bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Route Planning Method of Dual Aircraft Rescue Based on Block Chain Technology
Authors: Liu Lifeng
Published: July 2019

The dynamic change of rescue environment after disaster can greatly improve the efficiency of rescue by adjusting flight routes in real time according to the latest rescue environment and rescue tasks detected by aircraft. In this paper, the block chain technology is used to complete the real-time transmission of dynamic tasks and environmental information, and then the AI algorithm is used to realize the dynamic adjustment of flight route: realizing the real-time adjustment of flight route under the circumstances of dynamic change of rescue mission and deterioration of planning environment; the experimental results show that with the real-time transmission of threat information, threat detection and processing are realized, and threat information is localized. In this way, the transmission time of threat information and mission information and command center is shortened, and the efficiency and reliability of rescue are improved.
From One-size-fits-all Teaching to Adaptive Learning: The Crisis and Solution of Education in The Era of AI
Authors: Yang Shudong , Tian Huiyi , Sun Lin , Yu Xueying
Published: July 2019

With the change of micro environmental variables such as internet technology, AI technology, the upgrade of education consumption, there has been a profound change in education, and then the value network created by undergraduates, teachers, employers and other stakeholders will be also changed. The crisis faced by education is the multiple trust crises among stakeholders, and the contradiction between the personal needs of undergraduates (personal desire for development, personal maturity cycle, personal growth rate, etc.) and the One-size-fits-all teaching is the main aspect of the multiple trust crises. Therefore, establishing the concept of adaptive learning and shifting the focus of reform from One-size-fits-all teaching to personalized education is the way for educational reform in the future. The reform should firmly establish the principles of cognitive science obeying, interest activating, diversity cultivating, and balance keeping. Evidence-based education, mastery learning, etc. are the core elements of design of adaptive learning environment. The theoretical base of this research is Piaget’s cognitive developmental psychology and adaptive learning theory. It applies educational theories and educational techniques, such as evidence-based education, OBE, mastery learning, etc., to the construction of the adaptive learning environment. It provides an overview of the main modules and algorithms of the environment, with the aim of using the top-level design to enable the hidden functions of education by the soft environment.
Sleep Staging Based on Energy and Complexity Characteristics of Sleep EEG Signals
Authors: Li Xiaobo , Ren Chunhui , Zou Xiao
Published: July 2019

Nowadays, people’s sleep problems become more and more serious with the increase of pressure in social life. Sleep staging is the key step in the diagnosis of sleep diseases. The traditional manual staging has the drawbacks of consuming manpower and time, and the standard is difficult to unify. In order to effectively realize automatic sleep staging, a sleep staging method based on EEG energy characteristics and complexity is proposed in this paper. Because the complexity of EEG signal and the energy of each characteristic wave change regularly with the different sleep period, sleep period can be distinguished effectively based on these features. Firstly, FIR band-pass filter is used to extract the characteristic wave from EEG signal and calculate its energy. Then the complexity of each sleep period is calculated. Finally, the improved support vector machine is used to classify the sleep stage. The experimental results show that the method proposed in this paper is simple and effective, and has good clinical application value.
Design and Implementation of VR Multi-Dimensional Intelligent Tourism Information System
Authors: Kong Dehua , Li Xing , Zhang Bo
Published: July 2019

Intelligent tourism is the inevitable trend of tourism development. It perfectly integrates computer information technology and tourism to provide users with a good experience. With the help of three-dimensional computer graphics, wide-angle (wide-field) stereo display technology, user tracking technology, stereo technology, tactile/mechanical feedback technology, voice input and output technology, VR-based multi-dimensional intelligent tourism system provides personalized services for users both online and offline. It is further changing the existing traditional access mode of scenic spots, providing double-line browsing access mode, both online and offline. It is enlarging the overall popularity of the scenic area, at the same time, improving the tourist reception capacity and service level, and providing more and more fun experience for tourists.
Application Research of Ethernet Communication System Based on UIP Protocol Stack
Authors: Wendi Xie , Ling Yao , Enliang Wang
Published: July 2019

This paper elaborates an implementation method of embedded system access Ethernet based on UIP stack, and describes the scheme design, hardware design and software design in detail. This system takes DSP (Digital Signal Processing) chip TMS320VC5510 as the control core, and chooses CS8900A as the network controller. Through the design of the protocol stack and the development of the underlying driver, it completes the ICMP test and TCP test, and it is applied to the portable communication eqUIPment to realize data communication in Ethernet. The process of realization is simple and the cost is low.
Analysis of Practical Path to Promote the “Double-micro” Interaction of Media in the Mobile Internet Era
Authors: Youwen Zhang
Published: July 2019

In the process of carrying out the interactive work of “double-micro” media, we should explore effective innovative ways, constantly innovate ideas and ways of thinking, and better adapt to the needs of the development of modern information society. Besides, it is also necessary to make full use of modern media equipment, such as mobile Internet, adopt a variety of online learning methods so as to enhance the comprehensive effect of “double-micro” media interaction, and realize the continuous upgrading of the interactive work of “double-micro” media. Based on the actual operation of modern network learning, this paper gradually analyses the obstacles it needs to overcome, and promotes the role of “double-micro” interaction in the media in the era of mobile Internet.
Design of embedded inter-board communication middleware based on LCM
Authors: Li Qing , Yin Xuehao , Wang Yang , Cui Kaihua , Zhu Tao
Published: July 2019

