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This article presents a method for the multimode monitoring of combustion stability under different oxy-gas fired conditions based on flame imaging, principal component analysis (PCA), and kernel support vector machine (KSVM) techniques. The images of oxy-gas flames are segmented into premixed and diffused regions through the watershed transform method. The weighted color and texture features of the diffused and premixed regions are extracted and projected into two subspaces using the PCA to reduce the data dimensions and noises. The multi-class KSVM model is finally built based on the flame features in the principal component subspace to identify the operation condition. Two classic multivariate statistic indices, for example, Hotelling’sT2and squared prediction error, are used to assess the normal and abnormal states for the corresponding operation condition. The experimental results obtained on a lab-scale oxy-gas rig show that the weighted color and texture features of the defined diffused and premixed regions are effective for detecting the combustion state and that the proposed PCA-KSVM model is feasible and effective to monitor a combustion process under variable operation conditions. [ABSTRACT FROM AUTHOR]

The development of efficient bifunctional catalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is essential for reducing the cost of hydrogen production by water splitting. Herein, hollow microtubes composed of RuNi 1 Co 1 alloy nanoparticles uniformly embedded in the carbon matrix (RuNi 1 Co 1 @CMT) are prepared through a simple impregnation followed by reduction. Benefiting from the unique mosaic structure and the synergistic effect between Ru and NiCo, RuNi 1 Co 1 @CMT achieves more exposed active sites and improved reaction kinetics. As a consequence, RuNi 1 Co 1 @CMT exhibits considerable catalytic activities with the overpotentials of 78 mV for HER and 299 mV for OER at 10 mA cm -2 in 1 M KOH. In addition, RuNi 1 Co 1 @CMT exhibits excellent stability for up to 30 h in both HER and OER processes at 20 mA cm -2 , which is attributed to the protection of the RuNi 1 Co 1 alloy particles by the carbon layer. Furthermore, the assembled RuNi 1 Co 1 @CMT || RuNi 1 Co 1 @CMT overall water splitting system shows a cell voltage of 1.58 V at 10 mA cm -2 . The density functional theory (DFT) calculations indicate that the addition of Ru can optimize the hydrogen adsorption free energy of Ni and Co sites. Finally, a solar panel-driven water splitting device is built, which can realize green and sustainable hydrogen production. The fabrication of RuNi 1 Co 1 @CMT provides a new way for the preparation of effective alloy nanomaterials for energy storage and conversion., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Previous studies show that 3β-hydroxysterol-Δ24 reductase (DHCR24) has a remarked decline in the brain of AD patients. In brain cholesterol synthetic metabolism, DHCR24 is known as the heavily key synthetase in cholesterol synthesis. Moreover, mutations of DHCR24 gene result in inhibition of the enzymatic activity of DHCR24, causing brain cholesterol deficiency and desmosterol accumulation. Furthermore, in vitro studies also demonstrated that DHCR24 knockdown lead to the inhibition of cholesterol synthesis, and the decrease of plasma membrane cholesterol and intracellular cholesterol level. Obviously, DHCR24 could play a crucial role in maintaining cholesterol homeostasis via the control of cholesterol synthesis. Over the past two decades, accumulating data suggests that DHCR24 activity is downregulated by major risk factors for AD, suggesting a potential link between DHCR24 downregulation and AD pathogenesis. Thus, the brain cholesterol loss seems to be induced by the major risk factors for AD, suggesting a possible causative link between brain cholesterol loss and AD. According to previous data and our study, we further found that the reduced cholesterol level in plasma membrane and intracellular compartments by the deficiency of DHCR24 activity obviously was involved in β-amyloid generation, tau hyperphosphorylation, apoptosis. Importantly, increasing evidences reveal that the brain cholesterol loss and lipid raft disorganization are obviously linked to neuropathological impairments which are associated with AD pathogenesis. Therefore, based on previous data and research on DHCR24, we suppose that the brain cholesterol deficiency/loss might be involved in the pathogenesis of AD., (© 2022. The Author(s).)

