bluuebunny/crossref_metadata_2025 huggingface dataset:
What does professional experience have to offer?
Authors: Ho Chen-En
Published: January 2021

This study investigated the impact of professional experience on
the process and product of sight interpreting/translation (SiT). Seventeen
experienced interpreters, with at least 150 days’ professional experience, and
18 interpreting students were recruited to conduct three tasks: silent reading,
reading aloud, and SiT. All participants had similar interpreter training
backgrounds. The data of the SiT task are reported here, with two
experienced interpreters (both AIIC members) assessing the participants’
inter­pretations on accuracy and style, which includes fluency and other
paralinguistic performance. The findings show that professional experience
contributed to higher accuracy, although there was no between-group difference
in the mean score on style, overall task time, length of the SiT output, and
mean fixation duration of each stage of reading. The experienced practitioners
exhibited more varied approaches at the beginning of the SiT task, with some
biding their time longer than the others before oral production started, but
quality was not affected. Moving along, the practitioners showed better language
flexibility in that their renditions were faster, steadier, and less disrupted
by pauses and the need to read further to maintain the flow of
interpretation.
Influence of vanadium, boron and titanium on hot ductility of high Al, TWIP steels
Authors: Kang S. E. , Kang M. H. , Mintz B.
Published: January 2021

High Al, twinning induced plasticity (TWIP) steels have high tensile strengths and excellent ductility but low yield strengths compared to other advanced high strength steels and this has limited their application. A.Vanadium addition is a possible answer but cracking on casting is a worry. Hot tensile tests were therefore performed on 1.5% Al, TWIP steels with vanadium levels approximately 0.05–0.7% (all wt-%). Only the 0.05% vanadium steel gave acceptable hot ductility but the room temperature yield strength was too low. In contrast, the Ti–B high 0.5% V steel which was as well as able to give a high yield strength due to precipitation hardening by vanadium carbide gave better ductility by boron segregating to the boundaries and strengthening them.
Microstructure control and properties of cold-sprayed titanium and its alloy coatings
Authors: Zhou Hongxia
Published: January 2021

Compared to thermal spraying, the cold spray (CS) process features virtually oxide-free coatings without thermal defects and residual stress, and it is suitable for processing Ti and its alloys. This review focuses on microstructure control and current properties of CSed Ti and its alloys coating to elucidate and expand their applications. A critical overview of the main processing parameters governing the microstructure of the coating has been presented and discussed, combined with some useful results from the studies reported by various research groups. The porosity and mechanical properties of CSed Ti and its alloy coatings have been summarised. A synopsis of the measurement techniques of each property has also been presented herein.
Air shooting competition effects on visual skills depending on the sport level
Authors: Mon‐López Daniel , Bernardez‐Vilaboa Ricardo , Sillero‐Quintana Manuel , Alvarez Fernandez‐Balbuena Antonio
Published: January 2021

Olympic shooting is a sport with high demands of accuracy. Minimal visual errors could be related to performance losses. However, not all visual skills have been studied in depth in this sport. The main objectives of this study were to compare differences in shooters’ visual skills by level and to analyze the competition effect on them. Sixty‐six participants were distributed in three groups (non‐athletes, elite and non‐elite). Eleven visual variables were tested in four skills groups (visual acuity, heterophoria, accommodation functions and other visual skills). The data were collected through a pre‐ and post‐competition simulation test. The results of the study showed differences between groups by shooting sport level. In general, shooters had higher visual acuity values than non‐athletes p < .001 with large size effects (d between 1.01 and 2.35), and elite shooters presented higher values of accommodation than non‐elite shooters p < .05 with large size effects (d between 0.88 and 0.97). Furthermore, different visual skills were modified after competition depending on the shooting level. Specifically, visual accommodation skills were only improved in elite shooters. Finally, our study suggests that elite shooters employ different visual strategies or skills to non‐elite shooters and that shooting activity is closely related to some specific visual skills. This aspect should be considered by coaches in the design of optimal visual trainings and improve the shooters’ performance.

Highlights

Shooters showed better acuity skills than non‐athletes.

Shooting activity seems to improve visual acuity skills, binocular visual time and eye–hand coordination in non‐elite shooters, and accommodation and eye–hand coordination in elite shooters immediately after the competition simulation.

Elite shooters employ different visual strategies or skills to non‐elite shooters.

Non‐dominant eye occlusion may benefit binocular vision recovery by inhibiting aiming action and the use of accommodative flexibility could be related to the QE during the shot.
Centriole and PCM cooperatively recruit CEP192 to spindle poles to promote bipolar spindle assembly
Authors: Chinen Takumi , Yamazaki Kaho , Hashimoto Kaho , Fujii Ken , Watanabe Koki , Takeda Yutaka , Yamamoto Shohei , Nozaki Yuka , Tsuchiya Yuki , Takao Daisuke , Kitagawa Daiju
Published: January 2021

