bluuebunny/crossref_metadata_2025 huggingface dataset:
Automatic Identification of Near Stationary Traffic States Using Changepoint Detection Method
Authors: Chen Wangyong , Hu Yao , Hu Qian , Shen Qi
Published: April 2022

Near stationary traffic states are of great significance for the calibration of the fundamental diagram and the quantification of capacity variation. In this paper, based on wavelet transform and robust functional pruning optimal partitioning (RFPOP) changepoint detection, a robust and efficient method for automatic identification of the near stationary traffic states is proposed. This method first removes the noise influence of traffic flow series, divides the series automatically into multiple candidate intervals that may be close to stationary states according to the RFPOP changepoint detection method, and calculates the candidate interval characteristics. The near stationary states are then identified based on the modified Cassidy’s criterion. A case study is provided for the proposed method, and its robustness is proved in a simulation experiment. Finally, it is shown that the method of automatic identification of near stationary traffic states proposed in this paper is robust and effective.
Multimodal Urban Transportation Network Capacity Model Considering Intermodal Transportation
Authors: Zhou Jiankun , Du Muqing , Chen Anthony
Published: April 2022

Transportation network capacity is an important indicator from measuring the performance of a transportation system. Previous studies on the capacity of multimodal networks have not considered transfers between different transportation modes. In fact, because of the diversified development of the urban transportation system, travelers are no longer limited to a single transportation mode in daily travel. This paper thus proposes an improved network capacity model considering intermodal transportation in urban multimodal transportation systems. The proposed network capacity model is formulated as a bi-level programming problem, in which the lower-level model is a combined modal split and traffic assignment (CMSTA) model. The CMSTA model consists of a cross-nested logit (CNL) in the phase of mode split to account for intermodal transportation and a path-size logit (PSL) in the phase of traffic assignment to account for route overlapping. Also, we consider the flow interaction of different modes (e.g., car and bus) when they share the same links. The Barzilai–Borwein step size method is used to efficiently solve the lower-level CMSTA model (i.e., the CNL-PSL model) of which the objective function is complicated. The numerical results demonstrate the advantages and features of the proposed model. The model is also applied to a real network case to assess the network capacity of the multimodal transportation system.
Do U.S. Rail Safety Statistics Undercount Suicides?
Authors: Topel Kurt
Published: April 2022

Rail safety researchers have long suspected that U.S. accidental rail trespassing tallies include some suicides, that is, that suicides are undercounted relative to accidents. Reports issued by the Federal Railroad Administration (FRA) imply that suicides account for less than 30% of total deaths, whereas other countries show a much higher proportion of suicides, sometimes as high as 80% of total rail deaths. The purpose of the present research was to gain insight into this question by evaluating whether official manner of death determinations are correctly reflected in FRA reports. All FRA railroad fatality records for the state of Illinois for 2019 were compared with police reports, coroner/medical examiner manner of death determinations, and online media coverage. These sources indicated that less than half of official suicides were reported correctly in FRA reports and that over 50% of all fatalities were a result of suicide. It was also found that the primary reason for the considerable undercount of suicides was FRA reporting defaults and a breakdown in the process of railroads separating accidents from suicides; it was not a reluctance or delay on the part of local authorities to declare the death as intentional.
Drivers’ Visual Distraction Detection Using Facial Landmarks and Head Pose
Authors: Zhang Shile , Abdel-Aty Mohamed
Published: April 2022

Drivers’ distraction has been widely studied in the field of naturalistic driving studies. However, it is difficult to use traditional variables, such as speed, acceleration, and yaw rate to detect drivers’ distraction in real time. Emerging technologies have obtained features from human faces, such as eye gaze, to detect drivers’ visual distraction. However, eye gaze is hard to detect in naturalistic driving situations, because of low-resolution cameras, drivers wearing sunglasses, and so forth. Instead, head pose is easier to detect, and has correlation with eye gaze direction. In this study, city-wide videos are collected using onboard cameras from over 289 drivers representing 423 events. Head pose (pitch, yaw, and roll rates) are derived and fed into a convolutional neural network to detect drivers’ distraction. The experiment results show that the proposed model can achieve recall value of 0.938 and area under the receiver operating characteristic curve value of 0.931, with variables from five time slices (1.25 s) used as input. The study proves that head pose can be used to detect drivers’ distraction. The study offers insights for detecting drivers’ distraction and can be used for the development of advanced driver assistance systems.
COVID-19 effect on perioperative findings of flexible/semi-rigid ureterorenoscopic lithotripsy: A match-pair analysis
Authors: Demirci Aykut , Hızlı Fatih , Başar Halil
Published: April 2022

Purpose:

If not treated on time with proper management options, urolithiasis cause serious morphologic and functional alterations in the involved renal units. Like many other pathologies, the diagnosis, treatment, and follow-up principles of patients with urinary stones have been negatively affected by the unestimated changes in the healthcare systems dealing intensively with COVID-19 patients. In this present study, we aimed to evaluate and present the possible effects of COVID-19 infection on the ureterorenoscopic stone treatment.

