bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrinsic and extrinsic relaxation mechanisms for controlling spin current intensity in Fe

100
−

x

Co

x

/Ta bilayers
Authors: Velázquez Rodriguez D , Gómez J E , Avilés-Félix L , Ampuero Torres J L , Torres T E , Pérez Martínez A A , Morbidel L , Goijman D , RojasSánchez J C , Aguirre M H , Milano J , Butera A
Published: June 2024

Controlling the damping parameter in metallic ferromagnetic thin films is a key step for spintronic applications in which spin currents are generated by spin pumping. The coexistence of two states with low and high damping constant values would allow to obtain states of high and low spin current intensity, respectively. We have fabricated Fe

100
−
x

Co
x
/Ta (with nominal x = 0, 15, 20, 25, 30 and 35) bilayers in which the Fe

100
−
x

Co
x
layers grow epitaxially and the Ta layer is polycrystalline. We have found the coexistence of Gilbert damping and two magnon scattering mechanisms linked to a sign change in the magnetocrystalline anisotropy constant that allows the manipulation of low and high intensity states of the measured inverse spin Hall effect voltage. Bilayers with lower Co concentrations (

x
⩽

25%) present different relaxation mechanisms (isotropic Gilbert damping and two magnon scattering) and an extra ferromagnetic resonance linewidth broadening produced due to mosaicity. Bilayers with Co concentration

x
>

25% present a dominating Gilbert damping for all directions in the film plane. However, in this concentration range the damping constant is anisotropic and when the magnetic field is applied along the hard magnetization direction α increases ∼420% with respect to the value obtained for the easy magnetization direction. Coexistence of isotropic Gilbert damping and two magnon scattering generated spin currents 2.5 times larger when the field is applied along the hard magnetization axis compared to the value observed in the easy magnetization axis. Thesefindings make the Fe

100
−
x

Co
x
/Ta system an excellent candidate for spintronic device applications.
Strong magnon-magnon coupling in hexagonal magnetic elements
Authors: Ye Yuchen , Pan Lizi , Mi Shuai , Wang Jianing , Wei Jinwu , Wang Jianbo , Liu Qingfang
Published: June 2024

We achieve strong magnon-magnon coupling experimentally between edge and center modes in patterned hexagonal CoFeB films. The coupling strength is adjustable via the external magnetic field’s direction and the nanomagnet’s aspect ratio. Micromagnetic simulation indicates that the stable existence of the center mode determines the occurrence of coupling, which correlates with the direction of the edge demagnetization field. This work offers a novel perspective on the study of magnon-magnon coupling in a single material, which benefits magnon-based quantum information technology.
Surface defect detection of strip steel based on GT-CutMix augmentation algorithm and improved DSSD model
Authors: Lin Liyuan , Wen Aolin , Wang Ying , Zhao Shuxian , Zhang Shun , Yan Jingpeng , Zhou Yuan , Zhou Weibin
Published: June 2024

Nowadays, defect detection technology based on deep learning continuously increases the surface quality requirements of hot-rolled strip steel. However, due to limitations in industrial production, defect datasets often suffer from insufficient training samples and imbalanced categories. This paper proposes effective solutions, namely the GT-CutMix offline data augmentation algorithm and lightweight small sample defect detection models. The GT-CutMix augmentation algorithm significantly improves defect utilization by accurately sampling defect locations and integrating them into the original data set. We design the S-deconvolutional single shot detector (DSSD) defect detection model by constructing a lightweight SI-MobileNet to replace the ResNet101 backbone of the DSSD network. This can reduce the resource parameters and consumption. At the same time, it can speed up training and inference. To further improve the detection accuracy, we integrate the pyramid split attention (PSA) mechanism into the prediction module of DSSD and construct the SA-DSSD model. Under the GT-CutMix augmentation algorithm, the mAP of S-DSSD and SA-DSSD models on X-SDD dataset are 76.83% and 78.63%, respectively. Meanwhile, the corresponding detection speeds are 45 FPS and 40 FPS, respectively. In addition, on the NEU-DET cross-dataset experiment, the mAP of the SA-DSSD model reaches 74.88%. Our methods are highly effective and generalized for small sample defect detection, which can provide selective solutions for specific needs such as high speed and precision in different industrial production scenarios.
The property of CrCoNiFeMnAl
x
(x=0, 0.5, and 1) high-entropy alloys on rapid cooling: insights from ab initio molecular dynamics
Authors: Wang Luyu , Liu Xinxin , Gao Zhibin
Published: June 2024

High-entropy alloys (HEAs) are currently the subject of extensive research. Despite this, the effects of rapid cooling on their performance have yet to be investigated. This study uses ab initio molecular dynamics to investigate the CrCoFeNiMnAl
x
(x =0, 0.5 and 1) HEAs under a rapid cooling process. It has been observed that the three HEAs all form metallic glass at 300 K under a constant cooling rate of 1.25 × 102 K ps−1, mainly composed of icosahedron and face-centered cubic clusters. Secondly, the glass transition temperatures (T
g) are predicted to be 1658 K for CrCoFeNiMn, 1667 K for CrCoFeNiMnAl0.5, and 1687 K for CrCoFeNiMnAl, respectively. It can be seen the T
g of HEAs increases with the content of Al increasing. Eventually, a relationship between structure and dynamics is established by using the five-fold local symmetry parameters and shear viscosity, which proves that structural evolution is the fundamental reason for dynamic deceleration. The present results contribute to understanding the evolution of the local structure of CrCoFeNiMnAl
x
and provide a new perspective for studying the structural mechanism of dynamic retardation in HEAs.
Construction of recombinant Omp25 or EipB protein loaded PLGA nanovaccines for Brucellosis protection
Authors: Akmayan Ilkgul , Oztav Sedanur , Coksu Irem , Abamor Emrah Sefik , Acar Serap , Ozbek Tulin
Published: June 2024

