Mott Transition and Magnetism in Rare Earth Nickelates and its Fingerprint on the X-ray Scattering

The metal-insulator transition (MIT) remains among the most thoroughly studied phenomena in solid state physics, but the complexity of the phenomena, which usually involves cooperation of many degrees of freedom including orbitals, fluctuating local moments, magnetism, and the crystal structure, have resisted predictive ab-initio treatment. Here we develop ab-initio theoretical method for correlated electron materials, based on Dynamical Mean Field Theory, which can predict the change of the crystal structure across the MIT at finite temperature. This allows us to study the coupling between electronic, magnetic and orbital degrees of freedom with the crystal structure across the MIT in rare-earth nickelates. We predict the free energy profile of the competing states, and the theoretical magnetic ground state configuration, which is in agreement with neutron scattering data, but is different from the magnetic models proposed before. The resonant elastic X-ray response at the K-edge, which was argued to be a direct probe of the charge order, is theoretically modelled within the Dynamical Mean Field Theory, including the core-hole interaction. We show that the line-shape of the measured resonant elastic X-ray response can be explained with the "site-selective" Mott scenario without real charge order on Ni sites.Comment: Acknowledgments updated, citations adde

Matter parity as the origin of scalar Dark Matter

We extend the concept of matter parity $P_M=(-1)^{3(B-L)}$ to non-supersymmetric theories and argue that $P_M$ is the natural explanation to the existence of Dark Matter of the Universe. We show that the non-supersymmetric Dark Matter must be contained in scalar 16 representation(s) of $SO(10),$ thus the unique low energy Dark Matter candidates are $P_M$-odd complex scalar singlet(s) $S$ and inert scalar doublet(s) $H_2.$ We have calculated the thermal relic Dark Matter abundance of the model and shown that its minimal form may be testable at LHC via the SM Higgs boson decays $H_1\to DM DM.$ The PAMELA anomaly can be explained with the decays $DM\to \nu l W$ induced via seesaw-like operator which is additionally suppressed by Planck scale. Because the SM fermions are odd under matter parity too, the DM sector is just our scalar relative.Comment: The origin of scalar DM is emphasized, version accepted by PR

Many-Body Electronic Structure of Americium metal

We report computer based simulations of energetics, spectroscopy and electron-phonon interaction of americium using a novel spectral density functional method. This approach gives rise to a new concept of a many-body electronic structure and reveals the unexpected mixed valence regime of Am 5f6 electrons which under pressure acquire the 5f7 valence state. This explains unique properties of Am and addresses the fundamental issue of how the localization delocalization edge is approached from the localized side in a closed shell system.Comment: 4 pages, 3 figure

Dark Matter as the signal of Grand Unification

We argue that the existence of Dark Matter (DM) is a possible consequence of GUT symmetry breaking. In GUTs like SO(10), discrete Z_2 matter parity (-1)^{3(B-L)} survives despite of broken B-L, and group theory uniquely determines that the only possible Z_2-odd matter multiplets belong to representation 16. We construct the minimal non-SUSY SO(10) model containing one scalar 16 for DM and study its predictions below M_{G}. We find that EWSB occurs radiatively due to DM couplings to the SM Higgs boson. For thermal relic DM the mass range M_{DM}\sim (0.1-1) TeV is predicted by model perturbativity up to M_{G}. For M_{DM}\sim (1) TeV to explain the observed cosmic ray anomalies with DM decays, there exists a lower bound on the spin-independent direct detection cross section within the reach of planned experiments.Comment: DM direct detection cross section is corrected by adding s-quark contribution which turned out to be the dominant one. The prediction is just below the present CDMS and XENON10 bound. Extended version, RGE-s included, new references adde

Effects of Increased Flight on the Energetics and Life History of the Butterfly Speyeria mormonia

Movement uses resources that may otherwise be allocated to somatic maintenance or reproduction. How does increased energy expenditure affect resource allocation? Using the butterfly Speyeria mormonia, we tested whether experimentally increased flight affects fecundity, lifespan or flight capacity. We measured body mass (storage), resting metabolic rate and lifespan (repair and maintenance), flight metabolic rate (flight capacity), egg number and composition (reproduction), and food intake across the adult lifespan. The flight treatment did not affect body mass or lifespan. Food intake increased sufficiently to offset the increased energy expenditure. Total egg number did not change, but flown females had higher early-life fecundity and higher egg dry mass than control females. Egg dry mass decreased with age in both treatments. Egg protein, triglyceride or glycogen content did not change with flight or age, but some components tracked egg dry mass. Flight elevated resting metabolic rate, indicating increased maintenance costs. Flight metabolism decreased with age, with a steeper slope for flown females. This may reflect accelerated metabolic senescence from detrimental effects of flight. These effects of a drawdown of nutrients via flight contrast with studies restricting adult nutrient input. There, fecundity was reduced, but flight capacity and lifespan were unchanged. The current study showed that when food resources were abundant, wing-monomorphic butterflies living in a continuous meadow landscape resisted flight-induced stress, exhibiting no evidence of a flight-fecundity or flight-longevity trade-off. Instead, flight changed the dynamics of energy use and reproduction as butterflies adopted a faster lifestyle in early life. High investment in early reproduction may have positive fitness effects in the wild, as long as food is available. Our results help to predict the effect of stressful conditions on the life history of insects living in a changing world.Peer reviewe

Short- and long-term outcomes after heart transplantation in cardiac sarcoidosis and giant-cell myocarditis : a systematic review and meta-analysis

Heart transplantation (HTx) is a valid therapeutic option for end-stage heart failure secondary to cardiac sarcoidosis (CS) or giant-cell myocarditis (GCM). However, post-HTx outcomes in patients with inflammatory cardiomyopathy (ICM) have been poorly investigated. We searched PubMed, Scopus, Science Citation Index, EMBASE, and Google Scholar, screened the gray literature, and contacted experts in the field. We included studies comparing post-HTx survival, acute cellular rejection, and disease recurrence in patients with and without ICM. Data were synthesized by a random-effects meta-analysis. We screened 11,933 articles, of which 14 were considered eligible. In a pooled analysis, post-HTx survival was higher in CS than non-CS patients after 1 year (risk ratio [RR] 0.88, 95% confidence interval [CI] 0.60-1.17; I-2 = 0%) and 5 years (RR 0.72, 95% CI 0.52-0.91; I-2 = 0%), but statistically significant only after 5 years. During the first-year post-HTx, the risk of acute cellular rejection was similar for patients with and without CS, but after 5 years, it was lower in those with CS (RR 0.38, 95% CI 0.03-0.72; I-2 = 0%). No difference in post-HTx survival was observed between patients with and without GCM after 1 year (RR 1.16, 95% CI 0.05-2.28; I-2 = 0%) or 5 years (RR 0.98, 95% CI 0.42-1.54; I-2 = 0%). During post-HTx follow-up, recurrence of CS and GCM occurred in 5% and 8% of patients, respectively. Post-HTx outcomes in patients with CS and GCM are comparable with cardiac recipients with other heart failure etiologies. Patients with ICM should not be disqualified from HTx. [GRAPHICS] .Peer reviewe