Xi Chen

Copyright © 2016 is held by owner/author.In this paper we present optimizations that use DVFS mechanisms to reduce the total energy usage in scientific applications. Our main insight is that noise is intrinsic to large scale parallel executions and it appears whenever shared resources are contended. The presence of noise allows us to identify and manipulate any program regions amenable to DVFS. When compared to previous energy optimizations that make per core decisions using predictions of the running time, our scheme uses a qualitative approach to recognize the signature of executions amenable to DVFS. By recognizing the "shape of variability" we can optimize codes with highly dynamic behavior, which pose challenges to all existing DVFS techniques. We validate our approach using offline and online analyses for one-sided and two-sided communication paradigms. We have applied our methods to NWChem, and we show best case improvements in energy use of 12% at no loss in performance when using online optimizations running on 720 Haswell cores with one-sided communication. With NWChem on MPI two-sided and offline analysis, capturing the initialization, we find energy savings of up to 20%, with less than 1% performance cost.

Knowledge of three-dimensional structures of each individual particles of asymmetric and flexible proteins is essential in understanding those proteins' functions; but their structures are difficult to determine. Electron tomography provides a tool for imaging a single and unique biological object from a series of tilted angles, but it is challenging to image a single protein for three-dimensional reconstruction due to the imperfect mechanical control capability of the specimen goniometer under both a medium to high magnification and an optimized beam coherence condition. Here, we report a fully mechanical control method for automating ET data acquisition without using beam tilt/shift processes. This method could reduce the accumulation of beam tilt/shift that used to compensate the error from the mechanical control, but downgraded the beam coherence. Our method was developed by minimizing the error of the target object center during the tilting process through a closed-loop proportional-integral control algorithm. The validations by both negative staining and cryo-electron microscopy suggest that this method has a comparable capability to other ET methods in tracking target proteins while maintaining optimized beam coherence conditions for imaging.

The Yr5 gene confers resistance to all races of the wheat stripe rust pathogen [Puccinia striiformis Westend. f. sp. tritici Eriks. ] identified so far in the USA. Cosegregating resistance gene analog polymorphism markers for Yr5 are available but their use requires skills in polyacrylamide gel electrophoresis and may not be polymorphic across various varieties. To develop better markers to be used in marker-assisted selection for the Yr5 resistance, sequence tagged site primers were designed on the basis of the sequences of RGAP markers Xwgp-18 from the spring wheat 'Avocet Susceptible' and Xwgp-17 from the Yr5 near isogenic line in the AVS background carrying the Yr5 gene from T. aestivum subsp. spelta Thell. cv. Album. Three sets of STS markers were developed to amplify a region including a polymorphic 6-base pairs insertion-deletion. The cosegregation of the STS markers with Yr5 was confirmed with 114 BC 7:F3 lines developed from the cross between AVS and TSA. The STS markers worked well in five out of 17 non-Yr5 wheat varieties, but the remaining varieties had a similar size of fragment to the Yr5 marker. Because the codominant STS markers were based on a 6-bp indel, they could not be separated by agarose gel electrophoresis. Cleaved amplified polymorphic sequence markers were then developed on the basis of a DpnII restriction site that is present in all non-Yr5 varieties and absent in the Yr5 NIL. The CAPS markers for the Yr5 NIL and non-Yr5 varieties can be separated by agarose gel electrophoresis. The codominant STS markers are easier to score than the original RGAP markers. The CAPS markers are not only easier to score, but also can be used in crosses of an Yr5 donor with a much wider range of wheat germplasms. These markers should be valuable tools to accelerate the introgression of Yr5 into commercial cultivars and to combine Yr5 with other genes for durable resistance to stripe rust.

