Subjective Discomfort Levels Research Articles

Discomfort in pedestrian-electric scooter interactions during frontal approaches

BackgroundAs urban landscapes rapidly integrate e-scooters into their transportation ecosystems, understanding pedestrian-e-scooter interactions becomes paramount for safety and planning. This study investigates pedestrian discomfort levels and avoidance strategies when encountering an e-scooter approaching from the front. Methods25 participants were exposed to e-scooters approaching at three different speeds and lateral distances. Avoidance paths were plotted, and subjective discomfort levels were recorded and analysed. ResultsOur findings underscored two key behaviours: 1) As the speed of the e-scooter increased, participants initiated avoidance manoeuvres from a further distance ahead, suggesting a heightened perception of risk. 2) Regardless of the e-scooter's speed, the lateral distance maintained during passing remained fairly constant. However, when the e-scooter's initial lateral position was closer to participants, both the initiation distance for avoidance and the reported discomfort level increased noticeably. ConclusionThe findings underscore the critical influence of lateral distance and e-scooter speed on pedestrian comfort and avoidance behaviour. These insights can guide urban planners and policymakers in designing safer and more efficient shared spaces.

Investigation of the Effect of Emotional Freedom Technique on Stress and Anxiety in Nursing Students in the Covid-19 Pandemic

COVID19 pandemic has caused nursing students studying in the clinical field to stay away from the clinic for a long time due to the interruption of education. This process affected the anxiety levels of nursing students, causing them to feel inadequate and experience stress. This study aims to investigate the effect of the emotional freedom technique on nursing students' styles of coping with anxiety and stress. In the experimentally designed study with a pretest-posttest control group, the emotional freedom technique was applied to the experimental group in 4 sessions. In addition, the state anxiety scale, coping styles scale, subjective discomfort level scale was applied during the pre-application phase and after the emotional freedom technique session. As a result, it was determined that the students in the experimental group had higher mean scores of coping with stress inventory, seeking social support, optimism, self-confidence, and submissive approach measurement scores in the post-test, and state anxiety scale measurement scores measured in the post-test. Therefore, alternative approaches such as the emotional freedom technique that nursing students can apply to reduce their anxiety levels and increase their coping with stress should be encouraged.

Ergonomic Improvements to Agricultural Harvest Baskets to Reduce the Risk of Musculoskeletal Disorders among Farmers.

Typical harvesting baskets (TB) are used in various agricultural workplaces; however, no study to date has reported their effect on the musculoskeletal system. Therefore, this study aimed to evaluate the effects of a novel basket with attached rotational handles (RHB) to help alleviate the work-related physical burden of farmers. We analyzed the surface electromyograms (EMGs) of seven muscles, evaluated the subjective discomfort levels and locally perceived discomfort (LPD) scores to investigate the discomfort in the whole body and seven hand muscles, respectively. The EMGs showed that muscle activity decreased in five muscles (flexor carpi ulnaris, extensor carpi radialis, lateral triceps, middle deltoid, and upper trapezius) and increased in two (biceps brachii and erector spinae) when the RHB was used (p < 0.05). The subjective discomfort score for the RHB decreased compared to that for TB (p < 0.001). The LPD scores also decreased, and the RHB and TB scores ranged from 1.25–1.40 and 3.1–3.25, respectively. The use of the RHB may prevent wrist bending, and reduce the activity of certain muscles while increasing the activity of other muscles. Therefore, it is necessary to conduct training and to evaluate the working posture while considering the affected muscles.

An Investigation of the Implications of Visual Impairment for Illumination Requirements

Introduction The present contribution mainly focuses on the evaluation of the visual performance of people with impaired vision and, for comparison purposes, individuals with typical vision under different lighting conditions. Methods: A monitor with adjustable brightness facilitated various test runs to determine the visual performance as a function of the adaptation luminance and glare. In addition, the subjective impressions of the participants with impaired vision were queried via interviews. The study included 98 people with impaired vision and 38 people without visual impairments. Results: The interview results suggest that most people with visual impairments require special lighting conditions. An increased lighting requirement is observed amongst 50% of this group. Moreover, 75% of this group display increased glare sensitivity. Likewise, adaptation problems and critical issues related to nonuniform lighting are manifest. Individuals with impaired vision included in this study display a greatly reduced contrast threshold and a higher subjective level of discomfort compared to individuals with typical vision.Discussion: Most visually impaired participants state that they require a higher degree of brightness to achieve their maximum personal visual performance. However, about a quarter of the participants reported that they achieve a better visual performance at lower brightness, while displaying an increased sensitivity to glare. In general, glare has a decisive influence on the visual performance of the participants with impaired vision in our study. Implications for Practitioners: The study reconfirms the essential importance of glare-free and uniform general lighting strategies (e.g., via predominantly indirect lighting) as well as avoiding abrupt spatiotemporal luminance changes (e.g., via provision of a transition zone between locations with very different luminance levels).

