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This study explores the optimal morphology of photochemical hydrogen evolution catalysts in a one-dimensional system. Systematic engineering of metal tips on precisely defined CdSe@CdS dot-in-rods is conducted to exert control over morphology, composition, and both factors. The outcome yields an optimized configuration, a Au-Pt core-shell structure with a rough Pt surface (Au@r-Pt), which exhibits a remarkable fivefold increase in quantum efficiency, reaching 86% at 455 nm and superior hydrogen evolution rates under visible and AM1.5G irradiation conditions with prolonged stability. Kinetic investigations using photoelectrochemical and time-resolved measurements demonstrate a greater extent and extended lifetime of the charge-separated state on the tips as well as rapid water reduction kinetics on high-energy surfaces. This approach sheds light on the critical role of cocatalysts in hybrid photocatalytic systems for achieving high performance.
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Traditional horizontal osteotomies for small and short chins often yield suboptimal results due to limited bone advancement, resulting in deep labiomental folds and heightened bone resorption risks. This study investigates the effectiveness of an innovative inverted V-shaped osteotomy technique in enhancing esthetic outcomes for patients with such chin concerns. Thirty-eight patients who underwent inverted V-shaped osteotomy for recessed chins between January 2018 and June 2022 were included. Excluding cases involving simultaneous mandibular contouring surgery, patients were followed up for a median duration of 1.2±0.5 years. Preoperation and postoperation soft tissue pogonion (Pg') and labiomental fold depth (LMF) changes were measured. IBM SPSS (version 27.0) was used for statistical analysis, with significance defined as P <0.05. Patient satisfaction was assessed using a visual analog scale. Successful advancement genioplasty was performed on all patients without any severe complications. The average change in soft tissue pogonion (Pg') measured 6.2 (1.9) mm, and the mean alteration in labiomental depth was 0.42 (0.4) mm. The procedure achieved a bone to soft tissue movement ratio of 1:0.96. Patient satisfaction was notably high, with a mean VAS score of 8.7. An inverted V-shaped osteotomy enables greater bone advancement for small and short chins, leading to improved esthetic outcomes and offering a mechanically advantageous condition for bone segments.
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Estética , Mentoplastia , Osteotomia , Satisfação do Paciente , Humanos , Feminino , Masculino , Mentoplastia/métodos , Adulto , Queixo/cirurgia , Osteotomia/métodos , Resultado do TratamentoRESUMO
Light detection and ranging (LiDAR) is widely used in autonomous vehicles to obtain precise 3D information about surrounding road environments. However, under bad weather conditions, such as rain, snow, and fog, LiDAR-detection performance is reduced. This effect has hardly been verified in actual road environments. In this study, tests were conducted with different precipitation levels (10, 20, 30, and 40 mm/h) and fog visibilities (50, 100, and 150 m) on actual roads. Square test objects (60 × 60 cm2) made of retroreflective film, aluminum, steel, black sheet, and plastic, commonly used in Korean road traffic signs, were investigated. Number of point clouds (NPC) and intensity (reflection value of points) were selected as LiDAR performance indicators. These indicators decreased with deteriorating weather in order of light rain (10-20 mm/h), weak fog (<150 m), intense rain (30-40 mm/h), and thick fog (≤50 m). Retroreflective film preserved at least 74% of the NPC under clear conditions with intense rain (30-40 mm/h) and thick fog (<50 m). Aluminum and steel showed non-observation for distances of 20-30 m under these conditions. ANOVA and post hoc tests suggested that these performance reductions were statistically significant. Such empirical tests should clarify the LiDAR performance degradation.
