bluuebunny/crossref_metadata_2025_split huggingface dataset:
The central blood volume as measured by thoracic electrical impedance and plasma proANP is not compromised by donation of 900 mL of blood in men
Authors: Gybel‐Brask Mikkel , Nordsborg Nikolai Baastrup , Goetze Jens P. , Johansson Pär I. , Secher Niels H. , Bejder Jacob 
Published: October 2020

AbstractObjectivesTo evaluate whether the donation of 900 mL of blood reduces the central blood volume (CBV) assessed by thoracic electrical impedance (TI) and plasma pro‐atrial natriuretic peptide (proANP).BackgroundDonation of 450 mL of blood carries a 1% risk of a vasovagal reaction. Withdrawal of 900 mL of blood decreases cardiac output; however, the effect on CBV remains unknown.Methods/MaterialsA randomised, single‐blinded, placebo‐controlled, crossover design was used, where 21 healthy semi‐recumbent men donated 2 × 450 mL blood or were sham‐phlebotomised. Changes in CBV were estimated by proANP and TI at 1.5 (TI1.5) and 100 (TI100) kHz, reflecting extracellular volume and (regional) total body water, respectively, and the index value (IDX; 1/T1.5‐1/TI100) was used to estimate changes in intracellular (red cell) volume. Systolic, diastolic and mean arterial blood pressure; heart rate; stroke volume; cardiac output; and systemic vascular resistance were monitored. After completion of the study, 1000 mL of isotonic saline was infused.ResultsChanges (mean% ± SD) in TI1.5, TI100 and IDX were similar after 450 mL (−0.2 ± 1.6%, 0.0 ± 1.1%, −0.4 ± 10.1%) and 900 mL (0.1 ± 1.6%, 0.2 ± 1.5% and −2.0 ± 15.8%) of blood donation compared to after a sham donation of 450 mL (−0.9 ± 1.2%, −0.5 ± 1.5% and −0.1 ± 6.1%) and 900 mL (−1.2 ± 1.5%, −0.6 ± 1.3% and 0.5 ± 9.9%). In addition, changes in plasma proANP were similar after 450 and 900 mL of blood donation (−0.8 ± 6.7% and −7.6 ± 7.9%) as after sham donations (1.3 ± 7.3% and −4.5 ± 5.6%). Monitoring haemodynamic variables revealed that stroke volume decreased after the donation of 900 mL of blood (−12 ± 12 mL) compared to sham donations.ConclusionDuring a 900‐mL blood loss in semi‐recumbent men, CBV measured by TI and plasma proANP is not affected.
Transition from room temperature to cold‐stored platelets for the preservation of blood inventories during the COVID‐19 pandemic
Authors: Warner Matthew A. , Kurian Emil B. , Hammel Scott A. , van Buskirk Camille M. , Kor Daryl J. , Stubbs James R. 
Published: October 2020

AbstractBackgroundThe COVID‐19 pandemic has placed great strain on blood resources. In an effort to extend platelet (PLT) shelf life and minimize waste, our institution transitioned room temperature to cold‐stored PLTs for administration to bleeding patients.Study Design and MethodsWe describe the administrative and technical processes involved in transitioning room temperature PLTs to cold storage in April 2020. Additionally, we describe the clinical utilization of cold‐stored PLTs in the first month of this practice change, with a focus on changes in PLT counts after transfusion, hemostasis, and safety outcomes.ResultsA total of 61 cold‐stored PLT units were transfused to 40 bleeding patients, with a median (interquartile range [IQR]) of 1 (1‐2) units per patient. The median age was 68 (59‐73) years; 58% male. Median pretransfusion and posttransfusion PLTs counts were 88 (67‐109) and 115 (93‐145). A total of 95% of transfusions were administered in the operating room: 57% cardiac surgery, 20% vascular surgery, 8% general surgery, and 5% solid organ transplantation. Hemostasis was deemed to be adequate in all cases after transfusion. There were no transfusion reactions. One patient (3%) experienced a fever and infection within 5 days of transfusion, which was unrelated to transfusion. Median (IQR) hospital length of stay was 8.5 (6‐17) days. Two patients (5%) died in the hospital of complications not related to transfusion.ConclusionCold‐stored PLT utilization was associated with adequate hemostasis and no overt signal for patient harm. Conversion from room temperature to cold‐stored PLTs may be one method of reducing waste in times of scarce blood inventories.
Aging Mechanisms and Thermal Characteristics of Commercial 18650 Lithium-Ion Battery Induced by Minor Mechanical Deformation
Authors: Li Ling , Chen Xiaoping , Hu Rufu , Wang Tao , Ji Hongbo , Yuan Quan , Ji Yingping , Jiang Zhongqing , Liu Wen , Zheng Weigong 
Published: October 2020

