bluuebunny/crossref_metadata_2025 huggingface dataset:
Photothermal therapy using graphene quantum dots
Authors: Dar Mohammad Suhaan , Tabish Tanveer A. , Thorat Nanasaheb D. , Swati G. , Sahu Niroj Kumar
Published: August 2023

The rapid development of powerful anti-oncology medicines have been possible because of advances in nanomedicine. Photothermal therapy (PTT) is a type of treatment wherein nanomaterials absorb the laser energy and convert it into localized heat, thereby causing apoptosis and tumor eradication. PTT is more precise, less hazardous, and easy-to-control in comparison to other interventions such as chemotherapy, photodynamic therapy, and radiation therapy. Over the past decade, various nanomaterials for PTT applications have been reviewed; however, a comprehensive study of graphene quantum dots (GQDs) has been scantly reported. GQDs have received huge attention in healthcare technologies owing to their various excellent properties, such as high water solubility, chemical stability, good biocompatibility, and low toxicity. Motivated by the fascinating scientific discoveries and promising contributions of GQDs to the field of biomedicine, we present a comprehensive overview of recent progress in GQDs for PTT. This review summarizes the properties and synthesis strategies of GQDs including top-down and bottom-up approaches followed by their applications in PTT (alone and in combination with other treatment modalities such as chemotherapy, photodynamic therapy, immunotherapy, and radiotherapy). Furthermore, we also focus on the systematic study of in vitro and in vivo toxicities of GQDs triggered by PTT. Moreover, an overview of PTT along with the synergetic application used with GQDs for tumor eradication are discussed in detail. Finally, directions, possibilities, and limitations are described to encourage more research, which will lead to new treatments and better health care and bring people closer to the peak of human well-being.
Implementation of the meta-GGA exchange-correlation functional in numerical atomic orbital basis: With systematic testing on SCAN, rSCAN, and r2SCAN functionals
Authors: Liu Renxi , Zheng Daye , Liang Xinyuan , Ren Xinguo , Chen Mohan , Li Wenfei
Published: August 2023

Kohn–Sham density functional theory (DFT) is nowadays widely used for electronic structure theory simulations, and the accuracy and efficiency of DFT rely on approximations of the exchange-correlation functional. By including the kinetic energy density τ, the meta-generalized-gradient approximation (meta-GGA) family of functionals achieves better accuracy and flexibility while retaining the efficiency of semi-local functionals. For example, the strongly constrained and appropriately normed (SCAN) meta-GGA functional has been proven to yield accurate results for solid and molecular systems. We implement meta-GGA functionals with both numerical atomic orbitals and plane wave bases in the ABACUS package. Apart from the exchange-correlation potential, we also discuss the evaluation of force and stress. To validate our implementation, we perform finite-difference tests and convergence tests with the SCAN, rSCAN, and r2SCAN meta-GGA functionals. We further test water hexamers, weakly interacting molecules from the S22 dataset, as well as 13 semiconductors using the three functionals. The results show satisfactory agreement with previous calculations and available experimental values.
Flexural-gravity wave interaction with multiple vertical cylinders of arbitrary cross section frozen in an ice sheet
Authors: Shi Y. Y. , Li Z. F. , Wu G. X.
Published: August 2023

The interaction problem of flexural-gravity wave with multiple vertical cylinders frozen in an ice sheet on the surface of water with finite water depth is considered. The linearized velocity potential theory is adopted for fluid flow, and the thin elastic plate model is applied for ice sheet deflection. Each cylinder is bottom-mounted, and the shape of its cross section can be arbitrary while remaining constant in the vertical direction. The velocity potential is expanded into an eigenfunction series in the vertical direction, which satisfies the boundary condition on the ice sheet automatically. The horizontal modes, which satisfy the Helmholtz equations, are then transformed into a series of boundary integral equations along the ice sheet edges or the intersection of the ice sheet with the cylinders. The problem is then solved numerically by imposing the ice sheet edge condition together with the impermeable condition on the cylinders. The solution is exact in the sense that the error is only due to numerical discretization and truncation. Computations are first carried out for single and multiple vertical circular cylinders, and good agreements are obtained with the semi-analytical solution. To resolve the difficulty of excessive computation at a large number of cylinders, the effect of the evanescent wave of a cylinder on those at large distance is ignored. This allows for the case of a large number of cylinders in different arrangements to be simulated. Extensive results are provided. Their physics and practical relevance are discussed.
Li–Yorke chaos of linear differential equations in a finite-dimensional space with a weak topology
Authors: Zhang Xu , Jiang Nan , Yang Qigui , Chen Guanrong
Published: August 2023

Li–Yorke chaos of linear differential equations in a finite-dimensional space with a weak topology is introduced. Based on this topology on the Euclidean space, a flow generated from a linear differential equation is proved to be Li–Yorke chaotic under certain conditions, which is in sharp contract to the well-known fact that linear differential equations cannot be chaotic in a finite-dimensional space with a strong topology.
Applied in-plane strain effects on the polarization response of ferroelectric hafnium zirconium oxide thin films
Authors: Ihlefeld Jon F. , Peters Travis , Jaszewski Samantha T. , Mimura Takanori , Aronson Benjamin L. , Trolier-McKinstry Susan
Published: August 2023

