464 research outputs found
Holographic Storage of Biphoton Entanglement
Coherent and reversible storage of multi-photon entanglement with a multimode
quantum memory is essential for scalable all-optical quantum information
processing. Although single photon has been successfully stored in different
quantum systems, storage of multi-photon entanglement remains challenging
because of the critical requirement for coherent control of photonic
entanglement source, multimode quantum memory, and quantum interface between
them. Here we demonstrate a coherent and reversible storage of biphoton
Bell-type entanglement with a holographic multimode atomic-ensemble-based
quantum memory. The retrieved biphoton entanglement violates Bell's inequality
for 1 microsecond storage time and a memory-process fidelity of 98% is
demonstrated by quantum state tomography.Comment: 5 pages, 4 figures, accepted by Phys. Rev. Let
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Cognitive-enhancing effects of polygalasaponin hydrolysate in aβ(25-35)-induced amnesic mice.
Polygalasaponins are the major active constituents of Polygala tenuifolia exhibiting antiamnesic activity, but their applications are limited due to their toxicities. Evidence showed that the toxicities can be attenuated by hydrolysis. Herein, effects of a hydrolysate of polygalasaponins (HPS) on cognitive impairment induced by Aβ(25-35) were assessed by Morris water maze and step-through passive avoidance tests. The impaired spatial reference memory was improved by HPS (50 and 100 mg/kg). In the acquisition trial of step-through test, HPS (50 and 100 mg/kg) increased the latency into the dark chamber and decreased the error frequency significantly (P < .05). However, no significant change was observed during the retention trial. Additionally, HPS increased the corresponding SOD activities (62.34%, 22.09%) and decreased MDA levels (28.21%, 32.35%) in both cortex and hippocampus as compared to model animals. These results show that HPS may be a useful treatment against amnesia probably via its antioxidant properties.Peer Reviewe
Cognitive-enhancing effects of polygalasaponin hydrolysate in aβ(25-35)-induced amnesic mice.
Polygalasaponins are the major active constituents of Polygala tenuifolia exhibiting antiamnesic activity, but their applications are limited due to their toxicities. Evidence showed that the toxicities can be attenuated by hydrolysis. Herein, effects of a hydrolysate of polygalasaponins (HPS) on cognitive impairment induced by Aβ25−35 were assessed by Morris water maze and step-through passive avoidance tests. The impaired spatial reference memory was improved by HPS (50 and 100mg/kg). In the acquisition trial of step-through test, HPS (50 and 100mg/kg) increased the latency into the dark chamber and decreased the error frequency significantly (P < .05). However, no significant change was observed during the retention trial. Additionally, HPS increased the corresponding SOD activities (62.34%, 22.09%) and decreased MDA levels (28.21%, 32.35%) in both cortex and hippocampus as compared to model animals. These results show that HPS may be a useful treatment against amnesia probably via its antioxidant properties
Researches on Heat Pump System using Rotary Compressor in Electric Vehicle
In China, electric vehicles (EVs) are becoming increasing popular. With several years practical operation experiences, a lot of news reports reveal the existing electrical supplementary heating can dramatically impact the driving range of EVs under cold weather in north China. The high efficient electric heat pump system has become the research hotspot, but previous research show the heat pump operation could supply adequate heating capacity only in mild weather conditions when the working fluid is R134a. Since the user can’t change environment temperature, choose a high pressure working fluid to have better heating performance become a realistic choice. Now the aluminum scroll compressor is wildly used in EVs, but because of the material and structure, it can’t endure the long term high pressure operation. This paper adopted the low cost steel rotary compressor and high pressure working fluid to build the EV heat pump system. The heat pump cycles using R134a, R407c and R290 have been theoretically analyzed; the rotary compressor has been redesigned to respectively apply the R134a, R407c and R290; the heat pump test rig has been build; three combinations (compressor, oil and working fluid) under the same cold weather conditions have been experimentally researched. Results showed the rotary compressor with the high pressure working fluid applied system can generate adequate heating capacity with less energy
Efficient and long-lived quantum memory with cold atoms inside a ring cavity
Quantum memories are regarded as one of the fundamental building blocks of
linear-optical quantum computation and long-distance quantum communication. A
long standing goal to realize scalable quantum information processing is to
build a long-lived and efficient quantum memory. There have been significant
efforts distributed towards this goal. However, either efficient but
short-lived or long-lived but inefficient quantum memories have been
demonstrated so far. Here we report a high-performance quantum memory in which
long lifetime and high retrieval efficiency meet for the first time. By placing
a ring cavity around an atomic ensemble, employing a pair of clock states,
creating a long-wavelength spin wave, and arranging the setup in the
gravitational direction, we realize a quantum memory with an intrinsic spin
wave to photon conversion efficiency of 73(2)% together with a storage lifetime
of 3.2(1) ms. This realization provides an essential tool towards scalable
linear-optical quantum information processing.Comment: 6 pages, 4 figure
Melatonin-related dysfunction in chronic restraint stress triggers sleep disorders in mice
Stress may trigger sleep disorders and are also risk factors for depression. The study explored the melatonin-related mechanisms of stress-associated sleep disorders on a mouse model of chronic stress by exploring the alteration in sleep architecture, melatonin, and related small molecule levels, transcription and expression of melatonin-related genes as well as proteins. Mice undergoing chronic restraint stress modeling for 28 days showed body weight loss and reduced locomotor activity. Sleep fragmentation, circadian rhythm disorders, and insomnia exhibited in CRS-treated mice formed sleep disorders. Tryptophan and 5-hydroxytryptamine levels were increased in the hypothalamus, while melatonin level was decreased. The transcription and expression of melatonin receptors were reduced, and circadian rhythm related genes were altered. Expression of downstream effectors to melatonin receptors was also affected. These results identified sleep disorders in a mice model of chronic stress. The alteration of melatonin-related pathways was shown to trigger sleep disorders
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