bluuebunny/crossref_metadata_2025 huggingface dataset:
Reconstruction of the turbulent flow field with sparse measurements using physics-informed neural network
Authors: Chaurasia Nagendra Kumar , Chakraborty Shubhankar
Published: August 2024

Accurate high-resolution flow field prediction based on limited experimental data is a complex task. This research introduces an innovative framework leveraging physics-informed neural network (PINN) to reconstruct high-resolution flow fields using sparse particle image velocimetry measurements for flow over a periodic hill and high-fidelity computational fluid dynamics data for flow over a curved backward-facing step. Model training utilized mean flow measurements, with increased measurement sparsity achieved through various curation strategies. The resulting flow field reconstruction demonstrated marginal error in both test cases, showcasing the ability of the framework to reconstruct the flow field with limited measurement data accurately. Additionally, the study successfully predicted flow fields under two different noise levels, closely aligning with experimental and high-fidelity results (experimental, direct numerical simulation, or large eddy simulation) for both cases. Hyperparameter tuning conducted on the periodic hill case has been applied to the curved backward-facing step case. This research underscores the potential of PINN as an emerging method for turbulent flow field prediction via data assimilation, offering reduced computational costs even with sparse, noisy measurements.
Experimental study on the interaction between particles and coherent structures in dilute liquid–solid two-phase turbulent boundary layer
Authors: Gao Tian-da , Sun Jiao , Sun Kang-fu , Yuan Peng-da , Yu Lin-meng , Chen Wen-yi
Published: August 2024

In order to reveal the modulation of particles on turbulent coherent structures and particle concentration variations induced by turbulence, particle image velocimetry experiments were performed in a dilute liquid–solid two-phase turbulent boundary layer. Large-scale coherent structures, including streaks and hairpin vortices, were extracted in the liquid–solid two-phase turbulent boundary layer by using multiple methods, such as proper orthogonal decomposition and finite-time Lyapunov exponent. The results showed that the addition of particles thickened the buffer layer of the average velocity profile, weakened the streamwise turbulence intensity at y+ > 10, strengthened the wall-normal turbulence in the near wall region (y+ < 52), and weakened the Reynolds stress in the logarithmic law region. A more thorough study of the turbulent structure revealed that the particles caused the mean spacing of the near-wall streak structure to increase, hairpin vortex migration to slow down, the uplift of hairpin vortex to be suppressed, and the overall size of the hairpin vortex packet to be compressed. This demonstrated that particles could modulate turbulence by inhibiting the development of hairpin vortices.
Temperature effects on neuronal synchronization in seizures
Authors: Follmann Rosangela , Jaswal Twinkle , Jacob George , de Oliveira Jonas Ferreira , Herbert Carter B. , Macau Elbert E. N. , Rosa Epaminondas
Published: August 2024

We present a computational model of networked neurons developed to study the effect of temperature on neuronal synchronization in the brain in association with seizures. The network consists of a set of chaotic bursting neurons surrounding a core tonic neuron in a square lattice with periodic boundary conditions. Each neuron is reciprocally coupled to its four nearest neighbors via temperature dependent gap junctions. Incorporating temperature in the gap junctions makes the coupling stronger when temperature rises, resulting in higher likelihood for synchrony in the network. Raising the temperature eventually makes the network elicit waves of synchronization in circular ripples that propagate from the center outwardly. We suggest this process as a possible underlying mechanism for seizures induced by elevated brain temperatures.
Bioinspired swept-curved blade design for performance enhancement of Darrieus wind turbine
Authors: Prakash P. , Laws P. , Mitra S. , Mishra N.
Published: August 2024

The present research proposes novel swept-curved bioinspired blades for Darrieus wind turbine. The design was influenced by the curved flippers of the bottle-nose dolphin. The proposed model was designed using the Solidworks software, empirically tested for power improvement, later fine-tuned adopting high fidelity numerical modeling. An in-depth analysis comparing the traditional H-bladed turbine with the new-bladed design was performed using OpenFOAM. Further, an elaborate experimental observations on the proposed design suggest that the model with 0.6c forward sweep outperformed the rest. The efficiency of the curved blade was notably enhanced by 14.41%, in contrast to the conventional model, and the numerical analysis endorses this observation. The modified turbine blades have the maximum wind streamlines that converge toward the center of the blade's trailing edge due to the lateral shift, and the resulting convergence reduces blade tip losses. The modified blade models demonstrated improved angular acceleration at a given wind speed, indicating enhanced efficiency and superior self-starting capabilities. Notably, these improvements were evident even at a lower wind speed of 4.2 m/s compared to the traditional H-model.
Effect of free and compound vortex designs on the energy characteristics and operational stability of mixed flow pumps
Authors: Wang Mengcheng , Chen Songshan , Gu Yandong , Yang Yang , Xia Zhufeng , Chen Jiaqi
Published: August 2024

