bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduced field‐of‐view diffusion‐weighted MRI can identify restricted diffusion in the spinal cord of dogs and cats with presumptive clinical and high‐field MRI diagnosis of acute ischemic myelopathy
Authors: Mai Wilfried 
Published: November 2020

AbstractDiffusion‐weighted imaging MRI is the gold standard imaging technique for diagnosis of suspected acute brain ischemia in dogs and cats; however, it is technically challenging to apply to spinal cord imaging, due to its very small size, the inherent low spatial resolution of diffusion‐weighted imaging, and the marked distortion resulting from magnetic field inhomogeneities caused by the osseous components of the vertebral column surrounding the spinal cord. Ischemic myelopathy is a common cause of acute non‐compressive myelopathy in dogs and cats. Technological improvement in diffusion‐weighted imaging pulse sequences allow imaging at smaller field of view with better spatial resolution and less image distortion. We sought to evaluate reduced field‐of‐view diffusion‐weighted imaging MRI using a dedicated proprietary pulse sequence (FOCUS, General Electric) in a small sample of dogs and cats with a presumptive clinical and MRI diagnosis of acute ischemic myelopathy that were imaged with this pulse sequence. Five dogs and two cats fitted these inclusion criteria. In all of them, hyperintense spinal cord parenchyma signal was seen on diffusion‐weighted imaging images corresponding to decreased signal on apparent diffusion coefficient map indicative of restricted diffusion, consistent with ischemia and cytotoxic edema. These areas matched the areas of abnormal T2‐weighted signal and cord swelling observed on conventional spinal MRI. This small exploratory descriptive study indicates feasibility and possible usefulness of reduced field‐of‐view diffusion‐weighted imaging MRI in dogs and cats with suspected acute ischemic myelopathy and that it may be added to the imaging protocol of the spine in such patients in an appropriate clinical setting.
Indomethacin markedly blunts cerebral perfusion and reactivity, with little cognitive consequence in healthy young and older adults
Authors: Shoemaker L. N. , Wilson L. C. , Lucas S. J. E. , Machado L. , Walker R. J. , Cotter J. D. 
Published: November 2020

Key points
Cognitive function depends on adequate cerebrovascular perfusion and control. However, it is unknown whether acutely‐reduced cerebral blood flow (CBF) impairs cognition in healthy adults.
In the present study, we used a placebo‐controlled, single‐blinded, randomized cross‐over design to test the hypothesis that acutely‐reduced CBF (using a pharmacological aid; indomethacin) would impair cognition in young and older healthy adults.
At baseline, older adults had lower cognitive performance and CBF, but similar cerebrovascular reactivity to CO2 and dynamic cerebral autoregulation compared to young adults.
In both young and older adults, cognitive performance on a mental switching task was slightly (7%) reduced after indomethacin, but not significantly associated with reductions in CBF (∼31%).
These results indicate that cognitive performance is broadly resilient against a ∼31% reduction in CBF per se in healthy young and older adults.
AbstractCognitive function depends on adequate cerebrovascular perfusion and control. However, it is unknown whether acutely‐reduced cerebral blood flow (CBF) impairs cognition in healthy adults. Using a placebo‐controlled, single‐blinded, randomized cross‐over design, we tested the hypothesis that acutely‐reduced CBF (using indomethacin [1.2 mg kg–1 oral dose]) would impair cognition in young (n = 13; 25 ± 4 years) and older (n = 12; 58 ± 6 years) healthy adults. CBF and cerebrovascular control were measured using middle cerebral artery blood velocity (MCAvmean) and its reactivity to hypercapnia (CVRHYPER) and hypocapnia (CVRHYPO), respectively. Cognitive function was assessed using a computerized battery including response time tasks. Baseline comparisons revealed that older adults had 14% lower MCAvmean and 15% lower cognitive performance (all P ≤ 0.048), but not lower CVRHYPER/HYPO (P ≥ 0.26). Linear and rank‐based mixed models revealed that indomethacin decreased MCAvmean by 31% (95% confidence interval = –35 to –26), CVRHYPER by 68% [interquartile range (IQR) = –94 to –44] and CVRHYPO by 50% (IQR = –83 to –33) (treatment‐effect; all P < 0.01), regardless of age. Baseline CVRHYPER/HYPO values were strongly associated with their indomethacin‐induced reductions (r = 0.70 to 0.89, P < 0.01). Mental switching performance was impaired 7% (IQR = 0–19) after indomethacin (P = 0.04), but not significantly associated with reductions in MCAvmean (Young: rho = –0.31, P = 0.30; Older: rho = 0.06, P = 0.86). In conclusion, indomethacin reduced MCAvmean and impaired cognition slightly; however, no clear association was evident in younger or older adults. Older adults had poorer cognition and lower MCAvmean, but similar CVRHYPER/HYPO.
Framing and Tracing Human-Centered Design Teams’ Method Selection: An Examination of Decision-Making Strategies
Authors: Rao Vivek , Kim Euiyoung , Kwon Jieun , Agogino Alice M. , Goucher-Lambert Kosa 
Published: November 2020

