Lachlan observed that any nonzero d.c.e. degree bounds a nonzero c.e. degree. In this paper, we study the c.e. predecessors of d.c.e. degrees, and prove that given a nonzero d.c.e. degree , there is a c.e. degree below and a high d.c.e. degree such that bounds all the c.e. degrees below . This result gives a unified approach to some seemingly unrelated results. In particular, it has the following two known theorems as corollaries: there is a low c.e. degree isolating (...) a high d.c.e. degree [S. Ishmukhametov, G. Wu, Isolation and the high/low hierarchy, Arch. Math. Logic 41 259–266]; there is a high d.c.e. degree bounding no minimal pairs [C.T. Chong, A. Li, Y. Yang, The existence of high nonbounding degrees in the difference hierarchy, Ann. Pure Appl. Logic 138 31–51]. (shrink)

In this study, for COVID-19, we divide people into four categories: susceptible S t, closely contacted C t, infective I t, and removed R t according to the current epidemic situation and then investigate two models: the SCIR models with immigration and without immigration. For the former, Model 1, we obtain the condition for global stability of its disease-free equilibrium. For the latter, Model 2, we establish the local asymptotic stability of its endemic equilibrium by constructing Lyapunov function. Afterwards, by (...) the bifurcation theory, we qualitatively analyze the properties of its Hopf bifurcations of the latter. Finally, numerical simulations are given to illustrate the obtained results of two models. The results imply the importance of finding closely contacted and overseas imports on epidemic control. It indicates that not only the incubation delay τ is crucial for the containment of the COVID-19 but also the scientific and rigorous containment measures are the key factors of the success of the containment. (shrink)

We prove that for any computably enumerable degree c, if it is cappable in the computably enumerable degrees, then there is a d.c.e. degree d such that c d = 0′ and c ∩ d = 0. Consequently, a computably enumerable degree is cappable if and only if it can be complemented by a nonzero d.c.e. degree. This gives a new characterization of the cappable degrees.

From the beginning of human, human’s thinking about the nature object begun refers to the root basis of everything, the people in all the parts of the world, from the far far old time, begun their thinking. In old Greece, there are theory or understanding about the Onto produced by many famous person with big name such as THALES, ANAKSIMANDROS, PUTHAGORAS, HERAKLEITOS. By Herakleitos, the understanding of the onto in Greece got a very good step. While in China, almost at (...) the same age as Herakleitos, China’s understanding about the onto, was standing at almost equivalent level with that in Greece. In China, this theory is called “Yin-Yang, Wu Hang”. “Yin-Yang” means the contrast mentioned by Herakleitos, the movement of the “Wu Hang" means the logic mentioned by Herakleitos. So, by time of Herakleitos, (about 5th. Century B.C.) Greece and China got almost same understanding level about the Onto. but, they are also different. China’s is the way of describe, imagery, while the greece’s is the explain and demonstrate by thinking, by logic. The way of imagery go around without development, but the way of logic could go on for the development. So, in China, theory of Onto stay at the imagery explain, in Greece and Europe latter, theory of Onto continue develop, gave birth to the Cognition, Science. (shrink)

Cholak, Groszek and Slaman proved in J Symb Log 66:881–901, 2001 that there is a nonzero computably enumerable (c.e.) degree cupping every low c.e. degree to a low c.e. degree. In the same paper, they pointed out that every nonzero c.e. degree can cup a low2 c.e. degree to a nonlow2 degree. In Jockusch et al. (Trans Am Math Soc 356:2557–2568, 2004) improved the latter result by showing that every nonzero c.e. degree c is cuppable to a high c.e. degree (...) by a low2 c.e. degree b. It is natural to ask in which subclass of low2 c.e. degrees can b in Jockusch et al. (Trans Am Math Soc 356:2557–2568, 2004) be located. Wu proved in Math Log Quart 50:189–201, 2004 that b can be cappable. We prove in this paper that b in Jockusch, Li and Yang’s result can be noncuppable, improving both Jockusch, Li and Yang, and Wu’s results. (shrink)

We say that a computably enumerable (c. e.) degree a is plus-cupping, if for every c.e. degree x with $0 < x \leq a$ , there is a c. e. degree $y \not= 0'$ such that $x \vee y = 0/\'$ . We say that a is n-plus-cupping. if for every c. e. degree x, if $0 < x \leq a$ , then there is a $low_n$ c. e. degree 1 such that $x \vee l = 0'$ . Let PC (...) and $PC_n$ be the set of all plus-cupping, and n-plus-cupping c. e. degrees respectively. Then $PC_{1} \subseteq PC_{2} \subseteq PC_3 = PC$ . In this paper we show that $PC_{1} \subset PC_2$ , so giving a nontrivial hierarchy for the plus cupping degrees. The theorem also extends the result of Li, Wu and Zhang [14] showing that $LC_{1} \subset LC_2$ , as well as extending the Harrington plus-cupping theorem [8]. (shrink)