The effectiveness of the inverse design method has been widely proven in previous studies, but research on the effect of different vortex designs on the performance of mixed flow pumps is relatively scarce. In this paper, the performances of models I1 and I2, which were designed with free and compound vortex designs, respectively, are compared to study the effect of different vortex designs on the energy characteristics and operational stability of mixed flow pumps. The results show that the efficiency of the compound vortex design at 0.8Qdes, 1.0Qdes, and 1.2Qdes is improved by 0.54%, 0.95%, and 5.91%, respectively, compared to that of the free vortex design, and the velocity and pressure pulsations under the design conditions are also significantly reduced. The internal flow analysis shows that the increased efficiency in the compound vortex design is mainly related to the reduction in the local entropy production from the hub to the mid-span and the wall entropy production from the mid-span to the shroud within the diffuser due to the improvement in the jet-wake structure near the hub. The increased operational stability is mainly related to the suppression of low-momentum fluid aggregation and H-S secondary flow caused by the increase in axial velocity near the hub and the spanwise uniformity of the total pressure.
NIR-II femtosecond laser-induced nonlinear absorption facilitates foreground-extraction photoacoustic imaging by monolayer WS2-PVP nanosheets
Authors: Liu Xiaowan , Cui Dandan , Shang Xuyan , Liu Yuning , Wang Yikai , Shi Yujiao
Published: August 2024

Exogenous contrast agents have been extensively applied in photoacoustic (PA) molecular imaging for disease diagnosis, benefiting from their advantageous optical, thermal, and internal delivery properties. However, their in vivo performance was inevitably interfered by background tissue optical absorption, resulting in low imaging contrast and sensitivity. Here, we report a NIR-II femtosecond laser-induced nonlinearly enhanced PA imaging technique based on two-photon absorption of monolayer WS2-PVP nanosheets (NSs), which facilitates foreground extraction of the targeting region with the background signal being significantly suppressed. The optical nonlinearity of the monolayer WS2-PVP NSs was first demonstrated by a Z-scan system under the irradiation of a femtosecond laser to be 0.38, with an antithesis of virtually zero for the tissue-mimicking sample. Experiments on tissue-mimicking phantoms and in vitro chicken breast showed that the nonlinear PA enhancement of monolayer WS2-PVP NSs can facilitate foreground-extraction imaging at deep-seated position up to 4 mm. In addition, the in vivo foreground-extraction imaging ability by using monolayer WS2-PVP NSs was further demonstrated by mouse tumor models, where the tumor regions were specifically extracted with high imaging contrast. This work proposed a nonlinearly enhanced contrast mechanism of PA nanoprobes, prefiguring great potential for high-contrast and high-specificity PA molecular imaging.
Photoexcitation and recombination processes of the neutral nitrogen-vacancy center in diamond from first principles
Authors: Thiering Gergő , Gali Adam
Published: August 2024

Nitrogen-vacancy (NV) complex in diamond is one of the most prominent solid state defects as the negatively charged NV defect (NV−) is a leading contender for quantum technologies. In quantum information processing applications, NV− is photoexcited that often leads to photoionization to neutral NV defect, NV0, and re-ionization back to NV− should occur to control the S=1 spin of NV−. As a consequence, understanding the photophysics of NV0 is crucial for controlling NV−. Furthermore, recent studies have shown that the S=1/2 electron spin of NV0 can also be initialized and read out at certain conditions that turns single NV0 a potential quantum bit. Quantum optics protocols rest on detailed knowledge on the electronic structure of the given system, which is obviously missing for NV0 in diamond. In this study, we combine the group theory and density functional theory calculations toward exploring the nature of the ground and excited states of NV0. We show that the effective three-electron system of NV0 leads to high correlation effects that make this system very challenging for ab initio simulations.
Inverted V-shaped size-dependent emission wavelength shift in InGaN micro-LEDs with size down to 1 μm
Authors: Liu Bo , Sun Chenyang , Yu Luming , Hao Zhibiao , Luo Yi , Sun Changzheng , Xiong Bing , Han Yanjun , Wang Jian , Li Hongtao , Gan Lin , Wang Lai
Published: August 2024

The size-dependent emission wavelength shift of micro-scale light emitting diodes (micro-LEDs) has been frequently reported in recent publications, but its underlying physical mechanism has not yet been thoroughly elucidated. Here, we fabricate and characterize the red, green, and blue InGaN micro-LED mesas with different diameters down to 1 μm. As the size decreases, all the samples of different colors show an inverted V-shaped photoluminescence wavelength variation trend, first a red shift and then a blue shift, and the shifting range is larger for samples with longer wavelengths. Micro-Raman spectrum confirms that the stress was significantly released after scaling down the size from epitaxial wafer to 1 μm. The theoretical simulations show that the red and blue shifts are, respectively, attributed to the bandgap narrowing and the weakening of the quantum-confined Stark effect caused by strain relaxation, which dominate successively.
Transverse magneto-optical Kerr effect enhanced by surface plasmon resonances at the critical coupling condition
Authors: Zhang Pengsen , Li Lixia , Zong Xueyang , Cui Lin , Lei Fugui , Liu Yufang
Published: August 2024

Nanostructures possessing plasmonic and magnetic properties can enhance the transverse magneto-optical Kerr effect (TMOKE) by exciting surface plasmon resonances (SPRs). This provides a promising platform for magneto-optical SPR sensors with significantly improved sensing performance. Here, we propose a high-performance magneto-optical SPR sensor, which consists of a bilayer Au/Co grating placed on a gold film. By tuning the structural parameters, a Fano-like TMOKE spectrum with a linewidth of only 0.0135 nm and an amplitude approaching the theoretical maximum is obtained. We attribute the optimal TMOKE signal achieved by the sensor to the critical coupling concept which is associated with the trade-off between scattering and intrinsic decay rates of the system. The optimized nanostructure sensor demonstrates a sensitivity of 1432 nm/RIU to refractive index fluctuations as small as 0.0001 in air, and all figures of merit (FOM) up to 105 RIU−1, making it suitable for gas sensor fabrication.
Temperature and pressure jump coefficients at a liquid–vapor interface
Authors: Kalempa Denize , Graur Irina
Published: August 2024

