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Binaries have received much attention as possible progenitors of Type Ia supernova (SNIa) explosions, but long-term gravitational effects in tight triple or quadruple systems could also play a key role in producing SNIa. Here we report on the properties of a spectroscopic quadruple (SB4) found within a star cluster: the 2+2 hierarchical system HD 74438. Its membership in the open cluster IC 2391 makes it the youngest (43 My) SB4 discovered so far and among the quadruple systems with the shortest outer orbital period. The eccentricity of the 6 y outer period is 0.46 and the two inner orbits, with periods of 20.5 d and 4.4 d, and eccentricities of 0.36 and 0.15, are not coplanar. Using an innovative combination of ground-based high resolution spectroscopy and Gaia/Hipparcos astrometry, we show that this system is undergoing secular interaction that likely pumped the eccentricity of one of the inner orbits higher than expected for the spectral types of its components. We compute the future evolution of HD 74438 and show that this system is an excellent candidate progenitor of sub-Chandrasekhar SNIa through white dwarf (WD) mergers. Taking into account the contribution of this specific type of SNIa better accounts for the chemical evolution of iron-peak elements in the Galaxy than considering only near Chandrasekhar-mass SNIa., accepted for publication in Nature Astronomy

The use of biobanks may accelerate scientists’ chances of developing cures and treatments that are tailored to individuals’ biological makeup-a function of the precision medicine movement. However, given the underrepresentation of certain populations in biobanks, the benefits of these resources may not be equitable for all groups, including older, multi-ethnic populations. The objective of this study was to better understand older, multi-ethnic populations’ 1) perceptions of the value of cancer biobanking research, 2) study design preferences and 3) guidance on ways to promote and increase participation. This study was designed using a community-based participatory research (CBPR) approach and involved eight FGDs with 67 older (65–74 years old) black and white residents from Baltimore City and Prince George’s County, Maryland. FGDs lasted between 90 and 120 minutes, and participants received a $25 Target gift card for their participation. Analysis involved an inductive approach in which we went through a series of open and axial coding techniques to generate themes and subthemes. Multiple themes emerged from the FGDs for the development of future cancer-related biobanking research including: 1) expectations/anticipated benefits, 2) biobanking design preferences and 3) ways to optimize participation. Overall, most participants were willing to provide biospecimens and favored cancer-related biobank. To increase participation of older, diverse participants in biobanking protocols, researchers need to engage older, diverse persons as consultants in order to better understand the value of biobanking research to individuals from the various populations. Scientists should also incorporate suggestions from the community on garnering trust and increasing comfort with study design.

The results obtained from a drying experiment using infrared heating are compared to those obtained from an analytical model based on correlations for the mass transfer coefficients, which are commonly used to obtain evaporation rates for drying applications. It was shown that the mass transfer coefficients calculated by natural convection correlations are approximately ten times lower than those measured under infrared (IR) exposure. In an attempt to explain this discrepancy, which has been also observed in other studies and explained on the basis of thermal radiation effects, optical properties of the solvent are presented and the implications of the IR and near infrared (NIR) spectrum on the thermal radiation effects and ensuing evaporation rates are discussed. The results show that the correlation for mass transfer coefficient has to take into account the IR radiation temperature and the surface emissivity. This study provides important evaporation data on mass flux and mass transfer coefficients, which cannot be predicted using traditional correlations, for the design of IR assisted drying systems.

Migration of water and ions dissolved in water through concrete is of interest in civil engineering. In particular, the behavior of radionuclides dissolved in water is of great interest to the nuclear industry because significant numbers of nuclear structures contain large amounts of concrete, acting as a barrier to radionuclides against entering the environment. Study of the migration of water molecules and ions in concrete hitherto required destructive chemical analysis. In this work, we present a non-destructive probe to investigate the uptake of uranium, iodine and water into mortar in situ using a time-of-flight neutron imaging method that allows selecting different neutron energies, providing elemental sensitivity in the analysis of the absorption process. First results indicate that water molecules are the fastest migrating species while iodine is significantly slower, and uranium was not observed to migrate through the structure within the time frame of the experiment and furthermore blocks the migration of water.