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BACKGROUND: Although it has been common to use artificial implant to augment nasal dorsum in Asian rhinoplasty, the demand for not using it is increasing due to the long-term complications of implants. However, if only the tip is raised without raising the dorsum with implant, it is difficult to avoid supratip depression, so it is difficult to obtain good cosmetic results. The authors would like to report good results, performing an augmentation rhinoplasty that raises the supratip area using the nasal septal cartilage without using an implant. METHODS: Septal gap graft was used in 22 patients undergoing nasal tip surgery from January 2019 to April 2021. Septal gap graft refers to a graft that increases the height of the supratip area by using septal cartilage. Firstly, the authors perform a septal extension graft using the septal cartilage, then the authors fix the lower lateral cartilage in an ideal position, and lastly the authors heighten the nasal tip with onlay graft. The height difference between the nasal bone and the nasal tip, is solved by placing the septal cartilage. Before, during and after surgery, photometric analysis was done by taking clinical pictures. RESULTS: Through the septal gap graft, the supratip depression index was decreased and the nasal tip projection was increased. It was confirmed that the septal gap graft was well maintained at long-term follow-up, and the patients' postoperative satisfaction was also high. CONCLUSIONS: The authors presented a new technique for augmentation rhinoplasty in Asians. Septal gap graft can be used safely and effectively to raise supratip area without using implant.
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Implantes Dentários , Rinoplastia , Humanos , Cartilagens Nasais/cirurgia , Septo Nasal/transplante , Nariz/cirurgia , Estudos Retrospectivos , Rinoplastia/métodosRESUMO
ABSTRACT: Advancement genioplasty is performed to aesthetically improve the lower third of the facial profile. Excessive chin advancement alone may lead to deepened labiomental sulcus and deformed aesthetic results. The purpose of this study was to assess the efficacy of silicone prosthesis placement as an alternative method for effacing an excessively deepened labiomental groove after advancement genioplasty. Three hundred and seventy-six patients underwent genioplasty between January 2014 and October 2017. Among these were 216 cases of advancement genioplasty, of which 79 (62 females and 17 males) underwent advancement procedures using silicone implants. Inserting the silicone implant at the sulcus easily removes the deepened groove. This procedure could be an easy and reliable method for attaining an aesthetically pleasing result in excessive advancement genioplasty.
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Implantes Dentários , Mentoplastia , Queixo/cirurgia , Estética Dentária , Feminino , Humanos , Masculino , SiliconesRESUMO
Recently, the use of quadrotors has increased in numerous applications, such as agriculture, rescue, transportation, inspection, and localization. Time-optimal quadrotor waypoint tracking is defined as controlling quadrotors to follow the given waypoints as quickly as possible. Although PID control is widely used for quadrotor control, it is not adaptable to environmental changes, such as various trajectories and dynamic external disturbances. In this work, we discover that adjusting PID control frequencies is necessary for adapting to environmental changes by showing that the optimal control frequencies can be different for different environments. Therefore, we suggest a method to schedule the PID position and attitude control frequencies for time-optimal quadrotor waypoint tracking. The method includes (1) a Control Frequency Agent (CFA) that finds the best control frequencies in various environments, (2) a Quadrotor Future Predictor (QFP) that predicts the next state of a quadrotor, and (3) combining the CFA and QFP for time-optimal quadrotor waypoint tracking under unknown external disturbances. The experimental results prove the effectiveness of the proposed method by showing that it reduces the travel time of a quadrotor for waypoint tracking.
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Algoritmos , Simulação por ComputadorRESUMO
The performance of LiDAR sensors deteriorates under adverse weather conditions such as rainfall. However, few studies have empirically analyzed this phenomenon. Hence, we investigated differences in sensor data due to environmental changes (distance from objects (road signs), object material, vehicle (sensor) speed, and amount of rainfall) during LiDAR sensing of road facilities. The indicators used to verify the performance of LiDAR were numbers of point cloud (NPC) and intensity. Differences in the indicators were tested through a two-way ANOVA. First, both NPC and intensity increased with decreasing distance. Second, despite some exceptions, changes in speed did not affect the indicators. Third, the values of NPC do not differ depending on the materials and the intensity of each material followed the order aluminum > steel > plastic > wood, although exceptions were found. Fourth, with an increase in rainfall, both indicators decreased for all materials; specifically, under rainfall of 40 mm/h or more, a substantial reduction was observed. These results demonstrate that LiDAR must overcome the challenges posed by inclement weather to be applicable in the production of road facilities that improve the effectiveness of autonomous driving sensors.