We show that there is a cuppable c.e. degree, all of whose cupping partners are high. In particular, not all cuppable degrees are${\operatorname {\mathrm {low}}}_3$-cuppable, or indeed${\operatorname {\mathrm {low}}}_n$cuppable for anyn, refuting a conjecture by Li. On the other hand, we show that one cannot improve highness to superhighness. We also show that the${\operatorname {\mathrm {low}}}_2$-cuppable degrees coincide with the array computable-cuppable degrees, giving a full understanding of the latter class.

We derive, in path integral approach, the (anomalous) master Ward identity associated with an infinite set of nonlocal conservation laws in two-dimensional principal chiral models.

The principal–principal perspective suggests that controlling shareholders have excessive influence on corporate philanthropy and may direct corporate funds to charitable causes to support their personal interests. Analysis of a sample of Chinese private firms listed on the Shenzhen or Shanghai stock exchange between 2004 and 2011 shows that there is a significant and negative relationship between corporate giving and the share held by the largest shareholders, suggesting that controlling shareholders are opportunistic in directing corporate charitable contributions; there is a significant (...) and positive relationship between corporate giving and the political connections of the largest shareholders and their agents, suggesting compatibility between corporate contributions and the personal interests of the controlling shareholders; there is a stronger negative relationship between corporate giving and the share of the company held by the largest shareholders in politically connected firms, suggesting that political connections contribute to increased opportunistic corporate giving. Overall, our study provides important evidence for the “one dominant controlling shareholder” phenomenon by testing and extending the principal–principal framework and showing that the largest shareholders of Chinese firms appear to donate to charitable causes that ultimately serve their personal interests at the expense of minority shareholders. (shrink)

Under the dual background of underemployment and health inequality, this study empirically analyzes the impact of education level on underemployed workers’ health based on data from the 2016 China Labor-force Dynamics Survey. The results show that underemployment is significantly related to the decline of self-rated health, increased depressive tendencies, and the prevalence of illness over a certain period. The results indicate that underemployment can significantly reduce the health level of workers in both low and high education level groups. However, underemployment (...) appears to have no significant impact on workers’ health in the middle education level group. This result holds even if the measurement method of the indicators is adjusted and endogeneity is considered; this indicates that the research conclusions are robust. Moreover, this kind of health inequality mainly comes from the economic and leisure effects of underemployment for workers with different educational levels. Although underemployment significantly reduces the economic level of workers in each education level group, it brings a positive leisure effect to workers with a middle education level and a negative leisure effect to workers with a low education level. This study provides empirical support for increasing labor protection mechanisms for underemployed people and reducing the health inequality caused by differences in education level. (shrink)

: Filial piety is a core value in ancient Chinese culture, and it still exerts significant influence on the attitudes, behavior and daily life of Chinese people today. At present, China is facing an increasingly aging population and the concern how to properly care for the elderly. Through the vertical review of filial piety in China’s history, two constant elements, namely support and respect, stands out among China’s traditions. There is an argument that addressing the contemporary elderly care problem requires (...) the adequate support from two perspectives, material support from families and societies for the aged and spiritual caring for them. It is further argued that any approaches aimed at addressing contemporary elderly care issue should take into consideration the actual social and culture conditions in China, including the cultural traditions of filial piety. Resumo: A piedade filial era um valor central na cultura chinesa antiga, e ainda exerce influência significativa nas atitudes, comportamento e vida cotidiana do povo chinês. Atualmente, a China está enfrentando uma população cada vez mais envelhecida e as preocupações associadas a como cuidar adequadamente dos idosos do país. Através da revisão vertical da piedade filial, ao longo da história da China, para este trabalho, dois elementos constantes emergiram nas tradições, a saber, apoio e respeito. Argumenta-se que a abordagem do problema contemporâneo do cuidado ao idoso exigirá a incorporação adequada de ambas as dimensões, ou seja, fornecer não apenas apoio material ao idoso, na família e na sociedade, mas também prover seu cuidado espiritual. Argumenta-se ainda que quaisquer abordagens destinadas a tratar da questão devem ser baseadas nas condições sociais e culturais reais, na China, incluindo e passando além das tradições culturais de piedade filial. (shrink)

