bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent advances in high-strength and high-toughness polyurethanes based on supramolecular interactions
Authors: Xu Jing , Wang Xiaoyue , Ruan Hongwei , Zhang Xinrui , Zhang Yaoming , Yang Zenghui , Wang Qihua , Wang Tingmei
Published: March 2022

This review mainly focuses on the latest development of high-strength and high-toughness polyurethanes based on supramolecular interactions, and provides a comprehensive analysis of the main types, synthetic strategies, and strengthening mechanisms.
High temperature hybrid perovskite multifunctional switching materials constructed through precise molecular design
Authors: He Yueyue , Chen Zhuo , Chen Xiaogang , Zhang Xian-Ming , Fu Dongying
Published: March 2022

Precise molecular design to construct a multifunctional hybrid perovskite switching material, [(R)-N-fluoroethyl-3-quinuclidinol]PbBr3, with a high Tp of 498 K.
Toward efficient electrocatalytic oxygen evolution with a low concentration baking soda activated IrOxsurface in a hydrothermal medium
Authors: Hu Yuling , Ma Chenglong , Du Gan , Gao Hanqing , Tian Xinlong , Yu Huamei , Liao Jianjun , Ge Chengjun , Yang Ji , Sun Wei
Published: March 2022

The presence of HCO3−in a hydrothermal medium enables amorphous IrOxnanoparticles to possess a pseudo-crystalline morphology and further modifies the t2gorbitals, thus substantially increasing the OER catalytic activity.
Denaturation of proteins: electrostatic effects vs. hydration
Authors: Ballauff Matthias
Published: March 2022

A phenomenological approach to the unfolding transition of proteins is given. The model treats quantitatively the effect of electrostatics as well as of hydration (Hofmeister effects).
Extended oligo-cyclopentadithiophene dyes for liquid and solid-state dye-sensitised solar cells
Authors: Jarusarunchai Artit , Liu Xuan , Wu Wenjun , Robertson Neil
Published: March 2022

Extended oligo-cyclopentadithiophene dyes show higher electron recombination resistance and a longer electron lifetime. With unusually thin TiO2 of 0.96 μm, high photocurrent density is achieved for ssDSSCs.
Experimental-based mechanistic study and optimization of hydrothermal liquefaction of anaerobic digestates
Authors: Sudibyo Hanifrahmawan , Pecchi Matteo , Tester Jefferson William
Published: March 2022

Mechanistic-based optimization of hydrothermal liquefaction for simultaneous energy and nutrient recovery provides an opportunity for sustainable agricultural and food industry operations.
Defect-engineered MOF-801 for cycloaddition of CO2 with epoxides
Authors: Gu Yunjang , Anjali Bai Amutha , Yoon Sunghyun , Choe Youngson , Chung Yongchul G. , Park Dae-Won
Published: March 2022

Heterogeneous catalysts based on defective metal–organic frameworks (MOFs) have attracted wide attention due to their facile formation of defects during synthesis.
Biomimetic multifunctional nanozymes enhanced radiosensitization for breast cancer via an X-ray triggered cascade reaction
Authors: Yang Lin , Du Xiao , Qin Yanru , Wang Xueyuan , Zhang Liefeng , Chen Zhimeng , Wang Zhongjie , Yang Xu , Lei Meng , Zhu Yongqiang
Published: March 2022

Design and manufacture of an ultra-small bionic multifunctional nanozyme BSA@CNP/Fe2+ as a radiosensitizer to treat breast cancer.
68Ga-labeled dendrimer-entrapped gold nanoparticles for PET/CT dual-modality imaging and immunotherapy of tumors
Authors: Li Cai , Zhao Lingzhou , Jia Liang , Ouyang Zhijun , Gao Yue , Guo Rui , Song Shaoli , Shi Xiangyang , Cao Xueyan
Published: March 2022

Mechanism for immunotherapy and PET/CT imaging in a mouse sarcoma model.
Vibronic coherences in light harvesting nanotubes: unravelling the role of dark states
Authors: Doria Sandra , Di Donato Mariangela , Borrelli Raffaele , Gelin Maxim F. , Caram Justin , Pagliai Marco , Foggi Paolo , Lapini Andrea
Published: March 2022

Self-assembled ordered structures, such as H- or J-type molecular aggregates of organic chromophores, are extremely appealing materials for optoelectronic applications.
AAA+ proteins: one motor, multiple ways to work
Authors: Lin JiaBei , Shorter James , Lucius Aaron L.
Published: March 2022

Numerous ATPases associated with diverse cellular activities (AAA+) proteins form hexameric, ring-shaped complexes that function via ATPase-coupled translocation of substrates across the central channel. Cryo-electron microscopy of AAA+ proteins processing substrate has revealed non-symmetric, staircase-like hexameric structures that indicate a sequential clockwise/2-residue step translocation model for these motors. However, for many of the AAA+ proteins that share similar structural features, their translocation properties have not yet been experimentally determined. In the cases where translocation mechanisms have been determined, a two-residue translocation step-size has not been resolved. In this review, we explore Hsp104, ClpB, ClpA and ClpX as examples to review the experimental methods that have been used to examine, in solution, the translocation mechanisms employed by AAA+ motor proteins. We then ask whether AAA+ motors sharing similar structural features can have different translocation mechanisms. Finally, we discuss whether a single AAA+ motor can adopt multiple translocation mechanisms that are responsive to different challenges imposed by the substrate or the environment. We suggest that AAA+ motors adopt more than one translocation mechanism and are tuned to switch to the most energetically efficient mechanism when constraints are applied.
Self‐attention mechanism for distributed compressive sensing
Authors: Shu Feng , Zhang Linghua , Ding Yin , Cheng Qin , Wang Xu
Published: March 2022