The influence of biaxial stress on the maximum and remanent polarizations of 10 nm thick hafnium zirconium oxide thin films in metal–ferroelectric–metal capacitor structures has been quantified. In the as-prepared state with a nominal biaxial tensile strain of 0.20% and no applied extrinsic stress, remanent and maximum polarizations of 7.6 and 13.1 μC/cm2, respectively, were measured using a 2 MV/cm applied electric field. Reducing the intrinsic strain by 0.111% through the application of a compressive uniaxial stress results in a decrease in the remanent and maximum polarizations to 6.8 and 12.2 μC/cm2, respectively. The polarization dependence on strain is nearly linear between these values. The observed variation in polarization with strain is consistent with strain impacting ferroelastic switching whereby in-plane tension increases the fraction of the short polar axis orienting out-of-plane, hence increasing out-of-plane polarization. In contrast, reducing the in-plane strain through compression results in an increase in the fraction of the long non-polar axis orienting out-of-plane, thereby decreasing out-of-plane polarization.
Quantized vortex nucleation in collisions of superfluid nanoscopic helium droplets at zero temperature
Authors: García-Alfonso Ernesto , Ancilotto Francesco , Barranco Manuel , Pi Martí , Halberstadt Nadine
Published: August 2023

We address the collision of two superfluid 4He droplets at non-zero initial relative velocities and impact parameters within the framework of liquid 4He time-dependent density functional theory at zero temperature. Despite the small size of these droplets (1000 He atoms in the merged droplet) imposed by computational limitations, we have found that quantized vortices may be readily nucleated for reasonable collision parameters. At variance with head-on collisions, where only vortex rings are produced, collisions with a non-zero impact parameter produce linear vortices that are nucleated at indentations appearing on the surface of the deformed merged droplet. Whereas for equal-size droplets, vortices are produced in pairs, an odd number of vortices can appear when the colliding droplet sizes are different. In all cases, vortices coexist with surface capillary waves. The possibility for collisions to be at the origin of vortex nucleation in experiments involving very large droplets is discussed. An additional surprising result is the observation of the drops coalescence even for grazing and distal collisions at relative velocities as high as 80 and 40 m/s, respectively, induced by the long-range van der Waals attraction between the droplets.
Rayleigh–Bénard convection of viscoelastic fluids in three-dimension finite cavity
Authors: Zheng Xin , Wang Chao , Peng Xin-Yu , Zhang Shuo , Zhang Hong-Na , Wang Yue , Cai Wei-Hua
Published: August 2023

The Rayleigh–Bénard convection (RBC) with viscoelastic fluids has captured wide attention in the past decades, caused by its ubiquitous uses in the heat transfer process. However, the numerical technique for simulating the viscoelastic fluid flows developed slowly until recent years because of the numerical instability raised by the hyperbolic characteristics of the viscoelastic constitutive equation. In the present work, a novel numerical scheme was developed to simulate the three-dimension (3D) RBC with viscoelastic fluids, where the quasi-linear treatment was applied to the hyperbolic terms of the momentum equation and the viscoelastic constitutive equation. The in-house solver was also optimized in the aspect of time cost. The results show that the critical value of convection onset in 3D is near to that in the two-dimension (2D); however, the flow pattern displays the wave characteristics in the horizontal direction. The viscoelastic kinetic energy budget of oscillating convection in 3D still conforms to the energy transport law of that in 2D [Zheng et al., Phys. Rev. Fluids 8, 023303 (2023)].
Research on the performance of green and environmentally friendly epoxy resin impregnated paper 110 kV current transformer
Authors: Fang Zhao , Yang Xuefeng , Zeng Haiyan , Liu Haiqiong , Zhou Xiang , Zhu Wei , Xia Huaimin
Published: August 2023

As an important high-voltage electrical equipment in the substation, the performance stability of high-voltage current transformers is directly related to the safe operation of the power grid. The insulating medium of the traditional oil-immersed current transformer is an oil-immersed paper structure. When the oil-immersed current transformer malfunctions, it is easy to cause fire and explosion, resulting in very serious consequences. If the transformer with the epoxy resin impregnated paper insulation medium is used, there is no oil and gas inside; thus, it has high reliability, which greatly reduces the risk of fire and explosion. Based on this, considering the application research on the high-voltage current transformers epoxy resin impregnated paper technology, this paper mainly analyzes some precautions for the application of epoxy resin impregnated paper technology to the high-voltage current transformers from three aspects: the research on the insulation performance of the epoxy resin impregnated paper transformers, the research on the mechanical properties, and the research on the relevant experimental methods of the epoxy resin impregnated paper technology application to the high-voltage current transformers.
Bioactive Zn-0.6Cu thin sheet for craniofacial bone repair: In vitro and in vivo evaluations
Authors: Xiao Yong , Zhuang Dongzhou , Chen Fan , Li Tian , Wang Hao , Zhong Yuan , Luo Cheng , Chen Junchen , Yao Wenmin , Chen Weiqiang
Published: August 2023

