bluuebunny/crossref_metadata_2025 huggingface dataset:
Travel Choice Behavior Model Based on Mental Accounting of Travel Time and Cost
Authors: Liu Shixu , Zhu Jianchao , Easa Said M. , Guo Lidan , Wang Shuyu , Wang Haoyu , Xu Yijian
Published: December 2021

This paper analyzes the utility calculation principle of travelers from the perspective of mental accounting and proposes a travel choice behavior model that considers travel time and cost (MA-TC model). Then, a questionnaire is designed to analyze the results of the travel choice under different decision-making scenarios. Model parameters are estimated using nonlinear regression, and the utility calculation principles are developed under different hypothetical scenarios. Then, new expressions for the utility function under deterministic and risky conditions are presented. For verification, the nonlinear correlation coefficient and hit rate are used to compare the proposed MA-TC model with the other two models: (1) the classical prospect theory with travel time and cost (PT-TC model) and (2) mental accounting based on the original hedonic editing criterion (MA-HE model). The results show that model parameters under deterministic and risky conditions are pretty different. In the deterministic case, travelers have similar sensitivity to the change in gain and loss of travel time and cost. The prediction accuracy of the MA-TC model is 3% lower than the PT-TC model and 6% higher than the MA-HE model. Under risky conditions, travelers are more sensitive to the change in loss than to the change in gain. Additionally, travelers tend to overestimate small probabilities and underestimate high probabilities when losing more than when gaining. The prediction accuracy of the MA-TC model is 2% higher than the PT-TC model and 6% higher than the MA-HE model.
Comparison of Paraquat Herbicide Removal from Aqueous Solutions using Nanoscale Zero-Valent Iron-Pumice/Diatomite Composites
Authors: Khodabakhshi Abbas , Mohammadi-Moghadam Fazel , Amin Mohammad Mehdi , Hamati Sara , Hayarian Shakila
Published: December 2021

Paraquat is the most important herbicide of the bipyridyl group. The aim of the present study was to compare the removal of paraquat herbicide from aqueous solutions using nanoscale zero-valent iron-pumice/diatomite composites. In this study, nZVI was supported with diatomite and pumice. Scanning electron microscopy (SEM) analysis, X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectrometry (FTIR), and specific surface area tests (BET) were used to evaluate the properties of nanoadsorbents. The residual concentration of paraquat in aqueous solution was detected by high-performance liquid chromatography (HPLC). Then, the effects of different variables including the pollutant concentration, contact time, temperature, adsorbents (D-nZVI and P-nZVI) dose, and pH, were investigated in a lab scale batch system. The results showed that the optimal pH for both processes was 3.74. In optimal conditions, the efficiencies of D-nZVI and P-nZVI were 92.76% and 85.28%, respectively. In addition, isotherm and adsorption kinetics studies indicated that P-nZVI follows the Langmuir and Freundlich isotherm models, and D-nZVI follows the Langmuir isotherm model, and both processes follow pseudo-second-order kinetics. The results indicated that the synthesized nanoparticles were suitable for removing paraquat from aqueous solutions. Both adsorbents were found to be very effective in removing similar compounds at ambient temperature in a short time.
Exceptional Sets for Sums of Prime Cubes in Short Interval
Authors: Chen Gongrui
Published: December 2021

Let

E

N
,
X

denote the number of even integers

n

, with

N
−
X
≤
n
≤
N

, such that

n

cannot be written as

n
=

p
1
3

+
⋯
+

p
8
3

. We prove that if

X
>

N

1
/

36

+
ɛ

, then

E

N
,
X

=
o

X

.
An Efficient and Secure Malicious User Detection Scheme Based on Reputation Mechanism for Mobile Crowdsensing VANET
Authors: Wang Zhihua , Liu Jiahao , Guo Chaoqi , Hu Shuailiang , Wang Yongjian , Yang Xiaolong
Published: December 2021

With the increasing development of wireless communication technology and Vehicular Ad hoc Network (VANET), as well as the continuous popularization of various sensors, Mobile Crowdsensing (MCS) paradigm has been widely concerned in the field of transportation. As a currently popular data sensing way, it mainly relies on wireless sensing devices to complete large‐scale and complex sensing tasks. However, since vehicles are highly mobile in this scenario and the sensing system is open, that is, any vehicle equipped with sensing device can join the system, the credibility of all participating vehicles cannot be guaranteed. In addition, malicious users will upload false data in the sensing system, which makes the sensing data not meet the needs of the sensing tasks and will threaten traffic safety in some serious cases. There are many solutions to the above problems, such as cryptography, incentive mechanism, and reputation mechanisms. Unfortunately, although these schemes guaranteed the credibility of users, they did not give much thought to the reliability of data. In addition, some schemes brought a lot of overhead, some used a centralized server management architecture, and some were not suitable for the scenario of VANET. Therefore, this paper firstly proposes the MCS‐VANET architecture‐based blockchain, which consists of participating vehicles (PVs), road side units (RSUs), cloud server (CS), and the blockchain (BC), and then designs a malicious user detection scheme composed of three phases. In the data collecting phase, to reduce the data uploading overhead, data aggregation and machine learning technologies are combined by fully considering the historical reputation value of PVs, and the proportion of data uploading is determined based on the historical data quality evaluation result of PVs. In the data quality evaluation phase, a new reputation computational model is proposed to effectively evaluate the sensing data, which contains four indicators: the reputation history of PVs, the data unbiasedness, the leadership of PVs, and the spatial force of PVs. In the reputation updating phase, to achieve the effective change of reputation values, thelogisticmodel function curve is introduced and the result of the reputation updating is stored in the blockchain for security publicity. Finally, on real datasets, the feasibility and effectiveness of our proposed scheme are demonstrated through the experimental simulation and security analysis. Compared with existing schemes, the proposed scheme not only reduces the cost of data uploading but also has better performance.
Reversible Information of Encrypted Image Based on Feature Difference Detection and Wavelet Transform
Authors: Ding Yongsheng , Wei Yunbo , Zhang Shuisheng , Yu Shihang
Published: December 2021