Abstract
Lithium-ion batteries (LIBs) inevitably encounter abusive mechanical loading during engineering applications and result in mechanical deformation, internal short circuit, and even thermal runaway. A 18650 LIB under minor mechanical deformation is subjected to cyclic charge/discharge experiments in this study to analyze its aging behavior. Aging mechanism of the battery with minor deformation is qualitatively investigated through the incremental capacity analysis (ICA). ICA, a commonly used method for exploring degradation mechanism of LIBs, can transform flat voltage plateaus into peaks in the capacity increase curve (IC curve). Experimental data during the battery charging/discharging cycle can be used to calculate the IC curve, which can reflect the characteristics of electrochemical changes inside the battery. Results showed that the LIB suffers from deterioration in the state of health (SOH) in the entire charge/discharge cycle upon minor mechanical deformation. Possible explanations for the slight decrease in SOH with the increasing number of cycles in the early stages and the rapid decrease in the charge/discharge capacity in the late stages were provided. However, precise mechanisms for these phenomena require further detailed research. Moreover, damaged cells demonstrate considerably higher temperature increments than original ones. This temperature difference will increase if additional charging/discharging cycles are conducted. This research infers that additional metallic lithium deposits in damaged cells compared with the original ones cause serious exothermic reactions and lead to enhanced heat accumulation.
Parametric Study on the Safety Behavior of Mechanically Induced Short Circuit for Lithium-Ion Pouch Batteries
Authors: Li Honggang , Zhou Dian , Du Chunlin , Zhang Chao 
Published: October 2020

Abstract
Safety issues of lithium-ion batteries under mechanical abuse have attracted worldwide attention due to its high uncertainty and high risks, following by the rapid increase of market share for lithium-ion battery-driven smart products. In this work, the safety behavior of a pouch battery under mechanical abuse conditions is numerically investigated using a simultaneously coupled mechanical–electrochemical–thermal model. The short-circuit and electrochemical–thermal responses of lithium-ion batteries under various mechanical abuse conditions are successfully predicted and compared. The main impact factors, including the state of charge (SOC), indenter shape and size, and loading displacement, are systematically studied and analyzed. The comprehensive parametric studies show that the battery is in a more dangerous state under higher SOC, identify the critical distinction of the short-circuit behavior between sharp indenter and blunt indenters for battery, and explain the discrepancies in the repeated mechanical abuse tests. These conclusions provide theoretical insights for understanding the failure mechanism of lithium-ion batteries under mechanical abuse, and technical support for the safety design of battery packs.
Effect of Ligament Properties on Nonlinear Dynamics and Wear Prediction of Knee Prostheses
Authors: Askari Ehsan , Andersen Michael S. 
Published: October 2020

