The ectoplasmic specialization (ES) is a testis‐specific, actin‐based hybrid anchoring and tight junction. It is confined to the interface between Sertoli cells at the blood–testis barrier, known as the basal ES, as well as between Sertoli cells and developing spermatids designated the apical ES. The ES shares features of adherens junctions, tight junctions and focal contacts. By adopting the best features of each junction type, this hybrid nature of ES facilitates the extensive junction‐restructuring events in the seminiferous epithelium during spermatogenesis. (...) For instance, the α6β1‐integrin–laminin 333 complex, which is usually limited to the cell–matrix interface in other epithelia to facilitate cell movement, is a putative apical ES constituent. Furthermore, JAM‐C and CAR, two tight junction integral membrane proteins, are also components of apical ES involving in spermatid orientation. We discuss herein the mechanisms that maintain the cross‐talk between ES and blood–testis barrier to facilitate cell movement and orientation in the seminiferous epithelium. BioEssays 29: 36–48, 2007. © 2006 Wiley Periodicals, Inc. (shrink)

In the seminiferous tubule of the mammalian testis, one type A1 spermatogonium (diploid, 2n) divides and differentiates into 256 spermatozoa (haploid, n) during spermatogenesis. To complete spermatogenesis and produce ∼150 × 106 spermatozoa each day in a healthy man, germ cells must migrate progressively across the seminiferous epithelium yet remain attach to the nourishing Sertoli cells. This active cell migration process involves precisely controlled restructuring events at the tight (TJ) and anchoring junctions at the cell–cell interface. While the hormonal events (...) that regulate spermatogenesis by follicle‐stimulating hormone and testosterone from the pituitary gland and Leydig cells, respectively, are known, less is known about the mechanism(s) that regulates junction restructuring during germ cell movement in the seminiferous epithelium. The relative position of tight (TJs) and anchoring junctions in the testis is of interest. Sertoli cell TJs that constitute the blood–testis barrier (BTB) are present side by side with anchoring junctions and are adjacent to the basement membrane. This intimate physical association with the TJs, the anchoring junctions and the basement membrane (a modified form of extracellular matrix, ECM) suggests a role for the ECM in the junction dynamics of the testis. Indeed, evidence is accumulating that ECM proteins are crucial to Sertoli cell TJ dynamics. In this review, we discuss the pivotal role of tumor necrosis factor α (TNFα) on BTB dynamics via its effects on the homeostasis of ECM proteins. In addition, discussion will also be focused on the novel findings regarding the role of non‐basement‐membrane‐associated ECM proteins and components of focal adhesion (a cell–matrix anchoring junction type) in the regulation of junction dynamics in the testis. BioEssays 26:978–992, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

The concept of rectifying names [cheng-ming] is a familiar one in the Confucian Analects. It occupies an important, if not central, position in the political philosophy of Confucius. Since, according to Confucius, the rectification of names is the basis of the establishment of social harmony and political order, one might suspect that later political theories of Confucian-ists should be traced back to the Confucian doctrine of rectifying names. It need not be added that the theory of rectifying names, as (...) developed by Hsün Tzu in the third century B. C., served the double purpose of strengthening his political doctrine of government on the one hand and repudiating doctrines of names on the other. (shrink)

We discuss the relation of the Theory of Event Coding (TEC) to a computational model of expert perception, CHREST, based on the chunking theory. TEC's status as a verbal theory leaves several questions unanswerable, such as the precise nature of internal representations used, or the degree of learning required to obtain a particular level of competence: CHREST may help answer such questions.

Much of early western research has focused on identity. A primed identity can inhibit the priming of other alternative identities, and also negatively affect the intention to purchase products related to those alternative identities. In western culture, individuals operate within a cultural framework that makes them more likely to prioritize their own goals and less likely to rely on environmental factors when evaluating others. Individuals are more likely to choose products that fit their primed identity. In this study, we suggest (...) that in collectivist Chinese culture, individuals may give priority to group-level goals and attach more importance to situational factors when evaluating others. Therefore, a primed identity may not necessarily inhibit the priming of alternative identities. In this research, we examine the association between a focal identity and alternative identities, with particular emphasis on the accessibility, discrepancies, and effects on purchase intention of alternative identities. We also examine the intent to purchase products related to the alternative identity vs. the focal identity, developing a model with which to explore this construct. We test four hypotheses through experiments using an online questionnaire and analyzing the resulting data using statistical product service solutions 22.0 and the PROCESS macro modeling tool. The results are as follows: First, the association between a focal identity and alternative identity has a positive impact on the accessibility of the alternative identity. The clearer the alternative identity is, the greater the impact of the association between the focal identity and alternative identity on the latter’s accessibility. Second, the accessibility of the alternative identity has a positive impact on the intent to purchase alternative identity vs. focal identity-related products. The greater the discrepancy between the focal identity and the alternative identity, the greater the impact on the intent to purchase alternative identity vs. focal identity-related products. The results of this study confirmed the interaction between identity association and the clarity of the alternative identity, as well as the influence of the accessibility of the alternative identity on the intent to purchase alternative identity vs. focal identity-related products. We contribute to the development of a theory on intention to purchase identity-related products. (shrink)

