bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on European Container Ports Based on Lotka-Volterra Model
Authors: Xu Yiwen
Published: June 2021

Europe is one of the important regions with the global container shipping business. Studying competition among port container business helps to improve the overall containerized transportation efficiency in Europe and assist liners to make correct decisions under the new global shipping pattern. Therefore, this paper uses non-autonomous Lotka-Volterra model to quantitatively study the type and degree of competition among major European container ports. The result shows that the ports in the Mediterranean region tend to be predatory and competitive. Besides, this paper also predicts the future trend of competition and cooperation of European container ports under the scenarios of “Sulphur Restriction Order” by modifying the utility function.
Layout analysis and optimization design for Zhengding Bus Terminal
Authors: Li Yanwei
Published: June 2021

As an important component of road transportation, the bus terminal has always been the focus of research. Therefore, this article uses a combination of quantitative and qualitative analysis to study Zhengding third-level bus terminal from the perspective of layout analysis. On the basis of actual investigation, the relevant indicators of the bus terminal scale are calculated. At the same time, the analysis of the three functional areas and process flow lines inside the passenger station revealed that the passenger station has the problems of intersection of pedestrians and vehicles and the unreasonable and imperfect layout of the ticket waiting hall. Finally, a specific optimization plan is proposed and optimized for the problems existing in Zhengding bus terminal.
Summary of Research on Supporting Facilities and Structure Vibration and Noise Reduction of High-Rise Buildings
Authors: Jinfeng Rui , Lin Wang , Pei Lu
Published: June 2021

At this stage, mid-to-high-rise buildings are flooding every corner of my country’s urban construction, and large-scale buildings have also become an inevitable result of urban planning and development. The comfort and safety issues associated with mid-to-high-rise buildings as well as the comfort and safety caused by structural vibration have also come into our sight. This article will explain the research on the vibration control of building power systems, air conditioning systems, network systems, pipeline systems and other building supporting facilities, as well as the research on the vibration control of building structures. These details reflect the improvement of vibration and noise reduction research in the comfort and safety of middle and high-rise buildings.
Evaluation and application of shallow buried tunnel construction safety based on combined empowerment-multidimensional cloud model
Authors: Liu Shang , Song Jie , Xu Run , Zhang Changyong , Zhong Guoqiang , Wang Chao
Published: June 2021

In order to study the influence of various factors on the construction safety of shallow buried tunnels, a multifactor evaluation model consisting of 9 indicators, such as tunnel size, the buried depth, surrounding rock condition and construction management, is established from the perspective of “4M1E” by combining the characteristics of shallow buried tunnel construction by borehole-blasting method. It combines the advantages of subjective weighting method AHP and objective weighting method CRITIC, and determines the comprehensive weight values through the combined weighting method, which is used to improve the weight assignment of multi-dimensional normal cloud model, and evaluates the stability of the surrounding rock at the entrance and exit of the shallow buried tunnel based on the concepts of expectation, entropy and super entropy of the cloud model. And then it accurately obtains the construction safety of the entrance and exit of the shallow buried tunnel, and the evaluation results have scientific guidance for the control of construction risks.
Experimental study on anti-freezing and thawing of preparation of wet mixed mortar with full component recycled sand in plastering engineering
Authors: Yang Yuhao , Jin Shengji , Cao Fubo
Published: June 2021

In this study, in order to study the freeze-thaw resistance of wet-mix plaster mortar after replacing artificial sand (AS) with full-component recycled sand (FCRS) and recycled brick powder (RBP) instead of fly ash (FA), ratio of binding material to fine aggregate (RBMFA) (1:5, 1:6 and 1:7), types of fine aggregate (TFA) (AS and FCRS) and kinds of mineral admixture (KMA) (FA and RBP) were considered as research variables. RBMFA, TFA and KMA have an effect on freeze-thaw resistance performance of wet mixed mortar (WMM) could be studied with the slow freezing method. Moreover, new way of application of brick powder was explored. Take advantage of full-component recycled fine aggregate instead of traditional AS to prepare wet mix plaster mortar (WMPM) have three meanings of saving natural resources, protecting the environment and achieving superior economic benefits. Numerical studies indicated that RBMFA is one of the most main influence factors of the freezing and thawing resistance of mortar. Under 25 freeze-thaw cycles, mass loss rate (MLR) and strength loss rate (SLR) of mortar increase with the reduction of rubber sand ratio, the average MLR of RBMFA 1:7 to 1:5 increased by 2.5%, and the average SLR increased by 7.4%. Replacing AS with FCRS and replacing BP with FA can not only alleviate the shortage of natural sand and FA, but also it could realize the resource utilization of building waste.
CFD-based fluid calculation model selection and field analysis for small reactors
Authors: Cheng Lei , Zhao Xinyu , Li Miao , Fang Xiaoqing
Published: June 2021

