Theory of non-Fermi liquid and pairing in electron-doped cuprates

We apply the spin-fermion model to study the normal state and pairing instability in electron-doped cuprates near the antiferromagnetic QCP. Peculiar frequency dependencies of the normal state properties are shown to emerge from the self-consistent equations on the fermionic and bosonic self-energies, and are in agreement with experimentally observed ones. We argue that the pairing instability is in the $d_{x^{2}-y^{2}}$ channel, as in hole-doped cuprates, but theoretical $T_{c}$ is much lower than in the hole-doped case. For the same hopping integrals and the interaction strength as in hole-doped materials, we obtain $T_{c}\sim10$K at the end point of the antiferromagnetic phase. We argue that a strong reduction of $T_{c}$ in electron-doped cuprates compared to hole-doped ones is due to critical role of the Fermi surface curvature for electron-doped materials. The $d_{x^{2}-y^{2}}$-pairing gap $\Delta(\mathbf{k},\omega)$ is strongly non-monotonic along the Fermi surface. The position of the gap maxima, however, does not coincide with the hot spots, as the non-monotonic $d_{x^{2}-y^{2}}$ gap persists even at doping when the hot spots merge on the Brillouin zone diagonals.Comment: 16 page

Flux Discharge Cascades in Various Dimensions

We study the dynamics of electric flux discharge by charged particle pair or spherical string or membrane production in various dimensions. When electric flux wraps at least one compact cycle, we find that a single "pair" production event can initiate a cascading decay in real time that "shorts out" the flux and discharges many units of it. This process arises from local dynamics in the compact space, and so is invisible in the dimensionally-reduced truncation. It occurs in theories as simple as the Schwinger model on a circle, and has implications for any theory with compact dimensions and electric flux, including string theories and the string landscape.Comment: 19+8 pages, 3 figures, 3 appendice

Superconductivity and Quantum Criticality in CeCoIn_5

Electrical resistivity measurements on a single crystal of the heavy-fermion superconductor CeCoIn_5 at pressures to 4.2 GPa reveal a strong crossover in transport properties near P^* \approx 1.6 GPa, where T_c is a maximum. The temperature-pressure phase diagram constructed from these data provides a natural connection to cuprate physics, including the possible existence of a pseudogap.Comment: 4 pages, 4 figure

Trace-gas metabolic versatility of the facultative methanotroph Methylocella silvestris

The climate-active gas methane is generated both by biological processes and by thermogenic decomposition of fossil organic material, which forms methane and short-chain alkanes, principally ethane, propane and butane1, 2. In addition to natural sources, environments are exposed to anthropogenic inputs of all these gases from oil and gas extraction and distribution. The gases provide carbon and/or energy for a diverse range of microorganisms that can metabolize them in both anoxic3 and oxic zones. Aerobic methanotrophs, which can assimilate methane, have been considered to be entirely distinct from utilizers of short-chain alkanes, and studies of environments exposed to mixtures of methane and multi-carbon alkanes have assumed that disparate groups of microorganisms are responsible for the metabolism of these gases. Here we describe the mechanism by which a single bacterial strain, Methylocella silvestris, can use methane or propane as a carbon and energy source, documenting a methanotroph that can utilize a short-chain alkane as an alternative to methane. Furthermore, during growth on a mixture of these gases, efficient consumption of both gases occurred at the same time. Two soluble di-iron centre monooxygenase (SDIMO) gene clusters were identified and were found to be differentially expressed during bacterial growth on these gases, although both were required for efficient propane utilization. This report of a methanotroph expressing an additional SDIMO that seems to be uniquely involved in short-chain alkane metabolism suggests that such metabolic flexibility may be important in many environments where methane and short-chain alkanes co-occur

Screening for coping style increases the power of gene expression studies

Background: Individuals of many vertebrate species show different stress coping styles and these have a striking influence on how gene expression shifts in response to a variety of challenges. Principal Findings: This is clearly illustrated by a study in which common carp displaying behavioural predictors of different coping styles (characterised by a proactive, adrenaline-based or a reactive, cortisol-based response) were subjected to inflammatory challenge and specific gene transcripts measured in individual brains. Proactive and reactive fish differed in baseline gene expression and also showed diametrically opposite responses to the challenge for 80% of the genes investigated. Significance: Incorporating coping style as an explanatory variable can account for some the unexplained variation that is common in gene expression studies, can uncover important effects that would otherwise have passed unnoticed and greatly enhances the interpretive value of gene expression data

Outcome following surgery for colorectal cancer: analysis by hospital after adjustment for case-mix and deprivation

Outcome, adjusted for case-mix and deprivation, in 3200 patients undergoing resection for colorectal cancer in 11 hospitals in Central Scotland between 1991 and 1994 was studied. There were significant differences among individual hospitals in the proportion of elderly (P<0.001) and deprived (P<0.0001) patients, the mode (P=0.007) and stage (P<0.0001) at presentation, and the proportion of patients who underwent apparently curative resection (P<0.001). There were no significant differences in postoperative mortality. Cancer-specific survival at 5 years following apparently curative resection varied from 59 to 76%; cancer-specific survival at 2 years following palliative resection varied from 22 to 44%. The corresponding hazard ratios, adjusted for the above prognostic factors, for patients undergoing apparently curative resection varied among hospitals from 0.58 to 1.32; and the ratios for palliative resection varied from 0.73 to 1.26. This study demonstrates that, after adjustment for variations in case-mix and deprivation, significant differences in outcome among hospitals following resection for colorectal cancer persist

The CMB and the measure of the multiverse

In the context of eternal inflation, cosmological predictions depend on the choice of measure to regulate the diverging spacetime volume. The spectrum of inflationary perturbations is no exception, as we demonstrate by comparing the predictions of the fat geodesic and causal patch measures. To highlight the effect of the measure---as opposed to any effects related to a possible landscape of vacua---we take the cosmological model, including the model of inflation, to be fixed. We also condition on the average CMB temperature accompanying the measurement. Both measures predict a 1-point expectation value for the gauge-invariant Newtonian potential, which takes the form of a (scale-dependent) monopole, in addition to a related contribution to the 3-point correlation function, with the detailed form of these quantities differing between the measures. However, for both measures both effects are well within cosmic variance. Our results make clear the theoretical relevance of the measure, and at the same time validate the standard inflationary predictions in the context of eternal inflation.Comment: 28 pages; v2: reference added, some clarification

Socioeconomic inequalities in cancer survival in Scotland 1986–2000

We analysed trends in 5-year survival of the 18 commonest cancers in Scotland diagnosed between 1986 and 2000 and followed up to 2004 in each of five deprivation groups based on patients postcode of residence at diagnosis. We estimated relative survival up to 5 years after diagnosis, adjusting for the different background mortality in each deprivation group by age, sex and calendar period. We estimated trends in overall survival and in the deprivation gap in survival up to 2004. Five-year survival improved for all malignancies except bladder cancer and was associated with a widening in the deprivation gap in survival. For 25 of 30 cancer–sex combinations examined, 5-year survival was lower among more deprived patients diagnosed during 1996–2000, and the deprivation gap in survival had widened since 1986–1990 for 15 of these 25 cancers, similar to the trends seen in England and Wales

Unnatural Origin of Fermion Masses for Technicolor

We explore the scenario in which the breaking of the electroweak symmetry is due to the simultaneous presence and interplay of a dynamical sector and an unnatural elementary Higgs. We introduce a low energy effective Lagrangian and constrain the various couplings via direct search limits and electroweak and flavor precision tests. We find that the model we study is a viable model of dynamical breaking of the electroweak symmetry.Comment: 20 pages, 7 eps figure