Exotic Black Hole Thermodynamics in Third-Order Lovelock Gravity

The generalization of Birkhoff's theorem to higher dimensions in Lovelock gravity allows for black hole solutions with horizon geometries of non-constant curvature. We investigate thermodynamic aspects of these `exotic' black hole solutions, with a particular emphasis on their phase transitions. We consider an extended phase space where the cosmological constant acts as a thermodynamic pressure, and examine both uncharged and $U(1)$ charged solutions. In $d=7$, black hole solutions are restricted to having constant-curvature horizon base manifolds. Uncharged $d=7$ black holes possess novel triple point phenomena analogous to those recently uncovered in exotic $d=6$ black holes in Gauss-Bonnet gravity, while their charged counterparts generically undergo small-large black hole phase transitions. In $d=8$, we find that both charged and uncharged black holes exhibit triple point behaviour and small-large black hole transitions. We also show that a wide range of `exotic' horizon geometries can be ruled out due to the appearance of naked singularities.Comment: 24 pages, 9 Figure

Physical black holes in cosmological spacetimes

Working in the semi-classical setting, we present an exactly solvable candidate model for astrophysical black holes, which can be embedded in a cosmological background and possess regular apparent horizons that form in finite observational time. We construct near-horizon quantities from the assumption of regularity of the renormalized expectation value of the energy-momentum tensor, and derive explicit coordinate transformations in the near-horizon region. We discuss the appropriate boundary conditions for the embedding of the model into an FRWL background, describe their evaporation in the linear regime, and highlight consequences for the laws of black hole mechanics when back-reaction is present.Comment: 6 pages, 1 figure. Comments welcome

The use of remote monitoring of cardiac implantable devices during the COVID-19 pandemic: an EHRA physician survey

It is unclear to what extent the COVID-19 pandemic has influenced the use of remote monitoring (RM) of cardiac implantable electronic devices (CIEDs). The present physician-based European Heart Rhythm Association (EHRA) survey aimed to assess the influence of the COVID-19 pandemic on RM of CIEDs among EHRA members and how it changed the current practice. The survey comprised 27 questions focusing on RM use before and during the pandemic. Questions focused on the impact of COVID-19 on the frequency of in-office visits, data filtering, reasons for initiating in-person visits, underutilization of RM during COVID-19, and RM reimbursement. A total of 160 participants from 28 countries completed the survey. Compared to the pre-pandemic period, there was a significant increase in the use of RM in patients with pacemakers (PMs) and implantable loop recorders (ILRs) during the COVID-19 pandemic (PM 24.2 vs. 39.9%, P = 0.002; ILRs 61.5 vs. 73.5%, P = 0.028), while there was a trend towards higher utilization of RM for cardiac resynchronization therapy-pacemaker (CRT-P) devices during the pandemic (44.5 vs. 55%, P = 0.063). The use of RM with implantable cardioverter-defibrillators (ICDs) and CRT-defibrillator (CRT-D) did not significantly change during the pandemic (ICD 65.2 vs. 69.6%, P = 0.408; CRT-D 65.2 vs. 68.8%, P = 0.513). The frequency of in-office visits was significantly lower during the pandemic (P < 0.001). Nearly two-thirds of participants (57 out of 87 respondents), established new RM connections for CIEDs implanted before the pandemic with 33.3% (n = 29) delivering RM transmitters to the patient's home address, and the remaining 32.1% (n = 28) activating RM connections during an in-office visit. The results of this survey suggest that the crisis caused by COVID-19 has led to a significant increase in the use of RM of CIEDs

Evidence for distinct polymer chain orientations in KC60 and RbC60

The KC60 and RbC60 polymer phases exhibit contrasting electronic properties while powder diffraction studies have revealed no definite structural difference. We have performed single crystal X-ray diffraction and diffuse scattering studies of these compounds. It is found that KC60 and RbC60 possess different chain orientations about their axes, which are described by distinct space groups Pmnn and I2/m, respectively. Such a structural difference will be of great importance to a complete understanding of the physical properties.Comment: To be published in Phys. Rev. Let