Bi-disparity sparse feature learning for 3D visual discomfort prediction

Viewing stereoscopic images sometimes causes viewers to feel inconvenience, which is called 3D visual discomfort. Excessive horizontal disparity, misalignment between the left and right views, or depth cues conflicts are some of the important factors involved in 3D visual discomfort. The ability to estimate the degree of 3D visual discomfort can be used to improve the 3D display systems and provide acceptable binocular visual quality. Most of the existing visual discomfort prediction (VDP) approaches extract hand-crafted features based on perceptual modeling and statistical analysis of disparities. We have proposed a simple yet effective VDP model based on unsupervised learning of sparse features which are highly predictive of subjective discomfort levels. These features are extracted from the aggregation of left and right disparity maps. This aggregation effectively highlights the areas with sudden changes and high levels of disparities where discomfort is most likely to occur. The regression model trained by the features, predicts high correlated 3D visual discomfort scores on each dataset. The cross-database results are also superior to other reported ones.

ROLE OF RESPIRATORY RATE IN THE TOLERABILITY OF PERSONAL RESPIRATORY PROTECTION EQUIPMENT

The factor limiting the tolerance of personal respiratory protection equipment should be considered the frequency of respiratory movements, which reflexively changes when additional respiratory resistance occurs. Unfortunately, there is almost no information in the available literature about changes in the tolerability of personal respiratory protection equipment at different rates of respiratory movements. The purpose of this work was to study the tolerability of personal respiratory protection equipment when changing the frequency of respiratory movements.The study was conducted on practically healthy persons of both sexes (78 people), aged from 20 to 36 years. To simulate the conditions for the use of personal respiratory protection equipment, inspiratory resistive respiratory loads of 20% of the maximum intraoral pressure during the Mueller test were used. The tolerance of personal respiratory protection equipment was assessed using the Borg visual analogue of dyspnea scale, which reflected the level of subjective discomfort that occurs when additional respiratory resistance is turned on. During the action of additional respiratory resistance, the persons were asked to hold the frequency of respiratory movements, which was set using a special setting.An increase in the rate of respiratory movements against the background of additional respiratory resistance leads to a significant deterioration in the objective and subjective indicators of the functional state of the persons; replacing the inhaled air with an oxygen-rich respiratory mixture with carbon dioxide absorption did not lead to a significant improvement in the functional state. A moderate decrease (up to 70% of the initial frequency of respiratory movements) in the rate of respiration leads to an improvement in the indicators of adaptive activity in conditions of additional respiratory resistance. A significant decrease (up to 35% of the initial frequency of respiratory movements) in the rate of respiration under conditions of additional respiratory resistance leads to a deterioration of objective and subjective indicators of the functional state of the subjects.An increase in peak respiratory flow rates caused by an increase in the rate of respiration, in accordance with the well – known Rohrer equation, significantly increases inelastic resistance and, as a result, respiratory needs. These needs can be met at some time due to a significant increase in the work of the respiratory muscles, but due to fatigue of the latter, psychoemotional tension increases quite quickly and the use of personal respiratory protection equipment is abandoned.

