bluuebunny/crossref_metadata_2025 huggingface dataset:
COVID-19 impact on junior doctor education and training: a scoping review
Authors: Seifman Marc Adam , Fuzzard Sibon K , To Henry , Nestel Debra
Published: March 2021

COVID-19 has had a significant impact on healthcare resources and the medical workforce. Clinically-based medical education is the principal source of learning, and this has been profoundly impacted by restrictions due to COVID-19. It follows that junior medical staff and their education would be significantly impacted due to the altered volume and breadth of their clinical exposure. Some literature has been published regarding the impact to medical training during COVID-19. This study sought to review junior medical staff perceptions and their reported impact of the COVID-19 pandemic on their education and training.

Nine databases (three Ovid MEDLINE databases, Embase, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature, Educational Resources Information Centre and PsychINFO) were searched for studies published in 1 January 2020 through 24 August 2020. Via a scoping review protocol, an iterative process was used to perform the identification, review and charting analysis of the reported outcomes and themes. Descriptive analysis was performed using quantitative and qualitative methods.

Of the 25 343 sources identified, 32 were included in the review. There were studies published from nearly all continents, predominantly in surgical journals, with a wide spread of specialties. Themes identified included the current impact of the pandemic in relation to continuation of and modifications to training programmes, as well as the future impact due to training requirements and career progression.

Junior medical staff report that the COVID-19 pandemic has had a significant impact on their education and training. Whether the changes imposed by the pandemic on education are temporary measures or permanent fixtures, and whether standards of competence may be impacted, is not yet known. This scoping review forms a basis for further investigation in the field.
Use of deep learning for detection, characterisation and prediction of metastatic disease from computerised tomography: a systematic review
Authors: Shivakumar Natesh , Chandrashekar Anirudh , Handa Ashok Inderraj , Lee Regent
Published: March 2021

CT is widely used for diagnosis, staging and management of cancer. The presence of metastasis has significant implications on treatment and prognosis. Deep learning (DL), a form of machine learning, where layers of programmed algorithms interpret and recognise patterns, may have a potential role in CT image analysis. This review aims to provide an overview on the use of DL in CT image analysis in the diagnostic evaluation of metastatic disease. A total of 29 studies were included which could be grouped together into three areas of research: the use of deep learning on the detection of metastatic disease from CT imaging, characterisation of lesions on CT into metastasis and prediction of the presence or development of metastasis based on the primary tumour. In conclusion, DL in CT image analysis could have a potential role in evaluating metastatic disease; however, prospective clinical trials investigating its clinical value are required.
Effects of interactions between transient granular flows and macroscopically rough beds and their implications for bulk flow dynamics
Authors: Choi C.E. , Goodwin G.R.
Published: March 2021

Steep-creek beds are macroscopically rough. This roughness causes channelized flow material to decelerate and dissipate energy, which are accounted for by depth-averaged mobility models (DMM). However, practical DMM implementations do not explicitly account for grain-scale basal interactions that influence macroscopic flow dynamics. In this study, we model flows using physical tests with smooth and macroscopically rough bases, and hence evaluate discrete element method (DEM) and DMM models. A scaling effect is identified relating to roughened beds: increasing the number of grains per unit depth tends to suppress dispersion, such that small-scale flows on smooth beds resemble large-scale flows on roughened beds, at least in terms of bulk density. Furthermore, the DEM shows that rougher beds reduce the peak bulk density by up to 15% compared to a smooth bed. Rough beds increase the vertical momentum transfer tenfold, compared to smooth ones. The DMM cannot account for density change or vertical momentum, so DMM flow depths are underestimated by 90% at the flow front and 20% in the body. The Voellmy model implicitly captures internal energy dissipation for flows on rough beds. The parameter ξ can allow velocity reductions due to rough beds observed in the DEM to be captured.
Spectral properties of local gauge invariant composite operators in the SU(2) Yang–Mills–Higgs model
Authors: Dudal D. , Egmond D. M. van , Guimarães M. S. , Palhares L. F. , Peruzzo G. , Sorella S. P.
Published: March 2021

The spectral properties of a set of local gauge (BRST) invariant composite operators are investigated in theSU(2) Yang–Mills–Higgs model with a single Higgs field in the fundamental representation, quantized in the ’t Hooft$$R_{\xi }$$Rξ-gauge. These operators can be thought of as a BRST invariant version of the elementary fields of the theory, the Higgs and gauge fields, with which they share a gauge independent pole mass. The two-point correlation functions of both BRST invariant composite operators and elementary fields, as well as their spectral functions, are investigated at one-loop order. It is shown that the spectral functions of the elementary fields suffer from a strong unphysical dependence from the gauge parameter$$\xi $$ξ, and can even exhibit positivity violating behaviour. In contrast, the BRST invariant local operators exhibit a well defined positive spectral density.
Hopf algebra gauge theory on a ribbon graph
Authors: Meusburger Catherine , Wise Derek K.
Published: March 2021

