Amidst the growing prevalence of chronic stress and its potential negative impacts on mental health, this review explores the use of virtual reality (VR) as a stress management solution, aiming to assess its viability and effectiveness in this context. A comprehensive search was conducted on MEDLINE, PsycINFO, and Embase from inception until February 2024. Eligible studies were primary research papers that focused on the use of VR as an intervention to mitigate psychological stress and/or distress. We included studies where the assessment of stress levels primarily relied on self-report measures. A total of 50 studies involving 2885 participants were included in our systematic review. VR-based interventions varied across studies, implementing tools such as cognitive behavioural therapy, exposure therapy, mindfulness and relaxation, repetition tasks, and psychoeducation. The reviewed studies yielded mixed results; however, a strong indication was present in highlighting the promising potential of VR-based interventions. Many studies observed a decrease in psychiatric symptoms in participants and reported increased quality of life. Various studies also found VR to be a valuable tool in promoting stress reduction and relaxation. VR was proven useful in exposing participants to stressors in a safe, controlled way. These potential benefits appear to come with no risk of harm to the participants. Although the findings are heterogenous, there is sufficient evidence supporting the use of VR for stress management across a range of contexts and populations. Overall, VR appears to be a generally low-risk, feasible intervention for those struggling with stress.

Skin-to-skin relaxation is offered by one of the department\'s psychomotor therapists, within a precise framework of clearly defined indications and contraindications. The aim of this intervention modality is to support the parent-baby relationship in a context of vulnerability. A self-questionnaire for parents was used to take stock of the practice of skin-to-skin relaxation at the Centre Hospitalier Intercommunal de Créteil. The use of this mediation appears beneficial and deserves to be developed in neonatology.

Dog ownership has been linked to numerous benefits to human health and wellbeing. However, due to the lack of previous research on changes to brain activity during interactions with pet dogs, the underlying psychophysiological mechanisms are still unclear. The aim of the present study was to examine changes in heart rate (HR), heart rate variability (HRV), and electroencephalogram (EEG) power during interactions between dog owners and their pet dog. Fifty healthy adult dog owners completed baseline psychological measures and pet attachment scales. Subjective units of relaxation (SUR) as well as continuous EEG, HR, and HRV via portable devices were measured during five experimental conditions (baseline resting, relaxation-induction exercise, patting a toy dog, real dog present, and patting a real dog) in participants\' homes. SUR was higher in all experimental conditions than at baseline. SUR was also higher during dog interaction than when the dog was present with no interaction. However, SUR during dog interaction was not significantly different from the toy dog and relaxation induction condition. Higher delta, theta, alpha, beta power and HR were found during dog interaction than all other conditions. Higher HRV was found during dog interaction compared to baseline, patting a toy dog, and relaxation-induction exercise, but not significantly different from the real dog present only condition. Lastly, overall HR correlated with psychological measures. Overall, the results show that there are significant changes in brain and heart activity when humans interact with pet dogs, consistent with increases in relaxation and focussed attention. These findings are relevant to understanding the potential mechanisms for health benefits associated with pets.

Superparamagnetic iron oxide nanoparticles (SPIOs) are used as tracers in Magnetic Particle Imaging (MPI). It is crucial to understand the magnetic properties of SPIOs for optimizing MPI imaging contrast, resolution, and sensitivity. Brownian and Néel relaxation theory developed in the early 1950s posits that relaxation times can vary with particle size, shell thickness, medium viscosity, and the applied field strength. Magnetic relaxation can soon provide a unique imaging capability, the ability to distinguish bound from unbound MPI tracers in vivo. Yet experimental validation of these theories has not been completed. In this paper, a novel method of pulsed magnetic field relaxometry is used to directly probe the relaxation behavior of superparamagnetic magnetite nanoparticles over a spectrum of magnetic field amplitudes, providing the first experimental validation of theoretical relaxation models. It is also shown that closed-form approximations generated in the early 1970s accurately match both data and numerical Fokker Planck computational models, which are computationally burdensome. This means researchers can trust these approximations for future modeling. All the findings can be translated to sinusoidal excitations used in conventional MPI scanning trajectories.

When individuals are exposed to two pure tones with close frequencies presented separately in each ear, they perceive a third sound known as binaural beats (BB), characterized by a frequency equal to the difference between the two tones. Previous research has suggested that BB may influence brain activity, potentially benefiting attention and relaxation. In this study, we hypothesized that the impact of BB on cognition and EEG is linked to the spatial characteristics of the sound. Participants listened to various types of spatially moving sounds (BB, panning and alternate beeps) at 6Hz and 40Hz frequencies. EEG measurements were conducted throughout the auditory stimulation, and participants completed questionnaires on relaxation, affect, and a sustained attention task. The results indicated that binaural, panning sounds and alternate beeps had a more pronounced effect on electrical brain activity than the control condition. Additionally, an improvement in relaxation was observed with these sounds at both 6Hz and 40Hz. Overall, these findings support our hypothesis that the impact of auditory stimulation lies in the spatial attributes rather than the sensation of beating itself.