© 2015 Macmillan Publishers Limited All rights reserved. Genome-wide gene expression measurements have enabled comprehensive studies that integrate the changes of gene expression and phenotypic information to uncover their novel associations. Here we reported the association analysis between psychophysical phenotypes and genome-wide gene expression changes in human adaptation to one of the most extreme climates on Earth, the Antarctic Dome Argus. Dome A is the highest ice feature in Antarctica, and may be the coldest, driest and windiest location on earth. It is considered unapproachable due to its hostile environment. In 2007, a Chinese team of 17 male explorers made the expedition to Dome A for scientific investigation. Overall, 133 psychophysical phenotypes were recorded, and genome-wide gene expression profiles from the blood samples of the explorers were measured before their departure and upon their arrival at Dome A. We found that mood disturbances, including tension, depression, anger and fatigue, had a strong, positive, linear relationship with the level of a male sex hormone, testosterone, using the Pearson correlation coefficient analysis. We also demonstrated that significantly lowest-level Gene Ontology groups in changes of gene expression in blood cells with erythrocyte removal were consistent with the adaptation of the psychophysical characteristics. Interestingly, we discovered a list of genes that were strongly related to significant phenotypes using phenotype and gene expression PCC analysis. Importantly, among the 70 genes that were identified, most were significantly related to mood disturbances, where 42 genes have been reported in the literature mining, suggesting that the other 28 genes were likely novel genes involved in the mood disturbance mechanism. Taken together, our association analysis provides a reliable method to uncover novel genes and mechanisms related to phenotypes, although further studies are needed.

© 2014 Li et al. Aedes albopictus is a very invasive and aggressive insect vector that causes outbreaks of dengue fever, chikungunya disease, and yellow fever in many countries. Vector ecology and disease epidemiology are strongly affected by environmental changes. Urbanization is a worldwide trend and is one of the most ecologically modifying phenomena. The purpose of this study is to determine how environmental changes due to urbanization affect the ecology of Aedes albopictus. Aquatic habitats and Aedes albopictus larval population surveys were conducted from May to November 2013 in three areas representing rural, suburban, and urban settings in Guangzhou, China. Ae. albopictus adults were collected monthly using BG-Sentinel traps. Ae. albopictus larva and adult life-table experiments were conducted with 20 replicates in each of the three study areas. The urban area had the highest and the rural area had the lowest number of aquatic habitats that tested positive for Ae. albopictus larvae. Densities in the larval stages varied among the areas, but the urban area had almost two-fold higher densities in pupae and three-fold higher in adult populations compared with the suburban and rural areas. Larvae developed faster and the adult emergence rate was higher in the urban area than in suburban and rural areas. The survival time of adult mosquitoes was also longer in the urban area than it was in suburban and rural areas. Study regions, surface area, water depth, water clearance, surface type, and canopy coverage were important factors associated with the presence of Ae. albopictus larvae. Urbanization substantially increased the density, larval development rate, and adult survival time of Ae. albopictus, which in turn potentially increased the vector capacity, and therefore, disease transmissibility. Mosquito ecology and its correlation with dengue virus transmission should be compared in different environmental settings.

Recently implemented Chinese health insurance schemes have failed to achieve a Chinese health care system that is family-oriented, family-based, family-friendly, or even financially sustainable. With this diagnosis in hand, the authors argue that a financially and morally sustainable Chinese health care system should have as its core family health savings accounts supplemented by appropriate health insurance plans. This essay’s arguments are set in the context of Confucian moral commitments that still shape the background culture of contemporary China