We generalize gauge theory on a graph so that the gauge group becomes a finite-dimensional ribbon Hopf algebra, the graph becomes a ribbon graph, and gauge-theoretic concepts such as connections, gauge transformations and observables are replaced by linearized analogs. Starting from physical considerations, we derive an axiomatic definition of Hopf algebra gauge theory, including locality conditions under which the theory for a general ribbon graph can be assembled from local data in the neighborhood of each vertex. For a vertex neighborhood with [Formula: see text] incoming edge ends, the algebra of non-commutative ‘functions’ of connections is dual to a two-sided twist deformation of the [Formula: see text]-fold tensor power of the gauge Hopf algebra. We show these algebras assemble to give an algebra of functions and gauge-invariant subalgebra of ‘observables’ that coincide with those obtained in the combinatorial quantization of Chern–Simons theory, thus providing an axiomatic derivation of the latter. We then discuss holonomy in a Hopf algebra gauge theory and show that for semisimple Hopf algebras this gives, for each path in the embedded graph, a map from connections into the gauge Hopf algebra, depending functorially on the path. Curvatures — holonomies around the faces canonically associated to the ribbon graph — then correspond to central elements of the algebra of observables, and define a set of commuting projectors onto the subalgebra of observables on flat connections. The algebras of observables for all connections or for flat connections are topological invariants, depending only on the topology, respectively, of the punctured or closed surface canonically obtained by gluing annuli or discs along edges of the ribbon graph.
The analysis of particles behavior under a delayed tristable system driven by multiplicative and additive noises
Authors: Zhang Gang , Shu Yichen , Zhang Tianqi
Published: March 2021

In this paper, the motion of Brownian particles driven by a delayed tristable system with multiplicative and additive Gaussian white noise is mainly studied. First, the effective potential function and stable state probability density function (PDF) are derived by using the theory of small-time delay approximation and the approximate Fokker–Planck equation (FPE), and the expression of mean first-passage times (MFPTs) is obtained by using the definition of the MFPTs and the steepest descent method. Then, the effects of the parameters which include noise intensities of multiplicative and additive noise, and correlation strength between two noises, and time delay, and the strength of time-delayed feedback on PDF and MFPTs are analyzed. Results demonstrate that the additive noise intensity has a more profound influence on PDF than the multiplicative noise intensity. The non-equilibrium phase transition of the system can be produced by the correlation strength of noises. In addition, in the behavior of the MFPTs, we can observe the noise-enhanced stability (NES) phenomenon induced by multiplicative noise intensity. Besides, delayed time plays an important role in MFPTs. Moreover, MFPT [Formula: see text] (stands for the Brownian particle moving from the left well to the middle well) is greater than [Formula: see text] (stands for the Brownian particle moving from the middle well to the left one).
Attenuation and Prediction of the Ground Vibrations Induced by High-Speed Trains Running Over Bridge
Authors: Zhang Yunshi , Lou Yu , Zhang Nan , Cao Yanmei , Chen Liu
Published: March 2021

This paper aims to study the transfer laws of vibration signals in the free field near a high-speed train line by conducting a field test. The characteristics of ground vibration acceleration were analyzed in the time and frequency domains, and a prediction method in the frequency domain was proposed. The results show: (1) there is a vibration amplification area away from the bottom of the pier under the influence of high-speed trains running over the bridge due to the fluctuation attenuation of the vibration waves; (2) the dominant peak frequency points in the frequency spectrum of the acceleration can be regarded as the resonance frequency induced by periodic loading; and (3) the soil vibration can be effectively predicted by the proposed method with a strong capability to defend the interference of environmental vibrations according to the comparison between the predicted value and the experimental data.
An Efficient Decision-Making Approach for Short Term Indoor Room Temperature Forecasting in Smart Environment: Evidence from India
Authors: Pandey Kamal , Basu Bhaskar , Karmakar Sandipan
Published: March 2021

“Smart cities” start with “Smart Buildings” that improve the quality of urban services while ensuring sustainability. The current scenario in India reveals that the corporate and residential building structures are incorporating various self-sustainable techniques. Out of the multiple factors governing the comfort of smart buildings, indoor room temperature is an important one, since it drives the need of cooling or heating through controlling systems. Around one-third of total energy consumption of commercial buildings in India is attributed to Heating, Ventilation and Air Conditioning (HVAC) systems. Accurate prediction of indoor room temperature helps in creating an efficient equilibrium between energy consumption and comfort level of the building, thus providing opportunities for efficient decision making for energy optimization. Considering Indian climatic and geographical conditions, this paper proposes an efficient decision making approach using Bayesian Dynamic Models (BDM) for short-term indoor room temperature forecasting of a corporate building structure. The results obtained from Bayesian Dynamic linear model, using Expectation Maximization (EM) algorithm, have been compared to standard Auto Regressive Integrated Moving Average (ARIMA) model, and have been found to be more accurate. Forecasting of indoor room temperature is a highly nonlinear phenomenon, so to further improve the accuracy of the linear models, a hybrid modeling approach has been proposed. The inclusion of state-of-the-art nonlinear models such as Artificial Neural Networks (ANNs) and Support Vector Regression (SVR) improves the forecasting accuracy of the linear models significantly. Results show that the hybrid model obtained using BDM and ANN is the best fit model.
Defaultable sovereign debts with macroeconomic conditions and periodic news
Authors: Li Weiping
Published: March 2021