Aiming at the shortcomings of the existing lossless digital watermarking algorithm based on frequency domain in reversibility and embedding capacity, this study proposes a lossless digital image watermarking algorithm based on fractional wavelet transform, which is used for large-capacity reversible information hiding of images. First, the image is transformed by LeGall5/3 fractional wavelet, and then, the watermark is embedded in the high-frequency subband by the histogram shift method. In order to obtain maximum embedding capacity and reduce image distortion, the methods of selecting embedding parameters and stopping parameters are proposed, respectively. At the same time, in order to prevent overflow and reduce additional information, a new method of generating position map is proposed. The experimental results show that Lena is the result of multilayer embedding based on the algorithm in this study. In order to better observe the distortion phenomenon and enlarge the image, the Lena test image is the watermark image obtained after two and three layers of embedding, and its embedding capacity can be 2.7 bpp. It is proved that wavelet transform is suitable for encrypted images to implement covert communication.
Multiscenario-Based Train Headway Analysis under Virtual Coupling System
Authors: Pan Jinyi , Peng Qiyuan , Zhan Shuguang , Bai Jiaqi
Published: December 2021

Chinese high-speed railway has implemented large-scale network operation with an urgent need for capacity improvement. The concept of virtual coupling seems to be a promising solution that provides a new operational scenario for high-speed railway, where trains are formed into a cooperative convoy and run synchronously with small train headways. The train-following principles under the virtual coupling signalling are quite different from those under conventional train control systems. Therefore, train headway analysis for different operational scenarios should be carried out to ensure railway safety and evaluate capacity benefits brought by virtual coupling. This paper proposes a potential virtual coupling architecture with reference to ETCS/ERTMS specifications. We compare blocking time models under different train control systems, and eight typical train-following scenarios are investigated for virtual coupling, including train arrival and departure cases. A detailed multiscenario-based train headway analysis is provided based on the microscopic infrastructure of the station and technological characteristics of virtual coupling. All computational outcomes are based on the train dynamic motion model. A comparative analysis of train headways under virtual coupling and CTCS-3 is provided in the case study. Results show that train headways can be substantially reduced under virtual coupling and are related to the station infrastructure layout.
Research on Energy Efficiency Management of Forklift Based on Improved YOLOv5 Algorithm
Authors: Li Zhenyu , Lu Ke , Zhang Yanhui , Li Zongwei , Liu Jia-Bao
Published: December 2021

As an important tool for loading, unloading, and distributing palletized goods, forklifts are widely used in different links of industrial production process. However, due to the rapid increase in the types and quantities of goods, item statistics have become a major bottleneck in production. Based on machine vision, the paper proposes a method to count the amount of goods loaded and unloaded within the working time limit to analyze the efficiency of the forklift. The proposed method includes the data preprocessing section and the object detection section. In the data preprocessing section, through operations such as framing and clustering the collected video data and using the improved image hash algorithm to remove similar images, a new dataset of forklift goods was built. In the object detection section, the attention mechanism and the replacement network layer were used to improve the performance of YOLOv5. The experimented results showed that, compared with the original YOLOv5 model, the improved model is lighter in size and faster in detection speed without loss of detection precision, which could also meet the requirements for real-time statistics on the operation efficiency of forklifts.
Therapeutic Effect of Cervical Cerclage on Cervical Insufficiency during Pregnancy Analyzed by Magnetic Resonance Image under Neural Network Algorithm
Authors: Liu Yongjuan , Tan Yongpan , Liu Rongxia , Ye Xuekui , Wang Lina , Cui Wei , Lu Dan , Guo Jing , Chu Dongmei
Published: December 2021

Objective. This research was developed to investigate the effect of magnetic resonance imaging (MRI) analysis based on neural network algorithm for cervical ligation in the treatment of cervical insufficiency. Methods. 44 patients who were suspected to be pregnant with cervical insufficiency and needed cervical ligation were selected. MR imaging analysis was performed before cervical ligation. MR images were analyzed based on the back propagation neural network (BPNN) algorithm, and patients were randomly divided into experimental group and control group. Preoperative MRI analysis was performed in the experimental group, while simple transvaginal ultrasonography was used to diagnose cervical insufficiency in the control group. Then, postoperative fetal preservation time, vaginal bleeding rate, and infection rate within one week after surgery were compared between the two groups. Results. Based on experience and experimental testing, the relevant parameters were set as follows. The number of particles n = 50, the inertia weight ω = 0.9, and c1 = c2 = 2. The weight range of the output layer of the neural network was [−1, 1], the target error e = 10−5, and the maximum number of iteration steps was 3,000. Compared with the control group, the experimental group’s postoperative bleeding rate and infection probability were substantially reduced, while the normal delivery rate was substantially increased (

