bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microstructure and Wear Behavior of Nano-TiB2p/2024Al Matrix Composites Fabricated by Laser Direct Energy Deposition With Powder Feeding
Authors: Wang Q. Z. , Lin X. , Wen X. L. , Kang N. , Huang W. D. 
Published: September 2020

Abstract
The purpose of this study is to investigate the effect of TiB2 content on the microstructure and wear behavior of nano-TiB2p/2024Al composites fabricated by laser direct energy deposition (L-DED). The dry sliding friction and wear behavior was evaluated using a ball-on-disk tribometer by sliding samples against a 6-mm diameter GCr15 (AISI52100) steel ball under applied loads of 2.2 N at room temperature. Microstructural characterization of the as-deposited 2024Al alloy showed the presence of oriented columnar grains. Once 3 wt% TiB2 particles were introduced, the as-deposited microstructure consisted of a mixture of columnar and equiaxed grains. It was found that the addition of TiB2 particles can significantly improve the wear resistance of L-DEDed 2024Al. For instance, the wear-rate of an 8 wt% TiB2p/2024Al matrix composite with full equiaxed grains is almost 20 times lower than that of the unreinforced alloy. A grain morphology-induced wear mechanism for the L-DEDed TiB2p/2024Al composites is proposed and is dominated by mutual oxidation and abrasive wear. The research results are beneficial to understand the wear mechanism of L-DEDed nano-TiB2p/2024Al matrix composites and can also provide theoretical guidance for the selection of TiB2 content.
The Application of the Modified Sage-Husa Adaptive Kalman Filter in the Excitation Force Identification of Under-Chassis Active Equipment for Railway Vehicles
Authors: Chen Jiangxue , Zhou Jinsong , Gong Dao , Sun Wenjing , Sun Yu , You Taiwen , Ji Yuanjin 
Published: September 2020

Abstract
Excitation force of under-chassis active equipment of railway vehicles has a significant impact on the floor vibration of the car body. In order to improve the accuracy of the excitation force identification of active equipment in engineering practice, a new excitation force identification method was proposed by applying modified Sage-Husa adaptive Kalman filter (MSHAKF). First, the advantages of the MSHAKF over conventional Kalman filter (CKF) are introduced. Simulation shows that the MSHAKF has excellent exactness and robustness for active equipment excitation force identification. Finally, a test device for identifying excitation force was established. The infinite impulse response (IIR) low-pass filter is designed by using the bilinear transformation method to eliminate the identification error caused by the frequency multiplication components in the response signal. The experimental result shows that the proposed method is very effective in engineering practice without mastering the noise characteristics of the system.
A Novel Accelerometer Mounting Method for Sensing Performance Improvement in Acoustic Measurements From the Knee
Authors: Ozmen Goktug C. , Safaei Mohsen , Lan Lan , Inan Omer T. 
Published: September 2020

AbstractIn this study, we propose a new mounting method to improve accelerometer sensing performance in the 50 Hz–10 kHz frequency band for knee sound measurement. The proposed method includes a thin double-sided adhesive tape for mounting and a 3D-printed custom-designed backing prototype. In our mechanical setup with an electrodynamic shaker, the measurements showed a 13 dB increase in the accelerometer's sensing performance in the 1–10 kHz frequency band when it is mounted with the craft tape under 2 N backing force applied through low-friction tape. As a proof-of-concept study, knee sounds of healthy subjects (n = 10) were recorded. When the backing force was applied, we observed statistically significant (p &lt; 0.01) incremental changes in spectral centroid, spectral roll-off frequencies, and high-frequency (1–10 kHz) root-mean-square (RMS) acceleration, while low-frequency (50 Hz–1 kHz) RMS acceleration remained unchanged. The mean spectral centroid and spectral roll-off frequencies increased from 0.8 kHz and 4.15 kHz to 1.35 kHz and 5.9 kHz, respectively. The mean high-frequency acceleration increased from 0.45 mgRMS to 0.9 mgRMS with backing. We showed that the backing force improves the sensing performance of the accelerometer when mounted with the craft tape and the proposed backing prototype. This new method has the potential to be implemented in today's wearable systems to improve the sensing performance of accelerometers in knee sound measurements.
A Novel Type of Bi-Gyroscopic System Undergoing Both Rotating and Spinning Motions
Authors: Yang Ji-Hou , Yang Xiao-Dong , Qian Ying-Jing , Zhang Wei 
Published: September 2020

