bluuebunny/crossref_metadata_2025_split huggingface dataset:
Viscoelastic Testing in the Clinical Management of Subarachnoid Hemorrhage and Intracerebral Hemorrhage
Authors: Hvas Christine Lodberg , Hvas Anne-Mette 
Published: September 2022

AbstractSubarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH) are both debilitating and life-threatening incidents calling for immediate action and treatment. This review focuses on the applicability of viscoelastic testing (rotational thromboelastometry or thromboelastography [TEG]) in the management of SAH and ICH. A systematic literature search was performed in PubMed and EMBASE. Studies including patients with SAH or ICH, in which viscoelastic testing was performed, were identified. In total, 24 studies were included for analysis, and further subdivided into studies on SAH patients investigated prior to stenting or coiling (n = 12), ICH patients (n = 8) and studies testing patients undergoing stenting or coiling, or ischemic stroke patients undergoing thrombolysis or thrombectomy and developing ICH as a complication (n = 5). SAH patients had increased clot firmness, and this was associated with a higher degree of early brain injury and higher Hunt-Hess score. SAH patients with delayed cerebral ischemia had higher clot firmness than patients not developing delayed cerebral ischemia. ICH patients showed accelerated clot formation and increased clot firmness in comparison to healthy controls. Patients with hematoma expansion had longer clot initiation and lower platelet aggregation than patients with no hematoma expansion. During stent procedures for SAH, adjustment of antiplatelet therapy according to TEG platelet mapping did not change prevalence of major bleeding, thromboembolic events, or functional outcome. Viscoelastic testing prior to thrombolysis showed conflicting results in predicting ICH as complication. In conclusion, viscoelastic testing suggests hypercoagulation following SAH and ICH. Further investigation of the predictive value of increased clot firmness in SAH seems relevant. In ICH, the prediction of hematoma expansion and ICH as a complication to thrombolysis might be clinically relevant.
Training Tomorrow’s Aquatic Leaders: a Collaborative Model in the Regional District of Nanaimo on Vancouver Island
Authors: Porteous Anne M. 
Published: September 2022

Abstract
The recruitment, training and retention of Lifeguard/Swimming Instructors is essential for the provision of safe and high-quality aquatic programs. For years, recruitment, training and retention has become increasingly challenging. The issue was identified in Ontario, Canada, in 2005, and over the past ten years the issue has continued right across the country. The author, who works as an Aquatic Recreation Programmer for the Regional District of Nanaimo (RDN) on Vancouver Island, BC, has recently been dealing with this mounting problem.

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Vancouver Island University World Leisure Centre of Excellence
© A.M. Porteous, 2015
Forecasting stock options prices via the solution of an ill-posed problem for the Black–Scholes equation
Authors: Klibanov Michael V , Shananin Aleksander A , Golubnichiy Kirill V , Kravchenko Sergey M 
Published: September 2022

Abstract
In the previous paper (2016 Inverse Problems
32 015010), a new heuristic mathematical model was proposed for accurate forecasting of prices of stock options for 1–2 trading days ahead of the present one. This new technique uses the Black–Scholes equation supplied by new intervals for the underlying stock and new initial and boundary conditions for option prices. The Black–Scholes equation was solved in the positive direction of the time variable, this ill-posed initial boundary value problem was solved by the so-called quasi-reversibility method (QRM). This approach with an added trading strategy was tested on the market data for 368 stock options and good forecasting results were demonstrated. In the current paper, we use the geometric Brownian motion to provide an explanation of that effectivity using computationally simulated data for European call options. We also provide a convergence analysis for QRM. The key tool of that analysis is a Carleman estimate.
Simultaneous recoveries for semilinear parabolic systems
Authors: Lin Yi-Hsuan , Liu Hongyu , Liu Xu , Zhang Shen 
Published: September 2022