This paper presents a default structural model of sovereign debt under macroeconomic conditions and periodic news. I model the macroeconomic conditions to be a finite state of Markov chain, and the periodic news to be a predictable factor in the drifting and the diffusion parts in the underlying value of the representative firm. The innovation of our model is to characterize the price of sovereign debt and the sovereign credit spread associated with macroeconomic conditions, and to model periodic news with both continuous factors and periodic factors. Both the defaultable yield-to-maturity, the sovereign credit spread and the duration are related to the finite state of Markov chain and periodic news. Furthermore, we obtain a closed-form solution for the two-state Markov chain associated to macroeconomic conditions and periodical information update.
On the Differentiation of Henstock and McShane Integrals
Authors: Chew Tuan Seng , Cabral Emmanuel A. , Benitez Julius V.
Published: March 2021

It is well known that the derivative of the primitive of 1-dimensional Henstock integral exists almost everywhere. Point-interval pairs used in the derivative are Henstock point-interval pairs, which are consistent with point-interval pairs used in the Henstock integral. Note that “almost everywhere” is a set of points, more precisely, the derivative does not exist on a set of points with measure zero. We can transform a set of Henstock point-interval pairs to a set of points with measure zero because of Vitali’s covering theorem. For 1-dimensional McShane integrals, [Formula: see text]-dimensional McShane and Henstock integrals, covering theorems of Vitali’s type cannot be applied. In this paper, we shall discuss differentiation of [Formula: see text]-dimensional McShane and Henstock integrals.
What Do CS Students Value in Industry Internships?
Authors: Minnes Mia , Serslev Sheena Ghanbari , Padilla Omar
Published: March 2021

Summer internships present an opportunity for Computer Science (CS) students to expand and test their skills in “the real world.” These multi-faceted experiences call on students to use technical tools and critical thinking in collaboration with others to solve problems. There are many opportunities for learning and growth: which of these do students find most valuable? In this project, we collect and analyze open-ended reflections by undergraduate CS students at the conclusion of a summer internship. We see that students focus on technical skills, expanding professional networks, and the satisfaction of completing a product that will be of use to others. These insights help inform academic programs that support Computer Science students engaging in these internships and strengthen their connection to on-campus education.
Developing Cost-Effective Blockchain-Powered Applications
Authors: Zarir Abdullah A. , Oliva Gustavo A. , Jiang Zhen M. (Jack) , Hassan Ahmed E.
Published: March 2021

Ethereum is a blockchain platform that hosts and executes smart contracts. Executing a function of a smart contract burns a certain amount of gas units (a.k.a., gas usage). The total gas usage depends on how much computing power is necessary to carry out the execution of the function. Ethereum follows a free-market policy for deciding the transaction fee for executing a transaction. More specifically, transaction issuers choose how much they are willing to pay for each unit of gas (a.k.a., gas price). The final transaction fee corresponds to the gas price times the gas usage. Miners process transactions to gain mining rewards, which come directly from these transaction fees. The flexibility and the inherent complexity of the gas system pose challenges to the development of blockchain-powered applications. Developers of blockchain-powered applications need to translate requests received in the frontend of their application into one or more smart contract transactions. Yet, it is unclear how developers should set the gas parameters of these transactions given that (i) miners are free to prioritize transactions whichever way they wish and (ii) the gas usage of a contract transaction is only known after the transaction is processed and included in a new block. In this article, we analyze the gas usage of Ethereum transactions that were processed between Oct. 2017 and Feb. 2019 (the Byzantium era). We discover that (i) most miners prioritize transactions based on their gas price only, (ii) 25% of the functions that received at least 10 transactions have an unstable gas usage (coefficient of variation = 19%), and (iii) a simple prediction model that operates on the recent gas usage of a function achieves an R-Squared of 0.76 and a median absolute percentage error of 3.3%. We conclude that (i) blockchain-powered application developers should be aware that transaction prioritization in Ethereum is frequently done based solely on the gas price of transactions (e.g., a higher transaction fee does not necessarily imply a higher transaction priority) and act accordingly and (ii) blockchain-powered application developers can leverage gas usage prediction models similar to ours to make more informed decisions to set the gas price of their transactions. Lastly, based on our findings, we list and discuss promising avenues for future research.
Electrochemical Formation of Nd–Ni Alloys in Molten CaCl2–NdCl3
Authors: Hua Hang , Yasuda Kouji , Konishi Hirokazu , Nohira Toshiyuki
Published: March 2021

The electrochemical formation of Neodymium–Nickel (Nd–Ni) alloys was investigated in a molten CaCl2–NdCl3 (1.0 mol%) system at 1123 K. Cyclic voltammograms for Molybdenum (Mo) and Ni electrodes showed the electrodeposition/dissolution of metallic Nd and the formation/dissolution of Nd–Ni alloys, respectively. The equilibrium potential of Nd3+/Nd was determined at 0.27 V (vs. Ca2+/Ca) by open-circuit potentiometry for a Mo electrode. The potentials of 0.48, 0.68, and 0.95 V, corresponding to the two-phase coexisting states of (NdNi2 + NdNi3), (NdNi3 + NdNi5), and (NdNi5 + Ni), respectively, were confirmed using energy-dispersive X-ray spectroscopy and X-ray diffraction of the Ni electrode electrolyzed samples. The optimum electrolysis conditions for the Nd and Dysprosium (Dy) separation were discussed, and the standard Gibbs energies of formation were calculated for Nd–Ni alloys.
Lithium-Ion Diagnostics: The First Quantitative In-Operando Technique for Diagnosing Lithium Ion Battery Degradation Modes under Load with Realistic Thermal Boundary Conditions
Authors: Prosser Ryan , Offer Gregory , Patel Yatish
Published: March 2021

