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The design of efficient, stable and cost-effective electrocatalysts for the hydrogen evolution reaction holds substantial significance in water electrolysis, but it remains challenging. Tremella-like nickel-molybdenum bimetal phosphide encapsulated cobalt phosphide (NiMoP/CoP) with hierarchical architectures has been effectively synthesized on nickel foam (NF) via a straightforward hydrothermal followed by low-temperature phosphating method. Based on the unique structural benefits, it significantly increases the number of redox active centers, enhances the electrical conductivity of materials, and diminishes the ion diffusion path lengths, thereby promoting efficient electrolyte penetration and reducing the inherent resistance. The as-obtained NiMoP/CoP/NF electrocatalyst exhibited remarkable catalytic activity with an ultralow overpotential of 38 mV (10 mA cm−2) and low Tafel slope of 83 mV dec−1. The straightforward synthesis process and exceptional electrocatalytic properties of NiMoP/CoP/NF demonstrate great potential for the HER to replace the precious metal catalyst. [ABSTRACT FROM AUTHOR]

Deployable structures based on origami are widely used in the application of actuators. In this paper, we present a novel family of origami-based deployable structures with constant curvature. Two categories of non-flat-foldable and non-developable degree-4 vertices (NFND degree-4 vertices) are introduced. Pyramid structures are constructed based on the NFND degree-4 vertices. Doubly symmetric and singly symmetric spherical origami tubular cells (SOTCs) are established based on pyramid structures. To construct deployable origami modules using SOTCs, linking units are introduced. The mobility of the SOTCs and origami modules is analyzed using constraint screws. To realize the construction and simulation of deployable structures, kinematic and geometric analyses of the doubly symmetric and singly symmetric SOTCs are performed. Finally, we introduce four cases for deployable structures in spherical actuators based on the combination of multiple origami modules. These case studies demonstrate the potential of these deployable origami structures in the design of spherical actuators. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) and related Tauopathies are characterised by the pathologically hyperphosphorylated and aggregated microtubule‐associated protein Tau, which is accompanied by neuroinflammation mediated by activated microglia. However, the role of Tau pathology in microglia activation or their causal relationship remains largely elusive. Methods: The levels of nucleotide‐binding oligomerisation domain (NOD)‐like receptor pyrin domain containing 3 (NLRP3) acetylation and inflammasome activation in multiple cell models with Tau proteins treatment, transgenic mice with Tauopathy, and AD patients were measured by Western blotting and enzyme‐linked immunosorbent assay. In addition, the acetyltransferase activity of Tau and NLRP3 acetylation sites were confirmed using the test‐tube acetylation assay, co‐immunoprecipitation, immunofluorescence (IF) staining, mass spectrometry and molecular docking. The Tau‐overexpressing mouse model was established by overexpression of human Tau proteins in mouse hippocampal CA1 neurons through the adeno‐associated virus injection. The cognitive functions of Tau‐overexpressing mice were assessed in various behavioural tests, and microglia activation was analysed by Iba‐1 IF staining and [18F]‐DPA‐714 positron emission tomography/computed tomography imaging. A peptide that blocks the interaction between Tau and NLRP3 was synthesised to determine the in vitro and in vivo effects of Tau–NLRP3 interaction blockade on NLRP3 acetylation, inflammasome activation, microglia activation and cognitive function. Results: Excessively elevated NLRP3 acetylation and inflammasome activation were observed in 3xTg‐AD mice, microtubule‐associated protein Tau P301S (PS19) mice and AD patients. It was further confirmed that mimics of 'early' phosphorylated‐Tau proteins which increase at the initial stage of diseases with Tauopathy, including TauT181E, TauS199E, TauT217E and TauS262E, significantly promoted Tau–K18 domain acetyltransferase activity‐dependent NLRP3 acetylation and inflammasome activation in HEK293T and BV‐2 microglial cells. In addition, Tau protein could directly acetylate NLRP3 at the K21, K22 and K24 sites at its PYD domain and thereby induce inflammasome activation in vitro. Overexpression of human Tau proteins in mouse hippocampal CA1 neurons resulted in impaired cognitive function, Tau transmission to microglia and microgliosis with NLRP3 acetylation and inflammasome activation. As a targeted intervention, competitive binding of a designed Tau–NLRP3‐binding blocking (TNB) peptide to block the interaction of Tau protein with NLRP3 inhibited the NLRP3 acetylation and downstream inflammasome activation in microglia, thereby alleviating microglia activation and cognitive impairment in mice. Conclusions: In conclusion, our findings provide evidence for a novel role of Tau in the regulation of microglia activation through acetylating NLRP3, which has potential implications for early intervention and personalised treatment of AD and related Tauopathies. [ABSTRACT FROM AUTHOR]

Reducing the environmental problems caused by nitrogen loss and nitrogen pollution is of great significance. The addition of biochar to soil is a new method for increasing nitrogen interception due to the special structural and physicochemical properties of biochar. The optimal modified biochar was screened out after acid–base modification and batch adsorption test in this paper. And then the effects of different soil and biochar mixing methods on soil physicochemical properties and nitrogen adsorption and retention were explored through soil column leaching test. The results showed that the biochar with a pyrolysis temperature of 700 °C had the best adsorption effect on nitrogen after being modified by 0.1 mol/L HCI, and the adsorption capacity of nitrate nitrogen reached 121.46 mg/g. The adsorption process of ammonia nitrogen and nitrate nitrogen conformed to the Langmuir model and was mainly homogeneous monolayer. After mixing the selected modified biochar with black soil, the pH increased by 4.77%, the content of ammonia nitrogen increased by 4.89%, and the nitrate content increased by 16.62%. In this study, the adsorption effect of biochar on nitrogen in black soil was discussed, so as to explore the optimal use of biochar in soil, which provided some reference basis for the relevant research. [ABSTRACT FROM AUTHOR]