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Redraping is an increasingly common epicanthoplasty method. However, hooding usually remains at the medial part of the upper eyelid. The authors innovated a modification of redraping epicanthoplasty using excision, resulting in a boomerang-shaped defect that does not lead to hooding of the medial upper eyelid.Medial line (M-line) was drawn at the most medial point of the palpebral fissure. The canthus point (C-point) was marked approximately 1 to 3âmm laterally from the M-point, depending on the amount of widening needed. From the C-point, upper incision was designed to meet the double eyelid line. A V-shaped lower incision was designed 3 to 4âmm below the ciliary margin. A flap was elevated about 7âmm superiorly, 10âmm medially, and 5âmm inferiorly. The elevated skin flap was redraped and the M'-point, which reflected the M-point on the redraped skin, was marked. A curvilinear incision line reflecting previous incision lines was drawn. The crescent-shaped excess skin was excised and the medial canthus was retracted medially, and then the boomerang-shaped defect was observed. The M-point and M'-point were coapted with a suture. The dog-ear at the lower side was trimmed.The 525 patients were followed up for ≥3 months postoperatively. The average increase in the palpebral fissure length was 1.2â±â0.5âmm. The average decrease in the interepicanthal distance was 2.4â±â0.9âmm. The average satisfaction score was 4.6â±â0.6.Boomerang epicanthoplasty can prevent hooding on the medial aspect of the upper eyelid. It is easy to design, requires marking only 1 point, and is tension-free, thereby reducing scar widening.
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Blefaroplastia/métodos , Pálpebras/cirurgia , Transplante de Pele/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Feminino , Humanos , Masculino , Margens de Excisão , Satisfação do Paciente , Resultado do Tratamento , Adulto JovemRESUMO
Chronic recurrent multifocal osteomyelitis (CRMO) is a rare autoimmune disease that typically develops during adolescence and primarily affects women. CRMO primarily targets the bone in arms and legs, with sporadic occurrences in the mandible. CRMO is typically managed with medical treatment, and the efficacy of surgery remains controversial. Complications of surgery include massive bleeding and potential flare-up of CRMO symptoms. Herein, we report a patient with CRMO who had lesions in the bilateral rami of the mandible treated with aesthetic mandibular angloplasty. This is the first case of aesthetic mandibular angloplasty in a patient with CRMO who had bilateral rami involvement of the mandible. The patient began experiencing jaw pain accompanied by swelling and throbbing discomfort beneath the jawline at the age of 10. A pediatrician diagnosed CRMO, and the symptoms were controlled with nonsteroidal antiinflammatory drugs and immunosuppressants (infliximab, adalimumab). Aesthetic mandibular angloplasty was performed at our center because of mandibular hypertrophy. This procedure necessitated considerable removal of the spongy bone, raising concerns about potential massive intraoperative bleeding. Approximately 1.5 cm of the mandibular body was excised to reveal the cortical bone. Bleeding during surgery was not severe, rendering blood transfusions unnecessary. The patient was satisfied with the surgical results. This case indicates the feasibility of angloplasty for such cases.
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Background: Overdevelopment of zygomatic bones often results in protrusion and flaring of the midfacial region. This makes the face appear squarer than the more favorable oval shape. Therefore, zygoma reduction surgery has become a commonly performed procedure in patients seeking to obtain an ideal facial shape. Facial soft-tissue ptosis is one of the main complications of zygoma reduction surgery. Previously, the evaluation of cheek soft-tissue ptosis was subjectively based on patients and surgeons. Our study aimed to provide an objective evaluation of soft-tissue sagging in the cheek region after zygoma reduction surgery using artificial intelligence (AI). Methods: We used AI to evaluate cheek sagging in a series of patients who underwent zygoma reduction surgery. We used four methods: tracking facial landmarks, detecting changes in the cheek curvature, and examining changes in the nasolabial fold and marionette lines. Then, the obtained numerical results were assessed for statistically significant differences using statistical validation methods. Results: Use of AI with the four methods demonstrated no statistically significant differences between the pre- and postsurgery evaluations. AI analysis demonstrated that soft-tissue ptosis did not occur in our series of patients. Conclusions: AI offers objective evaluation for both patients and doctors. Future research could build on this application to examine various influencing factors and develop new tools using machine learning to evaluate and predict the extent of cheek sagging in patients before surgery.
