Optimal Implementation Parameters of a Nonlinear Electrical Impedance Tomography Method Using the Complete Electrode Model.

This study discusses a nonlinear electrical impedance tomography (EIT) technique under different analysis conditions to propose its optimal implementation parameters. The forward problem for calculating electric potential is defined by the complete electrode model. The inverse problem for reconstructing the target electrical conductivity profile is presented based on a partial-differential-equation-constrained optimization approach. The electrical conductivity profile is iteratively updated by solving the Karush-Kuhn-Tucker optimality conditions and using the conjugate gradient method with an inexact line search. Various analysis conditions such as regularization scheme, number of electrodes, current input patterns, and electrode arrangement were set differently, and the corresponding results were compared. It was found from this study that the proposed EIT method yielded appropriate inversion results with various parameter settings, and the optimal implementation parameters of the EIT method are presented. This study is expected to expand the utility and applicability of EIT for the non-destructive evaluation of structures.

Validation of the Korean version of the obsession with COVID-19 scale and the Coronavirus anxiety scale.

In response to the current COVID-19 pandemic, the Obsession with COVID-19 scale (OCS) and the Coronavirus Anxiety Scale (CAS) were developed as screening tools for dysfunctional anxiety associated with the coronavirus. These scales have not yet been validated in the East Asia. The present study examined the validity of the OCS and the CAS with a sample of 329 Korean adults. We found that the OCS-Korean and CAS-Korean showed good psychometric properties and construct validity. Developing such valid screening tools across different cultures is vital for health practitioners and scholars alike during global infectious disease outbreaks.

Essentializing happiness reduces one's motivation to be happier.

OBJECTIVE: The present study examined the essentialist lay theories of happiness (i.e., beliefs that happiness is determined by one's genes and hence, immutable) and its implications for motivation to enhance one's happiness level. METHOD: Study 1 (N = 454) developed a scale called the "Essentialist Beliefs about Happiness (EBH)" and Study 2 (N = 207) validated the scale by comprehensively examining conceptually overlapping constructs related to the EBH. In Study 3 (N = 401) and Study 4 (N = 452), by utilizing correlational and experimental methods, we tested the effect of the EBH on motivation to enhance happiness. RESULTS: Using the scale developed and validated in Study 1 and Study 2, Study 3 and Study 4 found that the essentialist beliefs about happiness predicted reduced motivation to be happier. Specifically, participants with greater essentialist beliefs about happiness were less likely to engage in happiness-boosting activities. Specifically, those who believed that happiness is influenced by one's attitude and effort had greater intention to engage in happiness-boosting activities. CONCLUSIONS: The present results provide new insight into the role of individual differences in essentialist lay theories of happiness in motivational state in well-being domain.

Individualism-collectivism during the COVID-19 pandemic: A field study testing the pathogen stress hypothesis of individualism-collectivism in Korea.

The pathogen stress hypothesis posits that pathogen-related threats influence regional and individual differences in collectivism since behavioral practices associated with collectivism limit the spread of infectious diseases. In support of the hypothesis, previous research demonstrates the association between individualism/collectivism and pathogen stress based on historical records or experimental manipulation. However, it is still unclear whether individuals would indeed value collectivism during the outbreak of infectious diseases. Thus, we investigated the concurrent effects of pathogen-related stress on the endorsement of individualism/collectivism by examining 9322 Koreans for 14 weeks of the COVID-19 pandemic. The results revealed that the level of collectivism among respondents were higher after than before the COVID-19 outbreak. Moreover, the average level of collectivism on a given day showed a significant association with the number of confirmed COVID-19 cases on the same day during the outbreak. Interestingly, individualism did not significantly change for the same period.

Investigating Self-Centering Capacity of Superelastic Shape Memory Alloy Fibers with Different Anchorages Through Pullout Tests.

This study investigated the pull-out resistance of superelastic shape memory alloy (SMA) short fibers in mortar with consideration of various end-anchorages that provide different anchoring actions. For the purpose, four types of SMA fibers were prepared using NiTi SMA wires with a diameter of 1.0 mm and the following four end shapes: straight (ST), L-shaped (LS), N-shaped (NS), and spearhead-shaped (SH). The straight-ended fiber was a reference with no working on the end, and the fiber with the spearhead-shaped end was crimped to make the end part flat. The fibers with L- and N-shaped ends were bent with single or double bending. The results showed that only the spearhead-shaped fibers showed self-centering behavior because of the superelasticity of the SMA after slip occurred. This paper discusses the reasons that the ST, LS, and NS fibers do not show self-centering behavior and proposes a concept to induce superelastic behavior in SMA fibers in mortar or concrete.