The temperature and pressure jump coefficients at a liquid–vapor interface are calculated from the solution of the Shakhov kinetic model for the linearized Boltzmann equation. Complete and partial evaporation/condensation at the vapor–liquid interface are assumed as the boundary condition. The discrete velocity method is used to solve the problem numerically. The jump coefficients are tabulated as functions of the evaporation/condensation coefficient. The profiles of the vapor temperature and pressure deviations from that values at the interface corresponding to the liquid temperature and saturation pressure are plotted, and the solutions obtained from kinetic theory and continuum approach are shown to underline the effect of the jumps at the interface. The obtained results have been compared to those given by other authors, who applied the linearized Boltzmann equation as well as the model proposed by Bhatnagar, Gross, and Krook to it, and it was found that the pressure and temperature jump coefficients are relatively insensitive to the collision laws.
Kinetics-controlled epitaxial growth and bipolar transport properties of semimetal Bi4Se3
Authors: Li Junye , Ji Haining , Wang Jianwei , Li Handong , Niu Xiaobin , Wang Zhiming M.
Published: August 2024

(Bi2)m(Bi2Se3)n (m, n: integers) compounds with an infinitely adaptive superlattice structure exhibit several fascinating topological phases. Here, we study kinetics-controlled epitaxial growth of Bi4Se3 on mica by co-evaporating Bi and Se using molecular beam epitaxy technique, as well as the transport properties of Bi4Se3. By precisely controlling the beam fluxes of Bi and Se and growth temperature, we can tune the growth modes from van der Waals' condensation to spiral growth, thus achieving single-crystalline Bi4Se3 of dislocation-free microplate or mounded thin-film morphologies. This reflects a transition from near-thermodynamic-equilibrium to non-thermodynamic-equilibrium growth processes of single-crystalline Bi4Se3. Thin-film Bi2+xSe3 (1.7 < x < 2) solid-solution phases consisting of randomly stacked Bi2 and Bi2Se3 units are also prepared as comparative samples. Hall and thermopower properties suggest that the as-grown Bi4Se3 films exhibit semimetallic bipolar conduction behaviors while the Bi2+xSe3 films present typical semiconducting transport characteristics with a n-type polarity. Due to semiconductor band structures, the Bi2+xSe3 films show superior thermopower to that of semimetal Bi4Se3.
Spatiotemporal flow-induced instability of predator–prey model with Crowley–Martin functional response and prey harvesting
Authors: Bhunia Bidhan , Kumar Kar Tapan , Ghorai Santu
Published: August 2024

Ecological systems can generate striking large-scale spatial patterns through local interactions and migration. In the presence of diffusion and advection, this work examines the formation of flow-induced patterns in a predator–prey system with a Crowley–Martin functional response and prey harvesting, where the advection reflects the unidirectional flow of each species migration (or flow). Primarily, the impact of diffusion and advection rates on the stability and the associated Turing and flow-induced patterns are investigated. The theoretical implication of flow-induced instability caused by population migration, mainly the relative migrations between prey and predator, is examined, and it also shows that Turing instability is the particular condition of flow-induced instability. The influence of the relative flow of both species and prey-harvesting effort on the emerging pattern is reported. Advection impacts a wide range of spatiotemporal patterns, including bands, spots, and a mixture of bands and spots in both harvested and unharvested dynamics. We also observe the diagonally bend-type banded patterns and straight-type banded patterns due to positive and negative relative flows, respectively. Here, the increasing relative flow increases the band length. The growing harvesting effort also decreases the band length, producing a thin band and a mixture of spots and bands due to the negative and positive relative flows, respectively. One exciting result observed here is that harvesting effort drives the flow-Turing and flow-Turing–Hopf instability into pure-flow instability.
Distinguishing the impact of oxidation on the Josephson junction oxide barrier through the 1/f behavior
Authors: Chen Yong , Duan Peng , Jia Zhi-Long , Yang Xin-Xin , Du Lei , Tao Hao-Ran , Zhang Chi , Guo Liang-Liang , Zhang Hai-Feng , Wang Tian-Le , Zhao Ze-An , Yang Xiao-Yan , Zhang Sheng , Zhao Ren-Ze , Wang Peng , Kong Wei-Cheng , Guo Guo-Ping
Published: August 2024

The quality of the oxide barrier in Josephson junctions (JJs) is crucial for devices with it as the core structure. Despite the critical nature of the oxidation process in JJ fabrication, there remains a lack of systematic research on its impact. Our study aims to fill this gap by comprehensively investigating the influence of oxidation parameters and methods on the oxide barrier quality. To achieve this, we evaluate the low-frequency 1/f noise of JJs produced using various fabrication processes. Our findings demonstrate that a weak oxidation strength (oxygen pressure × exposure time) and a dynamic oxidation method contribute positively to the formation of high-quality oxide barriers. This research provides an important reference for optimizing the oxidation process.
Revisiting the governing equations of a magnetic suspension of polar particles: From microhydrodynamics analysis to rheological response
Authors: Cunha F. R. , Gontijo R. G.
Published: August 2024