To improve the accuracy of reactor design, this article uses k-ε, DES, LES, and SST four methods to compare the simulation results of the velocity field in the blade area, turbulence intensity, and velocity distribution of the fluid in the reactor, and predict the appropriate field model of the reactor calculation. Therefore, the calculation process is more suitable for the SST model of small reactors.
Predicting the Unconfined Compressive Strength of Rubber Fiber Modified Cemented Paste Backfill Using Support Vector Machine
Authors: Yu Zhuoqun , Wang Yongyan , Huang Sa , Zhou Tongtong , Chang Le
Published: June 2021

Machine learning based on the support vector machine algorithm was used for the prediction of the unconfined compressive strength of rubber fiber modified cemented paste backfill. Grid analysis was used to find the optimal hyper-parameters. The SVM model was well trained on the training set, and performed well on the testing set. Analysis results showed that the SVM model achieved a higher accuracy. The squared correlation coefficient values were 0.9914 and 0.9321 on the training set and testing set, respectively. It is recommended that laboratories around the world could share UCS tests results of CPB to expand the dataset for the training of prediction models.
The application of 3D design technology in the design of 220kV substation in Miluo Western
Authors: Wen Jiang , Chaoqi Xiong , Wei Zhai , Xinxin Xiang , Hongtao Ju
Published: June 2021

Based on engineering information and geographic information data, through the integrated application of 3D modeling technology and digital collaborative design technology, the 3D visual design and information integration of power transmission and transformation projects are completed, 3D design can realize complex underground pipeline layout, cable optimization layout, collision inspection, visual display, etc. It is helpful to reduce the soft and hard collision of the project, ensure the design safety and quality, optimize the work quantity and guide the construction. In this paper, through the application of 3D design technology in the design of 220kV substation in Miluo Western, the main aspects and benefits of application are summarized, and the existing problems are analyzed for reference in other engineering applications.
Lubrication characteristics study of main bearings on crankshaft balance rate
Authors: Li Yunqiang , Zhu Guixiang , Liu Xin , Sun Nannan , Meng Qingbin , Yang Zhihao , Zhao Junsheng
Published: June 2021

Unbalanced inertia force and moment of crankshaft generated by cylinder pressure have a significant effect on the vibration characteristics of diesel engine, but the study on the lubrication characteristics of crankshaft by balance rate needs to be studied. Based on Greenwood-Tripp asperity contact theory and average Reynolds equation, an elastohydrodynamic (EHD) lubrication model of the main bearing for a V-12 diesel engine is developed, and the influence of different balance rates on lubrication characteristics is analyzed. On this basis, a factorial experiment of ten influencing factors including the balance rate is designed, and the factors that significantly affected the lubrication characteristics of the main bearing are screened out by factor effect diagram, statistical analysis and residual probability diagram. The results show that the crankshaft with different balance rate has a great influence on the lubrication performance. With the increase of balance rate, the minimum oil film thickness first increases and then decreases, and the maximum oil film pressure first decreases and then increases. The balance rate, bearing width, bearing clearance, bush repair and oil viscosity have significant effects on the performance of main bearing, among which the balance rate of crankshaft has the greatest effect on the minimum oil film thickness, the maximum rough contact pressure and the average friction power loss.
The design of the traffic plan of line S1 of Taizhou railway in Zhejiang Province
Authors: Li Zimu
Published: June 2021

At present, China is in the period of rapid urbanization construction, and gradually build a set of efficient, new and fast comprehensive urban transportation system. The urban railway construction with the same city commuter and convenient public transport service can effectively extend the urban development space and accelerate the adjustment process of urban planning and layout. According to the current situation of Taizhou’s economic and traffic development, as well as Taizhou’s unique geographical advantages, combined with the relevant research at home and abroad, this paper comprehensively discusses the necessity of building Taizhou City railway line S1. By sorting out the relevant preliminary, short-term and long-term passenger flow forecast data, this paper calculates the maximum section passenger flow in each period of the day, analyzes the characteristics of passenger flow in each period, compiles the full-time driving plan compilation data, and makes corresponding adjustments according to the actual situation, and finally designs the full-time driving plan to meet the passenger flow demand in each period. The second chapter describes the research background, the third chapter analyzes the characteristics of passenger flow, and the fourth chapter designs the driving plan and draws the train diagram.
Structural Optimization of Subway Aluminum Alloy Car Body Analyzed by Optistruct Software
Authors: Wang Ning , An Ziliang , Bai Dingsong , Liu Shaofeng , Yu Xintong
Published: June 2021

In accordance with the life cycle cost of the vehicle, the structure of the aluminum alloy car body structure of Shanghai Line 16 was optimized based on the Optistruct software. Then the load combination conditions are divided into 9 operating conditions based on EN12663-2010. Furthermore, the optimized car body is judged whether it is qualified. The experimental results show that the optimized car body structure of Shanghai Line 16 can meet EN12663 and TB/T1335. In this paper, it provides a high application prospect for reducing LCC of the aluminum alloy car body in the design stage.
Discussion and analysis on problems of lube oil cooler and the oil cooler three way valve of a thermal power unit
Authors: Junfeng-Qi  , Yuzhu-Zhao  , Ke-Li  , Zhengfeng-Wu  , Jinliang-Liu
Published: June 2021