AbstractDesigners’ choices of methods are well known to shape project outcomes. However, questions remain about why design teams select particular methods and how teams’ decision-making strategies are influenced by project- and process-based factors. In this mixed-methods study, we analyze novice design teams’ decision-making strategies underlying 297 selections of human-centered design methods over the course of three semester-long project-based engineering design courses. We propose a framework grounded in 100+ factors sourced from new product development literature that classifies design teams’ method selection strategy as either Agent- (A), Outcome- (O), or Process- (P) driven, with eight further subclassifications. Coding method selections with this framework, we uncover three insights about design team method selection. First, we identify fewer outcomes-based selection strategies across all phases and innovation types. Second, we observe a shift in decision-making strategy from user-focused outcomes in earlier phases to product-based outcomes in later phases. Third, we observe that decision-making strategy produces a greater heterogeneity of method selections as compared to the class average as a whole or project type alone. These findings provide a deeper understanding of designers’ method selection behavior and have implications for effective management of design teams, development of automated design support tools to aid design teams, and curation of design method repositories.
Investigation of the Capabilities of Transverse Magnetic Field Controlled Laser-Induced Plasma Micro-Machining
Authors: Zhang Yanming , Liu Yayun , Bhandari Suman , Zhang Guojun , Deng Jianxin , Zhang Zhen , Ehmann Kornel 
Published: November 2020

Abstract
Laser-induced plasma micro-machining (LIPMM) has proven a number of advantages in micro-machining due to reduced thermal defects, smaller heat-affected zones, and larger aspect ratios when compared with conventional laser ablation. The present work explores the use of external magnetic fields to further enhance process outcomes in LIPMM. Specifically, machining characteristics and outcomes including plasma intensity, attainable aspect ratios, and surface quality will be explored through a theoretical and experimental study in different classes of materials in a transverse magnetic field controlled LIPMM. First, process improvement mechanisms are illustrated in terms of plasma confinement and laser absorption in transverse magnetic fields. A magnetic field redistribution analysis is performed to reveal the differences in the achievable enhancements in machining characteristics in terms of material characteristics. Second, a set of single-factor experiments is conducted to investigate the effects of the strength and direction of the magnetic field on machining capabilities in magnetic and nonmagnetic materials (410, 304 stainless steels and silicon). The experimental results show that plasma intensity and aspect ratios can be significantly increased in the presence of transverse magnetic fields. The greatest influence on machining capability is achieved in a magnetic material. In this case, plasma intensity and aspect ratios were increased by about 176% and 160%, respectively, when compared with other materials with a magnetic field strength of 0.1 T and a magnetic field direction parallel to the processing direction. Finally, the morphology and cross-section profiles of micro-channels have been measured for verifying the impact on the surface quality of transverse magnetically controlled LIPMM.
Comparative Study of Incremental Forming and Elevated Temperature Incremental Forming Through Experimental Investigations on AA 1050 Sheet
Authors: Singh Swarit Anand , Priyadarshi Satwik , Tandon Puneet 
Published: November 2020

Abstract
Unlike conventional forming processes, incremental forming (IF) does not require any part-specific tooling. It is a flexible forming process that is suitable to form user-specific shapes and for low volume production. The IF process has been recognized as a promising manufacturing process over conventional forming for the materials having decent formability. However, it does not give reliable results while forming hard to form materials. A few investigations revealed that heat plays a vital role in enhancing the formability. On heating, the yield stress of the materials gets reduced, the ductility increases, and hence the formability improves. Thus, for the materials having poor formability, an advance IF technique, elevated temperature incremental forming (ET-IF), has been developed. ET-IF involves incremental forming of the sheets while being heated by an external heat supply. This research study focuses on the execution of the ET-IF process and its comparison with the conventional IF process. A radiation type heating device to perform the ET-IF process is designed and fabricated. The experimental investigations were carried out on 1 mm thick AA 1050 sheets by carrying out the IF process at room temperature and enhanced temperatures. Experimentation was initiated with performing straight grove tests, which were later extended to form a few more shapes. Experimental results confirm the delay in fracture and intensification of formability with the ET-IF process in comparison to that of the IF process at room temperature. The work overcomes the limitation and enlarges the scope of application of the IF process.
Study of Relative Endwall Motion Effects in a Compressor Cascade Through Direct Numerical Simulations
Authors: Ventosa-Molina Jordi , Lange Martin , Mailach Ronald , Fröhlich Jochen 
Published: November 2020

