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Properties of fragmentation from an explosively driven 316L stainless steel spherical shell section fabricated by a laser powder bed additive manufacturing process with minimal surface finishing are investigated. This shell is driven by an insensitive high explosive, resulting in high strain rate deformation (>8 × 103 s−1) and failure of the stainless steel. Photonic Doppler velocimetry measures the expansion rate; dynamic radiography and high-speed imaging capture the fracture behavior of the stainless steel. The fracture response of the additively manufactured stainless steel shell is compared to published experimental results on additively manufactured 316L stainless steel and conventionally manufactured wrought 316L and 304 stainless steel shell fragmentation. Despite preferred crack orientation, suggesting the influence of surface grooves on fracture time, fragment size is identical to that measured in a similar experiment on wrought 304 stainless steel. Further analysis indicates that the 316L additively manufactured stainless steel shell exhibits comparable spall strength and fragmentation toughness to conventionally manufactured stainless steel yet lower failure strain due to surface stress concentrations. [ABSTRACT FROM AUTHOR]

Fast analysis of collective Thomson scattering ion acoustic wave features using a deep convolutional neural network model is presented. The network was trained from spectra to predict the plasma parameters, including ion velocities, population fractions, and ion and electron temperatures. A fully kinetic particle-in-cell simulation was used to model a laboratory astrophysics experiment and simulate a diagnostic image of the ion acoustic wave feature. Network predictions were compared with Bayesian inference of the plasma model parameters for both the simulated and experimentally measured images. Both approaches were fairly accurate predicting the simulated image and the network predictions matched a good portion of the Bayesian results for the experimentally measured image. The Bayesian approach is more robust to noise and motivates future work to train deep learning models with realistic noise. The advantage of the deep learning model is making thousands of predictions in a few hundred milliseconds, compared to a few seconds to minutes per prediction for the optimization and Bayesian approaches presented here. The results demonstrate promising capabilities of deep learning models to analyze Thomson data orders of magnitude faster than conventional methods when using the neural network for standalone analysis. If more rigorous analysis is needed, neural network predictions can be used to quickly initialize other optimization methods and increase chances of success. This is especially useful when the dataset becomes very large or highly dimensional and manually refining initial conditions for the entire dataset are no longer tractable. [ABSTRACT FROM AUTHOR]

Recent experiments of laser-driven ejecta microjets performed at OMEGA 60 reveal tortuous jets whereby the jets appear to deviate from their initial trajectory as they travel in vacuum. To understand these data, we perform two dimensional numerical simulations, considering different target thicknesses, pressures, and models of the drive conditions. In particular, modeling the finite laser spot size appears essential in reproducing qualitatively the non-planar shock observed in the experiment. Simulations capture jet deflection by accounting for a slight misalignment of the laser pointing with respect to the groove axis along with spatial variation of the laser pulse intensity. The principal physical mechanism appears to be that lateral momentum is imparted by release waves arising from the non-planar drive. The induced off-axis velocity is small in comparison to the jet axial velocity but integrates into a pronounced deflection over the course of the experiment. The analysis of jet axial and lateral mass distributions is found to be reproduced reasonably by the simulations. Simulated radiographs are in qualitative agreement with the experiments, though their differences point to potential shortcomings in modeling strictly three-dimensional experiments using two-dimensional hydrodynamic simulations. The simple analysis is able to explain part of the observed discrepancy in simulated vs experimental jet masses. [ABSTRACT FROM AUTHOR]

We demonstrate that large apparent converse flexoelectric properties can be obtained in piezoelectric composites using theoretical approaches. To do so, we first present a numerical homogenization method accounting for all electromechanical terms related to strain and the electric field gradient. We then evaluate the coefficients of the model by numerical simulations on periodic piezoelectric composites. After combining the homogenization approach with topology optimization to enhance the converse properties of the composite, we present numerical results that reveal that the apparent converse flexoelectric coefficients, as well as those associated with the higher order coupling terms involving the electric field gradient, are of the same order as the direct flexoelectric properties of the local constituents. These results suggest that both converse and higher order electromechanical coupling effects may contribute strongly to the flexoelectric response and properties of piezoelectric composites. Finally, we show that it is theoretically possible to obtain optimized designs of composites with apparent converse flexoelectric properties 1–2 orders of magnitude larger than ones obtained with naïve guess designs. [ABSTRACT FROM AUTHOR]