The preparation of an electrocatalyst for the oxygen evolution reaction (OER) with high catalytic activity, good long-term durability and rapid reaction kinetics through interface engineering is of great significance. Herein, we have developed a bimetallic sulfide particle cluster-supported three-dimensional graphene aerogel (FeNiS@GA), which serves as an efficient electrocatalyst for OER, by a one-step hydrothermal method. Profiting from the synergy of the FeNiS particle cluster with high capacitance and GA with its three-dimensional porous nanostructure, FeNiS@GA shows a high specific surface area, large pore volume, low contact resistance, and decreases the electron and ion transport routes. FeNiS@GA exhibits outstanding OER activity (when the current density is 50 mA cm−2, the overpotential is 341 mV), low Tafel slope (63.87 mV dec−1) and remarkable stability in alkaline solutions, outperforming FeNiS, NiS@GA, FeS@GA and RuO2. Due to its simple synthesis process and excellent electrocatalytic performance, FeNiS@GA shows great potential to replace noble metal-based catalysts in practical applications. [ABSTRACT FROM AUTHOR]

Efficient non-noble metal bifunctional electrocatalysts can increase the conversion rate of electric energy in the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Herein, a ball & sheet MoS2/Ni3S2 composite with wide-layer-spacing and high 1T-rich MoS2 is assembled on nickel foam (NF) via a two-step solvothermal method with polymeric sulfur (S-r-DIB) as the sulfur source. The obtained material serves as both the cathode and the anode toward overall water splitting in an alkaline electrolyte. The results proved that the interpenetration of MoS2/Ni3S2-p with a ball and sheet structure increased the material active surface area and exposed more catalytic active sites, which contributed to the penetration of solution and the transfer of charge/hydrion. Meanwhile, two different semiconductors of MoS2 and Ni3S2 along with the presence of ample active sulfur edge sites and few-layer, wide-layer-spacing structures of MoS2 lead to an outstanding electrocatalytic activity. In particular, the electrodes of MoS2/Ni3S2-p only need a battery voltage of 1.55 V at 10 mA cm−2. The bifunctional electrocatalyst MoS2/Ni3S2-p also shows excellent stability at large current densities during the electrochemical test. [ABSTRACT FROM AUTHOR]

The development of multifunctional electrocatalysts with rich resources, excellent performance, and stability is necessary for water splitting to achieve sustainable hydrogen and oxygen production. Herein, we report the preparation of a bifunctional coral-like nanostructured electrocatalyst (p-MoS2/NiS2) by in situ vulcanization of polymeric sulfur with a MoO3/Ni as the precursor. It is exciting that the whole preparation process of the electrocatalyst can be completed in a few hours. The as-fabricated multimetallic sulfide not only exhibits well-defined heterointerfaces and the defect-rich two-dimensional (2D) nanoconfiguration with high conductivity to overcome the poor hydrogen evolution reaction (HER) activity, but also promotes the formation of the 1T phase. The obtained p-MoS2/NiS2 nanostructures exhibit low overpotentials of −115 mV at −10 mA cm–2 and 337 mV at 100 mA cm–2 toward the HER and oxygen evolution reaction (OER), respectively, which surpass most of the previously reported bimetallic sulfide-based electrocatalysts. Benefiting from the stability of the hierarchical heterostructure and the coupling effect between the inner layer of NiS2 and outer layers of MoS2, the p-MoS2/NiS2 catalyst is endowed with high activity for water splitting. It can be used as a bifunctional electrocatalyst for water splitting with a cell voltage of 1.51 V at a current density of 10 mA cm–2. Overall, this work proposes a simple in situ vulcanization method to synthesize MoS2, which expands the interlayer spacing and realizes the coexistence of a metastable structure and metal doping. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is a global public health problem and the most common form of dementia. Due to the failure of many single therapies targeting the two hallmarks, Aβ and Tau, and the multifactorial etiology of AD, there is now more and more interest in nutraceutical agents with multiple effects such as Moringa oleifera (MO) that have strong anti-oxidative, anti-inflammatory, anticholinesterase, and neuroprotective virtues. In this study, we treated APP/PS1 mice with a methanolic extract of MO for four months and evaluated its effect on AD-related pathology in these mice using a multitude of behavioral, biochemical, and histochemical tests. Our data revealed that MO improved behavioral deficits such as anxiety-like behavior and hyperactivity and cognitive, learning, and memory impairments. MO treatment abrogated the Aβ burden to wild-type control mice levels via decreasing BACE1 and AEP and upregulating IDE, NEP, and LRP1 protein levels. Moreover, MO improved synaptic plasticity by improving the decreased GluN2B phosphorylation, the synapse-related proteins PSD95 and synapsin1 levels, the quantity and quality of dendritic spines, and neurodegeneration in the treated mice. MO is a nutraceutical agent with promising therapeutic potential that can be used in the management of AD and other neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Surface electromyography (sEMG) is commonly used to observe the motor neuronal activity within muscle fibers. However, decoding dexterous body movements from sEMG signals is still quite challenging. In this paper, we present a high-density sEMG (HD-sEMG) signal database that comprises simultaneously recorded sEMG signals of intrinsic and extrinsic hand muscles. Specifically, twenty able-bodied participants performed 12 finger movements under two paces and three arm postures. HD-sEMG signals were recorded with a 64-channel high-density grid placed on the back of hand and an 8-channel armband around the forearm. Also, a data-glove was used to record the finger joint angles. Synchronisation and reproducibility of the data collection from the HD-sEMG and glove sensors were ensured. The collected data samples were further employed for automated recognition of dexterous finger movements. The introduced dataset offers a new perspective to study the synergy between the intrinsic and extrinsic hand muscles during dynamic finger movements. As this dataset was collected from multiple participants, it also provides a resource for exploring generalized models for finger movement decoding. Measurement(s) Electromyography Technology Type(s) Surface Electrode Factor Type(s) hand gesture Sample Characteristic - Organism Homo sapiens Sample Characteristic - Environment human house Sample Characteristic - Location China [ABSTRACT FROM AUTHOR]

