Quasiparticles as composite objects in the RVB superconductor

We study the nature of the superconducting state, the origin of d-wave pairing, and elementary excitations of a resonating valence bond (RVB) superconductor. We show that the phase string formulation of the t-J model leads to confinement of bare spinon and holon excitations in the superconducting state, though the vacuum is described by the RVB state. Nodal quasiparticles are obtained as composite excitations of spinon and holon excitations. The d-wave pairing symmetry is shown to arise from short range antiferromagnetic correlations

Spin Ordering and Quasiparticles in Spin Triplet Superconducting Liquids

Spin ordering and its effect on low energy quasiparticles in a p-wave superconducting liquid are investigated. We show that there is a new 2D p-wave superconducting liquid where the ground state is rotation invariant. In quantum spin disordered liquids, the low energy quasiparticles are bound states of the bare Bogolubov- De Gennes ({\em BdeG}) quasiparticles and zero energy skyrmions, which are charge neutral bosons at the low energy limit. Further more, spin collective excitations are fractionalized ones carrying a half spin and obeying fermionic statistics. In thermally spin disordered limits, the quasi-particles are bound states of bare {\em BdeG} quasi-particles. The latter situation can be realized in some layered p-wave superconductors where the spin-orbit coupling is weak.Comment: 5 pages, no figures; published versio

Commercial Potential of Microbial Inoculants for Sheath Blight Management and Yield Enhancement of Rice

Sheath blight of rice is an economically significant disease worldwide. Use of plant growth-promoting rhizobacteria (PGPR), one type of microbial inoculants, for sheath blight management and yield enhancement of rice is gaining popularity in modern agriculture due to increasing concerns with the use of chemical fungicides. Among different microbial inoculants, PGPR are used for their growth-promoting activities and managing sheath blight in rice. However, the efficacy of experimental PGPR strains is typically not consistent under field conditions due to limited knowledge of their formulations, shelf life, delivery systems, compatibility with chemicals and agronomic practices, and the mode of action. In this chapter, a general review on scope and commercial potential of various PGPR for rice sheath blight management and yield enhancement is provided. Efficacy results obtained from tests with Integral®, a current commercial product, which contains the strain Bacillus subtilis MBI600, are presented as an example of the potential for PGPR in management strategies for sheath blight

Weak Phase γ\gamma and Strong Phase δ\delta from CP Averaged B→ππB\to \pi\pi and πK\pi K Decays

Assuming SU(3) symmetry for the strong phases in the four decay modes B\rarrow \pi^-\pi^+, \pi^0 \pi^+, \pi^- K^+, \pi^- \bar{K}^0 and ignoring the relative small electroweak penguin effects in those decays, the weak phase $\gamma$ and the strong phase $\delta$ can be determined in a model independent way by the CP-averaged branching ratios of the four decay modes. It appears that the current experimental data for $B\to \pi\pi$ and $\pi K$ decays prefer a negative value of $\cos\gamma\cos\delta$. By combining with the other constraints from $V_{ub}$, $B^{0}_{d,s}-\bar{B}^{0}_{d,s}$ mixings and indirect CP-violating parameter $\epsilon_K$ within the standard model, two favorable solutions for the phases $\gamma$ and $\delta$ are found to lie in the region: 35^{\circ}\alt\gamma\alt 62^{\circ} and 106^{\circ}\alt \delta \alt 180^{\circ} or 86^{\circ}\alt\gamma\alt 151^{\circ} and 0^{\circ}\alt\delta\alt 75^{\circ} within 1$\sigma$ standard deviation. It is noted that if allowing the standard deviation of the data to be more than 1$\sigma$, the two solutions could approach to one solution with a much larger region for the phases $\gamma$ and $\delta$. Direct CP asymme try $a_{\epsilon''}^{(\pi^- K^+)}$ in B\rarrow \pi^-K^+ decay can be as large as the present experimental upper bound. Direct CP asymmetry $a_{\epsilon''}^{(\pi^+\pi^-)}$ in B\rarrow \pi^-\pi^+ decay can reach up to about 40% at 1$\sigma$ level.Comment: 14 Pages, ReVTeX, 5 figures, one figure (Fig.3) is correcte

