bluuebunny/crossref_metadata_2025 huggingface dataset:
Recycling waste aluminium foil to bio-acceptable nano photocatalysts [aluminium oxide (Al2O3) & aluminium oxyhydroxide (AlOOH)]; dye degradation as proof-of-concept
Authors: Sharma Bunty , Sahi Arshdeep , Dhau Jaspreet , Kaushik Ajeet , Kumar Rajeev , Chaudhary Ganga Ram
Published: September 2024

Herein we report the reuse of waste aluminium foil for the development of efficient photocatalysts for photodegradation of dye under visible light.
Precise diagnosis of tumor cells and hemocytes using ultrasensitive, stable, selective cuprous oxide composite SERS bioprobes assisted with high-efficiency separation microfluidic chips
Authors: Xie Yujiao , Xu Lei , Zhang Jiahao , Zhang Chenguang , Hu Yue , Zhang Zhouxu , Chen Guoxin , Qi Shuyan , Xu Xiawei , Wang Jing , Ren Wenzhi , Lin Jie , Wu Aiguo
Published: September 2024

In this study, we reported a flower-like Cu2O@Ag SERS substrate for distinguish three types of cancer cells from white blood cells by using machine learning-assisted LDA, after separating cancer cells from blood samples via a microfluidic chip.
Tuning the circularly polarized phosphorescence of platinum(ii) complexes through a chiral cation strategy
Authors: Ren Jiajia , He Tengfei , Lu Haolin , Wang Hebin , Shao Tianyin , Wang Zhaoyu , Zhang Yunxin , Gull Sehrish , Chi Yun , Zhong Yu-Wu , Chen Yongsheng , Long Guankui
Published: September 2024

A novel chiral cation strategy to construct circularly polarized phosphorescent platinum(ii) complexes with luminescence asymmetry factors of +1.4/−1.8 × 10−3 for R/S-ABA·[Pt(ppy)Cl2] and +4.4/−2.8 × 10−3 for R/S-MBA·[Pt(ppy)Cl2].
In situ pyrolysis of Mn-doped MOF-74 metal–organic framework derived MCNOx catalysts for enhanced low-temperature catalytic performance of toluene
Authors: Qu Guangfei , Yang Yixin , Xu Youxiao , Zhao Chenyang , Ning Ping
Published: September 2024

This paper focuses on the use of catalysts generated from metal–organic frameworks (MOFs) for the degradation of toluene in a linked non-thermal plasma/photocatalytic process.
Unactivated alkylsulfinic acids as an alkyl radical source for the synthesis of 3,3-dialkylindolin-2-ones via an electron donor–acceptor complex
Authors: Natarajan Palani , Partigya  , Meena
Published: September 2024

Using unactivated alkylsulfinic acids as an alkyl radical source, a visible-light-assisted method for the alkylation/annulation of N-arylacrylamides has been developed. It is also suitable for the synthesis of progesterone antagonists and amedalin.
Phosphine-controlled divergent reactions of MBH-carbonates with azaheptafulvenes: access to o-anilinyl diene and benzazepine derivatives
Authors: Hao Wei , Zhang Yiwen , Han Xiao , Wang Zhen , Yao Weijun
Published: September 2024

A phosphine controlled divergent cascade reaction of MBH-carbonates with azaheptafulvenes was disclosed. PPh3 provided o-aminophenyl diene while PCy3 offered benzazepine derivative through formal [8 + 3] annulation/ring contraction cascade.
Correction: Near-infrared light triggered photothermal therapy and enhanced photodynamic therapy with a tumor-targeting hydrogen peroxide shuttle
Authors: Wang Bing , Lin Weiming , Mao Zhengwei , Gao Changyou
Published: September 2024

Correction for ‘Near-infrared light triggered photothermal therapy and enhanced photodynamic therapy with a tumor-targeting hydrogen peroxide shuttle’ by Bing Wang et al., J. Mater. Chem. B, 2018, 6, 3145–3155, https://doi.org/10.1039/C8TB00476E.
Constraints on the primordial misalignment of star-disk systems
Authors: Kuffmeier M. , Pineda J. E. , Segura-Cox D. , Haugbølle T.
Published: September 2024

A consensus prevails with regard to star-disk systems accreting most of their mass and angular momentum during the collapse of a prestellar core. However, recent results have indicated that stars experience post-collapse or late infall, during which the star and its disk are refreshed with material from the protostellar environment through accretion streamers. Apart from adding mass to the star-disk system, infall potentially supplies a substantial amount of angular momentum, as the infalling material is initially not bound to the collapsing prestellar core. We investigate the orientation of infall on star-disk systems by analyzing the properties of accreting tracer particles in three-dimensional magnetohydrodynamical (3D MHD) simulations of a molecular cloud that is (4 pc)3 in volume. In contrast to the traditional picture, where the rotational axis is inherited from the collapse of a coherent pre-stellar core, the orientation of star-disk systems changes substantially throughout the accretion process, thereby extending the possibility of primordial misalignment as the source of large obliquities. In agreement with previous results that show larger contributions of late infall for increasing stellar masses, a misaligned infall is more likely to lead to a prolonged change in orientation for stars of higher final mass. On average, brown dwarfs and very low mass stars are more likely to form and accrete all of their mass as part of a multiple system, while stars with final masses above a few 0.1 M⊙ are more likely to accrete part of their mass as single stars. Finally, we find an overall trend among our sample: the post-collapse accretion phase is more anisotropic than the early collapse phase. This result is consistent with a scenario of Bondi-Hoyle-Littletlon accretion during the post-collapse phase, while the initial collapse is less anisotropic – despite the fact that material is funneled through accretion channels.
An analysis of spectroscopic, seismological, astrometric, and photometric masses of pulsating white dwarf stars
Authors: Calcaferro Leila M. , Córsico Alejandro H. , Uzundag Murat , Althaus Leandro G. , Kepler S. O. , Werner Klaus
Published: September 2024