Millions of craniofacial surgeries are performed annually worldwide, and materials for craniofacial bone repair are widely needed. However, traditionally applied materials, such as titanium and polymethylmethacrylate, have some shortcomings (limited malleability, material-based toxicity, non-biodegradability, lack of bioactivity, etc.). Zinc based biodegradable metals possess superior mechanical properties, biodegradability, and bioactivity, which make them promising candidate materials. Here, we successfully fabricated Zn-0.6Cu thin sheets (thickness ≤0.5 mm, suitable for craniofacial surgery) through combined extrusion and rolling. The in vitro and in vivo performances were generally evaluated and compared to those of a commercially applied pure titanium mesh. The mechanical properties of Zn-0.6Cu sheets were superior to those of clinically used polymethyl methacrylate. They were easy to shape and would not fracture during deformation. The Zn-0.6Cu sheet exhibited a gentle degradation mode, and proper implant-derived Zn improved osteogenic differentiation of rat bone marrow mesenchymal stem cells by up-regulating expression of osteogenesis related genes (alkaline phosphatase, bone morphogenetic protein-2). Thus, it further promoted extracellular matrix mineralization by improving calcium deposition for bone formation. It also improved the expression of angiogenesis-related genes (vascular endothelial growth factor, hypoxia-inducible factor alpha). The Zn-0.6Cu sheet exhibited high osteogenic activity in a cranial defect animal model compared to a non-biodegradable pure titanium mesh. Significant surface degradation occurred after two months in vivo, and degradation products were compatible with surrounding tissues. In general, the Zn-0.6Cu thin sheet seems to be a bioactive material selection for craniofacial bone repair, which might possibly accelerate defect repair and prevent adverse complications.
All-solid-state CW Pr3+:YLF green laser at 522 nm end-pumped by a high-power fiber-coupled 444 nm blue LD module
Authors: Li Fengqin , Chen Jin , Weng Yupeng
Published: August 2023

Continuous wave (CW) green lasers have a lot of important applications in many fields, including holography, interferometry, atom cooling and trapping, and quantum optics, and they are usually achieved by frequency-doubling 1 µm lasers based on the Nd3+ gain media. In this paper, we present an all-solid-state CW green laser with an output wavelength of 522 nm, which was directly attained by employing a Pr3+:YLF crystal pumped with a high-power fiber-coupled blue laser diode (LD) module as the gain medium. Due to the negative thermal lens effect of the Pr3+:YLF crystal, the designed laser resonator had to be lengthened with the increase in the incident pump power. As a result, when a 0.5% doped Pr3+:YLF crystal was employed as the gain medium and the incident pump power was 12 W, the length of the resonator was optimized to 311.3 mm and the maximum output power of 522 nm green laser was up to 886 mW. The obtained conversion efficiency and beam quality M2 were 11.25% and 1.15, respectively. The long-term power stability within 4.5 h was better than ±1.5% at an output power of 700 mW. The obtained watt-level green laser can also be used to generate high power CW deep UV laser for laser processing of silicon and organic materials, inspection, etc.
IgG3 subclass antibodies recognize antigenically drifted influenza viruses and SARS-CoV-2 variants through efficient bivalent binding
Authors: Bolton Marcus J. , Santos Jefferson J. S. , Arevalo Claudia P. , Griesman Trevor , Watson Megan , Li Shuk Hang , Bates Paul , Ramage Holly , Wilson Patrick C. , Hensley Scott E.
Published: August 2023

The constant domains of antibodies are important for effector functions, but less is known about how they can affect binding and neutralization of viruses. Here, we evaluated a panel of human influenza virus monoclonal antibodies (mAbs) expressed as IgG1, IgG2, or IgG3. We found that many influenza virus–specific mAbs have altered binding and neutralization capacity depending on the IgG subclass encoded and that these differences result from unique bivalency capacities of the subclasses. Importantly, subclass differences in antibody binding and neutralization were greatest when the affinity for the target antigen was reduced through antigenic mismatch. We found that antibodies expressed as IgG3 bound and neutralized antigenically drifted influenza viruses more effectively. We obtained similar results using a panel of SARS-CoV-2-specific mAbs and the antigenically advanced B.1.351 and BA.1 strains of SARS-CoV-2. We found that a licensed therapeutic mAb retained neutralization breadth against SARS-CoV-2 variants when expressed as IgG3, but not IgG1. These data highlight that IgG subclasses are not only important for fine-tuning effector functionality but also for binding and neutralization of antigenically drifted viruses.
The fragility of artists’ reputations from 1795 to 2020
Authors: Zhang Letian , Banerjee Mitali , Wang Shinan , Hong Zhuoqiao
Published: August 2023

This study explores the longevity of artistic reputation. We empirically examine whether artists are more- or less-venerated after their death. We construct a massive historical corpus spanning 1795 to 2020 and build separate word-embedding models for each five-year period to examine how the reputations of over 3,300 famous artists—including painters, architects, composers, musicians, and writers—evolve after their death. We find that most artists gain their highest reputation right before their death, after which it declines, losing nearly one SD every century. This posthumous decline applies to artists in all domains, includes those who died young or unexpectedly, and contradicts the popular view that artists’ reputations endure. Contrary to the Matthew effect, the reputational decline is the steepest for those who had the highest reputations while alive. Two mechanisms—artists’ reduced visibility and the public’s changing taste—are associated with much of the posthumous reputational decline. This study underscores the fragility of human reputation and shows how the collective memory of artists unfolds over time.
Targeted evolution of adeno-associated virus capsids for systemic transgene delivery to microglia and tissue-resident macrophages
Authors: Young Adam , Neumann Bjoern , Segel Michael , Chen Civia Zi-Yu , Tourlomousis Panagiotis , Franklin Robin J. M.
Published: August 2023

