Trapped and excited w modes of stars with a phase transition and R>=5M

The trapped $w$-modes of stars with a first order phase transition (a density discontinuity) are computed and the excitation of some of the modes of these stars by a perturbing shell is investigated. Attention is restricted to odd parity (``axial'') $w$-modes. With $R$ the radius of the star, $M$ its mass, $R_{i}$ the radius of the inner core and $M_{i}$ the mass of such core, it is shown that stars with $R/M\geq 5$ can have several trapped $w$-modes, as long as $R_{i}/M_{i}<2.6$. Excitation of the least damped $w$-mode is confirmed for a few models. All of these stars can only exist however, for values of the ratio between the densities of the two phases, greater than $\sim 46$. We also show that stars with a phase transition and a given value of $R/M$ can have far more trapped modes than a homogeneous single density star with the same value of $R/M$, provided both $R/M$ and $R_{i}/M_{i}$ are smaller than 3. If the phase transition is very fast, most of the stars with trapped modes are unstable to radial oscillations. We compute the time of instability, and find it to be comparable to the damping of the $w$-mode excited in most cases where $w$-mode excitation is likely. If on the other hand the phase transition is slow, all the stars are stable to radial oscillations.Comment: To appear in Physical Review

Concomitant Valvular Procedures During LVAD Implantation and Outcomes: An Analysis of the MOMENTUM 3 Trial Portfolio

Purpose: Correction of valvular pathology is often undertaken in patients undergoing LVAD implantation but impact on outcomes is uncertain. We compared clinical outcomes with HeartMate 3 (HM3) LVAD implantation in those with concurrent valve procedures (VP) to those with an isolated LVAD implant within the MOMENTUM3 trial portfolio, including the Pivotal Trial (n=515, NCT02224755) and Continued Access Protocol/ CAP (n=1685, NCT02892955). Methods: The study included 2200 HM3 implanted patients. Among 820 concurrent procedures (including VP, CABG, RVAD, LAA closure), 466 (21.8%) were VPs (HM3+VP), including 81 aortic, 61 mitral, 163 tricuspid, and 85 patients with multiple VPs. Short and Long-term outcomes including peri-operative complications and healthcare resource use, major adverse events and survival were analyzed. Results: Patients undergoing HM3+VP were older (63[54-70] vs. 62[52-68] yrs), with a sicker INTERMACS profile (1-2:41% vs.31%) and higher central venous pressure (11[8-16] vs. 9[6-14] mmHg) compared to HM3 alone (all p\u3c0.05). The cardiopulmonary bypass time (124[97-158] vs.76[59-96] mins); ICU (8.5 [5-16] vs. 7 [5-13]) and hospital length of stay (20 [15-30] vs. 18 [14-24] days) were longer in HM3+VP (all p\u3c0.0001). A significantly higher incidence of stroke (4.9% vs. 2.4%), bleeding (33.9% vs. 23.8%) and right heart failure (41.5% vs. 29.6%) was noted in HM3+VP for 0-30 days post-implant (all p\u3c0.01), but 30-day survival was similar between groups (96.7% vs. 96.1%). There was no difference in 2-year survival in HM3+VP vs HM3 alone patients (HR[95%CI]:0.93 [0.71-1.21];p=0.60). Analysis of individual VPs showed no significant differences in survival compared to HM3 alone (Figure). Conclusion: Concurrent VPs are commonly performed during LVAD implantation, are associated with increased morbidity during the index hospitalization, but short and long-term survival are not impacted adversely when compared with those that undergo an isolated LVAD procedure

Important pharmacogenetic information for drugs prescribed during the SARS-CoV-2 infection (COVID-19)

In December 2019, the severe acute respiratory syndrome virus-2 pandemic began, causing the coronavirus disease 2019. A vast variety of drugs is being used off-label as potential therapies. Many of the repurposed drugs have clinical pharmacogenetic guidelines available with therapeutic recommendations when prescribed as indicated on the drug label. The aim of this review is to provide a comprehensive summary of pharmacogenetic biomarkers available for these drugs, which may help to prescribe them more safelyM.N.-G. is co-financed by the European Social Fund and the Youth European Initiative; grant number PEJ-2018-TL/BMD-1108