The pericentriolar material (PCM) that accumulates around the centriole expands during mitosis and nucleates microtubules. Here, we show the cooperative roles of the centriole and PCM scaffold proteins, pericentrin and CDK5RAP2, in the recruitment of CEP192 to spindle poles during mitosis. Systematic depletion of PCM proteins revealed that CEP192, but not pericentrin and/or CDK5RAP2, was crucial for bipolar spindle assembly in HeLa, RPE1, and A549 cells with centrioles. Upon double depletion of pericentrin and CDK5RAP2, CEP192 that remained at centriole walls was sufficient for bipolar spindle formation. In contrast, through centriole removal, we found that pericentrin and CDK5RAP2 recruited CEP192 at the acentriolar spindle pole and facilitated bipolar spindle formation in mitotic cells with one centrosome. Furthermore, the perturbation of PLK1, a critical kinase for PCM assembly, efficiently suppressed bipolar spindle formation in mitotic cells with one centrosome. Overall, these data suggest that the centriole and PCM scaffold proteins cooperatively recruit CEP192 to spindle poles and facilitate bipolar spindle formation.
Induction of spontaneous human neocentromere formation and long-term maturation
Authors: Murillo-Pineda Marina , Valente Luis P. , Dumont Marie , Mata João F. , Fachinetti Daniele , Jansen Lars E.T.
Published: January 2021

Human centromeres form primarily on α-satellite DNA but sporadically arise de novo at naive ectopic loci, creating neocentromeres. Centromere inheritance is driven primarily by chromatin containing the histone H3 variant CENP-A. Here, we report a chromosome engineering system for neocentromere formation in human cells and characterize the first experimentally induced human neocentromere at a naive locus. The spontaneously formed neocentromere spans a gene-poor 100-kb domain enriched in histone H3 lysine 9 trimethylated (H3K9me3). Long-read sequencing revealed this neocentromere was formed by purely epigenetic means and assembly of a functional kinetochore correlated with CENP-A seeding, eviction of H3K9me3 and local accumulation of mitotic cohesin and RNA polymerase II. At formation, the young neocentromere showed markedly reduced chromosomal passenger complex (CPC) occupancy and poor sister chromatin cohesion. However, long-term tracking revealed increased CPC assembly and low-level transcription providing evidence for centromere maturation over time.
Transmembrane phospholipid translocation mediated by Atg9 is involved in autophagosome formation
Authors: Orii Minami , Tsuji Takuma , Ogasawara Yuta , Fujimoto Toyoshi
Published: January 2021

The mechanism of isolation membrane formation in autophagy is receiving intensive study. We recently found that Atg9 translocates phospholipids across liposomal membranes and proposed that this functionality plays an essential role in the expansion of isolation membranes. The distribution of phosphatidylinositol 3-phosphate in both leaflets of yeast autophagosomal membranes supports this proposal, but if Atg9-mediated lipid transport is crucial, symmetrical distribution in autophagosomes should be found broadly for other phospholipids. To test this idea, we analyzed the distributions of phosphatidylcholine, phosphatidylserine, and phosphatidylinositol 4-phosphate by freeze-fracture electron microscopy. We found that all these phospholipids are distributed with comparable densities in the two leaflets of autophagosomes and autophagic bodies. Moreover, de novo–synthesized phosphatidylcholine is incorporated into autophagosomes preferentially and shows symmetrical distribution in autophagosomes within 30 min after synthesis, whereas this symmetrical distribution is compromised in yeast expressing an Atg9 mutant. These results indicate that transbilayer phospholipid movement that is mediated by Atg9 is involved in the biogenesis of autophagosomes.
Easy and robust micropatterning using fibrinogen anchors
Authors: Latour Simon , McGuigan Alison P.
Published: January 2021

Micropatterning is a process to precisely deposit molecules, typically proteins, onto a substrate of choice with micrometer resolution. Watson et al. (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202009063) describe an innovative yet accessible strategy to enable the reproducible micropatterning of virtually any protein while maintaining its biological activity.
A robust platform for expansion and genome editing of primary human natural killer cells
Authors: Huang Rih-Sheng , Lai Min-Chi , Shih Hsin-An , Lin Steven
Published: January 2021

Genome editing is a powerful technique for delineating complex signaling circuitry and enhancing the functionality of immune cells for immunotherapy. Natural killer (NK) cells are potent immune effectors against cell malignancy, but they are challenging to modify genetically by conventional methods due to the toxicity of DNA when introduced into cells coupled with limited transfection and transduction efficiency. Here, we describe an integrated platform that streamlines feeder-free ex vivo expansion of cryopreserved primary human NK cells and nonviral genome editing by the nucleofection of CRISPR-Cas9 ribonucleoproteins (Cas9 RNPs). The optimized Cas9 nucleofection protocol allows efficient and multiplex gene knockout in NK cells while preserving high cell viability and negligible off-target effects. Cointroduction of a DNA template also enables in-frame gene knock-in of an HA affinity tag and a gfp reporter across multiple loci. This work demonstrates the advantages and flexibility of working with cryopreserved NK cells as potential off-the-shelf engineered therapeutic agents.
Distinct lipid bilayer compositions have general and protein-specific effects on K+ channel function
Authors: Winterstein Laura-Marie , Kukovetz Kerri , Hansen Ulf-Peter , Schroeder Indra , Van Etten James L. , Moroni Anna , Thiel Gerhard , Rauh Oliver
Published: January 2021