Tissue macrophages, including microglia, are notoriously resistant to genetic manipulation. Here, we report the creation of Adeno-associated viruses (AAV) variants that efficiently and widely transduce microglia and tissue macrophages in vivo following intravenous delivery, with transgene expression of up to 80%. We use this technology to demonstrate manipulation of microglia gene expression and microglial ablation, thereby providing invaluable research tools for the study of these important cells.
NLRP3 is essential for neutrophil polarization and chemotaxis in response to leukotriene B4 gradient
Authors: Van Bruggen Stijn , Jarrot Pierre-André , Thomas Eline , Sheehy Casey E. , Silva Camila M. S. , Hsu Alan Y. , Cunin Pierre , Nigrovic Peter A. , Gomes Edgar R. , Luo Hongbo R. , Waterman Clare M. , Wagner Denisa D.
Published: August 2023

Neutrophil recruitment to sites of infection and inflammation is an essential process in the early innate immune response. Upon activation, a subset of neutrophils rapidly assembles the multiprotein complex known as the NLRP3 inflammasome. The NLRP3 inflammasome forms at the microtubule organizing center, which promotes the formation of interleukin (IL)-1β and IL-18, essential cytokines in the immune response. We recently showed that mice deficient in NLRP3 (NLRP3
−/−
) have reduced neutrophil recruitment to the peritoneum in a model of thioglycolate-induced peritonitis. Here, we tested the hypothesis that this diminished recruitment could be, in part, the result of defects in neutrophil chemotaxis. We find that NLRP3
−/−
neutrophils show loss of cell polarization, as well as reduced directionality and velocity of migration toward increasing concentrations of leukotriene B4 (LTB4) in a chemotaxis assay in vitro, which was confirmed through intravital microscopy of neutrophil migration toward a laser-induced burn injury of the liver. Furthermore, pharmacologically blocking NLRP3 inflammasome assembly with MCC950 in vitro reduced directionality but preserved nondirectional movement, indicating that inflammasome assembly is specifically required for polarization and directional chemotaxis, but not cell motility per se. In support of this, pharmacological breakdown of the microtubule cytoskeleton via nocodazole treatment induced cell polarization and restored nondirectional cell migration in NLRP3-deficient neutrophils in the LTB4 gradient. Therefore, NLRP3 inflammasome assembly is required for establishment of cell polarity to guide the directional chemotactic migration of neutrophils.
Specific inhibition of an anticancer target, polo-like kinase 1, by allosterically dismantling its mechanism of substrate recognition
Authors: Park Jung-Eun , Kirsch Klara , Lee Hobin , Oliva Paola , Ahn Jong Il , Ravishankar Harsha , Zeng Yan , Fox Stephen D. , Kirby Samuel A. , Badhwar Pooja , Andresson Thorkell , Jacobson Kenneth A. , Lee Kyung S.
Published: August 2023

Polo-like kinase 1 (Plk1) is considered an attractive target for anticancer therapy. Over the years, studies on the noncatalytic polo-box domain (PBD) of Plk1 have raised the expectation of generating highly specific protein–protein interaction inhibitors. However, the molecular nature of the canonical PBD-dependent interaction, which requires extensive water network–mediated interactions with its phospholigands, has hampered efforts to identify small molecules suitable for Plk1 PBD drug discovery. Here, we report the identification of the first allosteric inhibitor of Plk1 PBD, called Allopole, a prodrug that can disrupt intracellular interactions between PBD and its cognate phospholigands, delocalize Plk1 from centrosomes and kinetochores, and induce mitotic block and cancer cell killing. At the structural level, its unmasked active form, Allopole-A, bound to a deep Trp-Phe-lined pocket occluded by a latch-like loop, whose adjoining region was required for securely retaining a ligand anchored to the phospho-binding cleft. Allopole-A binding completely dislodged the L2 loop, an event that appeared sufficient to trigger the dissociation of a phospholigand and inhibit PBD-dependent Plk1 function during mitosis. Given Allopole’s high specificity and antiproliferative potency, this study is expected to open an unexplored avenue for developing Plk1 PBD-specific anticancer therapeutic agents.
Fungal COP9 signalosome assembly requires connection of two trimeric intermediates for integration of intrinsic deneddylase
Authors: Bakti Fruzsina , Stupperich Helena , Schmitt Kerstin , Valerius Oliver , Köhler Anna M. , Meister Cindy , Strohdiek Anja , Harting Rebekka , Sasse Christoph , Heimel Kai , Neumann Piotr , Ficner Ralf , Braus Gerhard H.
Published: August 2023