Lube oil cooler is an important heat exchange equipment to provide suitable oil temperature for steam turbine unit. Its reliability is directly related to the normal operation of the unit. Combined with the system commissioning work, this paper finds out the problems existing in the lube oil cooler body and the oil cooler three way valve, and puts forward several improvement and optimization schemes, so as to improve the operation status of the equipment, improve the reliability of the system, and also facilitate the maintenance of the equipment, which provides a design reference for ensuring the safe and economic operation of the unit.
DCS Modification Design for I&C System of Nuclear Power Plants
Authors: Nanchuan Liu , Fan Lu , Libing Zhang , Yanjun Hu
Published: June 2021

Taking the DCS modification project of I&C system in the nuclear power plant as an example, this paper introduces a solution to replace the traditional I&C system with DCS (or digitization technology) from the aspects of function optimization, power supply design, I/O channels design, HMI, cabinet layout, etc. The modified I&C system retains all the functions of the original system, and greatly improves the reliability, interactivity, scalability and convenience in maintenance of the system.
Research on live detection technology of Arrester Based on wireless synchronization technology
Authors: Zhong Dantian , Li Zhongyi , Wu Hongyu , Wu Di
Published: June 2021

There are a lot of MOA in power system, and it’s reliability is very important to power system. In order to ensure the safe operation of MOA, the running state of MOA must be tested regularly. This paper studies the traditional method of live detection of arrester used in substation. Based on the principle of live detection of wired arrester, a new method of measuring Arrester Based on wireless synchronization technology is designed. It provides a new measuring method for the live detection technology of lightning arrester in substation, and detects the aging and damp of arrester more efficiently and safely.
Determination Method of Contact Ablation Degree of Power System Circuit Breaker Based on Power Load Property
Authors: Wang Shao Ran , Zhao Xiao Bing , Wang Chao , Ping Man Xiao , Yu Bo , Xin Piao Yong , Yang Jie
Published: June 2021

In the field of electrical engineering, the stable operation of circuit breaker is one of the important indexes to ensure the safety and stability of power system. Because the influence of load property on electromagnetic wave waveform is not considered, the method to determine the ablation degree of circuit breaker by using the characteristics of radiated electromagnetic wave is not completely accurate. Therefore, this paper proposes a method to determine the ablation degree of circuit breaker considering the load properties. By adding load factor, the ablation degree of circuit breaker contact can be determined more accurately. When the load is resistive load, the load factor is 1, when the load is inductive load, the load factor is 2.5, when the load is capacitive load, the load factor is 3. When the duration of the radiated electromagnetic wave exceeds the corresponding time, it can be judged that the contact is seriously ablated. The method proposed in this paper mainly uses electrical detection means to realize the rapid determination of the ablation degree of the circuit breaker contact and avoid the misjudgment caused by not considering the nature of the load.
Structural response analysis of wind turbine under different wind speeds
Authors: Huo Qian
Published: June 2021

Taking a 2 MW horizontal axis wind turbine in a wind farm in Northwest China as the research object, the structural response analysis of wind turbine considering fluid structure coupling effect under different inflow was carried out by using ANSYS Workbench software. The results show that when the incoming wind speed is cut-in wind speed, the displacement and stress change slightly; when the incoming wind speed is between the cut-in and cut-out wind speed, the structural response law of the wind turbine is the same. The maximum of displacement and stress increase with the increase of wind speed, and the maximum displacement of the blade is located in the tip, and the maximum stress of the blade is concentrated in the middle of the blade; The maximum displacement of the tower is located at the top, and the maximum stress of the tower is concentrated at the bottom. The results have important reference value for the design and safe operation of wind turbine.
Dielectric and Design and Experimental Study of GIS Gas Chamber HF and Micro Water Dual Fiber Laser Detection System
Authors: Shiling Zhang , Xiaozhe Zeng
Published: June 2021

HF gas and trace moisture content, as the primary characteristic by-products of SF6 gas decomposition reaction, are of great significance to the fault diagnosis of high voltage SF6 gas insulated high voltage power equipment. In this paper, the typical discharge fault types in GIS are analyzed, and the decomposition products corresponding to different discharge types are summarized. The physical and chemical mechanism of HF generation in the early dissociation process of SF6 and under certain micro water and micro oxygen conditions is explained, and the experimental platform is built to carry out the simulation generation experiment of HF gas and micro water. The results show that choosing the best target absorption line suitable for sensitive and selective gas sensing can eliminate interference, simplify the system and reduce the cost. Furthermore, under the experimental conditions, the self-developed TDLAS online detection technology is used to realize the effective detection of HF gas and trace water in GIS discharge room. The 1278nm and 1392nm laser sources are selected respectively, and the TDLAS technology based on dual fiber time-sharing multiplexing is feasible for HF and trace water measurement. The stability and reliability of the technology are verified, which can provide effective technical support for on-line detection of HF gas in GIS, and has good engineering application value.
A method of mining electricity consumption behaviour based on CC-DWT
Authors: Li Fan , Tian Yingjie , Wu Yi , Liu Yihan
Published: June 2021

