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1.
Med Teach ; 46(1): 40-45, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37450669

RESUMO

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.


Assuntos
Esgotamento Profissional , Atenção Plena , Humanos , Pandemias , Atenção à Saúde , Esgotamento Profissional/prevenção & controle , Pessoal de Saúde
2.
Ergonomics ; 66(3): 366-376, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35722776

RESUMO

There are limited studies on monotonous task performance and its relationship with anxiety and stress traits. This study aimed to determine if local cooling exerts physiological effects and positively affects task performance. Ten male participants performed monotonous work for 24 min under control and local cooling conditions. We measured physiological arousal and anxiety using electroencephalography and the State-Trait Anxiety Inventory, respectively. The participants rated their drowsiness, the thermal sensation of the seat and whole-body thermal sensation. Despite the lack of significant differences in physiological arousal, the state anxiety score, which reflects the current stressful situation, was significantly lower in the local cooling condition. Therefore, cooling might help relieve stress during monotonous tasks, without impairing task performance. In addition, individuals with higher state anxiety scores tended to experience a faster increase in their arousal level. Thus, individual anxiety traits may modulate attentional resources during monotonous task performance.Practitioner summary: The study on topic related to monotonous task performance and its relationship with anxiety and stress traits is novel. Minimising negative emotions is key to monotonous task execution under stress. Individual anxiety might modulate resource allocation for monotonous task execution.


Assuntos
Ansiedade , Análise e Desempenho de Tarefas , Humanos , Masculino , Ansiedade/psicologia , Vigília/fisiologia , Nível de Alerta/fisiologia , Atenção
3.
Sensors (Basel) ; 22(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35161904

RESUMO

Human-animal interaction (HAI) has been observed to effectively reduce stress and induce positive emotions owing to the process of directly petting and interacting with animals. Interaction with virtual animals has recently emerged as an alternative due to the limitations in general physical interactions, both due to the COVID-19 pandemic and, more generally, due to the difficulties involved in providing adequate care for animals. This study proposes mixed reality (MR)-based human-animal interaction content along with presenting the experimental verification of its effect on the reduction of mental stress. A mental arithmetic task was employed to induce acute mental stress, which was followed by either MR content, in which a participant interacted with virtual animals via gestures and voice commands, or a slide show of animal images. During the experiment, an electrocardiogram (ECG) was continuously recorded with a patch-type, wireless ECG sensor on the chest of the subject, and their psychological state was evaluated with the help of questionnaires after each task. The findings of the study demonstrate that the MR-based interaction with virtual animals significantly reduces mental stress and induces positive emotions. We expect that this study could provide a basis for the widespread use of MR-based content in the field of mental health.


Assuntos
Realidade Aumentada , COVID-19 , Realidade Virtual , Humanos , Pandemias , SARS-CoV-2
4.
Nano Lett ; 20(3): 1526-1535, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31990561

RESUMO

Recent advanced studies on flexible and stretchable electronic devices and optoelectronics have made possible a variety of soft and more functional electronic devices. With consumer demand for highly functional or free-form displays, high flexibility and stretchability in light-emitting devices are needed. Herein, we developed a unique structure of stretchable substrates with pillar arrays to reduce the stress on the active area of devices when strain is applied. We confirmed the advantages of the produced structures using mechanical simulation tools and determined that the structures effectively lessen the applied stress of interconnection as well as the active area in a stretched state. With this stress-relief stretchable substrate, we realized stretchable OLEDs that are compliant and maintain their performance under high strain deformation. Also, devices can be stretched in the biaxis, which is superior to only one-directional stretchable electronics; as such, devices can be used in practical applications like wearable electronics and health monitoring systems. We propose, for the first time, stretchable OLEDs patterned by the thermal evaporation fabrication process onto stress-relief substrates. These OLEDs can mitigate certain problems in previous studies of stretchable OLEDs without need to find new materials or to use a prestrained fabrication process.

5.
Mater Des ; 2092021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36937330

RESUMO

High-throughput experiments that use combinatorial samples with rapid measurements can be used to provide process-structure-property information at reduced time, cost, and effort. Developing these tools and methods is essential in additive manufacturing where new process-structure-property information is required on a frequent basis as advances are made in feedstock materials, additive machines, and post-processing. Here we demonstrate the design and use of combinatorial samples produced on a commercial laser powder bed fusion system to study 60 distinct process conditions of nickel superalloy 625: five laser powers and four laser scan speeds in three different conditions. Combinatorial samples were characterized using optical and electron microscopy, x-ray diffraction, and indentation to estimate the porosity, grain size, crystallographic texture, secondary phase precipitation, and hardness. Indentation and porosity results were compared against a regular sample. The smaller-sized regions (3 mm × 4 mm) in the combinatorial sample have a lower hardness compared to a larger regular sample (20 mm × 20 mm) with similar porosity (< 0.03 %). Despite this difference, meaningful trends were identified with the combinatorial sample for grain size, crystallographic texture, and porosity versus laser power and scan speed as well as trends with hardness versus stress-relief condition.