In this review, we describe a formulation for the stress tensor of a monodisperse magnetic suspension of polarized neutrally buoyant spheroidal particles suspended in a non-magnetic liquid. A magnetic suspension affords a rare example of a material for which the stress tensor is non-symmetric. The present formulation is based on a microhydrodynamics description of a spherical particle suspended in a Newtonian fluid subjected to magnetic forces and torques. The magnetic suspension is considered statistically homogeneous and treated as being a homogeneous equivalent fluid. Under this condition, a volume average over all particles in the carrier fluid is used in order to obtain the magnetization equation evolution and the constitutive equation for the stress tensor of the magnetic suspension, in particular the magnetic stress contribution. The average effects on the homogeneous continuum fluid due to particle pressure, particle dipole, and the applied magnetic field on each particle are computed by our constitutive equation. In this approach, the particles are not considered force or torque free since their permanent magnetization allows them to experience the effects of an applied magnetic field. The calculated stress tension can be used for modeling common flows of symmetric or non-symmetric magnetic fluids flowing in arbitrary geometries and in rheological applications for determination of important properties such as the rotational viscosity of non-symmetric magnetic fluids. The final expression of the constitutive equation for the stress tensor based on a particle scale approach presents some difference as compared with current constitutive models proposed in the current literature. Our constitutive equation considers the effect of a magnetic particle pressure, the average particle stresslet contribution in terms of an effective viscosity, the average particle rotlet in terms of a rotational viscosity, and a configurational tensor associated with dipole–dipole interactions. In addition, we discuss the situation in which the dipole moment of the particle is not frozen on it which leads to the necessity of an internal balance of angular momentum in a fluid element to close the governing equations of the model. An extension of the model for emulsions of polar deformable droplets is also proposed.
Absence of dimerization in Seff = 1/2 skew chain multiferroic Co2V2O7
Authors: Cao J. J. , Ouyang Z. W. , Li Z. R. , Wang L. , Chen Y. J. , Liu X. C. , Zhang W. J. , Xia Z. C.
Published: August 2024

Motivated by the multiferroic effects and quantum magnetization plateaus in the skew chain antiferromagnets T2V2O7 (T = Ni, Co), we have conducted a detailed density function theoretical study on Co2V2O7. The results show that the nearest-neighbor interchain interaction (J3/kB=−35.57 K) is not much greater than the intrachain interactions (J1/kB=−19.54 K and J2/kB=27.55 K), showing the absence of interchain dimerization of the Co ions. This indicates that the “dimer+monomer” model used for Ni2V2O7 [Cao et al., Phys. Rev. B 106, 184409 (2022)] is no longer applicable to Co2V2O7. Finally, the exact diagonalization of spin Hamiltonian, including anisotropic exchanges, produces the experimentally observed 1/2 and 3/4 magnetization plateaus.
Exact factorization of the photon–electron–nuclear wavefunction: Formulation and coupled-trajectory dynamics
Authors: Sangiogo Gil Eduarda , Lauvergnat David , Agostini Federica
Published: August 2024

We employ the exact-factorization formalism to study the coupled dynamics of photons, electrons, and nuclei at the quantum mechanical level, proposing illustrative examples of model situations of nonadiabatic dynamics and spontaneous emission of electron–nuclear systems in the regime of strong light–matter coupling. We make a particular choice of factorization for such a multi-component system, where the full wavefunction is factored as a conditional electronic amplitude and a marginal photon–nuclear amplitude. Then, we apply the coupled-trajectory mixed quantum–classical (CTMQC) algorithm to perform trajectory-based simulations, by treating photonic and nuclear degrees of freedom on equal footing in terms of classical-like trajectories. The analysis of the time-dependent potentials of the theory along with the assessment of the performance of CTMQC allows us to point out some limitations of the current approximations used in CTMQC. Meanwhile, comparing CTMQC with other trajectory-based algorithms, namely multi-trajectory Ehrenfest and Tully surface hopping, demonstrates the better quality of CTMQC predictions.
An unconditionally stable scheme for the immersed boundary method with application in cardiac mechanics
Authors: Ma Pengfei , Cai Li , Wang Xuan , Wang Yongheng , Luo Xiaoyu , Gao Hao
Published: August 2024

The stability of the immersed boundary (IB) method is a challenge in simulating fluid–structure interaction problems, where time step constraints are significantly stricter than in pure fluid simulations. We propose a novel unconditionally stable scheme for the immersed boundary finite element (IBFE) method. The structure is handled implicitly and characterized by strain energy functions, rather than being modeled as fibers or membranes. Through energy estimate, we prove the unconditional stability of the fully discrete approximation in the absence of the convective term. In real simulations of cardiac mechanics problems, the time step is much larger, only limited by the Courant–Friedrichs–Lewy condition of the fluid. The novelty of this work lies in the combination of dual interpolation and distribution operators, the Jacobian-free Newton–Krylov method for solving nonlinear algebraic systems, and the semi-Lagrangian method for handling the convective term. To validate the effectiveness and accuracy of our approach, we present various benchmarks and conduct a quasi-static simulation of a three-dimensional real left ventricular model. We have shown that the numerical stability of our scheme is very robust even with much larger time step compared to conventional explicit IB methods. Our work paves the way for further works on efficient solvers of the IBFE method.
Magnetic field induced spin wave reflection by a domain wall in synthetic antiferromagnets
Authors: Hadjoudja Amina , Garcia-Sanchez Felipe , Lopez-Diaz Luis
Published: August 2024