Abstract
In this paper, we study inverse boundary problems associated with semilinear parabolic systems in several scenarios where both the nonlinearities and the initial data can be unknown. We establish several simultaneous recovery results showing that the passive or active boundary Dirichlet-to-Neumann operators can uniquely recover both of the unknowns, even stably in a certain case. It turns out that the nonlinearities play a critical role in deriving these recovery results. If the nonlinear term belongs to a general C
1 class but fulfilling a certain growth condition, the recovery results are established by the control approach via Carleman estimates. If the nonlinear term belongs to an analytic class, the recovery results are established through successive linearization in combination with special complex geometrical optics solutions for the parabolic system.
Keldysh ionization theory of atoms: mathematical details
Authors: Boroumand N , Thorpe A , Parks A M , Brabec T 
Published: September 2022

Abstract
Keldysh ionization theory is one of the main pillars of strong field physics and attosecond science. It describes non-relativistic ionization rates of hydrogen-like atoms subjected to strong laser fields within the dipole approximation and the length gauge. According to this theory ionization can be described by two regimes: electronic tunneling through a laser-dressed atomic potential (tunnel ionization) and absorption of multiple photons at once (multi-photon ionization). There are many gaps in the mathematical steps and explanations in the original Keldysh paper. Therefore, the goal of this work is to give a detailed re-derivation of ionization rates following Keldysh’s formulation and to fill in the mathematical steps of this beautiful approach so that it is more accessible to a wider audience.
Mechanical properties of 3D-printed pentadiamond
Authors: Felix Levi C , Ambekar Rushikesh S , Woellner Cristiano F , Kushwaha Brijesh , Pal Varinder , Tiwary Chandra S , Galvao Douglas S 
Published: September 2022

Abstract
In this work, we combined fully atomistic molecular dynamics and finite elements simulations with mechanical testings to investigate the mechanical behavior of atomic and 3D-printed models of pentadiamond. Pentadiamond is a recently proposed new carbon allotrope, which is composed of a covalent network of pentagonal rings. Our results showed that the stress–strain (SS) behavior is almost scale-independent. The SS curves of the 3D-printed structures exhibit three characteristic regions. For low-strain values, this first region presents a non-linear behavior close to zero, followed by a well-defined linear behavior. The second regime is a quasi-plastic one and the third one is densification followed by structural failures (fracture). Young’s modulus values decrease from 520 to 486 MPa. The deformation mechanism is bending-dominated and different from the layer-by-layer deformation mechanism observed for other 3D-printed structures. They exhibit good energy absorption capabilities (3.5 MJ kg−1), with some structures even outperforming epoxy Kevlar and TRIP-steel. The structures show better absorption potential than the well-known porous architectures such as honeycomb, schwarzites, and tubulanes and occupy the same region of woven structures in the Ashby chart.
One-step measurement method of five-axis machine tools using a laser tracer
Authors: Hongdong Cong , Jun Zha , Yaolong Chen 
Published: September 2022

Abstract
To improve the motion accuracy of five-axis machine tools, it is important to develop a simple methodology to calibrate all geometric errors. This paper proposes a one-step measurement method to calibrate the five-axis machine tool using a laser tracer. First, a simplified geometric error definition of the five-axis machine tool is presented, which is sufficient and necessary to determine the tool error relative to the workpiece. Subsequently, a one-step measurement method using a laser tracer is proposed, and joint movements of five motion axes are adopted to simultaneously identify all geometric errors. Besides, a measurement path generating method is presented to save the trouble of manually planning the complex measurement path. Compared with the traditional two-step measurement method, the proposed method only needs four laser tracer positions and two reflector offsets, simplifying the measurement procedure and enhancing the measurement accuracy of geometric errors of rotary axes.
Assessment of multi-temperature relaxation models for carbon dioxide vibrational kinetics
Authors: Kosareva A , Kustova E , Mekhonoshina M 
Published: September 2022