Safe and effective vaccine candidates are needed to address the limitations of existing vaccines against Brucellosis, a disease responsible for substantial economic losses in livestock. The present study aimed to encapsulate recombinant Omp25 and EipB proteins, knowledged antigen properties, into PLGA nanoparticles, characterize synthesized nanoparticles with different methods, and assessed their in vitro/in vivo immunostimulatory activities to develop new vaccine candidates. The recombinant Omp25 and EipB proteins produced with recombinant DNA technology were encapsulated into PLGA nanoparticles by double emulsion solvent evaporation technique. The nanoparticles were characterized using FE-SEM, Zeta-sizer, and FT-IR instruments to determine size, morphology, zeta potentials, and polydispersity index values, as well as to analyze functional groups chemically. Additionally, the release profiles and encapsulation efficiencies were assessed using UV–Vis spectroscopy. After loading with recombinant proteins, O-NPs reached sizes of 221.2 ± 5.21 nm, while E-NPs reached sizes of 274.4 ± 9.51 nm. The cumulative release rates of the antigens, monitored until the end of day 14, were determined to be 90.39% for O-NPs and 56.1% for E-NPs. Following the assessment of the in vitro cytotoxicity and immunostimulatory effects of both proteins and nanoparticles on the J774 murine macrophage cells, in vivo immunization experiments were conducted using concentrations of 16 µg ml−1 for each protein. Both free antigens and antigen-containing nanoparticles excessively induced humoral immunity by increasing produced Brucella-specific IgG antibody levels for 3 times in contrast to control. Furthermore, it was also demonstrated that vaccine candidates stimulated Th1-mediated cellular immunity as well since they significantly raised IFN-gamma and IL-12 cytokine levels in murine splenocytes rather than IL-4 following to immunization. Additionally, the vaccine candidates conferred higher than 90% protection from the infection according to challenge results. Our findings reveal that PLGA nanoparticles constructed with the encapsulation of recombinant Omp25 or EipB proteins possess great potential to trigger Brucella-specific humoral and cellular immune response.
Optimizing information-driven awareness allocation for controlling activity-triggered epidemic spread
Authors: Chen Jie , Hu Maobin , Cao Jinde
Published: June 2024

In the contemporary era, the advent of epidemics instigates a substantial upswing in relevant information dissemination, bolstering individuals’ resistance to infection by concurrently reducing activity contacts and reinforcing personal protective measures. To elucidate this intricate dynamics, we introduce a composite four-layer network model designed to capture the interplay among information-driven awareness, human activity, and epidemic spread, with a focus on the allocation of individuals’ limited attention in diminishing activity frequency and self-infection rates. One intriguing observation from our findings is an anomalous, concave non-monotonic relationship between awareness trade-off and epidemic spread, with a more pronounced prevalence at an intermediate least awareness efficacy. This underscores the inadvisability of relaxing self-protection through reduced activity frequency or compensating for increased activity frequency by enhancing self-protection. Especially noteworthy is the significance of enhancing self-protection in response to heightened information dissemination and inherent activity demands to curtail infection risk. However, in scenarios with increasing ancillary activity frequency, the emphasis should exclusively shift towards reducing activity exposure. The model establishes a theoretical threshold for accurately predicting awareness efficacy in epidemic outbreaks. Optimal awareness allocation consistently resides at the extremes—either completely avoiding unnecessary activity contact or adopting full self-protection. This guidance, contingent on information level and activity demand, offers valuable insights into the delicate balance between individual behaviors and epidemic prevention.
A symmetric heterogate dopingless electron-hole bilayer TFET with ferroelectric and barrier layers
Authors: Liu Hu , Zhou Xiaoyu , Li Peifeng , Wang Pengyu , Li Yubin , Pan Lei , Zhang Wenting
Published: June 2024

In this paper, a symmetric heterogate dopingless electron–hole bilayer tunnel field-effect transistor with a ferroelectric layer and a dielectric barrier layer (FBHD-EHBTFET) is proposed. FBHD-EHBTFET can not only avoid random doping fluctuation and high thermal budget caused by doping, but also solve the issue that conventional EHBTFETs are unable to use the self-alignment process during device manufacturing. The simultaneous introduction of the symmetric heterogate and dielectric barrier layer can significantly suppress off-state current (I
off). Ferroelectric material embedded in the gate dielectric layer can enhance electron tunneling, contributing to improving on-state current (I
on) and steepening average subthreshold swing (SS
avg). By optimizing various parameters related to the gate, ferroelectric layer, and dielectric barrier layer, FBHD-EHBTFET can obtain the I
off of 1.11 × 10–18 A μm−1, SS
avg of 12.5 mV/dec, and I
on of 2.59 × 10–5 A μm−1. Compared with other symmetric dopingless EHBTFETs, FBHD-EHBTFET can maintain high I
on while reducing its I
off by up to thirteen orders of magnitude and SS
avg by at least 51.2%. Moreover, investigation demonstrates that both interface fixed charge and interface trap can increase I
off, degrading the off-state performance of device. The study on FBHD-EHBTFET-based dynamic random access memory shows that it has the high read-to-current ratio of 1.1 × 106, high sense margin of 0.42 μA μm−1, and long retention time greater than 100 ms, demonstrating that it has great potential in low-power applications.
Calculation electrical conductivity a two-dimensional electron gas of AlGaN/GaN-based transistors with high electron mobility
Authors: Kuznetsova I A , Romanov D N , Savenko O V
Published: June 2024