This letter addresses the joint sparse recovery problem with multiple measurement vectors in compressive sensing (CS). In this letter, it is assumed that the sparse vectors are related to each other but the specific dependencies are unknown. The authors propose a data‐driven approach that relies on a self‐attention mechanism to learn the sparse structure within and between sparse vectors automatically. A greedy method is then used to reconstruct the sparse vectors. The numerical experiments conducted on two real‐world datasets show that the proposed method outperforms the model‐based Bayesian methods and data‐driven method based on long short‐term memory.
Dependence of the vertical‐tunnel‐junction GaAs solar cell on concentration and temperature
Authors: Outes Celia , Fernández Eduardo F. , Seoane Natalia , Almonacid Florencia , García‐Loureiro Antonio J.
Published: March 2022

Modelling the current–voltage (I–V) characteristics of photovoltaic (PV) devices is important for understanding their behaviour and potential. Typically, the single exponential model (SEM) is used because of its simplicity and accuracy. In this work, we validate the SEM for a gallium arsenide (GaAs) vertical‐tunnel‐junction (VTJ) using TCAD software. This cell is the key to overcoming the series resistance limitations of current concentrator solar cells, which can lead to the development of ultra‐high concentrator photovoltaic systems (UHCPV) with concentrations (Cratio) greater than 1000 suns. The results indicate that the SEM is a suitable tool to model the I–V characteristics of the VTJ cell with mean errors lower than 1%. Moreover, the solar cell did not show any limitations regarding the Cratio and temperatures under investigation. In addition, the analysis of the temperature coefficients of the cell demonstrates that their dependency on temperature reduces as Cratio increases. The results of this work suggest that VTJ is a promising solution to produce a new generation of high‐efficiency and low‐cost UHCPV systems.
Theoretical analysis of surface brightness-colour relations for late-type stars using MARCS model atmospheres
Authors: Salsi A. , Nardetto N. , Plez B. , Mourard D.
Published: March 2022

Context. Surface brightness-colour relations (SBCRs) are largely used for general studies in stellar astrophysics and for determining extragalactic distances. Based on a careful selection of stars and a homogeneous methodology, it has been recently shown that the SBCR for late-type stars depends on the spectral type and luminosity class.

Aims. Based on simulated spectra of late-type stars using MARCS model atmospheres, our aim is to analyse the effect of stellar fundamental parameters on the surface brightness. We also compare theoretical and recent empirical SBCRs.

Methods. We used MARCS model atmospheres to compute spectra and obtain the surface brightness of stars. We first explored the parameter space of MARCS (i.e. effective temperature, log g, [Fe/H], microturbulence, and mass) in order to quantify their impact on the surface brightness. Then we considered a relation between the effective temperature and log g for late dwarfs and giants, as well as a solar metallicity, in order to allow a consistent comparison of theoretical and empirical SBCRs.

Results. We find that the SBCR is not sensitive to the microturbulence and mass. The effect of metallicity on the SBCR is found to be larger for dwarfs than for giants. It is also larger when considering larger V - Ks values. We also find that a difference of 0.5 dex in metallicity between Galactic and LMC SBCRs does not affect the recent LMC distance determination, based on eclipsing binaries, by more than 0.4%. By comparing theoretical with empirical SBCRs, we find a good agreement of less than 2σ for F5-K7 dwarfs and giants stars, while a larger discrepancy is found for M dwarfs and giants (about 4-6σ). The surface gravity properties, as modelled in MARCS, explain the differences in the empirical SBCRs in terms of class. We finally find that theoretical and empirical SBCRs for Cepheids are consistent.

Conclusions. Carefully considering metallicity and log g is mandatory when calibrating or using SBCRs.
Luminosity selection for gamma-ray bursts
Authors: Banerjee S. , Guetta D.
Published: March 2022

Aims.There exists inevitable scatter in the intrinsic luminosity of gamma-ray bursts (GRBs). If there is relativistic beaming in the source, viewing angle variation necessarily introduces variation in the intrinsic luminosity function (ILF). Scatter in the ILF can cause selection bias where sources detected at distance have a greater median luminosity than those detected close by. Median luminosity divides any given population into equal halves. When the functional form of a distribution is unknown, it can be a more robust diagnostic than those that use trial functional forms.

Method.In this work, we employ a statistical test based on median luminosity and use it to test a class of models for GRBs. We assume that the GRB jet has a finite opening angle and that the orientation of the GRB jet is random relative to the observer. We calculateLmedianas a function of redshift by simulating GRBs empirically and theoretically, and use the luminosity-vs.-redshiftSwiftdata in order to compare the theoretical results with the observed ones. The method accounts for the fact that there may be GRBs that go undetected at some redshifts.

