In many systems, the tensors used to describe physical properties must acquire their structure from one vector. Knowledge of that fact alone leads to an interesting line of analysis for such systems. The analysis begins with a discussion of the types of dyadics that can be constructed from one vector. Attention is focused on certain exemplary dyadic operators, which, because of their geometrical properties, would appear particularly basic; the algebra of these dyadics is developed in detail. The algebra is then (...) used in a derivation of the expansion of general functions of these dyadics. Several applications of the general expansion are presented: the inverse of a general dyadic operator (when it exists), a general rotation operator that includes strains and reflections, the determinant of a general dyadic operator, and operators, including some new ones, used in constructing Lorentz boosts. Finally, a coordinate-free representation of the Levi-Civita tensor is provided. (shrink)

The coordinate-free methods of the preceding paper are illustrated in three problems. First, the electrodynamics of a homogeneous, isotropic, and gyrotropic medium is investigated; it is shown that such a medium can exhibit optical activity, and the propagation of a plane electromagnetic wave in such a medium is discussed. Then, the electrodynamics of a homogeneous system made anisotropic by a uniform external magnetic field is considered; a description of Faraday rotation is provided, the ionosphere being used in an example. Finally, (...) the reflection and refraction of a plane electromagnetic wave at the interface of two media are described by coordinate-free operators. (shrink)

Sustainable product-service system (PSS) has potentiality to reduce the environmental stress through dematerialization of economy based on function-based well-being. PSS (also called as service) is a type of human-activity system with a series of events and is produced only after the demand from a consumer. The features of the events influence the consumer to act rationally according to the particular situations. Consumers must have freedom to choose a combination of relieving and enabling model of PSS to act rationally upon those (...) according to the feature of events and the consumers have reasons to value their selection of services. A case of a complete journey of a passenger with urban mobility services is considered to visualize and realize the rational behaviour, which shows a systemic pattern and also autopoietic in nature. (shrink)

Over the last quarter century, the dominant tendency in comparative cognitive psychology has been to emphasize the similarities between human and nonhuman minds and to downplay the differences as (Darwin 1871). In the present target article, we argue that Darwin was mistaken: the profound biological continuity between human and nonhuman animals masks an equally profound discontinuity between human and nonhuman minds. To wit, there is a significant discontinuity in the degree to which human and nonhuman animals are able to approximate (...) the higher-order, systematic, relational capabilities of a physical symbol system (PSS) (Newell 1980). We show that this symbolic-relational discontinuity pervades nearly every domain of cognition and runs much deeper than even the spectacular scaffolding provided by language or culture alone can explain. We propose a representational-level specification as to where human and nonhuman animals' abilities to approximate a PSS are similar and where they differ. We conclude by suggesting that recent symbolic-connectionist models of cognition shed new light on the mechanisms that underlie the gap between human and nonhuman minds. (shrink)

Good balance between product and service is the key in the innovative design of product service systems. In this study, the evolution route of the PSS based on Teoriya Resheniya Izobretatelskikh Zadatch ideal final result was provided. The function model of the PSS was constructed according to the service blueprint and function system diagrams. On this basis, an innovation design method of the PSS based on function incentive was established. The function incentive strategies included function synergy, function supplement, and function (...) substitution. Finally, the PSS design process of agricultural machinery based on computer-aided innovation platform was analyzed to verify this method. (shrink)

The present study tested the impact of attention training on cognition; secondary appraisal of perceived stress, and on metacognition; meta-worry in stressed students. Theoretically derived from the Self-Regulatory Executive Function model (S-REF model; Wells & Matthews, 1994a; 1996), the Attention Training Technique (ATT; Wells, 1990) is intended to promote flexible, voluntary external attention and has been shown to reduce symptoms of psychological distress. The present experimental study explored the effects of ATT on cognitive and metacognitive levels of appraisal, namely perceived (...) stress (primary outcome) and meta-worry (secondary outcome). Stressed students were randomized to an experimental ATT group (n = 23) or a control group (n = 23). The ATT group attended an initial training session followed by four weeks of individual (12 minutes) daily ATT practice. The control group waited for four weeks before receiving the intervention. The outcomes were scores on the Perceived Stress Scale 14 (PSS-14) and the Meta-Worry Questionnaire (MWQ) frequency and belief subscales at post study. Both measures decreased significantly following ATT with large pre to post effect sizes but there were minimal changes in the control group. The between group differences were statistically significant. The results add to the literature on the potential effects of ATT by demonstrating effects on the content of cognitive stress appraisals and on meta-worry in an academic setting in a stressed student sample. (shrink)