Template-stripped gold surfaces with 0.4 nm rms roughness suitable for force measurements. Application to the Casimir force in the 20-100 nm range

Using a template-stripping method, macroscopic gold surfaces with root-mean-square (rms) roughness less than 0.4 nm have been prepared, making them useful for studies of surface interactions in the nanometer range. The utility of such substrates is demonstrated by measurements of the Casimir force at surface separations between 20 and 100 nm, resulting in good agreement with theory. The significance and quantification of this agreement is addressed, as well as some methodological aspects regarding the measurement of the Casimir force with high accuracy.Comment: 7 figure

Majorana solutions to the two-electron problem

A review of the known different methods and results devised to study the two-electron atom problem, appeared in the early years of quantum mechanics, is given, with particular reference to the calculations of the ground state energy of helium. This is supplemented by several, unpublished results obtained around the same years by Ettore Majorana, which results did not convey in his published papers on the argument, and thus remained unknown until now. Particularly interesting, even for current research in atomic and nuclear physics, is a general variant of the variational method, developed by Majorana in order to take directly into account, already in the trial wavefunction, the action of the full Hamiltonian operator of a given quantum system. Moreover, notable calculations specialized to the study of the two-electron problem show the introduction of the remarkable concept of an effective nuclear charge different for the two electrons (thus generalizing previous known results), and an application of the perturbative method, where the atomic number Z was treated effectively as a continuous variable, contributions to the ground state energy of an atom with given Z coming also from any other Z. Instead, contributions relevant mainly for pedagogical reasons count simple broad range estimates of the helium ionization potential, obtained by suitable choices for the wavefunction, as well as a simple alternative to Hylleraas' method, which led Majorana to first order calculations comparable in accuracy with well-known order 11 results derived, in turn, by Hylleraas.Comment: amsart, 20 pages, no figure

Procyanidins are potent inhibitors of LOX-1: a new player in the French Paradox

Lectin-like oxidized LDL receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL (oxLDL) and plays multiple roles in the development of cardiovascular diseases. We screened more than 400 foodstuff extracts for identifying materials that inhibit oxLDL binding to LOX-1. Results showed that 52 extracts inhibited LOX-1 by more than 70% in cell-free assays. Subsequent cell-based assays revealed that a variety of foodstuffs known to be rich in procyanidins such as grape seed extracts and apple polyphenols, potently inhibited oxLDL uptake in Chinese hamster ovary (CHO) cells expressing LOX-1. Indeed, purified procyanidins significantly inhibited oxLDL binding to LOX-1 while other ingredients of apple polyphenols did not. Moreover, chronic administration of oligomeric procyanidins suppressed lipid accumulation in vascular wall in hypertensive rats fed with high fat diet. These results suggest that procyanidins are LOX-1 inhibitors and LOX-1 inhibition might be a possible underlying mechanism of the well-known vascular protective effects of red wine, the French Paradox

The importance of quantum decoherence in brain processes

Based on a calculation of neural decoherence rates, we argue that that the degrees of freedom of the human brain that relate to cognitive processes should be thought of as a classical rather than quantum system, i.e., that there is nothing fundamentally wrong with the current classical approach to neural network simulations. We find that the decoherence timescales ~10^{-13}-10^{-20} seconds are typically much shorter than the relevant dynamical timescales (~0.001-0.1 seconds), both for regular neuron firing and for kink-like polarization excitations in microtubules. This conclusion disagrees with suggestions by Penrose and others that the brain acts as a quantum computer, and that quantum coherence is related to consciousness in a fundamental way.Comment: Minor changes to match accepted PRE version. 15 pages with 5 figs included. Color figures and links at http://www.physics.upenn.edu/~max/brain.html or from [email protected]. Physical Review E, in pres