Materials and methods:

Clinical and procedural characteristics of 96 patients undergoing flexible and/or rigid ureterorenoscopy because of urolithiasis between March 2020 and January 2021 were evaluated in a retrospective manner. Obtained data were evaluated after match-pair analysis in a comparative manner between cases with a positive medical history of COVID-19 infection (Group 1, n: 48) and those without any COVID-19 infection (Group 2, n: 48).

Results:

There was no statistically significant difference between the two groups of cases with respect to age, gender, associated comorbidities, and stone characteristics (p > 0.05). The mean serum creatinine level was determined to be higher in Group 1 than in Group 2 (1.15 ± 0.59 mg/dl, 0.83 ± 0.21 mg/dl, p = 0.007, respectively). Evaluation of the operative parameters revealed longer mean time from diagnosis to surgery (33.5 ± 14.27 vs 12.12 ± 6.33 days, p = 0.001), operating time, median length of stay in hospital along with higher additional intervention rates, and Clavien-Dindo complication scores again in Group 1 (p < 0.05).

Conclusion:

Our results indicate that the presence of COVID-19 infection anamnesis may affect the clinical and operative parameters of ureteroscopic stone management in cases with urolithiasis due to the possible effects of renal units damage and longer waiting time. Urologists may be aware of these unestimated problems during and after the intervention to take necessary measures for a safe and successful ureteroscopic stone removal.
Integrating Computer Prediction Methods in Social Science: A Comment on Hofman et al. (2021)
Authors: Breznau Nate
Published: April 2022

Machine learning and other computer-driven prediction models are one of the fastest growing trends in computational social science. These methods and approaches were developed in computer science and with different goals and epistemologies than those in social science. The most obvious difference being a focus on prediction versus explanation. Predictive modeling offers great potential for improving research and theory development, but its adoption poses some challenges and creates new problems. For this reason, Hofman et al. published recommendations for more effective integration of predictive modeling into social science. In this communication, I review their recommendations and expand on some additional concerns related to current practices and whether prediction can effectively serve the goals of most social scientists. Overall, I argue they provide a sound set of guidelines and a classification scheme that will serve those of us working in computational social science.
Social media, fear, and support for state surveillance: The case of China’s social credit system
Authors: Zeng Yu , Wong Stan Hok-wui
Published: April 2022

Even in authoritarian regimes that enforce vigorous information controls, netizens are still able to access fairly diverse – sometimes even sensitive – information from social media than from traditional media. We argue that this ‘breathing space’ in social media may have an indirect positive effect on regime stability via a subtle emotional channel; exposure to news on social media heightens one’s generalized fear, which in turn increases one’s demand for social controls by the state. We test our argument using an original survey that evaluates public support for China’s social credit system. We find that the support for this seemingly all-encompassing surveillance system is positively correlated with one’s generalized fear, while one’s generalized fear is positively correlated with one’s exposure to news on WeChat, the most popular social media platform in China.
A coupled experimental and numerical analysis of AA6063 friction stir welding
Authors: Shash Ahmed Y , El-Moayed Mohamed H , Abd Rabou Mahmoud , El-Sherbiny Mahmoud GD
Published: April 2022

In the present research, a coupled Eulerian–Lagrangian model is developed to predict the forces and defects produced from AA6063 friction stir welding process. Furthermore, the obtained results from the developed model were validated experimentally by performing the welding process at different rotational and welding speed values. The results revealed an appearance of tunnel defect at all welded joints with surface flash. The current model successfully predicted both defects’ evolution. Additionally, it also generated force measurements comparable to those obtained experimentally. In addition, the developed Coupled Eulerian–Lagrangian model successfully predicted the generated force and the defects during friction stir welding process with maximum error of 14% and 18%. However, it failed in predicting the tunnel positions. In terms of the tensile strength, the largest tensile strength value was at 1250rpm and 50 mm/min, whereas the lowest one was at 1000 rpm and 25 mm/min. Moreover, the fracture locations were at the advancing side of all the welded joints.
Lattice Boltzmann investigation of flow boiling in a microchannel
Authors: Wang He , Wu Suchen , Dai Hanhui , Liu Xiangdong , Zhang Chengbin
Published: April 2022