Nanostructured ZnO films on stainless steel are highly safe and effective for antimicrobial applications.

The safety and effectiveness of antimicrobial ZnO films must be established for general applications. In this study, the antimicrobial activity, skin irritation, elution behavior, and mechanical properties of nanostructured ZnO films on stainless steel were evaluated. ZnO nanoparticle (NP) and ZnO nanowall (NW) structures were prepared with different surface roughnesses, wettability, and concentrations using an RF magnetron sputtering system. The thicknesses of ZnO NP and ZnO NW were approximately 300 and 620 nm, respectively, and ZnO NW had two diffraction directions of [0002] and [01-10] based on high-resolution transmission electron microscopy. The ZnO NW structure demonstrated 99.9% antimicrobial inhibition against Escherichia coli, Staphylococcus aureus, and Penicillium funiculosum, and no skin irritation was detected using experimental rabbits. Approximately 27.2 ± 3.0 µg L-1 Zn ions were eluted from the ZnO NW film at 100 °C for 24 h, which satisfies the WHO guidelines for drinking water quality. Furthermore, the Vickers hardness and fracture toughness of ZnO NW films on stainless steel were enhanced by 11 and 14% compared to those of the parent stainless steel. Based on these results, ZnO NW films on STS316L sheets are useful for household supplies, such as water pipes, faucets, and stainless steel containers.

The relationship between momentary emotions and well-being across European Americans, Hispanic Americans, and Asian Americans.

Cultural differences in the emphasis on positive and negative emotions suggest that the impact of these emotions on well-being may differ across cultural contexts. The present study utilised a momentary sampling method to capture average momentary emotional experiences. We found that for participants from cultural contexts that foster positive emotions (European Americans and Hispanic Americans), average momentary positive emotions predicted well-being better than average momentary negative emotions. In contrast, average momentary negative emotions were more strongly associated with well-being measures for Asian Americans, the group from a cultural context that emphasises monitoring of negative emotions. Furthermore, we found that acculturation to American culture moderated the association between average momentary positive emotions and well-being for Asian Americans. These findings suggest the importance of culture in studying the impact of daily emotional experiences on well-being.

The associations between body dissatisfaction, body figure, self-esteem, and depressed mood in adolescents in the United States and Korea: A moderated mediation analysis.

The perception of one's body image becomes particularly important in adolescence. Body dissatisfaction has been associated with negative psychological functioning, such as self-esteem and depression. Previous findings showed that the decreased self-esteem due to body dissatisfaction explained the association between negative attitude toward body and psychological well-being in different cultural contexts. The present study examined adolescents from the US (N = 1002) and Korea (N = 3993) and replicated and extended the previous findings regarding body dissatisfaction and associated psychological outcomes. The results showed that body dissatisfaction predicted higher depressed mood and that self-esteem mediated this association for both American and Korean adolescents. Notably, the indirect effect of body dissatisfaction and perceived body image on depressed mood via self-esteem was greater for American adolescents than for Korean adolescents. The implications of the cultural difference in the significance of self-esteem in mediating the body dissatisfaction and depressed mood are discussed.

Effect of confining pressure due to external jacket of steel plate or shape memory alloy wire on bond behavior between concrete and steel reinforcing bars.

For external jackets of reinforced concrete columns, shape memory alloy (SMA) wires are easy to install, and they provide active and passive confining pressure; steel plates, on the other hand, only provide passive confining pressure, and their installation on concrete is not convenient because of the requirement of a special device. To investigate how SMA wires distinctly impact bond behavior compared with steel plates, this study conducted push-out bond tests of steel reinforcing bars embedded in concrete confined by SMA wires or steel plates. For this purpose, concrete cylinders were prepared with dimensions of 100 mm x 200 mm, and D-22 reinforcing bars were embedded at the center of the concrete cylinders. External jackets of 1.0 mm and 1.5 mm thickness steel plates were used to wrap the concrete cylinders. Additionally, NiTiNb SMA wire with a diameter of 1.0 mm was wound around the concrete cylinders. Slip of the reinforcing bars due to pushing force was measured by using a displacement transducer, while the circumferential deformation of specimens was obtained by using an extensometer. The circumferential deformation was used to calculate the circumferential strains of the specimens. This study assessed the radial confining pressure due to the external jackets on the reinforcing bars at bond strength from bond stress-slip curves and bond stress-circumferential strain curves. Then, the effects of the radial confining pressure on the bond behavior of concrete are investigated, and an equation is suggested to estimate bond strength using the radial confining pressure. Finally, this study focused on how active confining pressure due to recovery stress of the SMA wires influences bond behavior.