Co-doped magnetic Mn3O4 was synthesized by the solvothermal method and adopted as an effective catalyst for the degradation of oxytetracycline (OTC) in water. Synergistic interactions between Co-Mn3O4 and Fe3O4 not only resulted in the enhanced catalytic activity through the activation of peroxymonosulfate (PMS) to degrade OTC but also made Fe3O4/Co-Mn3O4 easy to be separated and recovered from aqueous solution. 94.2% of OTC could be degraded within 60 min at an initial OTC concentration of 10 mg L−1, catalyst dosage of 0.2 g L−1, and PMS concentration of 10 mM. The high efficiency of OTC removal was achieved in a wider pH range of 3.0–10.0. Co (II), Co (III), Fe (II), Fe (III), Mn (II), Mn (III), and Mn (IV) on Fe3O4/Co-Mn3O4 were identified as catalytic sites based on XPS analysis. The free radical quenching experiments showed that O2•− radicals and 1O2 played the main role in the degradation process and the catalytic degradation of OTC involved both free radical and non-free radical reactions. Eventually, the intermediates of OTC degradation were examined, and the possible decomposition pathways were proposed. The excellent catalytic performances of Fe3O4/Co-Mn3O4 came from the fact that the large specific surface area could provide abundant active sites for the activation of PMS and the redistribution of inter-atomic charges accelerated the redox reactions of metal ions. The high degradation efficiency and rate constant of OTC in actual water samples indicated that Fe3O4/Co-Mn3O4 had a good practical application potential. [ABSTRACT FROM AUTHOR]

Background: Obesity is a worldwide health problem that has been implicated in many diseases, including Alzheimer's disease (AD). AD is one of the most common neurodegenerative disorders and is characterized by two pathologies, including extracellular senior plaques composed of amyloid-β (Aβ) and intracellular neurofibrillary tangles (NFTs) consisting of abnormally hyperphosphorylated tau. According to current research, a high-fat diet (HFD) could exacerbate Aβ accumulation, oxidative damage, and cognitive defects in AD mice. However, the accurate role of HFD in the pathogenesis of AD is far more unclear.Objective: To explore the accurate role of HFD in the pathogenesis of AD.Methods: Open Field, Barns Maze, Elevated zero-maze, Contextual fear condition, Tail suspension test, western blotting, immunofluorescence, Fluoro-Jade C Labeling, Perls' Prussian blue staining, and ELISA were used.Results: HFD caused nonheme iron overload in the brains of APPswe/PS1dE9 (APP/PS1) mice. Furthermore, the administration of M30 (0.5 mg/kg) for iron chelation once every 2 days per os (p.o.) for 1 month remitted memory deficits caused by HFD in APP/PS1 mice. Notably, a variety of hematological parameters in whole blood had no difference after iron chelation. In addition, iron chelation effectively reduced synaptic impairment in hippocampus and neuronal degeneration in cortex in the HFD-fed APP/PS1 mice. Meanwhile, iron chelation decreased Aβ1-40 and Aβ1-42 level as well as neuroinflammation in HFD-fed APP/PS1 mice.Conclusion: These data enhance our understanding of how HFD aggravates AD pathology and cognitive impairments and might shed light on future preclinical studies. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common neurodegenerative disease with limited therapeutic strategies. Cell cycle checkpoint protein kinase 1 (Chk1) is a Ser/Thr protein kinase which is activated in response to DNA damage, the latter which is an early event in AD. However, whether DNA damage-induced Chk1 activation participates in the development of AD and Chk1 inhibition ameliorates AD-like pathogenesis remain unclarified. Here, we demonstrate that Chk1 activity and the levels of protein phosphatase 2A (PP2A) inhibitory protein CIP2A are elevated in AD human brains, APP/PS1 transgenic mice, and primary neurons with Aβ treatment. Chk1 overexpression induces CIP2A upregulation, PP2A inhibition, tau and APP hyperphosphorylation, synaptic impairments, and cognitive memory deficit in mice. Moreover, Chk1 inhibitor (GDC0575) effectively increases PP2A activity, decreases tau phosphorylation, and inhibits Aβ overproduction in AD cell models. GDC0575 also reverses AD-like cognitive deficits and prevents neuron loss and synaptic impairments in APP/PS1 mice. In conclusion, our study uncovers a mechanism by which DNA damage-induced Chk1 activation promotes CIP2A-mediated tau and APP hyperphosphorylation and cognitive dysfunction in Alzheimer's disease and highlights the therapeutic potential of Chk1 inhibitors in AD. [ABSTRACT FROM AUTHOR]

Rapid and accurate detection of phenolic wastewater from industries has created global concern. Herein, core–shell magnetic cellulose nanocrystal supported MOF (Fe3O4/CNC@ZIF-8) with robust peroxidase-like activity was synthesized with tannic acid as modifier and bridge. The peroxidase-mimic catalytic activity of as-prepared Fe3O4/CNC@ZIF-8 was further investigated using o-phenylenediamine (OPD) as peroxidase substrates in the presence of H2O2. Moreover, the experimental conditions were optimized and the kinetic analysis results showed that Fe3O4/CNC@ZIF-8 had higher affinity towards both the substrate OPD and H2O2 than horseradish peroxidase (HRP). Finally, a phenol colorimetric assay with a linear range of 2–200 µM and a detection limit of 0.316 µM was constructed. The catalytic mechanism of Fe3O4/CNC@ZIF-8 with phenol was further investigated by fluorescence test and the generated ·OH was proved to act a crucial role to produce quinoid radicals. Additionally, the synthesized magnetic material had excellent stability and recyclability and ease to separation. These results suggest that the Fe3O4/CNC@ZIF-8 may be one of the promising candidates as peroxidase mimic for colorimetric detection of phenol. [ABSTRACT FROM AUTHOR]