Aiming at the distributed architecture of embedded computer system, the network communication middleware is designed based on Lightweight Communication and Marshalling (LCM). In order to improve the reliability and performance of inter-board message interaction, middleware realizes the bidirectional named pipeline, message publication confirmation mechanism, subscription message multithreading processing mode and other improved design schemes, and provides the standardized programming interface while inheriting the topic of “publish-subscribe” based on LCM. Finally, the message transmission delay design was tested on the hardware (Loongson 2K1000 processor) and software (VxWorks operating system) platform. The results show that the message transmission delay is very close to that of traditional UDP by using LCM-based embedded inter-board network communication middleware.
Implementation of attractions roaming system based on Unity 3D
Authors: An Jiahui , Cheng Xinrong , Wang Qing , Chen Hong
Published: July 2019

Combining virtual reality technology with the tourism industry to design a virtual roaming system for scenic spots, it can provide users with a new way of traveling that can enjoy the scenery without leaving home. This article designed the attraction roaming system, first using 3ds Max to simulate the building model for Unity 3D call; secondly in Unity 3D, build roaming scenes, including editing terrain, adding sound effects. Role interaction is very important in a roaming system. In this system, by writing a C# script, the character can move forward, backward, left, and right to achieve autonomous roaming. In order to be more realistic when roaming, the collision function is also added; finally, based on the cross-platform of Unity 3D, the system is released for the PC side. The attraction roaming system designed in this paper enables users to enjoy scenic spots in the virtual world.
Analysis system of power tiller’s general machine components based on VB and ANSYS
Authors: Lu Shiqing , Jin Hui , He Miao , Xu Zhe
Published: July 2019

Power tiller is one of the most representative agricultural machinery in hilly mountain areas in China. While the design and analysis of the power tiller’s components is still using the traditional methods with low efficiency. This paper developed a parametric finite element analysis system of the general machine components of power tiller based on ANSYS APDL and Visual Basic language. The system achieved the functions of ANSYS launching automatically, finite element parametric modeling, structural analysis and results output. The application of this analysis system is expected to shorten the design cycle and improve analysis efficiency and accuracy of the power tiller’s general machine components.
Research on Traffic Control and Induction Collaborative Framework of Smart City in the Environment of Vehicle Network
Authors: Wang ZhengQin
Published: July 2019

At present, how to use the advanced technologies such as Internet of Things and Internet of Vehicles technology, high-precision Beidou positioning technology, big data technology and artificial intelligence technology to integrate and develop the road network resources of existing large and medium-sized cities is domestic. Research hotspots in the academic and engineering fields. This paper deeply analyzes the operation mechanism of traffic control and traffic flow guidance system, and focuses on the application of traffic control and induced coordination. It is proposed to combine multi-agent theory and intelligent decision theory in traffic coordination control to better realize traffic control and induction, provide real-time road network information to better solve existing traffic congestion problems, and seek regional traffic. Optimized control provides a theoretical basis.
Design and Implementation of Intelligent Home Management System Based on Wireless Control Module
Authors: Wang Nan , Pan Aimin , Wei Liexiang
Published: July 2019

To solve the problem of “difficulty of control” in smart home, this paper proposes the design of smart home management system based on wireless control module. Users can use mobile phones to control household appliances in real time on the Internet, so as to achieve remote control and real-time monitoring, timely handling of emergencies and other functions. Therefore, home life, safety and convenience can be effectively improved.
A Vehicle-to-grid Framework Based on Electric Vehicle with Solar Panel
Authors: Hao Yu
Published: July 2019

In this paper, we extend previous studies of vehicle-to-grid technology with electric vehicle equipped with solar panel. Instead of connecting a solar power system into the grid, we consider a distributed scenario in which every electric vehicle has the power of collecting solar power and bidirectional charging abilities. Through mathematical formulation and numerical simulations, we demonstrate that our framework has superior advantages of incentivizing electric vehicles to install solar panels and discharge to the grid.
Bionic design and experiment of multidimensional propulsion device on water
Authors: Dai Zhiguang , Lv Jiangang , Liu Jinhua , Zhang Yu , Zhang Zhongzhi
Published: July 2019

In view of the present situation that the output thrust of traditional surface platform propulsion device is unidimensional and its amphibious capability is limited, based on the high-speed movement principle of basilius treading water, this paper designs a multidimensional surface propulsion device to realize the multidimensional output of torque, lifting force and propulsion force. Combined with the square platform, the controllable parameters of the multidimensional surface propulsion device are analyzed from the perspective of navigation dynamics. Finally, the prototype test, the water cube propulsion drive car body realizes high speed sailing boat type water skiing, with an average elevation of 10.6°.
Research and Development of Intelligent Integrated Conference Service Platform
Authors: Zhang Jiankang , Ni Xiaowei , Fan Jiaxuan
Published: July 2019

