Browse Articles

Angle-controlled strong and weak coupling in photon molecules

Quantum secure direct communication based on quantum error correction code

Quantum secure direct communication (QSDC) enables the message sender to directly transmit messages to the message receiver through quantum channel without keys. Environmental noise is the main obstacle for QSDC's practicality. For enhancing QSDC's noise robustness, we introduce the quantum error correction (QEC) code into QSDC and propose the QSDC protocol based on the redundancy code. This QSDC protocol correlates atomic state with the electron–photon entangled pairs and transmits photons in quantum channels for two rounds. The parties can construct the remote atomic logical entanglement channel and decode messages with the heralded photonic Bell state measurement (BSM) and single electron measurement. This QSDC protocol is unconditionally secure in theory and has some advantages. First, benefiting from the heralded photonic BSM, it can eliminate the influence from photon transmission loss and has the potential to realize long-distance secure message transmission. Second, taking use of the error correction function of the repetition code, the error rate caused by the decoherence during the second round of photon transmission can be reduced, which can reduce the message error and increase the secret message capacity. Third, the whole protocol is feasible under current experimental condition. Our QSDC protocol can be extended to use other stronger QEC code. It provides a promising method to promote QSDC's practicality in the future.

MLP Enhanced CO2 Emission Prediction Model with LWSSA Nature Inspired Optimization

Abstract Environmental degradation due to the rapid increase in CO₂ emissions is a pressing global challenge, necessitating innovative solutions for accurate prediction and policy development. Machine learning (ML) techniques offer a robust approach to modeling complex relationships between various factors influencing emissions. Furthermore, ML models can learn and interpret the significance of each factor’s contribution to the rise of CO2. This study proposes a novel hybrid framework combining a Multi-Layer Perceptron (MLP) with an enhanced Locally Weighted Salp Swarm Algorithm (LWSSA) to address the limitations of traditional optimization techniques, such as premature convergence and stagnation in locally optimal solutions. The LWSSA improves the standard Salp Swarm Algorithm (SSA) by incorporating a Locally Weighted Mechanism (LWM) and a Mutation Mechanism (MM) for greater exploration and exploitation. The LWSSA-MLP framework achieved a prediction accuracy of 97% and outperformed traditional optimizer-based MLP models across several evaluation metrics. A permutation feature significance analysis identified global trade, coal energy, export levels, urbanization, and natural resources as the most influential factors in CO₂ emissions, offering valuable insights for targeted interventions. The study provides a reliable and scalable framework for CO₂ emission prediction, contributing to actionable strategies for sustainable development and environmental resilience.

The band structure and carrier recombination mechanism of α/β-phase tellurium homojunction investigated by infrared photoluminescence

During the synthesis of tellurium (Te) crystals, the coexistence of multiple crystalline phases (α-Te, β-Te, and γ-Te) with diverse structures commonly occurs, leading to instability and complexity in the performance of Te-based optoelectronic devices. This study employs physical vapor deposition to synthesize Te crystals of various sizes and morphologies, followed by spatially and temperature-dependent evaluation using Raman mapping and infrared photoluminescence (PL) spectroscopy. Spatially resolved results reveal that the size and morphology of Te crystals significantly influence the energy and peak profiles of Raman and PL spectra. Statistical analysis of spatially random sampling indicates the PL peak energies of Te crystals follow a lognormal distribution in terms of their occurrence frequencies, reflecting the complex interplay of multiple factors during crystal growth. This results in the coexistence of α-Te and β-Te phases, forming α/β-Te heterophase homojunction (HPHJ). Meanwhile, temperature-dependent PL results, obtained for the range of 3–290 K, reveal multi-peak competitive behavior in the PL spectra, accompanied by S-shaped shifts in peak energy. These features can be rationally explained by an interface transition-recombination mechanism based on the I-type α/β-Te HPHJ model. It also confirms infrared PL spectroscopy is an effective method for identifying the crystalline phase composition of Te crystals.

Antisense mediated blockade of Dickkopf 1 attenuates tumor survival, metastases and bone damage in experimental osteosarcoma

Realization of p-type MA-based perovskite solar cells based on exposure of the (002) facet

The crystallographic orientation of perovskite crystals significantly influences their photoelectric performance and associated photovoltaic devices. The classic perovskite (MAPbI3) films based on solution processing usually suffer from chaotic orientations. The impact of preferential crystallographic orientation of MAPbI3 thin films on the carrier transport is still far from being well understood. In comparison with the (011) and (111) facets, our density functional theory results revealed that the hole carrier in the (001) facet exhibits superior carrier transport properties. Herein, the highly oriented (001) FAPbI3 could serve as growth templates and promote the (002) orientations of MAPbI3 perovskite. Furthermore, the p-type doping in MAPbI3 was obtained by controlling the amount of MAI. The (002)-dominated MAPbI3 perovskite with p-type characteristics exhibits exceptional carrier transport properties, thereby enhancing device performance.