The problem of rationalizing denominators for two types of fractions is discussed in the paper. By using the theory and algorithms of Gröbner bases, we first introduce a method to rationalize the denominators of fractions with square root and cube root, and then, for the denominators with higher radical of the general form, the problem of rationalizing denominators is converted into the related problem of finding the minimal polynomials. Some interesting results and an executable algorithm for rationalizing the denominator of (...) these type fractions are presented. Furthermore, an example is also established to illustrate the effectiveness of the algorithm. (shrink)

This study conducts a bibliometric analysis of news discourse analysis using CiteSpace to sketch its scientific landscape based on journal articles in English in the Scopus database from 1988 through 2020. The statistical analysis provides evidence for the interdisciplinarity of this area, and shows an upward trend in general over these years as well as an accelerating growth rate in the past decade. Findings also indicate that the problem-oriented CDA has gained the most popularity in this area since its emergence, (...) and the appraisal framework, multimodality analysis, and discursive news values have become three hotspots of news discourse analysis. In addition, the authors in the West have contributed most in this area, but those from Chinese Mainland, Malaysia, South Africa, and Indonesia have gradually been an emerging powerhouse, which has added diversity in topics and will enhance equality and promote dialogue between different communities, ethnics, and races across the globe. (shrink)

This study provides an attributional perspective to the ethical leadership literature by examining the role of attributed altruistic motives and perceptions of organizational politics in a moderated mediation model. Path analytic tests from two field studies were used for analyses. The results support our hypotheses that attributed altruistic motives would mediate the relationship between perceived ethical leadership and affective organizational commitment. Moreover, the relationship between perceived ethical leadership and attributed altruistic motives was stronger when perceptions of organizational politics were high (...) but weaker when these perceptions were low. The study concludes with a discussion of future research implications as well as managerial implications. (shrink)

Frequent occurrences of academic misconduct have become a significant obstacle to scientific progress, necessitating collaborative governance from multiple stakeholders to achieve effective mitigation. However, as pivotal institution in national innovation and the governance of academic misconduct, universities often neglect the issue of academic misconduct in promoting innovation. To elucidate the potential damage that neglecting research integrity governance may inflict on university innovation, this study utilized retraction and innovation data from Chinese Double First-Class Initiative universities between 2007 and 2017 to systematically (...) explore the impact, mechanism, and economic consequences of academic misconduct exposure on university innovation output. Our findings indicate that exposure to academic misconduct significantly reduces the innovation output levels of the involved universities, with research reputation being the primary mechanism driving this effect. The economic consequence analysis reveals that innovation stakeholders strategically adjust their behavior based on the research integrity status of universities. Such adjustments lead to a shift in research funding and innovation collaboration structures in a manner detrimental to long-term innovation, thereby causing economic losses to the universities’ innovation. Moreover, the negative impact of academic misconduct on university innovation output is more pronounced in STEM disciplines, comprehensive universities, and high-impact journal exposure events, and it intensifies with the prolongation of exposure lag time. Overall, this study enriches the theoretical framework of factors influencing university innovation output, clearly identifying the crucial role of research reputation in promoting university innovation. It provides theoretical basis and practical impetus for universities to proactively strengthen research integrity governance. (shrink)

The current study mainly explored the influence of fluid intelligence and emotional intelligence on affective decision-making from a developmental perspective, specifically, during the transition from childhood into early adolescence. Meanwhile, their age-related differences in affective decision-making were explored. A total of 198 participants aged 8–12 completed the Iowa Gambling Task, the Cattell’s Culture Fair Intelligence Test and the Trait Emotional Intelligence Questionnaire-Child Form. Based on the net scores of IGT, the development of affective decision-making ability did not increase monotonically with (...) age, and there was a developmental trend of an impaired IGT performance in early adolescence, especially in the early learning phase of the IGT. More importantly, IQ and EI played different roles for children and early adolescents: IQ and EI jointly predicted the IGT performance for 8–10 years old children, whereas only EI contributed to the IGT performance of 11–12 years old early adolescents. The present study extends the evidence how cognitive processing and emotional processing interact in affective decision-making from the developmental perspective. Furthermore, it provides insights of future research and intervention with early adolescents’ poor affective decision-making. (shrink)