Single-track laser fusion were simulated using a heat-transfer-solidification-only (HTS) model and its extension with fluid dynamics (HTS_FD) model using a parallel open-source code, which included laminar fluid dynamics, flat-free surface of the molten alloy, heat transfer, phase-change, evaporation, and surface tension phenomena. The results illustrate that the fluid dynamics affects the solidification and ensuing microstructure. For the HTS_FD simulations, thermal gradient, G was found to exhibit a maximum at the extremity of the solidified pool (i.e., at the free surface), while for HTS simulations, G exhibited a maximum around the entire edge of the solidified pool. HTS_FD simulations predicted a wider range of cooling rates than the HTS simulations, exhibited an increased spread in the solidification speed, V variation within the melt-pool with respect to the HTS model results. Primary dendrite arm spacing (PDAS) were evaluated based on power law correlations and marginal stability theory models using the (G, V) from HTS and HTS_FD simulations to quantify the effect of the fluid dynamics on the microstructure. At low-laser powers and low-scan speeds, the PDAS obtained with the fluid dynamics model (HTS_FD) was larger by more than 30 pct with respect to the PDAS calculated with the simple HTS model. A new PDAS correlation, i.e., $$ \lambda_{1} \left[ {\mu {\text{m}}} \right] = 832\;G\left[ {\text{K/m}} \right]^{ - 0.5} V\left[ {\text{m/s}} \right]^{ - 0.25} $$ λ 1 μ m = 832 G K/m - 0.5 V m/s - 0.25 , which uses the (G, V) results from the HTS_FD model was developed and validated against experimental results.

Adoption of metal additive manufacturing (AM) components in property-critical applications requires predictable performance of fabricated metal AM parts. In-situ diagnostics coupled with material models provide a pathway for qualification of AM whereby a prime objective is to capture data that inform or validate models or theory. Part of this is to understand the solidification and cooling of the material through diagnostics in order to ensure the part is being built correctly and that microstructures and properties are predictable. We have utilized high-energy X-ray diffraction to provide a unique probe for bulk material characterization in-situ during additive manufacture. The current work is focused on presenting the opportunities and potential pitfalls associated with extracting microstructural information from diffraction data that is necessarily limited due to the dynamic nature of the process. We present diffraction measurements and Rietveld refinement of stainless steel wire-arc line depositions using 71 keV X-rays, providing information on temperature, phase evolution, and residual stress during the deposition of a single-layer of 308L stainless filler wire on a 304L stainless steel substrate. In addition to observing both the liquid/solid and solid-state phase transformations, this methodology can be used to map the extent of the melt pool, identify thermal gradients, and measure residual stresses in materials during deposition.

Wildfires are having both devastating and regenerative impacts on the ecosystems in the Pacific Northwest of North America. Balsamorhiza sagittata and B. deltoidea (balsamroot) are ecologically important species in this region, and B. sagittata populations are increasing, while B. deltoidea is critically imperiled. The aim of this research was to establish in vitro protocols for germination and regeneration of Balsamorhiza spp. to enable conservation efforts. It was hypothesized that karrikins, which are plant growth regulators released from burning plants during wildfires, would induce seed germination in Balsamorhiza spp. Three karrikins (KAR1, KAR2, and KAR11) were tested for the ability to enhance germination in these species at two levels (5 or 10 μM). KAR2 had the strongest positive effect on germination and induced 47% and 60% germination, respectively, in B. sagittata seeds compared to 14% germination obtained in the control (water agar media). In B. deltoidea, KAR2 treatment resulted in a germination rate of 73.1% and 100%, compared to 69% in the control. A germplasm collection of seedlings of both species was established for conservation and regeneration experiments. Thidiazuron treatment (10 μM) induced formation of embryo-like structures in seedlings of both B. sagittata and B. deltoidea, with regenerants originating from the crown of seedlings. The present study provides in vitro methods for conservation and mass propagation of Balsamorhiza species.

Methods for postirradiation characterization of bulk (cm3) irradiated materials or even spent nuclear fuels are sparse due to their extremely radioactive nature. While several methods exist to characterize smaller volumes (

Given two arbitrary closed sets in Euclidean space, to guarantee that the method of alternating projections converges locally at linear rate to a point in the intersection, a simple transversality assumption suffices. Exact projection onto nonconvex sets is typically intractable, but we show that computationally cheap inexact projections may suffice instead. In particular, if one set is defined by sufficiently regular smooth constraints, then projecting onto the approximation obtained by linearizing those constraints around the current iterate suffices. On the other hand, if one set is a smooth manifold represented through local coordinates, then the approximate projection resulting from linearizing the coordinate system around the preceding iterate on the manifold also suffices.

