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This study advances the vibration-assisted welding (VAW) technique for joining medium-carbon, low-alloy steels, which are typically challenging to weld. Traditional welding methods suggest low linear energy and mandatory pre- and post-heating due to these steels' poor weldability. However, VAW employs a vibrating table to maintain part vibration throughout the automatic MIG/MAG welding process. This study tested the VAW technique on 42CrMo4 steel samples, achieving satisfactory weld quality without the need for pre- and post-heating treatments. This research revealed that while vibration frequencies between 550 Hz and 9.5 kHz minimally affect the appearance of the weld joint, the oscillation acceleration has a significant impact. The acceleration along the weld axis (ax), combined with the welding speed and vibration frequency, affects the weld surface's appearance, particularly its scaly texture and size. Lateral acceleration (ay) alters the seam width, whereas vertical acceleration (az) affects penetration depth at the root. Notably, if the effective acceleration (aef) surpasses 40 m/s2, there is a risk of molten metal expulsion from the weld pool or piercing at the joint's base. The quality of the joints was assessed through macroscopic and microscopic structural analyses, micro-hardness tests in the weld zone, and bending trials. The mechanical properties of the VAW samples were found to be acceptable, with hardness slightly exceeding that of the samples subjected to pre- and post-heating. Moreover, the VAW process significantly reduced energy consumption and operational time. The employed vibration system, with a power rating of 100 W, operates for just a few minutes, resulting in substantially lower energy usage compared to the traditional pre- and post-heating method, which typically requires a 5 kW electric furnace.
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In principle, after all manufacturing processes are performed, a set of residual stresses occur in the product that have their particular distribution given the manufacturing process performed. The residual stresses must be removed to achieve the desired dimensional accuracy and quality. Among stress-relieving processes performed for a piece following the manufacturing process, we can refer to thermal and vibratory stress relief (VSR). Both methods perform the same function as they enter a part or all of a piece into the plastic phase, causing a fracture of residual stresses to be released with local plastic deformations. The process is as follows: The stress induced by thermal or vibratory loads is added to the residual stresses and exceeds the yield stress. This research, which is focused on VSR, aims to evaluate the effect of the main parameters of the VSR method, including load amplitude or amount, load application frequency, and cycle numbers. The general trend of the problem is that the VSR process is performed for a piece with residual stress, and the effect of the abovementioned parameters on reducing its residual stresses is evaluated.
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This paper presents geometric analyses of welded frames after free relaxing and vibratory stress relief (VSR). The tested frames were components of a prototype packaging machine. Two types of relaxation were carried out to remove stresses introduced as a result of the welding process. One of the frames was subjected to free relaxation, while the other one was subjected to accelerated vibration relaxation. Detection of the frame geometry changes was performed using a photogrammetric system. In addition, an evaluation of the geometry change was conducted for fifteen variants of a steel frame support. A comparative analysis of the geometric deviations of the frames after free and vibratory stress relief confirmed the assumption that the frame post vibration stress relief better reproduces the nominal dimensions. Nevertheless, it should be emphasized that after vibratory stress relief, the frame is not subject to further deformation, which is a desirable effect. In the case of free relaxing, the frame undergoes dimensional changes in a random manner. In summary, carrying out accelerated vibratory stress relief allows for control of spontaneous dimensional changes in the designed frame of a packaging machine resulting from spontaneous relaxation of stresses arising from the welding process. The shortening of the relaxation process of the welded frame is also an unquestionable advantage.
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Video gamers can play to negate the psychological impact of stress, which may become problematic when users over-rely on the stress relief potential of gaming. This study used a repeated measures experimental design to investigate the relationships between stress, video gaming, and problematic video gaming behaviours in a convenience sample of 40 students at a UK university. The results indicated that positive affect increased and negative affect decreased, whilst a biological stress measure (instantaneous pulse rate) also decreased after a short video gaming session (t(36) = 4.82, p < 0.001, d = 0.79). The results also suggested that video gaming can act as a short-term buffer against the physiological impact of stress. Further research should focus on testing individuals who have been tested for gaming disorder, as opposed to the general population. Research could also utilise variations of the methodological framework used in this study to examine the intensity of a stress relief effect under different social situations. The study's findings in relation to published works are also discussed.