The design and synthesis of high-performance catalysts for hydrogen evolution reaction (HER) is of significant importance for electrocatalysis reaction. In this study, 0D Ag nanoparticles were successfully loaded onto 2D Ni(OH)2 nanosheets by a one-step hydrothermal method for enhancing the electrocatalytic ability. The special structure of Ni(OH)2 with only 2 wt% Ag on 3D nickel foam (NF) exhibited a high surface area and excellent charge transfer channels. Furthermore, the synergistic effect as well as the transfer of electron density between Ag and Ni(OH)2 contributed to a high HER activity. As a result, Ni(OH)2–Ag/NF exhibited excellent HER performance with an overpotential of 89 mV to obtain a current of 10 mA cm−2 in an alkaline electrolyte, 155 mV lower than that of Ni(OH)2/NF. After 10 hours of stability test and more than 1000 cycles, negligible loss of the initial catalytic activity to drive a current density of 10 mA cm−2 verified excellent stability during the alkaline HER process. This research provides a new idea to integrally construct ultralow noble metal catalysts with outstanding HER performance and results in new advances in the field of hydrogen evolution. [ABSTRACT FROM AUTHOR]

When a person perform daily sports or exercises, his or her actions may not be standard. If the actions are non‐standard, the effect of sports or exercises would degrade seriously. Thus, recognizing non‐standard actions is critical to provide constructive suggestions for daily exercises. In order to recognize actions and correct the non‐standard ones during exercises and sports, we propose a method based on EMG signal to provide exercise suggestions. We first divide each channel of EMG signal into fixed‐size segments in the form of sliding windows, second use short‐time Fourier Transform to convert EMG signal segments as spectrograms, third input the spectrograms into a convolutional neural network to recognize the actions, fourth use a decision tree to determine whether the action is standard or non‐standard and provide exercise suggestions if the action is non‐standard. The experimental results show that the proposed method could identify most of the actions and recognize the non‐standard action. [ABSTRACT FROM AUTHOR]

The body health plays an important metric in people's everyday life, and it directly determines whether people have the ability to preferably contribute to the society. In fact, the physical training is a universal sport to enhance the body health. Therefore, the evaluation and analysis of physical training become particularly significant. With the rapid development and emerging of new techniques and networking paradigms, the traditional offline physical training evaluation and analysis cannot be performed well. Instead, this paper uses Mobile Edge Computing (MEC) and Software-Defined Networking (SDN) to implement the evaluation and analysis of physical training, shortened for MSPT, where MEC is the new computing technique and SDN is the new networking paradigm. The proposed MSPT includes two parts. At first, the physical training data from different mobile devices are migrated into the edge server for computing according to the current condition, in which the game theory is used to complete the task scheduling. Then, SDN is responsible for the global scheduling in the centralized control manner, in which the multigranularity scheduling strategy is used to handle the traffic between the SDN controller and edge computing server. The experiments are driven by OMNet, including three aspects of evaluation, i.e., task offloading of MEC, traffic scheduling of SDN, and performance analysis of physical training, and the results show that the proposed MSPT has better performance than the corresponding baselines. [ABSTRACT FROM AUTHOR]

Few-layer and 1T-rich MoS2 is synthesized by a one-step solvothermal process using a rigid segment-containing polysulfide as a concomitant sulfur source and in situ intercalator. The prepared MoS2 displays superior hydrogen evolution reaction activity, providing a facile and mild approach for the development of high performing MoS2 and other two-dimensional lamellar materials. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been considered as promising platforms for preparing the efficient oxygen evolution reaction (OER) catalysts, but few of them are directly employed as active components due to their poor electrical conductivity. Herein, a lamellar bimetallic MFN (MIL‐53(FeNi)) encapsulated in graphene aerogel‐grafted Ni foam has been developed (denoted as MFN@GA/NF). The graphene aerogel (GA) provides abundant space for the in‐situ growth of MFN and functions as a "bridge" to connect nickel foam (NF) with MFN by virtue of good conductivity. Benefitting from its structural integrity, the obtained hierarchical MFN@GA/NF exhibited excellent OER performances in alkaline media with an overpotential of 250 mV (20 mA cm−2) and 326 mV (200 mA cm−2), as well as remarkable stability in continuous electrolysis for over 100 h. This work provides a new channel for engineering MOF‐based functional materials with featured architectures. [ABSTRACT FROM AUTHOR]

The development of highly efficient, economical, and sustainable electrocatalysts based on non‐noble metals for hydrogen evolution reaction (HER) is of vital significance for large‐scale renewable energy storage. Herein, an effective synthetic strategy for the construction of MoO2 nanoflowers decorated with metallic Cu/Cu2O nanoparticles (NPs) on Ni foam (NF) (Cu2O/MoO2@Cu/NF) with a simple two‐step method is reported. The prepared Cu2O/MoO2@Cu/NF as an electrocatalyst exhibits outstanding reactivity and remarkable stability in alkaline solution. The onset overpotential of Cu2O/MoO2@Cu/NF approaches 0 V. An overpotential as low as 32 mV is obtained to afford a current density of 10 mA cm−2, comparable with Pt/C catalysts. The Tafel slope is low at 40 mV dec−1 as well. The involvement of zero‐valent Cu greatly reduces the resistance. The well‐dispersed Cu/Cu2O NPs on the sphere‐like MoO2 nanoflowers exaggerate the surface area. The ringent channels provide the fast release of evolved bubbles. Furthermore, the enhanced conductivity and large surface area lead to significant activity in HER. Herein, a novel design and facile synthesis of a highly efficient electrocatalyst with catalytic activity that is comparable to a Pt/C catalyst is provided. [ABSTRACT FROM AUTHOR]