Abstract
Several advanced models for multi-temperature vibrational energy relaxation rates are implemented to study adiabatic bath relaxation in carbon dioxide, among them a hybrid model based on state-to-state relaxation rates, the model based on the rigorous Chapman–Enskog theory, and modifications of the Landau–Teller (LT) models. Different sets of rate coefficients for vibrational energy transitions (Schwartz, Slawsky and Herzfeld (SSH) theory, forced harmonic oscillator (FHO) model) are used as well as various techniques for the relaxation time evaluation. Based on isothermal bath simulations it is found that the FHO model provides good agreement with experimentally measured relaxation times. Assessment of relaxation models shows that the three-temperature model based on the Chapman–Enskog theory yields excellent agreement with the detailed hybrid approach while being more computationally efficient; two-temperature models and modifications of the LT formulas cannot provide reliable description of intermode exchanges in polyatomic gases. The choice of the model for transition probabilities is crucial for identifying key relaxation mechanisms. When the FHO model is applied, strongly coupled relaxation in all CO2 modes is found whereas the model of SSH yields overpredicted relaxation rate in the symmetric-bending mode and almost uncoupled slow relaxation in the asymmetric mode. Possible ways for further model validation under glow discharge conditions are discussed.
Witnessing criticality in non-Hermitian systems via entopic uncertainty relation
Authors: Guo You-neng , Wang Guo-you 
Published: September 2022

Abstract
Non-Hermitian systems with exceptional points lead to many intriguing phenomena due to the coalescence of both eigenvalues and corresponding eigenvectors, in comparison to Hermitian systems where only eigenvalues degenerate. In this paper, we propose an alternative and accurate proposal based on the entropy uncertainty relation (EUR) to detect the exceptional points and identify different phases of the non-Hermitian systems. In particular, we reveal a general connection between the EUR and the exceptional points of non-Hermitian system. Compared to the unitary Hermitian dynamics, the behaviors of EUR in the non-Hermitian system are well defined into two different ways depending on whether the system is located in unbroken or broken phase regimes. In the unbroken phase regime where EUR undergoes an oscillatory behavior, while in the broken phase regime where the oscillation of EUR breaks down. Moreover, we identify the critical phenomena of non-Hermitian systems in terms of the EUR in the dynamical limit. It is found that the EUR can detect exactly the critical points of non-Hermitian systems beyond (anti-)PT symmetric systems. Finally, we comment on the prospective experimental situation.
Generation and verification of optical vortices with controlled phase based on coherent beam combining
Authors: Luo Hao , Yang Kaibo , Li Peng , Wen Feng , Gu Yuzong , Wu Zhenkun 
Published: September 2022

Abstract
Optical vortices (OVs) with controllable orbital angular momentum (OAM) distributions have potential applications in optical communication and optical manipulation. However, the source of optical vortices with segmented phase gradients generated by existing methods can be used only at a short distance because of their low power. In this study, based on coherent combining technology, we proposed a method to generate a controlled-phase optical vortex (COV). Compared with traditional OVs, the magnitude and direction of the local OAM of the COV are controllable. The transmission characteristics of the COV in free space were numerically examined using a split-step Fourier transform algorithm. We theoretically and experimentally proved the feasibility of the coherent combining technology to generate an COV and proved that it has the properties of non-diffraction and self-healing.
Learning feedback molecular network models using integer linear programming
Authors: Ozen Mustafa , Emamian Effat S , Abdi Ali 
Published: September 2022