The apolipoprotein E gene plays an important role in the pathogenesis of Alzheimer's disease , and amyloid plaque comprised mostly of the amyloid-beta peptide ) is one of the major hallmarks of AD. However, the relationship between these two important molecules is poorly understood. We examined how A treatment affects APOE expression in cultured cells and tested the role of the transcription factor NF-B in APOE gene regulation. To delineate NF-B's role, we have characterized a 1098 nucleotide segment containing the 5'-flanking region of the human APOE gene . Sequence analysis of this region suggests the presence of two potential NF-B elements. To demonstrate promoter activity, the region was cloned upstream of a promoterless luciferase gene. This segment was able to drive expression of luciferase in transient transfections of human fetal glial cells. Promoter activity was stimulated twofold by A treatment. Pretreatment with double-stranded DNA decoy oligonucleotides against NF-B reduced A stimulation. Deletion and mutagenetic analyses demonstrated that the distal NF-B element was functional and showed a strong DNA-protein complex band in gel shift analysis, similar to that from control NF-B consensus element. An anti-inflammatory and anti-NF-B drug, sodium salicylate, significantly blocked A-induced APOE promoter function. Our data provide evidence that upregulation of APOE by A in astroglial cells is mediated by an NF-B-element present in the 5'-flanking region of the APOE gene

Background eHealth was widely used during the COVID-19 pandemic. Much attention was given to the technical aspects of eHealth, such as infrastructure and cost, while the soft skill of compassion remained underexplored. The wide belief in compassionate care is more compatible with in-person interactions but difficult to deliver via e-platforms where personal and environmental clues were lacking urges studying this topic. Purpose to explore the experience of delivering compassionate care via an eHealth platform among healthcare professionals working to contain the COVID-19 pandemic. Methods A qualitative study design with an interpretative phenomenological analysis approach was used. Twenty healthcare professionals (fifteen nurses and five physicians) who provided care using technology platforms, such as telephone hotlines, mobile apps, and social media, were interviewed individually. Ethical considerations Permission to conduct the study was obtained from the Institutional Review Board. Results Participants stated that “eHealth enabled compassionate care during the pandemic” by ensuring patient care availability and accessibility. They shared experiences of “communicating compassionate care via eHealth” with suggestions of addressing patients’ needs with empathy, adopting a structured protocol to guide eHealth communication, and using more advanced visual-media methods to promote human-to-human interaction. They recommended “setting realistic mutual expectations” considering the limitations of eHealth in handling complex health situations and staffing shortages. Participants considered “low eHealth literacy hinders compassion.” Additionally, they recommended the need for “institutional/system-level support to foster compassionate care.” Conclusion Participants recognized the importance of integrating compassion into eHealth services. Promotion of compassionate care requires standardization of eHealth services with institutional and system-level support. This also includes preparing adequate staffing who can communicate compassionate care via eHealth, set realistic expectation, and adjust communication to eHealth literacy level while meeting the needs of their patients.

Background Nurses frequently experience ethical issues in their area of practice. In the challenging reality of today’s healthcare environment, nursing students need to be prepared to deal with ethical issues in their future roles. Nevertheless, Chinese nursing students’ ethical sensitivity status and the factors influencing it have not been described. Objective This study aims to explore the level of ethical sensitivity and its influencing factors among Chinese nursing students. Research design This was a cross-sectional study. We firstly cross-culturally adapted the Japanese version of the Ethical Sensitivity Questionnaire for Nursing Students (ESQ-NS) into a Chinese version. Then, we administered the Chinese version of ESQ-NS, the Caring Ability Inventory (CAI), and general information questionnaire to nursing undergraduates. Participants and research context The invitations were sent to 600 nursing undergraduates from four universities in Hunan, China. Ethical considerations The study was supported by the Institutional Review Board (IRB) of the lead university. The Approval No. was E202092. Results A total of 489 undergraduate nursing students participated in the study. The mean score for ethical sensitivity of the samples was 36.34 ± 4.90, and 187.99 ± 22.64 for their humanistic care ability. Pearson’s correlation coefficient test indicated a meaningful and positive relationship between the ethical sensitivity and humanistic care ability (r = 0.576 and p

In this paper, we propose a method to design the pseudorandom number generator using three kinds of four-wing memristive hyperchaotic systems with different dimensions as multientropy sources. The principle of this method is to obtain pseudorandom numbers with good randomness by coupling XOR operation on the three kinds of FWMHSs with different dimensions. In order to prove its potential application in secure communication, the security of PRNG based on this scheme is analyzed from the perspective of cryptography. In addition, PRNG has passed the NIST 800.22 and ENT test, which shows that PRNG has good statistical characteristics. Finally, an image encryption algorithm based on PRNG is adopted. In the encryption algorithm, the optimized Arnold matrix scrambling method and the diffusion processing based on XOR are used to obtain the final encrypted image. Through the evaluation of encryption performance, it is concluded that there is no direct relationship between the pristine image and encrypted image. The results show that the proposed image encryption scheme has good statistical output characteristics and security performance in line with cryptography.

