We experimentally realize a universal set of single-bit and two-bit geometric quantum gates by adiabatically controlling solid-state spins in a diamond defect. Compared with the nonadiabatic ...approach, the adiabatic scheme for geometric quantum computation offers a unique advantage of inherent robustness to parameter variations, which is explicitly demonstrated in our experiment by showing that the single-bit gates remain unchanged when the driving field amplitude varies by a factor of 2 or the detuning fluctuates in a range comparable to the inverse of the gate time. The reported adiabatic control technique and its convenient implementation offer a paradigm for achieving quantum computation through robust geometric quantum gates, which is important for quantum information systems with parameter-fluctuation noise such as those from the inhomogeneous coupling or the spectral diffusion.
With the recent development of optomechanics, the vibration in solids, involving collective motion of trillions of atoms, gradually enters into the realm of quantum control. Here, building on the ...recent remarkable progress in optical control of motional states of diamonds, we report an experimental demonstration of quantum teleportation from light beams to vibrational states of a macroscopic diamond under ambient conditions. Through quantum process tomography, we demonstrate average teleportation fidelity (90.6±1.0)%, clearly exceeding the classical limit of 2/3. The experiment pushes the target of quantum teleportation to the biggest object so far, with interesting implications for optomechanical quantum control and quantum information science.
► A novel single-ion conducting polymer electrolyte, lithium polyvinyl alcohol oxalate borate (LiPVAOB), was prepared. ► It is from the reaction of poly(vinyl alcohol) with boric acid, lithium ...hydroxide and oxalic acid. ► The prepared materials act as single-ion polymer electrolytes. ► Their electrochemical window can be stable up to 7V (vs. Li+/Li). ► They are of great attraction for high voltage lithium ion batteries with high energy density.
In this study, a novel single-ion conducting polymer electrolyte, lithium polyvinyl alcohol oxalate borate (LiPVAOB), from the reaction of poly(vinyl alcohol) (PVA) with different molar ratio of boric acid, oxalic acid and lithium carbonate was prepared. The prepared materials were characterized by Fourier transformation infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG), differential thermal analysis (DTA), electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry. Ionic conductivity of these polymer electrolytes from adding an assistant (about 20wt.% propylene carbonate) is dependent on molar ratio of the reactants and can up to 6.11×10−6Scm−1 at ambient temperature. Their electrochemical window can be stable up to 7V (vs. Li+/Li), which is of great attraction for high voltage lithium ion batteries with high energy density.
Abstract Background Exosomes are nanometer-sized vesicles that are released by normal and neoplastic cells. Previous studies have focused on the interaction between tumour-derived exosomes and the ...immune system, as a consequence of immune suppression or enhancement. However, the effects of tumour-derived exosomes on tumour cells themselves have not been well studied. Aims To investigate the effects of gastric cancer exosomes on tumour cell proliferation and the possible mechanisms. Methods By serial centrifugation and sucrose gradient ultracentrifugation, we isolated and purified the exosomes from gastric cancer SGC7901 cells, then viewed them by electron microscopy. Cell proliferation was measured by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide assay. Protein expression was assayed by Western blotting. Results SGC7901-cell-derived exosomes promoted the proliferation of SGC7901 and BGC823 cells. The increase in proliferation induced by exosomes was accompanied by activation of Akt and extracellular-regulated protein kinase, and phosphoinositide 3-kinase or extracellular-regulated protein kinase inhibitor partially reversed the proliferative effect of exosomes. Moreover, the exosome-induced increase in activity of Akt and extracellular-regulated protein kinase coincided with decreased expression of the Casitas B-lineage lymphoma family of ubiquitin ligases. Conclusion Gastric cancer exosomes promoted tumour cell proliferation, at least in part, by activation of PI3K/Akt and mitogen-activated protein kinase/extracellular-regulated protein kinase pathways. The decreased expression of Casitas B-lineage lymphoma proteins might have contributed to the activation of Akt and extracellular-regulated protein kinase.
In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aβ) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and ...neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aβ and mediates Aβ-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aβ. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aβ deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aβ deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing β-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aβ toxicity and would be a novel therapeutic target and biomarker for AD.