Background: Abnormally hyperphosphorylated tau is the major protein of neurofibrillary tangles in Alzheimer's disease. Insulin activates PI3K-AKT signaling and regulates tau phosphorylation. Impaired brain insulin signaling is involved in Alzheimer's disease pathogenesis. However, the effect of peripheral insulin on tau phosphorylation is controversial.Objective: In the present study, we determined the effect of peripheral insulin administration on tau phosphorylation in brain.Methods: We intraperitoneally injected a super physiological dose of insulin to mice and analyzed PI3K-AKT signaling and tau phosphorylation in brains by western blots.Results: We found that peripherally administered insulin activated the PI3K-AKT signaling pathway immediately in the liver, but not in the brain. Tau phosphorylation in the mouse brain was found to be first decreased (15 min) and then increased (30 min and 60 min) after peripheral insulin administration and these changes correlated inversely with body temperature and the level of brain protein O-GlcNAcylation. Maintaining body temperature of mice post peripheral insulin administration prevented the insulin/hypoglycemia-induced tau hyperphosphorylation after peripheral insulin administration.Conclusion: These findings suggest that peripheral insulin can induce tau hyperphosphorylation through both hypothermia and downregulation of brain protein O-GlcNAcylation during hypoglycemia. [ABSTRACT FROM AUTHOR]

The fabrication of cost‐effective and performance‐advanced electrocatalysts is in great requirements for water splitting to achieve sustainable oxygen production. A simple and effective precursor of ZIF‐67 particles mounted on Cu(OH)2 nanorods was induced by a template alignment method. After annealing, hierarchical CoO polyhedron‐decorated CuO/Cu2O (CuOx) nanorods on Cu foam (denoted as CuOx@CoO NRs/CF) were achieved, which displayed the heterojunction in CuOx components, hierarchical configuration and outward active sites. These features, verified by HRTEM, SEM, XPS and EDX, optimized the oxygen evolution reaction (OER) electrocatalyst. Benefiting from its large electrochemical surface area and the synergetic effect between CuOx and CoO, CuOx@CoO NRs/CF exhibited considerable catalytic activity with a low overpotential of 254 mV to obtain a current density of 10 mA cm−2 in alkaline electrolyte and a scarce loss of the initial catalyst activity over 24 h and over 5000 cycles. This work provides a channel to enhance the performance in OER. [ABSTRACT FROM AUTHOR]

A sustained release of anti-infection drugs is beneficial for the reduction of required dressing change times and the protection of the granulation tissue against further infection. In this work, the strategy of encapsulating mesoporous SBA-15 particles in a permeable cellulose membrane (CM) was used in the preparation of antibacterial cellulose based composite membranes to depot store and deliver drugs with prolonged anti-microbial drug release characteristics. It was found that SBA-15 with the protection of phosphate buffered saline prefilled in SBA-15 mesoporous channel could resist strong alkali environment during composite membranes preparation and its mesoporous structure remained intact, which was verified by SEM, TEM and BET results. The resultant cellulose based composite membrane containing 30 wt% SBA-15 (denoted as P-CM-SBA (30%)) had achieved 3.6 wt% drug loading and demonstrated the sustained release of chloramphenicol for 250 h, which was resulted from SBA-15/cellulose structure-inducing two-stage release behavior. Strong antibacterial activity of P-CM-SBA (30%) against S. aureus and E. coli. could last 144 h. In addition, the tensile strength, water vapor transmission rate and swelling properties of P-CM-SBA (30%) conformed to the primary requirements of wound dressing materials. Therefore, cellulose based composite membrane with 30 wt% SBA-15 particles possesses the potential for the application of wound healing. [ABSTRACT FROM AUTHOR]

A nitrogen doped bio-carbon catalyst with high specific surface area and a hierarchical interconnected porous structure was fabricated by an in situ gas-foaming strategy from sodium alginate and ammonium chloride. The optimized catalyst displays a fabulous ORR activity, providing a facile approach for the mass production of metal-free bio-carbon catalysts in fuel cells and metal–air batteries. [ABSTRACT FROM AUTHOR]

In order to develop efficient and earth-abundant catalysts for large-scale hydrogen evolution via water splitting, a Ni/Ni(OH)2 dual composition electrocatalyst was manufactured via a two-step electrodeposition procedure. The stepwise fabricated 3D hierarchical nanoarrays as well as the concurrent dual composition electrodeposition yielded a papillae-like hybrid crystal structure. The high electrochemically active surface area, defect-rich hybrid crystal structure, and synergistic effects of the dual composition provided an elevated catalytic performance. Only 53 mV overpotential was needed to deliver a current density of 10 mA cm−2 with a small Tafel slope of 54.5 mV dec−1 to catalyze the HER in alkaline media. Approximately 81% catalytic activity could be maintained after 20 h of continuous testing, demonstrating long-term stability. Our findings offer an efficient approach to design and fabricate efficient noble-metal-free alkaline HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Two rhodamine B-based Schiff bases (RBF, RBC) with different substituent groups (-F and -COOH) have been synthesized. In order to study the sensing properties of two Schiff bases for metal ions, the interaction of Schiff bases with different metal ions was studied over UV-Vis absorption spectra and photofluorescent spectra. The results show that the RBF is a turn-on fluorescent chemosensor for Al3+ ions with being highly selective and sensitive in ethanol. The value of the fluorescence increase factor shows a good linear relationship with the concentration of Al3+ in the range of 1-9 μM with a detection limit of 0.8 μM. Meanwhile, upon addition of Al3+ or Fe3+ ions, the fluorescence intensity of RBC increased significantly (FFe3+FAl3+=0.77). These studies show that, compared with the carboxyl group (-COOH), the introduction of fluorine atoms (-F) to a rhodamine B-based Schiff base can significantly improve selectivity to Al3+. [ABSTRACT FROM AUTHOR]