In this paper, a fusion clustering algorithm based on discrete wavelet transform called CC-DDWT is proposed. In this method, the preliminary feature construction of load curve is realized by multi-layer discrete wavelet transform, and the approximate component and detail component are formed, and then the clustering fusion is carried out. The experimental results show that the typical load patterns of a single user extracted by this method are more reliable than the traditional methods.
Optimization of horizontal well pattern in low permeability layered reservoir
Authors: Xia Wang , Yayuan Tao , Xiuwei Wang , Jing LI , Qihao HU , Xiaoying Shi , Minmin Shao
Published: June 2021

The southern part of Jin45 fault block is a low permeability layered reservoir with thin oil layer thickness. And the development of horizontal well pattern has good economic benefit in Jin45 fault block. The oil layer distribution of reservoir is quite different. The distribution of main layer is stable, but the distribution of non-main layer is unstable. In this study, through reservoir engineering method and numerical simulation method, the horizontal well pattern direction, well pattern form, well spacing and horizontal well length are optimized to determine the horizontal well pattern of main layer. On this basis, according to the principle of “parallel deployment of horizontal wells and sharing injection-production well pattern”, the horizontal well pattern of non-main layer is preliminarily designed to ensure the development effect and economic benefit to the greatest extent.
Study on low frequency sound absorption characteristics of cavity coating with local resonance
Authors: Jiabei Wang , Hao Zhou
Published: June 2021

It is of great significance to study the low frequency acoustic absorption characteristics of acoustic cover for improving the acoustic stealth performance of submarine. Considering the sound absorption performance of cavity coating and local resonant thin film structure, a finite element model of cavity acoustic coating with local resonance is established. The sound absorption characteristics of the composite structure in the range of 10-1000Hz are studied. The influence law of the sound absorption performance was obtained by adjusting the geometric parameters of the composite structure. The results show that : (1) The coupling between the local resonant structure and the cavity coating can produce a sound absorption peak, and the sound absorption coefficient can be increased by 30% at most; (2) The first sound absorption peak produced by the composite structure is mainly related to the cavity overburden; (3) The second sound absorption peak is mainly generated by the coupling between the cavity coating and the local resonance structure. The results can provide a theoretical basis for the design and application of acoustic coating.
Underground Thermal Engermal Energy Storage Storage Concrete Piples Around the Simulation and Analysis of Temperature Fileds
Authors: Huijun Duan
Published: June 2021

Based on the establishment of the concrete pile test-bed, the selection of concrete materials and the selection of insulation materials outside the concrete pile are compared, and the better materials are obtained. The heat exchanger is embedded in the concrete pile in advance, and the heat is stored in the concrete pile by using the heat source. By measuring the temperature and other parameters in different depths of concrete pile, the thermal storage effect of thermal storage pile is analyzed and the optimal thermal storage model is established. In this paper, through the study of the relevant data about the underground heat storage model of soil heat pump, the physical model and mathematical model used for the simulation and analysis of the temperature field around the buried pipe heat exchanger of underground concrete heat storage pile are obtained. In this paper, the single U vertical buried pipe is selected as the physical model, and the cylindrical heat source model is selected as the mathematical model, so as to simplify the heat exchanger around the buried pipe of underground concrete. The model of heat transfer is established. The mathematical model is analyzed with MATLAB. In this paper, the changes of concrete temperature with depth, radius, flow rate, specific heat and thermal conductivity are analyzed. The influence trend of these factors on the concrete temperature field around the buried pipe of the heat storage pile is summarized.

Classification number: TK521 Document identification code: A
The influence of laser power and scanning speed on the dimensional accuracy of SLS formed parts
Authors: Hou Gaoyan , Yu Zhongzhen , Ye Dong
Published: June 2021

In SLS sintering forming, laser power and scanning speed are two important process parameters, which directly affect the dimensional accuracy of sintered parts. Using PA2200 powder as the forming material, the influence of laser power and scanning speed on the dimensional accuracy of the sintered part was analyzed. Through theoretical analysis and experimental verification, the best combination of parameters was obtained. The laser power is 40 W and the scan speed is 5000 mm/s. The dimensional accuracy of the sintered parts is obtained by X-direction deviation -0.35 %, Y-direction deviation -0.4 %, and Z-direction deviation -0.25 %.
Application and Development Trend of Grouting Technology in Prevention and Control of Ordovician Limestone Water Disaster in North China Type Coalfields
Authors: Xuedong Kan , Le Tian , Xuliang An , Shuitao Guo , Xue Yang , Peiguo Heng
Published: June 2021

The hydrogeological conditions of North China type coalfields are complex. With the large-scale development of deep resources, the probability of Ordovician limestone water inrush from coal seam floor increases. Ordovician limestone water disaster has become a serious safety threat to deep mining in North China type coalfields. Since the application of grouting technology can quickly block the water inrush passage and eliminate potential floods, it has obvious advantages in the prevention and control of Ordovician limestone water disasters in North China type coalfields. Equipment progresses, such as working face grouting, downhole directional drilling grouting and surface directional drilling grouting, promote the sustainable development of grouting technology for prevention and control of Ordovician limestone water disaster in North China type coalfields. This paper analyzed the development process of grouting technology in the prevention and control of Ordovician limestone water disaster in North China type coalfields, analyzed the problems encountered for surface directional drilling grouting in practice based on advanced Ordovician limestone water disaster treatment project cases, and pointed out the development direction of surface directional drilling grouting technology for regional water disaster prevention and control. This paper is of important reference significance for prevention and control of Ordovician limestone water disaster in deep mining floor of North China type coalfields.
Research on CMS decomposition of South Korea’s manufacturing exports to China
Authors: Kim J S
Published: June 2021