Is reading sexual intention truly functional? The impact of perceiving a partner's sexual intention on courtship initiation behaviors.

The present research examined the presumed but not tested behavioral functions of sexual intent perception. Sex differences in the perception of a partner's sexual intention have been explained by its functions, from an evolutionary perspective, in males' and females' divergent mating goals. Our research directly explored the functional explanation in terms of behavioral impact by testing whether sex differences in sexual intent perception could lead to successful courtship behaviors. In Study 1, 411 college students reported their preferred courtship-initiating behaviors in hypothetical situations in which their own sexual motivation and their perceptions of a potential partner's sexual intention varied. The results showed that females' courtship behaviors were influenced only by their own sexual motivation whereas males' behaviors were influenced by both their own sexual motivation and their perception of a potential partner's sexual intent. Study 2 examined whether a participant's perception of a potential partner's sexual intention resulted in the participant selecting the specific courtship strategies that could eventually lead to successful mating opportunities. We compared the behavioral strategies preferred by courtship initiators (Study 1) to the reactions of courtship targets toward these same strategies (collected from 103 college students in Study 2) when the target's sexual intention and the initiator's perception of it matched. The results showed that only one condition-male initiators whose perception of the target's sexual intent corresponded with the target's actual intent-utilized effective courtship behaviors. The findings were consistent with the functional prediction and their theoretical implications for the evolutionary perspective were discussed.

Effect of adjusted cuff pressure of endotracheal tube during thyroidectomy on postoperative airway complications: prospective, randomized, and controlled trial.

BACKGROUND: Postoperative sore throat (POST) is a common complaint after general anesthesia, especially following thyroidectomy. MATERIALS AND METHODS: We examined the effect of adjusting the endotracheal tube cuff pressure during thyroidectomy on the incidence of airway complications. Ninety patients scheduled for elective thyroidectomy were randomized into two groups: control (group A, n = 45) and experimental (group B, n = 45). All patients underwent total intravenous anesthesia with propofol and remifentanil. In group A, the cuff pressure was set to 25 cm H2O initially and then monitored continuously without adjustment during thyroidectomy. In group B, the cuff pressure was maintained at approximately 25 cm H2O throughout the operation. The incidences and the severity of POST, hoarseness, dysphagia, and cough were recorded at 2 and 24 h postoperatively. RESULTS: Cuff pressures in group A changed significantly over time (P < 0.05) and were higher than those of group B during thyroidectomy (P < 0.05). The incidences of POST were lower in group B than in group A at 2 and 24 h postoperatively (P < 0.05), and there was a significant difference in the severity of POST at 2 h postoperatively between the two groups. There were no differences in the incidences of hoarseness, dysphagia, and cough between the two study groups (P > 0.05). Adjusting the endotracheal cuff pressure during thyroidectomy decreased the incidence and degree of POST. CONCLUSIONS: Intraoperative monitoring and adjustment of the cuff pressure can reduce POST in patients undergoing thyroidectomy.

Gender differences in perceived legitimacy and status perception in leadership role.

The present study examined the difference between women and men in perceiving leadership roles. Two experiments, one conducted online and the other in a lab, investigated the subjective experiences of Japanese men and women when they are assigned with different roles (e.g., leader vs. subordinate). Both studies revealed that women perceived their role as less legitimate when they were assigned leader role (vs. subordinate role). In contrast, men did not differ in their perceived legitimacy according to the assigned roles. This discrepancy in legitimacy perception in response to different roles between men and women accounted for a significant variance in women's lower sense of status when they were a leader (vs. subordinate), but not among men. Our study results illustrate the psychological barrier operating for women in organizations that are embedded in a cultural context in which women leaders are highly underrepresented.