Anomalous NMR Magnetic Shifts in CeCoIn_5

We report ^{115}In and ^{59}Co Nuclear Magnetic Resonance (NMR) measurements in the heavy fermion superconductor CeCoIn_5 above and below T_c. The hyperfine couplings of the In and Co are anisotropic and exhibit dramatic changes below 50K due to changes in the crystal field level populations of the Ce ions. Below T_c the spin susceptibility is suppressed, indicating singlet pairing.Comment: 4 pages, 4 figure

Case report: Synergetic effect of ischaemia and increased vagal tone inducing ventricular fibrillation in a patient with Brugada syndrome

Background Brugada syndrome (BS) is a hereditary channelopathy associated with syncope, malignant ventricular arrhythmia, and sudden cardiac death. Right ventricular ischaemia and BS have similar underlying substrates precipitating ventricular tachycardia or fibrillation (VF). ................................................................................................................................................................................................... Case summary A 72-year-old woman with BS and a stenosis on the proximal right coronary artery received several subsequent implantable cardioverter-defibrillator shocks due to VF during an episode of extreme nausea with vomiting. ................................................................................................................................................................................................... Discussion This case report emphasizes on the synergetic effect of mild ischaemia and increased vagal tone on the substrate responsible for BS to create pathophysiological changes precipitating VF

Absence of Myocardial Thyroid Hormone Inactivating Deiodinase Results in Restrictive Cardiomyopathy in Mice

Cardiac injury induces myocardial expression of the thyroid hormone inactivating type 3 deiodinase (D3), which in turn dampens local thyroid hormone signaling. Here, we show that the D3 gene (Dio3) is a tissue-specific imprinted gene in the heart, and thus, heterozygous D3 knockout (HtzD3KO) mice constitute a model of cardiac D3 inactivation in an otherwise systemically euthyroid animal. HtzD3KO newborns have normal hearts but later develop restrictive cardiomyopathy due to cardiac-specific increase in thyroid hormone signaling, including myocardial fibrosis, impaired myocardial contractility, and diastolic dysfunction. In wild-type littermates, treatment with isoproterenol-induced myocardial D3 activity and an increase in the left ventricular volumes, typical of cardiac remodeling and dilatation. Remarkably, isoproterenol-treated HtzD3KO mice experienced a further decrease in left ventricular volumes with worsening of the diastolic dysfunction and the restrictive cardiomyopathy, resulting in congestive heart failure and increased mortality. These findings reveal crucial roles for Dio3 in heart function and remodeling, which may have pathophysiologic implications for human restrictive cardiomyopathy

Long-read sequencing of diagnosis and post-therapy medulloblastoma reveals complex rearrangement patterns and epigenetic signatures

Cancer genomes harbor a broad spectrum of structural variants (SVs) driving tumorigenesis, a relevant subset of which escape discovery using short-read sequencing. We employed Oxford Nanopore Technologies (ONT) long-read sequencing in a paired diagnostic and post-therapy medulloblastoma to unravel the haplotype-resolved somatic genetic and epigenetic landscape. We assembled complex rearrangements, including a 1.55-Mbp chromothripsis event, and we uncover a complex SV pattern termed templated insertion (TI) thread, characterized by short (mostly <1 kb) insertions showing prevalent self-concatenation into highly amplified structures of up to 50 kbp in size. TI threads occur in 3% of cancers, with a prevalence up to 74% in liposarcoma, and frequent colocalization with chromothripsis. We also perform long-read-based methylome profiling and discover allele-specific methylation (ASM) effects, complex rearrangements exhibiting differential methylation, and differential promoter methylation in cancer-driver genes. Our study shows the advantage of long-read sequencing in the discovery and characterization of complex somatic rearrangements

Dynamical Mean Field Theory for Self-Generated Quantum Glasses

We present a many body approach for non-equilibrium behavior and self-generated glassiness in strongly correlated quantum systems. It combines the dynamical mean field theory of equilibrium systems with the replica theory for classical glasses without quenched disorder. We apply this approach to study a quantized version of the Brazovskii model and find a self-generated quantum glass that remains in a quantum mechanically mixed state as T -> 0. This quantum glass is formed by a large number of competing states spread over an energy region which is determined within our theory.Comment: 10 pages, 4 figure