Objectives: To study the attitudes of both medical and non-medical students towards the do-not-resuscitate decision in a university in Hong Kong, and the factors affecting their attitudes.Methods: A questionnaire-based survey conducted in the campus of a university in Hong Kong. Preferences and priorities of participants on cardiopulmonary resuscitation in various situations and case scenarios, experience of death and dying, prior knowledge of DNR and basic demographic data were evaluated.Results: A total of 766 students participated in the study. There were statistically (...) significant differences in their DNR decisions in various situations between medical and non-medical students, clinical and preclinical students, and between students who had previously experienced death and dying and those who had not. A prior knowledge of DNR significantly affected DNR decision, although 66.4% of non-medical students and 18.7% of medical students had never heard of DNR. 74% of participants from both medical and non-medical fields considered the patient’s own wish as the most important factor that the healthcare team should consider when making DNR decisions. Family wishes might not be decisive on the choice of DNR.Conclusions: Students in medical and non-medical fields held different views on DNR. A majority of participants considered the patient’s own wish as most important in DNR decisions. Family wishes were considered less important than the patient’s own wishes. (shrink)

This research explores the harmful effects of negative workplace gossip (NWG) on targets and organizations, including its impacts on helping behavior and knowledge hiding. The mediating role of guanxi closeness and the moderating role of need for affiliation are also examined. The study, based on conservation of resources theory, collected data from 526 employees in the hospitality industry in China, using a three-wave survey design. Hierarchical multiple regression analysis was employed to test the hypotheses. The empirical results showed that NWG (...) was a strong predictor of reduced helping behavior and increased knowledge hiding; and that guanxi closeness mediated both the negative relationship between NWG and helping behavior, and the positive relationship between NWG and knowledge hiding. Additionally, need for affiliation was shown to act as a moderator between NWG and guanxi closeness: high need for affiliation amplified the negative impact of NWG on guanxi closeness, and then further affected employees’ helping behavior and knowledge hiding. This study therefore offers an important new perspective for interpreting the detrimental effects of negative gossip in organizations, providing not just theoretical advances but practical ways in which managers can proactively reduce these impacts. (shrink)

This study examines why and when negative workplace gossip promotes self-serving behaviors by the employees being targeted. Using conservation of resources theory, we find that targets tend to increase their political acts as a result of ego depletion triggered by negative gossip. We also show that sensitivity to interpersonal mistreatment and moral disengagement moderate this process. Specifically, we demonstrate that targets with high levels of sensitivity to interpersonal mistreatment are more likely to experience ego depletion, and that targets with high (...) levels of moral disengagement will find it easier to persuade themselves to engage in political acts. We conducted a three-wave time-lagged survey of 265 employees in Guangdong, China, to test our hypotheses. The results support our theoretical model and indicate that COR theory can be used to explain the impacts of negative workplace gossip. Alongside our important and timely theoretical contributions, we provide new perspectives on how managers can avoid or mitigate these political acts. (shrink)

Previous studies have demonstrated positive correlations between children’s interpersonal trust and social adjustment. However, the psychological mechanism underlying this effect is still unclear. The current study tested the indirect roles of teacher–student relationships from both students’ and teachers’ perspectives in a Chinese context. In total, 709 pupils from grade three to grade five, and their 17 head teachers from a Chinese public primary school participated in this study. The Children’s Generalized Trust Beliefs Scale, Social Adjustment Scale for Children and Adolescents, (...) and Teacher–Student Relationship Questionnaire were used in this study. All these variables were correlated with each other. Structural equation models showed that the interpersonal trust indirectly influenced social adjustment through the teacher–student relationship from students’ perspectives, while the teacher–student relationship from teachers’ perspectives did not play an indirect role. These findings suggest that the teacher–student relationship perceived by students is more important for children’s social adjustment than that perceived by teachers. Both parents and teachers should pay more attention to developing children’s interpersonal trust, build better teacher–student relationships, and focus more on how children feel about the relationship. (shrink)