A hybrid multiphase lattice Boltzmann model is adopted to investigate the flow boiling heat transfer process in a horizontal microchannel with consideration of bubble dynamics. The flow pattern transition in a microchannel, involving single-phase flow, bubbly flow, slug flow, and contact-slug flow, is reproduced by varying the heat flux. The influencing parameters, including the liquid mass flux, the heating wall wettability, and the confinement height of channels, on dynamic bubble behaviors and heat transfer performance are discussed. The results indicate that a sequence of single-phase flow, bubbly flow, slug flow, and contact-slug flow occurs in a microchannel with increasing heat flux. Correspondingly, the dominant heat transfer mechanism experiences the liquid convection (single-phase flow), nucleate boiling (bubbly flow), the microlayer evaporation (slug flow), and the hybrid gas convection and microlayer evaporation (contact-slug flow). The increase of mass flux or confinement height extends the range of heat flux for high-efficiency bubbly and slug flow. The hydrophilic heating wall is preferred for better heat transfer performance in a microchannel due to the strengthened microlayer evaporation and less vapor occupation of the effective nucleation area.
The brake pressure change rate in brake chamber and its online monitoring in semitrailer transport vehicle for dangerous cargo
Authors: Zhao Ran , Li Gangyan , Yu Bing , Yang Fan
Published: April 2022

The electronically controlled pneumatic brake system (ECPBS) of semitrailer transport vehicle for dangerous cargo (STVDC) is required to control the brake pressure in each brake chamber accurately and stably. Accordingly, the brake pressure change rate (BPCR) in the brake chamber is taken as one of the evaluation parameters and control indicators of ECPBS for STVDC in this paper; an online monitoring implementation scheme of the BPCR in the brake chamber is designed; a simplified model is built based on AMESim and verified by hardware-in-the-loop experiments based on dSPACE; finally, the online monitoring function of BPCR in the brake chamber is validated with the simplified model. This paper provides a new idea for the design and development of ECPBS for STVDC.
DDPG-based controller of enhanced adaptive cruise control with lane-change assistance for an articulated vehicle
Authors: Zhao Weiqiang , Ma Xiaowei , Nie Zhigen
Published: April 2022

Traditional adaptive cruise control (ACC) would choose to follow when encountering low-speed cars in front, but this may lead to low driving efficiency. This paper proposes a controller of enhanced adaptive cruise control with lane-change assistance (LCACC) for an articulated vehicle. A two-layer hierarchical control structure is adopted in this study. The upper determines high-level commands, while the bottom consisting of two modified deep deterministic policy gradient (DDPG) networks, controls the steering wheel and throttle/brake, respectively, according to the commands made by the upper layer. The vehicle’s lateral and longitudinal control are decoupled and controlled by two modified DDPG networks. Through proper design of the state and reward function, the actions of the articulated vehicle such as steering and acceleration/braking are closer to those of humans, thus ensuring ride comfort. Compared with traditional ACC, the LCACC proposed in this study increases the driving efficiency of the articulated vehicle by an average of 16% when there is a low-speed lead car.
Path tracking of autonomous vehicle based on adaptive preview trajectory planning with the consideration of vehicle stability
Authors: Qiu Bin , Wei Lingtao , Wang Xiangyu , Li Liang , Zhou Daolin , Wang Zhenfeng
Published: April 2022

The path control gives the target path through planning, and uses the tracking strategy to make the vehicle converge to the target path. How to balance the tracking performance and the vehicle stability is a crucial and worthy research for the autonomous vehicle safety. In this paper, a hierarchical path control strategy consists of path planning and tracking with the consideration of vehicle lateral stability is proposed. In the adaptive preview distance block, the preview distance is adaptively regulated according to the vehicle speed, sideslip angle, and the preview trajectory curvature to balance the tracking error and stability. In the path planning block, the three-order polynomial fitting method is adopted to give the desired path according to the preview distance and the relative position relationship between vehicle and road or obstacles. The linear quadratic regulator (LQR) controller is designed to tracking the desired path fully using the previewed curvatures and the vehicle motion error. The hardware in the loop (HIL) simulation and vehicle test results illustrate that the proposed strategy can deal with path tracking, avoidance and lance change scenes in low computation burden, and maintain the stability of vehicle simultaneously.
H∞ controller design for singular Markov jump systems with time-delays
Authors: Zhou Juan , Lai Huiling , Liu Cuoyi , Men Bo
Published: April 2022

In this article, the [Formula: see text] control problem of a class of singular Markov jump systems with time-varying inputs and state delays is investigated. Based on the Lyapunov stability theory, by constructing a different Lyapunov–Krasovskii functional, the sufficient conditions of being stochastic stable and having H∞ performance index are given. Then, the design method of state feedback controller is given to ensure the closed-loop system is stochastic stable and has [Formula: see text] performance index. Finally, simulation examples are given to verify the effectiveness of the proposed methods.
Adaptive sliding mode-based active disturbance rejection control for vehicle suspension control
Authors: Suhail Suhail Ahmad , Bazaz Mohammad Abid , Hussain Shoeb
Published: April 2022

