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Therapeutic effect of curcumin derivative GT863 on prion-infected mice

Combining 3D printing technology with customized metal plates for the treatment of complex acetabular fractures: A retrospective study

Purposes The purpose of this study is to evaluate the clinical outcomes of combining 3D printing technology with customized metal plates in the treatment of complex acetabular fractures. Methods A retrospective study was conducted on 42 patients with complex acetabular fractures treated at our hospital between September 1, 2020 and May 31, 2022. The patients were divided into two groups: the conventional group and the 3D printing group, with 21 individuals in each group.The conventional group underwent surgery using traditional surgical techniques, with appropriate bending and adjustment of the metal plates during the procedure. In the 3D printing group, preoperative 3D printing technology was utilized to create a physical model of the fracture, and individualized metal plates were customized based on the model after virtual reduction. Comparison was made between the two groups of patients regarding surgical approach, operative time, instrument handling time, intraoperative blood loss, number of fluoroscopy scans, fracture healing time, quality of fracture reduction postoperatively, hip joint function at 12 months postoperatively, and occurrence of complications during the follow-up period. Results The 3D printing group showed significantly shorter surgical time (124.76±12.89 minutes vs. 174.05±12.51 minutes), instrument operation time (44.57±5.32 minutes vs. 62.9±7.47 minutes), intraoperative blood loss (337.38±51.95 mL vs. 545.24±74.39 mL), and intraoperative fluoroscopy frequency (8.25±1.18 times vs. 10.52±1.6 times) compared to the conventional group (P<0.001). The postoperative fracture reduction quality in the 3D printing group was good in 95.24% (20/21) of cases, significantly higher than the 61.90% (13/21) in the conventional group (P = 0.02). The excellent and good hip function rate in the 3D printing group was 90.48% (19/21), which was also significantly higher than 57.14% (12/21) in the conventional group (P = 0.01). No significant difference was observed between the two groups in fracture healing time (13.95±1.07 weeks vs. 13.81±1.17 weeks) and complication rate (9.52% vs. 28.57%) (P = 0.14; P = 0.24). Conclusion The application of 3D printing technology in conjunction with individualized customization of metal plates for the treatment of complex acetabular fractures can shorten surgical and instrument handling time, reduce intraoperative blood loss, and improve the quality of fracture reduction as well as the recovery of hip joint function.These results provide new insights and technical support for the treatment of complex acetabular fractures.

Microsphere-assisted laser speckle polarimetric microscopy

This paper presents a robust approach to polarimetric microscopy by integrating microsphere-assisted microscopy, dynamic laser speckle analysis (DLSA), and polarimetric imaging. DLSA creatively transforms laser speckle-induced imaging challenges into opportunities, while simultaneously overcoming traditional polarization interpretation difficulties by analyzing sequence-based variations in speckle pattern, caused by the sample’s polarimetric responses during a full polarimetric measurement. The inclusion of a dielectric microsphere (MS) significantly increases the numerical aperture of the microscopy system, enabling the capture of high-frequency spatial information. A proof-of-concept experiment is conducted on a standard holographic diffraction grating sample. Results obtained from several graphical and numerical statistical analyses demonstrate significant improvements with the incorporation of a silica MS, introducing a cost-effective and non-invasive approach with potential applications in various fields requiring high-precision polarimetric microscopy analyses.

Machine learning tools match physician accuracy in multilingual text annotation

Does corporate governance mechanism deter earnings management and enhance readability of annual reports?

This study aims to know the impact of earnings management (accrual, real and total) and corporate governance mechanisms on the readability of annual reports. Additionally, the study also seeks to know the moderating impact of corporate governance mechanisms between earnings management (accruals, real and total) and readability of annual reports. The sample of the study consists 250 listed firms of Pakistan Stock Exchange (PSX) for the period of 2014–2022. The hypotheses are tested using System GMM technique. The results of the study suggest that earnings management (accruals, real and total) has negative and significant impact on readability of annual reports. However, all four corporate governance mechanics have a significantly positive impact on readability of annual reports. Additionally, corporate governance mechanics significantly moderates the relationship between earnings management (accruals, real and total) and the readability of annual reports. This study has practical implications for regulators, investors, and firms. The findings of the study may suggest to the Security Exchange Commission Pakistan that authorities improve readability by requiring companies to use clear, understandable language and include appropriate information in annual reports. Firms listed on PSX need to produce more readable annual reports to make information more concise and clear, using simple and short sentences, and familiar words.