Context. A central challenge in the field of stellar astrophysics lies in accurately determining the mass of stars, particularly when dealing with isolated ones. However, for pulsating white dwarf stars, the task becomes more tractable due to the availability of multiple approaches such as spectroscopy, asteroseismology, astrometry, and photometry, each providing valuable insights into the mass properties of white dwarf stars.

Aims. Numerous asteroseismological studies of white dwarfs have been published, focusing on determining stellar mass using pulsational spectra and comparing it with spectroscopic mass, which uses surface temperature and gravity. The objective of this work is to compare these mass values in detail and, in turn, to compare them with the mass values derived using astrometric parallaxes or distances and photometry data from Gaia, employing astrometric and photometric methods.

Methods. Our analysis involves a selection of pulsating white dwarfs with different surface chemical abundances that define the main classes of variable white dwarfs. We calculated their spectroscopic masses, compiled seismological masses, and determined astrometric masses. We also derived photometric masses, when possible. Subsequently, we compared all the sets of stellar masses obtained through these different methods. To ensure consistency and robustness in our comparisons, we used identical white dwarf models and evolutionary tracks across all four methods.

Results. The analysis suggests a general consensus among the four methods regarding the masses of pulsating white dwarfs with hydrogen-rich atmospheres, known as DAV or ZZ Ceti stars, especially for objects with masses below approximately 0.75 M⊙, although notable disparities emerge for certain massive stars. For pulsating white dwarf stars with helium-rich atmospheres, called DBV or V777 Her stars, we find that astrometric masses generally exceed seismological, spectroscopic, and photometric masses. Finally, while there is agreement among the sets of stellar masses for pulsating white dwarfs with carbon-, oxygen-, and helium-rich atmospheres (designated as GW Vir stars), outliers exist, where mass determinations by various methods show significant discrepancies.

Conclusions. Although a general agreement exists among different methodologies for estimating the mass of pulsating white dwarfs, significant discrepancies are prevalent in many instances. This shows the need to redo the determination of spectroscopic parameters and the parallax and/or improve asteroseismological models for many stars.
Spectral aging analysis of the 3C 219 double-double radio galaxy
Authors: Wolnik K. , Jurusik W. , Jamrozy M.
Published: September 2024

Context. Double-double radio galaxies are characterized by intermittent jet-formation activity. The exact reasons for this behavior are not yet fully understood. Studying these objects and their environment allows us to find common characteristics and compare them with the general population of radio galaxies. 3C 219 is a well-known and thoroughly studied radio galaxy. Among the many explanations for its unusual “partial jet” structure, intermittent activity seems to be the leading one. However, this hypothesis has never been tested using aging analysis.

Aims. The aim of this paper is to put constraints on the active galactic nucleus duty cycle and dynamics of radio lobe expansion in 3C 219, in both the inner and outer double. This will provide us with information on the behavior of the central engine and the interaction of the radio lobes with the ambient medium, allowing us to verify whether the structure of 3C 219 is the result of intermittent activity and to search for its possible causes.

Methods. We performed a spectral aging analysis of the 3C 219 double-double radio galaxy using archival Karl G. Jansky Very Large Array and Low Frequency Array data. We present detailed spectral age maps and constructed a spectral age profile. We compared ratios of linear sizes and luminosities in individual phases of activity with lobe expansion velocities in the plane of the sky derived from the age profile to infer hot-spot advance velocities through the surrounding medium and the orientation of the jet axes.

Results. The galaxy shows a general asymmetry in the distribution of plasma with respect to the inferred jet axis in the original phase of activity, suggesting an influence of the intracluster medium on the formation of the radio structure. The advance speed of hot spots in the outer double is typical of classical FRII sources expanding into an ambient thermal medium, while for the inner double, the lower limit is estimated to be ∼0.28 c. The radio galaxy has experienced a very short quiescent period of no more than 2 Myr, which is ≲7% of its total lifetime.