Abstract
Analysis of intracellular molecular networks has many applications in understanding of the molecular bases of some complex diseases and finding effective therapeutic targets for drug development. To perform such analyses, the molecular networks need to be converted into computational models. In general, network models constructed using literature and pathway databases may not accurately predict experimental network data. This can be due to the incompleteness of literature on molecular pathways, the resources used to construct the networks, or some conflicting information in the resources. In this paper, we propose a network learning approach via an integer linear programming formulation that can systematically incorporate biological dynamics and regulatory mechanisms of molecular networks in the learning process. Moreover, we present a method to properly consider the feedback paths, while learning the network from data. Examples are also provided to show how one can apply the proposed learning approach to a network of interest. In particular, we apply the framework to the ERBB signaling network, to learn it from some experimental data. Overall, the proposed methods are useful for reducing the gap between the curated networks and experimental data, and result in calibrated networks that are more reliable for making biologically meaningful predictions.
Electrophysiological and functional signs of Guillain–Barré syndrome predicted by a multiscale neuromuscular computational model
Authors: Cardoso de Oliveira Marina , Naville Watanabe Renato , Kohn André Fabio 
Published: September 2022

Abstract

Objective. The diagnosis of nerve disorders in humans has relied heavily on the measurement of electrical signals from nerves or muscles in response to electrical stimuli applied at appropriate locations on the body surface. The present study investigated the demyelinating subtype of Guillain–Barré syndrome using multiscale computational model simulations to verify how demyelination of peripheral axons may affect plantar flexion torque as well as the ongoing electromyogram (EMG) during voluntary isometric or isotonic contractions. Approach. Changes in axonal conduction velocities, mimicking those found in patients with the disease at different stages, were imposed on a multiscale computational neuromusculoskeletal model to simulate subjects performing unipodal plantar flexion force and position tasks. Main results. The simulated results indicated changes in the torque signal during the early phase of the disease while performing isotonic tasks, as well as in torque variability after partial conduction block while performing both isometric and isotonic tasks. Our results also indicated changes in the root mean square values and in the power spectrum of the soleus EMG signal as well as changes in the synchronization index computed from the firing times of the active motor units. All these quantitative changes in functional indicators suggest that the adoption of such additional measurements, such as torques and ongoing EMG, could be used with advantage in the diagnosis and be relevant in providing extra information for the neurologist about the level of the disease. Significance. Our findings enrich the knowledge of the possible ways demyelination affects force generation and position control during plantarflexion. Moreover, this work extends computational neuroscience to computational neurology and shows the potential of biologically compatible neuromuscular computational models in providing relevant quantitative signs that may be useful for diagnosis in the clinic, complementing the tools traditionally used in neurological electrodiagnosis.
Nonlinear frequency chirping and radial restructure of the ion-temperature-gradient-driven turbulence
Authors: Sun Shiqiao , Wang Zihao , Wang Shaojie , Dai Zongliang 
Published: September 2022

Abstract
Global nonlinear gyrokinetic simulation of the ion-temperature-gradient (ITG) modes clearly demonstrates the nonlinear phase-space resonance, which can be well understood by the nonlinear frequency chirping due to the nonlinear poloidal acceleration of resonant particles by the large-scale structure of radial electric field rather than the widely discussed local shearing effects of the zonal flows. The nonlinear radial restructure of a single-n ITG mode generates multiple daughter-ballooning-modes.
Study on cryogenic deep drawing of 2219 aluminum alloy spherical shell
Authors: Fan Xiaobo , Kong Fanyu , Hong Jiqing , Huang Chuhan 
Published: September 2022

Abstract
In order to meet the urgent needs of aluminum alloy integral shell, a new forming process is required to solve the problem of splitting at room temperature. The plasticity of aluminum alloy is significantly improved at cryogenic temperature, and a novel cryogenic forming method was developed recently. In this paper, a cryogenic forming unit was established to study the cryogenic drawing behavior. The effects of sheet diameter on the wrinkling and deformation behaviors were analyzed by experiments and numerical simulations. The study showed that a spherical shell with a diameter of 200mm and a thickness-diameter-ratio of 1.0% could be formed at -160°C, which split at room temperature. The drawing depth was increased 74.3% at cryogenic temperature. The tendencies of wrinkling and splitting were controlled by the appropriate sheet diameter. It is concluded that cryogenic deep drawing has great potential for forming aluminum alloy integral shells.
DC Microgrid Protection System Based on Positive Channel Metal Oxide Semiconductor
Authors: Peng Yuhang , Wang Lujun 
Published: September 2022