This study aims to examine the neural correlates of cognitive shifting during the Dimensional Change Card Sort Task task with functional near-infrared spectroscopy. Altogether 49 children completed the DCCS tasks, and 25 children passing all items were classified into the Switch group. Twenty children committing more than one perseverative errors were grouped into the Perseverate group. The Switch group had Brodmann Area 9 and 10 activated in the pre-switch period and BA 6, 9, 10, 40, and 44 in the post-switch (...) period. In contrast, the Perseverate group had BA 9 and 10 activated in the pre-switch period and BA 8, 9, 10 in the post-switch period. The general linear model results afford strong support to the “V-shape curve” hypothesis by identifying a significant decrease–increase cycle in BA 9 and 44, the neural correlations of cognitive shifting. (shrink)

Lung nodules are an early symptom of lung cancer. The earlier they are found, the more beneficial it is for treatment. However, in practice, Chinese doctors are likely to cause misdiagnosis. Therefore, deep learning is introduced, an improved target detection network is used, and public datasets are used to diagnose and identify lung nodules. This paper selects the Mask-RCNN network and uses the dense block structure of Densenet and the channel shuffle convolution method to improve the Mask-RCNN network. The experimental (...) results prove that proposed algorithm is extremely effective. (shrink)

Based on the perspective of the regional innovation system, this study constructs an analytical framework for the influence of government R&D funding on regional innovation quality and uses 283 Chinese cities as research samples to empirically test the influence of government R&D funding methods such as subsidies and tax preferences on regional innovation quality by the spatial Durbin model. According to the study, China’s regional innovation quality has a positive spatial correlation. Subsidies can improve regional innovation quality, which is mainly (...) realized by increasing the input of innovation resources from local direct innovation subjects, attracting the inflow of innovation resources from neighboring areas, and increasing the innovation support from local indirect innovation subjects. Besides, spatial competition for subsidies makes it beneficial to improve the regional innovation quality in neighboring regions, while the promotion effect of tax preferences is not significant. When considering the heterogeneity of the city location and administrative hierarchy, it shows that the government R&D funding cannot improve the innovation quality of the Eastern cities and higher-administrative-hierarchy cities, while it can improve that of the Middle and Western cities and general-administrative-hierarchy cities. Furthermore, government R&D funding widens the gap of regional innovation quality, which may be related to the existing “insufficient intervention” and “excessive intervention” of government R&D funding. This study provides insights into the implementation of R&D funding by the government to promote the development of regional innovation quality. (shrink)

COVID-19 has affected every aspect of our life, including economic, social, and academic. Exchange and mobility students face more difficulties overseas, and Chinese students are no exception. However, e-learning has been introduced by institutions in many countries. The present study examines the psychosocial factors affecting the academic performance of Chinese outbound exchange and mobility students during the COVID-19 pandemic. The study surveys about 186 Chinese outbound exchange and mobility students. The present study performs the quantitative data analysis using Partial Least (...) Square Structural Equation Modeling through the Smart PLS software version 3. By confirming the measurement model and structural model assessments, the study finds that personality, social support, and language fluency are psychosocial factors that significantly influence the exchange and mobility students’ academic performance. This study contributes by establishing relationships among psychosocial factors, language fluency and academic performance. Besides, practitioners can be benefitted by understanding students’ psychosocial factors and its relation to academic performance during COVID-19 pandemic. (shrink)

Interval time-varying delay is common in control process, e.g., automatic robot control system, and its stability analysis is of great significance to ensure the reliable control of industrial processes. In order to improve the conservation of the existing robust stability analysis method, this paper considers a class of linear systems with norm-bounded uncertainty and interval time-varying delay as the research object. Less conservative robust stability criterion is put forward based on augmented Lyapunov-Krasovskii functional method and reciprocally convex combination. Firstly, the (...) delay interval is partitioned into multiple equidistant subintervals, and a new Lyapunov-Krasovskii functional comprising quadruple-integral term is introduced for each subinterval. Secondly, a novel delay-dependent stability criterion in terms of linear matrix inequalities is given by less conservative Wirtinger-based integral inequality approach. Three numerical comparative examples are given to verify the superiority of the proposed approach in reducing the conservation of conclusion. For the first example about closed-loop control systems with interval time-varying delays, the proposed robust stability criterion could get MADB about 0.3 more than the best results in the previous literature; and, for two other uncertain systems with interval time-varying delays, the MADB results obtained by the proposed method are better than those in the previous literature by about 0.045 and 0.054, respectively. All the example results obtained in this paper clearly show that our approach is better than other existing methods. (shrink)