Conclusions. The most plausible explanation for the double-double radio structure in 3C 219 is a rapid jet reorientation along the line of sight, which may be the result of a minor merger. Further study of the 3C 219 inner double is needed. High-resolution maps are required to probe its structure in sufficient detail, while high-frequency observations are necessary to better constrain the durations of the quiescent and restarted phases.
Probing the physics of star formation (ProPStar)
Authors: Pineda Jaime E. , Soler Juan D. , Offner Stella , Koch Eric W. , Segura-Cox Dominique M. , Neri Roberto , Kuffmeier Michael , Ivlev Alexei V. , Teresa Valdivia-Mena Maria , Sipilä Olli , Jose Maureira Maria , Caselli Paola , Cunningham Nichol , Schmiedeke Anika , Gieser Caroline , Chen Michael , Spezzano Silvia
Published: September 2024

Context. Turbulence is a key component of molecular cloud structure. It is usually described by a cascade of energy down to the dissipation scale. The power spectrum for subsonic incompressible turbulence is ∝k−5/3, while for supersonic turbulence it is ∝k−2.

Aims. We determine the power spectrum in an actively star-forming molecular cloud, from parsec scales down to the expected magnetohydrodynamic (MHD) wave cutoff (dissipation scale).

Methods. We analyzed observations of the nearby NGC 1333 star-forming region in three different tracers to cover the different scales from ∼10 pc down to 20 mpc. The largest scales are covered with the low-density gas tracer 13CO (1–0) obtained with a single dish, the intermediate scales are covered with single-dish observations of the C18O (3–2) line, while the smallest scales are covered in H13CO+ (1–0) and HNC (1–0) with a combination of NOEMA interferometer and IRAM 30m single-dish observations. The complementarity of these observations enables us to generate a combined power spectrum covering more than two orders of magnitude in spatial scale.

Results. We derive the power spectrum in an active star-forming region spanning more than 2 decades of spatial scales. The power spectrum of the intensity maps shows a single power-law behavior, with an exponent of 2.9 ± 0.1 and no evidence of dissipation. Moreover, there is evidence that the power spectrum of the ions to have more power at smaller scales than the neutrals, which is opposite to the theoretical expectations.

Conclusions. We show new possibilities for studying the dissipation of energy at small scales in star-forming regions provided by interferometric observations.
Induction of Labor Using Castor Oil Cocktail – an Analysis of Real-world Data
Authors: Ziegler Stefanie Mona , Heimann Yvonne , Schleussner Ekkehard , Weschenfelder Friederike , Groten Tanja
Published: September 2024

Induction of labor is indicated when benefits of delivery outweigh benefits of prolonged pregnancy, which is not always welcomed by women. Castor oil is accepted as an “old household remedy” for labor induction but is not yet part of the official guidelines. Nevertheless, it is often used, mostly even before the women are admitted to the hospital. Data on its actual benefits and safety are missing. Upon accepting the real-world practice of applying castor oil cocktail for labor induction we added castor oil as one option of labor induction in our clinical routine for multiparous women at term, with a history of at least one vaginal delivery. Here we aimed to generate data on the effectivity and safety of castor oil in labor induction by analyzing the real-world data generated in our cohort.

In our retrospective analysis we included data of a cohort of 148 multiparous women induced by castor oil cocktail and of 286 matched controls receiving established methods according to the current guidelines for labor induction. The castor oil cocktail was prepared following a standardized recipe with quality-tested castor oil. Statistical analysis was performed with SPSS 27.0.

Perinatal outcome data including the rate of vaginal deliveries did not differ between groups, except significantly more neonates were admitted to the neonatal intensive care unit in the group receiving established methods for induction of labor (p = 0.01). In 39 women (26%), administration of castor oil cocktail alone failed to induce labor. The time from initiation of labor induction until delivery was significantly shorter in the castor oil cocktail group (p = 0.04).

Our study demonstrates the safety and effectivity of a castor oil cocktail induction in multiparous women at term in a hospital-based setting using quality-controlled castor oil in a standardized recipe.
Synthesis of Substituted 1-Benzyl-2H-1,2,3-Triazoles by a Click Reaction Using Calcium Carbide as an Acetylene Source
Authors: Fu Rugang , Lei Yuming , Wang Yuyu , Huang Baoqian , Qiu Dong , Wang Junke
Published: September 2024

An effective strategy for constructing substituted 1-benzyl-1H-1,2,3-triazoles was developed through click reactions of benzylic halides with sodium azide and calcium carbide as sources of nitrogen and acetylene, respectively. The advantages of this method are an easily handled inexpensive source of acetylene, a wide range of substrates, satisfactory yields, and simple workup procedures, which could promote the use of calcium carbide as a sustainable acetylene source in modern industrial chemistry.
Obstructive Sleep Apnoea and Type 1 Diabetes Mellitus: A Neglected
Relationship?
Authors: Panou Theodoros , Roukas Konstantinos , Chadia Konstantina , Nena Evangelia , Gouveri Evanthia , Papanas Nikolaos , Steiropoulos Paschalis
Published: September 2024

Obstructive sleep apnoea (OSA) is regarded as a major health condition,
progressively affecting an increased number of people around the world. The
interplay between OSA and type 2 diabetes mellitus (T2DM) has been extensively
studied. However, little is known about the relationship between OSA and type 1
diabetes mellitus (T1DM). This review provides insight into the prevalence of
OSA in T1DM and its relationship with diabetic complications. Studies have
hitherto yielded contradictory results on the occurrence of OSA in T1DM. Indeed,
the risk of OSA in T1DM has ranged from 1 in 10 to more than 1 in 2 T1DM
subjects. This high occurrence was confirmed by objective polysomnography as
well as widely used subjective questionnaires. Multiple studies revealed the
important correlation between OSA and diabetes complications. Both microvascular
(nephropathy, neuropathy and retinopathy) and macrovascular complications appear
to be associated with OSA occurrence, although some associations were not
significant due to inadequate data. In conclusion, T1DM subjects carry a higher
risk of undiagnosed OSA. Additional studies are needed to clarify the exact
correlation between the two conditions.
Mice Engrafted with Human Liver Cells
Authors: de Jong Ype P.
Published: September 2024