Results.We find thatLmedianis extremely insensitive to the on-axis (i.e., maximal) luminosity of the jet.
„Sie schon wieder ?!“ – Kolumne
Authors: Schiewack Michael
Published: March 2022

Eine ältere Dame bekommt Ergotherapie verordnet, aber irgendwie will der Funke zum Therapeuten nicht überspringen. Michael Schiewack muss seinen ganzen Charme aufbringen, um das Eis zu brechen.
Wie lässt sich die Patientin Erde retten? – Planetary Health
Authors: Mischner Julia
Published: March 2022

Das sich verändernde Klima nimmt direkten und indirekten Einfluss auf die Gesundheit der weltweiten Bevölkerung. Die Planetary Health betrachtet die menschlichen und die natürlichen Systeme der Erde und macht deutlich: Wir müssen unseren Planeten schützen, um auch unsere Gesundheit und die der nachfolgenden Generationen zu garantieren.
Im Herzen der Ergotherapie – Betätigungsdimensionen: Being und Doing
Authors: Kranz Florence
Published: March 2022

Dreh- und Angelpunkt der Ergotherapie bilden bedeutungsvolle Betätigungen. Sie sind viel mehr als „nur“ Doing, also konkretes Tun. Florence Kranz beleuchtet, welche vier Dimensionen eine Betätigung kennzeichnen und wie diese mit Lebensqualität zusammenhängen. Teil 1 startet mit Being und Doing, Teil 2 wird sich um Becoming und Belonging drehen.
Rate of pancreatic cancer following a negative endoscopic ultrasound and associated factors
Authors: King Dominic , Kamran Umair , Dosanjh Amandeep , Coupland Ben , Mytton Jemma , Leeds John S. , Nayar Manu , Patel Prashant , Oppong Kofi W. , Trudgill Nigel J.
Published: March 2022

Background Data are limited regarding pancreatic cancer diagnosed following a pancreaticobiliary endoscopic ultrasound (EUS) that does not diagnose pancreatic cancer. We have studied the frequency of, and factors associated with, post-EUS pancreatic cancer (PEPC) and 1-year mortality.

Methods Between 2010 and 2017, patients with pancreatic cancer and a preceding pancreaticobiliary EUS were identified in a national cohort using Hospital Episode Statistics. Patients with a pancreaticobiliary EUS 6–18 months before a later pancreatic cancer diagnosis were the PEPC cases; controls were those with pancreatic cancer diagnosed within 6 months of pancreaticobiliary EUS. Multivariable logistic regression models examined the factors associated with PEPC and a Cox regression model examined factors associated with 1-year cumulative mortality.

Results 9363 pancreatic cancer patients were studied; 93.5 % identified as controls (men 53.2 %; median age 68 [interquartile range (IQR) 61–75]); 6.5 % as PEPC cases (men 58.2 %; median age 69 [IQR 61–77]). PEPC was associated with older age (≥ 75 years compared with < 65 years, odds ratio [OR] 1.42, 95 %CI 1.15–1.76), increasing co-morbidity (Charlson co-morbidity score > 5, OR 1.90, 95 %CI 1.49–2.43), chronic pancreatitis (OR 3.13, 95 %CI 2.50–3.92), and diabetes mellitus (OR 1.58, 95 %CI 1.31–1.90). Metal biliary stents (OR 0.57, 95 %CI 0.38–0.86) and EUS-FNA (OR 0.49, 95 %CI 0.41–0.58) were inversely associated with PEPC. PEPC was associated with a higher cumulative mortality at 1 year (hazard ratio 1.12, 95 %CI 1.02–1.24), with only 14 % of PEPC patients (95 %CI 12 %–17 %) having a surgical resection, compared with 21 % (95 %CI 20 %–22 %) of controls.

Conclusions PEPC occurred in 6.5 % of patients and was associated with chronic pancreatitis, older age, more co-morbidities, and specifically diabetes mellitus. PEPC was associated with a worse prognosis and lower surgical resection rates.
A molecular dynamics study of laser-excited gold
Authors: Molina Jacob M. , White T. G.
Published: March 2022

The structural evolution of laser-excited systems of gold has previously been measured through ultrafast MeV electron diffraction. However, there has been a long-standing inability of atomistic simulations to provide a consistent picture of the melting process, leading to large discrepancies between the predicted threshold energy density for complete melting, as well as the transition between heterogeneous and homogeneous melting. We make use of two-temperature classical molecular dynamics simulations utilizing three highly successful interatomic potentials and reproduce electron diffraction data presented by Mo et al. [Science 360, 1451–1455 (2018)]. We recreate the experimental electron diffraction data, employing both a constant and temperature-dependent electron–ion equilibration rate. In all cases, we are able to match time-resolved electron diffraction data, and find consistency between atomistic simulations and experiments, only by allowing laser energy to be transported away from the interaction region. This additional energy-loss pathway, which scales strongly with laser fluence, we attribute to hot electrons leaving the target on a timescale commensurate with melting.
First-principles prediction of magnetic properties in Fe(Co,Ni)(C,N)0.5 alloys
Authors: Kota Yohei , Sakuma Akimasa
Published: March 2022