To achieve a cost‐effective and performance‐enhanced electrocatalyst for the hydrogen evolution reaction (HER), Mo‐doped Cu/Co hybrid oxides were prepared through the processes of hydrothermal chemistry and dehydration/reduction. Hybrid structures consisting of a polycrystalline hybrid crystal structure and an amorphous structure, and hybrid constituents including at least Cu, Cu2O, CuO, CoO, CuCoO2, and Cu2CoO3 were identified and characterized by using SEM, HR‐TEM, XPS as well as electrochemical analysis. Interestingly, no information of the doped Mo appeared in the XRD patterns. The reasonable deduction is that Mo might be confined in the amorphous area. The highly developed interface, enhanced conductivity, larger active surface area, abundant oxygen vacancies, and redistribution of electrons among these elements resulted in the significantly enhanced electrocatalytic activity. The optimized Mo‐doped hybrid Cu/Co oxide exhibited catalytic activity with an overpotential of 88 mV to obtain a current density of 10 mA cm−2 in alkaline electrolyte with scarce loss of the initial catalyst activity for 28 h and over 5000 cycles. This work may provide a channel to enhance the performance in the HER. Better code of conduct: The Mo‐doped hybrid Cu/Co oxide exhibits significantly enhanced electrocatalytic activity, owing to the highly developed interface, better conductivity, larger active surface area, and abundant oxygen vacancies. [ABSTRACT FROM AUTHOR]

The fabrication of non‐noble element electrocatalysts with comparable catalytic activity with Pt‐based materials is in great requirements for water splitting to achieve sustainable hydrogen production. Cu2S/MoS2 heterojunction nanorod arrays on copper foam were prepared for this purpose. The nitrogen doping was achieved in situ. HRTEM, SEM, XPS and EDX verified the heterojunction interfacial texture and the defect‐rich nanoarray configuration. The heterojunction interfacial texture, the defect rich configuration and the outward active sites optimized the structure required as a high‐efficient hydrogen evolution reaction (HER) electrocatalyst. As a result, the charge transfer resistance of the nanoarrays was estimated to be 5.4 Ω at −200 mV versus RHE, even lower than both the precursors. The electrochemical double layer capacitance was 49.95 mF cm−2, which was higher than both the precursors. The Cu2S/MoS2 heterojunction nanoarrays‐like electrocatalyst exhibited significant performance with a low overpotential (91 mV at 10 mA cm−2) and a small Tafel slope (41 mV dec−1) in alkaline electrolyte with 85.3 % retained ability after 1000 cycle runs. This work paves a road for developing high‐performance HER electrocatalysts. His and HER: Nitrogen doped Cu2S/MoS2 heterojunction nanorod arrays grafted on copper foam in situ have been created for efficient hydrogen evolution reaction. The results showed the remarkably improved catalytic activity by designing and tuning the heterostructure, conductivity and active sites. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is characterized by progressive impairment of learning, memory, and cognitive deficits. Glutamate is the major excitatory neurotransmitter in the central nervous system and plays an important role in learning, memory, and cognition. The homeostasis and reutilization of glutamate are dependent on astrocytic uptake by glutamate transporter-1 (GLT-1) and the subsequent glutamate-glutamine cycle. Increasing evidence showed impairments in GLT-1 expression and uptake activity and glutamate-glutamine cycle in AD. Ceftriaxone (Cef) has been reported to upregulate the expression and uptake of GLT-1. Therefore, the present study was undertaken to explore whether Cef can improve cognitive deficits of APP/PS1 mice in early stage of AD by upregulating GLT-1 expression, and then promoting the glutamate-glutamine cycle. It was shown that Cef treatment significantly alleviated the cognitive deficits measured by Morris water maze test and upregulated GLT-1 protein expression in the hippocampus of APP/PS1 mice. Particularly, the activity of glutamine synthetase (GS) and the protein expression of system N glutamine transporter 1 (SN1), which are the key factors involved in the glutamate-glutamine cycle, were significantly upregulated as well after the Cef treatment. Furthermore, inhibition of GLT-1 uptake activity by dihydrokainic acid, an inhibitor of GLT-1, blocked the Cef-induced improvement on the cognitive deficits, GS activity, and SN1 expression. The above results suggested that Cef could improve cognitive deficits of APP/PS1 mice in early stage of AD by upregulating the GLT-1 expression, GS activity, and SN1 expression, which would lead to stimulating the glutamate-glutamine cycle. [ABSTRACT FROM AUTHOR]

A new 4,5-diazafluorene-based fluorescent chemosensor has been synthesized by Schiff base condensation of 9,9-bis(3,5-dimethyl-4-aminophenyl)-4,5-diazafluorene with salicylaldehyde. The interaction of Schiff base with different metal ions has been studied over photofluorescent spectra. The results showed that Schiff base exhibited 194-fold enhancements in fluorescence at 465 nm after Zn ions. Such fluorescent responses could be detected by naked eye under UV-lamp. The complex solution ( L-Zn) exhibited reversibility with EDTA. [ABSTRACT FROM AUTHOR]

FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core–shell nanospheres. [ABSTRACT FROM AUTHOR]

Hypoxia was shown to be associated with an increased risk of Alzheimer's disease (AD). The effects of hypoxia on the development of AD pathology and spatial memory ability and the possible molecular mechanisms remain poorly understood. In this study, we demonstrate that rats exposed to a hypoxic condition (10% oxygen concentration) for 1, 2, 4 and 8 weeks (6 h each day) displayed spatial memory impairment and increased tau phosphorylation at Ser198/199/202, Thr205, Ser262, Ser396 and Ser404 in the hippocampus. Concomitantly, the levels of Tyr216-phosphorylated glycogen synthase kinase (GSK)-3β (activated form of GSK-3β) and Tyr307-phosphorylated protein phosphatase 2A (inactivated form of PP2A) were significantly increased in the hippocampus of the rats with 1, 2, 4 and 8 weeks of hypoxia exposure, while the levels of methylated PP2A (activated form of PP2A) were significantly decreased in the hippocampus of the rats with 4 and 8 weeks of hypoxia exposure. In addition, the content of malondialdehyde, an indicator of oxidative stress, was elevated, whereas the activity of superoxide dismutase was not significantly changed in the hippocampus of the rats exposed to hypoxia. Taken together, these data demonstrated that hypoxia induced tau hyperphosphorylation and memory impairment in rats, and that the increased tau phosphorylation could be attributed to activation of GSK-3β and inactivation of PP2A. These data suggest that interventions to improve hypoxia may be helpful to prevent the development of AD pathology and cognitive impairment. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We report a facile fabrication of a host-metal-guest coordination-bonding system in a mesostructured Fe3O4/chitosan nanoparticle that can act as a pH-responsive drug-delivery system. The mesostructured Fe3O4/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface-modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe3O4/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH2ZnIIDOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH-responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high-performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe3O4/chitosan is a smart nanovehicle for drug delivery owing to both its pH-responsive nature and relaxation efficiency. [ABSTRACT FROM AUTHOR]

