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Exploring the mental health impact of COVID-19 on parents of young children: anxiety, depression, and contributing factors
No full textBackground
The COVID-19 pandemic led to a global shutdown, with most countries implementing widespread lockdowns. While such measures were essential in curbing the spread of COVID-19, their impact on the mental health of parents with preschool-aged children is not yet sufficiently understood. This study aimed to assess anxiety and depression symptoms in parents during and after the COVID-19 lockdowns, and to examine how demographic and pandemic-related factors influenced these outcomes.
Method
A sample of 128 parents in Germany with preschool children (aged 2 to 6 years) participated in an online survey. The survey assessed three key periods: before the nationwide lockdowns (retrospectively), during the most challenging phase of the lockdown (retrospectively), and after the lockdowns were lifted. Symptoms of depression and anxiety were investigated with validated questionnaires and pandemic-specific stressors (e.g., isolation of child) with a self-developed set of 23 items. Descriptive statistics, group comparisons, and hierarchical multiple regression analyses were conducted.
Results
Symptoms of anxiety and depression significantly increased during lockdowns in comparison to before pandemic onset and remained elevated after restrictions eased. Key predictors of poorer mental health included pre-pandemic symptoms, lower parental education, concerns about access to primary care, and children's social isolation during lockdowns. Demographic factors alone were not consistently significant predictors.
Conclusions
Symptoms of anxiety and depression significantly increased during lockdowns compared to before pandemic onset and remained elevated after restrictions eased. COVID-19-related stressors played a greater role in parental mental health outcomes than demographic variables. These findings emphasize the need for early identification of at-risk families and the development of targeted interventions to support parental well-being in future public health emergencies
Super-Resolution Contrast-Enhanced Ultrasound Examination Down to the Microvasculature Enables Quantitative Analysis of Liver Lesions: First Results
No full textThis article investigates the first use of dynamic microvascularization of liver lesions in clinical evaluation using real-time super-resolution contrast-enhanced ultrasound (SR CEUS). A retrospective analysis of SR CEUS examinations of liver lesions was performed. All examinations were conducted using an SC7-1U convex probe after the bolus injection of the ultrasound contrast agent. Digital cine loops were stored for independent evaluation. The evaluation was performed with respect to parallel measuring lines (the diameter corresponded to the capillary density) in the area of the reference lesion, liver tissue, and liver capsule using statistical analysis. In total, 65 patients (female n = 28; male n = 37; average age 57.8 ± 17.2 years) were evaluated. The examined liver lesions were mostly benign masses (n = 46). Mild liver fibrosis (stage F1) was present in most cases (n = 35). The lesions examined were located at an average tissue depth of 6.07 ± 2.47 cm. The highest number of lesion measurements was observed in the malignant lesion group. Significant differences in the measurements were found when comparing benign lesions with the capillary region (p < 0.001) and normal liver tissue (p < 0.01). The use of SR CEUS opens up new possibilities for the quantification of neovascularization, assessment of microvascular changes, and evaluation of the follow-up of intrahepatic interventions
Does collaborative remembering serve a directive function? Examining the influence of collaborative remembering on subsequent decision making
No full textRemembering together with others can facilitate memory for previously encountered contents, but can also prompt social contagion with information not previously encountered. This study examined whether these effects of collaborative remembering might serve a directive function and guide subsequent individual decisions. Participants were tested in groups of three and completed an adapted version of a prisoner’s dilemma. They initially encountered faces of different players on a screen, who cooperated with them or acted as cheaters. Some of these players were encountered by all three participants, others by single participants only. An interpolated memory test on all players was completed individually or collaboratively. During a final decision game, participants were asked to decide whether to cooperate with each player or not. Three experiments were conducted, which additionally varied encoding, the retention interval before the interpolated memory test, and format and instructions for the interpolated memory test. The results consistently showed adaptive decision making. Participants were more likely to cooperate with players who had previously cooperated with them, relative to both new players and cheaters. Interpolated collaborative remembering had no benefit, however—neither for decisions toward directly encountered players nor for decisions toward players encountered by other participants. Effects of collaborative remembering may thus not serve a directive function and guide future behavior, or at least they may not do so in this adapted version of a prisoner’s dilemma
Penetrationen des Hirnschädels mit festen Fremdkörpern. Inzidenz, klinischer Verlauf und Outcome an der neurochirurgischen Klinik des Universitätsklinikums Regensburg von 1999-2019
No full text1. Ziel
Nicht-militärische, niedrigenergetische penetrierende Hirnverletzungen sind in der Bevölkerung entwickelter Länder selten, stellen jedoch auch in großen neurochirurgischen Zentren ein erhebliches klinisches Problem dar. Grund dafür sind das Fehlen evidenzbasierter Empfehlungen sowie die hohe Variabilität individueller Traumamuster. Derartige Verletzungen verursachen erhebliche primäre und sekundäre Schäden des Hirnparenchyms, wobei insbesondere Spätkomplikationen wie Infektionen oder vaskuläre Läsionen das Outcome maßgeblich beeinflussen können. Da Studien zu diesem Thema nur spärlich vorhanden sind, wollten wir mit einer der größten Fallserien Europas zur Erweiterung der wissenschaftlichen Datenlage beitragen und unsere klinischen Erfahrungen darstellen. Im Fokus standen dabei insbesondere:
-Epidemiologie und Traumamechanismus
-Art und Zeitpunkt der Diagnosestellung
-Behandlungsstrategien
-Management von Komplikationen
-Outcome
2.Methoden
Bei der vorliegenden Arbeit handelt es sich um eine retrospektive Datenanalyse von Patienten, die zwischen 1999 und 2019 an dem Universitätsklinikum Regensburg behandelt wurden und Kriterien für die Diagnose einer penetrierenden Hirnverletzung erfüllten. Das Outcome wurde anhand der Skalen GOS und mRS bewertet. Die Ergebnisse wurden mit der verfügbaren Literatur verglichen.