An analytical expression of the integral electrical conductivity of a semiconductor nanolayer, the charge carriers of which are located in a triangular quantum well, is obtained. The isoenergetic surface of the semiconductor material has the shape of a triaxial ellipsoid. The charge carrier behavior is described by the quantum Liouville equation. The dependence of electrical conductivity on dimensionless parameters is analyzed: the transverse electric field strength, the longitudinal electric field frequency, the charge carrier effective masses and the heterointerface specular coefficient. It is established that the conductivity of a triangular well compared to a rectangular well is more dependent on the effective mass, which to allow to select a material with the best high-frequency properties.
Theoretical study the photophysical mechanism of fluorescent probe on detecting mitochondria-targeted hydrogen peroxide
Authors: Yuan Haojie , Ding Lina , Liu Yang , Yang Yonggang , Liu Yufang
Published: June 2024

The photophysical mechanism and dynamics behaviors of (E)-4-(2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)vinyl)-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)pyridin-1-ium (Compound 1) on detecting hydrogen peroxide (H2O2) has been theoretically studied. The boron ester in Compound 1 is cleaved when H2O2 is added to the solution, resulting in the formation of (E)-7-(diethylamino)-3-(2-(pyridin-4-yl)vinyl)-2H-chromen-2-one (Compound 2). Theoretical calculations show that the fluorescence spectra of the compounds exhibit a significant blue shift from 616 nm of Compound 1 to 542 nm of Compound 2 before and after the reaction, which are in good agreement with the experimental results (640 nm → 535 nm). The calculated electron–hole transfer distance of Compound 1 (5.986 Å) is larger than that of Compound 2 (3.544 Å), and Compound 1 is demonstrated to be charge transfer excitation while the Compound 2 is localized excitation, which results in a blue shift of the fluorescence spectra. The analysis of molecular electrostatic potential demonstrates that compound 1 has the highest electrostatic potential (4.60 eV) at the pyridine position and the lowest (−0.30 eV) at the oxygen atom of the coumarin moiety, suggesting that compound 1 undergoes fragmentation at this position. This study provides a theoretical explanation for the reaction mechanism of molecular probes.
Hydrothermally synthesized Nb -doped TiO2 nanosheets for efficient removal of methylene blue dye on photocatalytic performance
Authors: Alhashmialameer Dalal , Shariq Mohammad , Althikrallah Hanan A , Al-Amari MM , BaQais Amal , Alayyafi AbdulAziz A , Mergani Ebtihal A , Elghazali Ezdehar A , Elghazali Afaf I , Kumar Bhupender , Assran Awatef S
Published: June 2024

In this work, Niobium-doped (1%, 3%, and 5%) titanium dioxide (Nb-TiO2) nanosheets were successfully formed via the hydrothermal route and further characterized using TEM, XRD, XPS and UV–vis absorption spectroscopy techniques. Phase purity and structural information of the prepared materials were analysed by XRD measurements. The band gap values ranged from 3.27 to 2.98 eV as Nb doping increased, leading to improved photocatalytic activity by creating new energy levels close to the conduction band. The XPS results confirm the amalgamation of Nb5+ ions into TiO2 without affecting the crystallinity, structure or orientation of the occurrence of oxygen vacancies. In 3% Nb-doped TiO2, the degradation efficiency for removing (Methylene blue) MB dye increased by ∼96% for the removal of MB dye within 70 min in comparison to pure and other doped TiO2 catalysts The better photocatalytic activity of 3% Nb-TiO2 is due to the longer time between electron–hole pairs before they recombine into one pair. Hydroxyl radicals (HO•) and superoxide radicals (O2
•−) are the primary reactive entities responsible for the deterioration of MB dye. Therefore, incorporating Nb into TiO2 nanostructures represents an auspicious material for the decomposition of hazardous and toxic pollutants in aquatic environments.
Enhanced electrical parameters of the Au/n-Si Schottky barrier diodes with graphite/graphane oxide doped PVC interlayer
Authors: Taşçıoğlu İ , Badali Y , Altındal Yerişkin S
Published: June 2024

In this work, Schottky Barrier diodes (SBDs) formed on n-Si substrates were created using polyvinyl-chloride (PVC) and graphite/graphene-oxide (Gt/GO) nanoparticles (NPs) doped PVC interlayers and the conduction mechanisms of the structures were compared to the reference Au/n-Si (MS) diode. The characterization methods, including x-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), and Energy Dispersive x-Ray (EDX), were used to analyze Gt/GO NPs and examine their structural, morphological, and analytical properties. In addition to the standard I-V method, modified Norde and Cheung methods were applied to analyze the forward bias I-V characteristics to determine the impact of pure-PVC and (PVC: Gt-GO) interlayers’ main electronic parameters on the SBDs. The surface state density (N

ss
) depending on energy was also determined from the forward bias current–voltage by considering the voltage-dependent ideality coefficient, n(V), and barrier height (BH), ΦB(V). The outcomes showed that, as compared to MS structures, both the pure-PVC and (PVC: Gt-GO) interlayer leads to a decrease of n, leakage-current, N

ss
, an increase of rectification ratio (RR), shunt-resistance (R

sh
) and zero-bias barrier-height (Φ
B0
). The differences in the electronic parameters observed between the I-V, Norde, and Cheung functions indicate that these parameters are highly reliant on the voltage and the computation method utilized. The barrier inhomogeneities at the metal/semiconductor surface also affect the current-transport or conduction mechanisms.
Thermal curvature perturbations in thermal inflation
Authors: Bastero-Gil Mar , M. Gomes Joaquim , G. Rosa João
Published: June 2024