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This study experimentally investigated electrically assisted (EA) stress relief annealing for cold-coiled commercial automotive springs. In EA stress relief annealing, the temperature of a spring is rapidly increased to the annealing temperature (400 °C) and is held constant for a specified time using a pulsed electric current. Experimental findings show that the effectiveness of the EA stress relief annealing is superior to that of the conventional stress relief annealing, especially in terms of process time. The present study suggests that EA stress relief annealing, with properly selected process parameters, can effectively substitute for time-consuming conventional stress relief annealing using a furnace for cold-coiled automotive springs.
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Scalmalloy® is an Al-Mg-Sc-Zr-based alloy specifically developed for additive manufacturing (AM). This alloy is designed for use with a direct aging treatment, as recommended by the manufacturer, rather than with a multistep treatment, as often seen in conventional manufacturing. Most work with Scalmalloy® is conducted using powder bed rather than powder-fed processes. This investigation seeks to fill this knowledge gap and expand beyond single-step aging to promote an overall balanced AM-fabricated component. For this study, directed energy deposition (DED)-fabricated Scalmalloy® components were subjected to low-temperature treatments to minimize residual stresses inherent in the material due to the layer-by-layer build process. X-ray diffraction (XRD) indicated the possibility of stress minimization while reducing the detriment to mechanical strength through lower temperature treatments. Microstructural analyses consisting of energy dispersion spectroscopy (EDS) and electron backscatter diffraction (EBSD) revealed the presence of grain growth detrimentally affecting the strength and elongation made possible by very small grains inherent to AM and rapid solidification. Tensile testing determined that treatment at 175 °C for 1 h provides the best relief from the existing residual stresses; however, this is accompanied by a diminishment in the yield and tensile strength of 19 and 9.5%, respectively. It is noted that treatment at 175 °C for 2 h did not provide as great of a decrease in residual stresses, theorized to be the result of grain growth and other strengthening mechanisms further stressing the structure; however, the residual stresses are still significantly diminished compared with the as-built condition. Furthermore, a minimal reduction of the tensile strengths indicates the possibility of finding a balance between property diminishment and stress state through the work proposed here.
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The commercialization of alloy-type anodes has been hindered by rapid capacity degradation due to volume fluctuations. To address this issue, stress-relief engineering is proposed for Si anodes that combines hierarchical nanoporous structures and modified layers, inspired by the phenomenon in which structures with continuous changes in curvature can reduce stress concentration. The N-doped C-modified hierarchical nanoporous Si anode with a microcurved pore wall (N-C@m-HNP Si) is prepared from inexpensive Mg-55Si alloys using a simple chemical etching and heat treatment process. When used as the anode for lithium-ion batteries, the N-C@m-HNP Si anode exhibits initial charge/discharge specific capacities of 1092.93 and 2636.32 mAh g-1 at 0.1 C (1 C = 3579 mA g-1), respectively, and a stable reversible specific capacity of 1071.84 mAh g-1 after 200 cycles. The synergy of the hierarchical porous structure with a microcurved pore wall and the N-doped C-modified layer effectively improves the electrochemical performance of N-C@m-HNP Si, and the effectiveness of stress-relief engineering is quantitatively analyzed through the theory of elastic bending of thin plates. Moreover, the formation process of Li15Si4 crystals, which causes substantial mechanical stress, is investigated using first-principles molecular dynamic simulations to reveal their tendency to occur at different scales. The results demonstrate that the hierarchical nanoporous structure helps to inhibit the transformation of amorphous LixSi into metastable Li15Si4 crystals during lithiation.
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This manuscript examines using serenity rooms and similar tools to improve the workplace during COVID-19 for nurses and other practitioners. A rapid review of the literature was conducted and completed from four different databases, including PubMed, CINAHL, Science Direct, and Academic Search Complete. The literature review was completed with the use of a single-string Boolean search to maximize the number of articles returned. The resulting 14 germane articles yielded six facilitator themes and four barrier themes. Facilitator themes included: benefits, assistive adjuncts, places of relaxation, leadership required, availability, and other effects. Barrier themes included: lacking leadership, concerns regarding lack of space, holistic concerns, and negative perceptions. There is a significant lack of research in the literature in this area. Most of the literature reviewed showed widely positive results for institutions that utilized serenity rooms or similar tools for decreasing nurse and practitioner stress and burnout. The use of these tools improved nurse and practitioner compassion, retention, and resiliency.
