We propose a scheme consisting of coupled nanomechanical cantilever resonators and superconducting flux qubits to engineer a parity-time- ( -) symmetric phononic system formed by active and passive modes. The effective gain (loss) of the phonon mode is achieved by the longitudinal coupling of the resonator and the fast dissipative superconducting qubit with a blue-sideband driving (red-sideband driving). A -symmetric to broken- -symmetric phase transition can be observed in both balanced gain-to-loss and unbalanced gain-to-loss cases.
View Article and Find Full Text PDFChemical warfare agents (CWAs) are among the most lethal chemicals known to humans. Thus, developing multifunctional catalysts for highly efficient detoxification of various CWAs is of great importance. In this work, we developed a robust copper tetrazolate metal-organic framework (MOF) catalyst containing a dicopper unit similar to the coordination geometry of the active sites of natural phosphatase and tyrosinase enzymes.
View Article and Find Full Text PDFNitrite and ammonia often coexist in waters. Thus, it is very significant to develop a photocatalytic process for the simultaneous removal of nitrite and ammonia. Herein, zinc ferrite/activated carbon (ZnFeO/AC) was synthesized and characterized by X-ray diffraction spectroscopy, transmission electron microscopy, Raman spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy.
View Article and Find Full Text PDFCerebral ischemia impairs physiological form of synaptic plasticity such as long-term potentiation (LTP). Clinical symptoms of cognitive dysfunction resulting from cerebral ischemia are associated with neuron loss and synaptic function impairment in hippocampus. It has been widely reported that cordycepin displays neuroprotective effect on ameliorating cognitive dysfunction induced by cerebral ischemia.
View Article and Find Full Text PDFNear-infrared (NIR)-response photocatalysts are desired to make use of 44% NIR solar irradiation. A flower-like α-MnO/N-doped graphene (NG) hybrid catalyst was synthesized and characterized by X-ray diffraction spectroscopy, transmission electron microscopy, Raman spectroscopy, UV-vis-NIR diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The flower-like material of α-MnO/NG was oval-shaped with the semi major axis of 140 nm and semi minor axis of 95 nm and the petal thickness of 3.
View Article and Find Full Text PDFCordycepin, an adenosine analogue, has been reported to improve cognitive function. Important roles on learning and memory of adenosine and its receptors, such as adenosine A1 and A2A receptors (A1R and A2AR), also have been shown. Therefore, we assume that the improvement of learning and memory induced by cordycepin is likely related to hippocampal adenosine content and adenosine receptor density.
View Article and Find Full Text PDFA novel Li-ion capacitor based on an activated carbon cathode and a well-dispersed ultrafine TiO nanoparticles embedded in mesoporous carbon nanofibers (TiO@PCNFs) anode was reported. A series of TiO@PCNFs anode materials were prepared via a scalable electrospinning method followed by carbonization and a postetching method. The size of TiO nanoparticles and the mesoporous structure of the TiO@PCNFs were tuned by varying amounts of tetraethyl orthosilicate (TEOS) to increase the energy density and power density of the LIC significantly.
View Article and Find Full Text PDFBackground: Tenuigenin (TEN), a natural product from the Chinese herb Polygala tenuifolia root, has been reported to improve cognitive function and exhibits neuroprotective effects in pharmacological studies of the central nervous system. Synaptic transmission is the essential process of brain physiological functions such as learning and memory formation, and TEN has been shown to facilitate the basic synaptic transmission.
Hypothesis/purpose: Although our previous work has demonstrated that TEN is able to potentiate the basic synaptic transmission, the potential mechanism remains unclear.
GABAB receptor is present at pre- and post-synaptic sites and participates in many brain functions including cognition, reward and anxiety. Although a lot of research has shown that activation or blockade of GABAB receptor may produce different even opposing effects on long-term potentiation (LTP) and cognitive function, there is little information available concerning the effect of GABAB receptor on behavioral LTP, a learning-induced LTP model. Herein, we firstly examined the effects of 2-OH saclofen, a GABAB receptor antagonist, on the induction of behavioral LTP and Y-maze learning performance.
View Article and Find Full Text PDFCordycepin (3'-deoxyadenosine) is the major bioactive component of Cordyceps militaris that has been widely used in oriental countries as a Traditional Chinese Medicine and healthy food for preventing early aging, improving physical performance and increasing lifespan. Cordyceps militaris extracts other than cordycepin have been reported to improve cognitive function. Although cordycepin is one of the most utilized Cordyceps militaris components, it remains unknown whether cordycepin could improve learning and memory.
View Article and Find Full Text PDFEstrogen deficiency is associated with cognitive impairment. Hormone replacement therapy (HRT) has proven to be effective in preventing and reversing the memory and learning deficiencies. However, conventional estrogenic treatment could increase the risks of breast cancer and venous thromboembolism.
View Article and Find Full Text PDFAims: Cordycepin plays an important role in modulating the function of central nervous system (CNS). However, the modulating mechanism is poorly understood. Excitatory synaptic transmission, the essential process in brain physiology and pathology, is critical in the signal integration activities of the CNS.
View Article and Find Full Text PDFUsing a combination of electrophysiological recordings, behavioral tests and local pharmacological administration in hippocampus, we investigated in the present study the effects of nitric oxide (NO) synthase inhibitor N-nitro-l-arginine methyl ester (l-NAME) on the behavioral long-term potentiation (LTP) and maze learning performance in freely moving rats. The results showed as follows: (1) intrahippocampal l-NAME administration led to a defect in maze learning performance of the animals; (2) l-NAME treatment also substantially impaired the induction of the behavioral LTP in perforant pathway to dentate gyrus (PP-DG) pathway induced by maze learning task, while it had no significant effects on basic synaptic transmission in PP-DG pathway; Collectively, these results indicate that NO synthesis may be critical for the behavioral LTP in PP-DG pathway and maze learning performance.
View Article and Find Full Text PDFCordycepin (3'-deoxyadenosine) is the main functional component of Cordycepins militaris, a renowned traditional Chinese medicine, which has been shown to possess anti-tumor, anti-inflammatory, anti-diabetic and neuro-protective effects. However, the effect of cordycepin on the central nervous system (CNS) remains unclear. In this study, the effects of cordycepin on neuronal activity were investigated on the CA1 pyramidal neurons in rat hippocampal brain slices using a whole-cell patch clamp technique.
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