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Abstract Our study develops a generative adversarial network (GAN)-based method that generates faithful synthetic image data of human cardiomyocytes at varying stages in their maturation process, as a tool to significantly enhance the classification accuracy of cells and ultimately assist the throughput of computational analysis of cellular structure and functions. Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) were cultured on micropatterned collagen coated hydrogels of physiological stiffnesses to facilitate maturation and optical measurements were performed for their structural and functional analyses. Control groups were cultured on collagen coated glass well plates. These image recordings were used as the real data to train the GAN model. The results show the GAN approach is able to replicate true features from the real data, and inclusion of such synthetic data significantly improves the classification accuracy compared to usage of only real experimental data that is often limited in scale and diversity. The proposed model outperformed four conventional machine learning algorithms with respect to improved data generalization ability and data classification by incorporating synthetic data. This work demonstrates the importance of integrating synthetic data in situations where there are limited sample sizes and thus, effectively addresses the challenges imposed by data availability.

Abstract The Fe80P x C20-x ingots and amorphous ribbons (4.5 ≤ x ≤ 6.5) are arc melted and melt spun respectively. The Rhodamine B degradation performance of as spun and annealed ribbons are investigated with various methods. In present alloys, increasing P content (c P) can inhibit the precipitation of primary α-Fe and graphite phases, and promote the formation of eutectic α-Fe + Fe3C + Fe3P phases in ingots and annealed ribbons. With increasing annealing temperature (T an), the primary α-Fe grain size of the ribbons with c P = 4.5 at.% increases gradually and that of the ribbons with c P = 6.5 at.% increases firstly and then decreases. The degradation performance and reusability of the ribbons show a similar T an-dependent behavior, which can be explained by the size effect of the galvanic cells. Meanwhile, the saturation magnetisation B s and coercivity H c of the ribbons with c P = 4.5 and 6.5 at.% increase with increasing T an, showing a near-linear change of the reaction rate constant k against ln (B s·H c). This work not only studies the mechanism of improving degradation performance for FePC amorphous alloys by annealing treatment, but also reveals a correlation between degradation performance and magnetization performance of FePC alloys.

Abstract This study presents a dual-functional thin film, known as Ag nanoparticles decorated, ZnO nanorods coated silica nanofibers (AgNP-ZnONR-SNF), which demonstrates remarkable capabilities in both water purification and organic pollutants sensing. The 3D fibrous structure of ZnONR-SNF provides a large surface-area-to-volume ratio for piezo- and photo-catalytic degradation of organic pollutants under UV irradiation, achieving over 98% efficiency. Ag nanoparticles decorated on ZnONR-SNF form “hot-spot” that significantly enhance the surface-enhanced Raman spectroscopy (SERS) signal, resulting in an enhancement factor of 1056 and an experimental detection limit of 1 pg mL−1. Furthermore, a machine learning algorithm is developed for the qualitative and quantitative detection of multiple contaminants, achieving high accuracy (92.3%) and specificity (89.3%) without the need for preliminary processing of Raman spectra. This work provides a promising nanoengineering solution for water purification and sensing with improved detection accuracy, purification efficiency, and cost-effectiveness.

Abstract This paper demonstrates the design, synthesis, simulation, and testing of three distinct geometries of plasmonic gold nanoparticles for on-chip DNA screening towards liquid biopsy. By employing a seed-mediated growth method, we have synthesized gold nanospheres, nanorods, and nanobipyramids. In parallel, we developed numerical simulations to understand the effects of nanoparticle geometry on the resonance features and refractive index sensitivity. Both experimental and simulation results were compared through a series of studies including in-solution and on-chip tests. We have thoroughly characterized the impact of nanoparticle geometry on the sensitivity to circulating tumor DNA, with immediate implications for liquid biopsy. The results agree well with theoretical predictions and simulations, including both bulk refractive index sensitivity and thin film sensitivity. Importantly, this work quantitatively establishes the link between nanoparticle geometry and efficacy in detecting rare circulating biomarkers. The nanobipyramids provided the highest sensitivity, approximately doubling the sensitivity compared to nanorods. To the best of our knowledge this is the first report carrying through geometric effects of simulation to clinically relevant biosensing. We put forth here synthesis and testing of three nanoparticle geometries, and a framework for both experimental and theoretical validation of plasmonic sensitivities towards liquid biopsy.