With the popularization of mobile terminals and the rapid development of Internet technology, the “Internet +” platform has become the infrastructure of future economic life and is the main ways of the future digital economy and the resource allocation. Focusing on user needs and taking the user’s experience as the core, the data-driven innovative intelligent integrated conference service platform will effectively integrate conference resources and provide personalized conference services. Based on the innovative thinking of the Internet, this paper introduces the “Internet + Conference” model to develop an intelligent integrated conference service platform, expound the architecture and a business model to explore the two applied Internet meeting innovation mode of thinking, create an intelligent conference, realize efficient collaboration and sharing of information resources to give full play to the platform role of the conference.
An improved wavelet analytical method for studying particle dynamics of the passive layer within a granular drum
Authors: Mou Shihang , Yang Hui , Li Ran , Wang Bide , Sun Qicheng , Kong Ping
Published: July 2019

In this study, conventional threshold way has many defects, for example, the way of extraction of signal processing for the <δν2> and experimental statistics depend on several subjective criteria during the analysis process. Therefore, we introduce another new way of using wavelet analysis that can be extracted valid signals from noise. The results of experiment indicate that it can distinguish noise from the signal <δν2>. Compared with the conventional way, the new method has better statistical distribution map of the <δν2> and smaller error.
Development of the Detection Arm of Multichannel Geometry Pig of Oil and Gas Pipeline
Authors: Xiaolong Li , Jinzhong Chen , Yilai Ma , Renbi He , Shuanyi Liu , Defu Yang
Published: July 2019

The geometry pig is widely used to detect pipeline geometry deformation in the field of oil and gas pipeline. As the core component, the detecting arm is very important for pipeline deformation detection. Firstly, this paper introduces the composition and principle of the detection arm system. Secondly, the design principles and methods of sensor circuit are described from the chip selection and circuit design. Finally, the layout of the spring and the key structure design method of the detection arm are discussed.
Online IGBT Temperature Measurement via Leakage Current in HTRB Test
Authors: Guo Chunsheng , Cai Wenyi , Li Jinyuan , Wang Sijin , Wei Lei , Li Yaosheng
Published: July 2019

To evaluate the reliability of endure high voltage when IGBT is turned off and eliminate the defective devices, HTRB (High Temperature Reverse Bias) test is one of the necessary tests for IGBT before it’s produced. According to the IEC standard, DUTs (Device Under Test) are usually blocked, and bear forward bias voltage, which is preferably 80% of VCESmax. During the HTRB test, DUT junction temperature should be set at maximum virtual junction temperature Tvj(max) which is usually between 125°C to 150°C. Due to high voltage, even though the leakage current is very low, high-power semiconductor devices generate dissipated power during HTRB test, which lead to junction temperature increase. And to access the reliability accurately, the rise of temperature cannot be neglected. To insure the test is carry out at standard temperature, this paper monitors DUTs junction temperature by using leakage current as a TSEP (Temperature Sensitive Electrical Parameter),. The experiment proofs that higher the junction temperature is, the more accurate the measure results will be, in the operating temperature range. In this paper, thermal resistance measurement is used to evaluate the validity of this method.
Analysis on the performance of the drive machine braking systems for traction lifts
Authors: Kong Shuai , Ling Zhangwei , Zheng Mulin , Jin Yinde , Zhou Zhenchao
Published: July 2019

The drive machine and the braking system are quite important to the safety of lifts. The redundancy-type brake is given usually more than one brake responsibility. In order to know the safety situation of the braking performances of drive machines after China’s new regulations issued, the type test results of 57 drive machine samples are summarized and analysed, including the sets of mechanical parts, the braking performance when all groups work together and the braking performance when each group works separately. The result shows that most (about 93%) drive machines are equipped with 2 sets of mechanical braking parts. The average of the ratio of braking torque to output torque is 3.16. The average of the sum of braking torque that generated by every group works separately just equals to the whole braking torque.
Design of Mobile Learning System for Courses of Computer Science and Technology
Authors: Junxiang Gao , Yu Huang
Published: July 2019

In recent years, mobile learning system is increasingly applied in colleges and universities due to its promising capability. This paper proposed a design of mobile learning system for courses of computer science and technology. The architecture was described, and the detailed scheme of the system was given including server and client solution. The system adopted Client/Server structure, and it supported Android and iOS operating systems. The relationship of each level and the data structure of each model were designed according to the business logic. Consequently the client program was developed based on real time video transmission protocols of RTP/RTCP/RTSP. The main functions of mobile learning system included curriculum center, teacher-student interaction, assignment and project. This design provided a learning platform for the students majoring computer science and technology. Using hand-hold mobile terminal devices, students can study courses anywhere and anytime through video, voice, picture, text and other media.
Protein Secondary Structure Online Server Predictive Evaluation
Authors: Zhu Shuping , Liu Yihui
Published: July 2019