Unintentional doping in PM6:Y6-based solar cells from exposure to the ambient

Organic solar cells based on non-fullerene acceptors (NFAs) hold great potential for low-cost energy production; however, their large-scale manufacturability and long-term stability still pose challenges. In this work, we clarify how the doping concentration in PM6:Y6-based solar cells evolves as a function of time stored in the ambient. Our results show a rapid increase in the doping concentration, reaching 3 × 1016 cm−3 within the first few hours of ambient exposure. After 100 h of exposure to the ambient, the doping concentration saturates, reaching levels up to 1017 cm−3. A variation of the active layer thickness indicates higher doping concentrations in thinner samples. Previous work has shown that doping concentrations on the order of 1017 cm−3 can have a drastic effect on device performance—either positive or negative, depending on other device parameters. Our findings highlight the importance of properly characterizing unintentional doping in organic solar cell devices, not only in pristine devices, but also as a function of device aging.

Correlation between physiological and biochemical variables during short term adequate protein intake combined with resistance exercise in sedentary adults

SC-GROG followed by L+S reconstruction with multiple sparsity constraints for accelerated Golden-angle-radial DCE-MRI

The GRASP (Golden-angle-radial Sparse Parallel MRI) is a contemporary method for reconstructing dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). This method combines the temporal incoherence of stack-of-stars Golden-angle-radial sampling pattern and acceleration capability of parallel MRI (PI) and compressed sensing (CS) for highly accelerated free-breathing DCE-MRI reconstruction. GRASP uses Temporal Total Variation (TV) norm as a sparsity transform to promote sparsity among multi-coil MRI data and Nonlinear Conjugate Gradient (NL-CG) algorithm to obtain an optimal solution. Additionally, GRASP uses NUFFT gridding to map Golden-angle-radial data to Cartesian grid before NL-CG based CS reconstruction. However, major limitations of GRASP include the temporal averaging effect due to Temporal TV, leading to a degradation in the dynamic contrast of DCE-MRI, and a high computational burden/reconstruction time due to repeated NUFFT gridding/degridding in NL-CG reconstruction. This paper introduces a novel approach to address limitations in GRASP reconstruction technique for free-breathing DCE-MRI. The proposed method combines SC-GROG gridding with low-rank plus sparse (L+S) reconstruction using multiple sparsity constraints for accelerated Golden-angle-radial DCE-MRI with improved temporal resolution and dynamic contrast. Monotone FISTA with variable acceleration (MFISTA-VA) is used to optimize the L+S optimization problem. Further, SC-GROG gridding is used to map Golden-angle radial data to Cartesian grid before L+S reconstruction. The proposed method is tested on two different 3T free-breathing in-vivo DCE-MRI datasets. Reconstruction results of the proposed method are evaluated by using: (i) convergence error, (ii) peak and mean values of arterial signal intensity in the selected region of interest (ROI) of DCE MR Images, and (iii) reconstruction time. Results show that the proposed method provides significant improvements in the reconstruction time and dynamic contrast than the conventional Golden-angle-radial DCE-MRI reconstruction techniques (i.e., GRASP, XD-GRASP). Furthermore, convergence analysis shows that integration of MFISTA-VA in L+S reconstruction provides faster convergence compared to conventional L+S reconstruction.

Monte Carlo study of the electron emission yields of germanium

Though extensive experiments have been performed in the past to measure electron emission properties under electron beam bombardment, reliable measured data for clean and smooth surfaces are still lacking for most elemental solids. In this study, we have conducted a comprehensive Monte Carlo simulation to examine electron emission yields, including secondary electron yield (SEY), backscattering coefficient (BSC), and total electron yield (TEY), for germanium. The uncertainties associated with theoretical calculations have also been assessed with a total of 4608 scattering models by considering several dominant factors that can influence the calculated yields, i.e., optical energy loss function dataset, work function data, dielectric function model for electron inelastic scattering, and scattering potential for electron elastic scattering. Our results indicate that the work function value significantly affects the simulated SEY, and the energy loss function dataset and elastic scattering potential moderately influence both SEY and BSC. Our simulated BSC data are somewhat higher than most of the experimental measurements, while the simulated SEY data are mostly lower than the experimental data within the estimated theoretical uncertainty. This study highlights the critical need for establishing an accurate database of electron emission yields using theoretical modeling, considering particularly the unreliability of the previous experimental data caused by surface contamination during measurements.

