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Longitudinal multi-omics analyses link gut microbiome dysbiosis with recurrent urinary tract infections in women
No full textRecurrent urinary tract infections (rUTIs) are a major health burden worldwide, with history of infection being a significant risk factor. While the gut is a known reservoir for uropathogenic bacteria, the role of the microbiota in rUTI remains unclear. We conducted a year-long study of women with (n = 15) and without (n = 16) history of rUTI, from whom we collected urine, blood and monthly faecal samples for metagenomic and transcriptomic interrogation. During the study 24 UTIs were reported, with additional samples collected during and after infection. The gut microbiome of individuals with a history of rUTI was significantly depleted in microbial richness and butyrate-producing bacteria compared with controls, reminiscent of other inflammatory conditions. However, Escherichia coli gut and bladder populations were comparable between cohorts in both relative abundance and phylogroup. Transcriptional analysis of peripheral blood mononuclear cells revealed expression profiles indicative of differential systemic immunity between cohorts. Altogether, these results suggest that rUTI susceptibility is in part mediated through the gut–bladder axis, comprising gut dysbiosis and differential immune response to bacterial bladder colonization, manifesting in symptoms
Ultrafast Inorganic Crystals with Mass Production Capability for Future High-Rate Experiments
No full textFuture HEP experiments present stringent challenges to inorganic scintillators in both fast timing response and radiation tolerance. This paper reports recent progress in developing ultrafast inorganic scintillators with sub-ns decay time for future precision timing detectors and high-rate experiments. Performance of fast and ultrafast crystals with mass production capability are compared to CsI crystals which are used for the Mu2e calorimeter. Examples are LYSO:Ce, BaF₂ and BaF₂:Y, which are considered for Mu2e-II. Crystal radiation hardness against gamma-rays and hadrons is reported. Current status and development effort for the BaF₂:Y crystals are discussed
A scalable elliptic solver with task-based parallelism for the SpECTRE numerical relativity code
No full textElliptic partial differential equations must be solved numerically for many problems in numerical relativity, such as initial data for every simulation of merging black holes and neutron stars. Existing elliptic solvers can take multiple days to solve these problems at high resolution and when matter is involved, because they are either hard to parallelize or require a large amount of computational resources. Here we present a new solver for linear and nonlinear elliptic problems that is designed to scale with resolution and to parallelize on computing clusters. To achieve this we employ a discontinuous Galerkin discretization, an iterative multigrid-Schwarz preconditioned Newton-Krylov algorithm, and a task-based parallelism paradigm. To accelerate convergence of the elliptic solver we have developed novel subdomain-preconditioning techniques. We find that our multigrid-Schwarz preconditioned elliptic solves achieve iteration counts that are independent of resolution, and our task-based parallel programs scale over 200 million degrees of freedom to at least a few thousand cores. Our new code solves a classic initial data problem for binary black holes faster than the spectral code SpEC when distributed to only eight cores, and in a fraction of the time on more cores. It is publicly accessible in the next-generation SpECTRE numerical relativity code. Our results pave the way for highly parallel elliptic solves in numerical relativity and beyond
The variance of closed geodesics in balls and annuli on the modular surface
No full textWe asymptotically estimate the variance for the distribution of closed geodesics in small random balls or annuli on the modular surface Γ\H. A probabilistic model in which closed geodesics are modeled using random geodesic segments is proposed, and we rigorously analyze this model using mixing of the geodesic flow in Γ\H. This leads to a conjecture for the asymptotic behavior of the variance, which unlike in previously explored cases is not equal to the expected value. We prove this conjecture for small balls and annuli, resolving a question left open by Humphries and Radziwiłł
Kinematics and Feedback in H ii Regions in the Dwarf Starburst Galaxy IC 10