This article presents an adaptive sliding mode-based active disturbance rejection control strategy for the quarter car active suspension control. The suspension system is problematic for its nonlinearities from the dampers, springs, and irregular excitation from the road surface. This study considers this complex behavior and nonlinear characteristics of the suspension system and uses an adaptive sliding mode control law and an extended state observer to estimate and eliminate them from the controlled system. The central concept is to combine the advantages of adaptive sliding mode control to accurately track the reference trajectory with the ability of active disturbance rejection control to reject the parameter uncertainties and external disturbances. The proposed control scheme is verified in simulation studies with parameter uncertainties, nonlinearities, and external disturbances. The simulation results show that the proposed control scheme can significantly improve vehicles’ ride comfort and road-handling ability, owing to the extended state observer’s estimation capability. A comparison of the proposed strategy is also presented with a linear active disturbance rejection control and a conventional proportional–integral–derivative controller. Simulation results show that adaptive sliding mode-based active disturbance rejection improves the robustness against modeling errors, nonlinearities, and disturbances.
Perception of Employees Regarding the Quality Management System Implemented at a Tertiary Care Eye Hospital in North India: A Mixed-Methods Study
Authors: Dubey S. , John D. , Arora A K , Mathur Umang , Singh A K
Published: April 2022

Background:

Quality management in healthcare is critical for hospitals and everyone in the loop —from physicians to support staff—needs to be aware of and involved in this process.

Objectives:

To assess the perception of employees about the quality management system (QMS) implemented at a tertiary care eye hospital in north India and to use it to identify scope for further improvement.

Methods:

This cross-sectional mixed-method study involved both questionnaire-based survey and an in-depth interview by a third party. The questionnaire had 12 questions to assess the changes in culture, infrastructure, environment, system, operation theatre and outpatient department. Employees shared their opinion about improvements brought by the QMS in eight years. Respondents were divided into five groups based on their job description: (i) doctors, (ii) technical staff (nursing/operation theatre/laboratory), (iii) optometrists/opticians/audiologists, (iv) patient care executives and (v) human resources/administration/others.

Results:

Of the 73 employees interviewed, 94.5% perceived an improved treatment and care process and 91.8% perceived improved treatment results. According to 83.6% of the employees, they were encouraged to report patient safety concerns and 71.2% saw improved incidence and adverse event management. The QMS has increased patient satisfaction according to 83%, while 91.8% felt it improved the profile of the hospital. The employees stated no negative effects of the QMS except a long waiting time of the patients and the duplication of paperwork.

Conclusion:

QMS has brought many positive changes across the hospital. Still, there is scope to reduce the patient waiting time and paperwork duplication.
Constitutive modelling of a self-healing composite matrix polymer material
Authors: Ivica Smojver , Darko Ivančević , Dominik Brezetić , Tatjana Haramina
Published: April 2022

In this work, a constitutive model of an intrinsically self-healing composite matrix material is presented. The developed model comprises a micro-damage initiation and evolution model, and a healing evolution model, which are combined with the von Mises linear isotropic hardening plasticity. It is implemented into the Abaqus/Standard user material subroutine UMAT and validated using experimental results of static tensile and two-cycle tensile tests performed on partially neutralised poly(ethylene-co-methacrylic acid) (EMAA) ionomer copolymer, Surlyn® 8940. In the development of the model, Continuum Damage Healing Mechanics (CDHM) concepts of nominal and healing configurations are used. In addition, these concepts are used along with the strain equivalence hypothesis to streamline the numerical implementation. The strain equivalence hypothesis relates strain and stress tensors in the nominal and the healing configuration. Finally, successful validation has shown that the developed model is able to accurately predict behaviour of Surlyn® 8940 coupons during tensile tests and it can precisely predict the accumulation of plastic strain.
Understanding Contextual and Personality-Related Factors Predicting Student Career Certainty in Work Placement Learning
Authors: Okorie Cornelius Ofobuisi , Nwankwo Felix Monday , Iwuala Harrison Onuwa , Okolie Ugochukwu Chinonso
Published: April 2022

This study builds on the social cognitive career theory model of career self-management (SCCT-CSM) to examine the effects of faculty-based supervisor informational support, parental instrumental support and classmate emotional support on student career certainty during work placement learning. It also examined the mediating effects of self-esteem and career decision self-efficacy in the relationships. Using data collected at three-time points from undergraduate students undertaking work placement learning in 109 Nigerian organizations, we test an SCCT-CSM-driven model of contextual factors (i.e. supports), core SCCT variable (self-efficacy), personality-related variable (i.e. self-esteem) and career-related action (i.e. student career certainty) in work placement learning context. The results suggest that perceiving higher informational and instrumental support from faculty-based supervisors and parents stimulated students’ career decision self-efficacy and self-esteem in learning career-related skills, consequently leading to higher student career certainty. The findings have important implications for faculty-based placement learning supervisors, parents, students and placements host organizations to acknowledge the role of support in enhancing student career certainty. Thus, support should be highly considered during work placement learning to improve student career certainty.
Nonlinear frequency behavior of cracked functionally graded porous beams resting on elastic foundation using Reddy shear deformation theory
Authors: Forghani Mohammadamin , Bazarganlari Yousef , Zahedinejad Parham , Kazemzadeh-Parsi Mohammad Javad
Published: April 2022