Micromagnetic simulations are used to investigate the effect of an external magnetic field on the interaction between domain walls and linearly polarized propagating spin waves in synthetic antiferromagnets. Two regimes with a sharp transition between them are found. At large fields, spin waves are strongly reflected by the domain wall and, consequently, the latter is propelled forward. At low fields, however, there is no reflection and yet the domain wall undergoes a small forward displacement, which is attributed to the change in linear momentum of the magnons as they pass through the domain wall and to the imbalance in the population of the two oscillation modes present in the linearly polarized excitation. The transition between the two regimes occurs at the field value for which the excitation frequency falls below the threshold of the high-frequency mode.
Interfacial engineering of orbital orientation for perpendicular magnetic anisotropy in Co-implanted CrI3 monolayer
Authors: Mo Yunying , Huang Xiaokun , Xu Jinlin , Jiang Xingan , Chen Chao , Jiang Xiangping , Liu Jun-Ming
Published: August 2024

Two-dimensional (2D) van der Waals (vdW) magnets are believed to be promising candidates for next-generation information storage, which requires both high Curie points (TC) and large perpendicular magnetic anisotropy (PMA). As one of the most well-known 2D magnets, CrI3 has large PMA but a relatively low TC. Recent theoretical works proposed that implanting metal atoms into the hollow sites of CrI3 could greatly boost TC. However, this process may have the unintended consequence of reducing the PMA and introducing in-plane magnetic anisotropy (IMA) instead. It is, therefore, highly required to implement an additional technique to enhance the PMA. In this work, we use the first-principles method to study the underlying mechanisms of the suppressed PMA (and induced IMA) in the Co-implanted CrI3 monolayer [denoted as Co-(CrI3)2] as an example. It is found that the Co-implantation-induced itinerant electrons cause the transition from PMA to IMA by tuning the orbital orientation of the states around the Fermi level, noting that an in-plane (or out-of-plane) electronic orbital leads to the out-of-plane (or in-plane) momentum that favors PMA (or IMA) due to the spin–orbit coupling. In order to restore the PMA, we predict that using the vdW substrate PtTe2 to construct a heterostructure with the Co-(CrI3)2 monolayer not only reduces the contributions of the interfacial out-of-plane orbitals but also generates additional intralayer in-plane orbitals, both supporting the PMA. Thus, this work provides alternative perspectives on enhancing PMA by interfacial engineering of orbital orientation, paving the way for the development of 2D strong magnets.
Sparsity and mixing effects in deep learning predictions of temperature and humidity
Authors: Drikakis Dimitris , Kokkinakis Ioannis W. , Tirchas Panagiotis
Published: August 2024

Developing deep learning models for predicting environmental data is a powerful tool that can significantly enhance equipment design, optimize the implementation of engineering systems, and deepen our understanding of the limitations imposed by flow physics. This study unequivocally demonstrates the accuracy of forecasting models based on popular deep learning algorithms, such as the long-short-term memory model, in turbulent mixing regions associated with flow physics arising from ventilation. This accuracy is contingent on two essential conditions. First, the sparsity of the sampling data is consistent with the model's accuracy overall. Second, the data sparsity ensures reasonable accuracy in the turbulent mixing regions. The investigation combines high-resolution flow simulation data with deep learning predictions of velocity, temperature, and relative humidity in a ventilated confined space. The results of this study, with their high accuracy, not only help to understand the mixing arising from flow circulation but also pave the way for developing predictive capabilities for environmental data.
RAD21
promotes oncogenesis and lethal progression of prostate cancer
Authors: Su Xiaofeng A. , Stopsack Konrad H. , Schmidt Daniel R. , Ma Duanduan , Li Zhe , Scheet Paul A. , Penney Kathryn L. , Lotan Tamara L. , Abida Wassim , DeArment Elise G. , Lu Kate , Janas Thomas , Hu Sofia , Vander Heiden Matthew G. , Loda Massimo , Boselli Monica , Amon Angelika , Mucci Lorelei A.
Published: August 2024

Higher levels of aneuploidy, characterized by imbalanced chromosome numbers, are associated with lethal progression in prostate cancer. However, how aneuploidy contributes to prostate cancer aggressiveness remains poorly understood. In this study, we assessed in patients which genes on chromosome 8q, one of the most frequently gained chromosome arms in prostate tumors, were most strongly associated with long-term risk of cancer progression to metastases and death from prostate cancer (lethal disease) in 403 patients and found the strongest candidate was cohesin subunit gene,
RAD21
, with an odds ratio of 3.7 (95% CI 1.8, 7.6) comparing the highest vs. lowest tertiles of mRNA expression and adjusting for overall aneuploidy burden and Gleason score, both strong prognostic factors in primary prostate cancer. Studying prostate cancer driven by the
TMPRSS2-ERG
oncogenic fusion, found in about half of all prostate tumors, we found that increased
RAD21
alleviated toxic oncogenic stress and DNA damage caused by oncogene expression. Data from both organoids and patients indicate that increased RAD21 thereby enables aggressive tumors to sustain tumor proliferation, and more broadly suggests one path through which tumors benefit from aneuploidy.
The deubiquitinase Usp7 in
Drosophila melanogaster
is required for synaptonemal complex maintenance
Authors: Lake Cathleen M. , Gardner Jennifer , Briggs Salam , Yu Zulin , McKown Grace , Hawley R. Scott
Published: August 2024