We compute the power spectrum of super-horizon curvature perturbations generated during a late period of thermal inflation, taking into account fluctuation-dissipation effects resulting from the scalar flaton field's interactions with the ambient radiation bath. We find that, at the onset of thermal inflation, the flaton field may reach an equilibrium with the radiation bath even for relatively small coupling constants, maintaining a spectrum of thermal fluctuations until the critical temperature T
c, below which thermal effects stop holding the field at the false potential minimum. This enhances the field variance compared to purely quantum fluctuations, therefore increasing the average energy density during thermal inflation and damping the induced curvature perturbations. In particular, we find that this inhibits the later formation of primordial black holes, at least on scales that leave the horizon for T > T
c. The larger thermal field variance also reduces the duration of a period of fast-roll inflation below T
c, as the field rolls to the true potential minimum, which should also affect the generation of (large) curvature perturbations on even smaller scales.
Regulating the concentration of silica sol to prepare high thermal insulation ceramic nanofiber aerogel composites
Authors: Xu Yuanyuan , Zhang Hao , He Lijuan , Li Wenjing , Liu Yitao
Published: June 2024

Ceramic aerogels can maintain excellent thermal insulation performance under extreme conditions due to their outstanding pore structure and specific surface area. However, the current application of ceramic aerogels is limited by their brittleness, easy collapse of the structure under external forces, and insufficient mechanical properties. In this study, ceramic nanofiber aerogels prepared by PEO as a polymer were used as building blocks, and silica sol was selected as a high-temperature binder. Through the sol impregnation-atmospheric pressure drying method and calcination treatment, we obtained ceramic nanofiber composites with excellent performance. It is found that when the impregnation concentration is 0.4wt%, the thermal conductivity at room temperature is as low as 27 m W·m-1·K-1, the cold surface temperature at 800°C is as low as 255°C, the tensile strength at 20% tensile strain is as high as 400 kPa, and the compressive strength at 80% compressive strain is as high as 32 kPa. Compared with the traditional ceramic fiber aerogel material, the material exhibits excellent high-temperature insulation performance and mechanical properties, which greatly broadens the application scene of ceramic aerogel.
Research on the load-shedding strategy of isolated power grids for regional power grids including wind-hydro power under low-frequency and low-voltage conditions
Authors: Zhang Lei , Wang Mingjin , Zhu Dena , Xiao Ni
Published: June 2024

After more and more wind farms and hydropower plants are connected to the regional power grid, the wind farms and their low-voltage ride-through capabilities of the power grid become increasingly complex. In order to ensure the stable operation of the isolated power grids with wind-hydro power, it is necessary to implement appropriate load-shedding strategies under low-frequency and low-voltage conditions. In this article, we focus on the study of strategies for the operation of district power grids, including wind hydro power, under isolated operation conditions. By combining theoretical analysis with practical considerations, load-shedding strategies are proposed for district power grids under low-frequency and low-voltage. To demonstrate its effectiveness, a simulation model that includes one wind farm and five hydropower plants was conducted to achieve positive results.
Research on safety design of transport packaging for lithium battery products
Authors: Chen Yonghui , Wang Min
Published: June 2024

In view of the characteristics of dangerous goods exported by lithium batteries, the safety norms of lithium battery transport packaging stipulated by international technical regulations are sorted out, and the performance requirements of dangerous goods packaging for export lithium batteries are studied. Based on the overall safety design and protection of this kind of dangerous goods packaging, the design scheme of lithium battery tray protection and carton packaging is proposed. A drop simulation test is carried out to analyze and evaluate the design scheme.
Ion beam stability prediction of ECR ion source based on TCN-DTW network
Authors: Wang R. , Qian C. , Sun L.T. , Guo Y.H. , Cao Z.G. , Hou M.Y.
Published: June 2024

The Electron Cyclotron Resonance (ECR) ion source is an irreplaceable apparatus for producing high-intensity, highly charged heavy ion beams, representing a critical component for heavy ion accelerators. The operation of the ECR ion source is inherently influenced by various factors, leading to fluctuations in beam intensity. Such instability not only diminishes the efficacy of accelerator operations but also introduces distortions in terminal experimental data. Addressing these challenges, this study proposes the application of a Temporal Convolutional Network (TCN) based on a Dynamic Time Warping (DTW) loss function (TCN-DTW) for predicting the stability of the ion beams. Prior to constructing the prediction network, raw data undergoes preprocessing through an Interquartile Range (IQR) anomaly detection mechanism and the Savitzky-Golay (SG) filtering algorithm with an adaptive window. Experimental results demonstrate a substantial enhancement in prediction performance when employing the TCN network with the DTW loss function compared to traditional alternatives. This approach facilitates effective forecasting of the ion source beam current trend, offering a basis for the control and correction of long-term stability. Consequently, it provides valuable insights for optimizing the ECR ion source and enhancing overall accelerator operational performance.
Harnessing extracellular vesicles-mediated signaling for enhanced bone regeneration: novel insights into scaffold design
Authors: Kanniyappan Hemalatha , Gnanasekar Varun , Parise Vincent , Debnath Koushik , Sun Yani , Thakur Shriya , Thakur Gitika , Perumal Govindaraj , Kumar Raj , Wang Rong , Merchant Aftab , Sriram Ravindran , Mathew Mathew T
Published: June 2024