Understanding dynamic fragmentation in shock-loaded metals and predicting properties of the resulting ejecta are of considerable importance for both basic and applied science. The nature of material ejection has been shown to change drastically when the free surface melts on compression or release. In this work, we present hydrodynamic simulations of laser-driven microjetting from micron-scale grooves on a tin surface. We study microjet formation across a range of shock strengths from drives that leave the target solid after release to drives that induce shock melting in the target. The shock-state particle velocity (U p) varies from 0.3 to 3 km/s and the shock breakout pressure is 3–120 GPa. The microjet tip velocity is 1–8 km/s and the free-surface velocity varies from 0.1 to 5 km/s. Two tin equations of state are examined: a "soft" model (LEOS 501) where the target melts for U p > --> 1 km/s and a more detailed multiphase model (SESAME 2161) that melts for U p > --> 1.4 km/s. We use these two models to examine the influence of phase change and the choice of the material model on microjet formation and evolution. We observe in our computational results that jet formation can be classified into three regimes: a low-energy regime where material strength affects jet formation, a moderate-energy regime dominated by the changing phase of tin material, and a high-energy regime where results are insensitive to the material model and jet formation is described by an idealized steady-jet theory. Using an ensemble of 2D simulations, we show that these trends hold across a wide range of drive energies and groove angles. [ABSTRACT FROM AUTHOR]

While topological insulators have been widely studied, they typically appear in configurations and properties that are set once a structure is fabricated. As such, there is significant interest in developing topologically tunable or switchable concepts. In this work, we demonstrate that geometric nonlinearity in the form of an elastic snap-through instability can be exploited to switch the topological properties of a Timoshenko arch beam unit cell. We first demonstrate that the phonon band structure can be tuned using geometric nonlinearity and large displacement to reveal the existence of a topological phase transition point. To make this concept fully stable under the removal of the applied force, we then demonstrate the emergence of a bistable unit cell by varying the parameters of the unit cell. In doing so, we show that the bistability of the arch beam unit cell can be harnessed to design a switch that controls the topological nature of an interface between two different 1D phononic crystals. [ABSTRACT FROM AUTHOR]

Coral reefs in the Central Indo-Pacific region comprise some of the most diverse and yet threatened marine habitats. While reef monitoring has grown throughout the region in recent years, studies of coral reef benthic cover remain limited in spatial and temporal scales. Here, we analysed 24,365 reef surveys performed over 37 years at 1972 sites throughout East Asia by the Global Coral Reef Monitoring Network using Bayesian approaches. Our results show that overall coral cover at surveyed reefs has not declined as suggested in previous studies and compared to reef regions like the Caribbean. Concurrently, macroalgal cover has not increased, with no indications of phase shifts from coral to macroalgal dominance on reefs. Yet, models incorporating socio-economic and environmental variables reveal negative associations of coral cover with coastal urbanisation and sea surface temperature. The diversity of reef assemblages may have mitigated cover declines thus far, but climate change could threaten reef resilience. We recommend prioritisation of regionally coordinated, locally collaborative long-term studies for better contextualisation of monitoring data and analyses, which are essential for achieving reef conservation goals. An overview of coral reefs across East and Southeast Asia spanning >24,000 surveys in almost 2,000 sites finds that coral and macroalgal cover are surprisingly stable through time, though correlated environmental variables reveal hidden impact. [ABSTRACT FROM AUTHOR]

Topological insulators (TIs) have recently received significant attention due to the promise of lossless transport of various types of energy. Despite this interest, one outstanding issue is that the topological bandgap and the frequencies that are topologically permitted are typically fixed once the topological structure has been designed and fabricated. Therefore, an open and unresolved question concerns the ability to actively tune both the bandgap magnitude, as well as the frequencies, for which the energy is topologically protected. In this work, we report a mechanically tunable phononic TI using an acoustic analog of the quantum valley Hall effect. We propose a phononic crystal comprised of a soft, hyperelastic material where the phononic band structure is modulated through large deformation of the structure. In doing so, space-inversion symmetry can be broken, which leads to a phase transition between two topologically-contrasted states and the emergence of topologically-protected interface modes according to bulk-edge correspondence. We further demonstrate the robustness of this topological protection of the edge state along the interface, which demonstrates that mechanical deformation can be used to effectively tailor and tune the topological properties of elastic structures. [ABSTRACT FROM AUTHOR]

We developed a simple small-scale experiment to measure the beta decay spectrum of 3 H. The aim of this research is to investigate the presence of sterile neutrinos in the keV region. Tritium nuclei were embedded in a 1 × 1 × 1 cm 3 LiF crystal from the 6 Li(n, α ) 3 H reaction. The energy of the beta electrons absorbed in the LiF crystal was measured with a magnetic microcalorimeter at 40 mK. We report a new method of sample preparation, experiments, and analysis of 3 H beta measurements. The spectrum of a 10-hour measurement agrees well with the expected spectrum of 3 H beta decay. The analysis results indicate that this method can be used to search for keV-scale sterile neutrinos. [ABSTRACT FROM AUTHOR]