Meiosis is a form of cell division that is essential to sexually reproducing organisms and is therefore highly regulated. Each event of meiosis must occur at the correct developmental stage to ensure that chromosomes are segregated properly during both meiotic divisions. One unique meiosis-specific structure that is tightly regulated in terms of timing of assembly and disassembly is the synaptonemal complex (SC). While the mechanism(s) for assembly and disassembly of the SC are poorly understood in
Drosophila melanogaster
, posttranslational modifications, including ubiquitination and phosphorylation, are known to play a role. Here, we identify a role for the deubiquitinase Usp7 in the maintenance of the SC in early prophase and show that its function in SC maintenance is independent of the meiotic recombination process. Using two
usp7
shRNA constructs that result in different knockdown levels, we have shown that the presence of SC through early/mid-pachytene is critical for normal levels and placement of crossovers.
Selective optogenetic inhibition of Gα
q
or Gα
i
signaling by minimal RGS domains disrupts circuit functionality and circuit formation
Authors: Lockyer Jayde L. , Reading Andrew , Vicenzi Silvia , Zbela Agnieszka , Viswanathan Saranya , Delandre Caroline , Newland Jake W. , McMullen John P. D. , Marshall Owen J. , Gasperini Robert , Foa Lisa , Lin John Y.
Published: August 2024

Optogenetic techniques provide genetically targeted, spatially and temporally precise approaches to correlate cellular activities and physiological outcomes. In the nervous system, G protein-coupled receptors (GPCRs) have essential neuromodulatory functions through binding extracellular ligands to induce intracellular signaling cascades. In this work, we develop and validate an optogenetic tool that disrupts Gα
q
signaling through membrane recruitment of a minimal regulator of G protein signaling (RGS) domain. This approach, Photo-induced Gα Modulator—Inhibition of Gα
q
(PiGM-Iq), exhibited potent and selective inhibition of Gα
q
signaling. Using PiGM-Iq we alter the behavior of
Caenorhabditis elegans
and
Drosophila
with outcomes consistent with GPCR-Gα
q
disruption. PiGM-Iq changes axon guidance in cultured dorsal root ganglia neurons in response to serotonin. PiGM-Iq activation leads to developmental deficits in zebrafish embryos and larvae resulting in altered neuronal wiring and behavior. Furthermore, by altering the minimal RGS domain, we show that this approach is amenable to Gα
i
signaling. Our unique and robust optogenetic Gα inhibiting approaches complement existing neurobiological tools and can be used to investigate the functional effects neuromodulators that signal through GPCR and trimeric G proteins.
Contesting spaces
Authors: Junnier Frances , Shleykina Galina
Published: August 2024

In this study, we investigate the use of two pairs of Russian prepositions—v‍/‍na (‘in/on’) and iz/s (‘from’) with the noun Ukraine in X discourse. Since Ukrainian independence in 1991, v Ukraine and iz Ukraine have been used to indicate Ukrainian sovereignty and na and s used as their unmarked counterparts as defined by Russian linguistic tradition. Using a web-based set of tools called TWIG, we examine how posts containing the prepositional phrases construct stances toward the Russian invasion of Ukraine. Specifically, we examine the frequency of the prepositional phrases, their collocations, and the semantics conveyed by the collocational patterns. Our findings show notable differences in the collocational patterns of posts using v Ukraine versus na Ukraine. Analysis of these collocations suggests that posts using v Ukraine have a proximation effect to the conflict, while those using na Ukraine have a distancing effect.
Linguistic and cultural adaptation of the National Quality of Life Survey in Colombia for the deaf
population
Authors: Izquierdo Martínez Laura Catalina , Martínez-R Angela , Strasly Irene , Rivas Velarde Minerva
Published: August 2024

This article reports on the linguistic and cultural adaptation of Items of the National Quality of Life Survey
(NQLS 2018), which are included in a National Survey that explores the availability of reasonable accommodation for Deaf users in
a health care setting as well as health care access. We document the cultural and linguistic adaptation step-by-step, guided by a
literature review, participatory group discussions, and qualitative testing. This research addresses the dearth of accessible
research instruments for D‍/‍deaf persons in low and middle-income countries. This lack of accessible tools leads to double layers
of exclusion, and data gaps often lead to erroneous generalizations that do not accurately represent D‍/‍deaf populations.
Evidence gaps may result in poor service planning and inadequate policymaking. This study contributes to good practices in
language interpreting in research settings, disability research, and global health.
Immunologic signatures of response and resistance to nivolumab with ipilimumab in advanced metastatic cancer
Authors: Tsimberidou Apostolia M. , Alayli Farah A. , Okrah Kwame , Drakaki Alexandra , Khalil Danny N. , Kummar Shivaani , Khan Saad A. , Hodi F. Stephen , Oh David Y. , Cabanski Christopher R. , Gautam Shikha , Meier Stefanie L. , Amouzgar Meelad , Pfeiffer Shannon M. , Kageyama Robin , Yang EnJun , Spasic Marko , Tetzlaff Michael T. , Foo Wai Chin , Hollmann Travis J. , Li Yanyun , Adamow Matthew , Wong Phillip , Moore Jonni S. , Velichko Sharlene , Chen Richard O. , Kumar Dinesh , Bucktrout Samantha , Ibrahim Ramy , Dugan Ute , Salvador Lisa , Hubbard-Lucey Vanessa M. , O’Donnell-Tormey Jill , Santulli-Marotto Sandra , Butterfield Lisa H. , Da Silva Diane M. , Fairchild Justin , LaVallee Theresa M. , Padrón Lacey J. , Sharma Padmanee
Published: August 2024