No full textWe present a survey of the central region of the nearest starburst galaxy, IC 10, using the W. M. Keck Observatory Keck Cosmic Web Imager (KCWI) at high spectral and spatial resolution. We map the central starburst of IC 10 to sample the kinematic and ionization properties of the individual star-forming regions. Using the low spectral resolution mode of KCWI, we map the oxygen abundance, and with the high spectral resolution mode, we identify 46 individual H II regions. These H II regions have an average radius of 4.0 pc, star formation rate ∼1.3 × 10⁻⁴ M⊙ yr⁻¹, and velocity dispersion ∼16 km s⁻¹. None of the H II regions appear to be virialized (α_(vir) ≫ 1), and on average, they show evidence of ongoing expansion. IC 10's H II regions are offset from the star-forming-region size–luminosity scaling relationships, as well as Larson's Law that relates size and velocity dispersion. We investigate the balance of inward and outward pressure, P_(in) and P_(out), finding P_(out) > P_(in) in 89% of H II regions, indicating feedback-driven expansion even in these low-mass H II regions. We find warm gas pressure (P_(gas)) provides the dominant contribution to the outward pressure (P_(out)). This counteracts the inward pressure, which is dominated by turbulence in the surrounding gas rather than self-gravity. Five H II regions show evidence of outflows that are most likely supported by either stellar winds (two regions) or champagne flows (three regions). These observations provide new insights into the state of the star-forming regions in IC 10 and negative feedback from low-mass clusters
Cloudy and Cloud-free Thermal Phase Curves with PICASO: Applications to WASP-43b
No full textWe present new functionality within PICASO, a state-of-the-art radiative transfer model for exoplanet and brown dwarf atmospheres, by developing a new pipeline that computes phase-resolved thermal emission (thermal phase curves) from three-dimensional (3D) models. Because PICASO is coupled to Virga, an open-source cloud code, we are able to produce cloudy phase curves with different sedimentation efficiencies (f_(sed)) and cloud condensate species. We present the first application of this new algorithm to hot Jupiter WASP-43b. Previous studies of the thermal emission of WASP-43b from Kataria et al. found good agreement between cloud-free models and dayside thermal emission, but an overestimation of the nightside flux, for which clouds have been suggested as a possible explanation. We use the temperature and vertical wind structure from the cloud-free 3D general circulation models of Kataria et al. and post-process it using PICASO, assuming that clouds form and affect the spectra. We compare our models to results from Kataria et al., including Hubble Space Telescope Wide-Field Camera 3 (WFC3) observations of WASP-43b from Stevenson et al. In addition, we compute phase curves for Spitzer at 3.6 and 4.5 μm and compare them to observations from Stevenson et al. We are able to closely recover the cloud-free results, even though PICASO utilizes a coarse spatial grid. We find that cloudy phase curves provide much better agreement with the WFC3 and Spitzer nightside data, while still closely matching the dayside emission. This work provides the community with a convenient, user-friendly tool to interpret phase-resolved observations of exoplanet atmospheres using 3D models
Enhanced stratospheric intrusion at Lulin Mountain, Taiwan inferred from beryllium-7 activity
No full textBeryllium-7 (⁷Be), produced by the interaction of cosmic radiation with atoms and molecules primarily in the upper troposphere and lower stratosphere, provides a useful tracer of cross-tropopause transport and vertical mixing in the troposphere. In the western Pacific subtropical region, the interaction of the subtropical jet stream with monsoon systems potentially enhances the transport. Here, we report one year of ⁷Be measurements at daily resolution during 2010, at Mt. Lulin (2862 m above mean sea level; NOAA code: LLN), along with other gaseous compounds such as O₃ and CO and meteorological information, to assess processes that affect the variability of ⁷Be. The ⁷Be concentrations are of the order 1 mBq/m³ or less. The ⁷Be activity is generally low during summer, largely due to precipitation and unfavorable conditions of atmospheric dynamics (i.e., prevalence of upward motion), but it is occasionally high because of the influence of typhoons. In winter and spring, stratospheric effects observed at the surface were frequent and significant, thereby directly affecting the strength of stratospheric effects on the troposphere, such as the tropospheric oxidation capacity. The effects of the stratospheric intrusions are seen by negative and positive correlations of ⁷Be with relative humidity and concentration of O₃, respectively. The stratospheric effect is further supported by the presence of downwelling transport in this region in the European Centre for Medium-Range Weather Forecasts-Atmospheric Composition Reanalysis Version 4 CO, O₃, and relative humidity data