GAS COMPOSITION OF ALVEOLAR AIR AND TOLERABILITY OF PERSONAL RESPIRATORY PROTECTION EQUIPMENT

Introduction. When using personal protective equipment for respiratory organs of an insulating type in case of depletion of a regenerative cartridge, hypoxic-hypercapnic changes in the gas composition of the body occur, which have a negative effect on the tolerance of personal protective equipment for respiratory organs. The combination of additional respiratory resistance with hypoxia and hypercapnia further worsens the tolerance of respiratory protective equipment. The purpose of this study was to study the tolerance of personal respiratory protection when changing the gas composition of the alveolar air. Material and methods. The study was conducted on healthy subjects of both sexes (78 people), aged 20 to 36 years. To simulate the conditions for the use of personal respiratory protective equipment, inspiratory resistive respiratory loads of 20% of the maximum intraoral pressure were used during the Mueller test. The tolerance of respiratory protective equipment was evaluated using the Borg visual analog scale of dyspnea, which reflected the level of subjective discomfort occurring due to additional respiratory resistance is turned on. The methodology for changing the gas composition of the alveolar air in the subjects consisted of using a system that allowed adding oxygen from the line to the closed spirograph circuit and turning the carbon dioxide adsorber on and off. Results. The tolerance of personal respiratory protection is associated with the nature of the gas composition of the alveolar air. A minimum of subjective discomfort was observed in the presence of hyperoxic-hypocapnic composition of the pulmonary air; on the contrary, an increase in subjective discomfort on the Borg scale was observed with a reduced oxygen content and an increased concentration of carbon dioxide. The use of personal respiratory protective equipment against the background of hypoxia-hypercapnia negatively changes the functional state of the body: there was observed an increase in physiological expenditures by leading effectors. Normalization of the gas composition of the body under the use of personal respiratory protection did not lead to complete optimization of the functional state of the subjects. Conclusion. Hypoxia and hypercapnia arising from the depletion of regenerative cartridges of the respiratory protective equipment of an insulating type leads to a significant deterioration in the tolerance to additional respiratory resistance. The alleged mechanism of this phenomenon should be considered as an increase in fatigue of the respiratory muscles.

An Investigation of the Side Effects, Patient Feedback, and Physiological Changes Associated with Direct-Acting Antiviral Therapy for Hepatitis C.

Background: Hepatitis C virus (HCV) infection is one of the major causes of liver cirrhosis and hepatocellular carcinoma globally. The advent of direct-acting antivirals (DAAs) with high cure rates provides an opportunity to reduce the rising HCV disease burden. However, few studies have explored the side effects and physiological benefits of DAA therapy in rural areas. The aim of this study was to investigate the subjective reports of discomfort, patient feedback about the course of treatment, and physiological changes after DAA treatment in HCV patients. Methods: A descriptive, prospective, comparative cohort study was conducted from January to August 2019 in western coastal Yunlin County, Taiwan. Data regarding demographic characteristics, subjective discomfort levels, and physiological responses were collected through face to face interviews and from medical records by a cooperating hospital. Results: Six-hundred-and-twenty-three participants with an active HCV infection were identified; 555 (89.1%) had completed treatment, and sustained virologic response was achieved in 99.6% (n = 553). The mean age was 64.9 (standard deviation = 13.1) years, and 35% of patients experienced discomfort during DAA treatment, including fatigue, itching, and dizziness. After three months of treatment, physiological markers, including body weight (p < 0.001), waist circumference (p < 0.05), blood pressure (p < 0.001), alanine aminotransferase (p < 0.001), and aspartate aminotransferase (p < 0.001), had significantly improved. Almost all participants provided positive feedback about the treatment experience and reported manageable side effects. Conclusions: The findings showed that, in an endemic rural area, DAA treatment had a high cure rate and improved physiological markers with few discomforts. These results can be used to reduce the barriers HCV patients face in adopting new medications.

The clinical study of modified transseptal suturing after septoplasty

Objective:To study whether modified transseptal suturing could be an alternative to packing after septoplasty. Method:We conducted a prospective randomized controlled trial. The study involved 40 patients who underwent septoplasty. Patients were randomly divided into two groups, one with anterior nasal packing and the other with modified transseptal suturing. Patients were asked to record their subjective discomfort levels on a visual analogue scale（VAS） during 48 h postoperatively. Both groups were compared for VAS, postoperative complications 2 weeks after septoplasty through nasal endoscope, the datum of rhinomanometry before surgery and 2 weeks after surgery. Result:The differences of mean postoperative VAS score between two groups were statistically significant（P<0.05）. The patients of nasal packing group experienced more discomforts than the other group. No statistically significant between two groups in terms of the datum of rhinomanometry before surgery and 2 weeks after surgery（P>0.05）. There were no bleeding, septal hematoma, nasal septum perforation and local infection in all patients 2 weeks after septoplasty. During follow-up 1 case was found with postoperative nasal adhesion, nasal vestibular swelling and fester were seen in two patients and nasal peculiar smell was found in 1 case in nasal packing group. We can find that there were a lot of blood crust in silicone ventilation tube about in 14 patients in packing group. However, the suturing group could see none of the above questions. Conclusion:Modified transseptal suturing is more simple and convenient than nasal packing. In a word, the use of modified transseptal suturing could be an alternative topacking after septoplasty.