This paper presents the nonlinear frequency behavior of cracked functionally graded porous beams subjected to various boundary conditions using Reddy shear deformation theory and Green’s tensor together with the Von Karman geometric nonlinearity. The material properties of the beam vary exponentially in thickness direction. A generalized differential quadrature method (GDQM) in conjunction with a direct numerical iteration method is developed to solve the system of equations derived by means of Hamilton’s principle. Demonstrating the convergence of this method, the verification is performed by using extracted results from a previous study based on the Euler and Timoshenko beam theory. The results for extensive studies are provided to understand the influences of the different gradient indexes, vibration amplitude ratios, porosity indexes, shear and elastic foundation parameters, and boundary conditions on the nonlinear frequency behavior. The location of crack plays the significant role on the nonlinear frequency ratios. The frequency ratios hit the minimum when the crack is located in mid-span of the beam. In this regard, the effect of shear stiffness of foundation is much more than that of Winkler one in the increasing mid-span value of nonlinear frequency ratio. It is also shown that the crack location results in decline of frequency ratios in the mid-span of beam specially for the cracks located closer to surface, the deeper ones lead to get nonlinear frequency ratios rise much more due to the fact that the deeper the crack is, the weaker the crack section becomes. The results of this paper and the effects of these parameters can be used in the optimal design of functionally graded beams and in crack prediction, detection, and monitoring techniques.
The energy release rate for non-penetrating crack in poroelastic body by fluid-driven fracture
Authors: Kovtunenko Victor A , Lazarev Nyurgun P
Published: April 2022

A new class of constrained variational problems, which describe fluid-driven cracks (that are pressurized fractures created by pumping fracturing fluids), is considered within the nonlinear theory of coupled poroelastic models stated in the incremental form. The two-phase medium is constituted by solid particles and fluid-saturated pores; it contains a crack subjected to non-penetration condition between the opposite crack faces. The inequality-constrained optimization is expressed as a saddle-point problem with respect to the unknown solid phase displacement, pore pressure, and contact force. Applying the Lagrange multiplier approach and the Delfour–Zolésio theorem, the shape derivative for the corresponding Lagrangian function is derived using rigorous asymptotic methods. The resulting formula describes the energy release rate under irreversible crack perturbations, which is useful for application of the Griffith criterion of quasi-static fracture.
A general contact stiffness model for elastic bodies and its application in time-varying mesh stiffness of gear drive
Authors: Wang Hongbing , Zhou Changjiang , Lv Yunyan , Hu Bo
Published: April 2022

As a critical element of time-varying mesh stiffness (TVMS), contact stiffness of a gear drive has been defined based on simplified Hertzian contact stiffness or semi-empirical nonlinear Hertzian contact stiffness in previous works. This study proposes a general contact stiffness model for elastic bodies through piecewise linear interpolation of contact pressure. The TVMS of a spur gear drive is determined through potential energy method and proposed contact stiffness model verified by Hertzian contact theory and finite-element method. Then, the influence of applied load on contact stiffness is studied, and the differences among proposed contact stiffness, simplified Hertzian contact stiffness, and nonlinear Hertzian contact stiffness are analyzed. Results show that contact stiffness increases with the applied load, and the TVMS based on the proposed contact stiffness model is the smallest among the three contact stiffness models. Effects of tooth width and input torque on the TVMS are further discussed. The TVMS becomes bigger with increased tooth width and input torque, but the increase rate decreases as tooth width or input torque increases. These findings indicate that reasonable matching of design parameters is beneficial for increasing load capacity and optimizing the dynamic performance of gear systems.
Phenomenological Origins of Psychological Ownership
Authors: Khan Haider Riaz , Turri John
Published: April 2022

Motivated by a set of converging empirical findings and theoretical suggestions pertaining to the construct of ownership, we survey literature from multiple disciplines and present an extensive theoretical account linking the inception of a foundational naïve theory of ownership to principles governing the sense of (body) ownership. The first part of the account examines the emergence of the non-conceptual sense of ownership in terms of the minimal self and the body schema—a dynamic mental model of the body that functions as an instrument of directed action. A remarkable feature of the body schema is that it expands to incorporate objects that are objectively controlled by the person. Moreover, this embodiment of extracorporeal objects is accompanied by the phenomenological feeling of ownership towards the embodied objects. In fact, we argue that the sense of agency and ownership are inextricably linked, and that predictable control over an object can engender the sense of ownership. This relation between objective agency and the sense of ownership is moderated by gestalt-like principles. In the second part, we posit that these early emerging principles and experiences lead to the formation of a naïve theory of ownership rooted in notions of agential involvement.
Feasibility and safety of guidewire-balloon entrapment technique for recanalization of thoracic central vein occlusion in hemodialysis patients
Authors: Bai Yafei , Liang Shuntian , Vachharajani Tushar J. , An Na , Xu Mingzhi , zhou Zhongxin , Li Hong
Published: April 2022

Objective:

To explore the feasibility and safety of Guidewire-Balloon Entrapment Technique (GBET) for the recanalization of thoracic central vein occlusions (TCVOs) in hemodialysis patients.