The current study examined how the level of perceived stress among women living in Dhaka varies by their degree of social capital and illustrated the relative significance of some of their sociodemographic statuses, such as employment status, marital status, education, and income level, with those variables of interest. In this cross-sectional study, data were collected from a total of 485 women, 243 formally employed (having a tax identification number), and 242 non-employed (50 students and 192 homemakers). Apart from the demographic (...) information, the questionnaire includes statements from Cohen’s perceived stress scale (PSS) and the Internet Social Capital Scale (ISCS). Results indicate that social capital substantially reduces perceived stress, with the effect being particularly apparent among non-employed and unmarried women. While unmarried women experience higher levels of stress compared to married ones, it appears that women’s perceived stress levels do not differ by employment status, education, or income. In addition, there is no significant variation in social capital by marital status or income level; however, it is observed that working women possess higher social capital compared to unmarried women. The study concludes that women’s employment can contribute to their social well-being by enhancing their social capital, but their perceived stress levels may not differ substantially because of their formal employment. (shrink)

Psychotherapy style is conceptualized as the therapeutic method that a therapist employs while working with clients during treatment. It influences both the therapeutic process and results of therapeutic actions. The present study developed and validated the Psychotherapy Style Scale. By following a systematic psychometric development process, a three-factor structure of the PSS was identified. Exploratory factor analysis and confirmatory factor analysis provided evidence of multidimensional structure and validity of the PSS. Cronbach’s α suggested that the resulting scale was highly reliable. (...) Criterion validity was also satisfactory, demonstrated by correlations between the scale and criterion validity measures. The PSS has the potential to help better understand therapists’ behavioral characteristics and select the most appropriate therapists for clients who undergo psychotherapy. (shrink)

Stone, J. Thoughts on supposed "Death of law".--Krishna Iyer, V. R. Jurisprudence and jurisconscience.--Sharma, G. S. Law and social change in India.--Sharma, S. D. The concept of justice in Manu.--Chand, H. Legal values for a developing country.--Ramarao, T. S. The new international law relating to the rights and duties of States.--Sinha, B. S. Custom and customary law in Indian jurisprudence.--Mazumdar, D. L. Techno-economic structure of our industrial society.--Subrahamanian, N. Law and social change.

Introduction: Parental postpartum bonding has been studied by many researchers focusing on maternal bonding. The objective of this study was to examine the psychological and socio-demographic predictors of paternal postpartum bonding in the early postpartum period.Methods: In this cross-sectional study, 131 couples (fathers median age of 32.37 years,SD= 4.59; mothers median age of 30.23 years,SD= 3.90) of newborns from full-term pregnancies were recruited from November 2019 until March 2020. The primary outcome was paternal postpartum bonding as measured by the Postpartum (...) Bonding Questionnaire (PBQ). Secondary outcomes included: maternal and paternal anxiety [with the Generalized Anxiety Disorder (GAD) Assessment]; maternal and paternal stress [with the Parental Stress Scale (PSS)]; maternal depressive symptoms [with the Edinburgh Postpartum Depression Scale (EPDS)]; and maternal and paternal socio-demographic variables as fathers’ presence at childbirth, education level, age, and parental experience.Results: Paternal postpartum bonding was significantly correlated with paternal anxiety (moderate strength), maternal stress (strong correlation), and maternal postpartum bonding. No significant correlations between paternal postpartum bonding, maternal depression symptoms, and maternal anxiety were found. The mediating role of paternal stress in paternal postpartum bonding was proven. Paternal anxiety strengthens paternal stress (b= 0.98). Further, a high level of paternal stress disrupts paternal postpartum bonding (b= 0.41). Results of regression analyses have revelated that maternal infant bonding (p< 0.01) and paternal stress (p< 0.01) are the only predictors of parental postpartum bonding across all included variables. None of investigated socio-demographic variables were associated with paternal postpartum bonding.Conclusion: Notwithstanding limitations, the current findings add to a growing body of literature on paternal postpartum bonding. The results have shown that paternal mental health is related to parental postpartum bonding directly after delivery.Clinical Trial Registration:ClinicalTrials.govIdentifier: NCT04118751. (shrink)