The prediction of protein secondary structure is of great significance for studying the function of proteins and for making progress in the field of bioinformatics. Since 1951, the secondary structure of predicted proteins has been proposed. After 66 years of development, the prediction method has been continuously optimized, and the accuracy rate has exceeded 80%. Continuous Automated Model Evaluation (CAMEO) gives a prediction of protein tertiary structure evaluation for many current prediction methods, and secondary structure evaluation has not been achieved. In response to this problem, six servers were selected: PSRSM, MUFOLD, SPIDER, RAPTORX, JPRED and PSIPRED to evaluate the predicted secondary structure. The latest released protein from the Protein Data Bank (PDB) was applied just to ensure that the test set is not included in the training set. In the experiments of which protein homology was 30%, 50%, 70% and 90%, the obtained accuracy of PSRSM for Q3 was 91.44%, 88.12%, 90.17% and 87.39%, respectively. And the accuracy is higher than the best server among other prediction serves---MUFOLD, by 3.19%, 1.33%, 2.19% and 1.72%, correspondingly. It is proved that PSRSM has a better prediction quality than other servers for the same kind of homology data, the Sov and boundary accuracy as well. This paper focuses on analyzing the operating methods and corresponding results of various servers, thus, it is safe to say that the prediction of protein secondary structure should be studied on perspectives of big data, templates and deep learning.
Design of Visual Similation System for Carried-Aircraft Recovery Mode Based on AcoreOS
Authors: Fan He , Longjie Zhang , Tao Sun
Published: July 2019

Based on the AcoreOS operating system, a visual simulation system for the recovery process of Carried-Aircraft is designed. The geometry model of aircraft is established, then the geometric model is driven by the AcoreOS operation system kernel task scheduling mechanism, using the development environment LambdaAE software to carry out software implementation of simulation. The simulation results show that the system can help the commander in command.
Time series forecasting of stock market index based on ENWMPCA model
Authors: Guo Zhiqiang , Wang Xiao , Zeng Yali , Yang Jie
Published: July 2019

Aiming at the high dimension of factors affecting the stock market index, and the problem that MPCA algorithm cannot distinguish the contribution of different eigenvectors to financial time series forecasting, eigenvalue normalization weighted multilinear principal component analysis (ENW-MPCA) is put forward. Due to the existence of correlation between stock markets, 34 technical indexes of 7 stock markets are selected to construct a three-dimensional tensor model. Eigenvectors of different eigenvalues have different contributions to the prediction accuracy of MPCA algorithm, thus adopt ENW-MPCA algorithm for the feature extraction, which can distinguish the different contribution of eigenvectors corresponding to different eigenvalues to the prediction while reducing dimension. Then using support vector machine for regression prediction, the prediction value of financial time series is obtained. Experimental results on the Hang Seng Index shows that, compared with the MPCA, the forecasting error of ENW-MPCA is smaller and the prediction accuracy is improved to a certain extent. This indicates that the proposed algorithm can fully retain the internal structure of stock time series, proving its validity and practicability.
Research on the Innovation and Application of Computer Communication Technology in Public Management
Authors: Chen Jiaxiong
Published: July 2019

Computer technology promotes the development of big data, and big data provides support for the development of computer technology. These provide a solid foundation for the wisdom of public management and are also widely used in various fields of society. However, issues such as information sharing barriers also affect the quality and level of public management and need to be improved. This paper analyzes the current situation of digital public management in China, as well as the impact of big data on public management, and proposes suggestions for the wisdom of public management.
A Meter-Bus Master Station Interface Circuit Based on Transistor Amplification Characteristics
Authors: Cheng-ying Yang , Yong Chen
Published: July 2019

This paper introduces a new Meter-Bus master station interface circuit based on a single power supply. By utilizing the switching characteristics and amplification characteristics of the triode, the level signal conversion and signal transmission are realized by fully combining the cut-off region of the triode to work, the linear amplification of the amplification region, and the low-voltage differential conduction of the saturation region. The M-bus master circuit of the prior art solution is usually constructed with many separate components, and the whole circuit also needs positive and negative dual power supplies, so the circuit is very complicated, the circuit failure rate is high, and the cost of the circuit is also high. The circuit described in this paper solves the above technical problems of the current Meter-BUS master circuit.
Study on wake effect of series fans
Authors: Zhang Zhi-yang , Hu Rong , Wei Min , Zhang Li-xin , Shi Ning-qiang , Zhang Xin-wang
Published: July 2019

Within the range of finite land resources, in order to improve the power generation efficiency of wind farms and reduce the impact of wake effects on the output power of fans, the rationality of wind farm fan layout is very important. The wake velocity and output power of two 2.5MW experimental fans in series 5D spacing are obtained by means of Doppler measured anemometer of windcube2. Based on CFX numerical simulation method, the simulation of the wake field is carried out by ANSYS software. The results showed that the fan spacing of 5D, the simulation and experimental results were basically the same. As the axial distance increased, the axial velocity first decreased and then increased, gradually recovered the incoming wind speed. The radial velocity and the tangential velocity amplitude and frequency fluctuation of different sections at the same angle were gradually reduced. The amplitude and frequency fluctuation of the tangential velocity were the largest at 3D, and were the minimum at 8D. The amplitude and frequency fluctuation of the radial velocity were the largest at 5D, and were the minimum at 3D. The velocity at the center of the bub gradually increased, and the velocity variation was the most obvious at 3D. The simulation speed first appeared an upward trend. Due to the superposition of the upstream fan wake, the output power of the downstream fan was greatly affected. Therefore, in the actual planning of the wind farm, the downstream fan should not be completely arranged in the wake field of the upstream fan.
Group size and social status affect scent marking in dispersing female meerkats
Authors: Morales-González Ana , Ruíz-Villar Héctor , Ozgul Arpat , Maag Nino , Cozzi Gabriele
Published: July 2019