A diagnostic technique capable of quantitatively estimating degradation modes in-operando, including loss of lithium inventory and loss of active material, which operates under charge and discharge loads with realistic thermal boundary conditions is presented for the first time. The technique uses a zero-dimensional heat generation model with only three parameters requiring estimation, a simple heat transfer model, and requires just three temperature measurements per cell, voltage and current. The technique has been demonstrated to work for pouch cells with tab cooling and a constant coolant temperature and for charge and discharge rates of C/2, 1C and 2C. Compared to state-of-the-art open circuit voltage (OCV) model methods, the technique predicts electrode capacities and offset of a fresh cell with accuracies of 3% and 6% respectively. Further the technique has been shown to predict loss of lithium and loss of active material in the positive and negative electrodes with accuracies of 0.18%, 0.22% and 1.99% respectively. The technique can therefore provide information of the same quality as the current state-of-the-art techniques but works under application relevant conditions and due to its simplicity is suitable for implementation on-line in a battery management system (BMS).
RF‐Motion: A Device‐Free RF‐Based Human Motion Recognition System
Authors: Zhao Jumin , Zhou Jianyi , Yao Yuxuan , Li Deng-ao , Gao Liye
Published: March 2021

In recent years, human motion recognition, as an important application of the intelligent perception of the Internet of Things, has received extensive attention. Many applications benefit from motion recognition, such as motion monitoring, elderly fall detection, and somatosensory games. Several existing RF‐based motion recognition systems are susceptible to multipath effects in complex environments, resulting in lower recognition accuracy and difficulty in extending to other scenarios. To address this challenge, we propose RF‐Motion, a device‐free commercial off‐the‐shelf (COTS) RFID‐based human motion recognition system that can detect human motion in complex multipath environments such as indoor environments. And when the environment changes, RF‐Motion still has high recognition accuracy, even without retraining. In addition, we use data slicing to solve the problem of discontinuity in the time domain of RFID communication and then use the synthetic aperture (SAR) algorithm to obtain the fingerprint feature matrix corresponding to each motion. Finally, the dynamic time warping (DTW) algorithm is used to match the prior motion fingerprint database to complete the motion recognition. Experiments show that RF‐Motion can achieve up to 90% accuracy for human motion recognition in an indoor environment, and when the environment changes, it can still reach a minimum accuracy of 87%.
Cost Optimization of Two-Dimensional Warranty Products under Preventive Maintenance
Authors: Wang Qian , Cheng Zhonghua , Gan Qintao , Bai Yongsheng , Zhang Jianqing
Published: March 2021

Aiming to reduce the warranty cost, we put forward a new warranty strategy of two-dimensional (2D) warranty products. In this strategy, the incomplete preventive maintenance and minimal repair are proposed where the preventive maintenance is further divided by the degree of maintenance, and all other failures are repaired minimally. Preventive maintenance of different degree is put forward by the manufacturer and the user, respectively, and the repair factor is used to distinguish the different degree of maintenance. We establish model of warranty cost based on reliability theory and propose a method to solve the model. Finally, the validity of this model is proved by a numerical example, and the sensitivity analysis is carried out.
Urological Tract Infection with Candida Bezoars in a Woman with Diabetes Type 2
Authors: Van Daele Astrid , Schurmans Johan , Van Reusel Raf
Published: March 2021

The aim of this report is to describe a case of fungal bezoar obstruction of the kidney and our experience in managing it endoscopically. A 61-year-old woman presented with flank pain. On CT scan, a proximal stone and secondary dilatation was seen. After placing a DJ stent and administering antibiotics, there was persistent pain, sickness, and kidney dilatation on CT scan. URS showed soft tissue bezoars surrounding the stent and the stone. We managed to remove all the fungal balls mechanically and endoscopically. This report showed that endoscopic removal of the bezoars is a good alternative for antifungal installation.
Combined Auxiliary Networks and Bird’s Eye View Method for Real-Time Multicategory Object Recognition
Authors: Gong Zhangpeng , Wei Luansu , Wang Guoye , Xu Dongxin , Ge Chang
Published: March 2021