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The link between subjective well-being (SWB) and forest visits is increasingly driving the development and preservation of restorative forest environments in numerous countries. However, there is limited knowledge regarding the effect of people's preferences for forest patterns and activities on this connection. Here we investigated whether associations exist between the preferences for certain forest features and activities, and the SWB increase and stress reduction in response to forest visits. A nationwide digital survey was administered to a representative sample of the Slovak population. The recollection-based data obtained from one thousand respondents were analysed through agglomerative clustering and ordinal regression. The analyses revealed that improved SWB and stress reduction were associated with preferences for uneven-aged forests, forest smell, as well as recreational, but not provisioning forest activities. The respective interrelationships explained up to 20% of SWB increase and stress reduction after forest visits. The results suggest that recollection-based study findings can be generalized for real-world forests and that forest management can contribute to the well-being of forest visitors by shaping the diversity of woodlands and their sensory experiences.
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Florestas , Humanos , Idoso , Eslováquia , Inquéritos e QuestionáriosRESUMO
Background and objectives: This study's primary objective is to investigate the impact of art-making on the mental well-being of college students, who often experience heightened stress during their initial university years. Methods: Employing a comprehensive methodology, combining interviews and the Perceived Stress Scale (PSS), the research aimed to assess whether a four-week art-making intervention can effectively alleviate stress levels among college students. In the experimental group, participants engaged in a variety of art-making activities, including freehand drawing, clay modeling, and crafting. Results: The results revealed that, in the pre-test, there were no significant differences between the experimental and control groups for each assessed indicator. However, in the post-test, significant differences emerged across all indicators. Further analysis demonstrated a significant reduction in stress perception among the experimental group participants between the pre-test and post-test phases. Conclusion: In conclusion, this study provides compelling evidence that art-making has the potential to foster positive personal development and significantly reduce stress levels among college students.
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The abundant oxygen-related defects (e.g., O vacancies, O-H) in the TiO2 electron transport layer results in high surface energy, which is detrimental to effective carrier extraction and seriously impairs the photovoltaic performance and stability of perovskite solar cells. Here, novel surface energy engineering (SEE) is developed by applying a surfactant of heptadecafluorooctanesulfonate tetraethylammonium (HFSTA) on the surface of the TiO2 . Theoretical calculations show that the HFSTA-TiO2 is less prone to form O vacancies, leading to lower surface energy, thus improving the carrier-extraction efficiency. The experimental results show that superior perovskite film is obtained due to the reduced heterogeneous nucleation sites and improved crystallization process on the modified TiO2 . Furthermore, the flexible long alkyl chains in HFSTA considerably relieve the compressive stresses at the buried interface. By combining the passivation of TiO2 , crystallization process modulation, and stress relief, a champion PCE up to 25.03% is achieved. The device without encapsulation sustains 92.2% of its initial PCE after more than 2500 h storage under air ambient with relative humidity of 25-30%. The SEE of a buried interface paves a new way toward high-efficiency, stable perovskite solar cells.
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High levels of stress and burnout, low help-seeking behaviour and unhealthy coping in healthcare professionals (HCPs), are a critical concern globally. Mindfulness-based interventions (MBIs) reduce stress, are a healthy coping mechanism and have become increasingly popular among HCPs, especially during the Covid-19 pandemic. Nevertheless, HCPs' busy schedules require the intervention to be accessible, pragmatic, and context specific. Key to this goal is approaching mindfulness from a multicultural perspective, especially in diverse settings such as Africa. This paper aims to provide practical tips to ensure that the MBI offered is effective with multicultural HCPs during intense stress. Four tips each discuss the curriculum, implementation, and sustainability, respectively. The tips are elucidated by practical examples of regulating stress in healthcare settings and to offer a guideline to help structure future MBIs to be culturally and context appropriate.
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Esgotamento Profissional , Atenção Plena , Humanos , Pandemias , Atenção à Saúde , Esgotamento Profissional/prevenção & controle , Pessoal de SaúdeRESUMO
Purpose: Emotional stress is a precipitating factor for Graves disease (GD). However, the influence of stress relief on the course of GD is unknown. Here, we present a series of patients diagnosed with stress-induced GD in whom stress relief alone led to remission of GD. Cases: We report on 11 patients in whom hyperthyroid symptoms started just after severe emotional stress. All patients had suppressed thyroid-stimulating hormone (TSH) levels and elevated free thyroxine (FT4; 22.2-49.5â pmol/L) and TSH-receptor antibody (TRAb; 0.57-40â U/L) levels and were subsequently diagnosed with stress-induced GD. However, all patients declined antithyroid drug treatment. Surprisingly, clinical and biochemical remission was observed in 9 out of 11 patients after 1 to 3 and 2 to 7 months of self-reported stress relief, respectively. Five patients showed long-lasting remission (median follow-up 2.3 years). In 4 patients, remission was initially achieved, but GD relapsed 1 to 4 years afterwards. In 2 patients, treatment with antithyroid drugs was initiated because of rapidly increasing FT4 levels. Baseline FT4 and TRAb levels tended to be higher in patients who did not achieve remission. Furthermore, patients without long-lasting remission were more frequently known to have prior thyroid disease. Conclusion: We report on a series of patients with stress-induced GD in whom stress relief alone led to remission of GD (thus without antithyroid drugs). This may indicate that clinicians could consider stopping antithyroid drug treatment or at least shortening the treatment period after stress relief in patients with stress-induced GD.