Abstract
Although wear is known as the primary cause of long-time failure of total knee arthroplasty (TKA), it can be vital in short- and midterm TKA failure due to laxity. One of the reasons leading to joint laxity and instability is ligamentous insufficiency. This study, therefore, aims to investigate the effects of insufficient ligaments-related knee laxity on both nonlinear dynamics and wear of TKA. The study hypothesizes (a) ligamentous insufficiency can increase TKA damage; (b) stiffness reduction of each of the posterior cruciate ligament (PCL) and medial–lateral collateral ligaments (MCL-LCL) can differently contribute to TKA damage. A forward dynamics methodology is developed and the ligament behavior is simulated employing an asymmetric nonlinear elastic model. External loads and moment, due to the presence of all soft tissues, e.g., muscles and hip joint reaction forces, applied to the femoral bone are determined using a musculoskeletal approach linked to the developed model. A mesh density analysis is performed and comparing outcomes with that available in the literature allows for the assessment of our approach. From the results acquired, reduced PCL stiffness leads to an increase in linear wear rates and results in the maximum damage in TKAs. However, the maximum linear wear rates on both condyles occur once the stiffness of all ligaments is reduced. Moreover, the worn area of the tibia surface increases with the reduction in MCL-LCL stiffness on the medial condyle. The joint with insufficient PCL also shows a considerable increase in ligament forces right after toe-off.
Numerical Analysis of Gas Distribution in 1000 W-Class Solid Oxide Fuel Cell Stack With Internal and External Manifolding
Authors: Blesznowski M. , Boiski M. , Kupecki J. 
Published: October 2020

AbstractSolid oxide fuel cells (SOFC) can generate electricity and heat with a minimal negative impact on the environment and with high electrical efficiency (∼60%). SOFC stacks are the key component of cogeneration units in the range from several kiloWatts up to hundreds of kiloWatts. The larger power output of a system is achieved by the multiplication of a number of separate modules, which are usually based on 1000 W class stacks. In the design of the SOFC stack, the following parts are distinguished: two terminating plates (top and bottom), interconnectors, separators, gaskets, electrical connections, fuel and oxidant delivery lines, and fuel cells. Geometric features and physical and chemical properties of the aforementioned components affect the performance and mechanical strength of the SOFC stack. Two different approaches for air supply can be used and were investigated, namely internal and external manifolding. Comprehensive analysis of the geometric features of the stack together with inserts, the supply and discharge piping of reaction gases, was performed in order to determine the optimal operating conditions on the latest third generation of the SOFC stack, which is currently under development at the Institute of Power Engineering (IEN). This study includes the results of laboratory tests and numerical studies. The results obtained indicate the set of parameters that influence the performance and lifetime of SOFCs. Among others, the most important variables are as follows: fuel type, operating conditions, homogeneity of temperature distribution, and uniformity of gas flow.
Determining Isolated Thumb Forces in Osteoarthritic and Healthy Persons
Authors: Vocelle Amber R. , Shafer Gail , Bush Tamara Reid 
Published: October 2020

Abstract
Carpometacarpal (CMC) osteoarthritis (OA) can dramatically impair thumb function resulting in the inability to complete basic tasks. Development of a method to detect thumb forces changes is essential to understand of the progression of carpometacarpal osteoarthritis and the effects of treatment. The goals of this study were to (1) develop a method to measure thumb forces in multiple directions, (2) perform an initial demonstration of this method on three populations, young healthy (YH), older healthy (OH), and older participants with carpometacarpal osteoarthritis, and (3) determine the effects of short-term exercises on thumb force production in these pilot groups. A multi-axis load cell with a custom-built apparatus and a hand grip dynamometer were used to measure thumb and grip forces. Forces were collected in four directions: radial abduction and adduction, and palmar abduction and adduction. All participants completed thumb and grip testing prior to (week 0), during (week 2), and following (week 6), a hand exercise regimen. Group differences and the effects of exercise on force production were determined. Hand exercises improved thumb forces in young healthy female participants during radial (p = 0.017) and palmar abduction (p = 0.031) and female participants with osteoarthritis during palmar abduction (p = 0.010). Exercise improved grip strength in young healthy males (p = 0.028), young healthy females (p = 0.041), and females with osteoarthritis (p = 0.027). This research demonstrates the successful use of a new device to determine isolated thumb forces, and its clinical utility to identify changes after a short exercise regimen.
Comparison of Poincaré Normal Forms and Floquet Theory for Analysis of Linear Time Periodic Systems
Authors: Subramanian Susheelkumar C. , Redkar Sangram 
Published: October 2020