Tracing the Neovolcanic zone along the sediment-covered regions of the Red Sea Rift

Abstract The Red Sea Rift is an ultra-slow spreading rift filled with Miocene salt and younger sediments. While volcanic features can be observed in exposed areas in the southern Red Sea Rift, evidence of volcanism in the sediment-blanketed regions in the central and northern Red Sea Rift has been lacking, leaving open whether the mid-ocean rift axis continues beneath them. Here, we present new multichannel seismic and high-resolution bathymetric data of these blanketed regions. Our data reveals multiple instances where oceanic crust can be traced beneath the evaporite cover, forming volcanic edifices protruding through the sediment cover. We identify abundant circular depressions in the sediment cover as volcanic craters, which formed by deep-sea explosive volcanism or caldera collapses. The common occurrence of volcanic features in the sediment-covered regions supports the continuous formation of oceanic crust along large parts of the Red Sea Rift.

Publication bias in the social sciences since 1959: Application of a regression discontinuity framework

While publication bias has been widely documented in the social sciences, it is unclear whether the problem aggravated over the last decades due to an increasing pressure to publish. We provide an in-depth analysis of publication bias over time by creating a unique data set, consisting of 12340 test statistics extracted from 571 papers published in 1959-2018 in the Quarterly Journal of Economics. We, further, develop a new methodology to test for discontinuities at the thresholds of significance. Our findings reveal, that, first, in contrast to our expectations, publication bias was already present many decades ago, but that, second, bias patterns notably changed over time. As such, we observe a transition from bias at the 10 percent to bias at the 5 percent significance level. We conclude that these changes are influenced by increasing computational possibilities as well as changes in the acceptance rates of scientific top journals.

An effective strategy to search for 2D piezoelectric materials

Two-dimensional (2D) piezoelectric materials have a great potential for device applications by utilizing their remarkable electromechanical coupling. In this study, we propose a sure independence screening and sparsifying operator algorithm to search for 2D piezoelectric materials, which is culminating in the identification of a novel 2H-MoS2-like crystalline structure. Utilizing first-principles calculations grounded in density-functional theory, we systematically conducted a thorough analysis of their mechanical properties, electronic properties, and piezoelectric responses. The results indicate that 2H-MoS2-like crystalline structures exhibit the most superior piezoelectric characteristics and have an e11 coefficient of up to 5.09 and a d11 coefficient reaching 10.87, showing remarkable piezoelectric performance. Employing Kendall correlation analysis and polynomial regression, we analyzed the relations between physical parameters and piezoelectric properties, yielding empirical equation that encapsulate the piezoelectric nature of this new class of materials, which mostly related to their lattice structures and bandgaps. Then, we investigated the stress, system energy, and piezoelectric response of these materials under various strain conditions, a d11 coefficient reaching 12.07 for WMo3Se8. Our work may broaden the horizon of low-dimensional piezoelectric materials, offering a pathway to tailor materials with desired properties through our proposed effective strategy.

Anisotropy visualisation from X-ray diffraction of biological apatite in mixed phase calcified tissue samples

Abstract X-ray diffraction is widely used to characterise the mineral component of calcified tissue. Broadening of the diffraction peaks yields valuable information on the size of coherently diffracting domains, sometimes loosely described as crystallite size or crystallinity. These domains are markedly anisotropic, hence a single number describing their size is misleading. We present a novel variation on a method for visualising crystallographic anisotropy in X-ray diffraction data. This provides an intuitively interpretable depiction of crystalline domain size and anisotropy. The new method involves creating a polar plot of calculated domain thickness for peaks in a diffractogram versus crystallographic direction. Points with the least error are emphasised. Anisotropic domain dimensions are calculated by refining an ellipsoidal model in a whole pattern fit. These dimensions are then used to overlay an ellipse on the peak broadening plot. This is illustrated by application of the method to calcifications in breast tissue with suspected cancer, which frequently contain whitlockite as well as nanocrystalline apatite. Like most biogenic apatite, this exhibits markedly anisotropic peak broadening. The nature of this anisotropy offers potentially useful information on normal function and pathology of calcified tissue and is a frequently neglected crystallographic feature of these materials.

Two-step growth of crack-free 5 <i>μ</i>m-thick Al0.2Ga0.8N on sapphire substrate with sputtered AlN nucleation layer

For AlGaN-based near ultraviolet laser diodes (UVA LDs) with emission wavelength below 365 nm, there is no such suitable substrate for homoepitaxy to the required AlGaN films. In this study, we proposed a two-step growth (TSG) method of thick Al0.2Ga0.8N layer grown on the sapphire substrate with a sputtered AlN nucleation layer. The influence of growth rate and V/III ratio on the growth mode of an AlGaN layer has been studied in detail. It is found that AlGaN films exhibit larger island size and lower island density with low growth rate and low V/III ratio during the 3D growth stage, which can effectively relax the compressive stress and suppress the dislocation formation of the subsequent thick AlGaN layer. Therefore, a crack-free high-quality 5 μm-thick Al0.2Ga0.8N layer with 85% biaxial relaxation is grown on a sapphire substrate by using the TSG method, revealing the threading dislocation density decreases from 1.2 × 1010 to 6.6 × 108 cm−2. This work paves the way for the realization and improvement of high-performance AlGaN-based UVA emitters.