This paper analyzes the export performance of South Korea’s manufacturing products to China from 2000 to 2020 by using Constant Market Share (CMS) model. The manufacturing products are mainly electrical machinery, equipment, vehicles, optical photographic, iron and steel, organic chemicals, and related products. According to the analysis, South Korea’s manufacturing products to China had continued to increase in demand of the China market from 2000 to 2014, but it has stagnated or declined since 2015, owing to the development of manufacture-related technology of China and its lower dependence on South Korea’s products. Through CMS decomposition, it is found that: the structure effects in stages of 2000-2015, 2006-2010 and 2011-2015 contributed the most to the change of exports in China market. However, during the period of 2016-2020, it was a high negative level due to the increased self-sustaining power of China. Moreover, the structure effects are mainly from the growth effects, except for the period of 2016-2020, which was from the commodity effect. In all the four stages, the competitive effect has a positive value. Especially, in the period of 2016-2020, it reached a highest level of 620.20%, because of its high technology and high quality. Through second order decomposition, it is found that the competitive effects are mainly from the overall competitive effects, except for the period of 2006-2010, which is mainly from commodity competitive effect. In the case of residual effect, compared with the structure effect and the competitive effect, its contribution to the change of exports is very low. And the residual effects are mainly from the pure residual effects rather than dynamic effects.
Application of AnMBR Ion Exchange Technology in Water Treatment
Authors: Zhao Zhenchao , Wang Xiaodong
Published: June 2021

Ion exchange technology is widely used. Ion exchange technology is often used in industrial separation and purification. Ion exchange technology has the advantages of deep purification, high efficiency and comprehensive recovery. With the continuous development of ion exchange technology, the application of ion exchange technology in water treatment is increasing. This article details the application of ion exchange technology in water treatment.
Effects of organic phosphonic acid on the germination characteristics of plants after remediation of Cd contaminated soil
Authors: Changjia Jiang , Shuang Cui , Baodan Yang , Xiuli Sun , Qi Feng
Published: June 2021

The heavy metal Cd seriously affects the growth and development of humans, animals and plants, at the same time, it has the characteristics of wide sources and easy delivery. In this paper, the effects of Cd contaminated soil remediation by biodegradable organic phosphonic acids HEDP, BHMTPMPA, HDTMPA and ATMP on the germination characteristics of plants were studied. The results showed that when the concentration of organic phosphonic acid HDTMPA was 4%, the germination characteristics of Zinnia elegans Jacq. are the best among the four organic phosphonic acids, the germination rate, germination potential, germination index, vigor index, root length, bud length and seedling dry weight were 62%, 25.1, 11.8, 41.3, 1.8 cm, 3.5 cm and 158 mg respectively.
Study on Seismic Precursory Anomaly Signals Based on Critical Slowing Phenomena
Authors: Su Xiaoyun , Chen Lijun , Wang Wencai , Liu Hongmei , Zhou Weidong
Published: June 2021

This paper applied the principle of critical slowing down to the processing of radon concentartions observation data, calculated the autocorrelation coefficient and variance which can characterize critical slowing down by taking Wenchuan Ms8.0 earthquake on May 12, 2008, Lushan Ms7.0 earthquake on April 20, 2013, Minxian-Zhangxian Ms6.6 earthquake on July 22, 2013, Jiuzhaigou Ms7.0 earthquake on August 8, 2017 as examples. The result indicated that the water radon concentration at several stations has obvious critical slowing phenomenon before server earthquakes. The formation mechanism of radon concentration anomalies in seismic underground fluids was discussed in the context of the focal mechanism solution of several earthquakes. It is considered that the phenomenon of critical slowing down before server earthquakes is related to the earthquakes occurrenced combined with the hydrodynamic mechanism of radon anomaly and the structure of the abnormal points.
Exploring Proximal LGBTQ+ Minority Stressors Within Physical Activity Contexts from a Self-determination Theory Perspective
Authors: Herrick Shannon S C , Rocchi Meredith A , Sweet Shane N , Duncan Lindsay R
Published: June 2021

Background

LGBTQ+ (lesbian, gay, bisexual, transgender, queer, etc.) individuals experience challenges such as discrimination and marginalization (referred to as minority stressors) that are detrimental to their mental and physical health. Specifically, proximal or internalized LGBTQ+ minority stressors may influence motivation for and willingness to participate in physical activity.

Purpose

To explore whether proximal LGBTQ+ minority stressors relate to the basic psychological needs—motivation—physical activity pathway, as per self-determination theory.

Methods

An online cross-sectional survey was completed by 778 self-identified LGBTQ+ adults. Structural equation modelling analyses were used to examine how proximal LGBTQ+ minority stressors relate to the motivational sequence.