Plastic deformation of samples compressed to Mbar pressures at high strain rates at the National Ignition Facility (NIF) forms the basis of ongoing material strength experiments in conditions relevant to meteor impacts, geophysics, armor development, and inertial confinement fusion. Hard x-ray radiography is the primary means of measuring the evolution of these samples, typically employing a slit-collimated high-Z microdot driven by the NIF laser to generate > 40 keV x rays [E. Gumbrell et al., Rev. Sci. Instrum. 89, 10G118 (2018) and C. M. Huntington et al., Rev. Sci. Instrum. 89, 10G121 (2018)]. Alternatively, a dysprosium "micro-flag" target driven by the Advanced Radiographic Capability laser (∼ 2 kJ, 10 ps) can deliver significantly higher spatiotemporal resolution [M. P. Hill et al., Rev. Sci. Instrum. 92, 033535 (2021)], especially in high-opacity samples. Initial experiments revealed problematic brightness and spectral gradients from this source, but by radiographing a set of diamond-turned, 105 µm-thick Pb test objects and supported by simulations using the 3D Monte Carlo code GEANT4, these geometry-dependent gradients across the field of view are quantified and mitigation strategies are assessed. In addition to significantly enhancing the modulation transfer function compared to the existing system, image stacking from multiple layers of image plate is shown to almost double the signal to noise ratio that will reduce uncertainties in future dynamic strength experiments. [ABSTRACT FROM AUTHOR]

It has recently been demonstrated experimentally that a turbulent plasma created by the collision of two inhomogeneous, asymmetric, weakly magnetized, laser-produced plasma jets can generate strong stochastic magnetic fields via the small-scale turbulent dynamo mechanism, provided the magnetic Reynolds number of the plasma is sufficiently large. In this paper, we compare such a plasma with one arising from two pre-magnetized plasma jets whose creation is identical save for the addition of a strong external magnetic field imposed by a pulsed magnetic field generator. We investigate the differences between the two turbulent systems using a Thomson-scattering diagnostic, x-ray self-emission imaging, and proton radiography. The Thomson-scattering spectra and x-ray images suggest that the external magnetic field has a limited effect on the plasma dynamics in the experiment. Although the external magnetic field induces collimation of the flows in the colliding plasma jets and although the initial strengths of the magnetic fields arising from the interaction between the colliding jets are significantly larger as a result of the external field, the energies and morphologies of the stochastic magnetic fields post-amplification are indistinguishable. We conclude that, for turbulent laser-plasmas with supercritical magnetic Reynolds numbers, the dynamo-amplified magnetic fields are determined by the turbulent dynamics rather than the seed fields or modest changes in the initial flow dynamics of the plasma, a finding consistent with theoretical expectations and simulations of turbulent dynamos. [ABSTRACT FROM AUTHOR]

Three alloys were made to represent waste forms for ZIRLO® cladding and metallic fuel wastes by alloying ZIRLO® and a surrogate metallic fuel waste mixture with various amounts of Inconel 718, 304 stainless steel, trim chromium, and trim copper. The objective was to establish if metallic wastes that contain ZIRLO® can be manufactured into durable waste forms for geological repository. Specimens were metallurgically characterized and subjected to electrochemical tests to assess their corrosion resistance. Tests were conducted in acidic and alkaline electrolytes prepared with and without NaCl to simulate ranges of environmental redox and chemical conditions that could occur within a breached waste package in a disposal facility. The microstructures and potentiodynamic scans of these alloys are presented. Surface analyses after the potentiodynamic scans indicate intermetallics enriched in iron, nickel, and copper corroded at relatively low potentials in Cl− solutions and were less durable than the zirconium-chromium phases. [ABSTRACT FROM AUTHOR]

We present measurements of spatially and temporally resolved electron temperature in high-energy-density plasmas using gated x-ray pinhole imagers. A 2D image of bremsstrahlung x-ray self-emission from laser-driven plasma plumes is detected at the same time through two pinholes covered with different filter materials. By comparing the attenuated signal through each filter, a spatially resolved electron temperature as low as 0.1 keV can be estimated. Measurements of the plasma plume taken from different directions indicate that imaging through extended plasmas has a negligible effect on the temperature estimates. Methods for estimating the expected signal, selecting filters, and incorporating the response of the detector are discussed. [ABSTRACT FROM AUTHOR]