Object recognition based on LIDAR data is crucial in automotive driving and is the subject of extensive research. However, the lack of accuracy and stability in complex environments obstructs the practical application of real-time recognition algorithms. In this study, we proposed a new real-time network for multicategory object recognition. The manually extracted bird’s eye view (BEV) features were adopted to replace the resource-consuming 3D convolutional operation. Besides the subject network, we designed two auxiliary networks to help the network learn the pointwise features and boxwise features, aiming to improve the category and bounding boxes’ accuracy. The KITTI dataset was adopted to train and validate the proposed network. Experimental results showed that, for hard mode, the total average precision (AP) of the category reached 97.4%. For an intersection over a union threshold of 0.5 and 0.7, the total AP of regression reached 93.2% and 85.5%; especially, the AP of car’s regression reached 95.7% and 92.2%. The proposed network also showed consistent performance in the Apollo dataset with a processing duration of 37 ms. The proposed network exhibits stable and robust object recognition performance in complex environments (multiobject, unordered objects, and multicategory). And it shows sensitivity to occlusion of the LIDAR system and insensitivity to close large objects. The proposed multifunction method simultaneously achieves real-time operation, high accuracy, and stable performance, indicating its great potential value in practical application.
Experimental Study on Thermal Expansion Behavior of Concrete under Three‐Dimensional Stress
Authors: Yu Zhipeng , Zhang Fan , Ma Xiao , Yang Fujian , Hu Dawei , Zhou Hui
Published: March 2021

Concrete is widely used in underground engineering and bears three‐dimensional stress transmitted by overlying load. When a fire occurs, the thermal expansion of concrete structure under such stress state is different from that under stress‐free state. For this purpose, a self‐developed real‐time high‐temperature true triaxial test system was applied to investigate the thermal expansion behavior of concrete under three‐dimensional stress state. The thermal expansion strain of concrete under the three‐dimensional stress undergoes strain increasing and strain stabilizing stages. At 600°C, the maximum thermal expansion strain of concrete under the three‐dimensional stress is 0.75%. The average coefficient of thermal expansion of concrete under three‐dimensional stress condition was then calculated, and its value reaches the minimum of 8.68 × 10−6/°C at 200°C and the maximum of 13.41 × 10−6/°C at 500°C. Comparing the coefficient of thermal expansion of concrete under stress‐free condition given by Eurocode, it is found that the three‐dimensional stress has an obvious restraint on the thermal expansion of concrete. The research results can provide theoretical basis for the stability analysis of underground engineering concrete structures under high‐temperature environment.
Evaluation of Clinical and Histological Outcomes of Adipose-Derived Mesenchymal Stem Cells in a Rabbit Corneal Alkali Burn Model
Authors: Almaliotis Diamantis , Thomas Angelos , Komnenou Anastasia , Gounari Eleni , Almpanidou Stavroula , Siempis Thomas , Papaioannou Nikolaos , Koliakos Georgios , Papakonstantinou Eleni , Sotiropulos Konstadinos , Karampatakis Vasileios
Published: March 2021

To assess effects of adipose-derived mesenchymal stem cells (AMSCs) in corneal alkali injuries in an experimental animal model. Twenty white New Zealand rabbits were included in the study. The animal models were randomly divided into 2 groups. Rabbits in the AMSC group (

n
=
10

) received an intrastromal, a subconjunctival injection, and topical instillation of 0.5 ml totally of phosphate-buffered saline (PBS) containing

2
×

10

6

AMSCs. In the control group (

n
=
10

), rabbits received only 0.5 ml of PBS using the same methods. A masked investigator measured the corneal sensation, anterior chamber Inflammation (ACI), and conjunctival congestion. Additionally, a blind histological and immunohistochemical evaluation was made. In the AMSC group, the central corneal sensation was increased whereas ACI and conjunctival congestion were reduced compared to the control group in the 28 days of follow-up (

p
<
0.05

). A statistically significant difference (

p
<
0.05

) was noted between the two groups as recorded in the above parameters. Histological analysis showed that pathological vascularization was markedly reduced in the AMSC group which was consistent with the absence of factor VIII in the immunohistochemistry sections. There is a trend towards improved clinical outcomes including corneal sensation as well as acceleration in the restoration of normal corneal architecture in corneal alkali burns treated with AMSCs, results that support the need for further research in the field.
Dynamics of a Delayed Interactive Model Applied to Information Dissemination in Social Networks
Authors: Zhang Yaming , Liu Fei , Koura Yaya H. , Su Yanyuan
Published: March 2021

Reducing fake news and rumor propagation through social media may be challenging to achieve when dealing with sensible contents and communities with free access to online shared resources. Controlling rumor dissemination and promoting true news are the main techniques used to strangle false information that may result in dramatic effect on human wellbeing in an open or closed environment. In this article, we studied a predator-prey model with constant delay in both predator and prey equations and applied the proposed model to the underlying relationship between the existing rumor propagating through social media and the related authoritative information containing the truth broadcast to reduce the respective rumor negative effect on the targeted community. We showed that the proposed system was very responsive to small perturbations and exhibited complex dynamical behavior around the steady-state equilibrium when interaction occurs and delay is applied, considering the controlled situations. Numerical results suggested applying relatively small delay, which represents the ideal time to publish the related propagating rumor curative content to reduce its diffusion speed and promote the truth.
Genetic Feature Fusion for Object Skeleton Detection
Authors: Qiao Yang , Tian Yunjie , Liu Yue , Jiao Jianbin
Published: March 2021