Rodents are commonly employed to model human liver conditions, although species differences can restrict their translational relevance. To overcome some of these limitations, researchers have long pursued human hepatocyte transplantation into rodents. More than 20 years ago, the first primary human hepatocyte transplantations into immunodeficient mice with liver injury were able to support hepatitis B and C virus infections, as these viruses cannot replicate in murine hepatocytes. Since then, hepatocyte chimeric mouse models have transitioned into mainstream preclinical research and are now employed in a diverse array of liver conditions beyond viral hepatitis, including malaria, drug metabolism, liver-targeting gene therapy, metabolic dysfunction-associated steatotic liver disease, lipoprotein and bile acid biology, and others. Concurrently, endeavors to cotransplant other cell types and humanize immune and other nonparenchymal compartments have seen growing success. Looking ahead, several challenges remain. These include enhancing immune functionality in mice doubly humanized with hepatocytes and immune systems, efficiently creating mice with genetically altered grafts and reliably humanizing chimeric mice with renewable cell sources such as patient-specific induced pluripotent stem cells. In conclusion, hepatocyte chimeric mice have evolved into vital preclinical models that address many limitations of traditional rodent models. Continued improvements may further expand their applications.
Improving heat tolerance in betel palm (Areca catechu) by characterisation and expression analyses of heat shock proteins under thermal stress
Authors: Alam Osama , Khan Adeel , Khan Wasi Ullah , Khan Waqas Ahmad , Ahmad Mushtaq , Khan Latif Ullah
Published: September 2024

Context Heat shock proteins play a vital role in cellular homeostasis by protecting proteins against various environmental stresses, which facilitates the survival of plants under unfavourable conditions. Aims We aimed to provide the first comprehensive genomic and expression analysis of the HSP70 gene family in betel palm (Areca catechu) to elucidate its role in heat stress response. Methods Genomic analysis revealed 34 putative HSP70 genes distributed across 13 chromosomes. These were renamed AcatHSP70 and classified into five subfamilies (A–E) based on phylogenetic analysis. These genes are mostly localised in the chloroplast, cytoplasm, and nucleus. Gene ontology revealed that these genes are mostly involved in heat stress. The gene duplication events of HSP70 genes involved only segmental duplications. We subjected betel palm seedlings (2 years old) to heat stress under controlled conditions for 30 days at high, low, and room temperatures for expression analyses of HSP70 genes. Key results Expression analysis revealed eight putative candidate genes (AcatHSP70-3, AcatHSP70-13, AcatHSP70-22, AcatHSP70-19, AcatHSP70-21, AcatHSP70-24, AcatHSP70-25, and AcatHSP70-26) that showed significantly higher expression under high-temperature stress. AcatHSP70-5 showed higher expression under low-temperature treatment, and AcatHSP70-16 was responsive at room temperature treatment. Conclusion We conclude that the majority of AcatHSP70 genes play a crucial role under thermal stress conditions, and respond to high-temperature stress as shown by the quantitative reverse transcription polymerase chain reaction analysis. Implications This comprehensive characterisation of the HSP70 gene family provides novel insights into the thermal protection mechanisms of betel palms in changing climates.
Deformation dynamics of nanopores upon water imbibition
Authors: Sanchez Juan , Dammann Lars , Gallardo Laura , Li Zhuoqing , Fröba Michael , Meißner Robert H. , Stone Howard A. , Huber Patrick
Published: September 2024

Capillarity-driven transport in nanoporous solids is widespread in nature and crucial for modern liquid-infused engineering materials. During imbibition, curved menisci driven by high negative Laplace pressures exert an enormous contractile load on the porous matrix. Due to the challenge of simultaneously monitoring imbibition and deformation with high spatial resolution, the resulting coupling of solid elasticity to liquid capillarity has remained largely unexplored. Here, we study water imbibition in mesoporous silica using optical imaging, gravimetry, and high-resolution dilatometry. In contrast to an expected Laplace pressure-induced contraction, we find a square-root-of-time expansion and an additional abrupt length increase when the menisci reach the top surface. The final expansion is absent when we stop the imbibition front inside the porous medium in a dynamic imbibition-evaporation equilibrium, as is typical for transpiration-driven hydraulic transport in plants, especially in trees. These peculiar deformation behaviors are validated by single-nanopore molecular dynamics simulations and described by a continuum model that highlights the importance of expansive surface stresses at the pore walls (Bangham effect) and the buildup or release of contractile Laplace pressures as menisci collectively advance, arrest, or disappear. Our model suggests that these observations apply to any imbibition process in nanopores, regardless of the liquid/solid combination, and that the Laplace contribution upon imbibition is precisely half that of vapor sorption, due to the linear pressure drop associated with viscous flow. Thus, simple deformation measurements can be used to quantify surface stresses and Laplace pressures or transport in a wide variety of natural and artificial porous media.
Blobs form during the single-file transport of proteins across nanopores
Authors: Sauciuc Adina , Whittaker Jacob , Tadema Matthijs , Tych Katarzyna , Guskov Albert , Maglia Giovanni
Published: September 2024