ObjectiveLong-term isolation, including lockdowns and quarantines, may have a distressing effect on anyone experiencing it. Adolescent brain architecture is very sensitive to environmental adversities, and the mental health development of adolescents may be particularly vulnerable during the pandemic era. In order to better understand the triggers for perceived adolescent stress during the COVID-19 lockdown, the present study aimed to assess the effects of social well-being and changes in time use during the lockdown, as well as the family COVID experience of (...) adolescents.MethodsThe sample for this study comprised n = 3,440 adolescents. Bayesian correlations between PSS, health and well-being variables were assessed. PSS was then modeled as an outcome variable in a series of nested Bayesian multilevel regression models.ResultsThe negative impact of the COVID-19 lockdown was more apparent in girls. PSS was moderately correlated with adolescent health and well-being. The strongest predictor of higher level of PSS was frequent feeling of loneliness. On the contrary, lower level of PSS was most associated with having someone to talk to.ConclusionLong-term social isolation of adolescents could be harmful to their mental health. Psychological coping strategies to prevent the consequences of social isolation and development of mental health problems should be promoted on the individual, family, and even community level. (shrink)

O presente estudo teve como objetivo descrever indicadores de saúde emocional de mães de bebês internados, considerando o tempo de internação em Unidade de Terapia Intensiva Neonatal (UTIN). Participaram 50 mães de bebês que estavam internados na UTIN da Maternidade Santa Isabel, em Bauru, SP. Para a caracterização da amostra utilizou-se de um questionário sociodemográfico com informações sobre as mães e os bebês. Para a avaliação da saúde emocional materna utilizou-se da Escala de Estresse Percebido (PSS - 14), o Inventário (...) de Ansiedade Traço-Estado (IDATE) e o Inventário de Depressão de Beck (BDI-II). As mães responderam aos instrumentos em seus quartos ou nas dependências da UTI. Os resultados apontaram para índices mais altos de estresse (38%), ansiedade traço (54%) e ansiedade estado (64%). Das mães, 56% apresentaram dois ou mais indicadores clínicos de saúde emocional. Quanto maior o tempo de internação maior a depressão e a ansiedade estado. Os resultados sugerem atenção terapêutica às mães de bebês em UTIN. (shrink)

AimWe aimed to investigate whether the 12-item Multidimensional Scale of Perceived Social Support (MSPSS) constitutes a valid and reliable measure of social support for the general adult Australian population.MethodsData were from Australia’s National Survey of Adult Oral Health 2004–2006 and included 3899 participants aged 18 years old and over. The psychometric properties were evaluated with Bayesian confirmatory factor analysis. One-, two-, and three-factor (Significant Other, Family and Friends) structures were tested. Model fit was assessed with the posterior predictivep-value (PPPχ2), Bayesian (...) root mean square error of approximation (BRMSEA), and Bayesian comparative fit index (BCFI). Dimensionality was tested by comparing competing factorial structures with the Bayes factor (BF). Reliability was evaluated with the Bayesian ΩH. Convergent validity was investigated with the Perceived Stress Scale (PSS) and discriminant validity with the Perceived Dental Control scale (PDC-3).ResultsThe theoretical three-factor model (Significant Other, Family, and Friends) provided a good fit to the data [PPPχ2< 0.001, BRMSEA = 0.089-95% credible interval (CrI) (0.088, 0.089); BCFI = 0.963-95% CrI (0.963, 0.964)]. The BF provided decisive support for the three-factor structure in relation to the other structures. The SO [BΩH= 0.95 - 95% CrI (0.90, 0.99)], FA (BΩH= 0.92 - 95% CrI (0.87, 0.97), and FR (BΩH= 0.92 - 95% CrI (0.88, 0.97)] subscales displayed excellent reliability. The MSPSS displayed initial evidence of convergent and discriminant validity.ConclusionThe MSPSS demonstrated good psychometric properties and excellent reliability in a large Australian sample. This instrument can be applied in national surveys and provide evidence of the role of social support in the Australian population. (shrink)

The meanings of abstract concepts depend on context. Perceptual symbol systems (PSS) provide a powerful framework for representing such context. Whereas a few expected difficulties for simulations are consistent with empirical findings, the theory does not clearly predict simulations of specific abstract concepts in a testable way and does not appear to distinguish abstract noun concepts (like truth) from their stem concepts (such as true).