Abstract
In order to explore the influence of combined gyroscopic coupling effect on the gyroscopic system, the dynamics of a beam undergoing both rotating and spinning motions as a bi-gyroscopic system is studied. The natural frequencies, modes, and stability of such a bi-gyroscopic system have been studied by the standard eigenvalue problems. The bifurcation series of frequencies and corresponding modal motions have been presented to show the gyroscopically coupled motions. The complex modes of the proposed bi-gyroscopic systems, such as whirling motions and in-plane reeling motions, have been illustrated.
Nonlinear Coupled Torsion/Lateral Vibration and Sommerfeld Behavior in a Double U-Joint Driveshaft
Authors: Yao Wei , DeSmidt Hans 
Published: September 2020

Abstract
Many driveline systems are designed to accommodate angular misalignment by the use of flexible couplings or Universal Joints (U-Joints) which link individual shaft segments. The Sommerfeld effect is a nonlinear phenomenon observed in some rotor systems being driven through a critical speed when there is not enough power to accelerate the rotor through resonance. Previous studies have shown that rotor speed can become captured when transitioning through natural frequencies due to nonlinear interactions between a non-ideal driving input and rotor imbalance. This paper, for the first time, shows that this type of rotor speed capture phenomena can also be induced by driveline misalignment. During rotor spinup under constant motor torque, it is found that misalignment-induced rotor speed capture phenomena can occur as the shaft speed approaches ½ the first elastic torsional natural frequency. Depending on misalignment level and motor torque, the shaft speed will either dwell near this speed and then pass through, or the speed will become trapped. Here, a nonlinear rotordynamics model of a segmented driveshaft connected by two U-joints including effects of angular misalignment and load torque is developed for the study. This analysis also determines the minimum driveline misalignment angle for which the shaft speed capture phenomena will occur for a given motor torque and load torque condition.
Response of Blood Biomarkers to Sprint Interval Swimming
Authors: Kabasakalis Athanasios , Nikolaidis Stefanos , Tsalis George , Mougios Vassilis 
Published: September 2020

Purpose: To evaluate and compare the effects of 2 sprint interval training (SIT) sets of different distances on biochemical markers indicative of metabolism, stress, and antioxidant capacity in competitive swimmers and, to investigate the potential influence of gender on these markers. Methods: Twenty-four adolescent, well-trained swimmers (12 men and 12 women) participated in the study. In a random and counterbalanced order, the swimmers completed 2 SIT sets (8 × 50 m and 8 × 25 m) in freestyle with maximal intensity on different days. Work-to-rest ratio was 1:1 in both sets. Blood samples were drawn preexercise, immediately postexercise, and 1 hour postexercise to evaluate the effects of the SIT sets on a number of biochemical parameters. Results: Swimming speed was higher at 8 × 25 m. The 2 SIT sets induced significant increases in lactate, glucose, insulin, glucagon, cortisol, and uric acid (P ≤ .001). No differences in these parameters were found between sets, except for irisin (higher in 8 × 50 m; P = .02). Male swimmers were faster and had higher lactate and uric acid concentrations, as well as lower reduced glutathione concentration, than female swimmers (P < .01). Conclusions: The 2 swimming SIT sets induced increases in most of the biochemical markers studied. The 2-fold difference between sets in distance did not differentiate the effects of sprint interval exercise on most biochemical parameters. Thus, low-volume SIT sets seem to be effective stimuli for competitive swimmers.
Long-term efficacy of early infliximab-induced remission for refractory uveoretinitis associated with Behçet’s disease
Authors: Keino Hiroshi , Watanabe Takayo , Nakayama Makiko , Komagata Yoshinori , Fukuoka Kazuhito , Okada Annabelle A 
Published: September 2020

Background
To evaluate long-term efficacy of infliximab (IFX) in refractory uveoretinitis associated with Behçet’s disease (BD) depending on uveoretinitis duration.

Methods
Records of 16 patients with BD (32 eyes) followed for >5 years after starting IFX, were retrospectively reviewed. Long-term efficacy was compared between patients with short duration (≤18 months, n=7) versus long duration (>18 months, n=9) of their uveoretinitis prior to starting IFX.