Many animal species use scent marks such as feces, urine, and glandular secretions to find mates, advertise their reproductive status, and defend an exclusive territory. Scent marking may be particularly important during dispersal, when individuals emigrate from their natal territory searching for mates and a new territory to settle and reproduce. In this study, we investigated the scent-marking behavior of 30 dispersing female meerkats (Suricata suricatta) during the three consecutive stages of dispersal—emigration, transience, and settlement. We expected marking patterns to differ between dispersal stages, depending on social circumstances such as presence of unrelated mates and social status of the individuals within each dispersing coalition and also to be influenced by water and food availability. We showed that defecation probability increased with group size during the settlement stage, when newly formed groups are expected to signal their presence to other resident groups. Urination probability was higher in subordinate than in dominant individuals during each of the three dispersal stages and it decreased overall as the dispersal process progressed. Urine may, thus, be linked to advertisement of the social status within a coalition. Anal marking probability did not change across dispersal stages but increased with the presence of unrelated males and was higher in dominants than in subordinates. We did not detect any effect of rain or foraging success on defecation and urination probability. Our results suggest that feces, urine, and anal markings serve different communication purposes (e.g., within and between-group communication) during the dispersal process.
Histone methyltransferase SETDB1 promotes colorectal cancer proliferation through the STAT1-CCND1/CDK6 axis
Authors: Yu Lu , Ye Feng , Li Yi-Yi , Zhan Yi-Zhi , Liu Yang , Yan Hong-Mei , Fang Yuan , Xie Yu-Wen , Zhang Feng-Jiao , Chen Long-Hua , Ding Yi , Chen Ke-Li
Published: July 2019

Upregulation of histone methyltransferase SET domain bifurcated 1 (SETDB1) is associated with poor prognosis in cancer patients. However, the mechanism of oncogenicity of SETDB1 in cancer is hitherto unknown. Here, we show that SETDB1 is upregulated in human colorectal cancer (CRC) where its level correlates with poor clinical outcome. Ectopic SETDB1 promotes CRC cell proliferation, whereas SETDB1 attenuation inhibits this process. Flow cytometry reveals that SETDB1 promotes proliferation by driving the CRC cell cycle from G0/G1 phase to S phase. Mechanistically, SETDB1 binds directly to the STAT1 promoter region resulting in increased STAT1 expression. Functional characterization reveals that STAT1-CCND1/CDK6 axis is a downstream effector of SETDB1-mediated CRC cell proliferation. Furthermore, SETDB1 upregulation is sufficient to accelerate in vivo proliferation in xenograft animal model. Taken together, our results provide insight into the upregulation of SETDB1 within CRC and can lead to novel treatment strategies targeting this cell proliferation-promoting gene.
On Measles, Vaccination, Social Media Activism, and How to Win Back Our Role as Our Patients’ Best Advocates
Authors: Oehler Richard L
Published: July 2019

Once declared transmission free in the United States less than 20 years ago, measles and other vaccine-preventable diseases have made a spectacular comeback. Waning public support for childhood immunization and subsequent recent outbreaks of vaccine-preventable diseases have been spawned by several technological and social factors, including the erosion of the provider-patient relationship, the emergence of internet-based patient resources and social media sites, and the rise of online healthcare activism. New tools are needed for physicians and healthcare providers to reverse this trend and regain our role as our patients’ best advocates.
Cardiovascular long-term outcome and prophylactic treatment patterns in peripheral arterial disease in a population-based cohort
Authors: Sartipy Fredrik , Lundin Fredrik , Wahlberg Eric , Sigvant Birgitta
Published: July 2019

Aims

This study evaluates 10-year follow-up data on associated comorbidity, mortality, and pharmacological treatment patterns for men and women with different stages of peripheral arterial disease (PAD) in a population-based setting.

Methods and results

This was a prospective observational population-based cohort study, based on physical examinations and questionnaires at baseline supplemented with national register data between 2005 and 2015. Subjects were placed in subgroups defined by ankle–brachial index levels and reported symptoms; asymptomatic PAD (APAD), intermittent claudication (IC), severe limb ischaemia (SLI), or references (Ref). Cox proportional hazards regression models were used for analysis with adjustments for sex and baseline age and comorbidity. The cohort consisted of 5080 subjects (45% males). At baseline, APAD, IC, and SLI were prevalent in 559 (11%), 320 (6.3%), and 78 (1.5%) subjects, respectively. A significant increased risk for cardiovascular (CV) death, even when adjusted for age and baseline morbidity, were noted in all PAD stages as compared with reference group with a small difference between APAD and IC, an adjusted hazard ratio 1.80 (confidence interval 1.45–2.22) and 1.95 (1.50–2.53), respectively. Only about 60% of PAD subjects received medical prophylactic treatment as recommended in guidelines.