The transport of biopolymers across nanopores is an important biological process currently under investigation for the rapid analysis of DNA and proteins. While the transport of DNA is generally understood, methods to induce unfolded protein translocation have only recently been discovered (Yu et al., 2023, Sauciuc et al., 2023). Here, we found that during electroosmotically driven translocation of polypeptides, blob-like structures typically form inside nanopores, often obstructing their transport and preventing addressing individual amino acids. This is in contrast with the electrophoretic transport of DNA, where the formation of such structures has not been reported. Comparisons between different nanopore sizes and shapes and modifications by different surface chemistries allowed formulating a mechanism for blob formation. We also show that single-file transport can be achieved by using 1) nanopores that have an entry and an internal diameter smaller than the persistence length of the polymer, 2) nanopores with a nonsticky (i.e
.,
nonaromatic) inner surface, and 3) moderate translocation velocities. These experiments provide a basis for understanding polypeptide transport under confinement and for improving the design and engineering of nanopores for protein analysis.
Evaluation of Bosch processing and C4F8 plasma deposition at cryogenic temperatures
Authors: Nos Jack , Dussart Rémi , Tillocher Thomas , Lefaucheux Philippe , Boufnichel Mohamed
Published: September 2024

The Bosch process was studied at a substrate temperature of −100 °C and compared to etchings performed at room temperature, as in the general case. The tests were realized using an inductively coupled plasma reactor by varying C4F8 passivating gas flow injections both at +20 °C and −100 °C. It was observed that the Bosch process is effectively temperature dependent and that the necessary C4F8 passivating gas flow can be reduced to obtain similar anisotropic profiles at −100 °C compared to the ambient temperature process. For example, in one of the studied cases, a fluorocarbon injection of 8 sccm was sufficient to obtain an anisotropic etch rate of up to 4.4 μm min−1 at −100 °C whereas the profile obtained at +20 °C using the same parameters presents lateral etching defects with a reduced etch rate of 2.4 μm min−1. At this point, the C4F8 flow must be increased to 12 sccm (50% more) to retrieve an anisotropic profile with an etch rate of 4.0 μm min−1. In the case of cryogenic Bosch (cryo-Bosch) processing, C4F8 feed dosing has a greater influence on the passivation regime which affects the subsequent etching result but it can be easily refined through the optimization of process parameters. An in-situ ellipsometry study of the deposition rate of C4F8 on both polycrystalline silicon (p-Si) and SiO2 substrates was realized by varying the gas flow at −100 °C and +20 °C. This study shows that the deposited fluorocarbon material is approximately a hundred times thicker at cryogenic temperatures using the same process parameters. Scanning electron microscopy (SEM) observation of these samples are in adequacy with the ellipsometry results. Cryo–Bosch etching also results in a slightly higher etch rate compared to room temperature processing when analyzing similar anisotropic profiles. Si:SiO2 etching selectivity is significantly increased at −100 °C although the aspect-ratio dependent etching phenomenon is more important.
Pressure-induced magnetic and topological transitions in non-centrosymmetric MnIn2Te4
Authors: Bose Anumita , Banerjee Rajdeep , Narayan Awadhesh
Published: September 2024

In recent years, the study of magnetic topological materials, with their variety of exotic physics, has significantly flourished. In this work, we predict the interplay of magnetism and topology in the non-centrosymmetric ternary manganese compound MnIn2Te4 under external hydrostatic pressure, using first-principles calculations and symmetry analyses. At ambient pressure, the ground state of the system is an antiferromagnetic insulator. With the application of a small hydrostatic pressure (∼0.50 GPa), it undergoes a magnetic transition, and the ferromagnetic state becomes energetically favorable. At ∼2.92 GPa, the ferromagnetic system undergoes a transition into a Weyl semimetallic phase, which hosts multiple Weyl points in the bulk. The presence of non-trivial Weyl points have been verified by Wilson bands computations and the presence of characteristic surface Fermi arcs. Remarkably, we discover that the number of Weyl points in this system can be controlled by pressure and that these manifest in an anomalous Hall conductivity (AHC). In addition to proposing a new candidate magnetic topological material, our work demonstrates that pressure can be an effective way to induce and control topological phases, as well as AHC, in magnetic materials. These properties may allow our proposed material to be used as a novel pressure-controlled Hall switch.
Cavity ionization chamber responses in the JAEA and the NMIJ high-energy photon reference fields for radiation protection
Authors: Ishii Junya , Shimizu Morihito , Kato Masahiro , Kurosawa Tadahiro , Tsuji Tomoya , Yoshitomi Hiroshi , Tanimura Yoshihiko , Watabe Hiroshi
Published: September 2024