This study investigated the incidence, progression and clinical course of myocardial injury-related snake envenomation in South Korea. In addition, this study evaluated whether antivenom guidelines are appropriate to control envenomation in patients with myocardial injury. The study included 198 patients who received antivenom after a snakebite, and they were divided into two groups according to evidence of myocardial injury (defined as elevated troponin I or ischemic change on electrocardiogram) at presentation. Data including serial troponin I, echocardiogram/coronary angiogram findings, the clinical course, and treatment were collected and analyzed. The incidence of myocardial injury at presentation was 15.2%. The troponin I level was 0.11 (0.07–0.56) ng/ml at presentation and tended to decrease over 24 h. Echocardiograms revealed neither regional wall motion abnormalities nor left ventricular dysfunction in 15 of 17 patients, while two patients showed signs of coronary artery stenosis on echocardiograms and coronary angiograms. However, compared with patients without myocardial injury, patients with myocardial injury had a higher frequency of systemic envenomation complications, including bleeding, respiratory failure, hypotension, acute kidney injury, thrombocytopenia and venom-induced consumption coagulopathy (VICC). The patients with myocardial injury at presentation needed significantly more frequent and larger doses of antivenom than indicated by the initial severity of envenomation. Multivariate analysis showed that myocardial injury was associated with the need for additional antivenom administration after initial administration. Myocardial injury is not uncommon after snake envenomation in Korea. Although myocardial injury itself seems to be benign, the clinical course of patients with myocardial injury is complicated, and myocardial injury is associated with the need for additional antivenom administration. The optimal use of antivenom to control envenomation in patents with myocardial injury after snake envenomation in South Korea should be established. [ABSTRACT FROM AUTHOR]

Radiography of low-contrast features in high-density materials evolving on a nanosecond timescale requires a bright photon source in the tens of keV range with high temporal and spatial resolution. One application for sources in this category is the study of dynamic material strength in samples compressed to Mbar pressures at the National Ignition Facility, high-resolution measurements of plastic deformation under conditions relevant to meteor impacts, geophysics, armor development, and inertial confinement fusion. We present radiographic data and the modulation transfer function (MTF) analysis of a multi-component test object probed at ∼100 keV effective backlighter energy using a 5 μm-thin dysprosium foil driven by the NIF Advanced Radiographic Capability (ARC) short-pulse laser (∼2 kJ, 10 ps). The thin edge of the foil acts as a bright line-projection source of hard x rays, which images the test object at 13.2× magnification into a filtered and shielded image plate detector stack. The system demonstrates a superior contrast of shallow (5 μm amplitude) sinusoidal ripples on gold samples up to 90 μm thick as well as enhanced spatial and temporal resolution using only a small fraction of the laser energy compared to an existing long-pulse-driven backlighter used routinely at the NIF for dynamic strength experiments. [ABSTRACT FROM AUTHOR]

We study continuum x-ray emission from hot plasma at the National Ignition Facility (NIF). We find that the x-ray yield in the multi-keV photon energy range is larger in Ti than in Ag or Au. This apparent paradox is due to Ti K-shell vacancies generated by the extraordinary energy density achieved by the NIF lasers. This is supported by direct observations of large continuum enhancement above the Ti K-series limit due to both free–bound (recombination) emission and strong Lyα (H-like) emission. Detailed calculations agree well with our measurements and support our conclusions. [ABSTRACT FROM AUTHOR]

For wireless power transfer and energy harvesting applications, an advantage of having a broadband rectifier is the coverage of a wide range of narrowband frequencies as well as wideband pulses. Many broadband rectifiers have been recently proposed, but their reported characteristics are mainly evaluated at discrete frequencies. Due to the nonlinear nature of rectifiers, such frequency domain characteristics may not directly correspond to the time-domain, especially when input signals are wideband pulses. In this letter, we report the performance evaluation of a broadband rectifier on wideband pulses with various pulse parameters. Here, we use our recently proposed broadband rectifier as a test device. Using Gaussian-modulated RF pulses with various pulse parameters (i.e., pulsewidth, pulse repetition interval, and power), the rectification performance is verified via simulation and measurement. The results demonstrate sufficient rectification efficiency even for short pulses under appropriate parameters, where a maximum rectification efficiency of 71% is obtained. [ABSTRACT FROM AUTHOR]