Conclusion

Peripheral arterial disease subjects had significantly increased CV morbidity and mortality risks, especially males. Asymptomatic PAD subjects confer similar risk for CV events as symptomatic patients. Our findings motivate enhanced preventive efforts of all PAD stages, including in asymptomatic disease.
Molecular typing of Streptococcus agalactiae isolates of serotype Ia from tilapia in southern China
Authors: Su Youlu , Liu Chan , Deng Yiqin , Cheng Changhong , Ma Hongling , Guo Zhixun , Feng Juan
Published: July 2019

Streptococcus agalactiae is an important pathogen of tilapia causing enormous economic losses worldwide. In this study, multilocus sequence typing indicated that 75 S. agalactiae isolates from tilapia in southern China belonged to sequence type-7, as well as belonging to serotype Ia, as confirmed by multiplex PCR assay. The putative-virulence gene profiles and genetic variation of these strains were determined by three sets of multiplex PCR and multi-virulence locus sequencing typing (MVLST), respectively. Analysis of putative-virulence gene profiles showed that each strain harbored 18 putative-virulence genes but lacked lmb and scpB. Three putative-virulence genes (srr-1, bibA and fbsA) were further selected for MVLST analysis. Our data showed that the strains had 14 MVLST types (1–14) and clustered in three groups (Groups I–Ⅲ). The period of time during 2013 and 2014 was an important turning point for the differentiation of the putative-virulence genes of S. agalactiae, as type 1 within Group Ⅱ became the predominant MVLST type. There were significant differences in MVLST types of S. agalactiae isolated from different tilapia farming regions. MVLST assay may improve the discriminatory power and is suitable for understanding the epidemiology of S. agalactiae serotype Ia and screening multivalent vaccine candidate strains.
A gene regulatory network explains RET–EDNRB epistasis in Hirschsprung disease
Authors: Chatterjee Sumantra , Chakravarti Aravinda
Published: July 2019

Disruptions in gene regulatory networks (GRNs), driven by multiple deleterious variants, potentially underlie complex traits and diseases. Hirschsprung disease (HSCR), a multifactorial disorder of enteric nervous system (ENS) development, is associated with at least 24 genes and seven chromosomal loci, with RET and EDNRB as its major genes. We previously demonstrated that RET transcription in the ENS is controlled by an extensive GRN involving the transcription factors (TFs) RARB, GATA2 and SOX10 and other HSCR genes. We now demonstrate, using human and mouse cellular and animal models, that EDNRB is transcriptionally regulated in the ENS by GATA2, SOX10 and NKX2.5 TFs. Significantly, RET and EDNRB expression is regulated by their shared use of GATA2 and SOX10, and in turn, these TFs are controlled by EDNRB and RET in a dose-dependent manner. This study expands the ENS development GRN to include both RET and EDNRB, uncovers the mechanistic basis for RET–EDNRB epistasis and emphasizes how functionally different genes associated with a complex disorder can be united through a common GRN.
Long-term firm growth: an empirical analysis of US manufacturers 1959–2015
Authors: Dosi Giovanni , Grazzi Marco , Moschella Daniele , Pisano Gary , Tamagni Federico
Published: July 2019

Firm growth is an essential feature of market economies, shaping together macroeconomic performance and the evolution of industry structures. As a potential indicator of organizational “fitness” within a competitive environment, firm growth is also a central concern to both the practice and theory of business strategy. Despite both its theoretical and practical importance, though, growth remains a poorly understood property of firms. While previous studies have documented the fat-tailed nature of firm growth rates, we know far less about the patterns of growth rates over long periods of time. For instance, do “fast growers” tend to maintain their relative growth rates advantages over long periods or is superior growth a transitory phenomenon? Is, as predicted by evolutionary and capability-based theories of the firm, the process of firm growth path-dependent or is it more akin to a random walk? The answers to these questions are central to building a robust theory of firm growth. This article attempts to address this gap in our empirical knowledge of firm growth using a dataset that spans 50 years, which allows the abandonment of the assumption, common to all incumbent studies, that the stochastic paths of all firms stem from the same generating process. These exploratory results indicate that growth rate persistence is there and may be even substantial for some firms, but it is rare. We also study the links between the micro-properties of firm growth within sectors and the patterns of aggregate growth of these same sectors. Indeed, we find circumstantial but widespread evidence that heterogeneity across firms correlates with industry dynamism.
Mediastinal liposarcoma: a rare visceral mediastinal tumour
Authors: Krishnasamy Sivakumar , Krishna Nair Ashvin , Hashim Shahrul Amry , Raja Mokhtar Raja Amin
Published: July 2019