Results

Findings support that proximal LGBTQ+ minority stressors are negatively associated with psychological need satisfaction within physical activity (β = −.36), which in turn is positively associated with autonomous motivation (β = .53) and reported physical activity participation (β = .32). Overall, the final model accounted for 13% of variance in need satisfaction (small effect size), 53% of variance in autonomous motivation (moderate-large effect size), and 10% of variance in moderate-to-vigorous physical activity levels (small effect size).

Conclusions

Future research focused on increasing LGBTQ+ participation in physical activity should investigate the effects of (a) reducing proximal LGBTQ+ minority stressors and (b) better supporting LGBTQ+ adults’ autonomy, competence, and relatedness within physical activity contexts.
Risk Assessment of Human Papillomavirus–Positive Cytology-Negative Cervical Cancer Screening in Black and White Women
Authors: Miller Daniel L , Graham Ashleigh , Davis Katelynn E , Kaur Harsimar , White Marissa , Maleki Zahra , Rodriguez Erika F
Published: June 2021

Objectives

As we move toward human papillomavirus (HPV) only as the preferred cervical cancer screening method, we performed a retrospective analysis of Black and White women with negative cytology (Papanicolaou negative [PAPneg]) and positive high-risk HPV (hrHPV) (HPVpos) results and determined follow-up.

Methods

We searched our pathology data system for patients with PAPneg/HPVpos results (2017-2019). Follow-up data were reviewed (39 months), and a comparison among race was performed.

Results

In total, 1,728 patients were identified (Black, 53%; White, 47%). Twenty-nine percent of the patients had no follow-up with no difference among the races. HPV 16 was more common among Whites (P < .01), while non-16/18 hrHPV was more common among Black patients (P = .01). A total of 30 (3.3%) Black and 26 (3.2%) White patients were diagnosed with cervical intraepithelial neoplasia grade 2/3 (CIN 2/3). More White women were diagnosed on biopsy alone (negative endocervical curettage) compared with Black women (20 vs 9, P < .01). Meanwhile, there were 21 Black and 6 White women with CIN 2/3 on endocervical curettage (P = .01).

Conclusions

Follow-up of women with PAPneg/HPVpos remains a challenge. There was no disparity in follow-up when cohorts were compared. However, Black women had higher numbers of high-grade intraepithelial lesions on endocervical curettage.
Outcomes of peroral endoscopic myotomy in patients with achalasia and prior bariatric surgery: A multicenter experience
Authors: Bomman S , Klair J S , Ashat M , El Abiad R , Gerke H , Keech J , Parekh K , Nau P , Hanada Y , Wong Kee Song L M , Kozarek R , Irani S , Low D , Ross A , Krishnamoorthi R
Published: June 2021

Peroral endoscopic myotomy (POEM) in patients with achalasia who are status post bariatric surgery may be technically challenging due to postsurgical scarring and altered anatomy. The aim of the study was to assess the efficacy and safety of POEM for achalasia in patients with prior bariatric surgery. A review of prospectively maintained databases at three tertiary referral centers from January 2015 to January 2021 was performed. The primary outcome of interest was clinical success, defined as a post-treatment Eckardt score ≤ 3 or improvement in Eckardt score by ≥ 1 when the baseline score was <3, and improvement of symptoms. Secondary outcomes were adverse event rates and symptom recurrence. Sixteen patients status post Roux-en-Y gastric bypass (n = 14) and sleeve gastrectomy (n = 2) met inclusion criteria. Indications for POEM were achalasia type I (n = 2), type II (n = 9), and type III (n = 5). POEM was performed either by anterior or posterior approach. The pre-POEM mean integrated relaxation pressure was 26.2 ± 7.6 mm Hg. The mean total myotomy length was 10.2 ± 2.7 cm. The mean length of hospitalization was 1.4 ± 0.7 days. Pre- and postprocedure Eckardt scores were 6.1 ± 2.1 and 1.7 ± 1.8, respectively. The overall clinical success rate was 93.8% (15/16) with mean follow-up duration of 15.5 months. One patient had esophageal leak on postprocedure esophagram and managed endoscopically. Dysphagia recurred in two patients, which was successfully managed with pneumatic dilation with or without botulinum toxin injection. POEM appears to be safe and effective in the management of patients with achalasia who have undergone prior bariatric surgery.
The Utility of a Bumble Bee (Bombus spp.[Hymenoptera: Apidae]) Brood Test for Evaluating the Effects of Pesticides
Authors: Krueger Annie J , Early Tara M , Ripperger Randy J , Cabrera Ana R , Schmehl Daniel R
Published: June 2021