It is important to develop novel energy to solve energy shortage and environmental problems. Hydrogen evolution reaction (HER) is envisaged as a viable technology that can be used to develop sustainable clean energy. Herein, we report a catalyst with CoSe 2 -MoSe 2 heterostructure grown on reduced graphene oxide with an optimum Co/Mo proportion of 1:1 (CoSe 2 -MoSe 2 (1-1)/rGO). It exhibits good HER activities in both acidic and alkaline conditions. The CoSe 2 -MoSe 2 (1-1)/rGO shows an overpotential of 107 mV at 10 mA cm -2 with a Tafel slope of 56 mV dec -1 under acidic condition. Meanwhile, CoSe 2 -MoSe 2 (1-1)/rGO also presents an overpotential of 182 mV at 10 mA cm -2 and with a Tafel slope of 89 mV dec -1 under alkaline condition. These impressive performances of the catalyst are mainly due to the excellent electronic transmission capability of rGO and the abundant active sites of CoSe 2 -MoSe 2 heterostructure as well as the optimized hydrogen adsorption energy of CoSe 2 -MoSe 2 interface. The design of CoSe 2 -MoSe 2 (1-1)/rGO provides a meaningful guide for manufacturing electrode in energy storage and conversion., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Solid tumors are usually associated with extracellular acidosis due to their increased dependence on glycolysis and poor vascularization. Cancer cells gradually become adapted to acidic microenvironment and even acquire increased aggressiveness. They are resistant to apoptosis but exhibit increased autophagy that is essential for their survival. We here show that NF- κ B, a master regulator of cellular responses to stress, is upregulated in colorectal cancer cells adapted to acidosis (CRC-AA). NF- κ B is more relied upon for survival in CRC-AA than in their parental cells and drives a robust antioxidant response. Supplementation of antioxidant abolishes the increased sensitivity of CRC-AA to NF- κ B inhibition or depletion, suggesting that NF- κ B supports the survival of CRC-AA by maintaining redox homeostasis. Because SQSTM1/p62 is known to mediate the selective autophagy of GATA4 that augments NF- κ B function, we tested whether the enhanced autophagic flux and consequently the reduction of SQSTM1/p62 in CRC-AA cells could activate the GATA4-NF- κ B axis. Indeed, GATA4 is upregulated in CRC-AA cells and augments the NF- κ B activity that underlies the increased expression of cytokines, inhibition of apoptosis, and reduction of reactive oxygen species. Interestingly, secretory factors derived from HCT15-AA cells, the soluble ICAM-1 in particular, also possess antioxidant cytoprotective effect against acidic stress. Together, our results demonstrate a prosurvival role of the p62-restricted GATA4-NF- κ B axis in cancer cells adapted to acidic microenvironment., Competing Interests: The authors declare that they have no conflict of interest., (Copyright © 2021 Xiaojie Liu et al.)

It is of great significance to develop inexpensive and high-efficiency electrocatalysts for the hydrogen evolution reaction (HER). In this work, we synthesized iron molybdenum selenide (FeSe 2 -MoSe 2 ) loaded on reduced graphene oxide (FeSe 2 -MoSe 2 /rGO) by a one-step hydrothermal method. We further optimized the Fe/Mo ratio and determined the best ratio to be 1-1. In acidic (or alkaline) solution, the optimized FeSe 2 -MoSe 2 (1-1)/rGO has a small Tafel slope of 55 (or 80) mV dec -1 and needs an overpotential of 101 (or 178) mV to achieve 10 mA cm -2 . These good properties are mainly due to the structure of bimetallic selenides combining rGO. Moreover, rGO enhances the electrical conductivity. Furthermore, the synergistic effect between FeSe 2 -MoSe 2 (1-1) and rGO results in better HER performance. Density functional theory (DFT) calculation proves that FeSe 2 -MoSe 2 (1-1)/rGO has a small work function. Based on our reasonable design and analysis, FeSe 2 -MoSe 2 (1-1)/rGO is expected to be an efficient and robust catalyst for large-scale applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Accumulating data suggest that the downregulation of DHCR24 is linked to the pathological risk factors of AD, denoting a potential role of DHCR24 in AD pathogenesis. However, it remains unclear whether the downregulation of DHCR24 affects the abnormal heper-phosphorylation of tau protein, which is involved in tauopathy. In present papers, immunofluorescence and Filipin III fluorescence results showed that DHCR24 knockdown significantly lowered the level of plasma membrane cholesterol and expression level of membrane lipid-raft structural protein caveolin-1; and overexpression of DHCR24 could increase the plasma membrane cholesterol levels and facilitating caveolae structure through increase the expression of caveolin-1. PP2A is the key phosphatase involving in tau phosphorylation, which is localized in cholesterol-dependent caveola/raft lipid domains. Here, the PP2A activity was detected by western blot assay. Interestingly, the level of p-PP2Ac at Y307 (inactive) and p-GSK3β at Y216 (active) in the downstream of the PP2A signal pathway were both significantly increased in silencing DHCR24 SH-SY5Y cells, which denoted an inhibition of the PP2A and activation of GSK3β signaling. Conversely, overexpression of DHCR24 blunted the inhibition effect of PP2A and activation of GSK3β. Besides, in the SH-SY5Y cell lines we demonstrated that DHCR24 knockdown obviously induced hyperphosphorylation of tau at Thr181, Thr231, Ser262, Ser396, and Ser422 Sites. In contrast, DHCR24 overexpression protects neuronal SH-SY5Y cells against the hyperphosphorylation of tau at Thr181, Thr231, Ser262, Ser396, and Ser422 Sites. Furthermore, PP2A activator D-erythro-Sphingosine (DES) also obviously inhibited the hyperphosphorylation of tau induced by DHCR24 knockdown. Collectively, our findings firstly confirmed that DHCR24 knockdown obviously induced abnormal hyperphosphorylation of tau by a novel lipid raft-dependent PP2A signaling. We propose that DHCR24 downregulation led to altered cholesterol synthesis as a potential mechanism in the progression of tau hyperphosphorylation involving in AD and other tauopathies.