It has become increasingly apparent that the lipid composition of cell membranes affects the function of transmembrane proteins such as ion channels. Here, we leverage the structural and functional diversity of small viral K+ channels to systematically examine the impact of bilayer composition on the pore module of single K+ channels. In vitro–synthesized channels were reconstituted into phosphatidylcholine bilayers ± cholesterol or anionic phospholipids (aPLs). Single-channel recordings revealed that a saturating concentration of 30% cholesterol had only minor and protein-specific effects on unitary conductance and gating. This indicates that channels have effective strategies for avoiding structural impacts of hydrophobic mismatches between proteins and the surrounding bilayer. In all seven channels tested, aPLs augmented the unitary conductance, suggesting that this is a general effect of negatively charged phospholipids on channel function. For one channel, we determined an effective half-maximal concentration of 15% phosphatidylserine, a value within the physiological range of aPL concentrations. The different sensitivity of two channel proteins to aPLs could be explained by the presence/absence of cationic amino acids at the interface between the lipid headgroups and the transmembrane domains. aPLs also affected gating in some channels, indicating that conductance and gating are uncoupled phenomena and that the impact of aPLs on gating is protein specific. In two channels, the latter can be explained by the altered orientation of the pore-lining transmembrane helix that prevents flipping of a phenylalanine side chain into the ion permeation pathway for long channel closings. Experiments with asymmetrical bilayers showed that this effect is leaflet specific and most effective in the inner leaflet, in which aPLs are normally present in plasma membranes. The data underscore a general positive effect of aPLs on the conductance of K+ channels and a potential interaction of their negative headgroup with cationic amino acids in their vicinity.
Evidence for S2 flexibility by direct visualization of quantum dot–labeled myosin heads and rods within smooth muscle myosin filaments moving on actin in vitro
Authors: Brizendine Richard K. , Anuganti Murali , Cremo Christine R.
Published: January 2021

Myosins in muscle assemble into filaments by interactions between the C-terminal light meromyosin (LMM) subdomains of the coiled-coil rod domain. The two head domains are connected to LMM by the subfragment-2 (S2) subdomain of the rod. Our mixed kinetic model predicts that the flexibility and length of S2 that can be pulled away from the filament affects the maximum distance working heads can move a filament unimpeded by actin-attached heads. It also suggests that it should be possible to observe a head remain stationary relative to the filament backbone while bound to actin (dwell), followed immediately by a measurable jump upon detachment to regain the backbone trajectory. We tested these predictions by observing filaments moving along actin at varying ATP using TIRF microscopy. We simultaneously tracked two different color quantum dots (QDs), one attached to a regulatory light chain on the lever arm and the other attached to an LMM in the filament backbone. We identified events (dwells followed by jumps) by comparing the trajectories of the QDs. The average dwell times were consistent with known kinetics of the actomyosin system, and the distribution of the waiting time between observed events was consistent with a Poisson process and the expected ATPase rate. Geometric constraints suggest a maximum of ∼26 nm of S2 can be unzipped from the filament, presumably involving disruption in the coiled-coil S2, a result consistent with observations by others of S2 protruding from the filament in muscle. We propose that sufficient force is available from the working heads in the filament to overcome the stiffness imposed by filament-S2 interactions.
Understanding Ca2+ alternans
Authors: Short Ben
Published: January 2021

JGP study reveals that insufficient reuptake of calcium into the sarcoplasmic reticulum underlies arrhythmogenic variations in cardiac calcium transients.
Spectrum of the most powerful series–parallel combination of identical cells
Authors: Hong Seok-In
Published: January 2021

For a given total number of identical cells with internal resistance, we inquire the series–parallel combination of the cells that yields the maximum current through a load resistor linked to the combination. The aspect ratio or shape factor (number of parallel strings/number of serial cells in each string) of cell combination for the maximum load current depends on the resistance ratio (internal resistance/load resistance). Here we provide a systematic, algebraically simple and efficient way to find the (discrete) ‘spectrum’ of the shape factor for the maximum load current as a piecewise-defined function of resistance ratio. In particular, we can get the spectrum by computer programming even when the total number of series–parallel combinations is large as in the case of the electric eel. Furthermore, using the spectrum, we obtain the maximum load current as a piecewise-defined function of resistance ratio. All taken together, this article would be beneficial to university teachers and students because (i) it provides them with pedagogically useful information on the series–parallel combination of identical cells, (ii) its whole process is algebraically easy enough to understand, and (iii) it gives them a good example of using a computer programming in physics education. In addition, it is also of practical importance as the scheme introduced herein can be applied to electric vehicles whose batteries have the pack-module-cell structure.
A silicone based piezoelectric and electromagnetic hybrid vibration energy harvester
Authors: Ali Tashfeen , Khan Farid Ullah
Published: January 2021

This paper describes the investigation of a novel low-cost silicone-based hybrid vibration energy harvester (SHVEH) for converting machine vibrations into useful electrical power for wireless sensor nodes. Due to a novel fabrication technique, the harvester has the benefit of incorporating two transduction mechanisms (electromagnetic and piezoelectric) into a single silicone housing for improved output power. In the devised fabrication technique, water-soluble tablets are used to develop a cavity inside the silicone structure for an embedded magnet to vibrate in. The developed device was characterized inside the lab at different acceleration levels. The SHVEH was found to be capable of delivering a combined output power of 1.12 mW and a power density of 52 µW cm−3. The SHVEH was able to deliver maximum open circuit voltages of 3 V and 28 mV AC via the piezoelectric and electromagnetic portions, respectively, at a resonant frequency of 110 Hz. Furthermore, after connecting the SHVEH to rectifier circuitry, the DC voltage levels obtained were 3.5 V and 35 mV from the piezoelectric and electromagnetic portions, respectively.
Etch-less microfabrication of structured TiO2 implant coatings on bulk titanium grade 23 by direct lithographic anodic oxidation
Authors: Doll P W , Ahrens R , Guber A E
Published: January 2021