To explore a candidate for rare-earth-free magnets, the effects of the light elements (C,N) addition on the magnetic properties in FeCo and FeNi ordered alloys were examined using first-principles calculations. Among Fe(Co,Ni)(C,N)0.5 alloys, we found that FeNiC0.5 is the most promising, because its uniaxial magnetic anisotropy constant Ku is expected to be 3.0 MJ/m3 (five times Ku of L10-type FeNi) and the increase in the Curie temperature TC by the addition of C was observed. The mechanism for the enhancement of Ku and TC can be understood by the basic concepts of the physics of magnetism. Despite being nonmagnetic themselves, light elements have the potential to improve the fundamental properties of magnetic materials.
π
-magnetism and spin-dependent transport in boron pair doped armchair graphene nanoribbons
Authors: Zhang Peina , Li Xinlu , Dong Jianting , Zhu Meng , Zheng Fanxing , Zhang Jia
Published: March 2022

Carbon-based magnetic nanostructures have long spin coherent length and are promising for spintronics applications in data storage and information processing. Recent experiments demonstrate that a pair of substitutional boron atoms (B2) doped 7-atom-wide armchair graphene nanoribbons (B2-7AGNRs) have intrinsic magnetism, providing a quasi-1D magnetic material platform for spintronics. In this work, we demonstrate that the magnetism in B2-7AGNRs is contributed by π-electrons, originating from the imbalance of electrons in two spin channels in response to boron dopants. The spin-dependent transport across single and double boron pair doped 7AGNRs (B2-7AGNRs and 2B2-7AGNRs) by constructing lateral graphene nanoribbon heterojunctions has been investigated by using first-principles calculations. We show that for B2-7AGNRs with spin splitting π-electronic states near the Fermi level, by applying a bias voltage, one can obtain a current spin polarization over 90% and a negative differential resistance effect. For 2B2-7AGNRs, two spin centers have been found to be antiferromagnetically coupled. We demonstrate a magnetoresistance effect over 15 000% by setting those two spin centers to be ferromagnetic and antiferromagnetic alignments. Based on the above spin-polarized transport properties, we reveal that GNR heterojunctions based on B2-7AGNRs could be potentially applied in quasi-1D spintronic devices.
Explaining reaction coordinates of alanine dipeptide isomerization obtained from deep neural networks using Explainable Artificial Intelligence (XAI)
Authors: Kikutsuji Takuma , Mori Yusuke , Okazaki Kei-ichi , Mori Toshifumi , Kim Kang , Matubayasi Nobuyuki
Published: March 2022

A method for obtaining appropriate reaction coordinates is required to identify transition states distinguishing the product and reactant in complex molecular systems. Recently, abundant research has been devoted to obtaining reaction coordinates using artificial neural networks from deep learning literature, where many collective variables are typically utilized in the input layer. However, it is difficult to explain the details of which collective variables contribute to the predicted reaction coordinates owing to the complexity of the nonlinear functions in deep neural networks. To overcome this limitation, we used Explainable Artificial Intelligence (XAI) methods of the Local Interpretable Model-agnostic Explanation (LIME) and the game theory-based framework known as Shapley Additive exPlanations (SHAP). We demonstrated that XAI enables us to obtain the degree of contribution of each collective variable to reaction coordinates that is determined by nonlinear regressions with deep learning for the committor of the alanine dipeptide isomerization in vacuum. In particular, both LIME and SHAP provide important features to the predicted reaction coordinates, which are characterized by appropriate dihedral angles consistent with those previously reported from the committor test analysis. The present study offers an AI-aided framework to explain the appropriate reaction coordinates, which acquires considerable significance when the number of degrees of freedom increases.
Automation in diagnostic microbiology
Authors: Olma Tom
Published: March 2022

Automation in diagnostic microbiology has provided accessibility to technology overcoming the delays inherent in culture-based technology and providing options to centralisation via use of digital imaging to interpret and report culture plates which enables cultures to be shared over the internet opening the virtual diagnostic microbiology laboratory. Automation is a continuous process which precipitates faster results and invites the diagnostic laboratory into a continuous processing, 24/7 world optimising what it has to offer for improved turnaround time (TAT) and improved workload management. While molecular technology was able to decrease TAT of results it was initially specialised and not freely available to the diagnostic microbiology laboratory becoming more a centralised subspeciality. The automation of molecular methods released the technology to be able to be decentralised and provide greater local access and community benefits from the technology and providing equity of community access to the technology. Thanks to automation, diagnostic microbiology is at the forefront of opening the availability of advances in testing to the broader community via decentralising technology and sharing technology in the virtual diagnostic microbiology laboratory.
Pluto near the edge of chaos
Authors: Malhotra Renu , Ito Takashi
Published: March 2022

Significance

The dwarf planet, Pluto, has stirred the imagination of the public and of planetary scientists due to its many unusual properties. Among these properties is its Neptune-crossing orbit whose stability is owed to an orbital resonance with Neptune. Less well understood is the role of the other planets. We demonstrate that the orbital architecture of the giant planets lies within a narrow niche in which Pluto-like orbits are practically stable on gigayear timescales, whereas nearby are strongly chaotic orbits. Pluto is witness to the dynamical history of the solar system; quantifying its proximity to strong chaos and dynamical instability can enable quantitative constraints on its own dynamical history as well as that of the solar system.
Discourse-driven asymmetries between embedded interrogatives and relative clauses in West Germanic
Authors: Bacskai-Atkari Julia
Published: March 2022