Risk assessment for chemicals in the United States relies upon the honey bee (Apis meliffera L. [Hymenoptera: Apidae]) as a surrogate for other bee species. There is uncertainty in extrapolating honey bee toxicity data to bumble bees due to differences in life history strategies, food consumption, and nest structure. Here we evaluated the design of a queenless bumble bee microcolony test that could be considered for generating larval toxicity data. Three microcolony studies were conducted with Bombus impatiens to evaluate the effects of exposure to 1) diflubenzuron in pollen, 2) dimethoate in pollen, and 3) dimethoate in sucrose. Immature drone bee emergence, worker survival, pollen, and sucrose utilization were measured throughout the study duration. For dimethoate, a 10-d chronic adult bumble bee study was also conducted to compare microcolony endpoints to toxicity endpoints on individual adults. Microcolonies exposed to 10 mg diflubenzuron/kg pollen produced fewer adult drones despite no effects on worker survival. Microcolonies treated with dimethoate at ≥3 mg a.i./kg pollen and ≥0.1 mg a.i./kg sucrose solution produced fewer drones. Exposure to dimethoate in the 10-d chronic adult study resulted in direct mortality to the adult workers at ≥0.1 mg a.i./kg diet. Results from the 10-d study suggest direct effects of dimethoate on workers in the microcolony will alter provisioning of diet to the brood, resulting in lower drone production in the microcolony. Our data suggest that the microcolony study is only appropriate to assess brood effects to bumble bees for substances with low toxicity to adults, as demonstrated with diflubenzuron.
Two centres experience of lung cancer resection in patients with advanced non-small cell lung cancer upon treatment with immune checkpoint inhibitors: safety and clinical outcomes
Authors: Beattie Rory , Furrer Katarzyna , Dolan Daniel P , Curioni-Fontecedro Alessandra , Lee Daniel N , Frauenfelder Thomas , Hoeller Sylvia , Weder Walter , Bueno Raphael , Opitz Isabelle , Swanson Scott
Published: June 2021

OBJECTIVES

Recent trials have begun to explore immune checkpoint inhibitors for non-small cell lung cancer in the neoadjuvant setting, but data on tumour response and surgical outcome remain limited.

METHODS

Retrospective evaluation of clinical data from patients with non-small cell lung cancer treated with immune checkpoint inhibitors followed by lung resection was performed at 2 large volume institutions (1 North American, 1 European). Data were analysed using Chi-squared, Fisher’s and Wilcoxon rank-sum tests where appropriate.

RESULTS

Thirty-seven patients were identified from 2017 to 2019. Forty-nine per cent were Stage IIIB and IV. Forty-six per cent received immunotherapy alone and 54% in combination with chemo- and/or radiotherapy. Sixteen per cent of cases were successfully performed minimally invasively. Twenty patients were operated with lobectomy (6 of these with wedges or segments of a neighbouring lobe, 2 with sleeve resections and 1 with a chest wall resection), 4 with bilobectomies, 11 with pneumonectomy (including 5 extrapleural pneumonectomies and 1 atrial resection) and 1 with a wedge resection. Overall, 10 patients (27%) developed postoperative complications and the 90-day mortality was zero. One-year recurrence-free survival was 73% for stage II/IIIA and 55% for stage IIIB/stage IV. The major pathologic response rate was 34%.

CONCLUSION

In this retrospective study, lung resection after immunotherapy (alone or in combination) is safe, although often requires complex surgery. Due to increasing number of clinical trials adopting immunotherapy in the neoadjuvant setting, it is likely that this therapy will become part of standard of care. Immunotherapy may also allow surgery to have a role for selected patients with advanced disease.
Lipschitz Algebras and Lipschitz-Free Spaces Over Unbounded Metric Spaces
Authors: Albiac Fernando , Ansorena José L , Cúth Marek , Doucha Michal
Published: June 2021

We investigate a way to turn an arbitrary (usually, unbounded) metric space ${{\mathcal{M}}}$ into a bounded metric space ${{\mathcal{B}}}$ in such a way that the corresponding Lipschitz-free spaces ${{\mathcal{F}}}({{\mathcal{M}}})$ and ${{\mathcal{F}}}({{\mathcal{B}}})$ are isomorphic. The construction we provide is functorial in a weak sense and has the advantage of being explicit. Apart from its intrinsic theoretical interest, it has many applications in that it allows to transfer many arguments valid for Lipschitz-free spaces over bounded spaces to Lipschitz-free spaces over unbounded spaces. Furthermore, we show that with a slightly modified pointwise multiplication, the space ${\textrm{Lip}}_0({{\mathcal{M}}})$ of scalar-valued Lipschitz functions vanishing at zero over any (unbounded) pointed metric space is a Banach algebra with its canonical Lipschitz norm.
Application of powerline noise cancellation method in correlation identification of controlled source electromagnetic method
Authors: Yang Zhi , Tang Jingtian , Xiao Xiao , Jiang Qiyun , Huang Xiangyu , Hu Shuanggui
Published: June 2021