Liposarcoma is the second most common type of soft tissue malignancy in adults. They are malignant tumours with a mesenchymal origin. Mediastinal liposarcoma accounts for <1% of mediastinal tumours and 2% of liposarcoma. We report a patient with mediastinal liposarcoma who presented with cardiac tamponade, 25 years after the initial liposarcoma in the popliteal fossa.
The current scope of healthcare-associated infection surveillance activities in hospitalized immunocompromised patients: a systematic review
Authors: Valentine Jake C , Hall Lisa , Verspoor Karin M , Worth Leon J
Published: July 2019

Background

Immunocompromised patients are at increased risk of acquiring healthcare-associated infections (HAIs) and often require specialized models of care. Surveillance of HAIs is essential for effective infection-prevention programmes. However, little is known regarding standardized or specific surveillance methods currently employed for high-risk hospitalized patients.

Methods

A systematic review adopting a narrative synthesis approach of published material between 1 January 2000 and 31 March 2018 was conducted. Publications describing the application of traditional and/or electronic surveillance of HAIs in immunocompromised patient settings were identified from the Ovid MEDLINE®, Ovid Embase® and Elsevier Scopus® search engines [PROSPERO international prospective register of systematic reviews (registration ID: CRD42018093651)].

Results

In total, 2708 studies were screened, of whom 17 fulfilled inclusion criteria. Inpatients diagnosed with haematological malignancies were the most-represented immunosuppressed population. The majority of studies described manual HAI surveillance utilizing internationally accepted definitions for infection. Chart review of diagnostic and pathology reports was most commonly employed for case ascertainment. Data linkage of disparate datasets was performed in two studies. The most frequently monitored infections were bloodstream infections and invasive fungal disease. No surveillance programmes applied risk adjustment for reporting surveillance outcomes.

Conclusions

Targeted, tailored monitoring of HAIs in high-risk immunocompromised settings is infrequently reported in current hospital surveillance programmes. Standardized surveillance frameworks, including risk adjustment and timely data dissemination, are required to adequately support infection-prevention programmes in these populations.
Happy Mother’s Day? Maternal and neonatal mortality and morbidity in low- and middle-income countries
Authors: van den Broek Nynke
Published: July 2019

At least 800 women die each day during pregnancy or birth and more than 15 000 babies each day are stillborn or die in the first month of life. Almost all of these deaths occur in low- and middle-income countries. Many more women and babies are known to suffer morbidity as a result of pregnancy and childbirth. However, reliable estimates of the burden of physical, psychological and social morbidity and comorbidity during and after pregnancy are not available. Although there is no single intervention or ‘magic bullet’ that would reduce mortality and improve health, there are evidence-based care packages which are defined and agreed internationally. A functioning health system with care available and accessible for everyone at all times is required to ensure women and babies survive and thrive.
Are the Contents of International Treaties Copied and Pasted? Evidence from Preferential Trade Agreements
Authors: Allee Todd , Elsig Manfred
Published: July 2019

Most accounts of international negotiations suggest that global agreements are individually crafted and distinct, while some emerging scholarship suggests a heavy reliance on models and templates. In this research, we present a comprehensive test of whether new international treaties are heavily copied and pasted from past ones. We specify several reasons to expect widespread copying and pasting, and argue that both the most and least powerful countries should be most likely to do so. Using text analysis to examine several hundred preferential trade agreements (PTAs), we reveal that most PTAs copy a sizable majority of their content word for word from an earlier agreement. At least one hundred PTAs take 80 percent or more of their contents directly from a single, existing treaty—with many copying and pasting 95 percent or more. These numbers climb even higher when we compare important substantive chapters of trade agreements, many of which are copied and pasted verbatim. Such copying and pasting is most prevalent among low-capacity governments that lean heavily on existing templates, and powerful states that desire to spread their preferred rules globally. This widespread replication of existing treaty language reshapes how we think about international cooperation, and it has important implications for literatures on institutional design, policy diffusion, state power, and legal fragmentation.
Forming Pop III binaries in self-gravitating discs: how to keep the orbital angular momentum
Authors: Chon Sunmyon , Hosokawa Takashi
Published: July 2019

The disc fragmentation is a possible process leading to the formation of Population III stellar binary systems. However, numerical simulations show diverse fates of the fragments; some evolve into stable binaries and others merge away with a central star. To clarify the physics behind such diversity, we perform a series of 3D hydrodynamics simulations in a controlled manner. We insert a point particle mimicking a fragment in a self-gravitating disc, where the initial mass and position are free parameters, and follow the orbital evolution for several tens of orbits. The results show great diversity even with such simple experiments. Some particles shortly merge away after migrating inward, but others survive as the migration stalls with the gap opening in the disc. We find that our results are well interpreted postulating that the orbital angular momentum is extracted by (i) the gravitational torque from the disc spiral structure, and (ii) tidal disruption of a gravitationally bound envelope around the particle. Our analytic evaluations show the processes (i) and (ii) are effective in an outer and inner part of the disc, respectively. There is a window of the gap opening in the middle, if the envelope mass is sufficiently large. These all agree with our numerical results. We further show that the binaries, which appear for the ‘survival’ cases, gradually expand while accreting the disc gas. Our theoretical framework is freely scalable to be applied for the present-day star and planet formation.
Planetary system detection by estimating the covariance of coronagraphic lucky images
Authors: Cagigas Miguel A , Cagigal Manuel P , Valle Pedro J , Canales Vidal F , Fuentes Antonio , López Roberto
Published: July 2019

