bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Finite Element Simulation Study on the Properties of a Multi-Material Based Auxetic Metamaterial
Authors: Su Yutai , Wu Xin , Shi Jing , Wang Jin 
Published: January 2020

Abstract
Auxetic metamaterials have unique structural designs exhibiting zero or negative Poisson’ ratios during stretch/compression processes, which enable many critical applications such as sensing technology, wearable devices, and weight reduction parts. However, it is difficult to achieve ideal performance of various structural designs through geometry manipulation due to the beam/wall buckling under large strain. One way to minimize the occurrence of buckling is by introducing the high elasticity on the joints, but trade-offs exist among different mechanical behaviors. To this end, this study proposes to use a multi-material combining with the structure optimization to design an auxetic structure. The basic re-entrant structure is employed due to its simplicity, and finite element method (FEM) is adopted to demonstrate the effectiveness of this newly proposed strategy regarding the auxetic behaviors. For this multi-material structure, a different Young’s modulus is designed to apply on the additional arch structure. A series of simulations, which consider the influence of the mechanical properties, are conducted to investigate the change of auxetic behaviors such as stress distribution, Poisson’s ratio, and equivalent Young’s modulus against the applied material properties. The results indicate that the mechanical properties are strongly affected by the geometry design and the applied materials properties. Meanwhile, the buckling effect of the beam/wall could be eliminated if the hinge strength is small enough. The trade-off between equivalent mechanical properties and Poisson’s ratio could also be tuned through this newly material-based design.
Effects of Extrusion Temperature and Printing Direction in Bioprinting on Profile Accuracy of 3D Printed Constructs
Authors: Thakare Ketan , Wei Xingjian , Qin Hongmin , Pei Zhijian 
Published: January 2020

Abstract
In extrusion-based bioprinting, 3D printing process parameters affect dimensional accuracy of printed constructs. However, little information is currently available on effects of extrusion temperature and printing direction on dimensional accuracy of 3D printed constructs using Alginate:Methylcelluolose hydrogel. In this study, strand thickness of 3D printed constructs printed at temperature of 35°C, 40°C, 45°C and at vertical and horizontal printing direction were measured. The statistical analysis revealed that extrusion temperature and printing direction have significant effect on the strand thickness of 3D printed constructs.
A New Incremental Harmonic Balance Method With Two Time Scales for Quasi-Periodic Motions of an Axially Moving Beam With Internal Resonance Under Single-Tone External Excitation
Authors: Huang Jianliang , Zhu Weidong 
Published: January 2020

Abstract
In this work, a new incremental harmonic balance (IHB) method with two time scales, where one is a fundamental frequency, and the other is an interval distance of two adjacent frequencies, is proposed for quasi-periodic motions of an axially moving beam with three-to-one internal resonance under singletone external excitation. It is found that the interval frequency of every two adjacent frequencies, located around the fundamental frequency or one of its integer multiples, is fixed due to nonlinear coupling among resonant vibration modes. Consequently, only two time scales are used in the IHB method to obtain all incommensurable frequencies of quasi-periodic motions of the axially moving beam. The present IHB method can accurately trace from periodic responses of the beam to its quasi-periodic motions. For periodic responses of the axially moving beam, the single fundamental frequency is used in the IHB method to obtain solutions. For quasi-periodic motions of the beam, the present IHB method with two time scales is used, along with an amplitude increment approach that includes a large number of harmonics, to determine all the frequency components. All the frequency components and their corresponding amplitudes, obtained from the present IHB method, are in excellent agreement with those from numerical integration using the fourth-order Runge-Kutta method.
Development of Vehicle Safety Rating Systems and Application to Off-Road Vehicles
Authors: Kebschull Scott A. , Van Auken R. Michael 
Published: January 2020

