Nuclear-nuclear interaction mediated by a mechanically controlled nitrogen-vacancy-center spin in diamond

We propose a scheme to achieve nuclear-nuclear indirect interactions mediated by a mechanically driven nitrogen-vacancy (NV) center in diamond. Here we demonstrate two-qubit entangling gates and quantum-state transfer between two carbon nuclei in diamond. In such a system, the NV center interacts with a nearby nuclear spin via a dipole-dipole interaction. Under the quantum Zeno condition, the scheme is robust against decoherence caused by coupling between the NV center (nuclear spins) and the environment. Conveniently, precise control of dipole coupling is not required so this scheme is insensitive to fluctuating positions of the nuclear spins and the NV center. Our scheme provides a general blueprint for multi-nuclear-spin gates and for multi-party communication in a polygon geometry with each vertex occupied by a nuclear spin.Comment: 11 pages, 8 figure

G-CSF mobilized PBMCs contribute to the liver function of cirrhotic rats

On the basis of the recently recognized potential of bone marrow stem cells to give rise to hepatocytes, we here investigated the role of G-CSF priming PBMCs played in the liver of cirrhotic rats. The animal model of liver cirrhosis was induced by injecting CCl4 in SD rats, and G-CSF was administered in hematopoietic stem cell mobilization doses. After the liver cirrhosis model was established, the female cirrhotic rats were divided into two groups. Group I only received G-CSF mobilization, group II received G-CSF mobilized PBMCs transplanted from the male cirrhotic rats. PKH26 staining and sex-determining region for the Y-chromosome gene were used to trace the transplanted cells. Liver function related factors were assayed under the animal automatic biochemistry analyzer, and the liver pathological changes were evaluated by HE staining. The comparative liver functions of the two groups were investigated by analysis of two sample t-tests. A P value of <0.05 was considered as significant in all analyses. Our results showed that the transplanted PBMCs could locate in the livers of the female rats. In addition, compared with the group I, rats in group II displayed significant liver improvement in serum ALB, ALT, AST and TBIL (p<0.05). However, the semi-quantitative classification of the liver pathological changes in both groups did not indicate a significant difference (p>0.05). The results indicated that mobilized PBMC transplant could contribute to liver function in cirrhotic livers, which might be an alternative therapy for liver cirrhosis

Hardy's Paradox for High-Dimensional Systems: Beyond Hardy's Limit

Hardy's proof is considered the simplest proof of nonlocality. Here we introduce an equally simple proof that (i) has Hardy's as a particular case, (ii) shows that the probability of nonlocal events grows with the dimension of the local systems, and (iii) is always equivalent to the violation of a tight Bell inequality.Comment: REVTeX4, 5 pages, 1 figure. Typo in Eq. (17) corrected. Ref. [5] complete

Beyond Gisin's Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering

We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin's theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications.Comment: 9 pages, 1 figur

Responses of microbial abundance and enzyme activity in integrated vertical-flow constructed wetlands for domestic and secondary wastewater

Although micro-organisms play a significant role in pollutant removal in constructed wetlands, little is known on the effect of wastewater-quality properties on microbial characteristics. In this study, two groups of integrated vertical-flow constructed wetland microcosms were applied to treat synthetic domestic wastewater and synthetic secondary effluent. The effects of wastewater-quality properties on microbial features were assessed. Results showed that higher values of microbial indicators were observed in the systems with domestic wastewater and in down-flow cells. Redundancy analysis revealed that organic matter concentration and temperature were two critical determinants influencing the microbial features

Beating the Clauser-Horne-Shimony-Holt and the Svetlichny games with Optimal States

We study the relation between the maximal violation of Svetlichny's inequality and the mixedness of quantum states and obtain the optimal state (i.e., maximally nonlocal mixed states, or MNMS, for each value of linear entropy) to beat the Clauser-Horne-Shimony-Holt and the Svetlichny games. For the two-qubit and three-qubit MNMS, we showed that these states are also the most tolerant state against white noise, and thus serve as valuable quantum resources for such games. In particular, the quantum prediction of the MNMS decreases as the linear entropy increases, and then ceases to be nonlocal when the linear entropy reaches the critical points ${2}/{3}$ and ${9}/{14}$ for the two- and three-qubit cases, respectively. The MNMS are related to classical errors in experimental preparation of maximally entangled states.Comment: 7 pages, 3 figures; minor changes; accepted in Physical Review