Abstract
Linear cascades are commonly used as surrogate geometries when performing fundamental studies of turbomachinery blading. Several effects are not accounted for in linear cascades, such as the relative motion between blade and endwall. In this study, three different relative endwall velocities are analyzed. The effect of the relative motion between endwall and blade in a linear compressor cascade is studied through direct numerical simulations. Results show a significant change in the secondary flow structure within the passage. Most notably, the tip leakage vortex is displaced away from the blade. Still, the blade spanwise range affected by the secondary flow field is similar to the case without relative endwall motion. At the outlet plane, a stratification of the total pressure losses and the exit flow angle is found, which overshadows any blade wake effects near the endwall.
Numerical Study on Flow Field in a Peripheral Ported Rotary Engine Under the Action of Apex Seal Leakage
Authors: Fan Baowei , Wang Yuanguang , Pan Jianfeng , Zhang Yaoyuan , Zeng Yonghao 
Published: November 2020

Abstract
Apex seal leakage is one of the main defects restricting the performance improvement of rotary engines. The aim of this study is to study the airflow movement in a peripheral ported rotary engine under the action of apex seal leakage. For this purpose, a three-dimensional (3D) dynamic calculation model considering apex seal leakage was first established and verified by particle image velocimetry data. Furthermore, based on the established 3D model, the flow field in the combustion chamber under the four apex seal leakage gaps (0.02, 0.04, 0.06, and 0.08 mms) and the three engine revolution speeds (2000, 3500, and 5000 RPMs) was calculated. By comparing with the flow field under the condition without leakage, the influences of the existence of apex seal leakage on the velocity field, the turbulent kinetic energy, and the volumetric efficiency in the combustion chamber were investigated. Thereinto, the influences of the existence of apex seal leakage on the velocity field is that at the intake stroke, a vortex formed in the middle of the combustion chamber under the condition without apex seal leakage, was intensified by the apex seal leakage action. At the compression stroke, irrespective of the condition with or without apex seal leakage, all vortexes in the combustion chamber are gradually broken into a unidirectional flow. However, there is an obvious “leakage flow area” at the end of combustion chamber due to the existence of apex seal leakage.
A Detailed Description of Flow-Deck Interaction in Consecutive Green Water Events
Authors: Hernández-Fontes Jassiel V. , Mendoza Edgar , Hernández Irving D. , Silva Rodolfo 
Published: November 2020

Abstract
This paper gives a detailed description of the main hydrodynamic characteristics of different types of green water events occurring on a fixed structure in a series of experiments. High-speed video, at 250 fps, was used to capture the flow details from regular waves produced inside a wave flume. The green water events were classified according to their type and the results of the evaluation from the apparent and effective interaction features. The air cavities in the plunging-dam-break (PDB)-type events were almost spherical for longer waves. PDB with large, elliptical cavities, and hammer-fist (HF)-type events occurred with steeper waves. The highest wave front and bow run-up velocities were found in PDB and HF events, respectively. The size of the cavities in PDB events increases and becomes more elliptical for higher bow run-up velocities. The results of these experiments show that not all events can be treated in the same way as the dam-break (DB)-type events when designing structures or implementing models, as not all interactions with the deck happen when the shipping water crosses the bow edge.
Analysis of Gas Production in Overcharged Lithium Battery by X-Ray Computed Tomography
Authors: Zhang Xiaofan , Li Lifu , Xu Wei 
Published: November 2020

Abstract
Overcharge is one of the main factors that lead to thermal runaway of lithium batteries. However, there is no research on the quantitative relationship between overcharged state and gas production, so as to effectively monitor the safe state of the battery and avoid thermal runaway. In this paper, X-ray computed tomography (CT) is proposed to explore the overcharge battery. The internal structure changes of bulge deformation and electrode separation is observed from tomographic images of two different cross-sectional directions. The relationship between gas production and overcharge state of charge (SOC) is quantitatively analyzed. As overcharge SOC increases, gas production increases exponentially. Gas distribution is analyzed by density distribution feature (DDF) vector. The gas production is mainly distributed in the middle of the overcharge batteries. It is envisaged that these techniques can be used to better understand the overcharge of battery nondestructively, visually and effectively, then will lead to avoid the occurrence of thermal runaway.
Stress-Blended Eddy Simulation/Flamelet Generated Manifold Simulation of Film-Cooled Surface Heat Transfer and Near-Wall Reaction
Authors: Xia Yu , Sharkey Patrick , Orsino Stefano , Kuron Mike , Menter Florian , Verma Ishan , Malecki Robert , Sen Baris 
Published: November 2020