This paper offers theoretical-cum-practical analyses and reflections on neo-Aristotelian character education, which has gained considerable momentum and popularity in the Western moral education arena in the last 15 years, yet is not attracting much interest in Chinese academia. Based on a literature review of some of the most representative works of neo-Aristotelian character education, such as those of the Jubilee Centre, in combination with the authors’ observations and reflections on Chinese moral education, this paper presents ten possible reasons to explain (...) the ‘unpopularity’ of neo-Aristotelian character education in China. Five out of the ten reasons are theoretical, including the misalignments of educational goals, educational content, virtue thinking styles, expectations/assumptions of moral development and conceptual issues; two reasons are mostly practical, including educational strategies and practical challenges regarding the actualisation and prioritisation of moral education in schools. We also mention one general language-barrier reason, one cultural reason and one disciplinary reason. (shrink)

Truth diagrams are introduced as a novel graphical representation for propositional logic. To demonstrate their epistemic efficacy a set of 28 concepts are proposed that any comprehensive representation for PL should encompass. TDs address all the criteria whereas seven other existing representations for PL only provide partial coverage. These existing representations are: the linear formula notation, truth tables, a PL specific interpretation of Venn Diagrams, Frege’s conceptual notation, diagrams from Wittgenstein’s Tractatus, Pierce’s alpha graphs and Gardner’s shuttle diagrams. The comparison (...) of the representations succeeds in distinguishing ideas that are fundamental to PL from features of common PL representations that are somewhat arbitrary. (shrink)

The representational epistemic approach to the design of visual displays and notation systems advocates encoding the fundamental conceptual structure of a knowledge domain directly in the structure of a representational system. It is claimed that representations so designed will benefit from greater semantic transparency, which enhances comprehension and ease of learning, and plastic generativity, which makes the meaningful manipulation of the representation easier and less error prone. Epistemic principles for encoding fundamental conceptual structures directly in representational schemes are described. The (...) diagrammatic recodification of probability theory is undertaken to demonstrate how the fundamental conceptual structure of a knowledge domain can be analyzed, how the identified conceptual structure may be encoded in a representational system, and the cognitive benefits that follow. An experiment shows the new probability space diagrams are superior to the conventional approach for learning this conceptually challenging topic. (shrink)

The vigorous development of online education has produced massive amounts of education data. How to mine and analyze education big data has become an urgent problem in the field of education and big data knowledge engineering. As for the dynamic learning data, knowledge tracing aims to track learners’ knowledge status over time by analyzing the learners’ exercise data, so as to predict their performance in the next time step. Deep learning knowledge tracking performs well, but they mainly model the knowledge (...) components while ignoring the personalized information of questions and learners, and provide limited interpretability in the interaction between learners’ knowledge status and questions. A context-aware attentive knowledge query network model is proposed in this paper, which combines flexible neural network models with interpretable model components inspired by psychometric theory. We use the Rasch model to regularize the embedding of questions and learners’ interaction tuples, and obtain personalized representations from them. In addition, the long-term short-term memory network and monotonic attention mechanism are used to mine the contextual information of learner interaction sequences and question sequences. It can not only retain the ability to model sequences, but also use the monotonic attention mechanism with exponential decay term to extract the hidden forgetting behavior and other characteristics of learners in the learning process. Finally, the vector dot product is used to simulate the interaction between the learners’ knowledge state and questions to improve the interpretability. A series of experimental results on 4 real-world online learning datasets show that CAKQN has the best performance, and its AUC value is improved by an average of 2.945% compared with the existing optimal model. Furthermore, the CAKQN proposed in this paper can not only track learners’ knowledge status like other models but also model learners’ forgetting behavior. In the future, our research will have high application value in the realization of personalized learning strategies, teaching interventions, and resource recommendations for intelligent online education platforms. (shrink)

The practice of critical care medicine has long been a difficult task for most critical care physicians in the densely populated city of Hong Kong, where we face limited resources and a limited number of intensive care beds. Our triage decisions are largely based on the potential of functional reversibility of the patients. Provision of graded care beds may help to relieve some of the demands on the intensive care beds. Decisions to forego futile medical treatment are frequently physician-guided family-based (...) decisions, which is quite contrary to the Western focus on patient autonomy. However, as people acquire knowledge about health care and they become more aware of individual rights, our critical care doctors will be able to narrow the gaps between the dif ferent concepts of medical ethics among our professionals as well as in our society. An open and caring attitude from our intensivists will be important in minimizing the cross-cultural conflict on the complex issue of medical futility. (shrink)