3.Ergebnisse
In die Studie wurden 13 Patienten eingeschlossen (Durchschnittsalter 46 Jahre, überwiegend männlich, zwei Kinder). Die häufigsten Ursachen waren Freizeitunfälle und Stürze. Am häufigsten erfolgte die Penetration über die Orbita. Initial wurden CCT und CTA durchgeführt. Bei Verdacht auf einen hölzernen Fremdkörper kam zusätzlich die MRT zum Einsatz. Alle Patienten wurden operativ versorgt. Ein Patient entwickelte eine vaskuläre Komplikation (Dissektion der A. carotis interna) und musste radiologisch-interventionell behandelt werden. Die maximale Nachbeobachtungszeit betrug 7 Jahre.
4.Schlussfolgerung
Das Gesamtergebnis in unserer Patientengruppe war insgesamt günstig. Eine adäquate, zeitnahe Versorgung sowie eine enge interdisziplinäre Zusammenarbeit sind entscheidend. Die Rolle der Angiographie wurde diskutiert. Bezüglich des therapeutischen Vorgehens bevorzugten wir eine frühzeitige operative Entfernung des Fremdkörpers sowie ggf. eine Blutstillung. Postoperativ ist eine engmaschige Überwachung auf entzündliche und vaskuläre Komplikationen essenziell
Quantum transport in topological insulator HgTe point contacts
No full textThis thesis describes quantum transport in HgTe 3D topological insulator quantum point contacts (QPCs). The main focus is on the study of transport properties of point contacts with different dimensions and characteristic conductances ranging from 1 to 100 e^2/h, subjected to quantizing magnetic fields in perpendicular direction to the sample plane. An appropriate model to describe the essential physics of conductance and transmission at a quantum point contact was developed. All investigated QPCs showed no conductance quantization in zero magnetic field, regardless of their conductance value.
The observed steps are characterized by anomalous, non-integer conductance values that persist over a wide range of magnetic fields, gate voltages, and temperatures, suggesting an underlying preferred scattering mechanism within the QPCs. Analysis of the transport response of macroscopic regions of the sample suggests that the QPC conductance largely reflects the properties of the adjacent 2D regions. This is evident from the fact that, for a given magnetic field and gate voltage, the step number matches the filling factor of the two-dimensional electrons or holes. In this case, the QPC acts as a selective filter that partially transmits the edge states, as observed in quantum Hall measurements. The constancy of the transmission coefficient of this filter is a striking and unusual result, atypical for one-dimensional systems. The occurrence of the anomalous conductance steps was reproduced by numerical tight-binding calculations based on an effective model for a 2D electron conduction band, as well as by an extended Landauer-Büttiker model.
The devices consistently fell into two groups with distinct conductance step sequences, roughly correlated with the QPC cross section, although random electrostatic potentials introduced significant variations. However, the grouping could be reliably predicted from the conductance at zero magnetic field. For larger point contacts, the conductance behavior transitioned from step-like to oscillation-like patterns, resembling Shubnikov–de Haas oscillations.
Furthermore, the effect of a tilted magnetic field was studied by keeping the perpendicular magnetic field component constant while varying the parallel component relative to the wire axis. A parity effect in the sequence of conductance steps was observed in the valence band, with every second step disappearing at high tilted magnetic fields. A quantitative analysis of the effect demonstrated that agreement with the experimental data can only be achieved by introducing a Zeeman splitting that exceeds the cyclotron energy in a perpendicular magnetic field, which is significantly higher than that observed in classical 2DEG/2DHG systems
The influence of persona and conversational task on social interactions with a LLM-controlled embodied conversational agent
Get PDFLarge Language Models (LLMs) have demonstrated remarkable capabilities in conversational tasks. Embodying an LLM as a virtual human allows users to engage in face-to-face social interactions in Virtual Reality. However, the influence of person- and task-related factors in social interactions with LLM-controlled agents remains unclear. In this study, forty-six participants interacted with a virtual agent whose persona was manipulated as “extravert” or “introvert” in three different conversational tasks (small talk, knowledge test, convincing). Social-evaluation, emotional experience, and realism were assessed using ratings. Interactive engagement was measured by quantifying participants' words and conversational turns. Finally, we measured participants’ willingness to ask the agent for help during the knowledge test. Our findings show that the extraverted agent was more positively evaluated, elicited a more pleasant experience and greater engagement, and was assessed as more realistic compared to the introverted agent. Whereas persona did not affect the tendency to ask for help, participants were generally more confident in the answer when they had help of the LLM. Variation of personality traits of LLM-controlled embodied virtual agents, therefore, affects social-emotional processing and behavior in virtual interactions. Embodied virtual agents allow the presentation of naturalistic social encounters in a virtual environment
Electron Spin Resonance at the Single‐Molecule Scale
Get PDFElectron spin resonance (ESR) is a widely employed spectroscopic technique for studying systems with unpaired electron spins, such as molecular radicals. Typically, many billions of spins are required to get a detectable ESR signal, which is subject to extensive ensemble averaging. Downscaling ESR to a single molecule allows studying the signatures of each individual molecule separately, applicable to biomolecules in their native environment, for example. Single-molecule ESR offers several novel research avenues, such as in quantum sensing with a single molecule. Over the last decades, four different single-molecule ESR approaches have been developed, which rely on either optically detected magnetic resonance or scanning-probe microscopy. An introduction into these four approaches including their deployment in pioneering works will be provided