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Polyvinylidene fluoride (PVDF) dual-layer hollow fiber membranes were simultaneously fabricated by thermally induced phase separation (TIPS) and non-solvent induced phase separation (NIPS) methods using a triple orifice spinneret (TOS) for water treatment application. The support layer was prepared from a TIPS dope solution, which was composed of PVDF, gamma-butyrolactone (GBL), and N-methyl-2-pyrrolidone (NMP). The coating layer was prepared from a NIPS dope solution, which was composed of PVDF, N,N-dimethylacetamide (DMAc), and polyvinylpyrrolidone (PVP). In order to improve the mechanical strength of the dual-layer hollow fiber, a nucleating agent, sodium 2,2'-methylene bis-(4,6-di-tert-butylphenyl) phosphate (NA11), was added to the TIPS dope solution. The performance of the membrane was evaluated by surface and cross-sectional morphology, water flux, mechanical strength, and thermal property. Our results demonstrate that NA11 improved the mechanical strength of the PVDF dual-layer hollow fiber membranes by up to 42%. In addition, the thickness of the coating layer affected the porosity of the membrane and mechanical performance to have high durability in enduring harsh processing conditions.
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This study analyzed spectral variations of the particulate matter (PM hereafter)-exposed pine trees using a spectrometer and a hyperspectral imager to derive the most effective spectral indices to detect the pine needle exposure to PM emission. We found that the spectral variation in the near-infrared (NIR hereafter) bands systemically coincided with the variations in PM concentration, showing larger variations for the diesel group whereas larger dust particles showed spectral variations in both visible and NIR bands. It is because the PM adsorption on needles is the main source of NIR band variation, and the combination of visible and NIR spectra can detect PM absorption. Fourteen bands were selected to classify PM-exposed pine trees with an accuracy of 82% and a kappa coefficient of 0.61. Given that this index employed both visible and NIR bands, it would be able to detect PM adsorption. The findings can be transferred to real-world applications for monitoring air pollution in an urban area.
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Poluentes Atmosféricos , Pinus , Material Particulado/análise , Poluentes Atmosféricos/análise , Imageamento Hiperespectral , Monitoramento Ambiental/métodos , Emissões de Veículos/análise , Árvores , Folhas de Planta/químicaRESUMO
In photocatalysis, metal-semiconductor hybrid structures have been proposed for ideal photocatalytic systems. In this study, we investigate the effect of morphology and surface nature of Pt cocatalysts on photocatalytic hydrogen evolution activity in Pt-tipped CdSe nanorods. Three distinct morphologies of Pt cocatalysts were synthesized and employed as visible light photocatalysts. The rough tips exhibit the highest activity, followed by the round and cubic tips. Kinetic investigations using transient absorption spectroscopy reveal that the cubic tips exhibit lower charge-separated states feasible for reacting with water and water reduction rates due to their defectless surface facets. In contrast, the rough tips show a similar charge-separation value but a two-fold higher surface reaction rate than the round tips, resulting in a significant enhancement of hydrogen evolution. These findings highlight the importance of rational design on metal cocatalysts in addition to the main semiconductor bodies for maximizing photocatalytic activities.
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The purpose of this study is to investigate the effect of forest conservation activities on the physical and psychological wellbeing of participants. The experiment was conducted in a forest near an urban area and involved 61 participants (average age: 22.5 ± 1.8). The participants selected one of three activities (pruning, stacking cut branches, and removing vines) in the forest conservation program. The effects of these activities on the musculoskeletal system were assessed using the Ovako Working Posture Assessment System (OWAS); the physical intensity of the activities was evaluated using heart rate data. The psychological evaluation measurement indexes used the Positive and Negative Affect Schedule, Rosenberg Self-Esteem scale, World Health Organization Quality of Life assessment instrument, and the Perceived Restorativeness Scale. As a result of the OWAS assessment, forest conservation activities were found to be action categories 1 and 2, which were less burdensome to the musculoskeletal system. All forestry activities were found to be light levels of physical intensity. Psychological evaluation of the participants revealed that positive emotions such as self-esteem, quality of life, and perceived restorativeness increased significantly, whereas negative emotions decreased significantly. This forest conservation program, that involved low-intensity activities which were less burdensome to the musculoskeletal system, had positive physical and psychological effects on the local residents who participated.