Establishing the effect of computed tomography reconstruction kernels on the measure of bone mineral density in opportunistic osteoporosis screening

Tunable magnetic phase transition and room temperature magnetocaloric effect in La0.67Ba0.33MnO3 nanoparticles

Critical behaviors and the magnetic properties have been investigated in La0.67Ba0.33MnO3 nanoparticles systematically. We found tunable critical behaviors in a ferromagnetic–paramagnetic (FM–PM) transition. Thermal fluctuation induced finite-size effects in the nanoscale thermodynamic systems result in suppression of FM–PM critical transition temperature (TC) and broadening of singularities due to finite-size thermal fluctuation in the nanoscale thermodynamic system. By fitting the critical behaviors with the particle sizes, we confirmed the finite size induced decreasing of TC in La0.67Ba0.33MnO3. Room temperature magnetocaloric effects with enhanced refrigeration efficiency have been found in the La0.67Ba0.33MnO3 nanoparticle systems. A relative cooling power of 205 J/kg is found around room temperature. The broadening of the critical transition and shift of critical temperature in the nanoparticles made them excellent magnetic refrigeration materials near room temperature.

Pure data correction enhancing remote sensing image classification with a lightweight ensemble model

Mapping the structural–mechanical landscape of amorphous carbon with ReaxFF molecular dynamics

We use ReaxFF molecular dynamics (MD) to investigate the relationship between structural and mechanical properties in bulk and nanostructured amorphous carbon (a-C). The liquid-quench MD method is used to generate isotropic bulk samples with mass densities ranging from 0.96 to 3.29 g/cm3. Structural analysis identifies two types of structures with distinct short- and medium-range order: lower-density sp2-dominated a-C, which is characterized by a bimodal ring-size distribution, and higher-density sp3-dominated tetrahedral amorphous carbon (ta-C), exhibiting a unimodal ring-size distribution. Stress–strain MD simulations and analysis reveal how an atomistic structure impacts elastic properties and post-yield atomic rearrangements. All stretched structures demonstrate elastic isotropy and plasticity driven by a ring-size expansion mechanism reflected in changes in ring statistics. The plastic region is substantially larger in ta-C than in a-C due to the post-yield shift from sp3 to sp2 C dominant bonding. In both a-C and ta-C, ultimate failure occurs when a reactive crack, traversed by long sp chains, forms and propagates predominantly perpendicular to the direction of the applied strain. Oxygen infiltration into the fractured region significantly reduces stress resistance, primarily through the early rupture of long sp chains. MD simulations and analysis are extended to a-C slabs, a-C nanotubes, and partially a-C nanotubes. The latter nanostructure highlights the differences between the elastically isotropic a-C walls, which develop circumferential cracking, and the crystalline walls, which tear along crystallographic directions. These results provide a strong foundation for further computational characterization of a-C materials.

A randomized trial comparing medium cut-off membrane dialyzers with online hemodiafiltration for uremic toxins clearance in hemodialysis patients

Accelerating inverse Kohn–Sham calculations using reduced density matrices

The Ryabinkin–Kohut–Staroverov (RKS) and Kanungo–Zimmerman–Gavini (KZG) methods offer two approaches to find exchange-correlation (XC) potentials from ground state densities. The RKS method utilizes the one- and two-particle reduced density matrices to alleviate any numerical artifacts stemming from a finite basis (e.g., Gaussian- or Slater-type orbitals). The KZG approach relies solely on the density to find the XC potential by combining a systematically convergent finite-element basis with appropriate asymptotic correction on the target density. The RKS method, being designed for a finite basis, offers computational efficiency. The KZG method, using a complete basis, provides higher accuracy. In this work, we combine both methods to simultaneously afford accuracy and efficiency. In particular, we use the RKS solution as an initial guess for the KZG method to attain a significant 3–11× speedup. This work also presents a direct comparison of the XC potentials from the RKS and the KZG method and their relative accuracy on various weakly and strongly correlated molecules, using their ground state solutions from accurate configuration interaction calculations solved in a Slater orbital basis.