Glycogen synthase kinase-3 beta (GSK-3β) dysfunction may play an essential role in the pathogenesis of psychiatric, metabolic, neurodegenerative diseases, in which oxidative stress exists concurrently. Some studies have shown that GSK-3β activity is up-regulated under oxidative stress. This study evaluated how oxidative stress regulates GSK-3β activity in human embryonic kidney 293 (HEK293)/Tau cells treated with hydrogen peroxide (H2O2). Here, we show that H2O2 induced an obvious increase of GSK-3β activity. Surprisingly, H2O2 dramatically increased phosphorylation of GSK-3β at Ser9, an inactive form of GSK-3β,while there were no changes of phosphorylation of GSK-3β at Tyr216. Moreover, H2O2 led to a transient [Ca2+]i elevation, and simultaneously increased the truncation of GSK-3β into two fragments of 40 kDa and 30 kDa, whereas inhibition of calpain decreased the truncation and recovered the activity of GSK-3β. Furthermore, tau was hyperphosphorylated at Ser396, Ser404, and Thr231, three most common GSK-3β targeted sites after 100 μM H2O2 administration in HEK293/Tau cells, whereas inhibition of calpain blocked the tau phosphorylation. In addition, we found that there were no obvious changes of Cyclin-dependent kinase 5 (CDK5) expression (responsible for tau phosphorylation) and of p35 cleavage, the regulatory subunit of CDK5 in H2O2-treated HEK293/Tau cells. In conclusion, Ca2+-dependent calpain activation leads to GSK-3β truncation, which counteracts the inhibitory effect of Ser9 phosphorylation, up-regulates GSK-3β activity, and phosphorylates tau in H2O2-treated HEK293/Tau cells. [ABSTRACT FROM AUTHOR]

A simple preparation process for the monodispersed pH-sensitive core-shell magnetic microspheres was carried out consisting of chitosan self-assembled on magnetic iron oxide nanoparticles. Meanwhile, glucoamylase was immobilized as a model enzyme on this carrier of FeO/CS microspheres by ionic adsorption. The morphology, inner structure, and high magnetic sensitivity of the resulting magnetic chitosan microspheres were studied, respectively, with a field emission scanning electron microscope (SEM), transmission electron microscope (TEM), FT-IR spectroscopy, thermogravimetric analysis (TGA), and a vibrating sample magnetometer (VSM). Subsequently, the properties of glucoamylase immobilized on the regenerated supports were also investigated by determining storage stability, pH stability, reusability, magnetic response, and regeneration of supports. The results from characterization and determination remarkably indicated that the immobilized glucoamylase obtained presents excellent storage stability, pH stability, reusability, magnetic response, and regeneration of supports. Therefore, this kind of magnetic FeO/CS microspheres with perfect monodispersity should be an ideal support for enzyme immobilization. [ABSTRACT FROM AUTHOR]

Accumulation of unfolded proteins can disturb the functions of the endoplasmic reticulum (ER), leading to ER-stress or unfolded protein response (UPR). Recent data have shown that activation of UPR can be found in postmortem brains of Alzheimer's disease (AD) patients; and biological markers for activation of UPR are abundant in neurons with diffuse phosphorylated tau. Although these observations suggest a linkage between ER-stress and tau pathology, little is known of their relationship. In this study, we found that high levels of phosphorylated PKR-like ER-resident kinase (p-PERK) and phosphorylated eukaryotic initiation factor 2 alpha (p-eIF2α) as markers for activation of UPR in the hippocampus of aged P301L mutant tau transgenic mice. The immunoreactivity of p-PERK was found to co-localize with that of phosphorylated tau. We then hypothesized that phosphorylation of tau could induce ER-stress and vice versa in promoting AD-like pathogenesis. By using the protein phosphatase 2A inhibitor okadaic acid (OA) as an inducer for phosphorylation of tau, we found that primary cultures of rat cortical neurons treated with OA triggered UPR as indicated by increased levels of p-PERK and p-eIF2α, splicing of mRNA for xbp-1 and elevated levels of mRNA for GADD153. On the other hand, thapsigargin as an ER-stress inducer stimulated phosphorylation of tau at Thr231, Ser262 and Ser396. Thapsigargin also induced activation of caspase-3 and cleavage of tau. These findings suggested that ER-stress and hyperphosphorylation of tau could be induced by each other to form a vicious cycle to propagate AD-like neurodegeneration. [ABSTRACT FROM AUTHOR]

Accumulation of unfolded proteins can disturb the functions of the endoplasmic reticulum (ER), leading to ER-stress or unfolded protein response (UPR). Recent data have shown that activation of UPR can be found in postmortem brains of Alzheimer's disease (AD) patients; and biological markers for activation of UPR are abundant in neurons with diffuse phosphorylated tau. Although these observations suggest a linkage between ER-stress and tau pathology, little is known of their relationship. In this study, we found that high levels of phosphorylated PKR-like ER-resident kinase (p-PERK) and phosphorylated eukaryotic initiation factor 2 alpha (p-eIF2α) as markers for activation of UPR in the hippocampus of aged P301L mutant tau transgenic mice. The immunoreactivity of p-PERK was found to co-localize with that of phosphorylated tau. We then hypothesized that phosphorylation of tau could induce ER-stress and vice versa in promoting AD-like pathogenesis. By using the protein phosphatase 2A inhibitor okadaic acid (OA) as an inducer for phosphorylation of tau, we found that primary cultures of rat cortical neurons treated with OA triggered UPR as indicated by increased levels of p-PERK and p-eIF2α, splicing of mRNA for xbp-1 and elevated levels of mRNA for GADD153. On the other hand, thapsigargin as an ER-stress inducer stimulated phosphorylation of tau at Thr231, Ser262 and Ser396. Thapsigargin also induced activation of caspase-3 and cleavage of tau. These findings suggested that ER-stress and hyperphosphorylation of tau could be induced by each other to form a vicious cycle to propagate AD-like neurodegeneration. [ABSTRACT FROM AUTHOR]