In this paper, we review two different methods to increase image contrast and propose the combination of both to detect faint companions surrounding a host star. Coronagraphy allows us to block light coming from the host star so that the residual star light can be reduced by several orders of magnitude. On the other hand, estimating the Covariance of Lucky Images (COELI) is a proven method to detect faint companions from ground-based telescope images. The dynamic range of the detection camera limits this technique. Hence, the application of COELI to coronagraphic images may increase the magnitude range of the detectable companions. COELI only requires the existence of a reference, which can be obtained using an existing stellar companion or using a coronagraphic mask designed to create a faint image of the host star. We provide an analysis of the combination of the techniques by processing coronagraphic images obtained by the William Herschel Telescope.
On the detection of supermassive primordial stars – II. Blue supergiants
Authors: Surace Marco , Zackrisson Erik , Whalen Daniel J , Hartwig Tilman , Glover S C O , Woods Tyrone E , Heger Alexander , Glover S C O
Published: July 2019

Supermassive primordial stars in hot, atomically cooling haloes at z ∼ 15–20 may have given birth to the first quasars in the Universe. Most simulations of these rapidly accreting stars suggest that they are red, cool hypergiants, but more recent models indicate that some may have been bluer and hotter, with surface temperatures of 20 000–40 000 K. These stars have spectral features that are quite distinct from those of cooler stars and may have different detection limits in the near-infrared today. Here, we present spectra and AB magnitudes for hot, blue supermassive primordial stars calculated with the tlusty and cloudy codes. We find that photometric detections of these stars by the James Webb Space Telescope will be limited to z ≲ 10–12, lower redshifts than those at which red stars can be found, because of quenching by their accretion envelopes. With moderate gravitational lensing, Euclid and the Wide-Field Infrared Space Telescope could detect blue supermassive stars out to similar redshifts in wide-field surveys.
British military women: combat exposure, deployment and mental health
Authors: Jones N , Greenberg N , Phillips A , Simms A , Wessely S
Published: July 2019

Background

Internationally, women are about to undertake combat duties alongside their male colleagues. The psychological effect of this policy change is largely unknown.

Aims

To explore the mental health impact of combat exposure among military women.

Methods

Self-report, between-subjects survey data were collected in Iraq and Afghanistan on four occasions between 2009 and 2014 (n = 4139). Differences in mental health, stigmatization, deployment experiences, intimate relationship impact, perception of family support levels, unit cohesion, leadership and help-seeking were compared between deployed men and women. Comparisons were repeated with the study sample stratified by level of combat exposure. Outcomes were examined using logistic regression adjusted for socio-demographic, mental health and military factors.

Results

Overall, 4.1% of women and 4.3% of men reported post-traumatic stress disorder (PTSD) (odds ratio (OR) 1.31, 95% confidence interval (95% CI) 0.70–2.46); 22% of women and 16% of men reported symptoms of common mental disorder (CMD) (OR 1.52, 95% CI 1.11–2.08). Women were less likely to report mental health-related stigmatization (OR 0.68, 95% CI 0.53–0.87), negative relationship impact from deployment (OR 0.69, 95% CI 0.49–0.98) and subjective unit cohesion (OR 0.69, 95% CI 0.53–0.90). Help-seeking for emotional problems was similar by gender (OR 1.22, 95% CI 0.84–1.77). Overall, outcomes were minimally impacted by level of combat exposure.

Conclusion

Although women experienced more CMD symptoms, PTSD symptoms were similar by gender. Subject to confirmation of the study findings, women may not require enhanced mental healthcare during deployment for exposure-based conditions such as PTSD when undertaking the ground close combat role.
Prior Dengue Virus Infection Is Associated With Increased Viral Load in Patients Infected With Dengue but Not Zika Virus
Authors: Santiago Gilberto A , Sharp Tyler M , Rosenberg Eli , Sosa Cardona Iris I , Alvarado Luisa , Paz-Bailey Gabriela , Muñoz-Jordán Jorge L
Published: July 2019

To evaluate potential enhancement of Zika virus (ZIKV) infection among patients with prior dengue virus (DENV) infection, we compared loads of viral RNA among patients infected with ZIKV (n = 1070), DENV-2 (n = 312), or DENV-3 (n = 260). Compared to patients without prior DENV infection, patients with prior DENV infection had significantly higher mean loads of viral RNA if infected with DENV-2 (10.6 vs 11.6 log10 GCE/mL, respectively; t test, P < .0001) or DENV-3 (10.3 vs 10.9 log10 GCE/mL; P < .0001), but not ZIKV (4.7 vs 4.7 log10 GCE/mL; P = .959). These findings provide evidence against in vivo enhancement of ZIKV by anti-DENV antibodies.