This essay illustrates what the Chinese family-based and harmony-oriented model of medical decision making is like as well as how it differs from the modern Western individual-based and autonomy-oriented model in health care practice. The essay discloses the roots of the Chinese model in the Confucian account of the family and the Confucian view of harmony. By responding to a series of questions posed to the Chinese model by modern Western scholars in terms of the basic individualist concerns and values embedded in the modern Western model, we conclude that the Chinese people have justifiable reasons to continue to apply the Chinese model to their contemporary health care and medical practice

The reach-avoid game theory is an ideal tool to handle the conflicts among intelligent agents and has been previously studied assuming full state information and no time limits on the players in the past decades. In this article, we extend the problem by requiring the defender to detect the attacker and adding maximum operation time constraints to the attacker. The attacker aims to reach the target region without being captured or reaching its time limit. The defender can employ strategies to intercept the attacker only when the attacker is detected. A geometric method is proposed to solve this game qualitatively. By analyzing the geometric property of the Apollonian circle and the detection range, we give the barrier under the condition that the attacker is initially detected and the attacker’s shortest route which guarantees its arrival at the target region when it is initially outside the detection range. Then, a barrier that separates the game space into two respective winning regions of the players is constructed based on the shortest route and the time limit of the attacker. The main contributions of this work are that this paper provides the first attempt to introduce the abovementioned two concepts simultaneously, which makes the game more practical, and we provide the complete solution of the game in all possible situations.

This paper constructs a predictive model of student reading literacy based on data from students who participated in the Program for International Student Assessment from four provinces/municipalities of China, i.e., Beijing, Shanghai, Jiangsu and Zhejiang. We calculated the contribution of influencing factors in the model by using eXtreme Gradient Boosting algorithm and sHapley additive exPlanations values, and get the following findings: Factors that have the greatest impact on students’ reading literacy are from individual and family levels, with school-level factors taking a relative back seat. The most important influencing factors at individual level are reading metacognition and reading interest. The most important factors at family level are ESCS and language environment, and dialect is negative for reading literacy, whereas proficiency in both a dialect and Mandarin plays a positive role. At the school level, the most important factors are time dedicated to learning and class discipline, and we found that there is an optimal value for learning time, which suggests that reasonable learning time is beneficial, but overextended learning time may make academic performance worse instead of improving it.

Registration of a series of the two-dimensional electron microscope images of the brain tissue into volumetric form is an important technique that can be used for neuronal circuit reconstruction. However, complex appearance changes of neuronal morphology in adjacent sections bring difficulty in finding correct correspondences, making serial section neural image registration challenging. To solve this problem, we consider whether there are such stable "markers" in the neural images to alleviate registration difficulty. In this paper, we employ the spherical deformation model to simulate the local neuron structure and analyze the relationship between registration accuracy and neuronal structure shapes in two adjacent sections. The relevant analysis proves that regular circular structures in the section images are instrumental in seeking robust corresponding relationships. Then, we design a new serial section image registration framework driven by this neuronal morphological model, fully utilizing the characteristics of the anatomical structure of nerve tissue and obtaining more reasonable corresponding relationships. Specifically, we leverage a deep membrane segmentation network and neural morphological physical selection model to select the stable rounded regions in neural images. Then, we combine feature extraction and global optimization of correspondence position to obtain the deformation field of multiple images. Experiments on real and synthetic serial EM section neural image datasets have demonstrated that our proposed method could achieve more reasonable and reliable registration results, outperforming the state-of-the-art approaches in qualitative and quantitative analysis.

