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CD33 has been implicated in the pathogenesis of Alzheimer’s disease primarily through its role in inhibiting the clearance of beta-amyloid (Aβ). However, genetic studies yield mixed results and it is unclear whether the impact of CD33 is specific to Alzheimer’s disease or related to broader neurodegenerative processes. Interestingly, CD33 has also been shown to interact with the hepatitis B (HBV) and C viruses (HCV).
Aims
This study aims to investigate the effects of CD33 single-nucleotide polymorphisms (SNPs) on cognitive functions across diverse populations, including healthy controls, individuals with chronic HBV or HCV and those diagnosed with Parkinson’s disease.
Method
We genotyped CD33 SNPs in 563 participants using the Affymetrix platform. Participants’ cognitive functions were cross-sectionally assessed using a neuropsychological test battery spanning six domains.
Results
Our analysis revealed that CD33 SNP variations had no significant cognitive impact on healthy individuals or Parkinson’s disease patients. However, chronic HBV and HCV patients exhibited significant cognitive differences, particularly in memory, related to CD33 SNP genotypes. Moderation analysis indicated a heightened influence of CD33 SNPs on cognitive functions in chronic HBV and HCV individuals. Our data also suggest that inflammation severity may modulate the cognitive effects in hepatitis patients with specific CD33 SNPs.
Conclusions
This study highlights the importance of CD33 SNPs in cognitive outcomes, emphasising their role in the context of chronic viral hepatitis. It contributes to understanding the cognitive profiles influenced by CD33 SNPs and posits CD33’s potential contribution to neurodegenerative disease progression, potentially intensified by HBV/HCV-induced inflammation.
Language comprehension requires integration of multiple cues, but the underlying mechanisms of how accentuation, as a significant prosodic feature, influences the processing of words with different levels of cloze probability remains unclear. This study exploits event-related potentials (ERPs) to examine the processing of accented and unaccented words with high-, medium-, and low-cloze probabilities embedded in the final position of highly constrained contexts during spoken sentence comprehension. Our results indicate that accentuation and cloze probability interact across the N400 and post-N400 positivity (PNP) time windows. Under the accented condition, N400 amplitudes gradually increased as cloze probability decreased. Conversely, under the unaccented condition, PNP amplitudes gradually increased as cloze probability decreased with a frontal distribution. These results suggest that the effect of predictability is influenced by accentuation, which is likely due to the processing speed and depth of the critical words, modulated by the amount of attentional resources allocated to them.
This study presents a novel investigation into the vortex dynamics of flow around a near-wall rectangular cylinder based on direct numerical simulation at $Re=1000$, marking the first in-depth exploration of these phenomena. By varying aspect ratios ($L/D = 5$, $10$, $15$) and gap ratios ($G/D = 0.1$, $0.3$, $0.9$), the study reveals the vortex dynamics influenced by the near-wall effect, considering the incoming laminar boundary layer flow. Both $L/D$ and $G/D$ significantly influence vortex dynamics, leading to behaviours not observed in previous bluff body flows. As $G/D$ increases, the streamwise scale of the upper leading edge (ULE) recirculation grows, delaying flow reattachment. At smaller $G/D$, lower leading edge (LLE) recirculation is suppressed, with upper Kelvin–Helmholtz vortices merging to form the ULE vortex, followed by instability, differing from conventional flow dynamics. Larger $G/D$ promotes the formation of an LLE shear layer. An intriguing finding at $L/D = 5$ and $G/D = 0.1$ is the backward flow of fluid from the downstream region to the upper side of the cylinder. At $G/D = 0.3$, double-trailing-edge vortices emerge for larger $L/D$, with two distinct flow behaviours associated with two interactions between gap flow and wall recirculation. These interactions lead to different multiple flow separations. For $G/D = 0.9$, the secondary vortex (SV) from the plate wall induces the formation of a tertiary vortex from the lower side of the cylinder. Double-SVs are observed at $L/D = 5$. Frequency locking is observed in most cases, but is suppressed at $L/D = 10$ and $G/D = 0.9$, where competing shedding modes lead to two distinct evolutions of the SV.