Within this work, we demonstrate a method for the etch-less, additive microfabrication of TiO2 thin film layers on top of the medical implant material titanium grade 23. A combination of common UV-lithographic microfabrication and a subsequent anodic oxidation process allows the direct additive fabrication of microstructured oxide layers on top of the bulk base material without the use of any additional preparation or etching step. Titanium grade 23 samples were firstly prepared by grinding and polishing to achieve an adequate surface finish for UV lithography. Photoresist was applied to the samples and lithographically structured using line patterns with lateral sizes ranging from 1.5 up to 50 µm. The samples were then anodically oxidized within a H2SO4 containing electrolyte and the resist patterns could successfully be copied into the resulting oxide layers. The presented method allows cost-effective and fast microfabrication of structured oxide thin film layers while protecting the underlying bulk material from hazardous etching media, often containing hydrofluoric acid, enabling novel implant coating designs and fabrication concepts for future works.
Enhancing discrete-modulated continuous-variable measurement-device-independent quantum key distribution via quantum catalysis
Authors: Ye Wei , Guo Ying , Zhang Huan , Zhong Hai , Mao Yun , Hu Liyun
Published: January 2021

Discrete modulation can make up for the shortage of transmission distance in measurement-device-independent continuous-variable quantum key distribution (MDI-CVQKD), providing a unique advantage against all side-channel attacks but also creating a challenge for further performance improvement. Here we suggest a quantum catalysis (QC) approach for enhancing the performance of the discrete-modulated (DM) MDI-CVQKD in terms of the achievable secret key rate and lengthening the maximal transmission distance. The numerical simulation results show that the QC-based MDI-CVQKD with discrete modulation, involving a zero-photon catalysis (ZPC) operation, can not only obtain a higher secret key rate than the original DM protocol, but also contribute to a reasonable increase of the corresponding optimal variance. As for the extreme asymmetric and symmetric cases, the secret key rate and maximal transmission distance of the ZPC-involved DM MDI-CVQKD system can be further improved under the same parameters. This approach enables the system to tolerate lower reconciliation efficiency, which may provide excellent potential for practical implementations with state-of-art technology.
A hybrid modeling framework for the investigation of surface roughening of polymers during oxygen plasma etching
Authors: Memos George , Lidorikis Elefterios , Gogolides Evangelos , Kokkoris George
Published: January 2021

Oxygen and oxygen-containing plasmas offer great potential for the surface functionalization of polymeric substrates: thermal reactive neutral species are combined with high energy ions to alter both the micro/nanomorphology and composition of polymeric surfaces in a dry process. Although plasma processing is an attractive option for polymer surface modification, plasma–surface interactions are complex and the process design is usually based on a trial-and-error procedure. Toward a comprehensive process design, a hybrid modeling framework, addressing both effects of plasmas on polymeric surfaces, is developed and applied to an investigation of the oxygen-plasma-induced surface roughening of poly(methyl methacrylate). A kinetic Monte Carlo surface model, considering the synergy of neutral species and ions, is used for the calculation of the local etching rate. The novel element of the model is that it takes into account the surface morphology through the calculation of the trajectories of the species joining the surface reactions. The local etching rate is utilized by a profile evolution module based on the level set method to predict the surface roughness evolution. A method for tracking the local variables of the evolving surface profile (e.g. surface coverage), treating a fundamental weakness of the level set method, is proposed and used to effectively reduce the computational time. The results of the framework are validated by comparison to a theoretical model. The prediction of roughness evolution is consistent with measurements vs time and at different operating conditions. The potential of the framework to additionally handle the chemical composition (oxidation) of the surface is demonstrated, enabling the study of the wetting behavior of plasma-etched polymeric surfaces.
Analysis of the physical and photoelectrochemical properties of c-Si(p)/a-SiC:H(p) photocathodes for solar water splitting
Authors: Carmen Mejia María del , Sánchez Luis Francisco , Kurniawan Mario , Eggert Lara , Tejada Alvaro , Camargo Magali , Grieseler Rolf , Rumiche Francisco , Díaz Isabel , Bund Andreas , Guerra Jorge Andrés
Published: January 2021

The photoelectrochemical (PEC) properties of sputtered aluminum doped hydrogenated amorphous silicon carbide thin films grown on p-type crystalline silicon substrates were investigated in 1 M

H

2

S
O

4

solution under chopped light illumination. Optical and structural properties of the top absorber layer were systematically assessed after post-deposition isochronical annealing treatments. Samples exhibited a noticeable improvement of the opto-electronic properties after thermal treatments. In addition, an abrupt enhancement of the photocurrent was observed reaching a saturation value of 17 mA cm−2 at −1.75 V vs. Ag/AgCl (3.5 M KCl). In this research we propose that this enhancement effect is associated to a charge transfer kinetic mechanism influenced by surface states and the p-type substrate. The latter most likely due to the space charge region extending beyond the absorber layer reaching the substrate. Current density-potential and electrochemical impedance spectroscopy measurements in dark revealed a reduction of the