With rapid changes in technology, knowledge innovation has become more and more complex. Complex partners facilitate knowledge creation and innovation in complex problem-solving. Relying on R&D cooperation with forerunners, latecomers can acquire new knowledge factors and new ideas and use them to create new knowledge. This study demonstrated the knowledge innovation mechanism based on linkages between periphery knowledge and core knowledge with knowledge map theory and set methodology. A case of R&D cooperation between latecomers and forerunners was introduced to verify (...) this mechanism. The results show that latecomers could share forerunners’ periphery knowledge in R&D cooperation through formal and informal interaction and acquire the core knowledge factors in periphery knowledge based on the linkages between them. With these core knowledge factors, latecomers integrate them into their internal knowledge system and create new knowledge. By analyzing the linkages between periphery and core knowledge factors, this study creatively demonstrates the knowledge innovation mechanism in knowledge linkage perspective. It deepens the understanding of R&D cooperation between latecomers and forerunners and expands the focus of knowledge innovation theory. This study provides a new insight into latecomers effectively activating internal and external knowledge resources through R&D cooperation. (shrink)

Attention has been theorized as a system comprising three networks that can be estimated reliably by the attention network test ; the three networks are defined as alerting, orienting, and conflict control. The present study aims to identify the attention networks that are crucial for elite shooting and archery athletes and to examine whether mindfulness training can improve elite athletes' attention networks. We compared the performances in ANT between 62 elite athletes from the Chinese national team of shooting and archery (...) and 49 athletes from a provincial team in China. The results indicate three well-functioned attention networks in both groups, but elite athletes in the national team responded faster overall than athletes in the provincial team. The 62 elite athletes in the national team then received mindfulness training with varied periods ranging from 5 to 8 weeks, after which the ANT was re-administered. After mindfulness training, the elite athletes improved in orienting and conflict control networks compared with their pre-training performances. These results suggest that elite shooting and archery athletes in the national team are more efficient in all three attention networks, which means that they are able to reach the alerting state faster, make better use of environmental information, and suppress interference from distractors more efficiently. Moreover, the orienting and conflict control networks of the elite shooting and archery athletes can be improved by mindfulness training. We conclude that mindfulness practice should be considered as a useful addition to daily training for shooting and archery athletes. (shrink)

PurposeThe aim of this study was to investigate and compare impulsiveness, negative emotion, cognitive function, and P300 components among gamma-hydroxybutyrate -addicted patients, heroin-dependent patients, and methadone maintenance treatment subjects.MethodsA total of 48 men including 17 GHB addicts, 16 heroin addicts, 15 MMT subjects, and 15 male mentally healthy controls were recruited. All subjects were evaluated for symptoms of depression, anxiety, impulsiveness, and cognitive function through the Patient Health Questionnaire, the Generalized Anxiety Disorder 7-item, the Barratt Impulsiveness Scale version II, the (...) Beijing version of the Montreal Cognitive Assessment, the behavioral test, and event-related potential P300 detection.Results The mean scores of BIS-II in the GHB addiction group, heroin dependence group, and MMT group were significantly higher than those of the HC group. The total scores of BJ-MOCA in GHB addiction group was the worst among the four groups, followed by heroin addiction, MMT group and HC group. The response time in the GHB addiction group was the longest among the four groups, followed by the heroin addiction, MMT, and HC groups. The amplitude and latency of P300 in GHB addiction subjects were significantly lower and longer than those of the MMT group and the HC group. For the three types of addiction, the P300 amplitudes at Fz, Cz, Pz, T5, and T6 were negatively correlated with the scores of GAD-7, PHQ-9, and BIS-II; the P300 latencies were positively correlated with the response time and negatively correlated with the scores of the BJ-MoCA.ConclusionPeople with an addiction were likely to have increased impulsiveness. The cognitive function of the GHB and heroin-addicted subjects, including the heroin detoxification and the MMT groups, was severely impaired, especially for the GHB-addicted patients. The impairment manifested as abnormalities of BJ-MoCA, response time, and P300 components. (shrink)

This study aimed to analyze the relations between class competition and primary school students’ academic achievement, considering the possible mediating roles of learning anxiety and learning engagement. Participants were 1,479 primary school students from four primary schools in Zhejiang, China. We analyzed participants’ scores for class competition, learning anxiety, and learning engagement and their last two final exam scores. Class competition did not directly predict academic achievement, but indirectly affected academic achievement through learning anxiety and learning engagement. There were three (...) effect paths: class competition negatively predicted academic achievement by increasing learning anxiety; class competition positively predicted academic achievement by promoting learning engagement; and class competition affected academic achievement through multiple mediating effects of learning anxiety and learning engagement. This study highlights the important roles of learning anxiety and learning engagement in class competition and academic achievement, which have theoretical and practical significance. (shrink)