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Olfactory dysfunction indicates a higher risk of developing dementia. However, the potential structural and functional changes are still largely unknown. A total of 236 participants were enrolled, including 45 Alzheimer's disease (AD) individuals and 191dementia-free individuals. Detailed study methods, comprising neuropsychological assessment and olfactory identification test (University of Pennsylvania smell identification test, UPSIT), as well as structural and functional magnetic resonance imaging (MRI) were applied in this research. The dementia-free individuals were divided into two sub-groups based on olfactory score: dementia-free with olfactory dysfunction (DF-OD) sub-group and dementia-free without olfactory dysfunction (DF-NOD) sub-group. The results were analyzed for subsequent intergroup comparisons and correlations. The cognitive assessment was conducted again three years later. (i) At dementia-free stage, there was a positive correlation between olfactory score and cognitive function. (ii) In dementia-free group, the volume of crucial brain structures involved in olfactory recognition and processing (such as amygdala, entorhinal cortex and basal forebrain volumes) are positively associated with olfactory score. (iii) Compared to the DF-NOD group, the DF-OD group showed a significant reduction in olfactory network (ON) function. (iv) Compared to DF-NOD group, there were significant functional connectivity (FC) decline between PCun_L(R)_4_1 in the precuneus of posterior default mode network (pDMN) and the salience network (SN) in DF-OD group, and the FC values decreased with falling olfactory scores. Moreover, in DF-OD group, the noteworthy reduction in FC were observed between PCun_L(R)_4_1 and amygdala, which was a crucial component of ON. (v) The AD conversion rate of DF-OD was 29.41%, while the DF-NOD group was 12.50%. The structural and functional changes in the precuneus were also observed in AD and were more severe. In addition to the olfactory circuit, the precuneus is a critical structure in the odor identification process, whose abnormal function underlies the olfactory identification impairment of dementia-free individuals. • The olfactory circuit is impaired in olfactory dysfunction among dementia-free. • Abnormal function of precuneus causes olfactory dysfunction in dementia-free. • The precuneus's structure and function also change in Alzheimer's disease. • Olfactory identification ability can be a clinical marker for Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The lateral instability of the couplers seriously threaten the operation safety of 20,000-tonne heavy-haul trains. It is essential to dynamically monitor the coupler yaw angle (CYA) in order to evaluate the operation stability of the train. However, the traditional direct measurement methods for CYA are hindered by the harsh service environment, making it difficult to maintain long-term stability in monitoring. To address these issues, within this paper a multi-task deep multiple kernel extreme learning machine (MT-DMKELM) is developed to quantitatively identify CYA based on the multi-channel relative displacements between the car body and frame (RDCFs). Firstly, the correlation of multi-channel RDCFs is analyzed based on the dynamics model, and the data fusion of strong correlation channels is achieved through an extreme learning machine auto-encoder. Then, a deep network for feature extraction is created by stacking numerous multiple kernel extreme learning machine auto-encoders. Further, the high-level abstract features are input to multiple kernel extreme learning machine for regression estimation of CYA. In addition, the optimal model parameters are obtained using the genetic mutation particle swarm optimization for MT-DMKELM to improve the CYA identification performance. Finally, both dynamics simulation and field test are conducted to confirm the capability of the proposed methods in CYA identification. [ABSTRACT FROM AUTHOR]

Accumulating evidence have demonstrated that cytokines are enriched in tumor-derived extracellular vesicles (EVs) and widely involved in tumorigenesis of various types of carcinomas, including colorectal cancer (CRC). Nevertheless, the functions of cytokines in EVs secreted from colorectal cancer cells remain largely unknown. In the present study, we found that TNF-α was elevated in EVs from CRC patient serum samples and CRC cell lines, of which the expression was associated with aggressive features of colorectal cancer. EV TNF-α secretion is dependent on synaptosome-associated protein 23 (SNAP23). Functional experiments revealed that EV TNF-α promotes CRC cell metastasis via the NF-κB pathway by targeting SNAP23. Mechanistically, SNAP23 was transcriptionally upregulated by EV TNF-α/NF-κB axis to enhance the expression of laminin subunit beta-3 (LAMB3), thereby activating the PI3K/AKT signaling pathway and consequently facilitate CRC progression. Based on our findings, we could conclude that EV TNF-α plays an oncogenic role in CRC progression through SNAP23, which in turn promotes EV TNF-α secretion, suggesting that EV TNF-α/SNAP23 axis may serve as a diagnostic biomarker and potential therapeutic target for CRC. [Display omitted] • Extracellular vesicles-transferred TNF-α played an oncogenic role in colorectal cancer. • TNF-α secretion by extracellular vesicles is regulated by SNAP23 in colorectal cancer. • Extracellular vesicles-transferred TNF-α promoted cancer metastasis via SNAP23. • Extracellular vesicles-transferred TNF-α and SNAP23 form a positive feedback loop. [ABSTRACT FROM AUTHOR]