S
i
O

2

native layer at cathodic potentials higher than −1 V vs. Ag/AgCl (3.5 M KCl), which contributes to the high charge transfer kinetic of the system. We believe that these results will contribute to understand the substrate influence in the PEC performance of top absorber layers in multilayer structures for solar water splitting.
Sub-picosecond exchange–relaxation in the compensated ferrimagnet Mn2Ru
x
Ga
Authors: Bonfiglio G , Rode K , Atcheson G Y P , Stamenov P , Coey J M D , Kimel A V , Rasing Th , Kirilyuk A
Published: January 2021

We study the demagnetization dynamics of the fully compensated half-metallic ferrimagnet Mn2Ru
x
Ga. While the two antiferromagnetically coupled sublattices are both composed of manganese, they exhibit different temperature dependencies due to their differing local environments. The sublattice magnetization dynamics triggered by femtosecond laser pulses are studied to reveal the roles played by the spin and intersublattice exchange. We find a two-step demagnetization process, similar to the well-established case of Gd(FeCo)3, where on a 5 ps timescale the two Mn-sublattices seem to have different demagnetization rates. The behaviour is analysed using a four-temperature model, assigning different temperatures to the two manganese spin baths. Even in this strongly exchange-coupled system, the two spin reservoirs have considerably different behaviour. The half-metallic nature and strong exchange coupling of Mn2Ru
x
Ga lead to spin angular momentum conservation at much shorter time scales than found for Gd(FeCo)3 which suggests that low-power, sub-picosecond switching of the net moment of Mn2Ru
x
Ga is possible.
Spin induced exchange bias and lattice modulation in Nd1−x
Eu
x
CrO3
Authors: Gupta Pragya , Pal D
Published: January 2021

We report the evolution of coupled phonons and exchange bias (EB) in perovskite-type Nd1−x
Eu
x
CrO3 (x = 0.0, 0.05, and 0.10) samples by means of temperature-dependent Raman spectroscopy and dc magnetization measurements. We observed a non-monotonic behavior of the EB field around the temperature T
*, which lies between the antiferromagnetic ordering temperature (T
N) and spin-reorientation transition temperature (T
SR). The temperature dependence of phonon modes related to antistretching and bending of CrO6 octahedra and Nd3+/Eu3+ ion vibration below T
N confirms the strong spin–phonon coupling. The T
* found from the non-monotonicity of the EB is imprinted with the additional anomaly observed in the low-temperature spin–phonon behavior. The phonon modes and phonon anomaly are also verified using the density functional theory-based calculations.
Exchange interactions in ɛ-Fe2O3: GGA + U calculations
Authors: Knížek K , Novák P , Jirák Z
Published: January 2021

We have studied the origin of magnetic interaction in ɛ-Fe2O3 by ab-initio electronic structure calculations. The exchange integrals of the Heisenberg Hamiltonian have been calculated using the methods based on the density functional theory (DFT) employing generalized gradient approximation (GGA) with orbital dependent potential extension for 3d electrons of Fe (GGA + U method). The calculations confirm the ground antiferromagnetic (AFM) state with two Fe3+ sublattices oriented up (Fe2 and Fe3) and two Fe3+ sublattices oriented down (Fe1 and Fe4). The calculated exchange integrals, including also the intra-sublattice ones, are all of AFM type. Their strength weighted by the number of neighbors is larger between the Fe sublattices with opposite spins than between the sublattices with equal spin directions. The notable exception is a strong exchange integral between the neighboring tetrahedrally-coordinated sites within the Fe4 sublattice, which effectively decreases the molecular field imposed on Fe4 sites by neighboring sites of other sublattices, namely the antiparallelly oriented Fe2 and Fe3. For this reason, the ordered magnetic moment of Fe4 exhibits the fastest decrease with increasing temperature among the sublattices, leading to an uncompensated AFM arrangement in ɛ-Fe2O3. Considering the competition of the inter- and intra-sublattice exchange integrals and applying symmetry arguments, we infer that the collinear AFM ground state of ɛ-Fe2O3 is prone to an intrinsic canting within the sublattices, retaining at the same time the magnetic group symmetry Pna′21′.
Flow status identification based on multiple slow feature analysis of gas–liquid two-phase flow in horizontal pipes
Authors: Dong Feng , Li Linghan , Zhang Shumei
Published: January 2021

A gas–liquid two-phase flow is a highly complex and random process with complicated and variable flow statuses. The status identification of two-phase flows focuses on the situation of flow processes over specific time periods, as reflected by flow regimes, phase holdup, flow velocity, and other parameters. Aiming to discover how to obtain flow status information and identify the flow statuses of gas–liquid two-phase flows in horizontal pipes, a meticulous identification method based on multiple slow feature analysis combined with Bayesian inference is proposed, with concurrent monitoring of steady states and process dynamics. In this method, representational models for different typical flow regimes are established to describe both the steady states and temporal distributions. On this basis, by monitoring statistics and developing a Bayesian inference-based index, the current flow status can be identified online. Besides status identification, process dynamics are monitored to detect the dynamic characteristics of the current process with meaningful physical interpretation and deep process understanding. The application of this method to typical flow regimes and the status of transitions from bubble flow to slug flow demonstrates the feasibility and efficacy of the proposed method.
Error analysis and reflection correction for radiation temperature measurements at high background temperatures
Authors: Gao Shan , Zhao Chunhui , Chen Liwei , Jiang Jing , Yu Peifeng , Zhang Zezhan , Wang Chao
Published: January 2021

