Exotic Haldane Superfluid Phase of Soft-Core Bosons in Optical Lattices

We propose to realize an exotic Haldane superfluid (HSF) phase in an extended Bose-Hubbard model on the two-leg ladder (i.e., a two-species mixture of interacting bosons). The proposal is confirmed by means of large-scale quantum Monte Carlo simulations, with a significant part of the ground-state phase diagram being revealed. Most remarkably, the newly discovered HSF phase features both superfluidity and the non-local topological Haldane order. The effects induced by varying the number of legs are furthermore explored. Our results shed light on how topological superfluid emerges in bosonic systems.Comment: 5 pages, 6 figures; accepted for publication in Physical Review B (April 29, 2016

Overview of recent work on self-healing in cementitious materials

Cracks, especially microcracks, in concrete are of paramount importance to the durability and the service life of cementitious composite. However, the self-healing technology, including autogenous healing and autonomous healing, is expected to be one of effective tools to overcome this boring problem. In this paper, we focus on the autogenous healing of concrete material and a few of recent works of autonomous healing are also mentioned. The durability and the mechanical properties improved by the self-healing phenomenon are reviewed from experimental investigation and practical experience. Several aspects of researches, such as autogenous healing capability of an innovative concrete incorporated geo-materials, self-healing of engineered cementitious composite and fire-damaged concrete, effect of mineral and admixtures on mechanism and efficiency of self-healing concrete are summarized to evaluate the presented progresses in the past several years and to outline the perspective for the further developments. Moreover, a special emphasis is given on the analytical models and computer simulation method of the researches of self-healing in cementitious materials.<br><br>Las fisuras, y sobre todo las microfisuras, tienen una gran repercusión en la durabilidad y en la vida útil de los materiales cementantes. Ante este problema, la tecnología de la autorreparación, tanto autógena como autónoma, se presenta como una solución eficaz. El artículo se centra en la reparación autógena del hormigón, así como en algunos trabajos recientes sobre la reparación autónoma. Se describen las mejoras de las propiedades de durabilidad y de resistencia que proporciona la técnica del hormigón autorreparable, tanto desde el punto de vista de la investigación experimental como del de la experiencia práctica. A fin de evaluar los avances logrados en los últimos años y de trazar las grandes líneas de desarrollo futuro, se resumen varios de los aspectos investigados: capacidad de reparación de un hormigón innovador que incorpora geomateriales; autorreparabilidad tanto de los compuestos cementantes tecnológicos como de los hormigones que han sufrido daños por incendio; influencia de los aditivos minerales en el mecanismo y eficacia del hormigón autorreparable. Además, se destaca el papel de los modelos analíticos y los métodos de simulación informática en la investigación de los materiales cementantes autorreparables

Spatio-Temporal Kronecker Compressive Sensing for Traffic Matrix Recovery

A traffic matrix is generally used by several network management tasks in a data center network, such as traffic engineering and anomaly detection. It gives a flow-level view of the network traffic volume. Despite the explicit importance of the traffic matrix, it is significantly difficult to implement a large-scale measurement to build an absolute traffic matrix. Generally, the traffic matrix obtained by the operators is imperfect, i.e., some traffic data may be lost. Hence, we focus on the problems of recovering these missing traffic data in this paper. To recover these missing traffic data, we propose the spatio-temporal Kronecker compressive sensing method, which draws on Kronecker compressive sensing. In our method, we account for the spatial and temporal properties of the traffic matrix to construct a sparsifying basis that can sparsely represent the traffic matrix. Simultaneously, we consider the low-rank property of the traffic matrix and propose a novel recovery model. We finally assess the estimation error of the proposed method by recovering real traffic

Enhancement of pair creation due to locality in bound-continuum interactions

Electron-positron pair production from vacuum is studied in combined background fields, a binding electric potential well and a laser field. The production process is triggered by the interactions between the bound states in the potential well and the continuum states in the Dirac sea. By tuning the binding potential well, the pair production can be strongly affected by the locality of the bound states. The narrower bound states in position space are more efficient for pair production. This is in contrast to what is commonly expected that the wider extended bound states have larger region to interact with external fields and would thus create more particles. This surprise can be explained as the more localized bound states have a much wider extension in the momentum space, which can enhance the bound-continuum interactions in the creation process. This enhancement manifests itself in both perturbative and non-perturbative production regimes

Antiviral treatment alters the frequency of activating and inhibitory receptor-expressing natural killer cells in chronic Hepatitis B virus infected patients

Natural killer (NK) cells play a critical role in innate antiviral immunity, but little is known about the impact of antiviral therapy on the frequency of NK cell subsets. To this aim, we performed this longitudinal study to examine the dynamic changes of the frequency of different subsets of NK cells in CHB patients after initiation of tenofovir or adefovir therapy. We found that NK cell numbers and subset distribution differ between CHB patients and normal subjects; furthermore, the association was found between ALT level and CD158b+ NK cell in HBV patients. In tenofovir group, the frequency of NK cells increased during the treatment accompanied by downregulated expression of NKG2A and KIR2DL3. In adefovir group, NK cell numbers did not differ during the treatment, but also accompanied by downregulated expression of NKG2A and KIR2DL3. Our results demonstrate that treatment with tenofovir leads to viral load reduction, and correlated with NK cell frequencies in peripheral blood of chronic hepatitis B virus infection. In addition, treatments with both tenofovir and adefovir in chronic HBV infected patients induce a decrease of the frequency of inhibitory receptor+ NK cells, which may account for the partial restoration of the function of NK cells in peripheral blood following treatment