In situ high-energy X-ray diffraction measurements were completed during deposition of 308L stainless steel wire onto a 304L stainless steel substrate. Attempts were made to extract microstructural features such as phase fraction and internal stress, as well as temperature evolution immediately following the deposition. The limited data that could be collected during deposition and rapid solidification are critically examined. High-energy X-rays coupled with relatively slow detectors were utilized to enable determination of orientation-dependent lattice parameters accurately enough to comment on phase strain evolution between austenite and ferrite. Information about the hydrostatic and deviatoric stress states of the constituent phases was determined on time scales that are relevant to their development. However, the time resolution of the technique was insufficient to monitor phase evolution during the solid–solid phase transformation and, more so, during solidification. Moreover, the accurate and absolute determination of inherently statistical parameters, such as phase fraction, depends critically on the ability to sample a statistically significant numbers of grains in the microstructure.

Cheetahs in captivity are frequently afflicted by chronic disease conditions that are rare in their free-ranging counterparts and in other felids. To date, clear pathophysiological mechanisms for some of these diseases have not been established. In order to better understand these conditions in this species, we have adopted a systems biology approach to cheetah metabolism, with the hope of generating new hypotheses for future research. As part of a comprehensive metabolome, we determine the serum (N = 42) and urine (N = 26) amino acid profiles of apparently healthy captive cheetahs, housed at the AfriCat Foundation in Namibia, using GC-MS and LC-MS-MS. A total of 36 serum and 38 urine amino acids were identified and quantified. Glutamine was detected in the serum at the highest mean concentration (1624 μmol/L) followed by alanine (771.9 μmol/L), arginine (669.8 μmol/L), and glycine (478.7 μmol/L). Serum glycine, hydroxyproline, prolylproline, proline, and serine concentrations declined significantly with age. Arginine was excreted at the highest mean concentration (740 μmol/L), followed by glutamine (437.1 μmol/L), alanine (397.1 μmol/L), and serine (331.1 μmol/L). The fractional excretion of cystine was by far the highest at 21.92%, followed by hydroxylysine (6.34%), proline-hydroxyproline (5.49%), and α-aminopimelic acid (4.89%). Both urinary glycine and proline-hydroxyproline concentrations decreased significantly with age. None of the serum or urine amino acid concentrations differed significantly between males and females. This study provides some foundational information on the serum and urine amino acid profiles of healthy captive cheetahs.

The hot-tearing resistance of multicomponent Al-Cu alloys during permanent mold casting was investigated using a constrained permanent mold in which the load and temperature were measured. The nominal Cu composition was varied from 5 to 8 wt pct. Casting experiments were conducted without adding any grain-refining inoculants. The following variables, which were obtained from the measured load data during casting, were considered to assess the hot-tearing resistance of the Al-Cu multicomponent alloys: “V”-like signature in the load rate variation, load at solidus point, and load rate average over the freezing range. In addition, a hot-tearing criterion based on the variation of the fraction of solid in the late stages of solidification was used. It was found that all criteria considered can accurately predict the alloys with the lowest and highest hot-tear resistance, respectively. It was found that the rate of measured load during casting could be used to indicate substantial hot tearing. However, the load rate variation could not be used to detect when small hot tears were present. Among all the criteria considered, the load at the solidus point shows an excellent agreement with experimentally observed hot-tearing resistance for all but one alloy. The poorly resistant hot-tearing alloys exhibited mainly coarse columnar grains while the most hot-tearing resistant alloys exhibited a much more refined grain microstructure. This is the first study in which good hot-tear resistance is demonstrated for multicomponent Al-Cu alloys with nominal Cu content greater than 7 wt pct.

By modulating the levels of sex steroid hormones and sex hormone-binding globulin (SHBG), caffeine could be a factor in the development of several conditions in men, including prostate cancer. The aim of this study was to evaluate if caffeine consumption is associated with concentrations of sex steroid hormones and SHBG in men. 1,410 men aged 20 + years who attended the morning examination session of the Third National Health and Nutrition Examination Survey (1988–1991) were included in the analysis. Coffee and soft drink consumption was assessed using a food frequency questionnaire. Daily caffeine intake was estimated by multiplying caffeine content per cup times the daily frequency of coffee, tea, or soft drink consumption. Serum levels of hormones and SHBG were measured by immunoassay. Associations of frequency of beverage consumption or estimated caffeine intake with hormone levels were examined using multivariable linear regression. Coffee consumption was positively associated with SHBG concentration (p = 0.045) taking lifestyle factors into account, but mutually adjusting for testosterone and estradiol attenuated the association; no association with SHBG was observed for soft drink consumption or caffeine intake. No associations between caffeinated beverage consumption and androgen or estrogen concentrations were observed. Men who drink coffee more frequently may have higher circulating SHBG concentration, but there were no consistent associations for soft drinks or caffeine intake.