Maintaining accurate and precise temporal perception under conditions of stress is important. Studies in animal models and clinic patients have suggested that time perception can change under chronic stress. Little is known, however, about the relationship between chronic stress and time perception in healthy individuals. Here, a sample of 62 healthy young men completed Cohen’s Perceived Stress Scale (PSS) as a measure of chronic stress levels, while time perception was measured using a temporal bisection task. This task used short (400 (...) ms) and long (1600 ms) visual signals as anchor durations. Participants were presented with a range of intermediate probe durations and were required to judge whether the durations were more similar to the short or the long anchor. Results showed that chronic stress was negatively related to temporal sensitivity indexed by the Weber ratio. However, there was no significant correlation between chronic stress and subjective duration indexed by the bisection point. These results demonstrate that higher chronic stress is associated with lower temporal sensitivity and thus provide evidence for a link between chronic stress and time perception in healthy adults. (shrink)

The requirement that theoretical and empirical research is to sustainably benefit not only the nominal researcher, but also the other research participants, is deeply embedded in the conceptual-analytical framework of Psychology from the Standpoint of the Subject and its co-researcher principle. PSS research is thus to be of emancipatory relevance to those others the researcher comes to collaborate with. Meanwhile, the question of how this requirement can be prospectively integrated into the design of a research project remains subject to debate. (...) This question emerges as particularly difficult to tackle in research projects that engage in co-research with young children: How can a researcher ensure that the young children s-he works togethe with benefit from the research project? Based on the critical analysis of an earlier research project implemented by the author, the contribution at hand suggests that PSS’ foundational notion of emancipatory relevance needs to be revisited. It argues that if a research project is to sustainably benefit young co-researchers, the technical relevance of the expected mutual emancipation should as well be explicitly considered in the project design. A discussion of recent methodological developments in child-targeted Participatory Design and Human-Computer Interaction serve as inspiration for this conceptual specification. The contribution thereby invites co-research to further investigate how emancipatory relevance cannot only to be methodologically attained via dissemination of research results and conceptual developments, but also via the actual research process it attempts to engage the co-researchers in irrespective of their age. (shrink)

Background: The rapid spread of COVID-19 infection has led countries across the globe to take various measures to contain the outbreak, including the closure of Universities. Forcing University students to stay at home has created enormous stress and uncertainty in their daily life.Objective: This study aimed to assess the perceived stress and coping strategies among undergraduate health science students of Jimma University amid the COVID-19 outbreak.Materials and methods: An online cross-sectional survey was conducted involving 337 undergraduate health science students from (...) August to September 5, 2020. The perceived stress scale -10 and Brief-COPE scale were used to assess the level of stress and coping strategies, respectively. Statistical Package for Social Science Version 22 was employed for data analysis. Logistic regression was conducted to identify predictors of high perceived stress.Results: The overall mean [±standard deviation ] age of the participants was 22.88 years. The mean PSS score was 22.16, and high perceived stress was reported in 121 participants. The overall mean coping score was 72.34, and approach coping was the predominantly used strategy for coping with stress. Personal perception of being stressed by the daily number of COVID-19 cases/deaths in Ethiopia, rare online talk/chat with friends, presence of confusion due to the inconsistent strategies developed by the health/government authorities in view of the scientific recommendations, perception of self/family members being at risk of getting sick, decreased household income following the COVID-19 pandemic, practicing denial, self-blame, planning, and religion as means of coping with stress were associated with high perceived stress.Conclusion: Over one-third of the participants had a high level of perceived stress, and the majority of them were practicing effective means of coping with stress. The authors recommend that the hosting University in collaboration with the concerned bodies develop innovative strategies to improve the psychological well-being of the students. (shrink)

This paper defends a view of the Gene Ontology (GO) and of Basic Formal Ontology (BFO) as examples of what the manufacturing industry calls product-service systems. This means that they are products (the ontologies) bundled with a range of ontology services such as updates, training, help desk, and permanent identifiers. The paper argues that GO and BFO are contrasted in this respect with DOLCE, which approximates more closely to a scientific theory or a scientific publication. The paper provides a detailed (...) overview of ontology services and concludes with a discussion of some implications of the product-service system approach for the understanding of the nature of applied ontology. Ontology developer communities are compared in this respect with developers of scientific theories and of standards (such as W3C). For each of these we can ask: what kinds of products do they develop and what kinds of services do they provide for the users of these products? (shrink)