Older people are not always happier than younger people: The moderating role of personality.

The present research explored whether the well-established U-shaped relationship between age and happiness varied with personality. Individuals ranging from 15 to 75 years of age (N = 10,456, 84.9% female) completed online surveys of subjective well-being (i.e. life satisfaction, positive affect, and negative affect) and the Big Five personality traits (International Personality Item Pool [IPIP]). The results of hierarchical multiple regression using the PROCESS macro not only supported the prediction of a U-shaped relationship between age and well-being but also revealed that the quadratic relationship is moderated by agreeableness and neuroticism. Specifically, well-being did not bounce back in later adulthood on the well-being curve across different age groups with low agreeableness and high neuroticism. Moreover, positive affect did not increase and even decreased in later adulthood among those with low agreeableness. This study discusses the potential mechanisms.

Active SMA Fibers' Effect on the Pullout Behavior of a Steel Bar Embedded in Concrete.

This study investigated the bond behavior and radial crack between concrete and reinforcing bars using cold-drawn shape memory alloy (SMA) crimped fibers controlled by the temperature and volume fraction of the fibers. In this novel approach, the concrete specimens containing cold-drawn SMA crimped fibers with 1.0% and 1.5% volume fractions of cold-drawn SMA fibers were prepared. After that, the specimens were heated to 150 °C to generate recovery stress and activate prestressing within the concrete. The bond strength of specimens was estimated by pullout test using the universal testing machine (UTM). Furthermore, the cracking patterns were investigated using radial strain measured by a circumferential extensometer. The results showed that adding up to 1.5% of SMA fibers improved the bond strength by 47.9% and reduced radial strain by more than 54%. Thus, heating specimens containing SMA fibers showed improved bond behavior compared with non-heated specimens with the same volume fraction.

Finite Bending of Fiber-Reinforced Visco-Hyperelastic Material: Analytical Approach and FEM.

This paper presents a new anisotropic visco-hyperelastic constitutive model for finite bending of an incompressible rectangular elastomeric material. The proposed approach is based on the Mooney-Rivlin anisotropic strain energy function and non-linear visco-hyperelastic method. In this study, we aim to examine the mechanical response of a reinforced viscoelastic rectangular bar with a group of fibers under bending. Anisotropic materials are typically composed of one (or more) family of reinforcing fibers embedded within a soft matrix material. This operation may lead to an enhancement in the strength and stiffness of soft materials. In addition, a finite element simulation is carried out to validate the accuracy of the analytical solution. In this research, the well-known stress relaxation test, as well as the multi-step relaxation test, are examined both analytically and numerically. The results obtained from the analytical solution are found to be in good agreement with those from the finite element method. Therefore, it can be deduced that the proposed model is competent in describing the mechanical behavior of fiber-reinforced materials when subjected to finite bending deformations.

Crack Resistance of Prestressed Reinforced Concrete Beams with Wire Rope Reinforcement.

One of the main objectives of capital construction worldwide is to increase the efficiency of construction. To achieve this, a significant improvement in the quality of concrete and reinforced concrete is required. Nowadays, in developed countries, one of the key directions for enhancing the efficiency of concrete and reinforced concrete is reducing their density by using inexpensive and high-quality local porous fillers. In recent years, the use of concrete structures with porous fillers based on ceramporite in load-bearing reinforced concrete structures has allowed for the improvement of their technical and economic indicators and the reduction in their own weight by up to 35%. This, in turn, is considered an essential factor in seismic zones, and therefore, special attention is paid to these issues. This article presents the data of experimental and theoretical studies obtained from investigating the crack resistance of prestressed lightweight reinforced concrete flexural elements with wire rope reinforcement. The main factors influencing crack resistance were considered, including the effects of two types of porous filler (ceramporite), two types of concrete, concrete strength, percentage of reinforcement, and level of precompression. The tests were conducted using short-term and repeated loadings. Based on the analysis of the obtained data, some refinements have been made to the methodology for calculating the crack resistance of such structures according to current design standards.

To drink, or to exercise: That is (not) the question! Daily effects of alcohol consumption and exercise on well-being.