The purpose of this review is to provide an overview of recent data on the relationship of testosterone with physical function. The safety of testosterone treatment in older men who do not have hypogonadism has increasingly been questioned. In recent years, multiple studies have been performed to better understand the relationship between testosterone and physical function. Overall, the relationship between testosterone and physical function is unclear. Endogenous and exogenous testosterones are associated with favorable changes in body composition and, to a lesser extent, muscle strength. However, the relationship between testosterone and physical function is less clear in healthy older men. Exogenous testosterone is associated with favorable changes in body composition and strength, but further data are needed to understand if treatment is associated with functional improvements and ultimately decreased disability and morbidity.

Let W(A) denote the field of values (numerical range) of a matrix A. For any polynomial p and matrix A, define the Crouzeix ratio to have numerator $$\max \left\{ |p(\zeta )|:\zeta \in W(A)\right\} $$max|p(ź)|:źźW(A) and denominator $$\Vert p(A)\Vert _2$$źp(A)ź2. Crouzeix's 2004 conjecture postulates that the globally minimal value of the Crouzeix ratio is 1 / 2, over all polynomials p of any degree and matrices A of any order. We derive the subdifferential of this ratio at pairs (p, A) for which the largest singular value of p(A) is simple. In particular, we show that at certain candidate minimizers (p, A), the Crouzeix ratio is (Clarke) regular and satisfies a first-order nonsmooth optimality condition, and hence that its directional derivative is nonnegative there in every direction in polynomial-matrix space. We also show that pairs (p, A) exist at which the Crouzeix ratio is not regular.

Here, plutonium metal is a very unusual element, exhibiting six allotropes at ambient pressure, between room temperature and its melting point, a complicated phase diagram, and a complex electronic structure. Many phases of plutonium metal are unstable with changes in temperature, pressure, chemical additions, or time. This strongly affects structure and properties, and becomes of high importance, particularly when considering effects on structural integrity over long periods of time [1]. This paper presents a time-dependent neutron total scattering study of the local and average structure of naturally aging δ-phase239Pu-Ga alloys, together with preliminary results on neutron tomography characterization.

The increasing use of carbon fiber-reinforced polymer matrix composites (CFPC) and aluminum alloys as lightweight materials in the automotive and aerospace industries demands enhanced surface preparation and control of surface morphology prior to joining. In this study, surfaces of both composite and aluminum were prepared for joining using an Nd:YAG laser in a two-beam interference setup, enabling the (1) structuring of the AL 5182 surface, (2) removal of the resin layer on top of carbon fibers, and (3) structuring of the carbon fibers. CFPC specimens of T700S carbon fiber, Prepreg—T83 epoxy, 5 ply thick, 0°/90° plaques were used. The effects of laser fluence, scanning speed, and number of shots-per-spot were investigated on the removal rate of the resin without an excessive damage of the fibers. Optical micrographs, 3D imaging, and scanning electron microscope imaging were used to study the effect of the laser processing on the surface morphology. It was found that an effective resin ablation and a low density of broken fibers for CFPC specimens was attained using laser fluences of 1–2 J/cm2 and number of 2–4 pulses per spot. A relatively large area of periodic line structures due to energy interference were formed on the aluminum surface at laser fluences of 12 J/cm2 and number of 4–6 pulses per spot.

Hypogonadism, or low testosterone, is a common disorder. There are currently no patient-reported outcome (PRO) instruments designed to comprehensively evaluate the symptoms of hypogonadism and to detect changes in these symptoms in response to treatment.The purpose of this study was to develop a PRO instrument, the Hypogonadism Impact of Symptoms Questionnaire (HIS-Q) and to assess its content validity.A literature review, expert clinician input, and qualitative concept elicitation with 39 male hypogonadism patients (four focus groups: n = 25; individual interviews: n = 14; mean age 52.3 ± 14.3 years) from the USA were used to develop the draft HIS-Q. Subsequent cognitive interviews (n = 29; mean age 51.5 ± 15.4 years) were used to evaluate content validity.Emergent discussion with participants yielded symptoms within the sexual, physical, energy, sleep, cognition, and mood domains. Low libido and tiredness were most commonly reported. The initial version of the HIS-Q includes 53 items that were consistently understood by the participants, who found the instrument to be relevant to their experiences with hypogonadism and comprehensive in the content coverage of symptoms.The HIS-Q is a comprehensive PRO measure of hypogonadism symptom severity in males. Its design elements, including the response options and recall period, were suitable, and content validity was confirmed.