Production and Management Simulation of Family Pasture in Different Pastoral Areas Based on OMMLP Model

Family ranch grassland livestock production optimal management model was used to simulate the grassland supply and livestock demand, family economic status under different stocking rates senarion with collection of grassland, livestock, and economics data from Wuzhumuqin Banner and Tongliao as two types of pastoral areas in Inner Mongolia Autonomous Region. The livestock is grazing all year long in Wuzhumuqin Banner, but the livestock is grazing in summer and feeding in hovel in winter in Tongliao, which we call it as semi-farming and semi-pastoral area. The results showed that summer grassland productivity could meet the energy demand of livestock. As the temperature drops in winter and spring, the energy demand of livestock increases, and there is excessive supplementary feeding suff from December to February in the whole pastoral area, and the supplementary feeding amount from January to next January in the semi-agricultural and semi-pastoral areas is not enough to meet the maintenance needs of livestock requirement. The methane emission of herds was more in summer than in winter, and the average methane emission of herds was 3.87 kg/ day and 3.28 kg/ day in the whole grazing area and semi-farming and semi-grazing area, respectively. When the stocking rate of typical households in the whole pastoral area and semi-agricultural and semi-pastoral area was adjusted to 1.34 sheep units/ha and 1.65 sheep units/ha, the corresponding net income was 198,000 RMB and 81,000 RMB, and the net income of pasture was the highest

Enrichment of committed, chondroitin sulfate-expressing human nucleus pulposus cells over progenitors under alginate encapsulation

INTRODUCTION: Accumulating evidence has suggested a heterogeneous NP cell population in adult human IVDs [1, 2], possibly a result of cells being at different differentiation states. The heterogeneous cell populations include the primitive NP cells (also regarded as notochordal NP cells) [1, 2], mature NP cells, and local disc progenitors [1] with various capacities in proteoglycan production other than chondrocytic NP cells. Cross-linked alginate hydrogel provides a favorable three-dimensional microenvironment for promotion of chondrogenic phenotype [3] with enhanced biosynthesis of proteoglycans (PGs) and collagen II. It has been widely used as a bioactive scaffold for engineering of ...postprin

Momentum-Resolved Electronic Structure of the High-TcT_{c} Superconductor Parent Compound BaBiO3_{3}

We investigate the band structure of BaBiO$_{3}$, an insulating parent compound of doped high-$T_{c}$ superconductors, using \emph{in situ} angle-resolved photoemission spectroscopy on thin films. The data compare favorably overall with density functional theory calculations within the local density approximation, demonstrating that electron correlations are weak. The bands exhibit Brillouin zone folding consistent with known BiO$_{6}$ breathing distortions. Though the distortions are often thought to coincide with Bi$^{3+}$/Bi$^{5+}$ charge ordering, core level spectra show that bismuth is monovalent. We further demonstrate that the bands closest to the Fermi level are primarily oxygen derived, while the bismuth $6s$ states mostly contribute to dispersive bands at deeper binding energy. The results support a model of Bi-O charge transfer in which hole pairs are localized on combinations of the O $2p$ orbitals.Comment: minor changes to text and other figures; includes link to online Supplemental Material; accepted to Phys. Rev. Let

Doping dependent evolution of magnetism and superconductivity in Eu1-xKxFe2As2 (x = 0-1) and temperature dependence of lower critical field Hc1

We have synthesized the polycrystalline samples of Eu1-xKxFe2As2 (x = 0-1) and carried out systematic characterization using x-ray diffraction, ac & dc magnetic susceptibility, and electrical resistivity measurements. We have seen a clear signature of the coexistence of superconducting transition (Tc = 5.5 K) with SDW ordering in our under doped sample viz. x = 0.15. The spin density wave transition observed in EuFe2As2 get completely suppressed at x = 0.3 and superconductivity arises below 20 K. Superconducting transition temperature Tc increases with increase in K content and a maximum Tc = 33 K is reached for x = 0.5, beyond which it decreases again. The doping dependent T(x) phase diagram is extracted from the magnetic and electrical transport data. It is found that magnetic ordering of Eu-moments coexists with superconductivity up to x = 0.6. The isothermal magnetization data taken at 2 K for the doped samples suggest 2+ valence states of Eu ions. We also present the temperature dependence of the lower critical field Hc1 of superconducting polycrystalline samples. The value of Hc1(0) obtained for x = 0.3, 0.5, and 0.7 after taking the demagnetization factor into account is 248, 385, and 250 Oe, respectively. The London penetration depth {\lambda}(T) calculated from the lower critical field does not show exponential behaviour at low temperature, as would be expected for a fully gapped clean s-wave superconductor. In contrast, it shows a T2 power-law feature down to T = 0.4 Tc, as observed in Ba1-xKxFe2As2 and BaFe2-xCoxAs2.Comment: 17 pages, 10 figure