Abstract
The first vehicle safety rating systems were the US National Highway Traffic Safety Administration’s New Car Assessment Program (NCAP), started in 1979, and the Australasian NCAP, started in 1992. These systems were investigated in order to determine the methods used to develop them and the characteristics that make them scientifically valid. In addition, a proposed safety rating system for All-Terrain Vehicles (ATVs) and Side by Side Vehicles (SSVs) was compared to the automotive NCAP systems in order to determine its scientific validity. The literature related to the history and development of the original NCAP safety rating systems was reviewed. The proposed safety rating system for ATVs was also reviewed and comparisons with the original NCAP systems were made. The original NCAP systems have been based on correlations between the measured acceleration of the head and chest and actual injury outcome probabilities. These systems also were intentionally restricted to providing comparisons between vehicles of similar mass. Based on this premise, criteria for the establishment of a vehicle safety rating system have been developed with the aim to ensure that such a system has validity and provides ratings that are based on scientifically established correlations between objectively and repeatably measured values and desirable safety outcomes. The proposed safety rating system for ATVs and SSVs that was not developed following this method was found to have no basis in known relationships between the test outcomes and injury probabilities. Although the proposed safety rating system for ATVs and SSVs was found to be unacceptable, a methodology for developing a safety rating system that would meet the criteria is proposed. The methodology would involve collecting real-world injury and exposure data and correlations with measurable vehicle characteristics. This correlation could then lead to the development of scientifically valid safety rating systems for ATVs and SSVs.
Experimental and Numerical Investigation of Dynamic Impact on Universal Breakaway Steel Post
Authors: Mehrmashhadi Javad , A. Pajouh Mojdeh , Reid John D. 
Published: January 2020

Abstract
A closed guardrail system, known as “bullnose” guardrail system, was previously developed to prevent out-of-control vehicles from falling into the elephant trap. The bullnose guardrail system originally used Controlled Release Terminal (CRT) wood posts to aid in the energy absorption of the system. However, the use of CRT had several drawbacks such as grading and the need for regular inspections. Universal Breakaway Steel Post (UBSP) was then developed by the researchers at Midwest Roadside Safety Facility as a surrogate for CRT. In this study, the impact performance of UBSP on the weak-axis and strong-axis was studied through numerical modeling and component testing (bogie testing). A numerical model was developed using an advanced finite element package LS-DYNA to simulate the impact on UBSP. The numerical results were compared to experimental data. Further research on soil models was recommended. The numerical model will be used to investigate other applications for UBSP such as the Midwest Guardrail System (MGS) long span system, guardrail end terminal designs, or crash cushions.
Effects of Absorbed Moisture Content on the Impact Response of Specially-Orthotropic Composite Plates
Authors: Ahmad Furqan , Abbassi Fethi , Miran Sajjad 
Published: January 2020

Abstract
This paper addresses the hygroscopic effects on the impact response of specially-orthotropic carbon fiber reinforced polymer composite plates under low-velocity impact loading. The material used in this study is Toray T800/3900 which is consist of carbon fibers and epoxy resin. For different percentage of moisture content by weight in the composite plates, low-velocity impact tests were done by using the 8-ply unidirectional [UD] and cross-ply [CP] composite plates with newly designed mini-drop tower testing machine. To study the hygroscopic effects, specimens were impacted by constant weight of impactor (3.44 Kg) with fixed impact height of 0.70 m corresponding to 23.62 J impact energy. The experiments were carried out on plates with dimension of 125 mm × 125 mm × 1.5 mm for simply supported boundary conditions. All UD composite plates were broken into two parts, but the impactor bounces back after hitting the top layer of the CP composite plate for all conditions. The strength of the UD composite plates decreased with increase of moisture contents, but with the increased of moisture contents, a small change was observed in the peak force, time to peak force values and absorbed energy for the CP composite plates. The large size damage areas were observed for wet plates as compared to dry plates. Absorbed moisture contents also have effect on the impactor velocity and impactor displacement.
Flexible Valveless Pump for Bio Applications
Authors: Naghdi Masoud , Farzbod Farhad , Goggans Paul M. 
Published: January 2020