P
<
0.05

). Conclusion. MR image analysis based on neural network algorithm played an important role in cervical cerclage surgery. The image map showed the local anatomy clearly, increasing the success rate of the operation and improving the prognosis of the patient.
Art Product Design and VR User Experience Based on IoT Technology and Visualization System
Authors: Guo Ling , Wang Peng
Published: December 2021

Based on the Internet of Things technology, this paper analyzes the concept and basic characteristics of visualization technology and builds a visualization digital art product information system based on VRML virtual reality technology. This article first explains the background and significance, analyzes the research status at home and abroad, introduces the application of virtual realization technology, and puts forward the technical route and main research content on this basis. After field inspection of art products, the system was analyzed according to the actual situation. After analyzing the needs and goals of the system, the overall structure of the system was proposed. Under the overall framework, this paper designs the system and designs the system’s visualization and real‐time interaction modules. At the same time, combined with VRML technology to realize the visual 3D modeling of virtual art products, we establish the 3D model of the entire art product. Users can choose between role roaming and camera roaming. Finally, we made a summary statement to the full text and looked forward to the application prospects and development trends of information visualization technology in digital art products. During the experiment, by calling the HTC method in the Unity 3D system, this article uses the Unity 3D engine to implement UI scene loading and VR rendering technology optimization and realizes design knowledge through the integration of art product design models and IoT data interactive functions and dynamic loading of scenes. The effect of the model on the quality prediction is analyzed through experiments. The results show that the performance of the former is better than the latter two models, and it has a good performance on unbalanced data processing, which verifies the performance and effectiveness of the algorithm model.
Image Reconstruction from Multiscale Singular Points Based on the Dual-Tree Complex Wavelet Transform
Authors: Liu Sihang , Tremblais Benoit , Carre Phillippe , Zhou Nanrun , Wu Jianhua
Published: December 2021

The representation of an image with several multiscale singular points has been the main concern in image processing. Based on the dual-tree complex wavelet transform (DT-CWT), a new image reconstruction (IR) algorithm from multiscale singular points is proposed. First, the image was transformed by DT-CWT, which provided multiresolution wavelet analysis. Then, accurate multiscale singular points for IR were detected in the DT-CWT domain due to the shift invariance and directional selectivity properties of DT-CWT. Finally, the images were reconstructed from the phases and magnitudes of the multiscale singular points by alternating orthogonal projections between the CT-DWT space and its affine space. Theoretical analysis and experimental results show that the proposed IR algorithm is feasible, efficient, and offers a certain degree of denoising. Furthermore, the proposed IR algorithm outperforms other classical IR algorithms in terms of performance metrics such as peak signal-to-noise ratio, mean squared error, and structural similarity.
Patients with Dipper and Nondipper High-Normal Blood Pressure Were Associated with Left Ventricular Mass
Authors: Xiao Fan-kai , Li Ping , Han Zhan-ying , Jing Li , Hua Shaohua , Zhao Luo-sha
Published: December 2021

Purpose. High-normal blood pressure has been suggested to associate with target organ damage and higher left ventricular mass index (LVMI). Our aim is to find the association between people with high-normal blood pressure and their left ventricular mass index. Materials and Methods. Given a total of 181 people with office blood pressure, 24-hour ambulatory blood pressure monitoring, 35 of them are normotensive (BP < 130/85 mm Hg), and 146 people with high-normal blood pressure (BP 130–139/85–89 mm Hg), divide the high-normal blood pressure group into dipper and nondipper according to their ABPM in 24 hours. All of them were performed with echocardiography to calculate LVMI. Results. After adjusting for potential confounding factors, mean systolic blood pressure (BP) of the nondipper group is (119 + 9) mmHg in 24 h, which is significantly higher (

p

 < 0.05) than in the dipper group (116 + 11) mmHg, indicating the mean systolic BP is associated with the dipper type (

p

 < 0.05); furthermore, the higher nocturnal blood pressure is associated with the nondipper group significantly (

p

 < 0.05), and LVMI ((121 ± 11) g/m2) of the nondipper group is also significantly higher than in the dipper group’s LVMI ((108 ± 12) g/m2) (

p

 < 0.05). The multivariate linear regression analyses revealed significant and independent associations of LVMI with these factors: triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and coefficient of variation of systolic and diastolic blood pressure in 24 hours. Conclusion. After multiple relevant clinical confounding factors were adjusted, patients with dipper and nondipper high-normal blood pressure had higher LVMI. Abnormalities in circadian blood pressure variability may be associated with the left ventricular hypertrophy.
Prediction of Conductive Anomalies Ahead of the Tunnel by the 3D-Resitivity Forward Modeling in the Whole Space
Authors: Hu Daiming , Tezkan Bülent , Yue Mingxin , Yang Xiaodong , Wu Xiaoping , Zhou Guanqun
Published: December 2021