A dosimeter should ideally be calibrated in a reference field with similar energy and doserate to that which the dosimeter is being used to measure. Environments around nuclear reactors and radiation therapy facilities have high-energy photons with energies exceeding that of 60Co gamma rays, and controlling exposure to these photons is important. The Japan Atomic Energy Agency and National Metrology Institute of Japan have high-energy reference fields with energies above several megaelectronvolts for different types of accelerators. Their reference fields have different fluence-energy distributions. In this study, the energy dependencies of the two-cavity ionization chambers, which are often used by secondary standard laboratories, were experimentally and computationally evaluated for each high-energy field. These results agreed well within the relative expanded uncertainties (k = 2), and their capabilities for air kerma measurements in each high-energy reference field were confirmed. Therefore, the capabilities of the air-kerma measurements were verified in the two high-energy reference fields.
Measurement and machining error assessment method for cycloid pump rotor profile based on STEP
Authors: Xu Kai , Xiao Ying , Dai Zhen , Li Tianxing
Published: September 2024

The contour shape and machining precision of the rotor of an cycloid pump directly determine the sealing performance of the pump cavity. Precise measurement of contour machining errors is a crucial step in the manufacturing process. However, rotor contour curves are often designed by enterprises based on actual engineering needs, leading to inconsistency between the measured baseline contour and the designed contour, thus failing to accurately reflect the actual machining condition of the rotor. Therefore, this paper proposes a method for measuring the contour of the cycloid pump rotor and evaluating machining errors based on the standard for the exchange of product (STEP) files necessary for product design in manufacturing. Firstly, utilizing NX/OPEN API functions, contour coordinate points and unit normal vectors are obtained from the rotor’s STEP design data. Subsequently, by planning the process of measuring the closed continuous contour of the rotor, the transformation between the workpiece coordinate system and the measurement coordinate system is achieved to position the tested rotor, followed by analyzing the influence of different starting points on error measurement and evaluation determines the optimal starting point. Finally, a measurement sampling point strategy is established to collect data points of the actual machining contour of the rotor. By achieving the best matching between the actual machining contour and the measured baseline contour, a contour deviation calculation model is established. Utilizing gauge blocks enables accurate assessment of pitch deviation, radial runout, and tooth-to-tooth distance deviation, resulting in assessment results that better fit the actual meshing situation of the rotor. Experimental results verifies consistency between the measurements of the one-dimensional probe and Gleason measurements. This theory and method not only expand the measurement range of the one-dimensional probe but also provide more accurate and efficient guidance for the flexible machining of the rotor.
Strong-SLAM: real-time RGB-D visual SLAM in dynamic environments based on StrongSORT
Authors: Huang Wei , Zou Chunlong , Yun Juntong , Jiang Du , Huang Li , Liu Ying , Jiang Guo Zhang , Xie Yuanmin
Published: September 2024

The assumptions of a static environment and scene rigidity are important theoretical underpinnings of traditional visual simultaneous localization and mapping (SLAM) algorithms. However, these assumptions are difficult to work in dynamic environments containing non-rigid objects, and cannot effectively handle the characteristics of local areas of non-rigid moving objects, seriously affecting the robustness and accuracy of the SLAM system in localization and mapping. To address these problems, we improved ORB-SLAM3 and proposed a real-time RGB-D visual SLAM framework for dynamic environments based on StrongSORT—Strong-SLAM. First, we combine YOLOv7-tiny with StrongSORT to match the semantic information of dynamic targets. Optical flow and epipolar constraints are then used to initially extract geometric and motion information between adjacent frames. Subsequently, based on an improved adaptive threshold segmentation algorithm and geometric residuals, a background model and a Gaussian residual model are constructed to further extract the geometric information of dynamic targets. Finally, semantic and geometric information are integrated to perform global feature motion level classification, and motion probabilities and optimization weights are defined to participate in global pose estimation and optimization. Experimental results on the publicly available TUM RGB-D dataset show that Strong-SLAM reduces the absolute trajectory error and relative pose error by at least 90% compared to ORB-SLAM3, achieving performance comparable to the most advanced dynamic SLAM solutions.
Hidden layer target spatio-temporal correlation feature regression based soft sensing for industrial process
Authors: Guo Xiaoping , Lu Xiaoyu , Li Yuan
Published: September 2024

The soft sensor modeling method using deep neural networks has been widely adopted. However, issues arise from the layer-by-layer accumulation of target-irrelevant information during feature extraction and the under-exploration of temporal and spatial relationships between hidden layer features, which significantly affects model prediction accuracy. In this paper, we propose a feature regression method called the Hidden Layer Target Spatio-Temporal Correlation Feature Regression method, which simultaneously considers the correlation of hidden layer features with the target and their spatio-temporal correlations. First, we propose a Hidden Layer Target Correlation Auto-Encoder (HTAE) and then construct a deep network by stacking these encoders. In HTAE, the orthogonal typical correlation information between each hidden layer feature and the target variable is calculated. A gated value is utilized for the dynamic adjustment of this information, weighting and replacing the original hidden layer features to obtain deep layer features that are sufficiently correlated with the target. Subsequently, a time-weighted spatially dilated network is built. By incorporating the attention mechanism and dilated convolution to obtain target spatio-temporal correlation features, a fully connected layer is used to construct a feature regression soft sensor model. Simulation experiments are conducted using the debutanizer column and industrial sulfur recovery process, and the proposed method is compared with stacked autoencoder (SAE), variable-wise weighted SAE, spatio-temporal attentional neural network, information complementary fusion SAEs, and stacked spatial–temporal autoencoder (S2TAE) methods to validate its effectiveness.
GPAC-YOLOv8: lightweight target detection for fire scenarios
Authors: Yunyan Wang , Zhangyi Kou
Published: September 2024