Drinking alcohol and exercising are two of the most popular ways of dealing with stress. Despite the fact that they often co-occur, few studies have examined the role of the two activities together in everyday well-being. The current research aimed to investigate the dynamics between these two daily activities and various indices of well-being in a natural environment by using a daily diary method and ecological momentary assessment. We asked 478 adults to record their alcohol intake, exercising activity, and momentary well-being, three times a day for 2 weeks. Significant detrimental effects of drinking alcohol and beneficial effects of exercising on well-being were observed on the next day, whereas no significant effect of well-being was found on the likelihood of drinking and exercising on the second day. Furthermore, sleep quality was identified as one of the factors influencing the changes of well-being induced by the drinking and exercising engaged in the previous day. The present research allows us to deepen our understanding of the lagged relationship between the daily activities of drinking alcohol/exercising and well-being and demonstrates the underlying mechanism for the observed effects. Theoretical and practical implications are discussed.

Continuous VOCs Monitoring in Saturated and Unsaturated Zones Using Thermal Desorber and Gas Chromatography: System Development and Field Application.

Subsurface VOC monitoring has been mainly based on manual sampling, transport, and analysis, which would require a sufficient amount of samples to ensure data accuracy and reliability, and additional costs to ensure sample quality. Therefore, a continuous on-site monitoring system is desirable for accurate measurement and subsequent risk assessment. In this study, benzene, toluene, ethylbenzene, and xylene (BTEX) were continuously monitored by the system based on a thermal desorber (TD) and gas chromatography (GC) in an oil-contaminated site that consisted of saturated and unsaturated zones. For the saturated zone, fully automated groundwater sampling and purging processes were performed, and the gasified samples were applied to the TD-GC system. For the unsaturated zone, the gaseous sample in the site was directly applied to the TD-GC system. After verifying the accuracy and precision of the monitoring system, the continuous monitoring system was successfully operated for more than a month in the field. The monitoring system used in this study is applicable to other sites for continuous monitoring, thus providing a scientific background for advanced risk assessment and policy development.

Impact of face masks and sunglasses on emotion recognition in South Koreans.

Due to the prolonged COVID-19 pandemic, wearing masks has become essential for social interaction, disturbing emotion recognition in daily life. In the present study, a total of 39 Korean participants (female = 20, mean age = 24.2 years) inferred seven emotions (happiness, surprise, fear, sadness, disgust, anger, surprise, and neutral) from uncovered, mask-covered, sunglasses-covered faces. The recognition rates were the lowest under mask conditions, followed by the sunglasses and uncovered conditions. In identifying emotions, different emotion types were associated with different areas of the face. Specifically, the mouth was the most critical area for happiness, surprise, sadness, disgust, and anger recognition, but fear was most recognized from the eyes. By simultaneously comparing faces with different parts covered, we were able to more accurately examine the impact of different facial areas on emotion recognition. We discuss the potential cultural differences and the ways in which individuals can cope with communication in which facial expressions are paramount.

Gender discrimination in workplace and depressive symptoms in female employees in South Korea.

BACKGROUND: Workplace gender discrimination (WGD) may have long-term negative impacts on female workers' mental health. We aimed to investigate the association between WGD and the prevalence of depressive symptoms using a nationally representative sample of female employees in South Korea. METHODS: Data of 3190 adult female employees were obtained from the 2018 nationwide Korean Longitudinal Survey of Women and Families. Women's perception of WGD was assessed using a 6-item questionnaire. Respondents were classified into high, medium, and low levels of WGD according to the 25th and 75th percentile scores. A score of ≥10 on the 10-item version of the Center for Epidemiologic Studies for Depression Scale was defined as having significant depressive symptoms. RESULTS: A high level of WGD was significantly associated with a higher odds ratio (OR) for depressive symptoms compared to the low level (OR = 1.87, 95% confidence interval = 1.45-2.41). In the subgroup analyses, high WGD levels were associated with the highest OR for depressive symptoms in the following subgroups: younger age (19-39 years), those with a college degree, non-standard workers, pink collar workers, those with a workplace size of 10-29 employees, those with high levels of job autonomy, or low levels of emotional labor. LIMITATIONS: Causal interpretation is limited owing to the study's cross-sectional design. CONCLUSIONS: A high level of perceived WGD was associated with depressive symptoms among female employees. Certain groups of female employees may be particularly vulnerable to the detrimental effects of WGD on depression.