Assessment of upper respiratory and gut bacterial microbiomes during COVID-19 infection in adults: potential aerodigestive transmission

Defect-mediated electron–phonon coupling in halide double perovskite

Optically active defects often play a crucial role in governing the light emission as well as the electronic properties of materials. Moreover, defect-mediated states in the midgap region can trap electrons, thus opening a path for the recombination of electrons and holes in lower energy states that may require phonons in the process. Considering this, we have probed electron–phonon interaction in halide perovskite systems with the introduction of defects and investigated the thermal effect on this interaction. Here, we report Raman spectroscopic study of the thermal evolution of electron–phonon coupling, which is tunable with the crystal growth conditions, in the halide perovskite systems Cs2AgInCl6 and Cs2NaInCl6. The signature of electron–phonon coupling is observed as a Fano anomaly in the lowest frequency phonon mode (51 cm−1), which evolves with temperature. In addition, we observe a broad band in the photoluminescence (PL) measurements for the defect-mediated systems, which is otherwise absent in defect-free halide perovskite. The simultaneous observation of the Fano anomaly in the Raman spectrum and the emergence of the PL band suggests the defect-mediated midgap states and the consequent existence of electron–phonon coupling in the double perovskite.

Probabilistic nested model selection in pharmacokinetic analysis of DCE-MRI data in animal model of cerebral tumor

Abstract Best current practice in the analysis of dynamic contrast enhanced (DCE)-MRI is to employ a voxel-by-voxel model selection from a hierarchy of nested models. This nested model selection (NMS) assumes that the observed time-trace of contrast-agent (CA) concentration within a voxel, corresponds to a singular physiologically nested model. However, admixtures of different models may exist within a voxel’s CA time-trace. This study introduces an unsupervised feature engineering technique (Kohonen-Self-Organizing-Map (K-SOM)) to estimate the voxel-wise probability of each nested model. Sixty-six immune-compromised-RNU rats were implanted with human U-251 N cancer cells, and DCE-MRI data were acquired from all the rat brains. The time-trace of change in the longitudinal-relaxivity (ΔR 1 ) for all animals’ brain voxels was calculated. DCE-MRI pharmacokinetic (PK) analysis was performed using NMS to estimate three model regions: Model-1: normal vasculature without leakage, Model-2: tumor tissues with leakage without back-flux to the vasculature, Model-3: tumor vessels with leakage and back-flux. Approximately two hundred thirty thousand (229,314) normalized ΔR 1 profiles of animals’ brain voxels along with their NMS results were used to build a K-SOM (topology-size: 8 × 8, with competitive-learning algorithm) and probability map of each model. K -fold nested-cross-validation (NCV, k = 10) was used to evaluate the performance of the K-SOM probabilistic-NMS (PNMS) technique against the NMS technique. The K-SOM PNMS’s estimation for the leaky tumor regions were strongly similar (Dice-Similarity-Coefficient, DSC = 0.774 [CI: 0.731–0.823], and 0.866 [CI: 0.828–0.912] for Models 2 and 3, respectively) to their respective NMS regions. The mean-percent-differences (MPDs, NCV, k = 10) for the estimated permeability parameters by the two techniques were: -28%, + 18%, and + 24%, for v p , K trans , and v e , respectively. The KSOM-PNMS technique produced microvasculature parameters and NMS regions less impacted by the arterial-input-function dispersion effect. This study introduces an unsupervised model-averaging technique (K-SOM) to estimate the contribution of different nested-models in PK analysis and provides a faster estimate of permeability parameters.

Dynamic manipulation of ultrasonic beams by coding Moiré metasurfaces

Dynamic acoustic beam manipulation via tunable acoustic metasurfaces (AMs) has attracted significant attention. However, most current tunable AMs are primarily designed for airborne sound, feature complex structural components, and serve a singular purpose. This study proposes a coding Moiré metasurface (CMM) consisting of two cascaded acoustic coding metasurfaces (ACMs) to dynamically manipulate ultrasonic beams in water. The CMM merges the characteristics of Moiré AMs and coding and can achieve different ultrasonic beam manipulations by rotating the ACM and changing the coding sequence. This is demonstrated by presenting CMMs with stripe and checkerboard coding patterns: the former split an ultrasonic beam into two dynamically omnidirectional scanning beams, while the latter divided it into four sections. Finally, two coding bits are employed to construct the CMM samples: a water unit for bit “0” and a photosensitive resin unit for bit “1.” Experimental results demonstrate that the CMM can dynamically manipulate ultrasonic beams. The proposed CMMs hold substantial potential for acoustic communication and dynamic detection applications.

Mind the leaf anatomy while taking ground truth with portable chlorophyll meters

Abstract A wide range of portable chlorophyll meters are increasingly being used to measure leaf chlorophyll content as an indicator of plant performance, providing reference data for remote sensing studies. We tested the effect of leaf anatomy on the relationship between optical assessments of chlorophyll (Chl) against biochemically determined Chl content as a reference. Optical Chl assessments included measurements taken by four chlorophyll meters: three transmittance-based (SPAD-502, Dualex-4 Scientific, and MultispeQ 2.0), one fluorescence-based (CCM-300), and vegetation indices calculated from the 400–2500 nm leaf reflectance acquired using an ASD FieldSpec and a contact plant probe. Three leaf types with different anatomy were included: dorsiventral laminar leaves, grass leaves, and needles. On laminar leaves, all instruments performed well for chlorophyll content estimation (R2 > 0.80, nRMSE < 15%), regardless of the variation in their specific internal structure (mesomorphic, scleromorphic, or scleromorphic with hypodermis), similarly to the performance of four reflectance indices (R2 > 0.90, nRMSE < 16%). For grasses, the model to predict chlorophyll content across multiple species had low performance with CCM-300 (R2 = 0.45, nRMSE = 11%) and failed for SPAD. For Norway spruce needles, the relation of CCM-300 values to chlorophyll content was also weak (R2 = 0.45, nRMSE = 11%). To improve the accuracy of data used for remote sensing algorithm development, we recommend calibration of chlorophyll meter measurements with biochemical assessments, especially for species with anatomy other than laminar dicot leaves. The take-home message is that portable chlorophyll meters perform well for laminar leaves and grasses with wider leaves, however, their accuracy is limited for conifer needles and narrow grass leaves. Species-specific calibrations are necessary to account for anatomical variations, and adjustments in sampling protocols may be required to improve measurement reliability.

Observation of a two-dimensional topological metal in acoustic metamaterials

A two-dimensional topological metal with anti-helical-like edge states has been predicted recently but has not been confirmed experimentally. In this paper, we report an experimental realization of this topological metal in acoustic metamaterial by introducing a time-reversal symmetry protected square lattice. The edge states appearing in gapless bulk bands are observed by measuring the projected dispersions and acoustic pressure field distributions. Moreover, these edge states propagate in the same direction when simultaneously exciting two sources with a fixed phase difference. Interestingly, by simply changing the coupling tubes, we realized the transformation of an acoustic topological metal to a topological insulator. Our work not only pushes forward the studies of topological metals but also inspires the design of multifunctional acoustic devices.

Titanium dioxide -mediated regulation of enzymatic and non-enzymatic antioxidants, pigments, and diosgenin content promotes cold stress tolerance in Trigonella foenum-graecum L.

Strain manipulation of spin-polarized topological phase in WSe2/CrI3 heterostructure

Here, based on first-principles calculations and topological analysis, we show that the spin-polarized topological phase is present in a van der Waals (vdW) heterostructure WSe2/CrI3. We reveal that magnetism induced by proximity effects in the heterostructure breaks the time-reversal symmetry (TRS) and thus induces gapped topological edge states, exhibiting the TRS-breaking quantum spin Hall (QSH) effect. By applying a stress field, the WSe2/CrI3 heterostructure manifests enhanced spin polarization, Rashba splitting, and tunable bandgap. The TRS-breaking QSH effect observed in the WSe2/CrI3 heterostructure exhibits remarkable robustness against interlayer shearing. The distinct anisotropy associated with in-plane strain provides precise manipulation strategies for bandgap engineering. Notably, in-plane tensile strain can significantly increase the nontrivial bandgap by up to 98 meV, suggesting the magnetic WSe2/CrI3 heterostructure represents an outstanding platform for achieving the TRS-breaking QSH effect at room temperature. Our findings provide a theoretical foundation for the development of low-dissipation spintronic nanodevices.

Sinomenine attenuates uremia vascular calcification by miR-143-5p

Abstract Vascular calcification is considered to be a killer of the cardiovascular system, involved inflammation and immunity. There is no approved therapeutic strategy for the prevention of vascular calcification. Sinomenine exhibited anti-inflammatory and immunosuppressive effects. Objective of this study was to investigate the effect of sinomenine in vascular calcification and its potential molecular mechanism. Adenine-induced uremic rats were constructed and administrated with sinomenine. Optical clearing of aortas, alizarin red staining, von Kossa staining, calcification quantification, micro-CT analyses of vascular calcification were performed to analyze calcification in aortas. Administration of 40 mg/kg/d sinomenine effectively alleviated vascular calcification in uremic rats. The miRNA sequencing revealed differentially expressed miRNAs in aortas and bioinformatic analysis assisted with miRNA screening. We screened 9 differential expressed miRNAs and their predicted target genes. By qRT-PCR, we validated that the expression of rno-miR-143-5p was corresponding to our prediction. Sinomenine inhibited vascular smooth muscle cells (VSMCs) calcification, accompanied with miR-143-5p upregulation. MiR-143-5p mimic decreased VSMCs calcification in high phosphate condition. On the contrary, miR-143-5p inhibitor increased VSMCs calcification in high phosphate condition, which was inhibited by sinomenine. In chronic kidney disease patients with vascular calcification, the expression level of circulating miR-143-5p was lower than those without vascular calcification. Sinomenine significantly inhibited vascular calcification in VSMCs and uremic rat. MiR-143-5p was one of the collection of miRNAs modified by sinomenine in vascular calcification. Reduction of miR-143-5p in VSMCs was not only a concomitant phenomenon in pro-calcification condition but also contribute to VSMCs calcification. Circulating miR-143-5p was supposed to be a potential biomarker for vascular calcification in chronic kidney disease patients. In conclusion, sinomenine effectively alleviated vascular calcification, which was attributed to miR-143-5p regulation partly.

An innovative 3D-NAND design based on light-emitting cell for high reliability and low power consumption

The advancements in 3D-NAND technology have significantly increased the number of vertically stacked cells, which are controlled via word lines (WLs), enabling higher cell density and reducing costs. However, the increase in vertical cell layers has also introduced challenges such as higher power consumption and diminished current levels, both of which compromise the reliability of memory cells. At the same time, the demand for high cell reliability and low power consumption has been growing, driven by the expanding needs of storage applications in big data and cloud services. In this study, we propose an optically readable light-emitting memory (LEM) as a unit cell within 3D-NAND architecture. This innovative design exhibits both effective memory performance and light-emitting capabilities. Unlike conventional memory cells that require all WLs to be biased during read operation, the LEM requires only a read bias on the selected WL to detect the light intensity, which directly correlates with the stored data state. By applying voltage only to the selected WL, power consumption is reduced by approximately 45%. In addition, issues such as read disturbances and low cell currents that affect cell reliability are effectively mitigated, resulting in an expected improvement in the read window.

Photocatalytic removal of textile wastewater-originated methylene blue and malachite green dyes using spent black tea extract-coated silver nanoparticles

Uniaxial magnetic anisotropy and weak phonon–spin coupling of a single Ni atom bonded to iridium-doped graphene

We investigate the magnetism and vibrational mode of a single Ni atom bonded to iridium-doped graphene. It is found that the Ni atom exhibits a large magnetic anisotropy energy of 53 meV, and the magnetic anisotropy is perfectly uniaxial. There are no vibrational modes below 40 meV for the Ni atom, which disables the efficient coupling between the spin and phonon at the low magnetic field. The uniaxial magnetic anisotropy combining with the weak phonon–spin coupling effectively resists the quantum tunneling and spin flip, making the Ni atom a viable single atom magnet for information storage.

Relationship between oral hypofunction and medical expenditure in older adults in Japan

Write error reduction in magnetic tunnel junctions for voltage-controlled magnetoresistive random access memory by using exchange coupled free layer

Voltage-controlled magnetoresistive random access memory (VC-MRAM) is an emerging nonvolatile memory based on the voltage-controlled magnetic anisotropy (VCMA) effect. It has been garnering considerable attention because of its fast and low-power operation. However, two major issues must be addressed for practical applications. First, the voltage-induced switching of the free layer magnetization is sensitive to ultrashort voltage pulse duration. Second, the write error rate (WER) of the voltage-induced switching is high. To address these issues, a magnetic tunnel junction (MTJ) structure with an exchange coupled free layer, consisting of a precession layer with the VCMA effect and an anchor layer without the VCMA effect, is proposed. The anchor layer prevents the precession layer from returning to its initial direction, thereby reducing the WER without requiring the voltage pulse duration to be precisely controlled. The write operation of the proposed MTJ with an exchange coupled free layer was analyzed using the macrospin model. Using optimized MTJ parameters, a low WER of approximately 10−6 was obtained for an 80 nm MTJ without requiring the pulse duration to be precisely controlled. These results facilitate the reduction of the WER for VC-MRAM and improve its usability, thereby expanding its range of applications.