A clinical screening tool for objective and subjective cognitive disorders in multiple sclerosis.

Cognitive dysfunction is common in multiple sclerosis (MS). Deficits can affect attention, concentration, planning, and memory. They can have severe functional consequences in many domains. Cognitive complaints are frequently associated with other confounding factors (fatigue, anxiety, depression, or treatment side effects). In most cases, cognitive assessment is proposed after a spontaneous complaint, but determining the extent of discomfort perceived by the patient, the influence of coexisting factors, or the optimal timing for a more complete neuropsychological assessment is difficult. The objective of this work was to evaluate the feasibility and relevance of a fast global assessment of both objective and subjective cognitive dysfunction in MS. MS patients underwent a brief cognitive assessment including 7 visual analogue scales (VASs) asking about the patient's subjective level of discomfort in various domains, a memory test (Barbizet's lion story), a commonly used test of information processing speed (Symbol Digit Modalities Test [SDMT]) and self-reporting questionnaires for fatigue and mood (Fatigue Severity Scale [FSS] and Hospital Anxiety and Depression Scale [HADS]). Spearman correlation coefficients among scores were estimated. The mean age of the 73 patients included was 48.3 (SD 11.1) years; 78% were females and 52.8% had the remittent-recurrent MS form, 8.3% the primary progressive form, and 38.9% the secondary progressive form. In less than 20min, this brief cognitive assessment was able to identify symptoms and quantify discomfort level. Symptoms of fatigue and anxiety frequently coexisted with cognitive complaints. We found modest correlations between scores on the VAS fatigue and the FSS and between scores on the VAS mood and the HADS. Analytical evaluation revealed that most patients had similar SDMT and recall profiles; however, a small proportion showed a dissociation between these 2 tests, which validated the inclusion of both tests in the assessment. Accounting for coexisting factors (e.g., anxiety and fatigue) and their functional repercussions is essential for prioritizing these problems within the context of multidisciplinary patient treatment. Considering the possible multifactorial character of cognitive dysfunction in MS, it is essential to ask patients about their experiences and to take into account cognitive complaints in the follow-up of patients. The assessment tool we propose is simple and easy to use in a clinical setting and provides the information necessary for requesting (or not) a more complete neuropsychological assessment.

Visual Impairment, Adaptation Luminance, and Glare: An Empirical Investigation

Visually impaired people primarily rely on their remaining vision. Unfavorable lighting conditions can further hamper this remaining vision. In this context, the present contribution mainly focuses on the evaluation of the visual performance of visually impaired and normally sighted individuals under different lighting conditions. To investigate the visual performance empirically, we developed a test involving different adaptation luminance values. A monitor with adjustable brightness facilitated various tests to determine the visual performance as a function of the adaptation luminance and glare. In addition, the subjective impressions of the visually impaired participants were captured via interviews. The study included 98 visually impaired people and 38 people without eye-related ailments. The interview results suggest that most people with visual disabilities require special lighting conditions. An increased lighting requirement is observed amongst 50% of this group. Moreover, 75% of this group display increased glare sensitivity. Likewise, adaptation problems and critical issues related to non-uniform lighting are manifest. Visually impaired individuals display significant in the visual performance variance at different brightness levels. Individuals with eye disease display a greatly reduced contrast threshold and a higher subjective level of discomfort compared to individuals with normal vision. Most visually impaired individuals require a higher degree of brightness to achieve their maximum personal visual performance. About a quarter of these individuals achieves the optimal visual performance at lower brightness, while displaying an increased sensitivity to glare. In general, glare has a decisive influence on the visual performance of visually impaired people. For general lighting purposes, a predominantly indirect lighting source better accommodates these individuals' requirements.