The conserved eight-subunit COP9 signalosome (CSN) is required for multicellular fungal development. The CSN deneddylase cooperates with the Cand1 exchange factor to control replacements of E3 ubiquitin cullin RING ligase receptors, providing specificity to eukaryotic protein degradation.
Aspergillus nidulans
CSN assembles through a heptameric pre-CSN, which is activated by integration of the catalytic CsnE deneddylase. Combined genetic and biochemical approaches provided the assembly choreography within a eukaryotic cell for native fungal CSN. Interactomes of functional GFP-Csn subunit fusions in pre-CSN deficient fungal strains were compared by affinity purifications and mass spectrometry. Two distinct heterotrimeric CSN subcomplexes were identified as pre-CSN assembly intermediates. CsnA-C-H and CsnD-F-G form independently of CsnB, which connects the heterotrimers to a heptamer and enables subsequent integration of CsnE to form the enzymatically active CSN complex. Surveillance mechanisms control accurate Csn subunit amounts and correct cellular localization for sequential assembly since deprivation of Csn subunits changes the abundance and location of remaining Csn subunits.
Graphene oxide–polyamine preprogrammable nanoreactors with sensing capability for corrosion protection of materials
Authors: Yang Kou , Hu Zhitao , Li Xiaolai , Nikolaev Konstantin , Hong Gan Kai , Mamchik Natalia , Erofeev Ivan , Mirsaidov Utkur M. , Castro Neto Antonio H. , Blackwood Daniel J. , Shchukin Dmitry G. , Trushin Maxim , Novoselov Kostya S. , Andreeva Daria V.
Published: August 2023

Corrosion is one of the major issues for sustainable manufacturing globally. The annual global cost of corrosion is US$2.5 trillion (approximately 3.4% of the world’s GDP). The traditional ways of corrosion protection (such as barriers or inhibiting) are either not very effective (in the case of barrier protection) or excessively expensive (inhibiting). Here, we demonstrate a concept of nanoreactors, which are able to controllably release or adsorb protons or hydroxides directly on corrosion sites, hence, selectively regulating the corrosion reactions. A single nanoreactor comprises a nanocompartment wrapped around by a pH-sensing membrane represented, respectively, by a halloysite nanotube and a graphene oxide/polyamine envelope. A nanoreactor response is determined by the change of a signaling pH on a given corrosion site. The nanoreactors are self-assembled and suitable for mass-line production. The concept creates sustainable technology for developing smart anticorrosion coatings, which are nontoxic, selective, and inexpensive.
Feeling poor or feeling poorer: comparing subjective measures of income in predicting health and well-being (Sentirse pobre o más pobre: comparación de medidas subjetivas del nivel de ingresos en la predicción de la salud y el bienestar)
Authors: Gilbert Karen M. , Weissman David , Gordils Jonathan , Elliot Andrew , Sommet Nicolas
Published: August 2023

Separate areas of research have found that need-based and relative-based operationalizations of subjective income are important for health. Need- and relative-based measures are conceptually distinct, but differential implications for downstream outcomes have never been directly tested. In the present study, US residents ( N = 844) reported their subjective-need and subjective-relative income, as well as their health and well-being. Subjective-need and subjective-relative had distinct and sometimes opposing associations with mental and physical health. Individuals who reported that their income adequately met their needs reported higher life satisfaction, meaning in life and positive affect, and lower physical health symptoms, mental health symptoms and negative affect. Individuals who reported that their income was higher than others reported higher life satisfaction, meaning in life and positive affect, as well as higher physical health symptoms, mental health symptoms and negative affect. The present work provides a nuanced perspective on the operationalizations of subjective income and implications for psychological outcomes.
Remarks on the quasi-position representation in models of generalized uncertainty principle
Authors: Herkenhoff Gomes André
Published: August 2023

This note aims to elucidate certain aspects of the quasi-position representation frequently used in the investigation of one-dimensional models based on the generalized uncertainty principle (GUP). We specifically focus on two key points: (i) contrary to recent claims, the quasi-position operator can possess physical significance even though it is non-Hermitian, and (ii) in the quasi-position representation, operators associated with the position, such as the potential energy, also behave as a derivative operator on the quasi-position coordinate, unless the method of computing expectation values is modified. The development of both points revolves around the observation that the position and quasi-position operators share the same set of eigenvalues and are connected through a non-unitary canonical transformation. This outcome may have implications for widely referenced constraints on GUP parameters.
Smoldering fire detection using low-power capacitive MEMS hydrogen sensor for future fire alarm
Authors: Hayashi Yumi , Akimoto Yosuke , Hiramatsu Naoki , Masunishi Kei , Saito Tomohiro , Yamazaki Hiroaki , Nakamura Naofumi , Kojima Akihiro
Published: August 2023

In this study, we demonstrated detection of a smoldering fire using a low-power hydrogen sensor. To detect the low levels of hydrogen gas generated by smoldering fires, we used a capacitive MEMS hydrogen sensor with a microheater. The microheater accelerates the reduction of palladium oxide on the surface of the sensing film by hydrogen. Thus, more hydrogen is entrapped within the sensing film, and the sensitivity to ppm amounts of hydrogen is improved. The low thermal capacity and high thermal resistance of the structure enabled localized heating of the sensitive film at high speed (1 ms), thereby achieving sub-mW low power consumption by intermittent sensing. The fabricated hydrogen sensor was installed in a small wireless module and placed on a ceiling 3 m from a smoldering cotton fire. Our hydrogen sensor successfully detected 66 ppm hydrogen generated by the fire, and also detected the decrease in hydrogen by room exhaust.
The working mechanism of CsPbI3/Sb2S3 heterojunction perovskite solar cells
Authors: Gu Shiyao , Wang Ruiying , Yang Shi-e , Gu Jinhua , Wang Xiaoxia , Liu Ping , Chen Yongsheng
Published: August 2023