Brain iron deposition has been proposed to play an important role in the pathophysiology of Alzheimer disease (AD). The aim of this study was to investigate the correlation of brain iron accumulation with the severity of cognitive impairment in patients with AD by using quantitative MR relaxation rate R2′ measurements. Fifteen patients with AD, 15 age- and sex-matched healthy controls, and 30 healthy volunteers underwent 1.5T MR multi-echo T2 mapping and T2* mapping for the measurement of transverse relaxation rate R2′ (R2′=R2*−R2). We statistically analyzed the R2′ and iron concentrations of bilateral hippocampus (HP), parietal cortex (PC), frontal white matter (FWM), putamen (PU), caudate nucleus (CN), thalamus (TH), red nucleus (RN), substantia nigra (SN), and dentate nucleus (DN) of the cerebellum for the correlation with the severity of dementia. Two-tailed t-test, Student-Newman-Keuls test (ANOVA) and linear correlation test were used for statistical analysis. In 30 healthy volunteers, the R2′ values of bilateral SN, RN, PU, CN, globus pallidus (GP), TH, and FWM were measured. The correlation with the postmortem iron concentration in normal adults was analyzed in order to establish a formula on the relationship between regional R2′ and brain iron concentration. The iron concentration of regions of interest (ROI) in AD patients and controls was calculated by this formula and its correlation with the severity of AD was analyzed. Regional R2′ was positively correlated with regional brain iron concentration in normal adults ( r=0.977, P<0.01). Iron concentrations in bilateral HP, PC, PU, CN, and DN of patients with AD were significantly higher than those of the controls ( P<0.05); Moreover, the brain iron concentrations, especially in parietal cortex and hippocampus at the early stage of AD, were positively correlated with the severity of patients' cognitive impairment ( P<0.05). The higher the R2′ and iron concentrations were, the more severe the cognitive impairment was. Regional R2′ and iron concentration in parietal cortex and hippocampus were positively correlated with the severity of AD patients' cognitive impairment, indicating that it may be used as a biomarker to evaluate the progression of AD. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of tyrosine kinase Src on Tyrosine 307(Y307) phosphorylation, protein phosphatase 2A (PP2A) activity, and on tau phosphorylation. Specific Src siRNA was transfected into cultured mouse neuroblastoma N2a cells to inhibit the expression of Src protein, and the phosphorylation levels of PP2A Y307 and tau at different sites, as well as PP2A activity were detected at different time points after siRNA transfection. Twelve hours after siRNA transfection, the protein level of Src was dramatically decreased, with decreased PP2A Y307 phosphorylation. However, the total PP2A protein level was also decreased, together with a decreased PP2A activity. Tau was hyperphosphorylated at the Ser198/199/202 sites. Multiple factors may be involved in the cellular regulation of PP2A activity. Inhibiting Src expression could induce inactivation of PP2A and tau hyperphosphorylation. [ABSTRACT FROM AUTHOR]

We previously reported that the injection of okadaic acid (OA) into the Meynert nucleus basalis of rats induced spatial memory deficits. The present study was designed to further explore the underlying mechanisms. We found that the level of acetylcholine (Ach) in the hippocampus significantly decreased 24 h after injection of OA into the Meynert nucleus basalis of rats. Simultaneously, spatial memory deficit, PP-2A inhibition and tau hyperphosphorylation at Ser-198/Ser-199/Ser-202 (Tau-1 epitope) and Ser-396/Ser-404 (PHF-1 epitope) were observed. With the restoration of hippocampus Ach to normal levels at 48 and 72 h after the injection, the spatial memory deficits, PP-2A inhibition and tau hyperphosphorylation were reversed. It is suggested that injection of OA into the Meynert nucleus basalis of rats may impair the hippocampus-dependent spatial memory through damaging the cholinergic projection between the Meynert nucleus basalis and the hippocampus and the selective inhibition of PP-2A and tau hyperphosphorylation may be at least part of the underlying mechanisms. [ABSTRACT FROM AUTHOR]

One of the neuropathological features of Alzheimer’s disease (AD) is the deposition of senile plaques containing β-amyloid (Aβ). There is limited evidence for the treatment to arrest Aβ pathology of AD. In our present study, we tested the effect of coenzyme Q10 (CoQ10), an endogenous antioxidant and a powerful free radical scavenger, on Aβ in the aged transgenic mice overexpressing Alzheimer presenilin 1-L235P (leucine-to-proline mutation at codon 235, 16–17 months old). The treatment by feeding the transgenic mice with CoQ10 for 60 days (1,200 mg kg−1 day−1) partially attenuated Aβ overproduction and intracellular Aβ deposit in the cortex of the transgenic mice compared with the age-matched untreated transgenic mice. Meanwhile, an increased oxidative stress reaction was detected as evidenced by elevated level of malondialdehyde (MDA) and decreased activity of superoxide dismutase (SOD) in the transgenic mice relative to the wild-type mice, and supplementation of CoQ10 partially decreased MDA level and upregulated the activity of SOD. The results indicate that oxidative stress is enhanced in the brain of the transgenic mice, that this enhancement may further promote Aβ42 overproduction in a vicious formation, and that CoQ10 would be beneficial for the therapy of AD. [ABSTRACT FROM AUTHOR]