As a new family of two-dimensional materials, MXenes have attracted increasing attention in recent years due to their widespread potential applications. In contrast to early transition metals in convention, here we expand the M element of MXene to the rare earth element lutetium. Based on the first-principles density functional calculations, the bare lutetium-based carbide MXene Lu 2 C is determined to be stabilized in the T-type configuration. Furthermore, both fluorine and hydroxyl terminated configurations are found to be semiconductors, and their band gaps are suitable for use in semiconductors and visible and near-infrared optical devices. The Lu 2 C(OH) 2 configuration shows a direct band gap and possesses an ultralow work function of 1.4 eV. Both Lu 2 CT 2 (T = F, OH) MXenes exhibit high carrier mobilities. Particularly, the electron mobility of the Lu 2 C(OH) 2 MXene is found to be anisotropic at room temperature, with values as high as 95.19 × 10 3 and 217.1 × 10 3 cm 2 V -1 ·s -1 in the zigzag and armchair directions, respectively, which makes Lu 2 C(OH) 2 a promising material for nanodevices. Based on these predicted properties, our work widens the range of MXene materials and their applications in semiconducting devices.

MXenes represent a new family of two-dimensional materials that have attracted considerable attention in recent years. Because of the remarkably different structures of Sc2C(OH)2 and Sc2CO2 MXene and their recently reported properties, this study explored the structural evolution and mechanism of chemical conversion between these two MXenes. Using first-principles density functional theory (DFT), the mechanism for dehydrogenation/hydrogenation is investigated by gradually removing/adding surface hydrogen atoms for Sc2C(OH)2/Sc2CO2 supercells. Employing three different supercells (2 × 2 × 1, 3 × 3 × 1 and 4 × 4 × 1), intermediate states Sc2C(OH)xO2-x with varying hydrogen content x (0.0625≤x ≤ 1.94) are obtained. The results show that the trend is to minimize the difference in the number of hydrogen atoms and the distance between them on the two sides of the monolayer. This feature is found to be generally applicable to other functional groups of MXenes during surface conversion. Analysis of these structures shows that all the oxygen, carbon and scandium atoms remain in essentially the same locations as in Sc2C(OH)2 until atoms rearrange in the carbon layer at sufficiently low x. Regarding the electronic properties, the behavior of the rearranged configurations is found to depend on the structure, moving beyond the conventional model of p-type doping induced by dehydrogenation. Bipolar magnetic semiconductors (BMSs) are identified from these rearranged configurations by the inhomogeneous distribution of hydrogen atoms on the different sides and x values approximately in the range of 0.188 ≤ x ≤ 0.812. Findings from this study suggest that the intrinsic spin-polarized semiconducting characteristics of Sc2C(OH)xO2-x are expected to be experimentally observable if samples are prepared as nanoscale flakes. The current results indicate that Sc-based MXene may be a promising material for nanoscale spintronic devices.

Chronic prostatitis is a risk factor for impaired male fertility potential, and anti-sperm antibodies (ASAs) cause the autoimmune disease immune infertility, which has a negative effect on semen parameters. Current studies have investigated the ASA-positive relationship between chronic prostatitis versus normal controls, but have shown inconsistent results. Hence, we systematic searched the PubMed, EMBASE, Science Direct/Elsevier, Medline, and the Cochrane Library up to October 2015 for case-control studies that involved the ASA-positive relationship between chronic prostatitis patients versus normal controls. The meta-analysis was performed with Review Manager and Stata software. After literature search, six studies were identified, including 721 cases of chronic prostatitis and 160 normal controls. Our results illustrated a significant correlation of the ASA-positive relationship between chronic prostatitis patients versus normal controls. The combined odds ratio of the ASA-positive rate in chronic prostatitis patients and normal controls was 3.26 (1.86-5.71). There was also a significant correlation of the ASA-positive relationship between National Institutes of Health (NIH) III versus normal controls, and the combined OR was 2.46 (1.10-5.51). However, there was no significant correlation of the ASA-positive relationship between National Institutes of Health (NIH) II versus normal controls. The present study illustrates that the positive rate of ASAs in chronic prostatitis patients was significantly higher than in the control group, suggesting that chronic prostatitis has a negative effect on male reproductive function. However, studies with larger samples are needed to better illuminate the correlation between ASAs and chronic prostatitis., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Liver cancer is one of the most common and highly malignant cancers in the world. There are no effective therapeutic options if an early liver cancer diagnosis is not achieved. In this work, detection of HepG2 cells by label-free microcantilever array aptasensor was developed. The sensing microcantilevers were functionalized by HepG2 cells-specific aptamers. Meanwhile, to eliminate the interferences induced by the environment, the reference microcantilevers were modified with 6-mercapto-1-hexanol self-assembled monolayers. The aptasensor exhibits high specificity over not only human liver normal cells, but also other cancer cells of breast, bladder, and cervix tumors. The linear relation ranges from 1×10(3) to 1×10(5)cells/mL, with a detection limit of 300 cells/mL (S/N=3). Our work provides a simple method for detection of liver cancer cells with advantages in terms of simplicity and stability., (Copyright © 2015 Elsevier B.V. All rights reserved.)