The article examines embedded constituent questions and relative clauses in West Germanic, arguing that asymmetries regarding doubly filled COMP patterns are due to information-structural differences. While both clause types involve operator movement, they differ crucially regarding the information-structural status of the operator: in interrogatives, the operator can be associated with discourse-new information, while in relative clauses the operator is discourse-old and can be potentially left out. This asymmetry regarding information-structural properties has further important consequences. First, doubling patterns involving an overt operator and an overt complementiser emerge across West Germanic languages in embedded questions but not in relative clauses. Second, the reanalysis of the operator into a complementiser is attested in relative clauses but not in embedded interrogatives.
Vector-valued spline method for the spherical multiple-shell electro-magnetoencephalography problem
Authors: Leweke S , Hauk O , Michel V
Published: March 2022

Human brain activity is based on electrochemical processes, which can only be measured invasively. Thus, quantities such as magnetic flux density (MEG) or electric potential differences (EEG) are measured non-invasively in medicine and research. The reconstruction of the neuronal current from the measurements is a severely ill-posed problem though the visualization of the cerebral activity is one of the main research tools in cognitive neuroscience. Here, using an isotropic multiple-shell model for the human head and a quasi-static approach for the electro-magnetic processes, we derive a novel vector-valued spline method based on reproducing kernel Hilbert spaces in order to reconstruct the current from the measurements. The presented method follows the path of former spline approaches and provides classical minimum norm properties. Besides, it minimizes the (infinite-dimensional) Tikhonov–Philips functional which handles the instability of the inverse problem. This optimization problem reduces to solving a finite-dimensional system of linear equations without loss of information, due to its construction. It results in a unique solution which takes into account that only the harmonic and solenoidal component of the neuronal current affects the measurements. Furthermore, we prove a convergence result: the solution achieved by the novel method converges to the generator of the data as the number of measurements increases. The vector splines are applied to the inversion of three synthetic test cases, where the irregularly distributed data situation could be handled very well. Combined with five parameter choice methods, numerical results are shown for synthetic test cases with and without additional Gaussian white noise. Former approaches based on scalar splines are outperformed by the novel vector splines results with respect to the normalized root mean square error. Finally, results for real data acquired during a visual stimulation task are demonstrated. They can be computed quickly and are reasonable with respect to physiological expectations.
Thin film block copolymer self-assembly for nanophotonics
Authors: Kulkarni Ashish A , Doerk Gregory S
Published: March 2022

The nanophotonic engineering of light–matter interactions has profoundly changed research behind the design and fabrication of optical materials and devices. Metasurfaces—arrays of subwavelength nanostructures that interact resonantly with electromagnetic radiation—have emerged as an integral nanophotonic platform for a new generation of ultrathin lenses, displays, polarizers and other devices. Their success hinges on advances in lithography and nanofabrication in recent decades. While existing nanolithography techniques are suitable for basic research and prototyping, issues of cost, throughput, scalability, and substrate compatibility may preclude their use for many metasurface applications. Patterning via spontaneous self-assembly of block copolymer thin films offers an enticing alternative for nanophotonic manufacturing that is rapid, inexpensive, and applicable to large areas and diverse substrates. This review discusses the advantages and disadvantages of block copolymer-based nanopatterning and highlights recent progress in their use for broadband antireflection, surface enhanced Raman spectroscopy, and other nanophotonic applications. Recent advances in diversification of self-assembled block copolymer nanopatterns and improved processes for enhanced scalability of self-assembled nanopatterning using block copolymers are also discussed, with a spotlight on directions for future research that would enable a wider array of nanophotonic applications.
Reverberation clutter signal suppression in ultrasound attenuation estimation using wavelet-based robust principal component analysis
Authors: Lok U-Wai , Gong Ping , Huang Chengwu , Tang Shanshan , Zhou Chenyun , Yang Lulu , Watt Kymberly D , Callstrom Matthew , Trzasko Joshua D , Chen Shigao
Published: March 2022

Objective. Ultrasound attenuation coefficient estimation (ACE) has diagnostic potential for clinical applications such as quantifying fat content in the liver. Previously, we have proposed a system-independent ACE technique based on spectral normalization of different frequencies, called the reference frequency method (RFM). This technique does not require a well-calibrated reference phantom for normalization. However, this method may be vulnerable to severe reverberation clutter introduced by the body wall. The clutter superimposed on liver echoes may bias the estimation. Approach. We proposed to use robust principal component analysis, combined with wavelet-based sparsity promotion, to suppress the severe reverberation clutters. The capability to mitigate the reverberation clutters was validated through phantom and in vivo studies. Main Results. In the phantom studies with added reverberation clutters, higher normalized cross-correlation and smaller mean absolute errors were attained as compared to RFM results without the proposed method, demonstrating the capability to reconstruct tissue signals from reverberations. In a pilot patient study, the correlation between ACE and proton density fat fraction (PDFF), a measurement of liver fat by MRI as a reference standard, was investigated. The proposed method showed an improvement of the correlation (coefficient of determination, R = 0.82) as compared with the counterpart without the proposed method (R = 0.69). Significance: The proposed method showed the feasibility of suppressing the reverberation clutters, providing an important basis for the development of a robust ACE with large reverberation clutters.
Full-volume three-component intraventricular vector flow mapping by triplane color Doppler
Authors: Vixège Florian , Berod Alain , Courand Pierre-Yves , Mendez Simon , Nicoud Franck , Blanc-Benon Philippe , Vray Didier , Garcia Damien
Published: March 2022