Due to the large number of parameters in the deep network model, it is difficult for existing fire detection methods to adapt to limited hardware configurations. In addition, detecting targets in the early stages of a fire is challenging owing to their small size. Therefore, this study presents a novel fire and smoke detection framework called GPAC-YOLOv8, which is based on the YOLOv8 architecture. Firstly, the integration of the ghost module and the Polarized Self-Attention attention mechanism into the backbone culminates in the CGP module, which is designed to improve computational efficiency while maintaining accuracy. Next, an innovative feature fusion module, AC-Neck, is developed through the application of the adaptive spatial feature fusion strategy and the lightweight content-aware reassembly of features upsampling mechanism, aiming to optimize feature map fusion and increase small target detection efficiency. Finally, a Focal-WIoU loss function, augmented with a dual weighting mechanism, is formulated to precisely delineate the aspect ratios of the predicted bounding boxes, thereby strengthening the generalization capacity of the model. Experimental results, derived from the application of the proposed GEAC-YOLOv8 method to a specially constructed dataset, show significant improvements in detection speed while maintaining detection accuracy compared to conventional methods. Thus, the GPAC-YOLOv8 framework demonstrably improves the effectiveness of object detection in fire and smoke scenarios.
Reinforcement learning intermittent optimal formation control for multi-agent systems with disturbances
Authors: Liu Erliang , Miao Guoying , Hu Jingyu
Published: September 2024

This paper investigates disturbance-resistant intermittent event-triggered optimal formation control problems of second-order multi-agent systems by using the reinforcement learning method, which takes into account the influence of network damage including denial-of-service (DoS) and deception attacks, stochastic noises, and unknown external disturbances. Firstly, we propose a novel disturbance observer based on adaptive control to estimate unknown external disturbances under an event-triggered mechanism. Secondly, by use of estimation of disturbances, an innovative intermittent event-triggered optimal formation algorithm is given. By applying theories such as Lyapunov stability and stochastic stability, sufficient conditions are derived to guarantee that all agents achieve the desired formation in mean square sense. Additionally, in the model-free case, the optimal controller is solved using the least squares method, which is computationally less complex than some existing approaches. Finally, the theoretical results are effectively validated through simulation examples.
Robust knowledge transfer for bearing diagnosis in neural network models using multilayer maximum mean discrepancy loss function
Authors: Thuan Nguyen Duc
Published: September 2024

This paper introduces a robust transfer learning method to enhance bearing diagnosis, particularly in cross-machine scenarios. The method trains a shallow neural network using labeled data from a different machine and unlabeled data from the target monitoring machine. To facilitate effective knowledge transfer, a multilayer maximum mean discrepancy loss function is employed, enabling the model to adapt learned features from the source machine to the target machine’s unlabeled data. This approach addresses the challenges of low accuracy and robustness often seen in transfer learning, especially when dealing with different machines. Experiments conducted on the Hanoi University of Science and Technology bearing dataset validate the effectiveness of the proposed method. The results show significant improvements in prediction accuracy and robustness, making this method superior to existing transfer learning models for cross-machine bearing diagnosis.
Combined BDS/5G seamless positioning scheme based on joint switching strategy of satellite elevation angle and CNR in complex urban environments
Authors: Li Fangxin , Tu Rui , Geng Fanyue , Zhang Rui , Zhang Pengfei , Lu Xiaochun
Published: September 2024

Satellite-based positioning has gained popularity, but in bustling urban areas, signals face challenges like serious attenuation, affecting the reliability of positioning. To overcome this, we propose a seamless positioning approach that combines the BeiDou navigation satellite system (BDS) and 5G, specifically designed for complex urban settings. Initially, we establish static and dynamic positioning solutions using real 5G data measured through the time difference of arrival method, resulting in accurate 5G indoor positioning. Following this, we develop a combined BDS/5G positioning model incorporating joint switching based on satellite elevation angle and carrier-to-noise ratio (CNR). We conduct positioning experiments in intricate environments to validate the effectiveness of our model. The experimental outcomes demonstrate that our combined BDS/5G seamless positioning model, employing the joint switching strategy of satellite elevation angle and CNR, achieves impressive positioning accuracies ranging from decimeters to meters. This approach markedly enhances accuracy and reliability of seamless positioning in challenging urban scenarios.
Non-degenerate localised waves beyond Manakov system and their new perspectives
Authors: Pan Liuyi , Wang Lei , Liu Lei , Sun Wenrong , Ren Xiaoxia
Published: September 2024