Animals constantly balance seeking food with avoiding predators. Here, the authors report that CRF positive neurons in the paraventricular thalamus projecting to the nucleus accumbens in rats are an indispensable component of a feedback circuit that can interrupt appetitive behaviour in favor of a defensive response in the presence of a competing threat stimulus.

Von Willebrand factor (VWF) is a large glycoprotein in the blood secreted from endothelial cells lining the blood vessel and activation of VWF leads to formation of VWF-platelet complexes or thrombi. Here authors use single-molecule force measurement, X-ray crystallography and functional measurements to monitor the activation of VWF via mechanical unfolding of the autoinhibitory module (AIM).

Magnetotail reconnection plays a crucial role in explosive energy conversion in geospace. Here, the authors show that magnetotail reconnection starts from electron reconnection in the presence of a strong external driver, which then develops into ion reconnection.

The effect of the lattice degrees of freedom on the metal-insulator transition of VO2 remains a topic of debate. Here the authors show that the lattice compatibility of the high temperature tetragonal phase and the low-temperature monoclinic phase strongly influences the electronic transition, as manifested in the tunability of its hysteresis via chemical substitution.

Magnetoelectric effect enables versatile electronic and spintronic devices. Here the authors demonstrate a different strategy to achieve magnetoelectric coupling in which the electric polarization is controlled by magnetic spin state transition instead of the traditional ferro- or antiferromagnetic order.

Organic materials hold great potential of for spintronic applications. Here the authors show electronic phase dependent magnetoresistance (MR) effect in LPCMO/Alq3/Co junctions with large MR up to 440% at 10 K as well as electrical Hanle effect as the Hallmark of the spin injection.

Perovskite manganites exhibit intriguing but poorly understood properties, including multiferroicity. Here, the authors synthesize a Ce3Mn8 cluster that structurally resembles a perovskite repeat unit, and use this molecular analogue to elucidate mechanisms driving bulk perovskite properties.

Abstract Topological materials with exotic quantum properties are promising candidates for quantum spin electronics. Different classes of topological materials, including Weyl semimetal, topological superconductor, topological insulator and Axion insulator, etc., can be connected to each other via quantum phase transition. For example, it is believed that a trivial band insulator can be twisted into topological phase by increasing spin-orbital coupling or changing the parameters of crystal lattice. With the results of LDA calculation and measurement by angle-resolved photoemission spectroscopy (ARPES), we demonstrate in this work that the electronic structure of SrSn2As2 single crystal has the texture of band inversion near the critical point. The results indicate the possibility of realizing topological quantum phase transition in SrSn2As2 single crystal and obtaining different exotic quantum states.

Abstract Atmospheric aerosol particles acting as cloud condensation nuclei (CCN) are key elements in the hydrological cycle and climate. To improve our understanding of the activation characteristics of CCN and to obtain accurate predictions of their concentrations, a long-term field campaign was carried out in the Yangtze River Delta, China. The results indicated that the CCN were easier to activate in this relatively polluted rural station than in clean (e.g., the Amazon region) or dusty (e.g., Kanpur-spring) locations, but were harder to activate than in more polluted urban areas (e.g., Beijing). An improved method, using two additional parameters—the maximum activation fraction and the degree of heterogeneity, is proposed to predict the accurate, size-resolved concentration of CCN. The value ranges and prediction uncertainties of these parameters were evaluated. The CCN predicted using this improved method with size-resolved chemical compositions under an assumption that all particles were internally mixed showed the best agreement with the long-term field measurements.

The platelets detect and respond to shear stress generated by blood flow. Here the authors show that the binding of the soluble von Willebrand factor to its receptor GPIba under physiological shear stress induces receptor's domain unfolding on the platelet and signalling into the platelet, leading to platelets clearance.

Phase transitions in topologically non-trivial systems are characterized by changes of topological invariants, rather than conventional order parameters. Here, the authors propose a real-space topological phase transition upon pair annihilation of emergent monopoles inherent in chiral magnet MnGe.