Previous studies have found the effect of cognitive skills on reading ability, but the role of different reading-related skills in acquisition of Chinese as a second/foreign language remains unexplored. Prior meta-analyses on the relationship between cognitive skills and reading have been conducted primarily in native English-speaking or Mandarin-speaking children. The purpose of the present meta-analysis was to examine the relationship between Chinese reading-related skills and Chinese word reading of CSL/CFL learners. A search of English and Chinese databases yielded 42 effect sizes, comprising 1103 subjects met the criteria for meta-analysis and were included in the final meta-analysis. Results revealed a moderate relationship between phonological awareness, morphological awareness, orthographic awareness, rapid automatized naming and Chinese word reading in CSL/CFL learners. In addition, a moderating effect of length of study on the relationship between phonological awareness and Chinese word reading : phonological awareness and Chinese word reading correlated more strongly for beginning learners than for advanced learners. These results suggest importance of cognitive factors in the acquisition of Chinese word reading as a second language. Results also shed light on the impact of length of study on the influence from phonological awareness to the sensitive period of phonological learning for CSL/CFL learners.

The Toulmin model has been proved useful in law and argumentation theory. This model describes the basic process in justifying a claim, which comprises six elements, i.e., claim (C), data (D), warrant (W), backing (B), qualifier (Q), and rebuttal (R). Specifically, in justifying a claim, one must put forward ‘data’ and a ‘warrant’, whereas the latter is authorized by ‘backing’. The force of the ‘claim’ being justified is represented by the ‘qualifier’, and the condition under which the claim cannot be justified is represented as the ‘rebuttal’. To further improve the model, (Goodnight, Informal Logic 15:41–52, 1993) points out that the selection of a backing needs justification, which he calls legitimation justification. However, how such justification is constituted has not yet been clarified. To identify legitimation justification, we separate it into two parts. One justifies a backing’s eligibility (legitimation justification 1 ; LJ 1 ); the other justifies its superiority over other eligible backings (legitimation justification 2 ; LJ 2 ). In this paper, we focus on LJ 1 and apply it to the legal justification (of judgements) in hard cases for illustration purposes. We submit that LJ 1 refers to the justification of the legal interpretation of a norm by its backing, which can be further separated into several orderable subjustifications. Taking the subjustification of a norm’s existence as an example, we show how it would be influenced by different positions in the philosophy of law. Taking the position of the theory of natural law, such subjustification is presented and evaluated. This paper aims not only to inform ongoing theoretical efforts to apply the Toulmin model in the legal field, but it also seeks to clarify the process in the justification of legal judgments in hard cases. It also offers background information for the possible construction of related AI systems. In our future work, LJ 2 and other subjustifications of LJ 1 will be discussed.

The outbreak of COVID-19 is a public health crisis that has had a profound impact on society. Stigma is a common phenomenon in the prevalence and spread of infectious diseases. In the crisis caused by the pandemic, widespread public stigma has influenced social groups. This study explores the negative emotions arousal effect from online public stigmatization during the COVID-19 pandemic and the impact on social cooperation. We constructed a model based on the literature and tested it on a sample of 313 participants from the group being stigmatized. The results demonstrate: (1) relevance and stigma perception promote negative emotions, including anxiety, anger, and grief; (2) the arousal of anger and grief leads to a rise in the altruistic tendency within the stigmatized group; and (3) stigmatization-induced negative emotions have a complete mediating effect between perceived relevance and altruistic tendency, as well as perceived stigma and altruistic tendency. For a country and nation, external stigma will promote the group becoming more united and mutual help. One wish to pass the buck but end up helping others unintentionally. We should not simply blame others, including countries, regions, and groups under the outbreak of COVID-19, and everyone should be cautious with the words and actions in the Internet public sphere.