Advances in science and technology have increased the demand for greater temperature measurement accuracy. Radiation thermometry is a mature technology that is applicable to various industrial fields. In special environments (e.g. a high ambient temperature), background radiation reflected by the target surface is superimposed with the radiation from the target itself, which affects the measured radiation temperature. In this study, different radiation thermometry methods were evaluated. The errors of single-spectral, colorimetric, and multispectral temperature measurements of targets in a high-temperature environment have been discussed. Based on this, we propose a multi-wavelength temperature measurement method with reflection correction to reduce the impact of high-temperature environment. Experiments show that this method can reduce the uncertainty in the multispectral temperature measurement from 4.16% to 0.26% under the experimental conditions.
An encoder signal-based approach for low-speed planetary gearbox fault diagnosis
Authors: Ou Shudong , Zhao Ming , Zhou Tao , Guo Dong
Published: January 2021

Low-speed rotating machines are extensively used in heavy industry. Among those, the planetary gearbox is a pivotal component with a high power–weight ratio and large loadbearing capacity, which inevitably fail due to the tough working conditions. The fault signature in such conditions is rather weak due to the complex planetary structure and the low rotating speed. Hence, the diagnosis of planetary gearbox problems in low-speed working conditions is considered as a bottleneck issue. In view of this, a rotary encoder signal, instead of conventional vibration, is initially applied to capture the fault-related information from the low-speed planetary gearbox. Then, a periodic group sparse-robust principal component analysis (PGS-RPCA) model with adaptive parameter programming, called adaptive PGS-RPCA (APGS-RPCA) is presented to extract the weak fault transient immersed in harmonic interferences and heavy noise. Finally, the effectiveness of the presented APGS-RPCA approach is verified via an experimental encoder signal at a very low input frequency. The diagnostic results show that the presented approach is superior to the conventional approach, and it may provide a promising solution for health monitoring of low-speed rotating machinery.
Hyaluronic acid functionalized biodegradable mesoporous silica nanocomposites for efficient photothermal and chemotherapy in breast cancer
Authors: Zhan Wenhua , Li Hanrui , Guo Yingying , Yang Lu , Pang Liaojun , Zhang Chaolin
Published: January 2021

Chemotherapy is one of conventional treatment methods for breast cancer, but drug toxicity and side effects have severely limited its clinical applications. Photothermal therapy has emerged as a promising method that, upon combination with chemotherapy, can better treat breast cancer. In this context, a biodegradable mesoporous silica nanoparticle (bMSN NPs) system was developed for loading doxorubicin (DOX) and IR780, to be potentially applied in the treatment of breast cancer. IR780 is encapsulated in the pores of bMSN NPs by hydrophobic adsorption, while DOX is adsorbed on the surface of the bMSN NPs by hyaluronic acid electrostatically, to form the bMID NPs. Transmission electron microscopy, fluorescence spectrum and UV absorption spectrum are used to prove the successful encapsulation of IR780 and the loading of DOX. In vitro experiments have shown bMID NPs present an excellent therapeutic effect on breast cancer cells. In vivo fluorescence imaging results have indicated that bMID NPs can accumulate in tumor sites gradually and achieve in vivo long-term circulation and continuous drug release. Furthermore, bMID NPs have provided obvious antitumor effects in breast cancer mouse models, thus evolving as an efficient platform for breast cancer therapy.
Wurtzite phase control for self-assisted GaAs nanowires grown by molecular beam epitaxy
Authors: Dursap T , Vettori M , Botella C , Regreny P , Blanchard N , Gendry M , Chauvin N , Bugnet M , Danescu A , Penuelas J
Published: January 2021

The accurate control of the crystal phase in III–V semiconductor nanowires (NWs) is an important milestone for device applications. Although cubic zinc-blende (ZB) GaAs is a well-established material in microelectronics, the controlled growth of hexagonal wurtzite (WZ) GaAs has thus far not been achieved successfully. Specifically, the prospect of growing defect-free and gold catalyst-free wurtzite GaAs would pave the way towards integration on silicon substrate and new device applications. In this article, we present a method to select and maintain the WZ crystal phase in self-assisted NWs by molecular beam epitaxy. By choosing a specific regime where the NW growth process is a self-regulated system, the main experimental parameter to select the ZB or WZ phase is the V/III flux ratio. Using an analytical growth model, we show that the V/III flux ratio can be finely tuned by changing the As flux, thus driving the system toward a stationary regime where the wetting angle of the Ga droplet can be maintained in the range of values allowing the formation of pure WZ phase. The analysis of the in situ reflection high energy electron diffraction evolution, combined with high-resolution scanning transmission electron microscopy (TEM), dark field TEM, and photoluminescence all confirm the control of an extended pure WZ segment, more than a micrometer long, obtained by molecular beam epitaxy growth of self- assisted GaAs NWs with a V/III flux ratio of 4.0. This successful controlled growth of WZ GaAs suggests potential benefits for electronics and opto-electronics applications.
Growth of long III-As NWs by hydride vapor phase epitaxy
Authors: Gil Evelyne , Andre Yamina
Published: January 2021