Charm multiplicity and the branching ratios of inclusive charmless b quark decays in the general two-Higgs-doublet models

In the framework of general two-Higgs-doublet models, we calculate the branching ratios of various inclusive charmless b decays by using the low energy effective Hamiltonian including next-to-leading order QCD corrections, and examine the current status and the new physics effects on the determination of the charm multiplicity $n_c$ and semileptonic branching ratio $B_{SL}$. Within the considered parameter space, the enhancement to the ratio $BR(b \to s g)$ due to the charged-Higgs penguins can be as large as a factor of 8 (3) in the model III (II), while the ratio $BR(b \to no charm)$ can be increased from the standard model prediction of 2.49% to 4.91% (2.99%) in the model III (II). Consequently, the value of $B_{SL}$ and $n_c$ can be decreased simultaneously in the model III. The central value of $B_{SL}$ will be lowered slightly by about 0.003, but the ratio $n_c$ can be reduced significantly from the theoretical prediction of $n_c= 1.28 \pm 0.05$ in the SM to $n_c= 1.23 \pm 0.05$, $1.18 \pm 0.05$ for $m_{H^+}=200, 100$ GeV, respectively. We find that the predicted $n_c$ and the measured $n_c$ now agree within roughly one standard deviation after taking into account the effects of gluonic charged Higgs penguins in the model III with a relatively light charged Higgs boson.Comment: 25 pages, Latex file, axodraw.sty, 6 figures. Final version to be published in Phys.Rev.

Single-Particle and Collective Motion for Proton-Rich Nuclei on the Astrophysical rp-Process Path

Based on available experimental data, a new set of Nilsson parameters is proposed for proton-rich nuclei with proton or neutron numbers $28\leq N\leq 40$. The resulting single-particle spectra are compared with those from relativistic and non-relativistic mean field theories. Collective excitations in some even--even proton-rich nuclei in the upper $pf$ shell are investigated using the Projected Shell Model with the new Nilsson basis. It is found that the regular bands are sharply disturbed by band crossings involving $1g_{9/2}$ neutrons and protons. Physical quantities for exploring the nature of the band disturbance and the role of the $1g_{9/2}$ single-particle are predicted, which may be tested by new experiments with radioactive beams.Comment: 4 pages, 3 figures, accepted by Phys. Rev. C, Rapid Communicatio

Impact analysis of accidents on the traffic flow based on massive floating car data

The wide usage of GPS-equipped devices enables the mass recording of vehicle movement trajectories describing the movement behavior of the traffic participants. An important aspect of the road traffic is the impact of anomalies, like accidents, on traffic flow. Accidents are especially important as they contribute to the the aspects of safety and also influence travel time estimations. In this paper, the impact of accidents is determined based on a massive GPS trajectory and accident dataset. Due to the missing precise date of the accidents in the data set used, first, the date of the accident is estimated based on the speed profile at the accident time. Further, the temporal impact of the accident is estimated using the speed profile of the whole day. The approach is applied in an experiment on a one month subset of the datasets. The results show that more than 72% of the accident dates are identified and the impact on the temporal dimension is approximated. Moreover, it can be seen that accidents during the rush hours and on high frequency road types (e.g. motorways, trunks or primaries) have an increasing effect on the impact duration on the traffic flow

Association of Structural Magnetic Resonance Imaging Measures With Psychosis Onset in Individuals at Clinical High Risk for Developing Psychosis:An ENIGMA Working Group Mega-analysis