Identifying pan-tumor biomarkers that predict responses to immune checkpoint inhibitors (ICI) is critically needed. In the AMADEUS clinical trial (NCT03651271), patients with various advanced solid tumors were assessed for changes in intratumoral CD8 percentages and their response to ICI. Patients were grouped based on tumoral CD8 levels: those with CD8 <15% (CD8-low) received nivolumab (anti-PD-1) plus ipilimumab (anti-CTLA4) and those with CD8 ≥15% (CD8-high) received nivolumab monotherapy. 79 patients (72 CD8-low and 7 CD8-high) were treated. The disease control rate was 25.0% (18/72; 95% CI: 15.8–35.2) in CD8-low and 14.3% (1/7; 95% CI: 1.1–43.8) in CD8-high. Tumors from 35.9% (14/39; 95% CI: 21.8–51.4) of patients converted from CD8 <15% pretreatment to ≥15% after treatment. Multiomic analyses showed that CD8-low responders had an inflammatory tumor microenvironment pretreatment, enhanced by an influx of CD8 T cells, CD4 T cells, B cells, and macrophages upon treatment. These findings reveal crucial pan-cancer immunological features for ICI response in patients with metastatic disease.
Quantum geometric perspective on the origin of quantum-conditioned curvatures
Authors: Nasser Tawfik Abdel , Pasqua Antonio , Waqas Muhammad , Alshehri Azzah A , Kr Haldar Prabir
Published: August 2024

The quantization of the gravitational field, which includes the metric field, has been investigated using various methods such as loop quantum gravity, quantum field theory, and string theory. Nevertheless, an alternative strategy to tackle the challenge of merging the fundamentally different theories of general relativity (GR) and quantum mechanics (QM) is through a quantum geometric approach. This particular approach entails extending QM to relativistic energies and finite gravitational fields, while also expanding the continuous Riemann to a discretized (quantized) Finsler–Hamilton geometry. By embracing this method, it may be feasible to bridge the gap between GR and QM or even achieve their unification. The resulting fundamental tensor appears to blend its original classical and quantum characteristics, effectively integrating quantum-mechanically induced revisions to the affine connections and spacetime curvatures. Our study primarily focuses on investigating the Ricci curvature tensor in the context of the Einstein–Gilbert–Straus metric. By employing both analytical and numerical methods, we have identified quantum-conditioned curvatures (QCC) that act as additional sources of gravitation. These QCC exhibit a fundamental difference from the traditional curvatures described by Einsteinian GR. While the Ricci curvatures are predominantly positive across most regions, the quantized Ricci curvatures display negativity. We conclude that the QCC (a) possess an intrinsic, essential, and real character, (b) should not be disregarded due to their significant magnitude, and (c) are fundamentally different from the curvatures found in classical GR. Moreover, we conclude that the proposed quantum geometric approach may offer an alternative mathematical framework for understanding the emergence of quantum gravity.
Observation of Young’s double-slit phenomenon in anti-PT-symmetric electrical circuits
Authors: Pan Keyu , Wang Xiumei , Shen Xizhou , Zhou Haoyi , Zhou Xingping
Published: August 2024

In the last few decades, interference has been extensively studied in both the quantum and classical fields, which reveals light volatility and is widely used for high-precision measurements. We have put forward the phenomenon in which the discrete diffraction and interference phenomena, presented by the time-varying voltage of a Su–Schrieffer–Heeger circuit model with an anti-PT (APT) symmetry. To demonstrate Young’s double-slit phenomenon in an APT circuit, we initially explore the coupled mode theory of voltage in the broken phase, observe discrete diffraction under single excitation and interference under double excitations. Furthermore, we design a phase-shifting circuit to observe the effects of phase difference and distance on discrete interference. Our work combines the effects in optics with condensed matter physics, show the Young’s double-slit phenomenon in electrical circuits theoretically and experimentally.
Exotic phases induced by RKKY interaction in the square lattice
Authors: Wac A Vela , Albarracín F A Gómez , Cabra D C
Published: August 2024

We study a model of Ising spins in which direct exchange interactions compete with the Ruderman–Kittel–Kasuya–Yosida (RKKY) coupling, which may arise effectively from itinerant electrons. We consider the model in the two-dimensional square lattice and focus on values of the RKKY coupling constant (

J

RKKY

) and the Fermi momentum (

k
F

) that induce strong frustration. We study the low-temperature magnetic field phase diagram using Monte Carlo simulations, considering several nearest neighbors in the RKKY interaction. Magnetic frustration yields a rich phase diagram with a variety of exotic phases. We compute the structure factors and define appropriate order parameters to describe the transitions. We also discuss the validity of the approximation made for long-range couplings and analytically demonstrate the change in the coexistence lines in the phase diagram by including up to the tenth nearest neighbors.
Low-temperature magnetic properties of the S = 1/2 kagomé antiferromagnet YCo3(OH)6.55Br2.45
Authors: Yu Zhenwei , Liang Hui , Wang Yiyan , Li Na , Sun Yan , Wu Dandan , Zhou Ying , Ding Zongling , Sun Jin , He Tianbo , Wu Ziyang , Wang Junfeng , Sun Xuefeng , Li Qiuju
Published: August 2024