Six characteristics of effective representational systems for conceptual learning in complex domains have been identified. Such representations should: (1) integrate levels of abstraction; (2) combine globally homogeneous with locally heterogeneous representation of concepts; (3) integrate alternative perspectives of the domain; (4) support malleable manipulation of expressions; (5) possess compact procedures; and (6) have uniform procedures. The characteristics were discovered by analysing and evaluating a novel diagrammatic representation that has been invented to support students' comprehension of electricity—AVOW diagrams (Amps, Volts, Ohms, (...) Watts). A task analysis is presented that demonstrates that problem solving using a conventional algebraic approach demands more effort than AVOW diagrams. In an experiment comparing two groups of learners using the alternative approaches, the group using AVOW diagrams learned more than the group using equations and were better able to solve complex transfer problems and questions involving multiple constraints. Analysis of verbal protocols and work scratchings showed that the AVOW diagram group, in contrast to the equations group, acquired a coherently organised network of concepts, learnt effective problem solving procedures, and experienced more positive learning events. The six principles of effective representations were proposed on the basis of these findings. AVOW diagrams are Law Encoding Diagrams, a general class of representations that have been shown to support learning in other scientific domains. (shrink)

High turnover rate is one of the striking features of the hotel industry and one of the most significant challenges. High turnover rate causes substantial costs for recruitment, selection and training in hotels, on the other hand, it also leads to negative consequences such as the decline of organizational performance and service quality. Thus, it is necessary to search for the root causes of turnover and put forward solutions. This study was designed to examine the impact of psychological capital, organizational (...) commitment, and job satisfaction on turnover intention among hotel employees. Additionally, it aimed to test the mediating roles of job satisfaction and organizational commitment. The data were obtained from 228 hotel customer-contact employees with a time lag of two weeks in three waves in Kuala Lumpur based on convenience sampling. A series of structural equation modeling analyses were utilized to investigate hypothesized relationships. The results reveal that there exists a significant and negative impact of PsyCap on employees’ turnover intention and this correlation is partially mediated through two job attitudes. That is to say, to retain hotel talents, five-star hotel management should take proper measures to help employees obtain and maintain positive psychological resources such as PsyCap, on the other hand, how to cultivate positive job attitudes and strengthen their sense of identification and belonging for their organizations is supposed to be more focused on. (shrink)

It is shown that the usual procedures of obtaining the macroscopic Maxwell equations from the microscopic Maxwell-Lorentz equations by performing averages contain an arbitrary choice of gauge. By a suitable different choice of the gauge the so-obtained Maxwell equations can be cast back to the form of the starting Maxwell-Lorentz equations. Therefore one cannot consider the Maxwell equations to be obtainable from the Maxwell-Lorentz equations by simply performing averages. The implication of this result is that besides the electromagnetic fields produced (...) by the moving electric charges, as given by the Maxwell-Lorentz equations, there may be some other agents that cannot be identified as some kind of motion of the electric charges and that participate in the production of the electromagnetic fields. (shrink)

Out of 288 Hong Kong cancer patients, 92.3% include themselves in decision-making, 71% prefer joint decision-making: with family, with doctor, with doctor plus family, with family minus doctor, and with doctor minus family. <5% want decision-making by “doctor-alone” and <1% desire decision-making by “family-alone”. Harmony, communication and responsibility are reasons for family participation. Most patients prefer “specialist” for information, followed by “family”, “friends”, and “GP”. Trust in doctors and prospects for controlling/curing disease are important factors in decision-making. Patients want to (...) participate and be listened to rather than make decisions. Doctors should not disclose information to family without patients’ permission, nor withhold information from patient [End Page 109] on family’s request. Only 25% of patients have discussed post-competent treatment with others and 7% have heard of Advance Directive ; 24% refuse to discuss it. After AD has been explained to them, 66% remain reluctant to sign one, preferring to leave oral instructions or appoint family as proxy decision-makers. The family’s decision-making role increases when patients become incompetent. The top reason for signing AD is to receive preferred post-competent treatments, and for not signing it, difficulty with making a prospective decision. The implications of these findings will be discussed. (shrink)

Pioneering work in the 1940s and 1950s suggested that the concept of chunking might be important in many processes of perception, learning and cognition in humans and animals. We summarize here the major sources of evidence for chunking mechanisms, and consider how such mechanisms have been implemented in computational models of the learning process. We distinguish two forms of chunking: the first deliberate, under strategic control, and goal-oriented; the second automatic, continuous, and linked to perceptual processes. Recent work with discrimination-network (...) computational models of long- and short-term memory (EPAM/CHREST) has produced a diverse range of applications of perceptual chunking. We focus on recent successes in verbal learning, expert memory, language acquisition and learning multiple representations, to illustrate the implementation and use of chunking mechanisms within contemporary models of human learning. (shrink)

Computational models of learning provide an alternative technique for identifying the number and type of chunks used by a subject in a specific task. Results from applying CHREST to chess expertise support the theoretical framework of Cowan and a limit in visual short-term memory capacity of 3–4 looms. An application to learning from diagrams illustrates different identifiable forms of chunk.