Effectiveness and Safety of Cataract Surgery Pharmacological Support in Glaucoma Patients

Purpose:To evaluate effectiveness and safety of cataract surgery pharmacological support (which include 0.5 % levofloxacin, 0.09 % bromfenac and preservative free polyvinylpyrrolidone and polyvinyl alcohol fixed combination instillations) in glaucoma patients.Patients and Methods:Standard ophthalmological examination, subjective discomfort level evaluation, tear film break up time, tear meniscus height measurement, index of xerosis, evaluation and ocular surface condition photoregistration were performed in 40 II «A» primary open-angle glaucoma patients, receiving hypotensive therapy, before and after phacoemulsification (Ph). All patients in the postoperative period received instillations: 0.5 % levofloxacin (4 times a day, 7 days), 0.1 % dexamethasone (3 times a day, 7 days), 0.09 % bromfenac (once a day, 30 days) and preservative free polyvinylpyrrolidone and polyvinyl alcohol fixed combination (3 times a day, 30 days). Control points were: examination before Ph, on 1, 7 and 30 days after Ph. Results: None cases of infectious or inflammatory surgery complications were recorded. The SD level was significantly increased on the 1 and 7 days after Ph, by the 30 day the SD level was significantly decreased, compared with a state on the 1 and 7 days. On the 1, 7, 30 days after Ph TFBUT significantly decreased. By the 30 day after Ph the TFBUT was significantly increased in compare with 1 and 7 days after operation. TMH changes after Ph had multidirectional character and in general were not significant throughout the observation, with a tendency to increase on the 1 and 30 days after surgery and to decrease on the 7th day. IX dynamics in compare with a state before Ph was not significant in all control points with a tendency to its increase on the 1 and 7 days after operation and to decrease on the 30th day. In general, pharmacological support of Ph was assessed by all patients as comfortable, there was no intolerance.Conclusion:The cataract surgery pharmacological support in glaucoma patients (including 0.5 % levofloxacin, 0.09 % bromfenac and preservative free polyvinylpyrrolidone and polyvinyl alcohol fixed combination instillations) showed: high efficiency (in prevention of infectious and inflammatory complications); safety by influence on the ocular surface; comfort of use.

Discomfort Evaluation of Truck Ingress/Egress Motions Based on Biomechanical Analysis.

This paper presents a quantitative discomfort evaluation method based on biomechanical analysis results for human body movement, as well as its application to an assessment of the discomfort for truck ingress and egress. In this study, the motions of a human subject entering and exiting truck cabins with different types, numbers, and heights of footsteps were first measured using an optical motion capture system and load sensors. Next, the maximum voluntary contraction (MVC) ratios of the muscles were calculated through a biomechanical analysis of the musculoskeletal human model for the captured motion. Finally, the objective discomfort was evaluated using the proposed discomfort model based on the MVC ratios. To validate this new discomfort assessment method, human subject experiments were performed to investigate the subjective discomfort levels through a questionnaire for comparison with the objective discomfort levels. The validation results showed that the correlation between the objective and subjective discomforts was significant and could be described by a linear regression model.

Effects of Working Environment Factors and Operator Experience on Upper Extremity Mechanical Properties During Powered Hand Tool Use

OCCUPATIONAL APPLICATIONS Powered hand tools are widely used during assembly operations. The hand displacement during powered hand-tool use has been identified as a potential risk factor for upper extremity musculoskeletal disorders. In the current study, the mechanical properties of the upper extremity were identified, which represent muscle capacity to react to an impulsive power tool torque loading and affect the responsive hand displacement. These properties were obtained from among experienced and inexperienced participants under various operating configurations, including working heights, horizontal working distances, tool moments of inertia, and joint type. The results indicated that operating configurations and experiences affected the mechanical properties of upper extremities in different ways. This research may help in future studies on powered hand-tool work-station design, for example by improving parameters in biomechanical models.TECHNICAL ABSTRACT Rationale: Hand-tool displacement during powered hand-tool use is a potential risk factor for upper extremity injuries and is correlated to the subjective discomfort level. The upper extremity has been modeled as a second-order linear system to describe the hand-tool response. While previous studies have found that working environment factors and operator experience significantly affect the hand-tool response during powered tool use, how those factors affect the mechanical properties of the upper extremity has not been investigated. Purpose: This study assessed the mechanical properties of the upper extremity under various working environment factors and operator experience levels. Method: A least-squares method was used to identify the mechanical properties of the upper extremity during powered hand-tool use, directly from the dynamics of hand-tool response. Results: Working heights, horizontal working distances, hand tool moments of inertia, joint type, and experience significantly affected some mechanical properties of the upper extremities in various operating configurations. In addition, stiffness and damping coefficients of the upper extremities were greater than those values identified from a free oscillation system in a previous study. Conclusions: Mechanical properties of the upper extremities can be used to predict hand displacement during powered hand-tool use. The current results provide additional information to improve the understanding of operator reactions to powered hand tools.