In this review paper, we focus on the contribution of hydride vapor phase epitaxy (HVPE) to the growth of III-As nanowires (NWs). HVPE is the third epitaxial technique involving gaseous precursors together with molecular beam epitaxy (MBE) and metal-organic VPE (MOVPE) to grow III–V semiconductor compounds. Although a pioneer in the growth of III–V epilayers, HVPE arrived on the scene of NW growth the very last. Yet, HVPE brought different and interesting insights to the topic since HVPE is a very reactive growth system, exhibiting fast growth property, while growth is governed by the temperature-dependent kinetics of surface mechanisms. After a brief review of the specific attributes of HVPE growth, we first feature the innovative polytypism-free crystalline quality of cubic GaAs NWs grown by Au-assisted vapor–liquid–solid (VLS) epitaxy, on exceptional length and for radii down to 6 nm. We then move to the integration of III–V NWs with silicon. Special emphasis is placed on the nucleation issue experienced by both Au-assisted VLS MOVPE and HVPE, and a model demonstrates that the presence of Si atoms in the liquid droplets suppresses nucleation of NWs unless a high Ga concentation is reached in the catalyst droplet. The second known issue is the amphoteric behavior of Si when it is used as doping element for GaAs. On the basis of compared MBE and HVPE experimental data, a model puts forward the role of the As concentration in the liquid Au–Ga–As–Si droplets to yield p-type (low As content) or n-type (high As content) GaAs:Si NWs. We finally describe how self-catalysed VLS growth and condensation growth are implemented by HVPE for the growth of GaAs and InAs NWs on Si.
Three-phase composites of NiFe2O4/Ni@C nanoparticles derived from metal-organic frameworks as electrocatalysts for the oxygen evolution reaction
Authors: Wei Xuedong , Liu Nan , Chen Weifeng , Qiao Shuangyan , Chen Yuanzhen
Published: January 2021

Composite electrocatalysts of carbon and metals or metal compounds with homogeneous active sites can be obtained through the carbonization of metal organic framework (MOF) materials under inert atmosphere. In this work, a three-phase composite electrocatalysts NiFe2O4/Ni@C were prepared via pyrolysis from self-assembled MOF nanosheets aggregates. The excellent electrocatalytic activity of the obtained electrocatalysts with various Ni:Fe ratios is demonstrated. Especially, the NiFe2O4/Ni@C sample with the mole ratio of Ni:Fe = 1:1 can use the overpotential (η) of 330 and 423 mV to drive 10 and 50 mA cm−2 respectively. After 80 000 s/22 h, the current density could retained 90% of the initial current density. The excellent activity and stability of the electrocatalysts are attributed to nickel and iron ions with uniform dispersion at atomic level in the NiFe2O4 phase and the synergistic effect of nickel and NiFe2O4 nanoparticles with amorphous carbon atoms or nanoparticles around.
Mn2+ ions incorporated into ZnS
x
Se1−x
colloidal quantum dots: controlling size and composition of nanoalloys and regulating magnetic dipolar interactions
Authors: Sevim Ünlütürk Seçil , Akdoğan Yaşar , Özçelik Serdar
Published: January 2021

A facile synthesis method is introduced how to prepare magnetically active ultraviolet emitting manganese ions incorporated into ZnS
x
Se1−x
colloidal quantum dot (nanoalloy) at 110 °C in aqueous solutions. The reaction time is the main factor to control the hydrodynamic size from 3 to 10 nm and the precursor ratio is significant to tune the alloy composition. ZnS shell layer on the ZnS
x
Se1−x
core was grown to passivate environmental effects. The nanoalloy has ultraviolet emission at 380 nm having a lifetime of 80 ns and 7% quantum yield. The incorporation of Mn2+ ions into the nanoalloys induced magnetic activity but did not modify the structure and photophysical properties of the nanoalloys. Colloidal and powdery samples were prepared and analyzed by electron paramagnetic resonance (EPR) spectroscopy. In the colloidal dispersions, EPR spectra showed hyperfine line splitting regardless of the Mn2+ ion fractions, up to 6%, indicating that Mn2+ ions incorporated into the nanoalloys were isolated. EPR signals of the powdery samples were broadened when the fraction of Mn2+ ions was higher than 0.1%. The EPR spectra were simulated to reveal the locations and interactions of Mn2+ ions. The simulations suggest that the Mn2+ ions are located on the nanoalloy surfaces. These findings infer that the magnetic dipolar interactions are regulated by the initial mole ratio of Mn/Zn and the physical state of the nanoalloys adjusted by preparation methods.
How do I introduce Schrödinger equation during the quantum mechanics course?
Authors: Mart T
Published: January 2021

In this paper I explain how I usually introduce the Schrödinger equation during the quantum mechanics course. My preferred method is the chronological one. Since the Schrödinger equation belongs to a special case of wave equations I start the course with introducing the wave equation. The Schrödinger equation is derived with the help of the two quantum concepts introduced by Max Planck, Einstein, and de Broglie, i.e. the energy of a photon E = ћω and the wavelength of the de Broglie wave λ = h/p. Finally, the difference between the classical wave equation and the quantum Schrödinger one is explained in order to help the students to grasp the meaning of quantum wavefunction

Ψ
(

r

,
t
)