Objective. Intraventricular vector flow mapping (iVFM) is a velocimetric technique for retrieving two-dimensional velocity vector fields of blood flow in the left ventricular cavity. This method is based on conventional color Doppler imaging, which makes iVFM compatible with the clinical setting. We have generalized the iVFM for a three-dimensional reconstruction (3D-iVFM). Approach. 3D-iVFM is able to recover three-component velocity vector fields in a full intraventricular volume by using a clinical echocardiographic triplane mode. The 3D-iVFM problem was written in the spherical (radial, polar, azimuthal) coordinate system associated to the six half-planes produced by the triplane mode. As with the 2D version, the method is based on the mass conservation, and free-slip boundary conditions on the endocardial wall. These mechanical constraints were imposed in a least-squares minimization problem that was solved through the method of Lagrange multipliers. We validated 3D-iVFM in silico in a patient-specific CFD (computational fluid dynamics) model of cardiac flow and tested its clinical feasibility in vivo in patients and in one volunteer. Main results. The radial and polar components of the velocity were recovered satisfactorily in the CFD setup (correlation coefficients,

r

 = 0.99 and 0.78). The azimuthal components were estimated with larger errors (

r

 = 0.57) as only six samples were available in this direction. In both in silico and in vivo investigations, the dynamics of the intraventricular vortex that forms during diastole was deciphered by 3D-iVFM. In particular, the CFD results showed that the mean vorticity can be estimated accurately by 3D-iVFM. Significance. Our results tend to indicate that 3D-iVFM could provide full-volume echocardiographic information on left intraventricular hemodynamics from the clinical modality of triplane color Doppler.
A novel iron-based superconductor synthesized by the ion exchange technique
Authors: Hu G B , Shi M Z , Wang W X , Zhu C S , Luo X G , Chen X H
Published: March 2022

The superconductivity of the FeSe-based superconductor is extremely sensitive to Fe vacancies in the FeSe plane. In order to reduce the formation of Fe vacancies in the FeSe plane, various low-temperature methods are developed. However, it is still complex and time consuming to control the Fe vacancies concentration. Here, a hybrid iron-based superconductor, Li0.21Se0.05(EG)0.26FeSe (EG: ethylene glycol, C2H6O2), is synthesized by a solvothermal ion-exchange technique using a nearly vacancy-free precursor of (TBA)0.3FeSe as the matrix. Bulk superconductivity with transition temperature (T
c) of 30 K is confirmed by the characterization with the magnetic susceptibility and resistivity measurements. Compared with the pristine FeSe single crystal, x-ray photoelectron spectroscopy results show a decrease of the Fe valence, indicating that electron doping to FeSe plane accounts for the increase of the T
c. Our result suggests that (TBA)0.3FeSe, a nearly vacancy-free precursor with a large distance between the adjacent FeSe planes, is a good template candidate for the synthesis of other hybrid iron-based superconductors using the ion exchange technique.
Solvent-conjugation-induced ultrafast dynamics of enhanced reverse saturable absorption in lead phthalocyanine derivatives solutions
Authors: Du Xinchen , Zhang Yunfeng , Wang Chunrui , Chen Fei , Li Qingyi , Shao Junfeng , Wang Rui , Liu Haibo , Jin Mingxing
Published: March 2022

With the continued development of high-power laser technology, research on laser protection has become extremely important. In this study, an analysis of Z-scan and femtosecond transient absorption spectra data for lead (II) tetrakis (4-cumylphenoxy) phthalocyanine (4-PbPc) solutions prepared using different concentrations and solvents established that charge transfer plays an important role in the optical limiting dynamics of this molecule. Based on the correlation of decay-associated difference spectra (DADS) for different decay channels, it was confirmed that greater charge transfer efficiency was associated with more highly conjugated solvent molecules. In a dilute solution, the polarity of the solvent molecules will influence the optical limiting performance of the solution to an extent, whereas in a highly concentrated solution, the degree of conjugation of the solvent molecules is the main influence. Therefore, the more highly conjugated the solvent and the higher the solution concentration, the higher the excited state absorption cross-section and effective two-photon absorption coefficient, and the longer the triplet lifetime. These results should provide theoretical guidance and experimental clues for the design of materials with better optical limiting performance and promote the further development of laser protection.
Overview on the management of radioactive waste from fusion facilities: ITER, demonstration machines and power plants
Authors: Gonzalez de Vicente Sehila M. , Smith Nicholas A. , El-Guebaly Laila , Ciattaglia Sergio , Di Pace Luigi , Gilbert Mark , Mandoki Robert , Rosanvallon Sandrine , Someya Youji , Tobita Kenji , Torcy David
Published: March 2022