Abstract
Accurate numerical prediction of surface heat transfer in the presence of film cooling within aero-engine sub-components, such as blade effusion holes and combustor liners, has long been a goal of the aero-engine industry. It requires accurate simulation of the turbulent mixing and reaction processes between freestream and the cooling flow. In this study, the stress-blended eddy simulation (SBES) turbulence model is used together with the flamelet generated manifold (FGM) combustion model to calculate the surface heat flux upstream and downstream of an effusion cooling hole. The SBES model employs a blending function to automatically switch between Reynolds-averaged Navier–Stokes (RANS) and large eddy simulation (LES) based on the local flow features, and thus significantly reduces the computational cost compared to a full LES simulation. All simulations are run using ansys fluent®, a commercial finite-volume computational fluid dynamics (CFD) solver. The test case corresponds to an experimental rig run at Massachusetts Institute of Technology (MIT), which is essentially a flat plate brushed by a uniform freestream of argon with ethylene seeded inside, and is cooled by either a reacting air or a non-reacting nitrogen jet inclined at 35 deg to the freestream. Calculations are performed for both reacting and non-reacting jet cooling cases across a range of jet-to-stream blowing ratios and compared with the experimental data. The effects of mesh resolution are also investigated. Calculations are also performed across a range of Damköhler number (i.e., flow to chemical time ratio) from zero to 30, with unity blowing ratio, and the differences in the maximum surface heat flux magnitude in the reacting and non-reacting cases at a specific location downstream of the hole are investigated. Results from these analyses show good correlation with the experimental heat flux data upstream and downstream of the cooling hole, including the heat flux augmentation due to local reaction. Results from the Damköhler number sweep also show a good match with the experimental data across the range investigated.
Effect of Stretching Protocols on Glenohumeral-Joint Muscle Activation in Elite Table Tennis Players
Authors: Kazemi Omid , Letafatkar Amir , Marchetti Paulo H. 
Published: November 2020

Context: Several studies report static-stretch-induced deficits and dynamic-stretch performance improvement after intervention. Purpose: To investigate the muscle activation of the forehand and backhand in table tennis players after experiencing static- and dynamic-stretching protocols. Methods: A total of 24 elite male table tennis players (age 22.7 [3.46] y, height 1.78 [0.03] m) were tested before and 0, 10, 20, and 30 min after the 3 conditions (dynamic stretch, static stretch, and no stretch). The MEGA ME6000 (Mega Electronics, Kuopio, Finland) was used to capture the surface EMG data of the anterior deltoid, middle deltoid, posterior deltoid, biceps, and triceps muscles. Muscle activation data of the pretest were compared with posttest 0, 10, 20, and 30 min. These data were also compared between 3 different conditions (dynamic stretch, static stretch, and no stretch). Results: A 2-way repeated-measures analysis of variance indicated significant differences in the forehand and backhand, and Bonferroni test as a post hoc comparison revealed significant differences between the pretest and posttests in several muscles (P < .05). Furthermore, there were significant differences in the posttest between the 3 conditions (P < .05). Conclusions: In general, there was a short-term effect of static- and dynamic-stretching protocols on glenohumeral-joint muscle activation in elite table tennis players. The static and dynamic stretching presented a decrease and increase, respectively, in muscle activation up to 30 min after stretching. In conclusion, the additive and subtractive effects of dynamic- and static-stretching protocols on muscle activation seem to persist after 30 min.
Clinician and computer: a study on patient perceptions of artificial intelligence in skeletal radiography
Authors: York Thomas , Jenney Heloise , Jones Gareth 
Published: November 2020

BackgroundUp to half of all musculoskeletal injuries are investigated with plain radiographs. However, high rates of image interpretation error mean that novel solutions such as artificial intelligence (AI) are being explored.ObjectivesTo determine patient confidence in clinician-led radiograph interpretation, the perception of AI-assisted interpretation and management, and to identify factors which might influence these views.MethodsA novel questionnaire was distributed to patients attending fracture clinic in a large inner-city teaching hospital. Categorical and Likert scale questions were used to assess participant demographics, daily electronics use, pain score and perceptions towards AI used to assist in interpretation of their radiographs, and guide management.Results216 questionnaires were included (M=126, F=90). Significantly higher confidence in clinician rather than AI-assisted interpretation was observed (clinician=9.20, SD=1.27 vs AI=7.06, SD=2.13), 95.4% reported favouring clinician over AI-performed interpretation in the event of disagreement.Small positive correlations were observed between younger age/educational achievement and confidence in AI-assistance. Students demonstrated similarly increased confidence (8.43, SD 1.80), and were over-represented in the minority who indicated a preference for AI-assessment over their clinicians (50%).ConclusionsParticipant’s held the clinician’s assessment in the highest regard and expressed a clear preference for it over the hypothetical AI assessment. However, robust confidence scores for the role of AI-assistance in interpreting skeletal imaging suggest patients view the technology favourably.Findings indicate that younger, more educated patients are potentially more comfortable with a role for AI-assistance however further research is needed to overcome the small number of responses on which these observations are based.