. A comparison of the present method to the approaches given by the authors of quantum mechanics textbooks as well as that of the original Nuffield A level is presented. It is found that the present approach is different from those given by these authors, except by Weinberg or Dicke and Wittke. However, the approach is in line with the original Nuffield A level one.
Reference dosimetry of modulated and dynamic photon beams
Authors: Bouchard Hugo
Published: January 2021

In the late 1980s, a new technique was proposed that would revolutionize radiotherapy. Now referred to as intensity-modulated radiotherapy, it is at the core of state-of-the-art photon beam delivery techniques, such as helical tomotherapy and volumetric modulated arc therapy. Despite over two decades of clinical application, there are still no established guidelines on the calibration of dynamic modulated photon beams. In 2008, the IAEA-AAPM work group on nonstandard photon beam dosimetry published a formalism to support the development of a new generation of protocols applicable to nonstandard beam reference dosimetry (Alfonso et al 2008 Med. Phys.
35 5179–86). The recent IAEA Code of Practice TRS-483 was published as a result of this initiative and addresses exclusively small static beams. But the plan-class specific reference calibration route proposed by Alfonso et al (2008 Med. Phys.
35 5179–86) is a change of paradigm that is yet to be implemented in radiotherapy clinics. The main goals of this paper are to provide a literature review on the dosimetry of nonstandard photon beams, including dynamic deliveries, and to discuss anticipated benefits and challenges in a future implementation of the IAEA-AAPM formalism on dynamic photon beams.
Inverse treatment planning for an electronic brachytherapy system delivering anisotropic radiation therapy
Authors: Badali Daniel S , Vainer Yonatan , Ellenor Christopher W , Mitchell Christopher R , Fishman Kalman , Soro Nicolas , Price Russ , Funk Tobias
Published: January 2021

An inverse radiation treatment planning algorithm for Sensus Healthcare’s SculpturaTM electronic brachytherapy system has been designed. The algorithm makes use of simulated annealing to optimize the conformation number (CN) of the treatment plan. The highly anisotropic dose distributions produced by the SculpturaTM x-ray source empower the inverse treatment planning algorithm to achieve highly conformal treatment plans for a wide range of prescribed planning target volumes. Over a set of 10 datasets the algorithm achieved an average CN of 0.79 ± 0.08 and an average gamma passing rate of 0.90 ± 0.10 at 5%/5 mm. A regularization term that encouraged short treatment plans was used, and it was found that the total treatment time could be reduced by 20% with only a nominal reduction in the CN and gamma passing rate. It was also found that downsampling the voxelized volume (from 3203 to 643 voxels) prior to optimization resulted in a 150× speedup in the optimization time (from 2 + minutes to < 1 s) without affecting the quality of the treatment plan.
Video-based sleep detection using ocular signals under the standard conditions of the maintenance of wakefulness test in patients with sleep disorders
Authors: Kratzel Lucas , Glos Martin , Veauthier Christian , Rekow Sven , François Clémentine , Fietze Ingo , Penzel Thomas
Published: January 2021

Objective. Excessive sleepiness is a physiological reaction to sleep deficiency but can also be caused by underlying medical conditions. Detecting sleep is essential in preventing accidents and for medical diagnostics. Polysomnography (PSG) is considered the gold standard for the detection of sleep. More convenient video-based methods for detecting sleepiness have recently emerged. Approach. The possibility of detecting sleep using video-based ocular signals will be assessed using PSG for reference. Ocular signals and EEG are recorded in parallel under the conditions of the maintenance of wakefulness test (MWT) in 30 patients with sleep disorders. Main results. In detecting sleep, the ocular signal percentage of eyelid closure (PERCLOS) is superior to other ocular signals, resulting in an area under the curve of 0.88. Using a PERCLOS cutoff value of 0.76, sleep is correctly detected with a sensitivity of 89%, a specificity of 76%, the sleep latency is moderately correlated to the reference (rho = 0.66, p < 0.05) and the 95% confidence interval is ±21.1 min. Significance. Ocular signals can facilitate the detection of sleep under the conditions of the MWT but sleep detection should not solely rely on ocular signals. If PSG recordings are not practicable or if a signal is needed that responds relatively early in the wake/sleep transition, the use of PERCLOS for the detection of sleep is reasonable.
Phase relation between rotating phase locked (2, 1) and (3, 1) tearing modes in ASDEX Upgrade
Authors: Gude A , Maraschek M , Igochine V , Sieglin B , Willensdorfer M , Zohm H
Published: January 2021

Tearing modes are a major concern for large tokamak devices. Therefore their detection and characterization is of importance for timely countermeasures to avoid significant impact on the discharge or at least prevent possible machine damage. In case of phase-locked tearing modes, the poloidal variation of induced magnetic field fluctuation depends on the amplitudes of and the phase difference between the individual modes. This affects mode detection and identification when not considered appropriately. The phase between phase-locked (2, 1) and (3, 1) tearing modes in ASDEX Upgrade has been determined from local electron temperature and magnetic measurements independently. It is shown that the modes can be in phase at any poloidal position starting from the low field side plasma midplane over the plasma top to the high field side midplane. This observation invalidates the widespread assumption that phase-locked tearing modes are in phase near the low field side midplane. Dependence of the in-phase position on both, the plasma pressure and the plasma rotation velocity, is observed.