In the absence of official standards and guidelines for nuclear fusion plants, fusion designers adopted, as far as possible, well-established standards for fission-based nuclear power plants (NPPs). This often implies interpretation and/or extrapolation, due to differences in structures, systems and components, materials, safety mitigation systems, risks, etc. This approach could result in the consideration of overconservative measures that might lead to an increase in cost and complexity with limited or negligible improvements. One important topic is the generation of radioactive waste in fusion power plants. Fusion waste is significantly different to fission NPP waste, i.e. the quantity of fusion waste is much larger. However, it mostly comprises low-level waste (LLW) and intermediate level waste (ILW). Notably, the waste does not contain many long-lived isotopes, mainly tritium and other activation isotopes but no-transuranic elements. An important benefit of fusion employing reduced-activation materials is the lower decay heat removal and rapid radioactivity decay overall. The dominant fusion wastes are primarily composed of structural materials, such as different types of steel, including reduced activation ferritic martensitic steels, such as EUROFER97 and F82H, AISI 316L, bainitic, and JK2LB. The relevant long-lived radioisotopes come from alloying elements, such as niobium, molybdenum, nickel, carbon, nitrogen, copper and aluminum and also from uncontrolled impurities (of the same elements, but also, e.g. of potassium and cobalt). After irradiation, these isotopes might preclude disposal in LLW repositories. Fusion power should be able to avoid creating high-level waste, while the volume of fusion ILW and LLW will be significant, both in terms of pure volume and volume per unit of electricity produced. Thus, efforts to recycle and clear are essential to support fusion deployment, reclaim resources (through less ore mining) and minimize the radwaste burden for future generations.
Study about the chip formation in the turning process using the finite element analysis
Authors: Pop Alina Bianca , Țîţu Aurel Mihail
Published: March 2022

At this time, there is a significant interest in the chip shape and formation at the international level, an issue studied based on mathematical calculations, experiments, and finite element analysis. The analysis of the chip formation process showed that the thickness of the undetached chip also varies according to the rake angle of the cutting tool, and using 3D models to analyze the chip formation process demonstrates this fact. Following the research, a study was conducted in which an analysis of the chip morphology is presented. Using Deform 2D application, a finite element simulation - a comparative analysis of the chip formation was performed when the value of the clearance angle varies. The increasing variety of cutting radius values has an influence on the way the chips are formed in terms of thickness, which generate differences in its shape. Following the study, a series of conclusions and own findings emerged that with the increase of the cutting-edge radius, the stress distribution is radial over a greater area of the part, reason for which the deformation of the chip is smaller. Arguments have also been made on distribution of the temperature, which is directly influenced by the shape of the tool, influencing the temperature of the generated chip. The results also show that with the increase of the cutting-edge radius of the tool, there is a tendency for the detached chip to settle.
Corrective profiling method for tools that generate by enwrapping
Authors: Moroşanu G A , Teodor V G , Crăciun R
Published: March 2022

There are known methods of corrective profiling of tools, which can predict the quality of parts generating obtained with cutting tools that process by enwrapping. The purpose of this profiling is to avoid errors caused by improper profiles of generating tools, using the so-called method of "reverse generation", which is based on the reproduction of the relative movement between the tool and the part, but in which the tool profile is known, and the goal is determining the part’s profile. The method presented in this paper uses the "virtual pole" method to profile the tools generating by enwrapping, by the rolling method and avoids the need to explicitly write the enveloping condition. This paper demonstrates the possibility of applying this method to the profiling of gear-shaped tools and presents the application of the proposed algorithm for a tool whose profile was determined directly by measurement. The numerical application developed demonstrates the ability of the method to simply solve the problems related to the corrective profiling of the tools that generate by rolling.
Experimental results on the quality of the surface on turning with inclined tangential cutting line
Authors: Puriciuc M V , Cioară R , Pisarciuc C
Published: March 2022

The authors devised an innovative processing method, called turning with inclined tangential cutting line. To validate the concept a suitable tool was made, and experimental research was performed in order to evaluate the results from the perspective of the quality of the generated surfaces. The research program involved the processing of various materials with operating modes characterized by the same depth of cut, but different speeds and feed rates. The roughness of the obtained surfaces was measured using a high-performance electronic roughness meter. For comparison, processing under similar conditions was performed using a normal tool. This paper presents a number of experimental results and relevant conclusions supported by them. Also, some directions of further research are highlighted. The authors considered both logical and necessary outcomes after critical analysis of results and in terms of extending the parameters that characterize the designed process.
Application of zirconium in dentistry for creating dental crowns
Authors: Pavlova D , Filchev R , Dovramadjiev T
Published: March 2022

Modern dental healthcare is unthinkable without the use of biocompatible materials. They must have the necessary mechanical properties to ensure the strength of dental structures, as well as be as acceptable as possible by the human body. In recent years, there has been an increase in the application of zirconium dioxide (ZrO2) material to metal ceramics in the manufacture of dental crowns, bridges and others. This has its natural continuation of the evolution of dental materials, which significantly improve human health not only in the oral area but also in complex, where the goal is to minimize the external contact of biological tissue with certain metal components. The present study shows the application of zirconium in the development of crowns on dental implants. Technological working hours are optimized. The process is followed in detail, highlighting important points that accompany the practical part of making the dental crown through the use of modern technologies in design. To objectively present the information in the study, a set of photographic material is presented, visualizing in detail important moments in the production of the zirconium crown.
An aerodynamic theoretical study on exterior accessories of intervention vehicles
Authors: Ilea L , Iozsa D , Fratila G
Published: March 2022