Results
The median follow-up after starting IFX was 132 months (76–146 months). Mean frequency of attacks and the 1-year Behçet’s Disease Ocular Attack Score 24 decreased significantly over 10 years. Overall, the percentage of eyes with a best-corrected visual acuity (BCVA) ≥1.0 increased from 47% at baseline to 59% at 5 years; the percentage of eyes with a BCVA ≤0.1 was 19% at both baseline and 5 years. The frequency of ocular attacks decreased similarly in both short duration and long duration groups; however, the percentage of eyes with a BCVA ≥1.0 at 5 years was 100% in the short duration group versus 28% in the long duration group. IFX was discontinued in four patients with an excellent response to IFX therapy; all were young male patients in the short duration group with good BCVA bilaterally, and none had inflammatory recurrences over a median follow-up of 56 months off IFX.

Conclusion
Initiation of IFX therapy in patients with BD within 18 months of their uveoretinitis onset was more effective in maintaining good BCVA than after 18 months.
What is the impact of Apps in medical education? A study of CAPSULE, a case-based learning App
Authors: Sadler Jonathan , Wright Juliet , Vincent Timothy , Kurka Thomas , Howlett David 
Published: September 2020

IntroductionMobile applications (Apps) are popular in medical education; yet, the actual benefits for students are yet to be formally researched. Clinical And Professional Studies Unique Learning Environment (CAPSULE) is an App created by Brighton and Sussex Medical School. The App provides 650 cases offered to students in their final two years of the undergraduate programme. The App performed consistently well in student feedback, and therefore, a study into the educational benefits of the App was constructed.MethodsA cross-sectional study was performed following two years of use by students to investigate the relationship between App usage and decile ranking.ResultsThe study found that the students who completed more cases tended to score higher per case (p value=0.0037). The study also found a trend between having higher case scores and being part of a stronger decile (p value=0.019).ConclusionsGreater App usage was linked with performing better in the App itself and this was further associated with being in a stronger decile rank. From a user perspective, the data generated from the App could help with identifying students who are underperforming or help students to recognise areas on which they need to focus.
Comparison of carotid artery ultrasound and Framingham risk score for discriminating coronary artery disease in patients with psoriatic arthritis
Authors: Cheng Isaac T , Wong Ka Tak , Li Edmund K , Wong Priscilla C H , Lai Billy T , Yim Isaac C , Ying Shirley K , Kwok Kitty Y , Li Martin , Li Tena K , Lee Jack J , Lee Alex P , Tam Lai-Shan 
Published: September 2020

ObjectivesThis study aimed to assess the performance of carotid ultrasound (US) parameters alone or in combination with Framingham Risk Score (FRS) in discriminating patients with psoriatic arthritis (PsA) with and without coronary artery disease (CAD).MethodsNinety-one patients with PsA (56 males; age: 50±11 years, disease duration: 9.4±9.2 years) without overt cardiovascular (CV) diseases were recruited. Carotid intima-media thickness (cIMT), the presence of plaque and total plaque area (TPA) was determined by high-resolution US. CAD was defined as the presence of any coronary plaque on coronary CT angiography (CCTA). Obstructive-CAD (O-CAD) was defined as >50% stenosis of the lumen.ResultsThirty-five (38%) patients had carotid plaque. Fifty-four (59%) patients had CAD (CAD+) and 9 (10%) patients had O-CAD (O-CAD+). No significant associations between the presence of carotid plaque and CAD were found. However, cIMT and TPA were higher in both the CAD+ and O-CAD+ group compared with the CAD− or O-CAD− groups, respectively. Multivariate logistic regression analysis revealed that mean cIMT was an independent explanatory variable associated with CAD and O-CAD, while maximum cIMT and TPA were independent explanatory variables associated with O-CAD after adjusting for covariates. The optimal cut-offs for detecting the presence of CAD were FRS >5% and mean cIMT at 0.62 mm (AUC: 0.71; sensitivity: 67%; specificity: 76%), while the optimal cut-offs for detecting the presence of O-CAD were FRS >10% in combination with mean cIMT at 0.73 mm (AUC: 0.71; sensitivity: 56%; specificity: 85%).ConclusionUS parameters including cIMT and TPA may be considered in addition to FRS for CV risk stratification in patients with PsA.
Staged angioplasty versus regular carotid artery stenting in patients with carotid artery stenosis at high risk of hyperperfusion: a randomised clinical trial
Authors: Mo Dapeng , Jia Baixue , Shi Huaizhang , Sun Yaxuan , Liu Qingan , Fan Chengzhe , Deng Jianping , Yuan Jinglin , Wu Wei , Jiang Changchun , Zhang Guilian , Du Hanjun , Ma Ning , Gao Feng , Sun Xuan , Song Ligang , Liu Lian , Peng Guangge , Wang Yongjun , Wang Yilong , Miao Zhongrong 
Published: September 2020