Machine learning’s integration into reliability analysis holds substantial potential to ensure infrastructure safety. Despite the merits of flexible tree structure and formulable expression, random forest (RF) and evolutionary polynomial regression (EPR) cannot contribute to reliability-based design due to absent uncertainty quantification (UQ), thus hampering broader applications. This study introduces quantile regression and variational inference (VI), tailored to RF and EPR for UQ, respectively, and explores their capability in identifying material indices. Specifically, quantile-based RF (QRF) quantifies uncertainty by weighting the distribution of observations in leaf nodes, while VI-based EPR (VIEPR) works by approximating the parametric posterior distribution of coefficients in polynomials. The compression index of clays is taken as an exemplar to develop models, which are compared in terms of accuracy and reliability, and also with deterministic counterparts. The results indicate that QRF outperforms VIEPR, exhibiting higher accuracy and confidence in UQ. In the regions of sparse data, predicted uncertainty becomes larger as errors increase, demonstrating the validity of UQ. The generalization ability of QRF is further verified on a new creep index database. The proposed uncertainty-incorporated modeling approaches are available under diverse preferences and possess significant prospects in broad scientific computing domains.
Previous studies have investigated whether lexical access in sentence reading is language-selective using interlingual homographs, but have yielded inconsistent results. In this study, event-related potentials were measured when Korean-Chinese bilinguals read the Chinese version of false-cognates (e.g., “放学”, after school) in Chinese sentence contexts that biased the meaning towards the Korean version (e.g., “방학”, school vacation). With the match words as the baseline, Chinese monolinguals elicited similar N400 and P600/LPC effects when reading the false-cognates and mismatch words, whereas Korean-Chinese bilinguals produced a smaller N400 effect for false-cognates than for mismatch words, indicating activation of the Korean version. The P600/LPC effect was observed for false-cognates in bilinguals, reflecting increased integration difficulties or enhanced cognitive control. The study supported the nonselective view and proposed a theoretical extension of the BIA+ model, claiming that bilingual interactive activation might be mediated by shared morphemic representations between languages.
Expert drivers possess the ability to execute high sideslip angle maneuvers, commonly known as drifting, during racing to navigate sharp corners and execute rapid turns. However, existing model-based controllers encounter challenges in handling the highly nonlinear dynamics associated with drifting along general paths. While reinforcement learning-based methods alleviate the reliance on explicit vehicle models, training a policy directly for autonomous drifting remains difficult due to multiple objectives. In this paper, we propose a control framework for autonomous drifting in the general case, based on curriculum reinforcement learning. The framework empowers the vehicle to follow paths with varying curvature at high speeds, while executing drifting maneuvers during sharp corners. Specifically, we consider the vehicle’s dynamics to decompose the overall task and employ curriculum learning to break down the training process into three stages of increasing complexity. Additionally, to enhance the generalization ability of the learned policies, we introduce randomization into sensor observation noise, actuator action noise, and physical parameters. The proposed framework is validated using the CARLA simulator, encompassing various vehicle types and parameters. Experimental results demonstrate the effectiveness and efficiency of our framework in achieving autonomous drifting along general paths. The code is available at https://github.com/BIT-KaiYu/drifting.
A careful theoretical analysis of the excitation of Alfvén eigenmodes (AEs), such as TAE (toroidicity-induced AE) and RSAE (reversed shear AE), by superalfvenic energetic particles is required for reliable predictions of energetic ion relaxation in present day fusion experiments. This includes the evaluation of different AE damping mechanisms including radiative and continuum dampings which are the focus of this study. A recent comprehensive benchmark of different eigenmode solvers including gyrokinetic, gyrofluid and hybrid magenetohydrodynamics (MHD) has shown that employed models may have deficiencies when addressing some of them (Taimourzadeh et al., Nucl. Fusion, vol. 59, 2019, 066006). In this paper, we are studying the radiative and continuum dampings of RSAEs in details which were missing in hybrid NOVA/NOVA-C calculations to prepare a NOVA-C package with a substantial upgrade. Both dampings require the finite Larmor radius (FLR) corrections to AE mode structures to be accounted for. Accurately calculating different damping rates and understanding their parametric dependencies, we resolve the limitation coming out of the perturbative approach. In particular, here, the radiative damping is included perturbatively, whereas the continuum damping is computed non-perturbatively. Our comparison leads to the conclusion that the non-perturbative treatment of the unstable RSAE modes is needed to find the agreement with the gyrokinetic calculations. We expect that the RSAE mode structure modification plays a dominant role in determining the RSAE stability.