Copper and silver nanocrystalline chalcogenides, Cu2−xSe, Cu2Te, Ag2Se, and Ag2Te, have been successfully synthesized in a mixture of ethylenediamine and hydrazine hydrate as a solvent at room temperature. Products showed different morphologies, such as nanotubes, nanorods, and nanoparticles. The results indicated that the coordination and chelation abilities of ethylenediamine play an important role in the formation of one-dimensional nanocrystalline binary chalcogenides, and hydrazine hydrate is crucial to the electron transfer in the room temperature reactions. These transition-metal nanocrystalline chalcogenides as prepared were analyzed by X-ray powder diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The UV-Vis absorption properties of these nanocrystals were also measured. [Copyright &y& Elsevier]

[Display omitted] In this paper, the novel 3D hollow Z-scheme heterojunction photocatalysts based on Bi 2 O 3 and CoAl layered double hydroxides (Bi 2 O 3 @CoAl-LDHs) were prepared for efficient visible-light-driven photocatalytic ammonia synthesis. The synthesized nanohybrid exhibits excellent photocatalytic ammonia synthesis performance (48.7 μmol·L−1·h−1) and structural stability, which is primarily attributed to the fact that Z-scheme heterojunction significantly enhanced lifetime of photogenerated carriers (6.22 ns) and transfer efficiency of surface photogenerated electrons (72.5%). Strict control experiments and nitrogen isotope labeling results show that nitrogen and hydrogen in the produced ammonia come from nitrogen and water in the reactant respectively. Electron paramagnetic resonance (EPR) experiments and density functional theory (DFT) calculations further reveal that the built-in electric field due to the difference between Bi 2 O 3 and CoAl-LDHs is the key to constructing the Z-scheme heterojunction. In addition, results of partial density of states (PDOS) show that Co in Bi 2 O 3 @CoAl-LDHs composite is the active site for photocatalytic N 2 fixation. [ABSTRACT FROM AUTHOR]

Nucleic acids detection has become essential in the identification of many infectious diseases and tumors. Conventional qPCR instruments are not suitable for point-of-care Moreover, current miniaturized nucleic acid detection equipment has limited throughput and multiplex detection capabilities, typically allowing the detection of a limited number of samples. Here, we present an affordable, portable, and high-throughput nucleic acid detection device for point-of-care detection. This portable device is approximately 220 × 165 × 140 mm in size and about 3 kg in weight. It can provide stable and accurate temperature control and analyze two fluorescent signals (FAM and VIC) and run 16 samples simultaneously. As a proof of concept, we used the two purified DNA samples from Bordetella pertussis and Canine parvovirus and the results showed good linearity and coefficient of variation. Moreover, this portable device can detect as low as 10 copies and has good specificity. Therefore, our device can provide advantages in real-time diagnosis of high-throughput nucleic acid detection in the field, especially for resource-limited conditions. [Display omitted] • An affordable, portable, and high-throughput nucleic acid detection device was developed. • The device can analyze two fluorescent signals (FAM and VIC) and run 16 samples simultaneously. • This portable device can provide advantages in real-time diagnosis of high-throughput nucleic acid detection in resource-limited conditions. [ABSTRACT FROM AUTHOR]