Water inrush in tunneling poses serious harm to safe construction, causing economic losses and casualties. The prediction of water hazards before tunnel excavations becomes an urgent task for governments or enterprises to ensure security. The three-dimensional (3D) direct current (DC) resistivity method is widely used in the forward-probing of tunnels because of its low cost and highly sensitive response to water-bearing structures. However, the different sizes of the tunnel will distort the distribution of the potential field, which causes an inaccurate prediction of water-bearing structures in front of the tunnels. Some studies have pointed out that the tunnel effect must be considered in the quantitative interpretation of the data. However, there is rarely a predicted model considering the tunnel effect to be reported in geophysical literature. We developed a predicted model algorithm by considering the tunnel effect for forward-probing in tunnels. The algorithm is proven to be feasible using a slab analytic model. By simulating a large number of models with different tunnel sizes, we propose an equation, which considers the tunnel effect and can predict the water-bearing structures ahead of the tunnel face. The Monte Carlo method is used to evaluate the quality of the predicted model by simulating and comparing 10,000 random models. The results show that the proposed method is accurate to forecast the water-rich structures with small errors.
A Case of Untreated Myeloid Sarcoma of the Pancreas Head Region: Diagnostic Process of AML Subtyping in an Autoptic Case
Authors: Fukumura Yuki , Taniguchi Gentaro , Koyanagi Ai , Horiuchi Yuki , Ochiai Tomonori , Tabe Yoko , Sano Katsuhiro , Maimaitiaili Yifare , Otsuji Naomi , Ashizawa Karin , Yao Takashi
Published: December 2021

This study describes an autopsy case of pancreatic/peripancreatic myeloid sarcoma in a 70-year-old man, initially presenting with obstructive jaundice. Pathologically, diffuse infiltration of round cells containing atypical nuclei with marked cleavage was observed mainly in the pancreas head, peripancreatic lymph nodes, spleen, bilateral lung, and bone marrow. Immunohistochemically, the tumor cells were negative for CD20, CD79a, CD3, CD5, c-kit, CD34, and TdT and positive for myeloperoxidase, CD33, CD68, and CD163. Flow cytometry of the peripheral blood showed underexpression of CD11c and aberrant expression of CD56 in the monocyte subset. The peripheral blood smear showed an increase in monocytes and atypia in neutrophils and monocytes, as well as enlarged platelets and polychromatic erythroblasts. Hence, it was suggested that the myeloid sarcoma was derived from the acute transformation of chronic myelomonocytic leukemia. Myeloid sarcoma is an extramedullary-mass-forming hematologic malignancy that is difficult to diagnose, especially when the initial presentation is a pancreatic mass. However, early diagnosis is important for appropriate therapy. Although bone marrow examination could not be performed because of the patients’ severe condition, the pathological specimen obtained with autopsy helped subtype the patient’s leukemia. The immunohistochemical features of this case merit attention.
An Effective Solution of the Cube-Root Truly Nonlinear Oscillator: Extended Iteration Procedure
Authors: Haque B. M. Ikramul , Hossain M. M. Ayub
Published: December 2021

The cube-root truly nonlinear oscillator and the inverse cube-root truly nonlinear oscillator are the most meaningful and classical nonlinear ordinary differential equations on behalf of its various applications in science and engineering. Especially, the oscillators are used widely in the study of elastic force, structural dynamics, and elliptic curve cryptography. In this paper, we have applied modified Mickens extended iteration method to solve the cube-root truly nonlinear oscillator, the inverse cube-root truly nonlinear oscillator, and the equation of pendulum. Comparison is made among iteration method, harmonic balance method, He’s amplitude-frequency formulation, He’s homotopy perturbation method, improved harmonic balance method, and homotopy perturbation method. After comparison, we analyze that modified Mickens extended iteration method is more accurate, effective, easy, and straightforward. Also, the comparison of the obtained analytical solutions with the numerical results represented an extraordinary accuracy. The percentage error for the fourth approximate frequency of cube-root truly nonlinear oscillator is 0.006 and the percentage error for the fourth approximate frequency of inverse cube-root truly nonlinear oscillator is 0.12.
College English Online Teaching Model Based on Deep Learning
Authors: Ding Hui , Chen Yajun , Wang Linling
Published: December 2021

In today’s era, online teaching plays an important part in the college English teaching. Deep learning, famous for its ability of imitating the learning process of human brains and obtaining the internal essential features or rules of voice, videos, images, and other data, can be applied to assist and improve the college English online teaching which involves a wide use of those data. Based on the combination of the multilayer neural network model and the k-means clustering algorithm, this paper designs a kind of deep learning method that can be used to assist and improve the college English online teaching. Experiments were designed to test the reliability of this deep learning method. The results show that the optimization algorithm designed in this paper, which can adjust the learning rate, will improve the common probability gradient descent algorithm. Besides, it is proved that the deep learning’s efficiency of the CNN model is significantly higher than that of the MLP model. With the help of this deep learning method, it becomes feasible to apply the technologies related to the artificial intelligence to help teachers deeply analyze and diagnose students’ English learning behavior, replace the teachers in part to answer students’ questions in time, and automatically grade assignments in the process of the college English online teaching. Surveys and exams were then conducted to evaluate the effect of the application of the college English online teaching model based on deep learning on the students’ learning cognition and their academic performance. The results show that the college English online teaching model based on deep learning can stimulate students’ learning motivation and improve their academic performance.
Sphingosine Kinase 1 Plays an Important Role in Atorvastatin-Mediated Anti-Inflammatory Effect against Acute Lung Injury
Authors: Wu Lan , Cheng Yan , Peng Shunxiang , Zhang Wensheng , Zhang Chaoxiong
Published: December 2021