In this work, the Riemann–Hilbert (RH) problem is employed to study the multiple high-order pole solutions of the cubic Camassa–Holm (cCH) equation with the term characterizing the effect of linear dispersion under zero boundary conditions and nonzero boundary conditions. Under the reflectionless situation, we generalize the residue theorem and obtain the multiple high-order pole solutions of cCH equation by solving an algebraic system. During the process of establishing the solution of RH problem, to simplify the calculations involving the implicitly expressed of variables (x, t) in the solution, we introduce a new scale (y, t) to ensure the solution of RH problem is explicitly expressed with respect to it. Finally, the exact solutions are obtained for cases involving one high-order pole and N high-order poles.
Isolated multi-MeV $\gamma$-rays with attosecond duration, high collimation and beam angular momentum (BAM) may find many interesting applications in nuclear physics, astrophysics, etc. Here, we propose a scheme to generate such $\gamma$-rays via nonlinear Thomson scattering of a rotating relativistic electron sheet driven by a few-cycle twisted laser pulse interacting with a micro-droplet target. Our model clarifies the laser intensity threshold and carrier-envelope phase effect on the generation of the isolated electron sheet. Three-dimensional numerical simulations demonstrate the $\gamma$-ray emission with 320 attoseconds duration and peak brilliance of $9.3\times 10^{24}$ photons s${}^{-1}$ mrad${}^{-2}$ mm${}^{-2}$ per 0.1$\%$ bandwidth at 4.3 MeV. The $\gamma$-ray beam carries a large BAM of $2.8 \times 10^{16}\mathrm{\hslash}$, which arises from the efficient BAM transfer from the rotating electron sheet, subsequently leading to a unique angular distribution. This work should promote the experimental investigation of nonlinear Thomson scattering of rotating electron sheets in large laser facilities.
To overcome Yb lasing, a kilowatt-level 1535 nm fiber laser is utilized to in-band pump an Er:Yb co-doped fiber (EYDF) amplifier. The output power of a 301 W narrow-linewidth EYDF amplifier operating at 1585 nm, with 3 dB bandwidth of 150 pm and ${M}^2$< 1.4, is experimentally demonstrated. To the best of our knowledge, it is the highest output power achieved in L-band narrow-linewidth fiber amplifiers with good beam quality. Theoretically, a new ion transition behavior among energy levels for in-band pumping EYDF is uncovered, and a spatial-mode-resolved nonlinearity-assisted theoretical model is developed to understand its internal dynamics. Numerical simulations reveal that the reduction in slope efficiency is significantly related to excited-state absorption (ESA). ESA has a nonlinear hindering effect on power scaling. It can drastically lower the pump absorption and slope efficiency with increasing pump power for in-band pumped EYDF amplifiers. Meanwhile, optimized approaches are proposed to improve its power to the kilowatt level via in-band pumping.
A new species of Moniliformis, M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox1 and cox2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis, and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China.
The numerical investigation focuses on the flow patterns around a rectangular cylinder with three aspect ratios ($L/D=5$, $10$, $15$) at a Reynolds number of $1000$. The study delves into the dynamics of vortices, their associated frequencies, the evolution of the boundary layer and the decay of the wake. Kelvin–Helmholtz (KH) vortices originate from the leading edge (LE) shear layer and transform into hairpin vortices. Specifically, at $L/D=5$, three KH vortices merge into a single LE vortex. However, at $L/D=10$ and $15$, two KH vortices combine to form a LE vortex, with the rapid formation of hairpin vortex packets. A fractional harmonic arises due to feedback from the split LE shear layer moving upstream, triggering interaction with the reverse flow. Trailing edge (TE) vortices shed, creating a Kármán-like street in the wake. The intensity of wake oscillation at $L/D=5$ surpasses that in the other two cases. Boundary layer transition occurs after the saturation of disturbance energy for $L/D=10$ and $15$, but not for $L/D=5$. The low-frequency disturbances are selected to generate streaks inside the boundary layer. The TE vortex shedding induces the formation of a favourable pressure gradient, accelerating the flow and fostering boundary layer relaminarization. The self-similarity of the velocity defect is observed in all three wakes, accompanied by the decay of disturbance energy. Importantly, the decrease in the shedding frequency of LE (TE) vortices significantly contributes to the overall decay of disturbance energy. This comprehensive exploration provides insights into complex flow phenomena and their underlying dynamics.