Abstract
In this work, the authors draw comparisons between the Floquet theory and Normal Forms technique and apply them towards the investigation of stability bounds for linear time periodic systems. Though the Normal Forms technique has been predominantly used for the analysis of nonlinear equations, in this work, the authors utilize it to transform a linear time periodic system to a time-invariant system, similar to the Lyapunov–Floquet (L–F) transformation. The authors employ an intuitive state augmentation technique, modal transformation, and near identity transformations to facilitate the application of time-independent Normal Forms. This method provides a closed form analytical expression for the state transition matrix (STM). Additionally, stability analysis is performed on the transformed system and the comparative results of dynamical characteristics and temporal variations of a simple linear Mathieu equation are also presented in this work.
An In Situ Fabrication of CuGa2 Film on Copper Surface With Improved Tribological Properties
Authors: Li Xing , Yan Chao , Liu Qi , Dong Guangneng 
Published: October 2020

Abstract
Interface interaction between gallium-based liquid metal and copper-based materials results in the formation of intermetallic CuGa2 grains. In particular, CuGa2 grains are able to produce a uniform film and the newly formed CuGa2 film holds peculiar characteristics, which have not been fully explored up to now. In this study, we present an electrochemical fabrication method of an in situ CuGa2 film on copper surface. Surface morphology and chemical composition of this film are confirmed. Tribological experiments demonstrate that the CuGa2 film enables good antifriction and antiwear abilities. Furthermore, the lubrication mechanisms of the CuGa2 film are revealed.
Managing head injury risks in competitive skateboarding: what do we know?
Authors: McIntosh Andrew Stuart , Patton Declan Alexander , McIntosh Alexander GD 
Published: October 2020

ObjectivesThe broad objective of this paper is to inform policy, practice and research regarding the management of head injury risks in competitive skateboarding. The main motivation for the current study was the question of mandating helmet use in competitive skateboarding. The specific aims are to present current knowledge on (A) head injury risks in skateboarding, (B) preliminary biomechanical data on falls and head injury risks in a selection of competitive skateboarding events similar to those planned for the Summer Olympics, (C) standards for skateboard-styled helmets and (D) impact performance of helmets commonly used in skateboarding.MethodsA narrative review of the published literature on head injuries in skateboarding was conducted. Videos of skateboarding competitions from Vans Park Professional League, Street League Skateboarding and Dew Tour were reviewed to describe crashes and falls. Standards databases including the International Organization for Standardization (ISO), British Standards Institution (BSI), Snell, United States Consumer Product Safety Commission (CPSC) and American Society for Testing and Materials (ASTM) were searched for skateboarding-styled helmet standards. A sample of helmets considered suitable for skateboarding was tested in standard impact tests.ResultsThe majority of previous literature focused on the paediatric population in a recreational setting with little data from competitive skateboarding. Head injuries comprised up to 75% of all injuries and helmet use was less than 35%. Video analysis identified high rates of falls and crashes during competitive skateboarding, but also a capacity for the athletes to control falls and limit head impacts. Less than 5% of competitive skateboarders wore helmets. In addition to dedicated national skateboard helmet standards, there are several national standards for skateboard-styled helmets. All helmets, with the exception of one uncertified helmet, had similar impact attenuation performance; that is, at 0.8 m drop height, 114–148 g; at 1.5 m, 173–220 g; and at 2.0 m, 219–259 g. Impact performance in the second impact was degraded in all helmets tested.ConclusionHelmets styled for skateboarding are available ‘off the shelf’ that will offer protection to the head against skull fractures and intracranial injuries in competitive skateboarding. There is an urgent need to commence a programme of research and development to understanding and control head injury risks.
Effect of exercise training for five years on all cause mortality in older adults—the Generation 100 study: randomised controlled trial
Authors: Stensvold Dorthe , Viken Hallgeir , Steinshamn Sigurd L , Dalen Håvard , Støylen Asbjørn , Loennechen Jan P , Reitlo Line S , Zisko Nina , Bækkerud Fredrik H , Tari Atefe R , Sandbakk Silvana B , Carlsen Trude , Ingebrigtsen Jan E , Lydersen Stian , Mattsson Erney , Anderssen Sigmund A , Fiatarone Singh Maria A , Coombes Jeff S , Skogvoll Eirik , Vatten Lars J , Helbostad Jorunn L , Rognmo Øivind , Wisløff Ulrik 
Published: October 2020