Atorvastatin is a 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) inhibitor and inhibits cholesterol synthesis. Recently, atorvastatin also showed anti-inflammatory effect in acute lung injury, ameliorating pulmonary gas-blood exchanging function. Sphingosine kinase 1 plays a central role in endothelial (EC) cytoskeleton rearrangement and EC barrier integrity regulation. In this study, the role of sphingosine kinase 1 in atorvastatin anti-inflammatory effect against acute lung injury was investigated. Both wild-type (WT) and SphK1-/- mice were challenged with high tidal volume ventilation (40 ml/kg body weight, 65 breathing/min, 4 hours). The acute lung injury was evaluated and the mechanisms were explored. In WT mice, atorvastatin treatment significantly decreased acute lung injury responding to high tidal volume ventilation (HT), including protein, cellular infiltration, and cytokine releasing; comparing to WT mice, SphK1-/- mice showed significantly worsen pulmonary injuries on HT model. Moreover, the atorvastatin-mediated anti-inflammatory effect was diminished in SphK1-/- mice. To further confirm the role of SphK1 in VILI, we then compared the inflammatory response of endothelial cells that were isolated from WT and SphK1-/- mice to cyclic stretching. Similarly, atorvastatin significantly decreased cytokine generation from WT EC responding to cyclic stretching. Atorvastatin also significantly preserved endothelial junction integrity in WT EC against thrombin challenge. However, the inhibitory effect of atorvastatin on cytokine generation induced by cyclic stretching was abolished on SphK1-/- mice EC. The endothelial junction integrity effects of atorvastatin also diminished on SphK1-/- mouse EC. Signal analysis indicated that atorvastatin inhibited JNK activation induced by cyclic stretch. SphK1 knockout also blocked atorvastatin-mediated VE-cadherin junction enhancement. In summary, by inhibition of MAPK activity and maintenance of EC junction homeostasis, SphK1 plays a critical role in atorvastatin-mediated anti-inflammatory effects in both cellular and in vivo model. This study also offers an insight into mechanical stress-mediated acute lung injury and potential therapy in the future.
Location-Dependent Query Processing: Semantic Cache for Real-Time Smart City Analytics
Authors: Hasan Rabia , Shehzad Waseem , Ahmed Ejaz , Khattak Hasan Ali , AlGhamdi Ahmed S. , Alshamrani Sultan S.
Published: December 2021

With the advent of wireless sensor networks and their deep integration with the world have enabled users worldwide to achieve benefits from location-based services through mobile applications, the problems such as low bandwidth, high network traffic, and disconnections issues are normally extracted from mobile services. An efficient database system is required to manage mentioned problems. Our research work finds the probability of user’s next locations. A mobile user (query issuer) changes its position when performing a specific mobile search, where these queries change and repeat the search with the issuer position. Moreover, the query issuer can be static and may perform searches with varying conditions of queries. Data is exchanged with mobile devices and questions that are formulated during searching for query issuer locations. An aim of the research work is achieved through effectively processing of queries in terms of location-dependent, originated by mobile users. Significant studies have been performed in this field in the last two decades. In this paper, our novel approach comprise of usage of semantic caches with the Bayesian networks using a prediction algorithm. Our approach is unique and distinct from the traditional query processing system especially in mobile domain for the prediction of future locations of users. Consequently, a better search is analyzed using the response time of data fetch from the cache.
Extracellular HMGB1 Induced Glomerular Endothelial Cell Injury via TLR4/MyD88 Signaling Pathway in Lupus Nephritis
Authors: Yu Tian , Xiaojuan Feng , Jinxi Liu , Xinyan Miao , Jie Xu , Yuexin Tian , Qingjuan Liu , Wei Zhang , Cunyang Gu , Jie Huang , Lunbi Wu , Hang Zhao , Shuxia Liu , Huifang Guo
Published: December 2021

Previously, our study showed that HMGB1 was significantly elevated in the blood and located in the glomerular endothelium in LN patients. But whether extracellular HMGB1 is involved in the injury of glomerular endothelial cells (GECs) in LN still needs further investigation. Firstly, we detected the levels of SDC-1, VCAM-1, and proteinuria in LN patients and MRL/lpr mice and analyzed their correlations. Then, HMGB1 and TLR4/MyD88 were inhibited to observe the shedding of glycocalyx and injury of GECs in vivo and in vitro. Our results showed that HRGEC injury and SDC-1 shedding played an important role in the increase of permeability and proteinuria formation in LN. Additionally, inhibition of extracellular HMGB1 and/or downstream TLR4/MyD88/NF-κB/p65 signaling pathway also alleviated GEC monolayer permeability, reduced the shedding of the glomerular endothelial glycocalyx, improved the intercellular tight junction and cytoskeletal arrangement, and downregulated the NO level and VCAM-1 expression. These results suggested that extracellular HMGB1 might involve in GEC injury by activating the TLR4/MyD88 signaling pathway in LN, which provided novel insights and potential therapeutic target for the treatment of lupus nephritis.
desafíos de la educación médica en México
Authors: García Luna Martínez José Eduardo Erasmo , Silva Ulibarri Luis Alberto , García Macías Jorge Luis , López Tapia Jesús Daniel , Sandoval Mussi Ana Yolanda , Garza Sáenz Olinda Giselle
Published: December 2021