Music and language are unique communication tools in human society, where stress plays a crucial role. Many studies have examined the recognition of lexical stress in Indo-European languages using beat/rhythm priming, but few studies have examined the cross-domain relationship between musical and linguistic stress in tonal languages. The current study investigates how musical stress and lexical stress influence lexical stress recognition in Mandarin. In the auditory priming experiment, disyllabic Mandarin words with initial or final stress were primed by disyllabic words or beats with either congruent or incongruent stress patterns. Results showed that the incongruent condition elicited larger P2 and the late positive component (LPC) amplitudes than the congruent condition. Moreover, the Strong-Weak primes elicited larger N400 amplitudes than the Weak-Strong primes, and the Weak-Strong primes yielded larger LPC amplitudes than the Strong-Weak primes. The findings reveal the neural correlates of the cross-domain influence between music and language during lexical stress recognition in Mandarin.
Responsible leadership (RL) has become a buzz word in the current lexicon of business and politics, but there is still limited agreement on the components, scope, and characteristics. The confusion is rooted, in part, in the dominance of normative perspectives that take RL as a universal phenomenon. However, embedded in a specific culture, RL cannot be understood fully without understanding the moral traditions of that culture. In this article, we used a case study method to explore how RL is understood and practiced in China. Taking the role theory perspective, we conducted in-depth interviews with 9 highly regarded responsible executive leaders and 92 stakeholders in and outside of their companies who were well acquainted with the leaders. Our findings reveal that in China, the moral character of leaders guides them to define and take responsibility for themselves, their employees, companies, and external stakeholders. The five dimensions of RL we identified and the relationships among the dimensions include characteristics that reflect Chinese culture, such as strong sentiment for the nation, self-discipline, developing employees philosophically, and ‘jun zi wu ben’ (a gentleman should focus on fundamental matters). We conclude by discussing the implications of our study for RL research and practice.
The study aimed to examine the effect of social prescribing on improving cognitive performance among community-dwelling older adults, and to explore the potential association between social support and the change of cognitive performance.
Method:
One hundred and eighteen older adults from Changtang community participated in the study and were followed up for three months. Cognitive function was assessed with Hong Kong Brief Cognitive test (HKBC) at baseline and 3-month follow-up. Pre- and post-social prescribing difference in cognitive performance was examined with paired t-test. Multivariate regression analysis was used to explore the potential factors of social support associated with the change of cognitive function.
Results:
Compared with baseline measurement (25.4±4.1), the total score of HKBC improved significantly after three-month social prescribing (26.5±3.6; t=-3.300,P=0.001). Multivariate regression analysis showed that baseline level of social support utilization was associated with the change of cognitive performance. The lower the utilization of social support at baseline, the more the change of cognitive performance due to social prescribing (β= -0.25, 95%CI = - 0.88 ~ -0.05).
Conclusion:
Social prescribing may have a beneficial effect on cognitive function for community older adults. The utilization of social support may be one of the factors associated with its effect on cognitive performance.
Montmorillonite (Mnt)-based solid acids have a wide range of applications in catalysis and adsorption of pollutants. For such solid acids, the acidic characteristic often plays a significant role in these applications. The objective of the current study was to examine the effects of H3PO4-activation and supporting WO3 on the textural structure and surface acidic properties of Mnt. The Mnt-based solid acid materials were prepared by H3PO4 treatment and an impregnation method with a solution of ammonium metatungstate (AMT) and were examined as catalysts in the dehydration of glycerol to acrolein. The catalysts were characterized by nitrogen adsorption-desorption, powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance ultraviolet-visible (DR UV-Vis) spectroscopy, temperature programmed desorption of NH3 (NH3-TPD), diffuse reflectance Fourier-transform infrared (DR FTIR) spectroscopy of adsorbed pyridine, and thermogravimetric (TG) analyses. The phosphoric acid treatment of Mnt created Brönsted and Lewis acid sites and led to increases in specific surface areas, porosity, and acidity. WO3 species influenced total acidity, acid strength, the numbers of Brönsted and Lewis acid sites, and catalytic performances. A high turnover frequency (TOF) value (31.2 h−1) based on a maximal 60.7% yield of acrolein was reached. The correlation of acrolein yield with acidic properties indicated that the cooperative role of Brönsted and Lewis acid sites was beneficial to the formation of acrolein and a little coke deposition (<3.3 wt.%). This work provides a new idea for the design of solid acid catalysts with cooperative Brönsted and Lewis acidity for the dehydration of glycerol.