Mental timing studies may be influenced by powerful cognitive illusions that can produce an asymmetry in their rate of progress relative to neuronal timing studies. Both types of timing research are also governed by a temporal asymmetry, expressed by the fact that the direction of causation must follow time's arrow. Here we refresh our earlier suggestion that the temporal asymmetry offers promise as a means of timing mental activities. We update our earlier analysis of Libet's data within this framework. Then (...) we consider the surprises which often occur on those rare occasions when neural timing experiments parallel mental timing work exactly. Together, these surprises and asymmetries prescribe a relentlessly meticulous and fully transparent exposition of timing methods, terms, and concepts which shuns plausible narratives, even when buttressed by rigorous formal models, unless guided by apposite empirical evidence. (shrink)

It is shown that the Maxwell-Lorentz equations can be deduced from the law of Biot-Savart by simply performing some theoretical experimentations.

Individual differences in the strategies that control sequential behavior were investigated in an experiment in which participants memorized sentences and then wrote them by hand, in a non‐cursive style. Thirty‐two participants each wrote eight sentences, which had hierarchical structures with five levels. The dataset included over 31,000 letters. Despite the deliberately constrained nature of the task and stimuli, 23 patterns of behavior were identified from the durations of pauses that occurred before the inscription of letters at four chunk levels, spanning (...) letters, words, phrases, and sentences. A critical path task analytic model, Graphical Production of Memorized Sentences (GPoMS), shows that the control of writing relies on cues that continuously switch between motor actions and chunk retrievals in a just‐in‐time fashion at the level of letter information. GPoMS explains the individual differences in terms of variants of a motor production mechanism and variants of a chunk retrieval mechanism, which involve varying degrees of parallelism between cognitive actions and motor actions. A graphical technique for constructing GPoMS models was developed that enabled the estimation of ongoing working memory demands during production. (shrink)

Education is so strongly emphasized in the Chinese culture that academic success is widely regarded as the only indicator of success, while too much physical activity is often discouraged because it drains energy and affects academic concentration. This study investigated the relations among academic achievement, self?esteem, school conduct and physical activity level. The participants were 333 Chinese pre?adolescents (aged 8?12) in Hong Kong. Examination results and conduct grades were obtained from the school records. Global self?esteem was measured with the Physical (...) self?description questionnaire (PSDQ), while physical activity patterns of the children were assessed with the Physical activity questionnaire for children (PAQ?C). Results showed that high academic achievers consistently attained better school conduct marks. However, physical activity level was quite an independent entity that was related neither to academic achievement nor school conduct. Furthermore, regression analyses showed that only academically high?achieving boys and physically active boys had higher self?esteem. (shrink)

While green innovation has a positive impact on firms’ performance, some established firms that initiate green innovation activities could suffer from insufficient new green knowledge and skills. Since adopting a sustainability orientation helps firms commit to the creation of superior sustainable practices, and efficiently invest resources necessary to develop appropriate new green products, leading to superior green innovation performance, sustainability orientation offers an alternative approach for diversifying green entrants to achieve green innovation success. Building on resource-based, knowledge-based, and capabilities theories, (...) this study aims to identify key factors that enable sustainability orientation of diversifying green entrants and enhance its effect on green innovation performance. As sustainability issues frequently occur upstream at the supplier level, and since supplier involvement effectively determines new product success, this study theorizes that diversifying green entrants that adopt sustainability orientation require two types of green supplier involvement to enhance the effect of sustainability orientation on green innovation performance. Green knowledge-processing capability and green R&D capability complement green supplier involvement as a knowledge source and green supplier involvement as a co-creator, respectively, to further enhance the amount of green innovation performance. Based on a longitudinal dataset of 336 diversifying green entrants, the results support all our hypotheses. Interestingly, an additional analysis suggests that when diversifying green entrants implement green supplier involvement as a co-creator, they achieve greater green innovation performance than those who implement green supplier involvement as a knowledge source. These findings provide important theoretical implications and practical guidance for established firms to pursue green innovation. (shrink)