The increasing prevalence of bone replacements and complications associated with bone replacement procedures underscores the need for innovative tissue restoration approaches. Existing synthetic grafts cannot fully replicate bone vascularization and mechanical characteristics. This study introduces a novel strategy utilizing pectin, chitosan, and polyvinyl alcohol to create interpenetrating polymeric network (IPN) scaffolds incorporated with extracellular vesicles (EVs) isolated from human mesenchymal stem cells (hMSCs). We assess the osteointegration and osteoconduction abilities of these models in vitro using hMSCs and MG-63 osteosarcoma cells. Additionally, we confirm exosome properties through Transmission Electron Microscopy (TEM), immunoblotting, and Dynamic Light Scattering (DLS). In vivo, chick allantoic membrane assay investigates vascularization characteristics. The study did not include in vivo animal experiments. Our results demonstrate that the IPN scaffold is highly porous and interconnected, potentially suitable for bone implants. EVs, approximately 100 nm in size, enhance cell survival, proliferation, alkaline phosphatase activity, and the expression of osteogenic genes. EVs-mediated IPN scaffolds demonstrate promise as precise drug carriers, enabling customized treatments for bone-related conditions and regeneration efforts. Therefore, the EVs-mediated IPN scaffolds demonstrate promise as precise carriers for the transport of drugs, allowing for customized treatments for conditions connected to bone and efforts in regeneration.
Spacing distribution for quantum Rabi models
*
Authors: Thi Hoai Nguyen Linh , Reyes-Bustos Cid , Braak Daniel , Wakayama Masato
Published: June 2024

The asymmetric quantum Rabi model (AQRM) is a fundamental model in quantum optics describing the interaction of light and matter. Besides its immediate physical interest, the AQRM possesses an intriguing mathematical structure which is far from being completely understood. In this paper, we focus on the distribution of the level spacing, the difference between consecutive eigenvalues of the AQRM in the limit of high energies, i.e. large quantum numbers. In the symmetric case, that is the quantum Rabi model (QRM), the spacing distribution for each parity (given by the

Z

2

-symmetry) is fully clarified by an asymptotic expression derived by de Monvel and Zielinski, though some questions remain for the full spectrum spacing. However, in the general AQRM case, there is no parity decomposition for the eigenvalues. In connection with numerically exact studies and recent theoretical results, we describe the spacing distribution for the AQRM which is characterized by a new type of periodicity and symmetric behavior of the distribution with respect to the bias parameter, reflecting the hidden symmetry of the AQRM. In addition, we observe in the AQRM the excited state quantum phase transition for large values of the bias parameter, analogous to the QRM with large qubit energy, and an internal symmetry of the level spacing distribution for fixed bias. This novel symmetry is independent from the symmetry for half-integer bias and not explained by current theoretical knowledge.
Gauge reduction in covariant field theory
Authors: Castrillón López Marco , Rodríguez Abella Álvaro
Published: June 2024

In this work, we develop a Lagrangian reduction theory for covariant field theories with gauge symmetries. These symmetries are modeled by a Lie group fiber bundle acting fiberwisely on a configuration bundle. In order to reduce the variational principle, we utilize generalized principal connections, a type of Ehresmann connections that are equivariant by the fiberwise action. After obtaining the reduced equations, we give the reconstruction condition and we relate the vertical reduced equation with the Noether theorem. Lastly, we illustrate the theory with several examples, including the classical case (Lagrange–Poincaré reduction), Electromagnetism, symmetry-breaking and non-Abelian gauge theories.
Entanglement and correlations in an exactly-solvable model of a Bose–Einstein condensate in a cavity
Authors: Alon Ofir E , Cederbaum Lorenz S
Published: June 2024

An exactly solvable model of a trapped interacting Bose–Einstein condensate (BEC) coupled in the dipole approximation to a quantized light mode in a cavity is presented. The model can be seen as a generalization of the harmonic-interaction model for a trapped BEC coupled to a bosonic bath. After obtaining the ground-state energy and wavefunction in closed form, we focus on computing the correlations in the system. The reduced one-particle density matrices of the bosons and the cavity are constructed and diagonalized analytically, and the von Neumann entanglement entropy of the BEC and the cavity is also expressed explicitly as a function of the number and mass of the bosons, frequencies of the trap and cavity, and the cavity-boson coupling strength. The results allow one to study the impact of the cavity on the bosons and vice versa on an equal footing. As an application we investigate a specific case of basic interest for itself, namely, non-interacting bosons in a cavity. We find that both the bosons and the cavity develop correlations in a complementary manner while increasing the coupling between them. Whereas the cavity wavepacket broadens in Fock space, the BEC density saturates in real space. On the other hand, while the cavity depletion saturates, and hence does the BEC-cavity entanglement entropy, the BEC becomes strongly correlated and eventually increasingly fragmented. The latter phenomenon implies single-trap fragmentation of otherwise ideal bosons, where their induced long-range interaction is mediated by the cavity. Finally, as a complimentary investigation, the mean-field equations for the BEC-cavity system are solved analytically as well, and the breakdown of mean-field theory for the cavity and the bosons with increasing coupling is discussed. Further applications are envisaged.
Advances in magnetic-assisted triboelectric nanogenerators: structures, materials and self-sensing systems
Authors: Wu Pengfan , Zhao Chenxi , Cui Endian , Xu Shiwei , Liu Tao , Wang Fayang , Lee Chengkuo , Mu Xiaojing
Published: June 2024