Nature-inspired optimization techniques are useful tools in electrical engineering problems to minimize or maximize an objective function. In this paper, we use the firefly algorithm to improve the optimal solution for the problem of directional overcurrent relays (DOCRs). It is a complex and highly nonlinear constrained optimization problem. In this problem, we have two types of design variables, which are variables for plug settings (PSs) and the time dial settings (TDSs) for each relay in the circuit. The objective function is (...) to minimize the total operating time of all the basic relays to avoid unnecessary delays. We have considered four models in this paper which are IEEE (3-bus, 4-bus, 6-bus, and 8-bus) models. From the numerical results, it is obvious that the firefly algorithm with certain parameter settings performs better than the other state-of-the-art algorithms. (shrink)

BackgroundIn this study, we analyze the association of social isolation in the first phase of the pandemic with perceived stress among residents of Poland and Italy with a look at how these populations adjust to and comply with implemented regulations, guidelines, and restrictions.Materials and MethodsInternet survey with Perceived Stress Scale (PSS-10) and questions regarding mobility patterns, attitude, and propensity to adjust toward the implemented measures and current health condition was made among Polish and Italian residents (Cronbach’s alpha 0.86 and 0.79, (...) respectively). The sample size was 7,108 (6,169 completed questionnaires in Poland and 939 in Italy).ResultsThe Polish group had a higher stress level than the Italian group (mean PSS-10 total score 22,14 vs 17,01, respectively;p< 0.01). There was a greater prevalence of chronic diseases among Polish respondents. Italian subjects expressed more concern about their health, as well as about their future employment. Italian subjects did not comply with suggested restrictions as much as Polish subjects and were less eager to restrain from their usual activities (social, physical, and religious), which were more often perceived as “most needed matters” in Italian than in Polish residents.ConclusionHigher activity level was found to be correlated with lower perceived stress, but the causality is unclear. Difference in adherence to restrictions between Polish and Italian residents suggests that introducing similar lockdown policies worldwide may not be as beneficial as expected. However, due to the applied method of convenience sampling and uneven study groups, one should be careful with generalizing these results. (shrink)

The changes and general alarm of the current COVID-19 pandemic have amplified the sense of precariousness and vulnerability for family members who, in addition to the emotional trauma of the cancer diagnosis, add the distress and fear of the risks associated with infection. The primary objectives of the present study were to investigate the psychological impact of the COVID-19 pandemic on the parents of pediatric cancer patients, and the level of stress, anxiety, and the child’s quality of life perceived by (...) the parents during the COVID-19 epidemic. The parents of 45 consecutive children with solid and hematological tumors were enrolled. Four questionnaires were administered to the parents at the beginning of the pandemic lockdown. A 75% of parents exhibited remarkable levels of anxiety, with 60 subjects in state scale and 45 subjects in trait scale having scores that reached and exceeded the STAI-Y cut off. The bivariate matrix of correlation found a significant positive correlation between the IES-R and PSS scores. There was a positive correlation between the PSS and PedsQL scale and a negative correlation between IES-R and STAI-Y. The results confirm that parents of pediatric cancer patients have a high psychological risk for post-traumatic symptoms, high stress levels, and the presence of clinically significant levels of anxiety. (shrink)

ObjectivePhysical isolation measures, known as lockdown or shelter-in-place, experienced during coronavirus disease 2019 have the potential to cause psychological distress. This study was conducted to examine parents’ perceived stress and whether reports of rewards and challenges during lockdown impact stress.MethodsData were collected using a cross-sectional online survey in New South Wales, Australia, across the 4-week lockdown. The survey was completed by 158 parents of children aged under 6 years. Stress was measured using the short form of the Perceived Stress Scale. (...) Rewards and challenges were reported in response to two open-ended questions.ResultsThere was a weak negative correlation between PSS-4 scores and days in isolation, with parents who had spent longer in isolation reporting fewer stress symptoms. The relationship between time in isolation and stress was moderated by the degree to which parents described more rewards than challenges: parents who perceived high rewards and low challenges reported lower PSS-4 scores with more days in lockdown, whereas parents who perceived low rewards and high challenges reported higher PSS-4 scores with more days in lockdown. The moderation model examining associations between time in isolation and rewards ratio explained 13% of the variance in PSS-4 scores.ConclusionLockdowns are not uniformly or consistently negative experiences for parents. Identifying positive aspects of the experience may serve to buffer negative mental health risks across time. Understanding resilience strategies is critical for supporting current psychological wellbeing and to adequately prepare for future pandemic experiences. (shrink)