Abstract
In electromechanical actuators Lorentz force law is used to convert electrical energy into rotational or linear mechanical energy. In these conventional electromechanical actuators, rigid wires conducts the electrical current and as such the types of motion generated by these actuators are limited. Recent advances in liquid metal alloys permit designing electrical wires that are stretchable. These flexible wires have been used to fabricate various flexible connections, sensors and antennas. However, there have been very little efforts to use these stretchable liquid metal wires as actuators. Building upon our previous work in this area, we have made a flexible pump which can be used in bio applications. In this design we placed a flexible polymeric substrate filled by liquid metal Galinstan between two permanent magnets. Since the pump should convey the biological cells suspended along the fluid flow, utilizing check valves may increase the risk of clog in the inlet or outlet. Therefore, our design is based on the nozzle/diffuser concept. This new pump can be considered as a peristaltic and valve-less mechanical pumps which utilizes the Lorentz force law as the actuating mechanism.
Assessment and Characterization of Hybrid Mesoporous Material MCM With Titanium Dioxide for Water Treatment
Authors: Xu Jiajun 
Published: January 2020

Abstract
In the current study, a new method was developed to synthesize the hybrid mesoporous material with metallic oxides, MCM-48 with TiO2, at an improved efficiency and reduced cost. The results have shown an over 95% adsorption efficiency for trace metals for the hybrid MCM-48 with TiO2 materials, and a significantly improved maximum adsorption capacity compared to pure MCM-48. Its unique hybrid structured allows the polluted water to pass through the strong yet highly permeable structure of mesoporous material, while gives enough time for the pollutants to react with the TiO2 infused on the porous structure so that the polluted water can be treated without introducing secondary pollutants. The microstructures of the MCM-48 with and without TiO2 are characterized using SEM with EDS and Porosimiter. The effectiveness of wastewater treatment is measured using Inductively Couple Plasma-Mass Spectrometer (ICP-MS). The significant improvements observed here is likely due to the infused TiO2 to the base MCM-48 structure, which also agree with the authors’ previous finding. It is noticed that, while the higher concentration of TiO2 has a positive impact on the adsorption of trace metals, the higher concentration of Ti source does not necessarily yield significantly higher concentration of TiO2 in the final product. Future study is needed to further explore this hybrid mesoporous material for other pollutants treatment, and to obtain a further understanding of its mechanisms.
Carpal Tunnel Injury in Automobile Collisions
Authors: Wiechel John , Morr Douglas , Boggess Brian , Amenson Tara 
Published: January 2020

Abstract
It is trite to say that automobile collisions cause injury due to mechanical force application to the body. It is also understood that carpal tunnel syndrome is a debilitating condition which is caused by mechanical forces applied to the structures of the wrist. With the increased incidence of carpal tunnel syndrome in the 1990’s, automobile accidents have been identified as a cause of carpal tunnel syndrome. Such relationship is often based on a patient’s complaints after the accident and lack of complaint before the accident. Regardless of the patient’s complaint history, a mechanical relationship between the forces present in the accident and the injury must exist. A number of vehicle accident configurations are investigated, and the forces applied to the vehicle occupant’s wrist are identified. The directions and magnitudes of these forces are discussed with respect to their relationship to carpal tunnel syndrome. This analysis shows that in low energy collisions (delta V &lt; 16 kph,10 mph) the forces necessary to cause carpal tunnel syndrome are not present. Other accident situations can cause carpal tunnel syndrome with a prerequisite being sufficient magnitude of force applied directly to the wrist.
A DNS Study on Roughness-Induced Transition in Oscillating Pipe Flow by Employing Overset Methodology
Authors: Abdulrasool Ali A. , Lee Yongho 
Published: January 2020