Recently, significant breakthroughs in power conversion efficiencies (PCEs) have been obtained for 3D CsPbI3-based perovskite solar cells. In the present work, a novel heterojunction structure with 1D Sb2S3 as the hole transport layer was designed and investigated using solar cell capacitance simulator simulation software. The influence of thickness, band offset, conduction type, doping concentration, bulk and interface defect densities on the performances of the devices were analyzed. The PCE of the devices increases with the increase in the thicknesses of the CsPbI3 and Sb2S3 layers. The p-type conduction of the CsPbI3 under-layer has more advantages with regard to broadening of the doping density, and the higher acceptor density in the Sb2S3 over-layer contributes to the improvement of the performance of the device. In addition, the device performance is more sensitive to the defect density at the CsPbI3/Sb2S3 interface than that in the Sb2S3 over-layer. Finally, a PCE over 20% is obtained for the device with optimal parameters. These simulation results demonstrate the tremendous potential of a novel 3D/1D CsPbI3/Sb2S3 heterojunction design for high-performance and high-stability devices.
Mechanism of droplet ejection from liquid gallium interacting with inductively coupled hydrogen plasma
Authors: Hamana Yuki , Shirai Naoki , Sasaki Koichi
Published: August 2023

In this study, we observed droplet ejection from liquid gallium interacting with an inductively coupled hydrogen plasma. We observed the formation of a bubble in the liquid gallium, and the droplet ejection was synchronized with the burst of the bubble. We examined droplet ejection frequency by varying the ion flux

[
(
0.2

–7.1) × 1014 cm

−
2

 

s

−
1

]

, the ion energy (15–215 eV), and the liquid gallium temperature (370 K–500 K). As a result, we found that the droplet ejection frequency increased with the ion flux and the liquid gallium temperature, whereas it decreased with the ion energy. We observed that the inside of the bubble in the liquid gallium was occupied by hydrogen. Furthermore, the amount of hydrogen dissolved in the liquid gallium was dependent on the discharge conditions. On the basis of the experimental results, we have proposed a mechanism for bubble formation and droplet ejection. The key in the mechanism is the supersaturated dissolution of hydrogen due to the ion irradiation.
Spinteract: a program to refine magnetic interactions to diffuse scattering data
Authors: Paddison Joseph A M
Published: August 2023

Magnetic diffuse scattering—the broad magnetic scattering features observed in neutron-diffraction data above a material’s magnetic ordering temperature—provides a rich source of information about the material’s magnetic Hamiltonian. However, this information has often remained under-utilised due to a lack of available computer software that can fit values of magnetic interaction parameters to such data. Here, an open-source computer program, Spinteract, is presented, which enables straightforward refinement of magnetic interaction parameters to powder and single-crystal magnetic diffuse scattering data. The theory and implementation of this approach are summarised. Examples are presented of refinements to published experimental diffuse-scattering data sets for the canonical antiferromagnet MnO and the highly-frustrated classical spin liquid Gd3Ga5O12. Guidelines for data collection and refinement are outlined, and possible developments of the approach are discussed.
A static stiffness reference object for instrumented indentation with integrated fiber Fabry–Perot displacement measuring interferometer
Authors: Cripe Jonathan , Arumugam Kumar , Gerbig Yvonne , Shaw Gordon
Published: August 2023

Instrumented indentation is a technique used for measuring the mechanical response of materials to deformation. The accuracy of these measurements relies on force and displacement values recorded during the indentation process. This paper presents a miniature fused silica parallelogram flexure to serve as a reference object for calibrating the applied indentation force based on Hooke’s law, F = kz, where k is the stiffness of the reference object and z is the displacement of the flexure under force F. This study discusses two independent experimental approaches to determine the stiffness of the flexure. In both cases, the stiffness was calculated from the measured flexure displacement while known forces are applied. In the first method, the displacement is measured using a built-in fiber-based interferometer while reference masses of 100 mg and 200 mg are placed on the flexure. A stiffness of

k
=
(
80.3
±
0.79
)

k
N

m

−
1

is determined with this method. The second method uses a commercial indenter to apply a cyclic force of 100 mN magnitude on the flexure while recording the displacement of the indenter probe. Experiments using a 5 μm and a 50 μm conospherical tip estimate the stiffness to be

k
=
(
80.74
±
0.79
)

k
N

m

−
1

, and

(
80.55
±
0.33
)

k
N

m

−
1

respectively.

Disclaimer: Certain commercial equipment, instruments are identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
Scale value guided Lite-FCOS for pointer meter reading recognition
Authors: Wang Zhaolin , Tian Lianfang , Du Qiliang , An Yi , Sun Zhengzheng , Liao Wenzhi
Published: August 2023