Background and purposeHyperperfusion (HP) is a devastating complication associated with carotid artery stenting (CAS) or endarterectomy. The efficacy and safety of staged angioplasty (SAP) in patients with CAS at high risk of HP remains unclear. We sought to determine whether SAP is superior to regular CAS in patients with high risk of HP.MethodsA randomised, multicentre open-label clinical trial with blinded outcome assessment (STEP) was conducted. Patients with severe carotid stenosis at high risk of HP were randomly assigned (1:1) to the SAP or regular CAS group. The primary endpoint was hyperperfusion syndrome (HPS) and intracerebral haemorrhage (ICH) within 30 days after the procedure.ResultsFrom November 2014 to January 2017, a total of 64 patients were enrolled in 11 centres. 33 patients were allocated to the SAP group and 31 to the regular CAS group. At 30 days, the rate of primary endpoint was 0.0% (0/33) in the SAP group and 9.7% (3/31) in the regular CAS group (absolute risk reduction (ARR), 9.7%; 95% CI −20.1% to 0.7%; p=0.11). As one of the secondary endpoints, the incidence of HP phenomenon (HPP) was lower in the SAP group than the regular CAS group (0.0% vs 22.6%, ARR,−22.6%; 95% CI −36.8% to −10.2%; p=0.04).ConclusionThe rate of HPS and ICH was not significantly lower in SAP group; the extended secondary endpoint of HPP, however, significantly reduced, which suggested that SAP may be a safe and effective carotid revascularisation procedure to prevent HP.Trial registration numberNCT02224209.
Experimental modelling of seasonal thermal energy storage within unconfined aquifer (ATES)
Authors: Charlwood S.P. , Madabhushi S.P.G. 
Published: September 2020

Aquifer thermal energy storage systems allow the storage of excess heat from summer for use during the winter. This investigation looks at the suitability of a small-scale experimental model as a method for simulating the behaviour of full-scale unconfined aquifers for thermal storage. Thermal energy was stored via the injection of 40, 60, and 80 °C water for a period of 1000 s with extraction being between 1000 and 2000 s. Furthermore, periods of storage between injection and extraction were introduced to simulate potential full-scale heating and cooling demand scenarios. Thermal efficiencies were found to be ∼60% reducing to ∼53% with the addition of a 1000 s storage period. Furthermore, for the model tested in this investigation the temperature of the injected water was found to have little influence upon the efficiency.
Antenatal Dexamethasone Exposure Impairs the High-Conductance Ca
2+
-Activated K
+
Channels via Epigenetic Alteration at Gene Promoter in Male Offspring
Authors: Xu Ting , Zhao Meng , Li Huan , Zhou Xiuwen , Liu Bailin , Sun Miao , Xu Zhice , Gao Qinqin 
Published: September 2020

Objective:

Antenatal exposure to glucocorticoids increases cardiovascular risks related to vascular dysfunctions in offspring, although underlying mechanisms are still unknown. As an important vascular mediator, high-conductance Ca
2+
-activated K
+
channels (BK) plays an essential role in determining vascular tone. Long-term effects of antenatal glucocorticoids on BK in offspring are largely unknown. This study examined the effects and mechanisms of antenatal exposure to clinically relevant doses of glucocorticoids on vascular BK in offspring.

Approach and Results:

Pregnant Sprague-Dawley rats received synthetic glucocorticoids dexamethasone or vehicle during the last week of pregnancy. Vascular functions, cellular electrophysiology, target gene expression, and promoter methylation were examined in mesenteric arteries of male offspring (gestational day 21 [fetus] and postnatal day 120 [adult offspring]). Antenatal dexamethasone exposure impaired BK activators-mediated relaxation and reduced whole-cell BK currents in mesenteric arteries. Antenatal dexamethasone exposure did not alter Ca
2+
/voltage-sensitivity of BK but downregulated the expressions of BK α and β1 subunits in both fetal and adult mesenteric arteries. In addition, increased promoter methylations within
BKα
and
BKβ1
were compatible with reduced expressions of the 2 genes.