Methods:

A retrospective observational study was conducted using data from 28 patients who required the establishment or maintenance of hemodialysis access and were treated with GBET for the recanalization of right-sided TCVOs from January 2017 to April 2021. Of the patients, 27 required tunneled cuffed catheter (TCC) placement or exchange, and 1 had an outflow tract occlusion of the Brescia-Cimino radio cephalic arteriovenous fistula (AVF).

Results:

A total of 26 patients successfully underwent TCC exchange and placement using GBET; 1 patient underwent successful recanalization of an occlusion of the outflow tract of the right Brescia-Cimino AVF; and 1 patient underwent successful TCC placement in the left internal jugular vein (LIJV) after the failure of TCC placement in the right internal jugular vein (RIJV). The success rate for GBET was 27/28 (96.43%), and there were no major complications.

Conclusion:

GBET is a safe and effective method for the recanalization of right-sided TCVOs, especially for TCC exchange and placement, and can be used as a safe and easy approach for TCVO recanalization.
Exosomal miRNA-200b-3p regulated autogenous arteriovenous fistula thrombosis in maintenance hemodialysis patients
Authors: Luo Minhong , Mo Caiju , Tang Dang , Liu Sheng zi , Yang Tiecheng
Published: April 2022

Background:

Autogenous arteriovenous fistula (AVF) is the best vascular hemodialysis access for terminal chronic renal failure patients but is prone to thrombosis. Pathogenic mechanisms of AVF thrombus are thus largely explored. As exosomes carry genetic content from cell of origin. We hypothesized that miRNAs in serum exosomes are promising regulators of AVF thrombosis.

Methods:

Serum exosomes were isolated from maintenance hemodialysis (MHD) patient, miRNAs profile of the exosomes was obtained by high throughput sequencing, six miRNAs (miR-144-5p, miR-18a-5p, miR-200a-3p, miR-200b-3p, miR-141-3p, and miR-429) were determined as candidates examined by RT-PCR, cells transfected with miR-200b-3p mimics demonstrated significantly increased mRNA levels of VEGF and Ang-II, the relationship between miR-200b-3p and VEGF or Ang-II was performed by adual luciferase reporter assay.

Results:

There are 43 miRNA down-regulation and 15 miRNA up-regulation between MHD group and MHD+Thrombus group, the expression levels of miR-200b-3p and miR-429 in MHD with thrombus were significantly increased ( p < 0.001, p < 0.05). Inhibited miR-200b-3p expression level can increase VEGF mRNA and protein expression levels and decrease Ang-II mRNA and protein expression levels. Furthermore, we also identified that miR-200b-3p targets VEGF and Ang-II.

Conclusion:

Our study indicates that serum exosome-derived miR-200b-3p regulate VEGF and Ang-II to increase intimal hyperplasia to induce AVF thrombosis. Besides miR-200b-3p, miR-200 family may also play a regulatory role in AVF thrombosis.
The Relationship of Circulating Proprotein Convertase Subtilisin/Kexin Type 9 With TSH and Lipid Profile in Newly Diagnosed Patients With Subclinical and Overt Hypothyroidism
Authors: Sadik Noha Adly , Rashed Laila Ahmed , El-Sawy Shereen Sadik
Published: April 2022

Introduction:

Overt and subclinical hypothyroidism are mostly associated with dyslipidemia, an essential cardiovascular risk factor. Recently, thyroid stimulating hormone (TSH) was identified to have a direct role on lipid metabolism via increased expression of hepatic proprotein convertase subtilisin/kexin type 9 (PCSK9). PCSK9 plays a crucial role in lipid metabolism via regulating LDL-C levels. Thus, we aimed to evaluate circulating PCSK9 levels and to assess its relationship with serum TSH and lipids in newly diagnosed patients had overt and subclinical hypothyroidism.

Methods:

In our study, we enrolled 60 newly diagnosed untreated patients with overt and subclinical hypothyroidism and 30 euthyroid subjects served as the control group. Serum TSH, FT4, FT3, lipid profile and circulating PCSK9 levels using ELISA kits were measured in all subjects. Our data were summarized using mean ± SD or median and interquartile range. Correlations between PCSK9 expression levels and different variables were done using Spearman correlation coefficient.

Results:

Circulating PCSK9 median levels were significantly increased in patients had overt and subclinical hypothyroidism (12.45 ng/ml, 7.50 ng/ml respectively) compared to the control group (3.30 ng/ml) ( P < .001). Circulating PCSK9 levels significantly correlated positively with TSH, total cholesterol, triglycerides, and BMI, and negatively correlated with FT4 and FT3 among all studied subjects. Using multivariate regression analysis TSH was the only significant independent predictor of circulating PCSK9 ( P < .001).