Powerline interference in the controlled source electromagnetic method has traditionally been one of the biggest conundrums plaguing geophysicists, and its conventional denoising methods primarily include filtering and noise estimation. The filter method leaches noise at specific frequency points, which might also filter useful signals; the noise estimation method significantly eliminates interference, whereas the premise is that the noise is stable after a short time and a recorder is necessary in the field. In the present study, using the periodicity and symmetry of powerline noise, we propose a subtraction and an addition method for cancellation of the powerline noise. First, the transmitted signal is optimized so that the equivalent transmitted signal is an m sequence; then the response signal is processed by using the cancellation method; subsequently, the correlation identification is applied and finally, we solve the earth impulse response by means of the Wiener filter deconvolution method. Simulation experiments and field data tests demonstrate that the powerline noise can be well suppressed by the cancellation method proposed in the present study, so that the system identification accuracy is greatly improved. The method is simple in principle and effective in removing powerline noise, which presents a novel perspective on noise elimination for system identification.
Acute traumatic abdominal wall hernia—value of the physical examination: case report
Authors: Hernandez Cervantes Barbara Yordanis , Martínez Lopez Duniesky , Guzman Lambert Radisnay , Rodríguez Gonzalez Mariuska , Meah Mary
Published: June 2021

Acute traumatic abdominal wall hernia (TAWH) is a rare type of hernia that occurs after a low or high velocity impact of the abdominal wall against a blunt object with few cases reported. Perforations of the hollow viscera commonly follow abdominal trauma and likely require surgery for hemorrhage and sepsis source control. We report a case where a high velocity impact of the abdominal wall against the stump of a felled tree caused a TAWH with concomitant gastric perforation in a 20-year-old male patient who required exploratory laparotomy with primary repair of the stomach and fascia. The physical examination findings without previous history of abdominal hernia and pneumoperitoneum in the chest X-ray made suspect our diagnosis and it was confirmed intraoperatively. At 3 months postoperatively the patient has a strong abdominal wall. It is imperative to emphasize the importance of the physical examination goal of not losing diagnosis of TAWH.
‘The Eyes of an Intellectual Vampire’: Michael Field, Vernon Lee and Female Masculinities in Late Victorian Aestheticism
Authors: Dytor Frankie
Published: June 2021

This article reframes debate on the intersections of female aestheticism and cultural dissidence by focusing on the construction of queer masculinities at the end of the nineteenth century. Looking at the diary of Michael Field (Katharine Bradley and Edith Cooper), it examines the descriptions of Vernon Lee, Clementina (‘Kit’) Anstruther-Thompson and Maud Cruttwell during the Fields’ trip to Italy in 1895. The ambivalent presentation of these figures in the diary reveals a conflicted legacy of aestheticism, centred around the inheritance, interpretation and embodiment of queer masculinity. The article argues that the Fields developed themes associated with a previous generation of male aesthetes in order to articulate gender difference between themselves and other female-bodied aesthetes. In particular, it considers how the gender-variant Fields rejected Lee, Anstruther-Thomson and Cruttwell’s trans-masculinities as perversions of their sex.
Persistent reading difficulty despite improved focus on a stimulant medication
Authors: Anderberg Emily
Published: June 2021

Specific learning disorder is a developmental disorder characterized by difficulties learning a specific academic skill (reading, written expression, or mathematics), leading to substantially reduced achievement compared to same-age peers. Attention-deficit/hyperactivity disorder is a common comorbidity. Low academic performance must not be attributable to a more general condition such as intellectual disability, lack of educational opportunity, or low language proficiency. The learning difficulties are present from the early school years. The diagnostic assessment includes standardized academic achievement testing, review of academic records, and cognitive testing to rule out intellectual disability. Treatment includes specialized multimodal educational interventions in conjunction with academic accommodations. Pharmacologic treatment of comorbid psychiatric disorders may provide indirect benefit by helping the child better access educational interventions.
A child with inattention, hyperactivity, and impulsivity
Authors: Ozdemir Sirin , Donnelly Craig L.
Published: June 2021

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that manifests in childhood with symptoms of inattention, hyperactivity, and impulsivity. The symptoms must occur in more than one setting and cause an impairment in functioning. Attention-deficit/hyperactivity disorder is one of the most common neurobehavioral disorders of childhood and may persist into adulthood. The assessment for ADHD should include a clinical history, review of information about school functioning, and assessment of common comorbid psychiatric disorders. Children with ADHD may be unaware of their symptoms, highlighting the need for collateral information from parents and teachers. Treatment may involve behavioral/psychologic interventions, educational interventions, and medications. Behavioral interventions are the first-line approach for preschool-age children, while medication treatment should be considered the first-line approach for school-aged children and adolescents. Pharmacologic treatments include stimulant and nonstimulant medications.
Repetitive throat clearing, blinking, and grimacing
Authors: Sipsock Danielle
Published: June 2021

Tourette’s disorder requires the presence of multiple motor tics and at least one vocal tic that have been present for at least one year. A tic is a sudden, rapid, recurrent, nonrhythmic motor movement or vocalization. Tics are often associated with a premonitory urge and may be temporarily suppressed. They typically begin between the age of four and six years, peak in severity in early adolescence, and then diminish. The majority of individuals spontaneously achieve remission by early adulthood. Because tic disorders commonly co-occur with psychiatric disorders, they should be screened for in every psychiatric interview. Treatment should begin with psychoeducation and focus on symptom reduction rather than remission. Behavioral interventions, including habit reversal therapy, may be considered. Medications, such as antipsychotics and alpha2 adrenergic agonists, should be considered if tics cause severe impairment and are moderate to severe.