Conclusions:
Our findings showed a profound and long-term impact of antenatal dexamethasone exposure on vascular BK via an altered epigenetic pattern from fetal stage to adulthood, advancing understanding of prolonged adverse effects and mechanisms of antenatal glucocorticoids exposure on vascular health in offspring.
A Model of the Fed's View on Inflation
Authors: Hasenzagl Thomas , Pellegrino Filippo , Reichlin Lucrezia , Ricco Giovanni 
Published: September 2020

AbstractWe develop a medium-size semistructural time series model of inflation dynamics that is consistent with the view, often expressed by central banks, that three components are important: a trend anchored by long-run expectations, a Phillips curve, and temporary fluctuations in energy prices. We find that a stable long-term inflation trend and a well-identified steep Phillips curve are consistent with the data, but they imply potential output declining since the new millennium and energy prices affecting headline inflation not only via the Phillips curve but also via an independent expectational channel.
Fear and Loathing in the Anthropocene: Grief, Compassion and the Benefits of Literature
Authors: Harris Stephen 
Published: September 2020

Abstract
This essay considers the nexus between literature and compassion in relation to the well-reported global environmental crisis and the attendant range of emotions, as signalled by the terms ‘ecocide’, ‘extinction crisis’ and ‘eco-anxiety’. While the words ‘grief’ and ‘hope’ have come to represent a range of associated emotions and feelings, there are important affective inflections occurring between these two semantic reference points, which are in themselves significant, if less amenable to debate and conversion to meaningful action. The following essay considers the nuances of these same affective extremities and emotional complexities, with particular reference to collective emotions such as anger and fear, and the implications of sustained feelings of dread, despair and collective trauma. The essay concludes by arguing for the constructive role of literature in mediating collective feeling and redirecting negative public emotions.
Slow-wave sleep is associated with incident hypertension in patients with obstructive sleep apnea: a cross-sectional study
Authors: Zhang Jing , Zhuang Yan , Wan Nan-sheng , Tang Xin , Zhou Wei , Si Liang , Wang Yan , Chen Bao-yuan , Cao Jie 
Published: September 2020

Objective This study aimed to examine the association between slow-wave sleep ([SWS] N3 stage) and the risk of hypertension in patients with obstructive sleep apnea (OSA) or primary snorers. Methods A retrospective cross-sectional study of 1145 participants who were evaluated for suspected OSA at our Sleep Medical Center were included. Among these participants, 1022 had OSA and 123 were primary snorers. Logistic regression modeling was performed to evaluate the association between the prevalence of hypertension and combined OSA and SWS based on polysomnographic measurements. Results Patients with OSA in the lowest SWS quartile (quartile 1,  < 2.0%) showed a two-fold increased risk of hypertension after adjustment for confounding factors compared with primary snorers (odds ratio, 2.13 [95% confidence interval 1.54–2.06]). In logistic analysis stratified according to SWS quartiles, there was no significant difference in the risk of hypertension between patients with OSA and primary snorers in quartile 1. However, in the highest quartile (quartile 4), SWS was significantly associated with incident hypertension in patients with OSA rather than primary snorers. Conclusion SWS is associated with prevalent hypertension in patients with OSA. Notably, a low proportion of SWS confers a stronger association with incident hypertension than OSA.
Association between incubation period and clinical characteristics of patients with COVID-19
Authors: Cai Yeyu , Liu Jiayi , Yang Haitao , Wang Mian , Guo Qingping , Huang Deng , Yu Qizhi , Xiao Enhua 
Published: September 2020

Purpose To investigate associations between the clinical characteristics and incubation periods of patients infected with coronavirus disease 2019 (COVID-19) in Wuhan, China. Methods Complete clinical and epidemiological data from 149 patients with COVID-19 at a hospital in Hunan Province, China, were collected and retrospectively analyzed. Results Analysis of the distribution and receiver operator characteristic curve of incubation periods showed that 7 days was the optimal cut-off value to assess differences in disease severity between groups. Patients with shorter (≤7 days) incubation periods (n = 79) had more severe disease, longer durations of hospitalization, longer times from symptom onset to discharge, more abnormal laboratory findings, and more severe radiological findings than patients with longer (>7 days) incubation periods. Regression and correlation analyses also showed that a shorter incubation period was associated with longer times from symptom onset to discharge. Conclusion The associations between the incubation periods and clinical characteristics of COVID-19 patients suggest that the incubation period may be a useful marker of disease severity and prognosis.