Analysis of physiological responses associated with emotional changes induced by viewing video images of dental treatments.

Since the understanding of emotional changes induced by dental treatments is important for dentists to provide a safe and comfortable dental treatment, we analyzed physiological responses during watching video images of dental treatments to search for the appropriate objective indices reflecting emotional changes. Fifteen healthy young adult subjects voluntarily participated in the present study. Electrocardiogram (ECG), electroencephalogram (EEG) and corrugator muscle electromyogram (EMG) were recorded and changes of them by viewing videos of dental treatments were analyzed. The subjective discomfort level was acquired by Visual Analog Scale method. Analyses of autonomic nervous activities from ECG and four emotional factors (anger/stress, joy/satisfaction, sadness/depression and relaxation) from EEG demonstrated that increases in sympathetic nervous activity reflecting stress increase and decreases in relaxation level were induced by the videos of infiltration anesthesia and cavity excavation, but not intraoral examination. The corrugator muscle activity was increased by all three images regardless of video contents. The subjective discomfort during watching infiltration anesthesia and cavity excavation was higher than intraoral examination, showing that sympathetic activities and relaxation factor of emotion changed in a manner consistent with subjective emotional changes. These results suggest that measurement of autonomic nervous activities estimated from ECG and emotional factors analyzed from EEG is useful for objective evaluation of subjective emotion.

Self-Care Practices for Common Colds by Primary Care Patients: Study Protocol of a European Multicenter Survey-The COCO Study.

Background. Self-care for common colds is frequent, yet little is known about the spectrum, regional differences, and potential risks of self-care practices in patients from various European regions. Methods/Design. We describe the study protocol for a cross-sectional survey in 27 primary care centers from 14 European countries. At all sites, 120 consecutive adult patients, who visit their general practitioner for any reason, filled in a self-administered 27-item questionnaire. This addresses patients' self-care practices for common colds. Separately, the subjective level of discomfort when having a common cold, knowing about the diseases' self-limited nature, and medical and sociodemographic data are requested. Additionally, physicians are surveyed on their use of and recommendations for self-care practices. We are interested in investigating which self-care practices for common colds are used, whether the number of self-care practices used is influenced by knowledge about the self-limited nature of the disease, and the subjective level of discomfort when having a cold and to identify potential adverse interactions with chronic physician-prescribed medications. Further factors that will be considered are, for example, demographic characteristics, chronic conditions, and sources of information for self-care practices. All descriptive and analytical statistics will be performed on the pooled dataset and stratified by country and site. Discussion. To our knowledge, COCO is the first European survey on the use of self-care practices for common colds. The study will provide new insight into patients' and general practitioners' self-care measures for common colds across Europe.