Individuals with different levels of education have substantial differences in their willingness to communicate with malicious nodes in a group; thus, the results of evolution of opinions tend to differ significantly. In this study, malicious nodes, driven by the benefits of a game, were added to groups of individuals with different levels of education, and a theoretical model of the game theory of group opinions that introduces malicious nodes was established. The influence of the proportion of malicious node spreading messages, the extent of tampering when malicious nodes spread messages, and the distribution of education levels in the group on the evolution of group opinions were considered. It was found that the rate of evolution of group opinions declined in groups with higher average education levels. The results of this study can be used to explain the phenomenon of fewer knowledge exchange behaviors in communities with high education levels, as is found in actual sociology. The reason is that highly educated individuals are more affected by distorted news when communicating. Therefore, the loss of communication with malicious nodes is greater, resulting in lower vigilance and willingness to communicate.

In recent years, the research of chaos theory has developed from simple cognition and analysis to practical engineering application. In particular, hyperchaotic systems with more complex and changeable chaotic characteristics are more sensitive and unpredictable, so they are widely used in more fields. In this paper, two important engineering applications based on hyperchaos pseudorandom number generator and image encryption are studied. Firstly, the coupling 6D memristive hyperchaotic system and a 2D SF-SIMM discrete hyperchaotic mapping are used as the double entropy source structure. The double entropy source structure can realize a new PRNG that meets the security requirements, which can pass the NIST statistical test when the XOR postprocessing method is used. Secondly, based on the double entropy source structure, a new image encryption algorithm is proposed. The algorithm uses the diffusion-scrambling-diffusion encryption scheme to realize the conversion from the original plaintext image to the ciphertext image. Finally, we analyze the security of the proposed PRNG and image encryption mechanism, respectively. The results show that the proposed PRNG has good statistical output characteristics and the proposed image encryption scheme has high security, so they can be effectively applied in the field of information security and encryption system.

Informal coercive tactics play an important role in maintaining political and social order in authoritarian regimes today, a fact variously attributed to the state’s incapacity to monopolize coercive force and to the strategic concealment of repression from international society. Studying the coercive tactics used by the Chinese government, this article directs attention to how state institutions and strategies create incentives for state agents to delegate coercion to third parties. In particular, this article recognizes the importance of Chinese leaders’ traditional preference to rely on third parties rather than formal state force for social control, and also the impressive improvements in the institutionalization of state coercion after the start of extensive legal reforms in the late 1970s. More important, however, is the multilayered and decentralized state structure that creates tight constraints on local officials and therefore motivates them to use informal coercion. The state structure in China is conducive to informal coercion in two ways. First, when local officials pursue local or private interests that diverge from central interests, informal coercion helps them overcome procedural barriers and avoid scrutiny from above. Second, although central and other upper authorities tend to restrict local officials’ use of force, they often exert considerable pressure on local authorities to fulfill various tasks that require strong coercion. Such conflicting or unfunded mandates have frequently prompted the use of informal coercive tactics. This study highlights the difficulty of holding local government officials accountable with formal institutions in China.

One heated argument in recent years concerns whether requiring real names supervision on social media will inhibit users' participation in discoursing online speech. The current study explores the impact of identification, perceived anonymity, perceived risk, and information credibility on participating in discussions on moral/ethical violations event on social network sites (SNS) in China. In this study, we constructed a model based on the literature and tested it on a sample of 218 frequent SNS users. The results demonstrate the influence of identification and perception of anonymity: although the relationship between the two factors is negative, both are conducive to participation in discussion on moral/ethical violation topics, and information credibility also has a positive impact. The results confirmed the significance of risk perception on comments posted about moral/ethical violation. Our results have reference value for identity management and internet governance. Policies regarding users’ real names on the internet need to take into account the reliability of the identity authentication mechanism, as well as netizens’ perceptions of privacy about their identity and the necessity of guaranteeing content and information reliability online. We also offer some suggestions for future research, with a special emphasis on applicability to different cultures, contexts, and social networking sites.