Triboelectric nanogenerators (TENG), renowned for their remarkable capability to harness weak mechanical energy from the environment, have gained considerable attention owing to their cost-effectiveness, high output, and adaptability. This review provides a unique perspective by conducting a comprehensive and in-depth analysis of magnetically assisted TENGs that encompass structures, materials, and self-powered sensing systems. We systematically summarize the diverse functions of the magnetic assistance for TENGs, including system stiffness, components of the hybrid electromagnetic-triboelectric generator, transmission, and interaction forces. In the material domain, we review the incorporation of magnetic nano-composites materials, along with ferrofluid-based TENG and microstructure verification, which have also been summarized based on existing research. Furthermore, we delve into the research progress on physical quantity sensing and human-machine interface in magnetic-assisted TENGs. Our analysis highlights that magnetic assistance extends beyond the repulsive and suction forces under a magnetic field, thereby playing multifaceted roles in improving the output performance and environmental adaptability of the TENGs. Finally, we present the prevailing challenges and offer insights into the future trajectory of the magnetic-assisted TENGs development.
AMCG: a graph dual atomic-molecular conditional molecular generator
Authors: Abate Carlo , Decherchi Sergio , Cavalli Andrea
Published: June 2024

Drug design is both a time consuming and expensive endeavour. Computational strategies offer viable options to address this task; deep learning approaches in particular are indeed gaining traction for their capability of dealing with chemical structures. A straightforward way to represent such structures is via their molecular graph, which in turn can be naturally processed by graph neural networks. This paper introduces AMCG, a dual atomic-molecular, conditional, latent-space, generative model built around graph processing layers able to support both unconditional and conditional molecular graph generation. Among other features, AMCG is a one-shot model allowing for fast sampling, explicit atomic type histogram assignation and property optimization via gradient ascent. The model was trained on the Quantum Machines 9 (QM9) and ZINC datasets, achieving state-of-the-art performances. Together with classic benchmarks, AMCG was also tested by generating large-scale sampled sets, showing robustness in terms of sustainable throughput of valid, novel and unique molecules.
Preclinical studies of BB-1701, a HER2-targeting eribulin-containing ADC with potent bystander effect and ICD activity
Authors: Wang Yang , Xia Bing , Cao Lixia , Yang Jianfeng , Feng Cui , Jiang Fangdun , Li Chen , Gu Lixia , Yang Yifan , Tian Jing , Cheng Xin , Furuuchi Keiji , Fulmer James , Verdi Arielle , Rybinski Katherine , Soto Allis , Albone Earl , Uenaka Toshimitsu , Gong Likun , Liu Tingting , Qin Qiuping , Wei Ziping , Zhou Yuhong
Published: June 2024

Background: Several HER2-targeting antibody–drug conjugates (ADC) have gained market approval for the treatment of HER2-expressing metastasis. Promising responses have been reported with the new generation of ADCs in patients who do not respond well to other HER2-targeting therapeutics. However, these ADCs still face challenges of resistance and/or severe adverse effects associated with their particular payload toxins. Eribulin, a therapeutic agent for the treatment of metastatic breast cancer and liposarcoma, is a new choice of ADC payload with a distinct mechanism of action and safety profile. Methods: We’ve generated a novel HER2-tageting eribulin-containing ADC, BB-1701. The potency of BB-1701 was tested in vitro and in vivo against cancer cells where HER2-expressing levels vary in a large range. Bystander killing effect and toxin-induced immunogenic cell death (ICD) of BB-1701 were also tested. Results: In comparison with HER2-targeting ADCs with DM1 and Dxd payload, eribulin-containing ADC demonstrated higher in vitro cytotoxicity in HER2-low cancer cell lines. BB-1701 also effectively suppressed tumors in models resistant to DM1 or Dxd containing ADCs. Mode of action studies showed that BB-1701 had a significant bystander effect on HER2-null cells adjacent to HER2-high cells. In addition, BB-1701 treatment induced ICD. Repeated doses of BB-1701 in nonhuman primates showed favorable pharmacokinetics and safety profiles at the intended clinical dosage, route of administration, and schedule. Conclusions: The preclinical data support the test of BB-1701 in patients with various HER2-expressing cancers, including those resistant to other HER2-targeting ADCs. A phase I clinical trial of BB-1701 (NCT04257110) in patients is currently underway.
Role of the Anaphylatoxin Receptor C5aR2 in Angiotensin II-Induced Hypertension and Hypertensive End-Organ Damage
Authors: Dreher Leonie , Bode Marlies , Ehnert Nicolas , Meyer-Schwesinger Catherine , Wiech Thorsten , Köhl Jörg , Huber Tobias B , Freiwald Tilo , Herrnstadt Georg R , Wenzel Ulrich O
Published: June 2024

BACKROUND

Complement activation may facilitate hypertension through its effects on immune responses. The anaphylatoxin C5a, a major inflammatory effector, binds to the C5a receptors 1 and 2 (C5aR1, C5aR2). We have recently shown that C5aR1−/− mice have reduced hypertensive renal injury. The role of C5aR2 in hypertension is unknown.