Object skeleton detection requires the convolutional neural networks to recognize objects and their parts in the cluttered background, overcome the image definition degradation brought by the pooling layers, and predict the location of skeleton pixels in different scale granularity. Most existing object skeleton detection methods take great efforts into the designing of side-output networks for multiscale feature fusion. Despite the great progress achieved by them, there are still many problems that hinder the development of object skeleton detection, such as the manually designed network is labor-intensive and the network initialization depends on models pretrained on large-scale datasets. To alleviate these issues, we propose a genetic NAS method to automatically search on a newly designed architecture search space for adaptive multiscale feature fusion. Furthermore, we introduce a symmetric encoder-decoder search space based on reversing the VGG network, in which the decoder can reuse the ImageNet pretrained model of VGG. The searched networks improve the performance of the state-of-the-art methods on commonly used skeleton detection benchmarks, which proves the efficacy of our method.
Long-Term Surveillance and Laparoscopic Management of Zinner Syndrome
Authors: Kelly Niall P. , Fuentes-Bonachera Adrian , Shields William P. , Cullen Ivor M. , Daly Padraig J.
Published: March 2021

Zinner syndrome was first described in 1914 and represents the triad of unilateral renal agenesis and ipsilateral seminal vesicle cyst and ipsilateral ejaculatory duct obstruction. Seminal vesicle cysts are often asymptomatic but can also present with pain, haematospermia, or other lower urinary tract symptoms. Treatment strategies include observation and surgical excision. We present the laparoscopic management of an enlarged seminal vesicle cyst, consistent with Zinner syndrome, 14 years after the initial diagnosis. A 58-year-old male patient was diagnosed with a left-sided seminal vesicle cyst while undergoing assessment for renal transplant due to progressively worsening renal function in his solitary right kidney. The otherwise asymptomatic cyst enlarged from the time of initial diagnosis in 2004 (

11.3
 
cm
×
9.7
 
cm
×
13.1
 
cm

) to nearly double the size in 2018 (

12.8
 
cm
×
11.9
 
cm
×
14.2
 
cm

). This cyst size ultimately precluded renal transplant, and the patient was referred for excision. Laparoscopic excision of the cyst was performed, histopathology confirmed seminal vesicle cyst tissue, and there has been no recurrence of the cyst to date. The patient remains active on the renal transplant waitlist. Zinner syndrome is a rare syndrome, with the seminal vesicle cysts being managed by observation or surgical excision. We report the longest documented observation of a seminal vesicle cyst, culminating in a safe and successful laparoscopic excision.
Analysis of e‐Commerce Characteristics Based on Edge Algorithm and COX Model
Authors: Zuo Jinzhong
Published: March 2021

With the rapid development of C2C (consumer to consumer) e‐commerce transactions in China, the problem of information asymmetry in C2C e‐commerce transactions is becoming more and more obvious. This paper analyzes the specific performance and influence of information asymmetry in C2C e‐commerce transactions and then proposes a strategy to eliminate information asymmetry in C2C e‐commerce transactions. Based on the perspective of information asymmetry, C2C e‐commerce is taken as the research object, and the research methods such as literature analysis method, qualitative analysis method, and case analysis method are comprehensively used to explore the C2C e‐commerce supervision problem in China under the information asymmetry environment. The reason and countermeasures. Secondly, it analyzes the e‐commerce government supervision theory in detail and studies the definition, content, and principle of e‐commerce government supervision, the necessity of e‐commerce government supervision, and the main forms of e‐commerce government supervision in China. The status of China’s e‐commerce supervision is elaborated, including the question of “who is going to supervise,” “who is supervising,” and “how to supervise.” Aiming at the problems of imperfect legal system in China’s e‐commerce supervision, lack of cross‐departmental coordination mechanism, and difficulty in investigation and evidence collection of e‐commerce illegal behavior, we put forward targeted and operational policy recommendations.
Synthesis and Biological Evaluation of Novel Isoxazole‐Amide Analogues as Anticancer and Antioxidant Agents
Authors: Eid Ahmad M. , Hawash Mohammed , Amer Johnny , Jarrar Abdullah , Qadri Samira , Alnimer Iman , Sharaf Aya , Zalmoot Raya , Hammoudie Osama , Hameedi Saba , Mousa Ahmed
Published: March 2021

Cancer now is one of the leading causes of mortality in the world. There has been a lot of effort to discover new anticarcinogenic agents that allow treatment with fewer side effects. A series of isoxazole‐carboxamide derivatives (2a–2g) were synthesised and evaluated for their cytotoxic activity against breast (MCF‐7), cervical (HeLa), and liver (Hep3B) cancer cell lines and their antioxidant activity in the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assay. The results showed that 2d and 2e were the most active compounds against Hep3B cells, with a half‐maximal inhibitory concentration (IC50) of around 23 μg/ml; 2d showed the highest activity against HeLa cells, with an IC50 15.48 μg/ml. However, 2a had the lowest IC50 (39.80 μg/ml) against MCF‐7 cells. By contrast, compound 2g was inactive against all cancer cell lines, with IC50 values >400 μg/ml. Both 2d and 2e reduced Hep3B secretion of alpha‐fetoprotein (to 1829.33 ± 65.91 ng/ml and 1758.66 ± 54.04 ng/ml, respectively). Furthermore, in cell cycle analysis, 2d and 2e induced a delay in the G2/M phase of 18.07%, which is similar to the doxorubicin positive control. Moreover, 2d and 2e reduced the necrosis rate of Hep3B threefold and instead shifted the cells to apoptosis. Our results indicate that 2d and 2e have potent and promising anticancer activity. However, compound 2a was the most active as antioxidant agent (IC50 = 7.8 ± 1.21 μg/ml) compared with Trolox as a positive control (IC50 2.75 μg/ml).
LSR Promotes Cell Proliferation and Invasion in Lung Cancer
Authors: Zhang Min , Ma Cui
Published: March 2021