La educación médica genera impacto en la salud de las poblaciones; formar médicos profesionalizados con capacidad para adaptarse a entornos cambiantes permite comprender con mayor detalle la epidemiología de una comunidad o país y mejorar la salud pública. Dar al estudiante de medicina las herramientas necesarias para proporcionar una atención de calidad puede mejorar la salud de cientos de pacientes. La educación médica está llena de desafíos y se encuentra en una búsqueda continua de excelencia. El modelo educativo actual busca centrarse en las competencias requeridas por los sistemas de salud y educación de México, pero COVID-19 rompió paradigmas y revolucionó la manera en la que se enseña medicina, centrándose en el aprendizaje autorregulado. El mundo está en constante cambio y la educación médica debe evolucionar con el mundo. La tecnología es la herramienta que revoluciona la enseñanza y permite introducir la globalización a las escuelas, aprendiendo así sobre otras culturas y su manera de practicar la medicina. La salud mental de los estudiantes es determinante para evitar la deserción y formar médicos sanos. El integrar condiciones de bienestar a nivel nacional e institucional tendrá un impacto positivo en la vida de los estudiantes, y los ayudará a desempeñarse mejor en el futuro. El reto de la educación médica actualmente es inspirar la formación de médicos capaces de insertarse en un mercado laboral competitivo, sin descuidar la atención al paciente, con habilidades directivas y organizacionales, evitando la sobre-especialización como limitante del desarrollo profesional.
New beginnings in post graduate medical education. Latin American Medical Education Leaders Forum
Authors: Puschel Klaus , Telesco Tai , Grez Marcela , Hoyl Trinidad , Ibañez Luis , Casiro Oscar Casiro
Published: December 2021

Introduction: The consequences of the Covid-19 epidemic have been catastrophic for Latin America in 2021. This study explores experiences, lessons learned, and practice changes during this critical time in post-graduate medical education in Latin America. Methods: A panel of 53 post-graduate medical education leaders from 8 Latin American countries and Canada was invited to participate in the 2021 Latin American Medical Education Leaders Forum to share their experiences, lessons learned, and main educational practice changes given the Covid-19 pandemic scenario. Participants were selected following a snowball technique with the goal of obtaining a diverse group of experts. Small group discussions were conducted by bilingual facilitators based on a semi-structured questionnaire. The plenary session with the main conclusions of each group was recorded and fully transcribed for a thematic analysis using a framework methods approach. Results: Participants´ profiles included 13 experienced clinician-educators, 19 program directors, and 23 deans or organizational representatives. Seven specific themes emerged. They followed a pattern that went from an initial emotional reaction of surprise to a complex collective response. The responses highlighted the value of adaptability, the application of new digital skills, a renovated residents’ protagonism, the strengthening of humanism in medicine, the openness of new perspectives in wellness, and finally, an unresolved challenge of assessment in medical education in a virtual post-pandemic scenario. Conclusion: A diverse panel of medical educators from Latin America and Canada identified changes triggered by the Covid-19 pandemic that could transform postgraduate medical education in the region.
Association of Metabolic Health and Central Obesity with the Risk of Thyroid Cancer: Data from the Korean Genome and Epidemiology Study
Authors: Nguyen Dung N. , Kim Jin Hee , Kim Mi Kyung
Published: December 2021

Background:

It is unknown whether the risk of thyroid cancer differs among metabolically healthy/unhealthy, normal-weight, or obese women. We aimed to assess the association of metabolic health and obesity with thyroid cancer risk.

Methods:

The Korean Genome and Epidemiology Study is a population-based prospective cohort study. Data were obtained from 173,343 participants (age ≥40 years) enrolled from 2004 to 2013. Obese participants were those with body mass index (BMI) ≥25 kg/m2. Participants with abnormalities in three of these indices were considered metabolically unhealthy: triglycerides, blood pressure, high-density lipoprotein cholesterol (HDL-cholesterol), waist circumference (WC), and fasting glucose levels. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for thyroid cancer risk associated with metabolic health and obesity.

Results:

Compared with nonobese women without metabolic abnormalities, metabolically unhealthy women, either normal weight or obese, had an increased risk of thyroid cancer [HR (95% CI) = 1.57 (1.02–2.40) and 1.71 (1.21–2.41), respectively). Significant association was not observed in men. Thyroid cancer risk was higher among nonobese women with high WC [≥85 cm; HR (95% CI) = 1.62 (1.03–2.56)] than in nonobese women with low WC, and in obese women with low HDL-cholesterol [<50 mg/dL; HR (95% CI) = 1.75 (1.26–2.42)] compared with nonobese women with high HDL-cholesterol.

Conclusions:

Metabolically unhealthy women or women with central adiposity may be at an increased thyroid cancer risk despite normal BMI.