Conclusion:

Our results supports the new implication of TSH in lipid metabolism via the significant association with PCSK9. Whether this relationship between TSH and PCSK9 is a cause or just an association needs further evaluation.
Developmental competencies, temperament, parenting practices and psychosocial adversities in children with internalising disorders – A pilot study
Authors: Viswanathan Poornima , Kishore MT , Seshadri Shekhar P , Binu VS
Published: April 2022

Research on the aetiology of internalising disorders has focussed on biological and environmental factors, however, the role of developmental competencies that a child acquires has not been explored much. The current report aimed to understand the association among the developmental competencies, temperament, parenting practices and psychosocial adversities in internalising disorders. The sample consisted of 30 children and adolescents with internalising disorders belonging to the age group of six to 18, and one of their parents. All the participants were assessed for functional impairment, temperament, interpersonal competence, emotion regulation, executive function, self-concept, adaptive behaviour, parenting practices, life events and family environment using standardised tools. The findings revealed that positive parenting shares a negative relationship with functional impairment(ρ=−0.62; p <.001). On comparison with non-clinical samples in previous studies, interpersonal competence and self-concept were found to be at lower levels in the current sample. In conclusion, the current study indicates that children with internalising disorders differ from control groups in specific developmental competences. These findings have specific implications for intervention and research in the area of internalising disorders in children and adolescents.
Advance care planning: End-of-life hopes and fears among community dwelling adults
Authors: Dark-Freudeman Alissa , Bensadon Benjamin A
Published: April 2022

End-of-life (EOL) medical care in the United States often does not align with patients’ goals and preferences. This study explored EOL hopes and fears among 86 community-dwelling adults and examined medical and psychological predictors of death anxiety. Common EOL hopes included absence of suffering, closure, and personal fulfillment. Common EOL fears included suffering, lack of competence, and specific types of death. Fear of the dying process was greater than fear of death itself. Health predicted death anxiety; age alone, did not. Advance care planning and clinical decision making should include these psychological insights and explicitly address EOL hopes and fears.
Decay characteristics of aerosolized viruses in the air and control strategy of thermal and humid environment for epidemic prevention
Authors: Yang Zhao , Wang Qingqin , Zhao Li , Long Enshen
Published: April 2022

The novel corona respiratory viruses usually leave the host via droplets and float in the air or settle down. Medically, the decay characteristics of aerosolized viruses have been simulated and measured by atomizing suspensions into air, but there has been no systematic study on the effect of ambient temperature and humidity. In this study, we collected experimental data from existing medical studies, then introduced and calculated the initial decay constant (k1) and the secondary decay constant (k2) based on these data as a unified standard to quantify the decay process of the aerosolized viruses. Additionally, the influence of various factors on the decay constant of respiratory viruses in the air was statistically analyzed. The results showed that the phase decay of aerosolized viruses was very evident, and k1 (0.1∼50) was usually one order of magnitude higher than k2 (0.005∼3.2). Furthermore, the relationship between the decay constant and the survival rate of viruses, representing the risk of virus transmission, and the decay time constants, reflecting the effective period of prevention and control, was discussed. According to the decay law, the main contradiction between virus transmission and epidemic prevention and control at different time nodes was pointed out, and scientific measures to reduce the transmission risk in the built environment were recommended.
Towards a politics of collaborative worldmaking: ethics, epistemologies and mutual positionalities in conflict research
Authors: Vogel Christoph , Musamba Josaphat
Published: April 2022

Scholarly engagement with ethics, epistemologies and positionalities dilemmas in conflict research is marked by a disconnect between self-referential debates in the Ivory Tower and the very places research takes place. If there is reflection on foreign researchers, research brokers or research participants, accounts of genuinely collaborative work are rare. Drawing from a decade of collaborative research in eastern Congo, our essay targets this gap by critically discussing challenges we faced and lessons we learned with regards to our mutual positionalities. In so doing, we join debates calling for situated reflection on ethnography in and of conflict zones. Based on our research experience, we contend that a fully joint approach – including planning, execution, analysis and writing – can be an avenue toward decolonizing our ethics and epistemologies. Moreover, we argue for a pluriversal ethics that accounts for context and positionalities of the involved researchers and allows for collaborative worldmaking.
The global rhythms of consumption practices
Authors: Rosenthal Benjamin , Brito Eliane Pereira Zamith
Published: April 2022

Although consumers’ temporal experiences in the performance of single practices of extraordinary nature have been well understood, there is not yet a clear understanding of how temporal experiences unfold from the recurrent performance of complexes of practices. Conversely, we delve into how the recurrent performance of quotidian complexes of practices affects consumers’ temporal experiences. To do so, we adopt a Rhythmanalysis lens to study the recurrent performance of runners and swimmers. We contribute to the literature by proposing that global rhythms are enduring and encompassing temporal experiences unfolding from the recurrent performance of complexes of practices through a process involving the orchestration of complexes of practices, the embodied effects of its routinization, the integration of consumption habits, and social involvement with communities of practitioners.
Experiences of intimate continence care and the impact on the family dyad relationship for people living at home with dementia and their co-resident family members
Authors: Cole Laura , Drennan Vari M , Manthorpe Jill , Hatzidimitriadou Eleni , Iliffe Steve
Published: April 2022

Objectives

The experience of providing/receiving intimate continence care between family members can be difficult and emotive. Often, for people living with dementia this seems an area of care overlooked by professionals. This study investigated the experiences of intimate continence care for people living with dementia and their family member (the family dyad), and whether they viewed this as impacting on their relationship.