ObjectiveTo explore the relations among perceived stress, fatigue, sleepiness, and the pathway of their effects on the ambulatory arterial stiffness index among medical staff.MethodsThis cross-sectional study was conducted at a tertiary hospital in Wuhan, China. Perceived stress, fatigue, and sleepiness were measured using the perceived stress scale, Fatigue assessment scale, and Epworth Sleepiness Scale, respectively. AASI was obtained from 24-h ambulatory blood pressure monitoring. Path analysis was used to clarify the relations among the PSS, FAS, and ESS scores, and their (...) relations to AASI values.ResultsA total of 153 participants were included herein. The PSS and FAS correlated with the ESS, and the PSS correlated with the FAS. In addition, the ESS correlated with the AASI. According to the path analysis results, the PSS and FAS had no direct effect on the AASI, but did have an indirect effect on this index by influencing the ESS.ConclusionSleepiness was a mediator of the effects of perceived stress and fatigue on AASI. (shrink)

Competitive sports involve physiological, technical and psychological skills, which influence directly on individuals’ performance. This study aims to investigate the levels of perceived stress and Heart Rate Variability before and after matches with victory and defeat in professional eSports athletes. Our hypothesis was that the winners would have better autonomic and stress responses after match, thus corroborating the literature on neurocardiac connections. Fifty male eSport players were selected players from 10 different Brazilian teams. The experiment was carried out in 2 (...) sessions. Firstly, after signing the informed consent form, 24 h before the game, anthropometric, physical activity levels and time of expertise data were recorded only for sample characterization and the players were familiarized with the perceived stress scale—10 and the HRV measurements. Secondly, players performed the PSS-10 and HRV recording at rest by 10 min 60 and 30 min before the game and 10 min after the end of the game. Overall, concerning PSS-10 our findings show that VG had significant reduced scores in post-game time compared to baseline and pre-game times, while DG had significant increased scores in post-game time compared to BL and pre-game times. Regarding HRV, our results demonstrate that VG had significant increase in RR, SDNN, rMSSD, pNN50 and HF, and significant decrease in LF and LF/HF, while DG had a significant decrease in RR, SDNN, rMSSD and HF, and significant increase in LF and LF/HF. It was observed that VG had better HRV responses as well as lower levels of perceived stress, while DG had worst HRV responses and higher levels of perceived stress. (shrink)

The goal of this study is analyse the influence of perceived supervisor support (PSS) by employees at a micro level and the role of the cultural values of “power distance” and “masculinity” at a macro level on direct employee participation in decision making (PDM). Furthermore, the influence of the gender of managers and employees is taken into account. The analysis is based upon the Sixth European Working Conditions Survey carried out by Eurofound in 2016. The results of a Hierarchical linear (...) model indicate that all predictors significantly influenced PDM and PSS positively and cultural values negatively. When the gender of managers and employees is considered, the findings suggest that PSS has a larger impact on PDM when male managers address female employees. Regarding the moderating effect of PSS on cultural values, it is shown that masculinity and power distance lose importance when employees have the support of their supervisors. (shrink)

With increasing market competition and rapid development of service economy, more and more enterprises are shifting from providing products or services to providing product-service systems that integrate products and services, in order to improve competitiveness and profitability. Meanwhile, consumers have strategic delayed purchasing behavior when purchasing the PSS and high requirements for service quality. This paper investigates the two-period pricing and service quality decisions of product-service supply chain considering consumers’ strategic behavior under decentralized and centralized scenarios. The equilibrium results are (...) compared in two scenarios. In order to eliminate performance loss under the decentralized scenario, we design two-period dynamic contracts to coordinate the PSSC. Furthermore, numerical simulation is provided to verify the feasibility of the contracts. The following conclusions can be drawn: the higher the service input-efficiency, the more beneficial for alleviating consumers’ strategic purchase behavior under two scenarios, but this mitigation effect is more obvious under the centralized scenario. Compared with the centralized scenario, the service quality is lower, the two-period PSS sales prices are higher, and the two-period profit is lower under the decentralized scenario. The proportion of service valuation will promote the widening of the service quality gap under two scenarios, but in some cases, the service input-efficiency will weaken the promotion effect of the proportion of service valuation. The design of the two-period combined contracts depends on the proportion of service valuation. When the proportion of service valuation is high, the “two-period revenue sharing + service-cost sharing” combined dynamic contract can achieve PSSC perfect coordination. However, when the proportion of service valuation is low, it is necessary to design complexity combined dynamic contract which can achieve PSSC perfect coordination. (shrink)