Impact:

This study suggests that women with central obesity and metabolic abnormality despite normal BMI may constitute a target group for thyroid cancer prevention and control programs.
Hypoxia Drives Centrosome Amplification in Cancer Cells via HIF1α-dependent Induction of Polo-Like Kinase 4
Authors: Mittal Karuna , Kaur Jaspreet , Sharma Shaligram , Sharma Nivya , Wei Guanhao , Choudhary Ishita , Imhansi-Jacob Precious , Maganti Nagini , Pawar Shrikant , Rida Padmashree , Toss Michael S. , Aleskandarany Mohammed , Janssen Emiel A. , Søiland Håvard , Gupta Meenakshi. V. , Reid Michelle D. , Rakha Emad A. , Aneja Ritu
Published: December 2021

Centrosome amplification (CA) has been implicated in the progression of various cancer types. Although studies have shown that overexpression of PLK4 promotes CA, the effect of tumor microenvironment on polo-like kinase 4 (PLK4) regulation is understudied. The aim of this study was to examine the role of hypoxia in promoting CA via PLK4. We found that hypoxia induced CA via hypoxia-inducible factor-1α (HIF1α). We quantified the prevalence of CA in tumor cell lines and tissue sections from breast cancer, pancreatic ductal adenocarcinoma (PDAC), colorectal cancer, and prostate cancer and found that CA was prevalent in cells with increased HIF1α levels under normoxic conditions. HIF1α levels were correlated with the extent of CA and PLK4 expression in clinical samples. We analyzed the correlation between PLK4 and HIF1A mRNA levels in The Cancer Genome Atlas (TCGA) datasets to evaluate the role of PLK4 and HIF1α in breast cancer and PDAC prognosis. High HIF1A and PLK4 levels in patients with breast cancer and PDAC were associated with poor overall survival. We confirmed PLK4 as a transcriptional target of HIF1α and demonstrated that in PLK4 knockdown cells, hypoxia-mimicking agents did not affect CA and expression of CA-associated proteins, underscoring the necessity of PLK4 in HIF1α-related CA. To further dissect the HIF1α-PLK4 interplay, we used HIF1α-deficient cells overexpressing PLK4 and showed a significant increase in CA compared with HIF1α-deficient cells harboring wild-type PLK4. These findings suggest that HIF1α induces CA by directly upregulating PLK4 and could help us risk-stratify patients and design new therapies for CA-rich cancers.

Implications:

Hypoxia drives CA in cancer cells by regulating expression of PLK4, uncovering a novel HIF1α/PLK4 axis.
Early Tumor–Immune Microenvironmental Remodeling and Response to First-Line Fluoropyrimidine and Platinum Chemotherapy in Advanced Gastric Cancer
Authors: Kim Ryul , An Minae , Lee Hyuk , Mehta Arnav , Heo You Jeong , Kim Kyoung-Mee , Lee Song-Yi , Moon Jeonghyeon , Kim Seung Tae , Min Byung-Hoon , Kim Tae Jun , Rha Sun Young , Kang Won Ki , Park Woong-Yang , Klempner Samuel J. , Lee Jeeyun
Published: December 2021

Chemotherapy is ubiquitous in first-line treatment of advanced gastric cancer, yet responses are heterogeneous, and little is known about mediators of chemotherapy response. To move forward, an understanding of the effects of standard chemotherapy on the tumor–immune microenvironment (TME) is needed. Coupling whole-exome sequencing, bulk RNA and single-cell transcriptomics from paired pretreatment and on-treatment samples in treatment-naïve patients with HER2-positive and HER2-negative gastric cancer, we define features associated with response to platinum-based chemotherapy. Response was associated with on-treatment TME remodeling including natural killer (NK) cell recruitment, decreased tumor-associated macrophages, M1-macrophage repolarization, and increased effector T-cell infiltration. Among chemotherapy nonresponders, we observed low/absent PD-L1 expression or modulation, on-treatment increases in Wnt signaling, B-cell infiltration, and LAG3-expressing T cells coupled to an exodus of dendritic cells. We did not observe significant genomic changes in early on-treatment sampling. We provide a map of on-treatment TME modulation with standard chemotherapy and nominate candidate future approaches.

Significance:

Using paired pretreatment and on-treatment samples during standard first-line chemotherapy, we identify chemotherapy-induced NK-cell infiltration, macrophage repolarization, and increased antigen presentation among responders. Increased LAG3 expression and decreased dendritic cell abundance were seen in nonresponders, emphasizing remodeling of the TME during chemotherapy response and resistance.

This article is highlighted in the In This Issue feature, p. 873
Mask-Based versus Frame-Based Gamma Knife ICON Radiosurgery in Brain Metastases: A Prospective Randomized Trial
Authors: Régis Jean , Merly Louise , Balossier Anne , Baumstarck Karine , Hamdi Hussein , Mariani Sarah , Delsanti Christine , Vincent Marion , Nigoul Jean Marc , Beltaifa Yassin , Muracciole Xavier
Published: December 2021