An estimation for the effective force transfer medium in radial loading of the cylindrical and spherical geometries
No full textThe radial design of the cylindrical and spherical composites, subjected to the loading requires the quantitative understanding of their spatial stress distribution, which non-linearly depend on both geometry and the applied force. We develop a new framework for estimating the effective medium of the force transfer during considerable loads. Analyzing the horizontal stress profile, we have identified concave-to-convex behavior and we show that the bridging inflection point could be a measure for distinguishing the major force carrying region form the rest. Identifying such borderline, we have analytically estimated the effective force transfer medium, which has been validated via the simulation results and the respective curve-fitting into an oval. Finally, we have shown that having the same amount of material, the major force transfer region in 2D (cylinder) is ≈ 1.4 times larger than the 3D (sphere) case on the onset of yielding and yEQ ≈ 0.53R as their equal stress elevation. The quantified force transfer region could help the design process of the radial composites subjected to considerable amount of force, with stronger surrounding, while the inner regions could compensate in strength
Pseudodickthomssenite, Mg(VO₃)₂·8H₂O, a New Mineral from the Pickett Corral Mine, Bull Canyon, Montrose County, Colorado, USA
No full textPseudodickthomssenite (IMA2021-027), Mg(VO₃)₂·8H₂O, is a new mineral discovered at the Pickett Corral mine, Bull Canyon, Montrose County, Colorado, USA. The mineral formed from the oxidation of montroseite-corvusite assemblages in a moist environment and occurs on asphaltite and on montroseite-corvusite-bearing sandstone in association with dickthomssenite, gypsum, huemulite, lasalite, and trebiskyite. Pseudodickthomssenite is known only from a diverging cluster of striated needles up to about 500 μm long and 20 μm in diameter; the mineral is light tan in color, with a white streak and a silky luster. The crystals are brittle but somewhat flexible in thin fibers. There are two excellent cleavages, {011} and {011̅}, and the fracture is splintery. The measured density is 1.97(2) g/cm³. Electron probe microanalysis provided the empirical formula [Mg_(0.99)Ca_(0.01)]_(Σ1.00)(V⁵⁺O₃)₂·8H₂O. Pseudodickthomssenite is triclinic, P1̅, a = 7.3566(6) Å, b = 9.4672(9) Å, c = 9.5529(9) Å, α = 104.205(7)°, β = 100.786(7)°, γ = 100.157(7)°, V = 616.08(10) ų, and Z = 2. The structure of pseudodickthomssenite (R₁ = 0.0307 for 1124 I > 2σI reflections) contains V⁵⁺O₅ polyhedra that link by edge-sharing to form a zig-zag [VO₃] chain. MgO₂(H₂O)₄ octahedra link the [VO₃] chains into a Mg(H₂O)₄[VO₃]₄ sheet and the sheets are linked to one another via a complex network of hydrogen bonding involving Mg(H₂O)₆ octahedra and isolated H2O groups. The structure is very similar to that of dickthomssenite
Scalable and continuous access to pure cyclic polymers enabled by ‘quarantined’ heterogeneous catalysts
No full textCyclic polymers are topologically interesting and envisioned as a lubricant material. However, scalable synthesis of pure cyclic polymers remains elusive. The most straightforward way is to recover a used catalyst after the synthesis of cyclic polymers and reuse it. Unfortunately, this is demanding because of the catalyst’s vulnerability and inseparability from polymers, which reduce the practicality of the process. Here we develop a continuous circular process, where polymerization, polymer separation and catalyst recovery happen in situ, to dispense a pure cyclic polymer after bulk ring-expansion metathesis polymerization of cyclopentene. It is enabled by introducing silica-supported ruthenium catalysts and newly designed glassware. Different depolymerization kinetics of the cyclic polymer from its linear analogue are also discussed. This process minimizes manual labour, maximizes the security of vulnerable catalysts and guarantees the purity of cyclic polymers, thereby showcasing a prototype of a scalable access to cyclic polymers with increased turnovers (≥415,000) of precious catalysts