eine quasi-reversible Elektrochemie. Bei weitergehenden Untersuchungen an den enzymmodifizierten Fasern ((PQQ)GDH) konnten unter Substratzugabe (Glukose) bioelektrokatalytische Ströme nachgewiesen werden. Das Fasernetzwerk fungiert hier nicht nur als Immobilisierungsmatrix, sondern als auch als Teil des Signalwandlers.A three-dimensional polymeric electrode structure was developed, characterized and subsequently coupled with the enzyme pyrroloquinoline quinone-dependent Glucosedehydrogenase (PQQ)GDH. The polymeric fiber network is produced by means of electrospinning from mixtures of polyacrylonitrile (PAN) and three different sulfonated poylanilines on top of ITO electrodes. The mats are uniform in their overall appearance; average diameters of the fibers produced are in the range of a few hundred nanometers. These polymeric structures can be shown to allow electrochemical conversions as verified with the ferri-/ferrocyanide redox couple. In addition, application in bioelectrocatalysis can be demonstrated. For two of three selected blends of PAN with sulfonated polyanillines, a well-defined bioelectrochemical response is obtained upon covalent fixation of PQQ-GDH to the fiber network and subsequent addition of substrate glucose. The electrospun matrix does not only act here as an immobilization support, but at the same time as a transducing element
Towards a novel bioelectrocatalytic platform based on "wiring" of pyrroloquinoline quinone-dependent glucose dehydrogenase with an electrospun conductive polymeric fiber architecture
Electrospinning is known as a fabrication technique for electrode architectures that serve as immobilization matrices for biomolecules. The current work demonstrates a novel approach to construct a conductive polymeric platform, capable not only of immobilization, but also of electrical connection of the biomolecule with the electrode. It is produced upon electrospinning from mixtures of three different highly conductive sulfonated polyanilines and polyacrylonitrile on ITO electrodes. The resulting fiber mats are with a well-retained conductivity. After coupling the enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) to polymeric structures and addition of the substrate glucose an efficient bioelectrocatalysis is demonstrated. Depending on the choice of the sulfonated polyanilline mediatorless bioelectrocatalysis starts at low potentials;no large overpotential is needed to drive the reaction. Thus, the electrospun conductive immobilization matrix acts here as a transducing element, representing a promising strategy to use 3D polymeric scaffolds as wiring agents for active enzymes. In addition, the mild and well reproducible fabrication process and the active role of the polymer film in withdrawing electrons from the reduced PQQ-GDH lead to a system with high stability. This could provide access to a larger group of enzymes for bioelectrochemical applications including biosensors and biofuel cells
Feasibility, Adherence, and Effectiveness of Blended Psychotherapy for Severe Mental Illnesses: Scoping Review
Background
Blended psychotherapy (bPT) combines face-to-face psychotherapy with digital interventions to enhance the effectiveness of mental health treatment. The feasibility and effectiveness of bPT have been demonstrated for various mental health issues, although primarily for patients with higher levels of functioning.
Objective
This scoping review aims to investigate the feasibility, adherence, and effectiveness of bPT for the treatment of patients with severe mental illnesses (SMIs).
Methods
Following the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) guidelines, we conducted searches in PubMed, MEDLINE, Embase, PsycINFO, and PsycArticles for studies published until March 23, 2023.
Results
Out of 587 screened papers, we incorporated 25 studies encompassing 23 bPT interventions, involving a total of 2554 patients with SMI. The intervention formats and research designs exhibited significant variation. Our findings offer preliminary evidence supporting the feasibility of bPT for SMI, although there is limited research on adherence. Nevertheless, the summarized studies indicated promising attrition rates, spanning from 0% to 37%, implying a potential beneficial impact of bPT on adherence to SMI treatment. The quantity of evidence on the effects of bPT for SMI was limited and challenging to generalize. Among the 15 controlled trials, 4 concluded that bPT interventions were effective compared with controls. However, it is noteworthy that 2 of these studies used the same study population, and the control groups exhibited significant variations.