Background: Radiosurgery is performed with a diversity of instruments relying usually either on a stereotactic frame or a mask for patient head fixation. Comfort and safety efficacy of the 2 systems have never been rigorously evaluated and compared. Material and Method: Between February 2016 and January 2017, 58 patients presenting with nonsmall cell lung cancer brain metastases have been treated by Gamma Knife radiosurgery (GKS) with random use of a frame or a mask for fixation were included patients older than 18, with <5 brain metastases (at the exclusion of brainstem and optic pathway’s locations) and no earlier history of radiotherapy. The primary outcome measure was the pain scale assessment (PSA) at the beginning of the GKS procedure. Results: The PSA at the beginning of the GKS procedure was not different between the 2 groups. The PSA at the day before GKS, before magnetic resonance imaging, just after frame application, and the day after radiosurgery (departure) has shown no difference between the 2 groups. At the end of the radiosurgery itself (just after frame or mask removal) and 1 h after, the mean pain scale was higher in patients treated with the frame (p < 0.05 and p < 0.001, respectively) but 2 patients were not able to tolerate the mask discomfort and had to be treated with frame. Tumor control and morbidity probability were demonstrated to be no difference between the 2 groups in this population of patients with BM not in highly functional area. The median of the extra dose to the body due to the cone-beam computed tomography was 7.5 mGy with a maximum of 35 mGy in patients treated with a mask fixation (null in the others treated with frame). Mask fixation was associated to longer treatment time although the beam on time was not different between the 2 groups. Conclusion: In selected patients, with brain oligo-metastases out of critical location, single-dose mask-based GKS can be done with a comfort and a safety efficacy comparable to frame-based GKS. There seems to be no clear patient data that confirm the value of the mask system with regards to comfort.
Verumontanum Polyp in an Adult Man: Diagnosis by Ultrasonography
Authors: Kutlutürk Şahin Neşe , Deveci Serkan
Published: December 2021

The fibroepithelial polyp of the urethra is rare in adults. Hematuria and obstructive urinary symptoms are the most common findings. The investigation of these polyps usually includes imaging exams (voiding cystourethrography and ultrasonography) and urinary endoscopy. However, the diagnosis is primarily established by pathology. Ultrasonography can aid in diagnosis, as it can identify a polypoid lesion that can extend to the bladder neck, and cystourethroscopy allows the direct visualization of the lesion. We report this case of a polyp of the prostatic urethra in an adult male using prospective real-time sonographic diagnosis.
Does Whole-Body Vibration Training Have a Concurrent Effect on Bone and Muscle Health? A Systematic Review and Meta-Analysis
Authors: Harijanto Christel , Lim Anthony , Vogrin Sara , Duque Gustavo
Published: December 2021

Background: Aging results in musculoskeletal disorders, which are a leading cause of disability worldwide. While conventional nonpharmacological treatments have included interventions such as resistance exercise, there are subgroups of people who may be at risk of exercise-related injuries, for example, falls. Whole-body vibration (WBV) is an intervention that helps improve musculoskeletal function and is viable for those with limited mobility. Objectives: Whether WBV has a dual effect on bone and muscle conditions remains unknown. We aim to assess the evidence of the effects of WBV on bone and muscle parameters concurrently in older people. Methods: Under Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines, a systematic literature search was performed in MEDLINE, EMBASE, EMCARE, and the Cochrane Central Registry of Controlled Trials. The main outcomes were changes in bone and muscle parameters. Results: Our meta-analysis showed that WBV does not have significant synergistic effects on measured bone (bone mineral density [BMD] in the hip and lumbar spine) and muscle (lean muscle mass and sit-to-stand time) outcomes, compared to controls (i.e., no WBV included). Conclusion: While there were no significant results, the included studies are limited by small sample size and variable intervention protocols and follow-up periods. Further trials should endeavor to measure both bone and muscle outcomes concurrently with a longer follow-up time. Osteoporosis status in participants must also be considered as it is not yet possible to exclude that WBV may have a significant effect on BMD in people with known osteoporosis. WBV does not appear to simultaneously influence bone and muscle health in older people, and future research is required to establish a regimen that may lead to measurable clinical efficacy.
Efficacy Assessment of the High-Frequency High-Intensity Focused Ultrasound as a New Treatment for Actinic Keratosis
Authors: Seyed Jafari S. Morteza , Cazzaniga Simone , Bossart Simon , Feldmeyer Laurence , Pelloni Lorenzo , van Rhyn Maja , Angermeier Sarina , Adatto Maurice , Hunger Robert E. , Heidemeyer Kristine
Published: December 2021

Background: Actinic keratosis (AK) is the most common precancerous cutaneous lesion, with risk of progression to cutaneous squamous cell carcinoma. In the current study, we evaluated the efficacy of 20-MHz high-intensity focused ultrasound (HIFU), as a new treatment modality for AK. Materials and Methods: Patients with AK lesions (grades I–III) treated with HIFU were included in the study. The clinical assessment was performed 3 months after therapy. Results: Twenty-one patients (14 men, 7 women) with 108 AK lesions (grades I–III) were included in the current study. Ages ranged from 62 to 85 years (mean 72.6 years). Clinically complete resolution of the actinic damage in the treated area was detected in 72.2% of lesions. Furthermore, 28 lesions (26%) showed a reduction of the AK grade, or partial response, after the therapy. Most of the patients experienced annoying but short pain during the procedure. However, late adverse effects of the therapy, such as hypopigmentation, hyperpigmentation and erythema were reported only in a small portion of the lesions. Conclusions: 20-MHz HIFU could be an effective and safe alternative treatment for AK.