Novel nanohybrid (β-Ni(OH) 2 -CNTs) obtained by ultrathin Beta-Nickel hydroxide (β-Ni(OH) 2 ) nanosheets grown along multi-walled carbon nanotubes (CNTs) was successfully synthesized and then incorporated into UPR to prepare UPR/β-Ni(OH) 2 -CNTs nanocomposites. Structure of β-Ni(OH) 2 -CNTs nanohybrid was confirmed by X-ray diffraction, scanning electron microscopy measurements. Compared with single CNTs or β-Ni(OH) 2 , the dispersion of β-Ni(OH) 2 -CNTs in UPR was improved greatly. And the UPR/β-Ni(OH) 2 -CNTs nanocomposites exhibited significant improvements in flame retardancy, smoke suppression, and mechanical properties, including decreased peak heat release rate by 39.79%, decreased total heat release by 44.87%, decreased smoke release rate by 29.86%, and increased tensile strength by 12.1%. Moreover, the amount of toxic volatile from UPR nanocomposites decomposition was dramatically reduced, and smoke generation was effectively inhibited during combustion. The dramatical reduction of fire hazards can be ascribed to the good dispersion, the catalytic charring effect of β-Ni(OH) 2 nanosheets and physical barrier effect of stable network structure consisted of β-Ni(OH) 2 and CNTs. [ABSTRACT FROM AUTHOR]

Abstract: P0 glycoprotein is the major structural protein of peripheral nerve myelin where it is thought to modulate inter-membrane adhesion at both the extracellular apposition, which is labile upon changes in pH and ionic strength, and the cytoplasmic apposition, which is resistant to such changes. Most studies on P0 have focused on structure-function correlates in higher vertebrates. Here, we focused on its role in the structure and interactions of frog (Xenopus laevis) myelin, where it exists primarily in a dimeric form. As part of our study, we deduced the full sequence of X. laevis P0 (xP0) from its cDNA. The xP0 sequence was found to be similar to P0 sequences of higher vertebrates, suggesting that a common mechanism of PNS myelin compaction via P0 interaction might have emerged through evolution. As previously reported for mouse PNS myelin, a similar change of extracellular apposition in frog PNS myelin as a function of pH and ionic strength was observed, which can be explained by a conformational change of P0 due to protonation-deprotonation of His52 at P0’s putative adhesive interface. On the other hand, the cytoplasmic apposition in frog PNS myelin, like that in the mouse, remained unchanged at different pH and ionic strength. The contribution of hydrophobic interactions to stabilizing the cytoplasmic apposition was tested by incubating sciatic nerves with detergents. Dramatic expansion at the cytoplasmic apposition was observed for both frog and mouse, indicating a common hydrophobic nature at this apposition. Urea also expanded the cytoplasmic apposition of frog myelin likely owing to denaturation of P0. Removal of the fatty acids that attached to the single Cys residue in the cytoplasmic domain of P0 did not change PNS myelin structure of either frog or mouse, suggesting that the P0-attached fatty acyl chain does not play a significant role in PNS myelin compaction and stability. These results help clarify the present understanding of P0’s adhesion role and the role of its acylation in compact PNS myelin. [Copyright &y& Elsevier]

• A two-level ACMD is developed to detect wheel flats under variable-speed conditions. • L1-ACMD can separate different fault signal modes under severe interferences. • L2-ACMD can achieve high-resolution time-varying characteristic frequency extraction. • The effectiveness of the method is validated by dynamics simulation and experiment. Wheel flat, as a common defect of railway vehicles, can cause large impact forces on both the vehicle and infrastructure components and thus seriously hinder the vehicle running stability and safety. Considering the complex track irregularities and variable-speed conditions, the vehicle vibration responses often contain strong interference signal components and exhibit time-varying frequency contents, which poses severe challenges to wheel flat detection. In this paper, a vehicle-track coupled model considering wheel flats under variable-speed conditions is employed to calculate and analyze the vehicle vibration accelerations at first. Then, according to the vibration characteristics, a two-level adaptive chirp mode decomposition (ACMD) approach is developed for the wheel flat detection. Specifically, in Level 1 of the approach, the ACMD is integrated with a Gini index-based mode selection and regrouping scheme to separate different fault signal modes under strong interferences. Based on the separated signal modes, the high-resolution ACMD-based time-frequency analysis method is applied to accurately extracting the time-varying fault characteristic frequencies and thus achieving the fault detection in Level 2. Both the dynamics simulation and experiment results indicate that the proposed approach can accurately detect wheel flats of small sizes under strong interferences for a variable-speed railway vehicle. [ABSTRACT FROM AUTHOR]