The lipolysis-stimulated lipoprotein receptor (LSR) displays an important regulatory role in cancer. However, the association between LSR and lung cancer is still elusive. Here, the candidate oncogene LSR on Ch.9q was obtained and assessed by bioinformatics analysis of The Cancer Genome Atlas (TCGA) dataset of lung cancer. We conducted clinical pathology and survival analysis based on the lung cancer database. We assessed the biological effects of LSR in lung cancer cells on cell proliferation. Our data indicated that LSR was upregulated in lung cancer cells. Meanwhile, LSR was identified in this study to be a poor prognostic factor, and its high expression exhibited relations with grades, stages, and nodal metastasis status. Using in vitro analysis, our data revealed that LSR could promote lung cancer progression by regulating cell proliferation, migration, and invasion. In our study, our data demonstrated that LSR was a tumor promoter for lung cancer and was a potential biomarker and target for lung cancer prognosis and treatment.
Research on a Self-Coupling PID Control Strategy for a ZVS Phase-Shift Full-Bridge Converter
Authors: Sun Haidong , Liu Cheng , Zhang Hao , Cheng Yanming , Qu Yongyin
Published: March 2021

As an important part of the high-frequency switching power supply, the control accuracy of the phase-shift full-bridge converter directly affects the efficiency of the switching power supply. To improve the stability and antidisturbance ability of phase-shift control systems, this article presents a dual closed-loop control system based on Self-Coupling PID (SC-PID) control and applies the SC-PID control strategy to the voltage control of the phase-shift full-bridge converter. To begin with, in response to the contradiction of traditional PID, SC-PID breaks the limitation of PID control by introducing a new control idea instead of weighted summation of each gain, which fundamentally solves the contradiction between overshoot and rapidity. Then, using the dimension attributes between gains to develop new tuning rules to solve the system load disturbance, output voltage deviation from the reference value, and other problems, the purpose is to ensure the stability of the output voltage and improve the control effect. At the same time, the stability of the whole control system is analyzed in the complex frequency domain. Finally, with the same main circuit and parameters, three types of controllers are built separately, and using MATLAB for simulation comparison, the simulation results show that the control system based on SC-PID has better steady-state accuracy, faster response, and better robustness, which proves the feasibility of the SC-PID control idea.
Methods Used in Smoking Cessation and Reduction Attempts: Findings from Help-Seeking Smokers
Authors: Lund Marianne , Kvaavik Elisabeth , Mohamed Haniki
Published: March 2021

In addition to traditional smoking cessation methods like nicotine replacement therapy (NRT), new methods such as mobile applications and e-cigarettes have been added to the toolbox. The purpose of this study was to examine which methods smokers currently use in quit or reduction attempts and map characteristics of users of the various methods. In this study, participants were smokers who visited a website or called a quit line for smoking cessation and who were currently in quit or reduction attempts (N = 740). Data were collected in Norway in 2013–2017 through a web survey. Most smokers were currently trying to quit, and the most frequently used methods were a smoking cessation app for mobile phones, nicotine replacement therapies (NRTs), and e-cigarettes. Logistic regression analyses identified older daily smokers with high cigarette consumption as NRT users, while the users of a cessation app were younger females. The use of e-cigarettes was associated with older, low educated smokers with low cigarette consumption. The use of the mobile phone app was associated with having made several recent quit attempts. The study provides insight into help-seeking smokers’ preferences for smoking cessation methods and user characteristics. This knowledge is relevant for further work in smoking cessation planning and policies.
A Fully Adaptively Secure Threshold Signature Scheme Based on Dual-Form Signatures Technology
Authors: Gan Yuanju
Published: March 2021

In

t
,
n

threshold signature schemes, any subset of

t

participants out of

n

can produce a valid signature, but any fewer than

t

participants cannot. Meanwhile, a threshold signature scheme should remain robust and unforgeable against up to

t
−
1

corrupted participants. This nonforgeability property is that even an adversary breaking into up to

t
−
1

participants should be unable to generate signatures on its own. Existential unforgeability against adaptive chosen message attacks is widely considered as a standard security notion for digital signature, and threshold signature should also follow this accordingly. However, there are two special attack models in a threshold signature scheme: one is the static corruption attack and the other is the adaptive corruption attack. Since the adaptive corruption model appears to better capture real threats, designing and proving threshold signature schemes secure in the adaptive corruption model has been focused on in recent years. If a threshold signature is secure under adaptive chosen message attack and adaptive corruption attack, we say it is fully adaptively secure. In this paper, based on the dual pairing vector spaces technology, we construct a threshold signature scheme and use Gerbush et al.’s dual-form signatures technology to prove our scheme, which is fully adaptively secure in the standard model, and then compare it to other schemes in terms of the efficiency and computation.
Tetrandrine Ameliorates Myocardial Ischemia Reperfusion Injury through miR‐202‐5p/TRPV2
Authors: Zhao Wei , Wu Youyang , Ye Fanhao , Huang Shiwei , Chen Hao , Zhou Rui , Jiang Wenbing
Published: March 2021