The aim of this study was to compare medical and social sciences students’ outcomes in terms of self-perceived stress, quality of life, and personality traits. We put particular emphasis on external and internal differences in students of specific fields–medicine, nursing, psychology, and pedagogy. In a survey, 1,783 students from Medical University of Gdańsk and University of Gdańsk participated in our study, of whom 1,223 were included in the final statistical analysis. All of them were evaluated using valid and reliable questionnaires–TIPI-PL, (...) PSS-10, and a one-item scale of quality of life. Stress turned out to have a negative effect on quality of life, regardless of the type of field of study. Moreover, students from different fields varied in terms of personality factors: conscientiousness, agreeableness, openness to experience, and emotional stability. In conclusion, many students regardless of their field suffer from high stress and report low quality of life, which potentially further affects their academic performance and social life. (shrink)

A new approach to policy analysis is formulated within the framework of the graph model for conflict resolution. A policy is defined as a plan of action for a decision maker (DM) that specifies the DM’s intended action starting at every possible state in a graph model of a conflict. Given a profile of policies, a Policy Stable State (PSS) is a state that no DM moves away from (according to its policy), and such that no DM would prefer to (...) change its policy given the policies of the other DMs. The profile of policies associated to a PSS is called a Policy Equilibrium. Properties of PSSs are developed, and a refinement is suggested that restricts DMs to policies that are credible in that they are in the DM’s immediate interest. Relationships with existing stability definitions in the graph model for conflict resolution are then explored. (shrink)

BackgroundMental stress and imbalance of its two neural stress systems, the autonomic nervous system and the hypothalamic–pituitary–adrenal axis, are associated with chronic prostatitis/chronic pelvic pain syndrome and erectile dysfunction. However, the comprehensive analyses of psychological stress and stress systems are under-investigated, particularly in CP/CPPS patients complicated by lower urinary tract symptoms and ED.Materials and methodsParticipants were 95 patients in CP/CPPS+ED group, 290 patients in CP/CPPS group, 124 patients in ED group and 52 healthy men in control group. The National Institutes (...) of Health Chronic Prostatitis Symptom Index, the International Index of Erectile Function-5 and the International Prostate Symptom Score were used for assessing the disease severity of CP/CPPS, LUTS and ED. Psychometric self-report questionnaires including the Beck Anxiety Inventory, Perceived Stress Scale, Type A Personality Test and Symptom Checklist 90 were completed for distress from physical symptoms. Twenty-five subjects per group were randomly selected for further investigating the changes of the HPA axis and ANS. Saliva samples were taken on 3 consecutive days at 8 specific times with strict reference to time of morning awakening for evaluation of free cortisol. Heart rate variability as marker of the ANS was measured using 24 h electrocardiography, and time-and frequency-domain variables were analyzed.ResultsThe BAI and SCL-90 scores were significantly higher in the CP/CPPS+ED, CP/CPPS and ED groups compared with the control group. The PSS scores of both groups with ED were significantly higher than the control group. Compared with the CP/CPPS group, the differences of PSS, SCL-90 and TAPT scores were statistically significant in CP/CPPS+ED patients. The IPSS scores were shown to have significantly positive correlations with BAI, PSS and SCL-90 in the CP/CPPS patients. However, in all subjects, the IIEF-5 scores were shown to have significantly negative correlations with BAI, PSS, SCL-90 and quality of life score in NIH-CPSI. Cortisol awakening response parameters and diurnal cortisol levels did not significantly vary between the four groups. Time-dependent parameters of HRV also did not differ significantly across groups. In the frequency domain analysis, low frequency was significantly lower in ED patients when compared with CP/CPPS+ED patients and healthy controls, high frequency power was significantly higher in healthy controls compared to patients with ED, CP/CPPS and CP/CPPS+ED, and the CP/CPPS+ED group had significantly higher LF/HF ratio than the control group.ConclusionCP/CPPS and ED patients score exceedingly high on most psychosocial variables. The symptom scores of LUTS and ED positively correlate with the severity of psychological stress. Our findings also suggest that the ANS sympathovagal imbalance is associated with ED and LUTS in CP/CPPS, whereas HPA axis activity is not. (shrink)