As intelligent power grid construction advances, substation inspection becomes crucial, particularly in identifying meter readings. Existing meter reading methods are mainly based on the relationship between pointer and scale. However, these methods commonly suffer from the issue of over-relying on prior reading information, limiting readings to known meters. Hereby in this paper, we propose a method reaching more accurate and robust performance for meter reading by utilizing the unnoticed scale value. We determine the meter pointer direction with the aid of Hough transform and the pointer distribution. To detect meters from the scene as well as obtain scale values and pointers from the meter dial, we build an object detection network, named Lite-FCOS, whose backbone adopts a fast global context network that is lightweight and is of powerful feature extraction capabilities. For training these, meter dial detection dataset and dial reading information dataset are constructed. Lite-FCOS achieves 94.4 mAP50 and 96.7 mAP50 on the above two datasets with only 4.2 M parameters and 56.2 FPS. The entire pointer meter reading recognition process only spends 52 ms on an RTX 3080Ti with a successful meter reading rate (SMR rate) of 89.6%, which indicates that the proposed method achieves promising accuracy and speed.
Three-dimensional control of the light propagation in a defect photonic crystal
Authors: Bravo A J , Aslla Q A P , Huamán-Romaní Y L , Seminario M M V , Sánchez P M G
Published: August 2023

In this paper, we have proposed a new model for controlling the light propagation in a defect photonic crystal structure with a dispersive defect layer. The defect layer consists of a four-level quantum wells interacts by two optical vortex lights. Here, a weak signal light can be generated due to the four-wave mixing mechanism, and this led to phase dependent of the medium. By intensity modulations of the applied lights, we study the 3D properties of the transmitted, reflected and absorption spectrums of the incident light from defect photonic crystal. We have shown that via azimuthal modulations of the optical vortex light the incident light can be absorbed or amplified easily.
A high-frequency SSVEP-BCI system based on a 360 Hz refresh rate
Authors: Liu Ke , Yao Zhaolin , Zheng Li , Wei Qingguo , Pei Weihua , Gao Xiaorong , Wang Yijun
Published: August 2023

Objective. Steady-state visual evoked potential (SSVEP) based brain–computer interfaces (BCIs) often struggle to balance user experience and system performance. To address this challenge, this study employed stimuli in the 55–62.8 Hz frequency range to implement a 40-target BCI speller that offered both high-performance and user-friendliness. Approach. This study proposed a method that presents stable multi-target stimuli on a monitor with a 360 Hz refresh rate. Real-time generation of stimulus matrix and stimulus rendering was used to ensure stable presentation while reducing the computational load. The 40 targets were encoded using the joint frequency and phase modulation method, offline and online BCI experiments were conducted on 16 subjects using the task discriminant component analysis algorithm for feature extraction and classification. Main results. The online BCI system achieved an average accuracy of 88.87% ± 3.05% and an information transfer rate of 51.83 ± 2.77 bits min−1 under the low flickering perception condition. Significance. These findings suggest the feasibility and significant practical value of the proposed high-frequency SSVEP BCI system in advancing the visual BCI technology.
Effect of walking height on movement of individuals and crowds in a corridor
Authors: Li Maoyu , Zhou Zhizuan , Zhang Ping , Jiang Nan , Jia Xinmiao , Ju Xiaoyu , Yang Lizhong
Published: August 2023

The safe and efficient evacuation of pedestrians in an emergency has been widely investigated in the past. Stooping is a common walking posture of pedestrians in evacuation. Understanding the basic laws of pedestrian movement with stoop posture is instructive for developing effective evacuation management in an emergency. However, the evacuation behaviors and movement characteristics of stooped pedestrians are still unclear. In this study, a series of experiments on individuals and crowds with different walking heights were conducted in an 18 m long corridor. It was found that a left-deflection phenomenon appears in the transition from upright walking to stooped walking, and the deflection angles of pedestrians decrease with increasing walking height. The influence of walking height on pedestrian velocity is revealed through the comparison of individual and crowd movement. Restricted walking height can promote the movement velocity of individuals at low speed levels, and weakens the velocity at high speed levels. In contrast to the individual, the velocities of crowds at different speed levels will be enhanced by restricted walking height. Generally, pedestrian movement is affected by the initial motivation, walking height and pedestrian density. Restricted walking height has an encouraging effect in the motivation of pedestrian movement but can increase the physical discomfort of pedestrians. Besides, crowd density has an inhibitory effect on pedestrian movement, and restricted walking height can alleviate high crowd density, implying that appropriate stoop movement can facilitate pedestrian traffic and evacuation to some extent.
Search for supersymmetric sleptons and charginos with the ATLAS detector
Authors: Ballabene Eric
Published: August 2023

A new search for the electroweak production of supersymmetric particles decaying into two
leptons with missing transverse momentum is presented. Two simplified models are considered:
direct pair production of sleptons decaying into the lightest neutralinos through leptons of the
Standard Model (SM) and direct pair production of the lightest charginos decaying into the
lightest neutralinos through W bosons of the SM. The analysis targets phase space regions where
the difference in mass between the slepton or the lightest chargino and the lightest neutralino is
close to or below the mass of the W boson. Such regions with compressed mass spectra have not
been covered by any searches conducted so far due to the low cross-section of the supersymmetric
signal. Therefore, improved analysis strategies are crucial to separate the supersymmetric signal
from the SM backgrounds. A search for an excess of same-flavour lepton pairs in opposite-sign
lepton events is made in the direct slepton pair production analysis while a machine learning
approach using boosted decision trees is exploited in the chargino pair production analysis and
considering both the same-flavour and different-flavour channels. No significant excesses over the
expected background are observed using proton-proton collisions data collected by the ATLAS
experiment at √s = 13 TeV and exclusion limits at 95% confidence level are set for each
considered model. Exclusion limits are also set for selectrons and smuons separately and portions
of the region excluded by the search of smuons pair production are expected to be compatible with
the g-2 anomaly for small tanβ values.
EASpy: fast simulation of fluorescence and Cherenkov light from extended air showers at large zenith angles
Authors: Baktash Ali , Horns Dieter
Published: August 2023