Abstract
DC microgrid has received extensive attention and research because of its natural advantages of improving the consumption efficiency of distributed power sources, and in line with the development trend of clean environment and intelligent operation of power grids in the future. However, short-circuit fault protection of DC microgrid is a major challenge for the development of microgrid. Therefore, the author proposes a DC solid-state circuit breaker with a positive channel metal oxide semiconductor as the main switch, and through simulation, it is verified that this solid-state circuit breaker is feasible. The experimental results show that when the proposed solid-state circuit breaker is normally turned on, the positive channel metal oxide semiconductor is completely turned on, which has no effect on the power flow in the DC microgrid; when a short-circuit fault occurs in the DC microgrid system, the short-circuit current is used to couple the energy, the positive channel metal oxide semiconductor is reliably turned off. The stability and reliability of the system are improved, and it can be applied to the short-circuit protection of the DC microgrid, and has a good application prospect.
Experimental research on ultrasonic A-scan testing technology of composite solid propellant
Authors: Huang Liuchun , Li Jian , Li Bojun 
Published: September 2022

Abstract
To explore the application and development of ultrasonic non-destructive testing technology in composite solid propellant materials, the theory is combined with the principle and method of ultrasonic non-destructive testing technology and the material characteristics of composite solid propellant; Based on ultrasonic A-scan, the experimental testing of propellant grain with multiphase structure, complex properties and high attenuation was carried out using pulse reflection method and penetration method. For the testing system with probe emission frequency of 1 MHz and gain adjustable range of 60 dB, the thickness of propellant grain is recommended to be 10 ~ 50 mm for the pulse reflection method to effectively observe the first bottom echo and the second bottom echo, and the thickness of propellant grain is recommended to be less than or equal to 100 mm for the penetration method to effectively observe the transmission waveform. The coupling modes of ultrasonic testing technology are further analyzed, and the effect test is carried out. In addition, based on the pulse reflection method of direct contact coupling, the sound velocity of propellant grain is measured with probes with different frequencies. The results show that the higher the probe frequency is, the smaller the sound velocity of propellant grain is.
Enhanced blue thermally activated delayed fluorescence with rigid adamantane as non-conjugated linker for space-confined donor-acceptor charge transfer: a theoretical study
Authors: Sheng Yiqi 
Published: September 2022

Abstract
A lack of control over the relative orientation of donor and acceptor moieties in solid films is the main reason for poor electroluminescence efficiency found in most D-σ-A patterns. In this study, adamantane was introduced as the linker for the construction of a D-σ-A system since its rigid but non-conjugated nature. For a systematic study, the same donor (9,9-dimethyl-10-phenyl-9,10-dihydroacridine, DMTPA) and acceptor (2,4,6-triphenyl-1,3,5-triazine, TPZ) block were attached at different sites of the adamantine molecule, forming three kinds of configuration including face-to-face (FF), head-to-tail (HT), and chair (CH) style. DFT/TD-DFT simulation was carried out to investigate the electronic structures, optical characteristics, and charge transfer (ICT) properties of these three designed molecules. Attributed to a non-conjugated adamantane linker, the conjugation between donor and acceptor was disrupted for either of these molecules, resulting in high triplet energy of 2.79, 2.99, and 3.10 eV, respectively. Among them, the face-to-face style molecule presents the smallest ΔEST and greatest charge transfer excitation from donor to acceptor, suggesting an excellent potential for thermal activated delayed fluorescence (TADF). Face-to-face type molecule is a good option for a high-performance blue organic light-emitting diode (OLED) host material based on these results. Our investigation may open a door for designing new host molecule with other donor and acceptor groups to further enhance the efficiency and longevity of OLEDs.