Objective. This study is aimed at investigating the therapeutic effects of tetrandrine (Tet) on myocardial ischemia reperfusion (I/R) injury and probe into underlying molecular mechanism. Methods. H9C2 cells were divided into hypoxia/oxygenation (H/R) group, H/R+Tet group, H/R+Tet+negative control (NC) group, and H/R+Tet+miR‐202‐5p inhibitor group. RT‐qPCR was utilized to monitor miR‐202‐5p and TRPV2 expression, and TRPV2 protein expression was detected via western blot and immunohistochemistry in H9C2 cells. Cardiomyocyte apoptosis was evaluated through detection of apoptosis‐related markers and flow cytometry. Furthermore, myocardial enzyme levels were detected by ELISA. Rats were randomly separated into sham operation group, I/R group, I/R+Tet group (50 mg/kg), I/R+Tet+NC group, and I/R+Tet+miR‐202‐5p inhibitor group. miR‐202‐5p and TRPV2 mRNA expression was assessed by RT‐qPCR. TRPV2 protein expression was detected through western blot and immunohistochemistry in myocardial tissues. Apoptotic levels were assessed via apoptosis‐related proteins and TUNEL. Pathological changes were observed by H&E staining. Myocardial infarction size was examined by Evans blue‐TCC staining. Results. Abnormally expressed miR‐202‐5p as well as TRPV2 was found in H/R H9C2 cells and myocardial tissues of I/R rats, which was ameliorated following Tet treatment. Tet treatment significantly suppressed H/R‐ or I/R‐induced cardiomyocyte apoptosis. ELISA results showed that CK‐MB and LDH levels were lowered by Tet treatment in H/R H9C2 cells and serum of I/R rats. H&E staining indicated that Tet reduced myocardial injury in I/R rats. Also, myocardial infarction size was lowered by Tet treatment. The treatment effects of Tet were altered following cotreatment with miR‐202‐5p inhibitor. Conclusion. Our findings revealed that Tet may ameliorate myocardial I/R damage via targeting the miR‐202‐5p/TRPV2 axis.
Acute Kidney Injury following Cardiopulmonary Bypass: A Challenging Picture
Authors: Liu Dianxiao , Liu Baohui , Liang Zhenxing , Yang Zhi , Ma Fangjian , Yang Yang , Hu Wei
Published: March 2021

Recent studies have recognized several risk factors for cardiopulmonary bypass‐ (CPB‐) associated acute kidney injury (AKI). However, the lack of early biomarkers for AKI prevents practitioners from intervening in a timely manner. We reviewed the literature with the aim of improving our understanding of the risk factors for CPB‐associated AKI, which may increase our ability to prevent or improve this condition. Some novel early biomarkers for AKI have been introduced. In particular, a combinational use of these biomarkers would be helpful to improve clinical outcomes. Furthermore, we discuss several interventions that are aimed at managing CPB‐associated AKI, may increase the effect of renal replacement therapy (RRT), and may contribute to preventing CPB‐associated AKI. Collectively, the conclusions of this paper are limited by the availability of clinical trial evidence and conflicting definitions of AKI. A guideline is urgently needed for CPB‐associated AKI.
Static and Dynamic Tensile Mechanical Behavior of Polyvinyl Chloride Elastomers with Different Shore Hardness
Authors: Lei Jingfa , Xuan Yan , Liu Tao , Duan Feiya , Wei Zhan , Lu Chen
Published: March 2021

An experiment on the static and dynamic tensile mechanical properties of polyvinyl chloride (PVC) elastomers is conducted using an Instron‐5943 universal testing machine and an improved Split Hopkinson Tensile Bar to study the dynamic tensile mechanical properties of PVC elastomer materials. The stress‐strain curves of PVC materials with three types of Shore hardness (57A, 52A, and 47A) under the strain rates of 0.1 s−1 and 400 ∼ 1800 s−1 are obtained. Results show that the mechanical behavior of PVC elastomer materials with different Shore hardness has remarkable linear elastic characteristics under the action of quasistatic tensile load. It has substantial sensitivity to strain rate and viscoelastic mechanical characteristics under the action of dynamic tensile load. The Zhu–Wang–Tang nonlinear viscoelastic constitutive model is used to characterize the viscoelastic mechanical characteristics with small error. This paper can provide theoretical model and method support for the design, development, production, and reliability analysis of PVC elastomers and other soft polymer materials.
Enseñanzas de la pandemia para enseñar negocios
Authors: Saldaña Rosas Alejandro J.
Published: March 2021

En este trabajo se exponen algunas ideas-hipótesis en torno a las enseñanzas derivadas de la pandemia de COVID-19 para las escuelas de negocios. En particular, se propone que en la curricula de las escuelas de negocios y de administración de empresas se incluyan reflexiones y formación en torno a cinco tópicos: i) la revaloración de lo público; ii) la reivindicación del trabajo sobre el capital; iii) formación en economía social y solidaria; iv) reflexión sobre el extractivismo de datos y el capitalismo de vigilancia; v) reflexión sobre el modelo capitalista de desarrollo y las enfermedades zoonóticas.