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Saúde Mental , Qualidade de Vida , Adulto , Participação da Comunidade , Conservação dos Recursos Naturais , Florestas , Humanos , Adulto JovemRESUMO
Even though the COVID-19 pandemic has discouraged travel and people's movements, the number of visitors to forests near cities which are easily accessible by private vehicle is increasing in Korea. This study aims to investigate the relationship between stress, perceived restorativeness, forest recreation motivation, and the mental well-being of forest users. A survey of forest users was conducted at three recreational forests near Seoul in the summer of 2020. A total of 1196 forest users (613 males and 583 females) participated in the study. As a result of the data analysis, it was found that stress had a negative correlation with perceived restorativeness, forest recreation motivation, and mental well-being; perceived restorativeness had a positive correlation with mental well-being, and forest recreation motivation had a positive correlation with mental well-being. For the relationship between stress and mental well-being, the fitness index that was mediated by the perceived restorativeness and the forest recreation motivation found that the model was statistically suitable. Through this study, a research model was derived that, if the stress of forest users is reduced, direct or indirect effects on perceived restorativeness, forest recreation motivation, and mental well-being are increased. Further, a multi-group analysis found that the effect of perceived restorativeness and forest recreation motivation on the mental well-being of the male group was higher than the effect on the female group. Using this research model to find ways to promote health in forests can be utilized for forest management or forest healing.
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COVID-19 , COVID-19/epidemiologia , Feminino , Florestas , Promoção da Saúde , Humanos , Masculino , Motivação , Pandemias , RecreaçãoRESUMO
OBJECTIVES: Women experience more stress in middle age than in other periods of their lives. Therefore, health management programs that enable middle-aged women to cope with and manage stress are needed. This study investigated the psychological effects of a meditation-focused forest therapy program among 53 middle-aged women living in urban areas in Korea. METHODS: Participants were divided into 2 groups: one group underwent the program for 3 days in a forest, followed by 3 days in an urban environment, and the other group underwent the program for 3 days in the urban environment, followed by 3 days in the forest. The psychological effects of the forest therapy program were evaluated using the Profile of Mood States-Brief (POMS-B). Differences in mood state before and after the program conducted in the forest (experimental group) and in the urban environment (control group) were evaluated using the paired-samples t-test. RESULTS: The program in the forest significantly reduced tension, depression, anger, fatigue, and confusion among the domains of the POMS-B. The program in the urban area significantly reduced tension, but not depression, anger, fatigue, or confusion. CONCLUSIONS: Meditation-focused forest therapy programs are expected to contribute to promoting psychological health and enhancing the quality of life of middle-aged women.
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Florestas , Qualidade de Vida , Fadiga , Feminino , Humanos , Saúde Mental , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , República da Coreia , Estresse Psicológico/terapiaRESUMO
OBJECTIVES: To clarify the relaxing effects of a 5-min stay in a hospital's rooftop forest on elderly patients requiring care. METHODS: This was a within-subject, cross-sectional study. The participants were 30 elderly female patients requiring help in walking, aged 81.2±6.4 (mean±SD). A simplified emotional 7-point rating scale from -3 to 3 for 5 pairs of emotions, which was derived from the two-question Whooley Depression Screen, was used as a subjective indicator. The experimental areas were the rooftop forest that covered an area of 122 m(2) on the rooftop of a four-story health service facility and an outdoor car park area (as the control area). The participants were instructed to sit still in a wheelchair and view the scenery for 5 min in each experimental area and were then assessed. Data from the participants during exposure to the rooftop forest were compared with those during exposure to the control area. First, 15 participants moved to the rooftop forest from the preroom, and the other 15 moved to the outdoor car park area, and then they moved to the other site to eliminate any order effect. RESULTS: In the rooftop forest, the mean scores of the simplified emotional rating were 1.70 (1.17 for control) for "hopeful", 1.70 (1.17) for "interest in doing things", 1.53 (1.10) for "enjoyment", 1.67 (1.17) for "calm", and 2.03 (1.30) for "secure". The scores were all significantly higher than those in the control (p<0.01). CONCLUSION: It was demonstrated that a visit to the rooftop forest induced a significant subjective relaxing effect in elderly female patients requiring care.