IMPORTANCE The ENIGMA clinical high risk (CHR) for psychosis initiative, the largest pooled neuroimaging sample of individuals at CHR to date, aims to discover robust neurobiological markers of psychosis risk.OBJECTIVE To investigate baseline structural neuroimaging differences between individuals at CHR and healthy controls as well as between participants at CHR who later developed a psychotic disorder (CHR-PS+) and those who did not (CHR-PS-).DESIGN, SETTING, AND PARTICIPANTS In this case-control study, baseline T1-weighted magnetic resonance imaging (MRI) data were pooled from 31 international sites participating in the ENIGMA Clinical High Risk for Psychosis Working Group. CHR status was assessed using the Comprehensive Assessment of At-Risk Mental States or Structured Interview for Prodromal Syndromes. MRI scans were processed using harmonized protocols and analyzed within a mega-analysis and meta-analysis framework from January to October 2020.MAIN OUTCOMES AND MEASURES Measures of regional cortical thickness (CT), surface area, and subcortical volumes were extracted from T1-weighted MRI scans. Independent variables were group (CHR group vs control group) and conversion status (CHR-PS+ group vs CHR-PS- group vs control group).RESULTS Of the 3169 included participants, 1428 (45.1%) were female, and the mean (SD; range) age was 21.1 (4.9; 9.5-39.9) years. This study included 1792 individuals at CHR and 1377 healthy controls. Using longitudinal clinical information, 253 in the CHR-PS+ group, 1234 in the CHR-PS- group, and 305 at CHR without follow-up data were identified. Compared with healthy controls, individuals at CHR exhibited widespread lower CT measures (mean [range] Cohen d = -0.13 [-0.17 to -0.09]), but not surface area or subcortical volume. Lower CT measures in the fusiform, superior temporal, and paracentral regions were associated with psychosis conversion (mean Cohen d = -0.22; 95% CI, -0.35 to 0.10). Among healthy controls, compared with those in the CHR-PS+ group, age showed a stronger negative association with left fusiform CT measures (F = 9.8; P < .001; q < .001) and left paracentral CT measures (F = 5.9; P = .005; q = .02). Effect sizes representing lower CT associated with psychosis conversion resembled patterns of CT differences observed in ENIGMA studies of schizophrenia (rho = 0.35; 95% CI, 0.12 to 0.55; P = .004) and individuals with 22q11.2 microdeletion syndrome and a psychotic disorder diagnosis (rho = 0.43; 95% CI, 0.20 to 0.61; P = .001).CONCLUSIONS AND RELEVANCE This study provides evidence for widespread subtle, lower CT measures in individuals at CHR. The pattern of CT measure differences in those in the CHR-PS+ group was similar to those reported in other large-scale investigations of psychosis. Additionally, a subset of these regions displayed abnormal age associations. Widespread disruptions in CT coupled with abnormal age associations in those at CHR may point to disruptions in postnatal brain developmental processes.Question How are brain morphometric features associated with later psychosis conversion in individuals at clinical high risk (CHR) for developing psychosis?Findings In this case-control study including 3169 participants, lower cortical thickness, but not cortical surface area or subcortical volume, was more pronounced in individuals at CHR in a manner highly consistent with thinner cortex in individuals with established psychosis. Regions that displayed lower cortical thickness in individuals at CHR who later developed a psychotic disorder additionally displayed abnormal associations with age.Meaning In this study, CHR status and later transition to psychosis was robustly associated with lower cortical thickness; abnormal age associations and specificity to cortical thickness may point to aberrant postnatal brain development in individuals at CHR, including pruning and myelination.This case-control study investigates baseline structural magnetic resonance imaging (MRI) differences between individuals at clinical high risk and healthy controls as well as between participants at clinical high risk who later developed a psychotic disorder and those who did not

Search for Decays of B^{0} Mesons into Pairs of Leptons: B{0} -> e^{+}e^{-}, B^{0} -> \mu^{+}\mu^{-} and B^{0} -> e^{\pm}\mu^{\mp}

We search for the decays of the $B^0$ meson into $e^+e^-$, $\mu^+\mu^-$ $e^{\pm}\mu^{\mp}$ pairs in a sample of $9.7\times 10^6$ $B{\bar B}$ pairs recorded by CLEO detector. No signal is found, and the following upper limits on the corresponding branching fractions are established: $<8.3\times 10^{-7}$, $<6.1\times 10^{-7}$, $< 15\times 10^{-7}$ at 90% confidence level. A new lower limit on the Pati-Salam leptoquark mass $M_{LQ}>27$ TeV is established at 90% confidence level.Comment: 10 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN