Site-specific variations are challenges for pooling analyses in multi-center studies. This work aims to propose an inter-site harmonization method based on dual generative adversarial networks (GANs) ...for diffusion tensor imaging (DTI) derived metrics on neonatal brains.
DTI-derived metrics (fractional anisotropy, FA; mean diffusivity, MD) are obtained on age-matched neonates without magnetic resonance imaging (MRI) abnormalities: 42 neonates from site 1 and 42 neonates from site 2. Significant inter-site differences of FA can be observed. The proposed harmonization approach and three conventional methods (the global-wise scaling, the voxel-wise scaling, and the ComBat) are performed on DTI-derived metrics from two sites. During the tract-based spatial statistics, inter-site differences can be removed by the proposed dual GANs method, the voxel-wise scaling, and the ComBat. Among these methods, the proposed method holds the lowest median values in absolute errors and root mean square errors. During the pooling analysis of two sites, Pearson correlation coefficients between FA and the postmenstrual age after harmonization are larger than those before harmonization. The effect sizes (Cohen's d between males and females) are also maintained by the harmonization procedure.
The proposed dual GANs-based harmonization method is effective to harmonize neonatal DTI-derived metrics from different sites. Results in this study further suggest that the GANs-based harmonization is a feasible pre-processing method for pooling analyses in multi-center studies.
The chemoselective hydrogenation of unsaturated carbonyl compounds is one of the most important and challenging chemical processes in the fine chemical synthesis field, where intermetallic compounds ...(IMCs) have attracted extensive interest as efficient catalysts. In this work, we demonstrate the preparation of several Ni–In IMCs (Ni3In, Ni2In, NiIn, and Ni2In3) with a tunable particle size via the utilization of layered double hydroxides (LDHs) precursors that exhibit largely enhanced catalytic activity and selectivity toward the hydrogenation of α,β-unsaturated aldehydes. H2-TPR and semi-in situ XRD measurements reveal a coreduction process in the topotactic transformation of NiIn-LDHs materials to Ni–In IMCs. The catalytic behavior toward various unsaturated carbonyl compounds (e.g., furfural, 1-phenyltanol, crotonaldehyde, and 2-hexenal) can be improved by the modulation of the Ni/In ratio and the particle size of these Ni–In IMCs. For instance, a yield of 99% for the hydrogenation of furfural to furfuryl alcohol was obtained over supported Ni2In catalyst (particle size 5.1 nm, 110 °C, 3 MP, 2 h). The XAFS characterization and DFT calculation further reveal the electron transfer and active-site isolation in Ni–In IMCs, accounting for the largely enhanced hydrogenation selectivity. The control over the activity and selectivity of Ni–In IMCs catalysts makes them promising candidates for the chemoselective hydrogenation of unsaturated carbonyl compounds.
High-quality surface-enhanced Raman scattering (SERS) spectra of aflatoxin (AF) B(1), B(2), G(1) and G(2) have been acquired using silver nanorod (AgNR) array substrates fabricated by oblique angle ...deposition method. Significant vibrational peaks are identified on the argon plasma-cleaned substrates, and those peaks agree very well with the Raman spectra calculated by density function theory (DFT). The concentration-dependent SERS detection is also explored. The relationship between the concentration (C) of different AFs and the SERS intensity (I) of the Raman peak at Δν = 1592 cm(-1) is found to follow the general relationship I = AC(α), with α ranging from 0.32 to 0.46 for the four AFs. The limits of detection (LODs) reach 5 × 10(-5) mol L(-1) for AFB(1), 1 × 10(-4) mol L(-1) for AFB(2), and 5 × 10(-6) mol L(-1) for both AFG(1) and AFG(2) in bulk solution, or 6.17 × 10(-16) mol/1.93 × 10(-4) ng of AFB(1), 1.23 × 10(-15) mol/3.88 × 10(-4) ng for AFB(2), 6.17 × 10(-17) mol/2.03 × 10(-5) ng for AFG(1), and 6.17 × 10(-17) mol/2.04 × 10(-5) ng for AFG(2) per laser spot. Principal component analysis (PCA) is used to successfully differentiate these four different kinds of AFs at different concentrations up to their detection limits. The LODs obtained from PCA agree with the LODs obtained by using peak fitting method. With such a low detection limit and outstanding differentiation ability, we prove the possibility of utilizing the SERS detection system as a platform for highly sensitive mycotoxin detection.
•An EPS-doped CO2-solidified foam concrete (CFC) integrating the solid wastes valorization and CO2 utilization is proposed.•The compressive strength of EPS doped CFC is notably improved (24.3%), ...accompanied by a significant decrease in adsorption, drying shrinkage, and thermal conductivity.•The EPS interface facilitates the formation of scale-like calcite than spindle-like aragonite due to the different crystallization environments.
Two major issues of EPS doped concrete are apparent reduction in compressive strength associated with the presence of EPS-formed artificial defects and ultra-light weight related easy segregation in the mixes, even though the thermal conductivity of composites shows a satisfactory reduction. This paper presents a composite lightweight concrete by introducing EPS into a solid waste (carbide slag and quartz sand tailings) prepared industrial grade γ-C2S-based foam concrete (CFC) to partially replace foam-formed voids. Results show that the partially EPS-substituted CFC with reasonable EPS parameters (Especially 1 mm in diameter and 5 wt% in content) exhibits a notable improvement in compressive strength (24.3%) while accompanied by the reduction in sorptivity, drying shrinkage and thermal conductivity. This is attributed to the fact that the EPS can effectively improve the foam stability by delaying foam drainage velocity due to its hydrophobicity and discrete smooth surface during the pre-curing procedure, which results in a refinement of void morphology and distribution as well as the optimized interfacial transition zone (ITZ). Accompanied by the compact inner surface and optimized ITZ, leading to a lower drying shrinkage, thermal conductivity, and also a reduction in sorptivity due to the increasing of tortuous path for the capillary flow. Moreover, magnesium slag (MS) containing dicalcium silicate mineral phase is also used to prepare MS-based CFC to further reduce costs and achieve the resource utilization of solid waste and a large amount of CO2 storage, which contributes to the sustainable development of CFC.
Subnanometer nanowires (SNWs) refer to nanowires with diameters close to the size of a single crystal cell. SNWs show not only qualitative change in nature compared to the bulk materials or ...nanomaterials with larger size but also show several advantages in assembly and processing due to their polymer‐analog properties. However, the synthesis of SNWs is still a great challenge. Herein, a synthesis method of SNWs assisted by polyoxometalates is developed. Based on this method, several kinds of SNWs are prepared successfully, and the properties of the SNWs can be regulated efficiently and effectively, demonstrating the extensibility of this synthesis method. Among these SNWs, Bi2O3–PMoO SNWs show good photothermal conversion performance and can be processed into freestanding and flexible films through the wet‐spinning method. The Bi2O3–PMoO SNW films show good performance in solar steam generation and seawater desalination. The average stable evaporation rate can reach 1.38 kg m−2 h−1, and the efficiency is ≈91.1% under 1 sun illumination. The concentration of ions in the desalted seawater with the Bi2O3–PMoO SNWs film are reduced by four orders of magnitude, meeting the quality standards of drinking water and potential for practical utilization of solar energy in the seawater desalination.
A method of preparing subnanometer nanowires (SNWs) facilitated by polyoxometalates is developed. Based on this method, several kinds of SNWs are synthesized successfully, and the properties of the SNWs can be regulated effectively through controlling compositions or introducing new elements, demonstrating the extensibility of this synthesis method. It is useful for constructing functional SNWs.
•A general phase-field fracture model of piezoelectric QCs is proposed.•Influence of electric field on the fracture behaviors of QCs is thoroughly studied.•Anisotropic fracture toughness of ...piezoelectric QCs is considered.•Various fracture problems of piezoelectric QCs can be studied based on the PFM.
In this paper, an electro-elastic phase field model is developed for brittle fracture in piezoelectric quasicrystals. The elastic field of quasicrystals is composite of a phonon field and a phason field. The phonon field, phason field and electric field are coupled with each other, and the phonon and electric loadings trigger the variation of both the phonon and phason elastic energies, which then together contribute to crack evolution. The cracks initiation and propagation in piezoelectric quasicrystals under quasi-static mechanical loading and electric loading can be well predicted. Several numerical examples are performed to evaluate the effects of electric field and anisotropic fracture toughness. Simulation results show that the electric field influences the initial force, peak force, fracture displacement and crack path. For the single-edge notched tensile test, the effects of electric field force on the initial force, peak force and fracture displacement are obvious. For the single-edge notched shear test, the electric field force has no effect on the initial force, but it affects the peak force, fracture displacement and crack path. For the porous plate tensile test, a high-intensity electric field can deflect crack substantially resulting in passing through different holes. Further simulation indicates that the anisotropic fracture toughness has a significant effect on peak force, fracture displacement, and crack path. The present model can be used to simulate various fracture problems of piezoelectric quasicrystals.
Artificial synaptic devices are emerging as contenders for next-generation computing systems due to their combined advantages of self-adaptive learning mechanisms, high parallel computation ...capabilities, adjustable memory level, and energy efficiency. Optoelectronic devices are particularly notable for their responsiveness to both voltage inputs and light exposure, making them attractive for dynamic modulation. However, engineering devices with reconfigurable synaptic plasticity and multilevel memory within a singular configuration present a fundamental challenge. Here, we have established an organic transistor-based synaptic device that exhibits both volatile and nonvolatile memory characteristics, modulated through gate voltage together with light stimuli. Our device demonstrates a range of synaptic behaviors, including both short/long-term plasticity (STP and LTP) as well as STP-LTP transitions. Further, as an encoding unit, it delivers exceptional read current levels, achieving a program/erase current ratio exceeding 10
, with excellent repeatability. Additionally, a prototype 4 × 4 matrix demonstrates potential in practical neuromorphic systems, showing capabilities in the perception, processing, and memory retention of image inputs.
For the effective degradation of tetracycline (TC), a facilely prepared magnetic CuFe2O4/g-C3N4 (CFO/g) photocatalyst was successfully constructed. The structure, morphology, composition, optical, ...and magnetic properties of CFO/g were characterized. CFO/g demonstrated excellent photo-Fenton performance of TC in the presence of high-Cl-, NO3−, HCO3−, HPO42−, SO42− and humic acid. Ten cycles of experiments with the removal rate of TC only decreasing by 2.8% confirmed the stability and high activity of CFO/g. The dissolved concentrations of Fe and Cu ions were 0.013 and 0.009 mg L−1, respectively. Its excellent magnetic properties made CFO/g easier to be recycled than traditional catalysts. ·OH and O2·- were proposed to be the main active species in the photo-Fenton system. The CFO/g heterojunction enhanced the separation of photogenerated electron-hole pairs and visible light absorption range. Furthermore, the identification of intermediates suggested that TC degradation was classified into two pathways, and the most critical and rapid degradation was achieved within the first 30 min. The TC and its intermediates did not significantly inhibit the growth activity of Escherichia coli. This research provided a promising application of magnetic photocatalysts in wastewater treatment of pharmaceuticals and personal care products.
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•A magnetic photocatalyst was constructed with an excellent visible light response.•CuFe2O4/g-C3N4 exhibited efficient tetracycline removal under high-salt conditions.•CuFe2O4/g-C3N4 exhibited efficient tetracycline removal in the presence of anions.•Excellent magnetic properties of CuFe2O4/g-C3N4 facilitated its recycling.•Removal mechanism and intermediates of tetracycline were demonstrated.
This paper analyzes the security of the image encryption algorithm based on a two-dimensional (2D) infinite collapse map. The encryption algorithm adopts a permutation–diffusion structure and can ...perform two or more rounds to achieve a higher level of security. By cryptanalysis, it is found that the original diffusion process can be split into a permutation–diffusion structure, which comes after the original permutation, so these two permutations can be merged into one. Then, some theorems about round-down operation are summarized, and the encryption and decryption equations in the diffusion process are deduced and simplified accordingly. Since the chaotic sequences used in encryption algorithm are independent of the plaintext and ciphertext, there are equivalent keys. The original encryption algorithm with single-round, two-round, and multi-round of permutation–diffusion processes is cracked, and the data complexity of the cryptanalysis attacks is analyzed. Numerical simulation is carried out by MATLAB, and the experimental results and theoretical analysis show the effectiveness of the cryptanalysis attacks. Finally, some suggestions for improvement are given to overcome the shortcomings of the original encryption algorithm.
Step‐scheme (S‐scheme) heterojunctions have been extensively studied in photocatalytic carbon dioxide (CO2) reduction due to their excellent charge separation and high redox ability. The built‐in ...electric field at the interface of a S‐scheme heterojunction serves as the driving force for charge transfer, however, the poor interfacial contact greatly restricts the carrier migration rate. Herein, we synthesized the g‐C3N4/Bi19Br3S27 S‐scheme heterostructure through in situ deposition of Bi19Br3S27 (BBS) on porous g‐C3N4 (P‐CN) nanosheets. The C−S bonds formed at the interface help to enhance the built‐in electric field, thereby promoting the charge transfer and separation. As a result, the CO2 reduction reaction performance of 10 %Bi19Br3S27/g‐C3N4 (BBS/P‐CN) reaches 32.78 μmol g−1h−1, which is 341.4 and 18.7 times higher than that of pure BBS and P‐CN, respectively. X‐ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) prove the presence of chemical bonds (C−S) between the P‐CN and BBS. The S‐scheme charge‐transfer mechanism was analyzed via XPS and density functional theory (DFT) calculations. This work provides a new idea for designing heterojunction photocatalysts with interfacial chemical bonds to achieve high charge‐transfer and catalytic activity.
The effective construction of interfacial C−S bond and built‐in electric field in g‐C3N4/Bi19Br3S27 S‐scheme heterojunction improves the separation of photogenerated electrons and holes, resulting excellent CO2 reduction performance.
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