OBJECTIVE: This paper investigates the critical role of material thickness in freeze-dried pellets for enhancing the storage stability of encapsulated bacteria. Freeze dried material of varying thicknesses obtained from different annealing durations is quantified using Scanning Electron Microscopy (SEM) and X-ray microtomography (μCT), the material thickness is then correlated to the storage stability of the encapsulated cells.
METHODS: A formulation comprising of sucrose, maltodextrin, and probiotic cells is quenched in liquid nitrogen to form pellets. The pellets undergo different durations of annealing before undergoing freeze-drying. The material thickness is quantified using SEM and μCT. Storage stability in both oxygen-rich and oxygen-poor environments is evaluated by measuring CFU counts and correlated with the pellet structure.
RESULTS: The varying annealing protocols produce a range of material thicknesses, with more extensive annealing resulting in thicker materials. Storage stability exhibits a positive correlation with material thickness, indicating improved stability with thicker materials. Non-annealed pellets exhibit structural irregularities and inconsistent storage stability, highlighting the impracticality of avoiding annealing in the freeze-drying process.
CONCLUSIONS: Extensive annealing not only enhances the storage stability of probiotic products but also provides greater control over the freeze-drying process, ensuring homogeneous and reproducible products. This study underscores the importance of material thickness in freeze-dried pellets for optimizing storage stability for probiotic formulations, and emphasize the necessity of annealing as a critical step in freeze-drying quenched pellets to achieve desired structural and stability outcomes.

Nitroxides are stable organic radicals with exceptionally long lifetimes, which render them uniquely suitable as observable probes or polarising agents for spectroscopic investigation of biomolecular structure and dynamics. Radical-based probes for biological applications are ideally characterized by both robustness towards reductive degradation and beneficial electron spin relaxation parameters. These properties are largely influenced by the molecular structure of the nitroxide scaffold, and also by the conformations it prefers to adopt. In this study we present the synthesis of the first nitroxides based on a spirocyclic pyrrolidine scaffold with an exocyclic methylene substituent. The conformations adopted by these nitroxides were evaluated by X-ray crystallography, both with single nitroxide crystals and by inclusion of nitroxides in a microporous crystalline sponge. The kinetic and thermodynamic stability of the new nitroxides towards reduction was investigated by electron paramagnetic resonance (EPR) spectroscopy and cyclic voltammetry (CV). In combination with EPR measurements of electron spin relaxation properties, these results suggest that this new family of nitroxides can provide access to multifunctionalized probes and polarising agents suitable for use in biological environments at elevated temperatures.

OBJECTIVE: To examine the effects of six relaxation techniques on perceived momentary relaxation and a possible association of relaxation effects with time and practice experience in people with cancer.
METHODS: We used data from participants with cancer in a larger study practicing app-based relaxation techniques over 10 weeks, assessed momentary relaxation before and after every third relaxation practice, and analyzed momentary relaxation changes with a linear mixed-effects model.
RESULTS: The sample included 611 before-after observations from 91 participants (70 females (76.9%)) with a mean age of 55.43 years (SD 10.88). We found moderate evidence for variations in momentary relaxation changes across different techniques (P = .026), with short meditation, mindfulness meditation, guided imagery, and progressive muscle relaxation more frequently observed and leading to more relaxation than body scan and walking meditation. Furthermore, we found moderate evidence for increasing momentary relaxation changes over time (P = .046), but no evidence for an association between momentary relaxation and the number of previous observations (proxy for practice experience; P = .47).
CONCLUSIONS: We compared six app-based relaxation techniques in a real-life setting of people with cancer. The observed variations in perceived momentary relaxation appear to correspond with the popularity of the techniques used: The most popular relaxation techniques were the most effective and the least popular were the least effective. The effects increased over time, likely caused by dropout of individuals who gained no immediate benefit. Our findings open an interesting avenue for future research to better understand which relaxation techniques work best for whom in which situations.
BACKGROUND: DRKS00027546; https://drks.de/search/en/trial/DRKS00027546.

The positive impact of essential oils (EOs) on stress release has been demonstrated in both humans and dogs. Among the EOs known for their anxiety-reducing properties, including Cananga odorata, Citrus aurantium, Cupressus sempervirens, Lavandula angustifolia, and Litsea citrata, there is a lack of consensus on the optimal concentration for efficacy. This exploratory study sought to investigate the effects of olfactory enrichment with a blend of these EOs on dogs introduced to an unfamiliar environment. The authors sought to determine the minimum concentration required to achieve increased relaxation. In a randomized controlled crossover study design, 54 dogs were exposed to 0, 1, 5, and 10 drops of the EO blend applied to their collars before entering an unfamiliar room with their owners. Behavioral observations were employed to quantify the total duration of activity and relaxation related behaviours for each dog under each treatment condition. A significant difference in panting was identified among the treatments (χ2(3) = 9.88; p = 0.020). Dunn-Bonferroni post-hoc tests revealed a significant reduction in panting during the 10 drops treatment compared to the control treatment (p = 0.047). No significant differences were observed for other behaviors. To provide a comprehensive overview of behavioral tendencies in this canine population, owners also completed the Canine Behavioral Assessment and Research Questionnaire (C-BARQ), revealing low scores for anxiety in the study group. These preliminary findings suggest that a concentration of 10 drops of the EO blend on a dog\'s collar induces increased relaxation, specifically reflected in decreased panting behavior. Lower concentrations did not exhibit a significant relationship with the observed behaviors. These initial findings underscore the importance of exposing dogs to an appropriate concentration of EOs when exploring their potential benefits on welfare among dogs with low anxiety levels. Further research in this area is crucial for a comprehensive understanding of the potential benefits of EOs for canine welfare.

Highly varying process conditions drive polymers into nonequilibrium molecular conformations. This has direct implications for the resulting structural and mechanical properties. This study rigorously investigated processing-property relations from a microscopic perspective. The corresponding models use a mesoscale molecular dynamics (MD) approach. Different loading conditions, including uniaxial and biaxial stretching, along with various cooling conditions, were employed to mimic process conditions on the micro-scale. The resulting intricate interplay between equi-biaxial stretching, orientation, and crystallization behavior in long polyethylene chains was reviewed. The study reveals notable effects depending on different cooling and biaxial stretching procedures. The findings emphasize the significance of considering distributions and directions of chain ordering. Local inspections of trajectories unveil that crystal growth predominantly occurs in regions devoid of entanglements.