The detailed simulation of extended air showers (EAS) and
their emission of Cherenkov and fluorescence light requires
increasing computation time and storage volume with increasing
energy of the primary particle. Given these limitations, it is
currently challenging to optimize configurations of imaging air
Cherenkov telescopes at photon energies beyond approximately
100 TeV. Additionally, the existing simulation frameworks are not
capable of capturing the interplay of Cherenkov and fluorescence
light emission at large zenith angle distances (≳ 70°),
where the collection area of Cherenkov telescopes considerably
increases. Here, we present EASpy, a framework for the
simulation of EAS at large zenith angles using parametrizations for
electron-positron distributions. Our proposed approach for the
emission of fluorescence and Cherenkov light and the subsequent
imaging of these components by Imaging Atmospheric Cherenkov
Telescopes (IACTs) aims to provide flexibility and accuracy while at
the same time it reduces the computation time considerably compared
to full Monte Carlo simulations. We find excellent agreement of the
resulting Cherenkov images when comparing results obtained from
EASpy with the de-facto standard simulation tool
CORSIKA and sim_telarray. In the process of
verifying our approach, we have found that air shower images appear
wider and longer with increasing impact distance at large zenith
angles, an effect that has previously not been noted. We also
investigate the distribution of light on the ground for fluorescence
and Cherenkov emission and highlight their key differences to
distributions at moderate zenith angles.
Effect of nitriding temperature and its effects on the corrosion and wear resistance of 304 austenitic stainless steel
Authors: Peng Tianxiang , Wang Liang
Published: August 2023

Rapid plasma nitriding of AISI 304 austenitic stainless steel (304SS) was carried out at 440, 460 °C and 480 °C for 1 h in a mixture of NH3 and N2 with a ratio of 1:2. The phase composition, thickness of nitrided layer and properties of wear, and corrosion resistance were evaluated. After nitriding at 480 °C for 1 h, a 6.3 μm the thick nitrided layer was achieved. The influence of the nitriding process on the microstructure, morphology, hardness, corrosion, and wear resistance of the nitrided layers were also studied. Compared with unnitrided 304SS, the wear and corrosion resistances were substantially improved.
Interface effects on titanium growth on graphene
Authors: Zagler Georg , Trentino Alberto , Mustonen Kimmo , Mangler Clemens , Kotakoski Jani
Published: August 2023

Poor quality interfaces between metal and graphene cause non-linearity and impair the carrier mobility in graphene devices. Here, we use aberration corrected scanning transmission electron microscopy to observe hexagonally close-packed Ti nano-islands grown on atomically clean graphene, and establish a 30∘ epitaxial relationship between the lattices. Due to the strong binding of Ti on graphene, at the limit of a monolayer, the Ti lattice constant is mediated by the graphene epitaxy, and compared to bulk Ti, is strained by ca. 3.7% to a value of 0.306(3) nm. The resulting interfacial strain is slightly greater than what has been predicted by density functional theory calculations. Our early growth stage investigations also reveal that, in contrast to widespread assumptions, Ti does not fully wet graphene but grows initially in islands with a thickness of 1–2 layers. Raman spectroscopy implies charge transfer between the Ti islands and graphene substrate.
Synthesis, microstructure and electrochemical properties of Ni-P-based alloy coatings for hydrogen evolution reaction in alkaline media
Authors: Gaikwad A P , Banerjee Atindra Mohan , Pai M R , Dheeman Rajat , Kumar Sanjay , Tripathi A K
Published: August 2023

Alkaline water electrolysis driven by renewable energy is a promising technology for green hydrogen generation. The cathode half-cell reaction i.e., the hydrogen evolution reaction (HER) in alkaline water electrolysis suffers from slow kinetics. Ni-P-based alloys have shown to be an efficient and cost-effective electrocatalyst to accelerate the HER rate. In this study, three Ni-P alloy coatings are prepared via electrodeposition by varying the deposition currents viz. 10 mA cm-2 direct, 10 mAcm-2 and 100 mAcm-2 pulsed currents. The XRD patterns of all the Ni-P coatings exhibited the formation of crystalline deposits and confirmed the alloying of P in Ni. The SEM images suggested that the microstructures of the Ni-P alloy deposits are highly dependent on the magnitude and waveform of the applied current employed during preparation of the alloy coatings. The composition of the alloy surface is Ni-rich in all three cases but exhibited local variations as evaluated by EDX. The surface distributions of Ni and P in the pulsed deposited samples are more uniform and homogeneous. The cyclic voltammetry patterns of the Ni-P coatings in KOH media exhibit characteristic peaks due to Ni/Ni3+ redox phenomenon. The Ni2+/Ni3+ oxidation peak area is lowest for the direct deposited sample and highest for the pulsed deposited one (100 mAcm-2). The Ni-P alloy electrocatalyst deposited under pulsed mode at 100 mAcm-2 exhibits a current density of −10 mAcm-2 at 0.09 V overpotential and is most active among all samples. The remarkable electrocatalytic activity of this sample is attributed to its smaller crystallite size, better morphological characteristics and lesser resistances to charge transfer and porosity.