Dyes are toxic and considered to be extremely hazardous to natural environments. Hence, adsorbents to remove dyes from contaminated water are needed. To develop adsorbents with a high adsorption capacity for different dyes, easy separation, and low cost, a novel dye adsorbent was prepared by activating fly ash with NaOH. The adsorbent morphology, structure, and specific surface area were characterized using scanning electron microscopy, X-ray powder diffraction, and surface area measurements using N2 adsorption-desorption. The adsorption abilities of the synthesized adsorbents were examined based on methylene blue and acid fuchsin adsorption from water. The capabilities of the adsorbents as a function of adsorbent use, dye type, dye concentration, time, and pH were investigated and compared. The results for methylene blue and acid fuchsin adsorption were modeled using pseudo-second order kinetics and the Langmuir adsorption isotherm, respectively. These modified adsorbents synthesized from fly ash may provide a promising solution to purify dye-contaminated waste water with the advantages of high efficiency and low cost.
The demand for flexible grasping of various objects by robotic hands in the industry is rapidly growing. To address this, we propose a novel variable stiffness gripper (VSG). The VSG design is based on a parallel-guided beam structure inserted by a slider from one end, allowing stiffness variation by changing the length of the parallel beams participating in the system. This design enables continuous adjustment between high compliance and high stiffness of the gripper fingers, providing robustness through its mechanical structure. The linear analytical model of the deflection and stiffness of the parallel beam is derived, which is suitable for small and medium deflections. The contribution of each parameter of the parallel beam to the stiffness is analyzed and discussed. Also, a prototype of the VSG is developed, achieving a stiffness ratio of 70.9, which is highly competitive. Moreover, a vision-based force sensing method utilizing ArUco markers is proposed as a replacement for traditional force sensors. By this method, the VSG is capable of closed-loop control during the grasping process, ensuring efficiency and safety under a well-defined grasping strategy framework. Experimental tests are conducted to emphasize the importance and safety of stiffness variation. In addition, it shows the high performance of the VSG in adaptive grasping for asymmetric scenarios and its ability to flexible grasping for objects with various hardness and fragility. These findings provide new insights for future developments in the field of variable stiffness grippers.
Late Paleozoic strata in the southeastern Ordos Basin comprise targeted reservoirs for tight gas exploration. As a typical intracratonic basin, the Ordos Basin is characterized by low-accommodation space and a complex sediment infilling process, which attracts much attention. During the early Permian, the southeast area was fed by sediments from multiple sediment sources, which makes it difficult to identify the pinch-out of the sand bodies and reconstruct the sediment routing system. In this study, we reconstruct the paleo-topography of the late Paleozoic setting using high-resolution 2D and 3D seismic data. Thus, we identify two types of topography: the eastern block is presented as a semiclosed depression, and the western block is observed as a flat platform. Based on detrital zircon U–Pb data and heavy mineral assemblages, we reconstruct the provenance area and show that early Permian sediments originate from the northern margin of the Ordos Basin and from the northern Qinling orogenic belt in the south. By integrating the trace element contents, carbon and oxygen isotope data and sedimentary structure from core samples, we can observe the paleoenvironment and the corresponding facies associations in these blocks. The eastern block was infilled by a prograding delta; the western block was infilled by a tide-dominated delta or a wavy-dominated delta. By using stratigraphic forward modelling, we find that most sediments in the semiclosed setting are progradational and intensely interacted. In contrast, the sediments in the western block present an open setting, infilled and gently interacted. The fine-grained deposits were not easily preserved due to tidal or wave reworking processes in the shallow-water marine setting, and they were transported into deep-water areas. Furthermore, to explore the dominant factors in a pattern of fluvial–deltaic sand bodies formed in the low-accommodation basin, we rebuild the sediment routing system parameters and plot them on a bubble chart. According to the fitness between the depositional volume and the above parameters, we determine the key factors in the routing systems that formed. The results show that the sediment supply has a high relevance to the depositional volume in a semiclosed setting, such as the eastern block, while the terrain height may drive sedimentation in an open marine setting, such as the western block. We demonstrate that two different infill patterns and different sand-body stacking patterns with multiple sediment sources in a low-accommodation basin may serve as a model for similar settings.