The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

Design, construction and operation of the ProtoDUNE-SP Liquid Argon TPC

The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7 × 6 × 7.2 m3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP's successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components

Low exposure long-baseline neutrino oscillation sensitivity of the DUNE experiment

The Deep Underground Neutrino Experiment (DUNE) will produce world-leading neutrino oscillation measurements over the lifetime of the experiment. In this work, we explore DUNE's sensitivity to observe charge-parity violation (CPV) in the neutrino sector, and to resolve the mass ordering, for exposures of up to 100 kiloton-megawatt-years (kt-MW-yr). The analysis includes detailed uncertainties on the flux prediction, the neutrino interaction model, and detector effects. We demonstrate that DUNE will be able to unambiguously resolve the neutrino mass ordering at a 3σ (5σ) level, with a 66 (100) kt-MW-yr far detector exposure, and has the ability to make strong statements at significantly shorter exposures depending on the true value of other oscillation parameters. We also show that DUNE has the potential to make a robust measurement of CPV at a 3σ level with a 100 kt-MW-yr exposure for the maximally CP-violating values \delta_{\rm CP}} = \pm\pi/2. Additionally, the dependence of DUNE's sensitivity on the exposure taken in neutrino-enhanced and antineutrino-enhanced running is discussed. An equal fraction of exposure taken in each beam mode is found to be close to optimal when considered over the entire space of interest

Endolysosomal two‐pore channels regulate autophagy in cardiomyocytes

Key points Two‐pore channels (TPCs) were identified as a novel family of endolysosome‐targeted calcium release channels gated by nicotinic acid adenine dinucleotide phosphate, as also as intracellular Na+ channels able to control endolysosomal fusion, a key process in autophagic flux. Autophagy, an evolutionarily ancient response to cellular stress, has been implicated in the pathogenesis of a wide range of cardiovascular pathologies, including heart failure. We report direct evidence indicating that TPCs are involved in regulating autophagy in cardiomyocytes, and that TPC knockout mice show alterations in the cardiac lysosomal system. TPC downregulation implies a decrease in the viability of cardiomyocytes under starvation conditions. In cardiac tissues from both humans and rats, TPC transcripts and protein levels were higher in females than in males, and correlated negatively with markers of autophagy. We conclude that the endolysosomal channels TPC1 and TPC2 are essential for appropriate basal and induced autophagic flux in cardiomyocytes, and also that they are differentially expressed in male and female hearts. Abstract Autophagy participates in physiological and pathological remodelling of the heart. The endolysosomal two‐pore channels (TPCs), TPC1 and TPC2, have been implicated in the regulation of autophagy. The present study aimed to investigate the role of TPC1 and TPC2 in basal and induced cardiac autophagic activity. In cultured cardiomyocytes, starvation induced a significant increase in TPC1 and TPC2 transcripts and protein levels that paralleled the increase in autophagy identified by increased LC3‐II and decreased p62 levels. Small interfering RNA depletion of TPC2 alone or together with TPC1 increased both LC3II and p62 levels under basal conditions and in response to serum starvation, suggesting that, under conditions of severe energy depletion (serum plus glucose starvation), changes in the autophagic flux (as assessed by use of bafilomycin A1) occurred either when TPC1 or TPC2 were downregulated. The knockdown of TPCs diminished cardiomyocyte viability under starvation and simulated ischaemia. Electron micrographs of hearts from TPC1/2 double knockout mice showed that cardiomyocytes contained large numbers of immature lysosomes with diameters significantly smaller than those of wild‐type mice. In cardiac tissues from humans and rats, TPC1 and TPC2 transcripts and protein levels were higher in females than in males. Furthermore, transcript levels of TPCs correlated negatively with p62 levels in heart tissues. TPC1 and TPC2 are essential for appropriate basal and induced autophagic flux in cardiomyocytes (i.e. there is a negative effect on cell viability under stress conditions in their absence) and they are differentially expressed in male and female human and murine hearts, where they correlate with markers of autophagy. </p

Are recent changes in the terrestrial small mammal communities related to land use change? A test using pellet analyses

© 2015, The Ecological Society of Japan. Human-induced landscape changes are expected to have strong effects on the composition and structure of terrestrial small mammal communities (Orders Rodentia and Soricomorpha). However, testing such expectations is difficult due to low detectability of these animals. We used analyses of barn owl (Tyto alba) pellets sampled in the same roosting places during 1977–1991 and again in 2011–2014 to (a) document small mammal community changes and (b) relate them to changes in land use. Forest and synanthropic small mammals increased by a 7 % between both periods, whereas open-land species decreased by 13 %. Man-made loss (crops and meadows) and expansion (forest and urban) of relevant habitat types were closely related to these changes. Localities with land use changes opposite to the general trend showed also an opposite trend in small mammal community change. Land use heterogeneity increased and dominance decreased between both sampling periods, and this pattern was paralleled by an increasing trend in diversity and a decreasing trend in dominance in small mammal communities. Decreasing trends of some generalist northern species with restricted ranges may have been due to climate change. Diet monitoring of barn owls are thus valuable tools for both documenting and analyzing fine-grained small mammal responses to global change.Peer Reviewe