Method

Face-to-face interviews were conducted at 6 monthly intervals over a 12-month period with 13 carers (all family members) and one person living with dementia (13 family dyads) in England. Interviews were recorded and transcribed. Analysis of the data was achieved using a descriptive phenomenological method.

Findings

Carers’ attitudes towards providing intimate continence care revealed a task-focused approach for some but feelings of disgust and distress for others. Four participants (including the participant living with dementia) reported that intimate continence care had strengthened their dyad relationship. However, some carers perceived the care and support received from health and social care practitioners to be insufficient, which placed extra stress on them and adversely affected their family dyad relationship.

Conclusion

Implications of the study suggest that integrated and effective continence care and support for people living with dementia and their carers could (1) maintain the quality of the family dyad relationship, (2) help keep the person living at home, delaying an unwanted move to a care home and (3) consequently improve overall quality of life for individuals in the family dyad. Assuring integrated and effective continence care should be a priority for service funders and quality assurance regulators.
Water entry dynamic analysis of lightweight sandwich plates with lattice core: A semi-analytical approach and comparative study
Authors: Wang Hao , Gan Lin
Published: April 2022

This is the third part of water entry hydro-elastic analysis of clamped sandwich plates with lattice core (CSPLC). In the first and second parts analysis, the engineering prediction model is built to estimate the dynamic responses of CSPLC. To discuss the responses of CSPLC in more detail, the objective of the present work is to investigate the hydro-elastic responses of rectangular, clamped sandwich plates with lattice core (CSPLC) subjected to water entry via combined a novel semi-analytical approach and multi-physical numerical simulation. In the theoretical approach, the hydro-elastic characteristics are quantified by coupling a hydrodynamic water entry model with a first shear displacement model of elasticity for CSPLC. The fluid-structure interaction (FSI) effects of water entry are taken into account by dividing the total impact pressure into the rigid water entry pressure and the interacting pressure. To capture the precise responses of CSPLC, both the global displacement field and the local displacement field are considered in the analytical model. The dynamic governing equations are derived from the energy variation principle and solved by employing the modal approach. Furthermore, the 3D FSI finite element simulation is carried out to get the detailed hydro-elastic characteristics of CSPLC. This engineering semi-analytical model is found to yield accurate results for dynamic responses and offers significant savings in computational cost compared to the FSI simulations. As a comparative study, for a same geometrical stiffened panel, the FSI impact pressure and structural deflection are also given respectively.
Research on wave suppression mechanism of porous baffle based on vortex dynamics
Authors: Shen Minmin , Sun Chuanbin , Tong Baohong , Hu Xiaolei
Published: April 2022

The exciting force generated by the violent sloshing of the fluid in the tank will damage the tank structure and even affect the attitude stability of a vehicle. Hence, this study constructs a numerical model and horizontal excitation experimental platform. Taking the porous baffle in the tank of a specific type of tanker as an example, the current study analyses the impact pressure response law at different frequencies. On the basis of vortex dynamics, this work explores the evolution mechanism of the vortex flow structure under different excitation amplitudes and frequencies. The exploration reveals the law of dimensionless vortex intensity and energy change. In addition, the relationship between vortex intensity and wall pressure is determined. Studies have shown that the non-linear violent sloshing causes the resonance frequency of the tank to deviate from the natural frequency. When the excitation amplitude intensifies, the range and strength of the vortex structure and the distance from the vortex core to the baffle increase. In such circumstance, the accumulation and dissipation of energy are more evident. In addition, when the excitation frequency is closer to the resonance frequency, the distance between the vortex core and the baffle widens. Moreover, the energy intensity around the baffle increases as the frequency increases. The time history of wall pressure P and vortex intensity Q shows a certain regularity, and the ratio of Pmax to Qmax decreases with the increase of the excitation frequency.
An improved algorithm for liner impedance eduction in low signal-to-noise ratio flow duct
Authors: Zhang Penglin , Yang Cheng , Huang Yu
Published: April 2022

The impedance eduction technique is widely used by the aeroacoustics community to obtain liner property in a flow duct. However, the obtained impedance is often found to be discontinuous in the frequency domain which violates theoretical liner models. The low signal-to-noise ratio (SNR, in dB) is one factor leading to this unexpected result. To overcome this, a weighting coefficient, represented by an SNR dependent sigmoid function with two control parameters, is introduced to the cost function in the iteration process. The proposed algorithm is employed to measure the impedances of two liners and results show an improvement in the smoothness of the resultant impedance curves over those obtained from conventional cost function.