SFTS virus (SFTSV) is a novel bunyavirus that causes severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease that occurred in China in recent years, with an average case ...fatality rate of 10–12%. Intervention in the early clinical stage is the most effective measure to reduce the mortality rate of disease. To elucidate the natural course of and immune mechanisms associated with the pathogenesis of SFTSV, 59 laboratory-confirmed SFTS patients in the acute phase, who were hospitalized between October 2010 and September 2011, were enrolled in this study, and the patients sera were dynamically collected and tested for SFTSV viral RNA load, 34 cytokines or chemokines and other related laboratory parameters. All clinical diagnostic factors in the acute phase of SFTS were evaluated and assessed. The study showed that the severity of the disease in 11 (18.6%) patients was associated with abdominal pain (p 0.007; OR = 21.95; 95% CI, 2.32–208.11) and gingival bleeding (p 0.001; OR = 122.11; 95% CI, 6.41–2328). The IP-10, TNF-α, IL-6, IL-10, granzyme B and HSP70 levels were higher over the 7–8 days in severe cases, accompanied by altered AST, CK and LDH levels. HSP70 (p 0.012; OR = 8.29; 95% CI, 1.58–43.40) was independently correlated with the severity of the early acute phase of SFTSV infection. The severity of SFTS can be predicted based on the presence of symptoms such as abdominal pain and gingival bleeding and on the level of HSP70 in the acute phase of the disease.
The router is a key element for a network. We describe a scheme to realize genuine quantum routing of single-photon pulses based on cascading of conditional quantum gates in a Mach-Zehnder ...interferometer and report a proof-of-principle experiment for its demonstration using linear optics quantum gates. The polarization of the control photon routes in a coherent way the path of the signal photon while preserving the qubit state of the signal photon represented by its polarization. We demonstrate quantum nature of this router by showing entanglement generated between the initially unentangled control and signal photons, and confirm that the qubit state of the signal photon is well preserved by the router through quantum process tomography.
Aims
Purification of porcine circovirus type 2 (PCV2) using Gram‐positive enhancer matrix (GEM) surface display technology and immunogenicity evaluation of the purified antigen.
Methods and Results
A ...recombinant bifunctional protein containing a protein anchor domain and a ‘virus anchor’ domain was designed as a protein linker (PL) between PCV2 and GEM particles. By incubating with PL and GEM particles sequentially, PCV2 could be purified and enriched through a simple centrifugation process with GEM surface display technology. Our data showed that one unit (2·5 × 109 particles) of GEM particles with 80 μg PL could purify 100 ml of PCV2‐containing culture supernatant (viral titre: 106·5 TCID50 per ml−1) with a recovery rate up to 99·6%. The impurity removal efficiency of this method, calculated according to decreased total protein content during purification, was approximately 98%. Furthermore, in vivo experimentation showed that piglets immunized with purified PCV2 could elicit strong immune responses to prevent against PCV2 infection.
Conclusion
Porcine circovirus type 2 could be efficiently purified and enriched with GEM display technology via a crucial PL, and the purified PCV2 could elicit effective immune responses against PCV2 infection.
Significance and Impact of the Study
The GEM‐based purification method established here is cost‐efficient and high‐throughput, and may represent a promising large‐scale purification method for PCV2 vaccine production.
To systematically study the influence of loading environment system stiffness (
LESS
) on post-peak stress–strain curves and failure modes of brittle hard rocks, marble and granite specimens are ...tested under uniaxial compression under axial-strain-controlled loading using a brittle hard rock testing system named Stiffman with variable
LESS
. The test results show that the post-peak descending slopes of the stress–strain curves under low
LESS
are steep, and with the increase of the
LESS
, the slopes are gentle. In addition, as
LESS
increases, AE events in the post-peak deformation stage gradually transit from a concentrated distribution near the peak strength to a dispersed distribution in the whole post-peak deformation stage, and the maximum AE rate and the maximum cumulative AE count decrease approximately linearly with the increase of
LESS
. The number of splitting macrocracks and the degree of damage decrease as
LESS
increases, indicating that the post-peak failure process is more stable when
LESS
is high. The mechanism that leads to different post-peak descending slopes of stress–strain curves under different
LESS
is analyzed by comparing the variations of axial stress, axial and lateral strains, rates of axial and lateral strains over time in the loading process, and analyzing the relations between the maximum axial stress drop rate, the average axial strain rate amplitude, the maximum lateral strain rate and
LESS
. Fitting formulas relating
LESS
to the post-peak deformation modulus are established. Finally, pillar stability is discussed based on energy absorption and release considering the post-peak slopes of the pillar and surrounding rock. Considering the influence of
LESS
on the post-peak stress–strain curves of rocks, it is advisable to obtain strength and deformation properties of brittle rocks in line with the field
LESS
so as to provide more accurate parameters for rock engineering design and analysis.
Highlights
Influence of loading environment system stiffness (
LESS
) on post-peak deformation of rock is studied experimentally.
LESS
affects the amount of loading/unloading adjustment by the servo-control system.
Rock dilation is reduced with the increase of
LESS
, which will result in smaller unloading adjustments.
As
LESS
increases, the post-peak stress–strain curve becomes flatter.
We report the first state-independent experimental test of quantum contextuality on a single photonic qutrit (three-dimensional system), based on a recent theoretical proposal Phys. Rev. Lett. 108, ...030402 (2012). Our experiment spotlights quantum contextuality in its most basic form, in a way that is independent of either the state or the tensor product structure of the system.
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