AbstractObjectiveTo evaluate the effect of five years of supervised exercise training compared with recommendations for physical activity on mortality in older adults (70-77 years).DesignRandomised controlled trial.SettingGeneral population of older adults in Trondheim, Norway.Participants1567 of 6966 individuals born between 1936 and 1942.InterventionParticipants were randomised to two sessions weekly of high intensity interval training at about 90% of peak heart rate (HIIT, n=400), moderate intensity continuous training at about 70% of peak heart rate (MICT, n=387), or to follow the national guidelines for physical activity (n=780; control group); all for five years.Main outcome measureAll cause mortality. An exploratory hypothesis was that HIIT lowers mortality more than MICT.ResultsMean age of the 1567 participants (790 women) was 72.8 (SD 2.1) years. Overall, 87.5% of participants reported to have overall good health, with 80% reporting medium or high physical activity levels at baseline. All cause mortality did not differ between the control group and combined MICT and HIIT group. When MICT and HIIT were analysed separately, with the control group as reference (observed mortality of 4.7%), an absolute risk reduction of 1.7 percentage points was observed after HIIT (hazard ratio 0.63, 95% confidence interval 0.33 to 1.20) and an absolute increased risk of 1.2 percentage points after MICT (1.24, 0.73 to 2.10). When HIIT was compared with MICT as reference group an absolute risk reduction of 2.9 percentage points was observed (0.51, 0.25 to 1.02) for all cause mortality. Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups.ConclusionThis study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT.Trial registrationClinicalTrials.govNCT01666340.
Eccentric cycling ergometer to address skeletal muscle dysfunction in hospitalised patients: ergometer design, construction and demonstration
Authors: Doyle Mathew , Brown Marc , Kemp Lucy , McLennan Peter , Peoples Gregory 
Published: October 2020

Purpose
Continuous eccentric cycling has demonstrated metabolic efficiency when compared with equivalent concentric workloads. The profile of continuous eccentric cycling is well suited to hospitalised patients, however, its application has been restricted to outpatient settings as ergometers appropriate for the acute setting are currently unavailable. The aim of this study was to construct an eccentric cycle ergometer specifically for use in an acute care hospital ward and demonstrate its performance in healthy subjects.

Methods
An eccentric cycle ergometer (asynchronous 125 W motor) was constructed with strain gauge technology (SRM PowerMetre) to allow instantaneous biofeedback to the user. Ten healthy participants (20–64 years) were used to test the capacity of the ergometer to maintain consistent force production (repeated 5 min duration) with appropriate physiology responses (heart rate, minute ventilation, arterial saturation, electromyography and muscle tissue oxygen saturation) for low to moderate eccentric workloads.

Results

Eccentric power output was consistently achieved without mechanical or ergonomic issues for two workloads (31.1±5.7 W and 56.6±8.8 W, respectively). Participant heart rate (rest: 68±13 bpm) and minute ventilation (rest: 12.4±3.5 L/min) increased incrementally with workload 1 (HR: 83±16 bpm V
E
: 21.76±6.5 L.min-1, p<0.001 vs rest) and workload 2 (HR: 94±14 bpm V
E
: 26.5±8.9 L/min, p<0.001 vs rest) while local muscle oxygen saturation remained unchanged for both workloads.

Conclusion
This study describes the successful construction of an eccentric cycle ergometer and demonstrated the efficacy of the ergometer to deliver constant eccentric workloads in healthy adults. Eccentric cycling could be potentially provided to hospitalised patients using this ergometer.