Abstract
In this paper, we model a circular pipe with wavy inner wall, for the purpose of studying the role of surface roughness in a purely oscillating flow. Overset-grid technique is utilized for two combined flow domains, and the interpolation process within the shared zone is validated with the exact laminar flow solution for long-time oscillation. Direct numerical simulations are performed at different flow conditions, taking advantage of the overlapping capability of the spectral element method. All simulations begin with zero initial conditions, and periodic boundary conditions are applied at the two ends of the pipe with different roughness heights. The internal pipe roughness modeled by the overset meshes operates as a triggering mechanism for transition to turbulence, and the critical Reynolds number based on the Stokes thickness and the centerline velocity amplitude is determined to be 223.5 at the Stokes number of 10. The results confirm that the periodic turbulence bursts react to the presence of the roughness with different levels of turbulence intensity among the four Stokes numbers presented herein. Additionally, friction losses are calculated and compared with three cases of the existing experimental results for smooth and rough walls.
Effects of dynamic change in fetuin-A levels from the first to the second trimester on insulin resistance and gestational diabetes mellitus: a nested case–control study
Authors: Jin Chuyao , Lin Lizi , Han Na , Zhao Zhiling , Liu Zheng , Luo Shusheng , Xu Xiangrong , Liu Jue , Wang Haijun 
Published: January 2020

ObjectiveTo examine the effects of dynamic change in fetuin-A levels before the diagnosis of gestational diabetes mellitus (GDM) on insulin resistance and GDM.Research design and methodsA total of 135 women with GDM and 135 normal glucose tolerance (NGT) women with matched age (±2 years old) and gestational age at taking the oral glucose tolerance test (OGTT) were included in this nested case–control study. Fasting venous blood samples were collected at the prenatal visit of the first trimester and during OGTT of the second trimester. Plasma concentration of fetuin-A and insulin was determined.ResultsThe plasma fetuin-A concentration in women with GDM was significantly higher than NGT controls in both the first trimester (medians: 403.0 pg/mL vs 273.4 pg/mL; p<0.05) and the second trimester (medians: 475.7 pg/mL vs 290.8 pg/mL; p<0.05) and notably increased from the first to the second trimester. Multivariate linear regression analysis showed that the change in fetuin-A concentration was associated with the changes in fasting insulin, homeostasis model assessment (HOMA) of insulin resistance, and HOMA of β-cell function (HOMA-β) (p<0.05). The highest quartile of the increase in fetuin-A concentration from the first to the second trimester was associated with a higher risk of developing GDM compared with the lowest quartile (OR 2.14; 95% CI 1.05 to 4.37).ConclusionsThe dynamic change in fetuin-A levels was associated with the changes in insulin resistance and β-cell function from the first to the second trimester, and was associated with an increased risk of the development of GDM, indicating that fetuin-A could be a biomarker to predict the risk of GDM.Trial registration numberNCT03814395.
Multistate programme to reduce catheter-associated infections in intensive care units with elevated infection rates
Authors: Meddings Jennifer , Greene M Todd , Ratz David , Ameling Jessica , Fowler Karen E , Rolle Andrew J , Hung Louella , Collier Sue , Saint Sanjay 
Published: January 2020