수직형 손잡이와 수평형 손잡이의 높이와 간격에 따른 미는 힘 비교

Manual materials handling tasks are the main risk factors for the work-related musculoskeletal disorders. Many assistant tools for manual materials handling are being used in various kind of industries. One of them is a 4-wheeled cart which is widely used in manufacturing factories, hospitals, etc. The major force required to control the 4-wheeled cart is pushing and pulling. There are two types of handles being used for the 4-wheeled cart : vertical type (two vertical handles), and horizontal type (one horizontal handle). This study tried to investigate the pushing forces and subjective discomforts (hand/writst, shoulder, low back, and overall) of the two handle types with different handle height and distance conditions. Twelve healthy male students (mean age = 23.4 years) participated in the experiment. The independent variables were handle angle (horizontal, vertical), handle height (low, medium, high), and handle distance (narrow, medium, wide). The full factorial design was used for the experiment and the maximum pushing forces were measured in 18 different conditions (2×3×3). Analysis of variance (ANOVA) procedure was conducted to test the effects of the independent variables on the pushing force and discomfort levels. Handle height and angle were found to be the critical design factors that affect the maximal pushing forces and subjective discomfort. In the middle height, subjects exerted higher pushing forces, and experience lower discomfort levels compared to the high, and low height. There was no statistical influence of the handle distance to the pushing forces and subjective discomfort levels. It was found out that the effects of the handle angle (horizontal and vertical) on both pushing force and subjective discomfort were statistically significant (p < 0.05). The vertical handle revealed higher pushing force and lower discomfort level than the horizontal handle. The reason for that was thought to be the different postures of the hand when grasping the handles. The horizontal handle induced pronaton of the hand and made hand posture more deviated from the neutral position. Keyword : Handle design, Handle angle, Handle height, Handle distance, Maximal pushing force †이 논문은 2014년 대구가톨릭대학교 교내 연구지원금에 의한 것임 †Corresponding Author : Young-Woong Song, 13-13 Hayang-ro, Hayang-eup, Gyeongsan-si, Gyeongbuk, Korea 712-702 Received October 20, 2014; Revision Received December 12, 2014; Accepted December 18, 2014. 수직형 손잡이와 수평형 손잡이의 높이와 간격에 따른 미는 힘 비교 송 영 웅 372

Use of high-frequency visual stimuli above the critical flicker frequency in a SSVEP-based BMI

ObjectiveThis study presents a new steady-state visual evoked potential (SSVEP)-based brain–machine interface (BMI) using flickering visual stimuli at frequencies greater than the critical flicker frequency (CFF). MethodsWe first asked participants to fixate on a green/blue flicker (30–70Hz), and SSVEP amplitude was evaluated. Participants were asked to indicate whether the stimulus was visibly flickering and to report their subjective level of discomfort. We then assessed visibly (41, 43, and 45Hz) vs. invisibly (61, 63, and 65Hz) flickering stimulus in an SSVEP-based BMI. Visual fatigue was assessed via the flicker test before and after operation of the BMI. ResultsHigher frequency stimuli reduced participants’ subjective discomfort. Participants successfully controlled the SSVEP-based BMI using both the visibly and invisibly flickering stimuli (93.1% and 88.0%, respectively); the flicker test revealed a decrease in CFF (i.e., visual fatigue) under the visible condition only (–5.7%, P<0.001). ConclusionsThe use of high-frequency visual stimuli above the CFF led to high classification accuracy and decreased visual fatigue in an SSVEP-based BMI. SignificanceHigh-frequency flicker stimuli above the CFF were able to induce SSVEPs and may prove useful in the development of BMI-based assistive products.

Visually transforming artwork and guided imagery as a way to reduce work related stress: A quantitative pilot study

This paper explores ways of transforming stress related visual images for health care professionals who are exposed to stressful images in their work. Transformation of these images is conducted using changes of compositional elements such as shape, color, size and texture – through harnessing the power of creativity and imagination to transform an image that is drawn or imagined. We hypothesize that subjective discomfort levels (SUDS) will be reduced by visually transforming their images. We also assume that similar elements of color, size shape and texture will be drawn and imagined. Thirty-six health professionals participated in a five hours workshop that took place in two consecutive days. SUDS levels were calculated and were found to be reduced following image transformation in both art and imagery. On a comparative level, the elements of ‘shape ‘size’ and ‘color’, were highly used in both techniques and did not differ statistically significantly.The compositional elements used to transform images are discussed as a theoretical base for reducing work related stress.

Effect of a Single Pulsed Shortwave Diathermy Treatment on Extensibility of the Hamstrings

Context:Lack of extensibility of the hamstrings is manifested by a restricion of knee extension range of motion.Objective:To quantify the effect of a single pulsed shortwave diathermy treatment on extensibility of the hamstrings.Participants:Twenty volunteers with tight hamstrings (&lt; 150° of active knee extension).Intervention:Subjects were randomly allocated to receive either a pulsed shortwave diathermy treatment (experimental group) or a simulated pulsed shortwave diathermy treatment that did not produce a deep tissue heating effect.Main Outcome Measurements:Measurements of active and passive range of movement were recorded before and after the treatment, as well as the subjective level of discomfort perceived during the passive stretching.Results:No statistically signifcant differences were found.Conclusion:A single pulsed shortwave diathermy treatment, without stretching, did not increase hamstring extensibility.