METHODS

For examination of C5aR2 expression on infiltrating and resident renal cells a tandem dye Tomato-C5aR2 knock-in reporter mouse was used. Human C5aR2 expression was analyzed in a single-cell RNAseq data set from the kidneys of hypertensive patients. Finally, we examined the effect of angiotensin II-induced hypertension in C5aR2-deficient mice.

RESULTS

Flow cytometric analysis of leukocytes isolated from kidneys of the reporter mice showed that dendritic cells are the major C5aR2-expressing population (34%) followed by monocyte/macrophages (30%) and neutrophils (14%). Using confocal microscopy C5aR2 was not detected in resident renal or cardiac cells. In the human kidney, C5aR2 was also mainly found in monocytes, macrophages, and dendritic cells with a significantly higher expression in hypertension (P < 0.05). Unilateral nephrectomy was performed followed by infusion of Ang II (0.75 ng/g/min) and a high salt diet in wildtype (n = 18) and C5aR2-deficient mice (n = 14). Blood pressure, renal injury (albuminuria, glomerular filtration rate, glomerular and tubulointerstitial injury, inflammation), and cardiac injury (cardiac fibrosis, heart weight, gene expression) did not differ between hypertensive wildtype and C5aR2−/− mice.

CONCLUSIONS

In summary, C5aR2 is mainly expressed in myeloid cells in the kidney in mice and humans but its deficiency has no effect on Ang II-induced hypertensive injury.
Protein interaction explorer (PIE): a comprehensive platform for navigating protein–protein interactions and ligand binding pockets
Authors: Mareuil Fabien , Moine-Franel Alexandra , Kar Anuradha , Nilges Michael , Ciambur Constantin Bogdan , Sperandio Olivier
Published: June 2024

Protein Interaction Explorer (PIE) is a new web-based tool integrated to our database iPPI-DB, specifically crafted to support structure-based drug discovery initiatives focused on protein–protein interactions (PPIs). Drawing upon extensive structural data encompassing thousands of heterodimer complexes, including those with successful ligands, PIE provides a comprehensive suite of tools dedicated to aid decision-making in PPI drug discovery. PIE enables researchers/bioinformaticians to identify and characterize crucial factors such as the presence of binding pockets or functional binding sites at the interface, predicting hot spots, and foreseeing similar protein-embedded pockets for potential repurposing efforts.

Availability and implementation

PIE is user-friendly and readily accessible at https://ippidb.pasteur.fr/targetcentric/. It relies on the NGL visualizer.
Estrogen to progesterone ratio is associated with conceptus attachment in dairy cows receiving artificial insemination after Double-Ovsynch but not estrus
Authors: Minela Thainá , Santos Alisson , Pursley J Richard
Published: June 2024

Prediction of pregnancy survival in lactating dairy cows can be determined by the conceptus attachment timeframe via daily pregnancy-specific protein B (PSPB) monitoring. All factors contributing to reduced fertility in dairy cows receiving AI following estrus detection remain unclear. This study aimed to determine differences in time to conceptus attachment in lactating cows treated with the fertility program Double-Ovsynch compared to cows that were detected in estrus. Additionally, we investigated various pre- and post-conception factors potentially influencing fertility outcomes. We hypothesized that AI following a natural estrus detected with automated activity monitors would lead to an extended time to conceptus attachment and lower PSPB concentrations post-attachment compared to Double-Ovsynch. There were no differences in the average time to conceptus attachments between treatments. However, cows inseminated post-estrus that experienced pregnancy loss between conceptus attachment and 60–66 days post-AI exhibited diminished PSPB concentrations on Days 2 and 3 following conceptus attachment. Steroid hormone interactions were assessed with radioimmunoassay to determine the ratios of estrogen to progesterone concentrations on the day of the luteinizing hormone (LH) surge. Notably, estrogen to progesterone ratio proved to predict conceptus attachment in cows subjected to Double-Ovsynch but not in those inseminated post-estrus detection surge. In conclusion, the estrogen to progesterone ratio measured around the time of the pre-ovulatory LH surge emerges as a potentially effective tool for estimating the fertility potential of lactating dairy cows undergoing timed AI, particularly in the context of the Double-Ovsynch program.
A preliminary study of super-resolution deep learning reconstruction with cardiac option for evaluation of endovascular-treated intracranial aneurysms
Authors: Otgonbaatar Chuluunbaatar , Kim Hyunjung , Jeon Pil-Hyun , Jeon Sang-Hyun , Cha Sung-Jin , Ryu Jae-Kyun , Jung Won Beom , Shim Hackjoon , Ko Sung Min , Kim Jin Woo
Published: June 2024

Objectives

To investigate the usefulness of super-resolution deep learning reconstruction (SR-DLR) with cardiac option in the assessment of image quality in patients with stent-assisted coil embolization, coil embolization, and flow-diverting stent placement compared with other image reconstructions.