6.
Orthopade ; 46(7): 610-616, 2017 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-28364351

RESUMO

BACKGROUND: In osteotomies with larger correction angles, the capacity for elastic deformation is frequently exceeded, resulting in plastic deformation and fracture of the opposite cortex, which may lead to subsequent loss of correction. An anteroposterior drill hole at the apex of the horizontal osteotomy (= hinge) is supposed to increase the capacity of the bony hinge for elastic deformation and ideally to prevent fractures of the opposite cortex. MATERIALS AND METHODS: A high tibial osteotomy (HTO) using standard surgical technique was performed in 20 each of Synbones, Sawbones, and human cadaver tibial specimens. In 10 specimens per group, an additional anteroposterior hinge drilling was performed at the apex of the horizontal osteotomy. All fractures of the opposite cortex were photographically and radiographically documented. All fractures were classified according to fracture types 1-3 of the Takeuchi classification. RESULTS: Regardless of the study group, all tibial bones with an additional hinge drilling achieved larger correction angles during the spreading of the wedge until a fracture of the opposite cortex occurred. The average correction angle of all specimens without the drill hole was 2.7°, which increased to 4.8° with the hinge drill (increase by 77.8%). In correction angles exceeding 5°, all specimen showed a hinge fracture regardless of the presence or absence of a hinge drill. CONCLUSIONS: The hinge-protecting effect is restricted to small correction angles, i. e., to unload cartilage repair regions in the absence of severe malalignment. For the treatment of varus gonarthrosis, there is no fracture-protecting effect from a hinge drill.


Assuntos
Osso Cortical/lesões , Complicações Intraoperatórias/prevenção & controle , Traumatismos do Joelho/prevenção & controle , Articulação do Joelho/cirurgia , Osteotomia/métodos , Tíbia/cirurgia , Fraturas da Tíbia/prevenção & controle , Osso Cortical/diagnóstico por imagem , Humanos , Complicações Intraoperatórias/diagnóstico por imagem , Traumatismos do Joelho/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Fatores de Risco , Tíbia/diagnóstico por imagem , Tíbia/lesões , Fraturas da Tíbia/diagnóstico por imagem
7.
Vestn Oftalmol ; 133(4): 31-36, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28980563

RESUMO

AIM: To determine the effect of drug-induced stress-relief tests on biomechanical properties of the ocular fibrous tunic in eyes with early, moderate, or advanced primary open-angle glaucoma (POAG). MATERIAL AND METHODS: A total of 202 eyes of 150 patients with POAG of different severity (early, moderate, or advanced) and 36 eyes of 30 healthy controls were examined. The mean patient age was 62±8.2 years. All groups were standardized by age, sex, and the range of corneal-compensated intraocular pressure (IOP) at baseline (21-30 mmHg). All patients underwent a standard ophthalmic examination, including visometry, biomicroscopy, gonioscopy, ophthalmoscopy, and Humphrey visual field assessment. Corneal hysteresis (CH), corneal resistance factor (CRF), CH-CRF difference, corneal-compensated IOP (IOPcc), and Goldmann-related IOP (IOPg) were measured with Ocular Response Analyzer (ORA, Reichert, USA). The axial eye length was measured on an ultrasonic A-scan (Ocuscan RxP, Alcon, USA) in the 10 MHz mode. RESULTS: CH and CRF variability analysis was conducted to assess changes in biomechanical properties of the fibrous tunic due to an IOP decrease and a tendency toward compensation. For the first time, the ratio between CH and CRF changes (ΔCH/ΔCRF) was used to evaluate biomechanical properties of the fibrous tunic. This ratio provides understanding of the significance of CH and CRF changes after reduction of IOP. In early glaucoma patients, it differed inconsiderably from the control group (p>0.05) and averaged 1.62±0.9. In moderate glaucoma, CH changes were more pronounced than those of CRF: ΔCH/ΔCRF - 2.03±2.41 (under conservative treatment) and 2.12±1.07 (without treatment). In advanced glaucoma an opposite pattern was observed: the CH/CRF ratio got closer to 1.0 largely due to CRF changes, while CH changes became much less pronounced (or even negative, in some cases): ΔCH/ΔCRF - 0.27±0.32 (under conservative treatment), 0.16±1.29 (without treatment). CONCLUSION: While the IOP decreased as a result of drug-induced stress-relief tests, CH and CRF changes differed between the groups depending on the stage of POAG. In early and moderate glaucoma, CH undergoes greater changes than CRF. In advanced glaucoma, CRF changes are more pronounced, and, hence, the ΔCH/ΔCRF ratio shifts reliably as glaucoma progresses. The ratio has also been shown to depend on the duration of the disease and on whether or not eye drops were prescribed.


Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Pressão Intraocular/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Tiofenos/administração & dosagem , Timolol/administração & dosagem , Idoso , Anti-Hipertensivos/administração & dosagem , Fenômenos Biomecânicos , Técnicas de Diagnóstico Oftalmológico , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Glaucoma de Ângulo Aberto/terapia , Gonioscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas/administração & dosagem , Oftalmoscopia/métodos , Gravidade do Paciente , Tonometria Ocular/métodos , Testes de Campo Visual/métodos
8.
3D Print Addit Manuf ; 11(4): 1523-1532, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39360146

RESUMO

The poor surface finish of as-printed (AP) laser powder bed fusion (L-PBF) 316L stainless steels has detrimental impacts on the resulting fatigue and corrosion performance. One postprocessing method, a self-terminating etching process (STEP), can improve the surface finish of parts up to 76%, but the resulting effects on fatigue life and corrosion reliability remain unknown. This work evaluates the effect of the STEP on the fatigue and corrosion performance of L-PBF 316L. In addition, to determine the influence of changing the microstructures from the as-built condition, specimens having undergone a pre-STEP stress relief (SR + STEP) heat treatment and a pre-STEP solution anneal (SA + STEP) were evaluated. The results showed that a pre-STEP SR resulted in the best Sa roughness, while a pre-STEP SA had the biggest improvement in Sv roughness. Despite Sv roughness being a major indicator of fatigue performance, the coarse grains and internal porosity in the SA specimens resulted in the poorest fatigue performance. The SR + STEP specimens' fatigue lives were 10 × higher than the AP samples under a load of 275 MPa and 2-3 × higher under a 350 MPa load. The SR + STEP specimen also had the best corrosion performance in a sodium chloride electrolyte due to the smoother surface and least remnant surface carbides.

9.
Materials (Basel) ; 17(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38793456

RESUMO

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.

10.
Front Psychol ; 15: 1324415, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38356766

RESUMO

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.

11.
Adv Mater ; 36(2): e2306724, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37863645

RESUMO

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.

12.
Heliyon ; 10(11): e32052, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38873681

RESUMO

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.

13.
Healthcare (Basel) ; 12(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38610194

RESUMO

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.

14.
Materials (Basel) ; 17(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673130

RESUMO

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.

15.
Healthcare (Basel) ; 12(16)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39201225

RESUMO

This study aimed to investigate the effects of prolonged inhalation of nature-derived odors indoors on humans. Twenty-six women participated in this study. Heart rate variability, heart rate, blood pressure, pulse rate, estradiol, testosterone, and cortisol were used as indicators of autonomic nervous system and endocrine system activities. Profile of mood state, state-trait anxiety inventory, menopause rating scale and general sleep disturbance scale were used as psychological indicators. The order was as follows: After the participants relaxed in a chair for 5 min, their heart rate variability and heart rate were measured for 3 min with their eyes closed. Subsequently, blood pressure and pulse rate were measured, salivary samples were collected for estradiol, testosterone, and cortisol analyses, and a subjective assessment was conducted. The participants received a diffuser containing fir essential oil and were instructed on its usage and precautions. Subsequently, they returned home and inhaled the fir oil for a week. After 7 days, participants revisited the laboratory for posttest measurements, conducted at the same time as the pretest. Prolonged inhalation of the fir essential oil resulted in increased estradiol concentration, decreased systolic and diastolic blood pressure, relief of menopausal symptoms, reduced anxiety levels, improved sleep quality and mood states. Prolonged inhalation of the fir essential oil induced physiological and psychological relaxation on menopausal women.

16.
Materials (Basel) ; 17(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893972

RESUMO

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.

17.
Nurs Rep ; 14(1): 376-389, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38391074

RESUMO

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.

18.
Materials (Basel) ; 17(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38541487

RESUMO

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.

19.
Ambio ; 53(5): 795-807, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38324121

RESUMO

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.


Assuntos
Florestas , Humanos , Idoso , Eslováquia , Inquéritos e Questionários
20.
ACS Appl Mater Interfaces ; 16(10): 12924-12938, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426939

RESUMO

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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