Conclusions
Overall, our review suggests that while bPT appears promising as a treatment method, further research is necessary to establish its effectiveness for SMI. We discuss considerations for clinical implementation, directions, and future research
Investigating the effect of a nap following experimental trauma on analogue PTSD symptoms
Cognitive models assume that the incomplete integration of a traumatic experience into the autobiographical memory results in typical symptoms associated with post-traumatic stress disorder (PTSD) such as intrusive re-experiencing. Sleep supports the integration of new experiences into existing memory networks through memory consolidation. In fifty-six females, we investigated whether a 90-min daytime nap (n = 33) compared to a wake period (n = 23) after being exposed to an experimental trauma (i.e. a trauma film) prevents PTSD analogue symptoms. Intrusive memories were recorded for seven days using a diary, overall PTSD symptoms were assessed using the Impact of Event Scale (IES-R) and affective response to trauma cues were measured one week after experimental trauma. The two groups did not differ in any of the analogue PTSD symptoms. However, participants obtaining rapid eye movement (REM) sleep in the nap experienced less distressing intrusive memories. Moreover, the duration of REM sleep and slow wave activity was negatively correlated with analogue PTSD symptoms. Our findings suggest that even a short sleep period after experimental trauma can play a protective role in trauma memory formation but only if the nap contains REM sleep. Our data provide additional evidence for a critical role of REM sleep in PTSD development
Effects of current treatments for trauma survivors with posttraumatic stress disorder on reducing a negative self-concept: a systematic review and meta-analysis
Background: A negative self-concept is characterised by dysfunctional cognitions about the self and has been suggested to be a key factor involved in the development and maintenance of posttraumatic stress disorder (PTSD). In addition, the current definitions of PTSD according to DSM-5 and the new ICD-11 diagnosis of Complex PTSD (CPTSD) include aspects of negative self-concept in their diagnostic criteria.
Objective: The aim of this meta-analysis was to synthesise the currently available evidence on the effects of psychological interventions for PTSD on negative self-concept.
Methods: PubMed, PsychINFO, PSYNDEX, PTSDpubs and Cochrane Library were searched for randomised controlled trials (RCTs) of psychological treatments for PTSD symptoms in adults, published up to February 2021. A systematic review and meta-analysis were conducted, with risk of bias assessed by the Cochrane Risk of Bias Assessment Tool.
Results: A total of 25 RCTs (N = 2585) were included in the meta-analysis. Results showed that psychological interventions significantly improve a negative self-concept with a moderate to large controlled effect size (k = 30, g = 0.67, 95% CI [0.31, 1.02], p < .001) at post-treatment. Heterogeneity between studies was large but could not be accounted for by moderators included in the current analysis, i.e. different types of interventions (e.g. with vs. without a cognitive restructuring component, trauma-focused vs. not).
Conclusions: Current treatments for PTSD are effective in reducing a negative self-concept. However, more research is needed to identify moderators of this effect and identify interventions that are most effective for reducing negative self-concept
Nanoscale Magnetic Imaging using Circularly Polarized High-Harmonic Radiation
This work demonstrates nanoscale magnetic imaging using bright circularly
polarized high-harmonic radiation. We utilize the magneto-optical contrast of
worm-like magnetic domains in a Co/Pd multilayer structure, obtaining
quantitative amplitude and phase maps by lensless imaging. A
diffraction-limited spatial resolution of 49 nm is achieved with iterative
phase reconstruction enhanced by a holographic mask. Harnessing the unique
coherence of high harmonics, this approach will facilitate quantitative,
element-specific and spatially-resolved studies of ultrafast magnetization
dynamics, advancing both fundamental and applied aspects of nanoscale
magnetism.Comment: Ofer Kfir and Sergey Zayko contributed equally to this work.
Presented in CLEO 2017 (Oral) doi.org/10.1364/CLEO_QELS.2017.FW1H.
Zum Einfluss der Darstellung von Rollenvorbildern auf die Mensch-Technik-Interaktion im demografischen Wandel
Die selbstständige Lebensführung bis in das hohe Alter ist eines der Hauptziele der alternden Gesellschaft. Erwägungen älterer Menschen fallen hier mit zentralen Forderungen der Politik zusammen. Eine Schlüsselrolle spielt dabei die Mensch-Technik-Interaktion im demografischen Wandel (MTIDW). Der Beitrag stellt erste Ergebnisse des Projekts "Silver Clips" vor, mit dem an der Hochschule Harz (HS Harz) die Darstellung von Rollenvorbildern zur Heranführung Älterer an die MTIDW optimiert werden soll
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