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Relaxamento/fisiologia , Árvores , Idoso de 80 Anos ou mais , Pessoas com Deficiência , Emoções , Feminino , Hospitais , HumanosRESUMO
Five million years has passed since a subset of primates recognizably became human. Because we have already spent more than 99.99% of our evolutionary history in natural environments, it is thought that we are essentially adaptive to nature. However, we live in a society characterized by urbanization and artificiality, despite our physiological functions still being adapted to nature. We conducted experiments involving 420 subjects at 35 different forests throughout Japan. As a result, these subjects sitting in natural surroundings showed decreases in the following physiological indices compared with the urban control group: 12.4% decrease in cortisol level, 7.0% decrease in sympathetic nervous activity, 1.4% decrease in systolic blood pressure, and 5.8% decrease in heart rate. This shows that stressful states can be relieved by forest therapy. It should also be noted that parasympathetic nerve activity increased by 55.0%, indicating a relaxed state. The results of walking experiments were also similar. Li et al. demonstrated that immune functions are enhanced by forest therapy. Middle-aged employees volunteered to participate in these experiments. NK (natural killer cells) activity, as an indicator of immune function, increased by 56% on the second day and returned to normal levels. A significant increase of 23% was maintained for 1 month even after these subjects returned to urban life, clearly illustrating the preventive medical effects of nature therapy. We expect nature therapy to play an increasingly important role in preventive medicine in the future.
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Estresse Psicológico/prevenção & controle , Árvores , Humanos , Pessoa de Meia-Idade , Relaxamento/fisiologiaRESUMO
OBJECTIVE: To provide scientific evidence of the health benefits of forest therapy in terms of physiological indices. DESIGN: Within-group comparison made by conducting field experiments. PARTICIPANTS: Forty-eight young male adults. METHODS: Field experiments were conducted at four local sites in Japan. At each site, 12 adults participated in a three-day experiment. To compare physiological reactions between two environmental stimuli, experiments were conducted in forest and urban environments. The participants were randomly assigned to visit either the forest or an urban setting and were instructed to view the landscape in a seated position. The physiological reactions of each participant were recorded before, during, and after viewing the stimuli, and the differences in physiological indices were compared between the two groups. RESULTS: Physiological data revealed that participants demonstrated significantly different reactions in the forest and urban environments. Analysis of heart rate revealed that participants showed a significantly higher ln(HF) and a lower ln(LF/HF) in the forest environment than in the urban environment. Systolic and diastolic blood pressures, pulse rate, and salivary cortisol concentration significantly decreased in the forest environment compared with the urban environment. Subjective evaluation data were generally in accordance with physiological reactions, showing significantly higher scores for "comfortable, natural, soothed, and refreshed feelings" in the forest environment than in the urban environment. CONCLUSIONS: This study provided very clear scientific evidence of the physiological effects of forest therapy. Our data indicate that forest therapy can decrease stress and facilitate physiological relaxation.
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Relaxamento/fisiologia , Árvores , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/análise , Masculino , Pulso Arterial , Saliva/química , Adulto JovemRESUMO
OBJECTIVES: In the present study, we aimed to clarify the psychological effects of shinrin-yoku (taking in the atmosphere of the forest) by conducting field experiments. METHODS: The experiments were conducted in 19 forested and urban areas in Japan during the 2007-2010 period. Twelve male students participated at each of the 19 areas (a total of 228 persons). Subjective ratings of "comfortable-uncomfortable", "soothing-stimulating", and "natural-artificial" feelings were conducted after each of the participants had viewed the scenery for 15 min in the forested and urban areas. A postviewing questionnaire on "stressed-refreshed" feelings was also administered and the Profile of Mood State (POMS) questionnaire was employed to assess six aspects of mood before and after viewing the sceneries. RESULTS: The forest environments were perceived as significantly more "comfortable", "soothing", and "natural" than the urban environments after viewing the sceneries. The score for "refreshed feeling" was also significantly higher in the forested areas. The score for the "vigor" subscale of POMS was significantly higher after viewing the scenery in the forested areas, whereas the scores for negative feelings such as "tension-anxiety", "depression-dejection", "anger-hostility", "fatigue", and "confusion" significantly decreased. CONCLUSION: Collectively, these results suggest that the forest environments have significant beneficial and relaxing effects on human's moods compared with the urban environments.