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Further improvement of the performance and stability of inverted perovskite solar cells (PSCs) is necessary for commercialization. Here, ferrocene derivative dibenzoylferrocene (DBzFe) is used as an additive to enhance the performance and stability of MA- and Br- free PSCs. The results show that the introduction of DBzFe not only passivates the defects in the film but also inhibits the ion migration in the film. The final device achieves a power conversion efficiency (PCE) of 23.53%, which is one of the highest efficiencies currently based on self-assembled monolayers (SAMs). Moreover, it maintains more than 96.4% of the original efficiency when running continuously for 400 h at the maximum power point.
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Relief, the appetitive state after the termination of aversive stimuli, is evolutionarily conserved. Understanding the behavioral role of this well-conserved phenomenon and its underlying neurobiological mechanisms are open and important questions. Here, we discover that the magnitude of relief from physical stress strongly correlates with individual resilience to depression-like behaviors in chronic stressed mice. Notably, blocking stress relief causes vulnerability to depression-like behaviors, whereas natural rewards supplied shortly after stress promotes resilience. Stress relief is mediated by reward-related mesolimbic dopamine neurons, which show minute-long, persistent activation after stress termination. Circuitry-wise, activation or inhibition of circuits downstream of the ventral tegmental area during the transient relief period bi-directionally regulates depression resilience. These results reveal an evolutionary function of stress relief in depression resilience and identify the neural substrate mediating this effect. Importantly, our data suggest a behavioral strategy of augmenting positive valence of stress relief with natural rewards to prevent depression.
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Núcleo Accumbens , Resiliência Psicológica , Camundongos , Animais , Núcleo Accumbens/fisiologia , Depressão , Área Tegmentar Ventral/fisiologia , RecompensaRESUMO
INTRODUCTION: Although the longest efficacy record, some patients report about urinary leakage during higher intra-abdominal pressure after Artificial Urinary Sphincter (AUS) implantation. To improve the continent results, we placed in addition to the occluding cuff and the pressure regulating balloon, in a second procedure a stress-relief reservoir in lower abdomen, for additional passive pressure transmission to the occluding cuff. METHODS: In this retrospective monocentric data analysis between 2011 and 2018, 80 patients with persistence incontinence after AUS implantation were included. Stress-relief reservoir was indicated in 12 patients with involuntary leakage of urine, that occurred when intra-abdominal pressure raised. RESULTS: In all 12 cases, the stress reservoir was easily implanted and there were no intraoperative complications. In a mean follow-up time of 53 months, the pad per day usage (p/d) improved from 3 (± 1.2) to 1.7 (± 1.5) (p = 0.001). Two patients with multiple previous abdominal surgeries used an equal number of pads after SRR; however, an improvement during physical exertion was reported. Continence situation was evaluated with a questionnaire and was rated as "excellent", "good", or "satisfactory" by 11 (92%) patients. CONCLUSION: The persistence of urinary incontinence after AUS is a challenging topic. Implantation of a stress reservoir in carefully selected patients with urinary leakage during higher intra-abdominal pressure is minimally invasive and offers new options to improve the proven long-term record of AUS. Certainly, more investigations are needed to determine the clinical relevance of this approach.