We study the non-degenerate dynamics of localised waves beyond Manakov system and offer their new perspectives based on the wave component analysis. Our investigation is in the framework of the coupled Hirota (CH) equations. An exact multi-parameter family of solutions for the localised waves is derived within a new Lax pair which is necessary for producing the new types of solutions describing the non-degenerate localised waves, such as the non-degenerate general breathers, non-degenerate Akhmediev breathers, non-degenerate Kuznetsov-Ma solitons and non-degenerate rogue waves. Especially, the degenerate and non-degenerate solutions for rogue waves are different from previous ones, even within the context of the Manakov system. A new technique of wave mode analysis (or the characteristic line analysis) is provided to classify degenerate and non-degenerate solutions beyond the eigenvalue perspectives, namely the critical relative wave number. Such technique is suitable for both the CH equations as well as Manakov system. Hereby, we redefine the non-degenerate localised waves from a fully different view. We further prove that a transition between the non-degenerate localised waves to various types of solitons appears in the CH equations due to the higher-order effects and there is no analogue in Manakov system. In order to further understand such transition dynamics and physical properties of the non-degenerate solutions, the physical spectra are presented analytically. The higher-order terms take impacts on the spectra, for which the state transition solutions as well as a new type of breathers are found. Furthermore, we investigate the relation between non-degenerate modulation instability and higher-order effects. We also offer an exact initial condition to excite the degenerate and non-degenerate localised waves using the numerical simulation and test the stability for the excitation of such solutions by adding a weak perturbation. Since the CH equations can model a large number of physical phenomena in the deep ocean, in the birefringent fibre as well as in the nonlinear channel, our results may provide insights for the related experimental studies.
Electrical and optical characterisation of InGaAsSb-based photodetectors for SWIR applications
Authors: Mamić K , Hanks L A , Fletcher J E , Craig A P , Marshall A R J
Published: September 2024

The

In

x

Ga

1
−

x

A
s

y

Sb

1
−

y

alloy was studied in epilayers and photodiodes grown lattice matched to GaSb across a comprehensive composition range,

0
⩽

x

⩽
0.3

, as a promising technology to support the extended short-wave infrared region

∼
1.7
−
3

µm. Low background carrier concentrations between

6
×

10

14

and

1
×

10

15

cm

−
3

were achieved in all samples, reducing with In fraction. Both the absorption coefficient and external quantum efficiency were found to increase with indium fraction, up to

∼

10

4

cm

−
1

and 70% without an AR coating, respectively. Counter to the fundamental bandgap dependence, leakage current density initially reduced with the addition of low In and As fractions, before rising as the fractions increased and the bandgap reduced further. These properties resulted in specific detectivity reaching a maximum in the sample with x = 0.043, before decreasing towards higher alloy fractions. It is concluded that for moderate In fractions, the InGaAsSb alloy offers clear potential to improve on the disappointing material and photodiode properties of GaSb and support emerging SWIR sensing applications. However, development of fabrication and passivation technology is required to fully exploit this potential.
Detecting and eliminating quantum noise of quantum measurements
Authors: Tang Shuanghong , Zheng Congcong , Wang Kun
Published: September 2024

Quantum measurements are crucial for extracting information from quantum systems, but they are error-prone due to hardware imperfections in near-term devices. Measurement errors can be mitigated through classical post-processing, based on the assumption of a classical noise model. However, the coherence of quantum measurements leads to unavoidable quantum noise that defies this assumption. In this work, we introduce a two-stage procedure to systematically tackle such quantum noise in measurements. The idea is intuitive: we first detect and then eliminate quantum noise. In the first stage, inspired by coherence witness in the resource theory of quantum coherence, we design an efficient method to detect quantum noise. It works by fitting the difference between two measurement statistics to the Fourier series, where the statistics are obtained using maximally coherent states with relative phase and maximally mixed states as inputs. The fitting coefficients quantitatively benchmark quantum noise. In the second stage, we design various methods to eliminate quantum noise, inspired by the Pauli twirling technique. They work by executing randomly sampled Pauli gates before the measurement device and conditionally flipping the measurement outcomes in such a way that the effective measurement device contains only classical noise. We numerically demonstrate the two-stage procedure’s feasibility on the Baidu Quantum Platform. Notably, the results reveal significant suppression of quantum noise in measurement devices and substantial enhancement in quantum computation accuracy. We highlight that the two-stage procedure complements existing measurement error mitigation techniques, and they together form a standard toolbox for manipulating measurement errors in near-term quantum devices.
Dynamical generation of macroscale magnetic fields and fast flows in a four-component astrophysical plasma
Authors: Shazad Usman , Iqbal M
Published: September 2024

We explore the possibility of the generation or amplification of macroscale magnetic fields and flows in a four-component astrophysical dusty plasma composed of mobile massless electrons and positrons, inertial positive ions and negatively charged static dust particles. The investigation demonstrates that when microscopic turbulent ambient plasma energy is predominantly kinetic, a straight dynamo (DY) mechanism is feasible. Conversely, a unified reverse-dynamo/dynamo (RDY/DY) mechanism is possible when the microscopic turbulent ambient plasma energy is primarily magnetic. Additionally, the evolution of Alfvén Mach numbers at the macro- and microscale are significantly affected by plasma species densities and invariant helicities. The potential implications of the present study for astrophysical settings are also highlighted.