BackgroundPreventing central line-associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI) remains challenging in intensive care units (ICUs).ObjectiveThe Agency for Healthcare Research and Quality Safety Program for ICUs aimed to reduce CLABSI and CAUTI in units with elevated rates.MethodsInvited hospitals had at least one adult ICU with elevated CLABSI or CAUTI rates, defined by a positive cumulative attributable difference metric (CAD >0) in the Centers for Disease Control and Prevention’s Targeted Assessment for Prevention strategy. This externally facilitated programme implemented by a national project team and state hospital associations included on-demand video modules and live webinars reviewing a two-tiered approach for implementing key technical and socioadaptive factors to prevent catheter infections, using principles and tools based on the Comprehensive Unit-based Safety Program. CLABSI, CAUTI and catheter use data were collected (preintervention 13 months, intervention 12 months). Multilevel negative binomial models assessed changes in catheter-associated infection rates and catheter use.ResultsOf 366 recruited ICUs from 220 hospitals in 16 states and Puerto Rico for two cohorts, 280 ICUs completed the programme including infection outcome reporting; 274 ICUs had complete outcome data for analyses. Statistically significant reductions in adjusted infection rates were not observed (CLABSI incidence rate ratio (IRR)=0.75, 95% CI 0.52 to 1.08, p=0.13; CAUTI IRR=0.79, 95% CI 0.59 to 1.06, p=0.12). Adjusted central line utilisation (IRR=0.97, 95% CI 0.93 to 1.00, p=0.09) and adjusted urinary catheter utilisation were unchanged (IRR=0.98, 95% CI 0.95 to 1.01, p=0.14).ConclusionThis multistate programme targeted ICUs with elevated catheter infection rates, but yielded no statistically significant reduction in CLABSI, CAUTI or catheter utilisation in the first two of six planned cohorts. Improvements in the interventions based on lessons learnt from these initial cohorts are being applied to subsequent cohorts.
Cardiac arrest and sudden cardiac death registries: a systematic review of global coverage
Authors: Paratz Elizabeth Davida , Rowsell Luke , Zentner Dominica , Parsons Sarah , Morgan Natalie , Thompson Tina , James Paul , Pflaumer Andreas , Semsarian Christopher , Smith Karen , Stub Dion , La Gerche Andre 
Published: January 2020

BackgroundSudden cardiac death (SCD) is a major global health problem, accounting for up to 20% of deaths in Western societies. Clinical quality registries have been shown in a range of disease conditions to improve clinical management, reduce variation in care and improve outcomes.AimTo identify existing cardiac arrest (CA) and SCD registries, characterising global coverage and methods of data capture and validation.MethodsBiomedical and public search engines were searched with the terms ‘registry cardio*’; ‘sudden cardiac death registry’ and ‘cardiac arrest registry’. Registries were categorised as either CA, SCD registries or ‘other’ according to prespecified criteria. SCD registry coordinators were contacted for contemporaneous data regarding registry details.ResultsOur search strategy identified 49 CA registries, 15 SCD registries and 9 other registries (ie, epistries). Population coverage of contemporary CA and SCD registries is highly variable with registries densely concentrated in North America and Western Europe. Existing SCD registries (n=15) cover a variety of age ranges and subpopulations, with some enrolling surviving patients (n=8) and family members (n=5). Genetic data are collected by nine registries, with the majority of these (n=7) offering indefinite storage in a biorepository.ConclusionsMany CA registries exist globally, although with inequitable population coverage. Comprehensive multisource surveillance SCD registries are fewer in number and more challenging to design and maintain. Challenges identified include maximising case identification and case verification.Trial registration numberCRD42019118910.
Development of a General Fabrication Strategy for Carbonaceous Noble Metal Nanocomposites with Photothermal Property
Authors: Zhu Hongmei , Jiang Xuchuan 
Published: January 2020

AbstractThis study demonstrates a simple hydrothermal method while can be generalized for controllable synthesis of noble metallic carbonaceous nanostructures (e.g., Au@C, Ag@C) under mild conditions (180–200 °C), which also provides a unique approach for fabricating hollow carbonaceous structures by removal of cores (e.g., silver) via a redox etching process. The microstructure and composition of the as-achieved nanoparticles have been characterized using various microscopic and spectroscopic techniques. Cetyltrimethylammonium bromide (CTAB), serving as a surfactant in the reaction system, plays a key role in the formation of Ag@C, Au@C nanocables, and their corresponding hollow carbonaceous nanotubes in this work. The dynamic growth and formation mechanism of carbonaceous nanostructures was discussed in detail. And finally, laser-induced photothermal property of Au@C nanocomposites was examined. The results may be useful for designing and constructing carbonaceous metal(s) or metal oxide(s) nanostructures with potential applications in the areas of electrochemical catalysis, energy storage, adsorbents, and biomedicine.
Graphic abstract