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Incontinência Urinária por Estresse , Incontinência Urinária , Esfíncter Urinário Artificial , Humanos , Esfíncter Urinário Artificial/efeitos adversos , Resultado do Tratamento , Incontinência Urinária por Estresse/cirurgia , Incontinência Urinária por Estresse/etiologia , Estudos Retrospectivos , Implantação de Prótese/efeitos adversosRESUMO
Introduction: Interacting with animals has been demonstrated to possess the healing benefits to humans. However, there are limitations in physical interaction due to COVID-19 and safety issues. Therefore, as an alternative, we created mixed-reality (MR)-based human-animal interaction (HAI) content and experimentally verified its effect on mental stress reduction. Methods: We created three types of interactive content: observing the movement of a non-reactive virtual cat, interacting with a virtual cat whose responses can be seen, and interacting with a virtual cat whose responses can be both seen and heard. The experiment was performed by 30 healthy young women, and a mental arithmetic task was used to induce mild mental stress before experiencing each content. During the experiment, the subject's electrocardiogram was continuously recorded, and the psychological state was evaluated through a questionnaire. Results: The results showed that MR-based virtual cat content significantly reduces mental stress and induces positive emotions after stressful situations. In particular, when the virtual cat provided audiovisual feedback, the activation amount of the parasympathetic nervous system and the increase of positive emotions were the greatest. Discussion: Based on this encouraging research result, this method should be further investigated to see if it can replace real HAI for human mental health management.
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[This corrects the article DOI: 10.3389/fpls.2022.1025974.].
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BACKGROUND: Electronic nicotine delivery systems (ENDS) continue to be popular among young adults. These devices are often advertised as a healthy alternative to quitting tobacco cigarettes. However, young adults represent a population who view it as a novel behavior that provides a sense of popularity, social acceptance, and desired physiologic properties. The objective of this study was to examine characteristics of vaping behavior among college students and explore possible associations between groups of vaping behavior (stopped, initiated, increased, decreased, stayed the same). METHODS: In a multi-center cross-sectional study, 656 students from University of Tampa in the United States and University of Applied Sciences in Germany (IST) were recruited to answer a 31-item online questionnaire. A chi-square test was used to evaluate associations between the groups. RESULTS: Prevalence rates indicated approximately 31% of all students were currently using ENDS. Even though more negative than positive experiences with ENDS were reported, most students stated their vaping increased during COVID-19 lockdowns. Addiction and stress relief emerged to be predictors (P < .001) of an increase in vaping, whereas social motives were not statistically significant. Living situation (P = .63) and depression (P = .10) were not significantly associated with vaping behavior. CONCLUSIONS: ENDS products continue to yield very high levels of nicotine creating addiction in young adults. Addiction counseling and evidenced-based practices should be employed at every level (individual, community, and school). Additionally, mental health counseling for students in pandemic and high-stress environments may help to combat stress in a more proactive manner than self-medicating.
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COVID-19 , Sistemas Eletrônicos de Liberação de Nicotina , Tabagismo , Vaping , Humanos , Adulto Jovem , Estados Unidos , Vaping/epidemiologia , Vaping/psicologia , Pandemias , Estudos Transversais , COVID-19/epidemiologia , Controle de Doenças TransmissíveisRESUMO
OBJECTIVES: Humour is an integral part of communication and often used in education to support learning, build relationships, lessen stress, and create a positive environment. This paper presents results from an integrative review of literature that aimed to explore how humour is used in nursing education. DESIGN: Integrative literature review. DATA SOURCES: CINAHL, INFORMIT, Medline and Proquest education. REVIEW METHODS: An integrative review of published research was conducted in the above-mentioned databases during March to June 2022. A hand search in reference lists of published articles was also conducted. Search terms followed PEO (population, exposure and outcome) and included 'Faculty, Nursing', 'Nurse* Student*', 'Baccalaureate', 'Humo?r', 'Laugh*', 'Wit', 'Fun*', 'Comedy', 'Educat*', 'Teach*', 'Learn*' and 'Curricul*'. Inclusion criteria stated articles must have a research component investigating how humour is used and received by students in nursing education. The articles were peer reviewed and published after 2001. Conference abstracts, editorials and articles describing the use of humour in nursing education without research evidence were excluded. Grey literature was not included. RESULTS: The search yielded two hundred and one articles, 10 of which met the inclusion criteria. Studies were primarily qualitative (n = 9) with 1 quantitative study. Five themes were found among the articles (1) Humour builds social relationships (2) Humour aids learning/critical thinking (3) Humour and stress relief (4) Humour to focus attention and (5) Negative use of humour. CONCLUSION: Findings suggest that the use of humour in nursing education lowers stress, improves attention, increases focus and improved information retention. However, findings also conclude that negative humour is not conducive to learning. Research is needed to explore the use of humour in nurse education in order to develop teaching approaches that include culturally sensitive humour to enhance the student learning experience and reduce stress.