We report the synthesis, crystal structure, magnetization and specific heat studies of YCo3(OH)6.55Br2.45 single crystal. YCo3(OH)6.55Br2.45 crystallizes in trigonal structure, in which Co2+ ions form a perfect kagomé lattice. The magnetic susceptibility reveals successive magnetic transitions at 6.5 and 7.8 K and the Curie–Weiss fitting demonstrates that YCo3(OH)6.55Br2.45 has strong antiferromagnetic coupling and pronounced magnetic frustration effect. Specific heat data suggest that low-T magnetic transitions are attributed to antiferromagnetic ordering of Co2+ ions and the magnetic entropy points to effective 1/2 spin in the system. These results indicate that an unusual magnetic ordering state with effective spin-1/2 is realized in kagomé lattice system YCo3(OH)6.55Br2.45.
Depinning of charge density waves of different dimensionalities in 1T-TiSe2 and NbSe3
Authors: Wei Xiaoxiao , Zhu Liang , Wu Ziming , Shi Zhenzhong
Published: August 2024

Nonlinear transport behavior is one of the signatures of the formation of electronic crystals such as charge density wave (CDW), as it provides evidence for their collective motion. Such experimental evidence has been widely reported in quasi-one-dimensional (1D) materials but is rarely studied in 2D systems. Only a few studies on the RTe3 materials have been previsouly reported. Here we report for the first time the observation of CDW depinning and sliding in the layered 1T-TiSe2 compound, based on the observation of (1) nonlinear voltage-current characteristics and (2) the electrical noise, which are associated with the CDW depinning and sliding process. Similar measurements are also conducted on quasi-1D system NbSe3. The depinning behavior of the CDWs with different dimensionalities in these two systems are compared. It is found that the threshold electric field (E

T
) increases linearly with decreasing temperature for the 2D case, consistent with previous results on RTe3, while it demonstrated an activated behavior in 1D, as expected within the weak-pinning Fukuyama–Lee–Rice framework. Such a distinction of the threshold behavior in CDW systems of different dimensions therefore indicates a possible strong pinning picture in higher-dimensional CDW systems in general. E

T
is found to be much higher in 1T-TiSe2, consistent with a strong pinning picture, and could account for the scarcity of the depinning study in these 2D systems. Our results thus pave the way for a unified understanding of the CDW collective motion in different dimensionalities.
Effects of electronic correlation on topological properties of Kagome semimetal Ni3In2S2
Authors: Das P , Saha P , Singh M , Kumar P , Patnaik S
Published: August 2024

Kagome metals gain attention as they manifest a spectrum of quantum phenomena such as superconductivity, charge order, frustrated magnetism, and allied correlated states of condensed matter. With regard to electronic band structure, several of them exhibit non-trivial topological characteristics. Here, we present a thorough investigation on the growth and the physical properties of single crystals of Ni3In2S2 which is established to be a Dirac nodal line Kagome semimetal. Extensive characterization is attained through temperature and field-dependent resistivity, angle-dependent magnetoresistance (MR) and specific heat measurements. The central question we seek to address is the effect of electronic correlations in suppressing the manifestation of topological characteristics. In most metals, the Fermi liquid behaviour is restricted to a narrow range of temperatures. Here, we show that Ni3In2S2 follows the Fermi-liquid behaviour up to 86 K. This phenomenon is further supported by a high Kadowaki–Woods ratio obtained through specific heat analysis. Different interpretations of the magneto-transport study reveal that MR exhibits linear behaviour, suggesting the presence of Dirac fermions at lower temperatures. The angle-dependent magneto-transport study obeys the Voigt–Thomson formula. This, on the contrary, implies the classical origin of MR. Thus, the effect of strong electron correlation in Ni3In2S2 manifests itself in the anisotropic magneto-transport. Furthermore, the magnetization measurement shows the presence of de-Haas van Alphen oscillations. Calculations of the Berry phase provide insights into the topological features in the Kagome semimetal Ni3In2S2.
Anti-matching effect in a two dimensional driven vortex lattice in the presence of periodic pinning
Authors: P Akhilesh M , Joseph Toby
Published: August 2024

The dynamics of a driven superconducting vortex lattice in a two-dimensional (2D) periodic potential of square symmetry is studied using Brownian dynamics simulations. The range and strength of the vortex-substrate interaction are taken to be of the same order as that of the vortex-vortex interaction. The matching effect in a driven vortex lattice in the presence of a periodic array of pinning centers refers to the enhanced resistance to the vortex lattice motion when the ratio of the number of vortices to the number of pinning centers (called the filling fraction) takes simple fractional values. In particular, one expects a pronounced matching effect when the filling fraction is one. Contrary to this expectation, a drop in the vortex lattice mobility is observed as the filling fraction is increased from value one. This anti-matching effect can be understood in terms of the structural change in the vortex lattice as the filling fraction is varied. The dip observed in vortex mobility as a function of temperature when the filling fraction equals one (Joseph T 2020 Physica A 556 124737), is studied for other values of filling above and below one. The behavior is found to persist for other fillings as well and is associated with the melting of the vortex lattice. The temperature at which the lattice melts is found to increase with drive and explains the shift in the temperature at which mobility is a minimum, locally.