Methods

This single-centre retrospective study included 50 patients (mean age, 59 years; range, 44-81 years; 13 men) who were treated with stent-assisted coil embolization, coil embolization, and flow-diverting stent placement between January and July 2023. The images were reconstructed using filtered back projection (FBP), hybrid iterative reconstruction (IR), and SR-DLR. The objective image analysis included image noise in the Hounsfield unit (HU), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and full width at half maximum (FWHM). Subjectively, two radiologists evaluated the overall image quality for the visualization of the flow-diverting stent, coil, and stent.

Results

The image noise in HU in SR-DLR was 6.99 ± 1.49, which was significantly lower than that in images reconstructed with FBP (12.32 ± 3.01) and hybrid IR (8.63 ± 2.12) (P < .001). Both the mean SNR and CNR were significantly higher in SR-DLR than in FBP and hybrid IR (P < .001 and P < .001). The FWHMs for the stent (P < .004), flow-diverting stent (P < .001), and coil (P < .001) were significantly lower in SR-DLR than in FBP and hybrid IR. The subjective visual scores were significantly higher in SR-DLR than in other image reconstructions (P < .001).

Conclusions

SR-DLR with cardiac option is useful for follow-up imaging in stent-assisted coil embolization and flow-diverting stent placement in terms of lower image noise, higher SNR and CNR, superior subjective image analysis, and less blooming artifact than other image reconstructions.

Advances in knowledge

SR-DLR with cardiac option allows better visualization of the peripheral and smaller cerebral arteries. SR-DLR with cardiac option can be beneficial for CT imaging of stent-assisted coil embolization and flow-diverting stent.
Development of an ontology for laparoscopic transabdominal adrenalectomy via a comprehensive modified Delphi survey and its validation on a multicentric pilot data set for surgical training and future video analysis with machine learning algorithms
Authors: Seeliger Barbara , Di Lorenzo Sofia , Alesina Pier F , Brunaud Laurent , Chiapponi Costanza , De Crea Carmela , Donatini Gianluca , Iacobone Maurizio , Makay Özer , Mihai Radu , Mogl Martina T , Mutter Didier , Padoy Nicolas , Palazzo Fausto , Vidal Oscar , Pennestrí Francesco , Marescaux Jacques , Vix Michel , Raffaelli Marco
Published: June 2024

Lay Summary

Surgical technique is essential to ensure safe minimally invasive adrenalectomy. Due to the relative rarity of adrenal surgery, it is challenging to ensure adequate exposure in surgical training. Surgical video analysis supports auto-evaluation, expert assessment and could be a target for automatization. The developed ontology was validated by a European expert consensus and is applicable across the surgical techniques encountered in all participating centres, with an exemplary demonstration in bi-centric recordings. Standardization of adrenalectomy video analysis may foster surgical training and enable machine learning training for automated safety alerts.
Threshold of somatic mosaicism leading to brain dysfunction with focal epilepsy
Authors: Kim Jintae , Park Sang Min , Koh Hyun Yong , Ko Ara , Kang Hoon-Chul , Chang Won Seok , Kim Dong Seok , Lee Jeong Ho
Published: June 2024

Somatic mosaicism in a fraction of brain cells causes neurodevelopmental disorders, including childhood intractable epilepsy. However, the threshold for somatic mosaicism leading to brain dysfunction is unknown. In this study, we induced various mosaic burdens in focal cortical dysplasia type II (FCD II) mice, featuring mTOR somatic mosaicism and spontaneous behavioural seizures.

The mosaic burdens ranged from approximately 1000 to 40 000 neurons expressing the mTOR mutant in the somatosensory or medial prefrontal cortex. Surprisingly, approximately 8000–9000 neurons expressing the MTOR mutant, extrapolated to constitute 0.08%–0.09% of total cells or roughly 0.04% of variant allele frequency in the mouse hemicortex, were sufficient to trigger epileptic seizures. The mutational burden was correlated with seizure frequency and onset, with a higher tendency for electrographic inter-ictal spikes and beta- and gamma-frequency oscillations in FCD II mice exceeding the threshold. Moreover, mutation-negative FCD II patients in deep sequencing of their bulky brain tissues revealed somatic mosaicism of the mTOR pathway genes as low as 0.07% in resected brain tissues through ultra-deep targeted sequencing (up to 20 million reads). Thus, our study suggests that extremely low levels of somatic mosaicism can contribute to brain dysfunction.
Community resilience through bottom–up participation: when civil society drives urban transformation processes
Authors: Kirby Nicolina , Stasiak Dorota , von Schneidemesser Dirk
Published: June 2024

In recent years, bottom–up civil society initiatives have advanced urban transformation processes in Berlin. Following previous research suggesting that bottom–up participation could have a positive impact on community resilience (CR), we analyse the impact of engagement on Berlin–based civil society initiatives. Whilst a positive effect on resilience can be found, we identify governance processes that would be necessary to enable the full potential of bottom–up participation for CR. Resilience, understood as the capacity of a community to thrive in times of change and uncertainty, is becoming increasingly important for the functioning of (urban) communities; hence, finding ways of strengthening it is deemed necessary.
Nickel-photoredox-catalyzed E- and Z-stereoconvergent coupling of alkenyl halides and phenols
Authors: Nishino Sodai , Kurahashi Takuya
Published: June 2024

Herein, we report a Ni-photoredox-catalyzed stereoconvergent coupling of phenols and alkenyl halides, which affords a Z-coupling product. Moreover, by simply changing the solvent, the reaction also provides access to the E-coupling product with high stereoselectivity. The key factor for changing the stereoisomer of the product was found to be the fluorescence lifetime of photocatalyst.