In the last decades, an extended set of restrictions and requirements for the automotive industry were imposed due to the increased concern for the environment and the population’s health. Their purpose is to gradually reduce the level of emissions. Personal and commercial vehicles represent an important percent of total industry emissions footprint [1], however, intervention vehicles also bring a significant contribution in this area. The current paper proposes a theoretical study from an aerodynamic point of view of generic exterior equipment such as warning lights, sound devices, etc. for different body types such as sedan, hatchback, SUV, trucks. While the base vehicle complies with standard regulations regarding the emissions, the paper will highlight the significant impact brought by these elements when integrated on the vehicle, outside the manufacturer’s development process. The paper will also show the relationship between equipment’s dimension and position and the aerodynamic coefficient, though in fuel consumption and overall emissions performance.
Nondestructive evaluation of nanostructured components using Eddy current microsensor
Authors: Iftimie N , Steigmann R , Faktorova D , Savin A
Published: March 2022

Nanostructured materials (NMs) are used in the manufacture of microsensors and some MEMS devices, include nanoscale wires, carbon nanotubes, biomaterials, etc. Nondestructive evaluation of structural integrity of NMs can be carried out by optical (SEM, EBDS) and electromagnetic methods (eddy current). Due to small dimensions of the objects to be tested, the eddy current sensors used in detection of possible discontinuities requires miniaturization so that the answer in amplitude and phase shall allow their localization. In the case of thin tubes made of 304 hard stainless steel, with outer diameters 332μm and wall thickness 38 μm used in medical devices, intended for special catheters, their small dimensions and possible discontinuities require encircling sensor working at high frequencies of the order of MHz. The paper presents the investigation of small diameter tubes using an Eddy current microsensor and the results obtained at the detection of artificial flaws in order to increase the probability of detection (POD), for a high reliability coefficient.
A research of new potential vibration cancellation techniques with the use of piezo stacks
Authors: Harazin J , Wróbel A
Published: March 2022

Piezoelectric materials offer an ability to exchange energy between electrical and mechanical systems with fair ease, by using the direct and inverse piezoelectric effect. Piezoelectric transceivers, sensors, microphones, actuators or active acoustic noise cancellation devices are some of many applications for piezoelectric materials. Due to the natural ability of the material to convert electricity and mechanical strain, solutions based on piezoelectric materials are often compact and allow applications on micro scales. This article aims at expanding the applicability of piezoelectric materials to dampen vibrations of broader spectrum and bigger amplitudes, in hopes for finding new possible solutions for damping vibrations generated by heavy duty equipment or machines associated with manufacturing processes. The study involves parallel attempts at creating algorithms and mathematical models using classical mathematical algebra and deep learning techniques to actively dampen incoming vibrations with the use of piezoelectric plates. The novelty of this study would involve using piezoelectric plates of different sizes and properties in a single stack, to dampen the frequencies and amplitudes of incoming vibrations.
Turning tool with tangential cutting line. Concept and constructive solution
Authors: Puriciuc M V , Cioară R , Pisarciuc C
Published: March 2022

New ways to increase the performance of metal cutting are constantly being sought. Although diverse and increasingly performing tools are designed and used, especially those with inserts, rarely new processing schema are identified in order to ensure favourable conditions to obtain a higher quality for generated surfaces. The paper presents a particular and innovative processing schema, as well as a specific tool for machining cylindrical surfaces by turning with a tangential cutting line. The active part of the latter is an insert whose cutting line is placed frontally in a vertical plane and considerably inclined in relation to the horizontal plane. In order to validate the concept, a variation of the tool has been developed and tested, one that doesn’t present the option of adjusting the angle of the cutting line. The success thus achieved prompted the design of a tool that allows the cutting line to be tilted at any angle in relation to the horizontal plane. A patent application has been filed in this regard.
Using 3D scanning in assessing the dimensional accuracy of mechanically machined parts
Authors: Afteni Cezarina , Paunoiu Viorel , Afteni Mitica , Teodor Virgil
Published: March 2022

In recent years, productivity and competitiveness have played a major role in manufacturing. To improve these aspects, many companies use computer-aided inspection (CAI) technologies. Inspection of parts, using 3D scanning technologies, is one the most modern and competitive ways to ensure the quality control of products. This paper presents a study on the assessment of the machined parts’ dimensional accuracy. An Atos Core device for 3D scanning of the part was used. The Atos device allows a non-contact inspection of the part’s entire surface, generating a very dense point cloud, which stores, with great accuracy, all the details of the inspected object. The machined part is compared with its numerical model, obtained by computer-aided design (CAD). The accuracy of the machining was proven to be very good, and the inspection’s result proves that the dimensions of the piece fall within the tolerance limits. A complete inspection of the piece, using 3D scanning, guarantees a fast and accurate quality control, thus reducing the production times.