Background and purpose: The aim was to investigate whether female reproductive factors are associated with dementia. Methods: In all, 4 696 633 post‐menopausal women without dementia were identified using the Korean National Health Insurance System database. Data on reproductive factors were collected using a self‐administered questionnaire. Dementia was determined using dementia diagnosis codes and anti‐dementia drug prescription. Cox proportional hazards regression was conducted to assess the hazard ratio (HR) for dementia according to reproductive factors. Results: During a median follow‐up of 5.74 years, there were 212 227 new cases of all‐cause dementia (4.5%), 162 901 cases of Alzheimer's disease (3.5%) and 24 029 cases of vascular dementia (0.5%). The HR of dementia was 1.15 [95% confidence interval (CI) 1.03–1.16] for menarcheal age ≥17 years compared with menarcheal age 13–14 years, 0.79 (0.77–0.81) for menopausal age ≥55 years compared with menopausal age <40 years, and 0.81 (0.79–0.82) for fertility duration ≥40 years compared with fertility duration <30 years. Whilst being of parity one (HR 0.89, 95% CI 0.85–0.94) and breastfeeding <6 months (HR 0.92, 95% CI 0.88–0.95) was associated with lower risk of dementia, being of parity two or more (HR 1.04, 95% CI 0.99–1.05) and breastfeeding ≥12 months (HR 1.14, 95% CI 1.01–1.07) was associated with a higher risk of dementia than women without parity or breastfeeding history. Use of hormone replacement therapy and oral contraceptives independently reduced the dementia risk by 15% and 10%, respectively. Conclusions: Female reproductive factors are independent risk factors for dementia incidence, with higher risk associated with shorter lifetime endogenous estrogen exposure. [ABSTRACT FROM AUTHOR]

We demonstrate the capability of the Thomson Scattering (TS) diagnostic to measure locally the microscopic electron and ion currents in counter-streaming plasmas unstable to the Weibel or current-filamentation instability. Synthetic TS spectra are calculated with particle distribution functions obtained from particle-in-cell simulations and used to accurately reproduce the simulated currents. We show that this technique allows accurate local measurements of the magnetic field, thus opening the way for the complete experimental characterization of the growth rate, saturation, and nonlinear dynamics of electromagnetic instabilities in plasmas. We illustrate the application of this diagnostic to experimental TS data, which yields local measurements of the magnetic field in Weibel-unstable plasmas and indicates that the magnetic energy density reaches ∼ 1 % of the kinetic energy density of the flows, in agreement with previous numerical studies. [ABSTRACT FROM AUTHOR]

The Notch1 signaling pathway plays a crucial role in determining cell fate, including cell growth and differentiation. In this study, we demonstrated that the antagonistic action of RTK (receptor tyrosine kinase) signaling pathway on the Notch1 signaling pathway is mediated via Ras-PI3K-Akt1. The PI3K-Akt1 signaling pathway was shown to inhibit Notch1 signaling via phosphorylation of RBP-Jk. We observed not only reduced association between Notch1 and RBP-Jk, but also suppression of the Notch1 transcriptional activity. Our results demonstrated that Akt1 functions as a natural inhibitor of the Notch1 signaling pathway via phosphorylation of RBP-Jk. [ABSTRACT FROM AUTHOR]

Ultrahigh pressure and strain-rate (pressure >10 GPa and strain rate >105 s-1) are now attainable using high-power laser systems. A laser pulse drives a shock through a reservoir material which then unloads onto the target specimen. Laser velocimetry measurements at the back surface of the specimen are used to infer the material response. Material strength experiments have been proposed in which the pressure wave reverberates within the specimen and the cumulative resistance to compression by material strength is measured from the recorded velocimetry signature. In this work, ultrahigh pressure and strain-rate reverberation experiments are performed in tantalum, aluminum, and copper to investigate the yield strength behavior in this extreme regime. The experimental results indicate that the measurement sensitivity to yield strength is dominated by the lateral wave effects or impeded by the occurrence of spall. However, computer hydrodynamic code simulations are used to develop an experimental design based on shaping of the laser drive pulse that circumvents these difficulties. Simulations using the Steinberg–Guinan yield strength model and applying the design indicate the capability of measuring a factor-of-2 strength deviation from that predicted by the model with accuracy equal to or greater than the velocimetry measurement error. [ABSTRACT FROM AUTHOR]

By utilizing a sharp magnetic needle made of a sintered Nd2Fe14B permanent magnet, we were able to produce a strong magnetic field of up to approximately 560 kA/m in a transmission electron microscope and succeeded in observing the magnetization reversal in a thin film of sintered Nd2Fe14B by in situ Lorentz microscopy. The increase in the magnetic field induced by the magnetic needle led to a pair of straight magnetic domain walls forming abruptly from the grain boundary. The successive nucleation in the neighboring grain started at the grain boundary adjacent to the magnetic domain wall formed first. Eventually, the magnetic domain walls in the neighboring grains connected and moved continuously and finally disappeared. [ABSTRACT FROM AUTHOR]

Summary: Background: Actinic keratosis (AK) is a common sun‐induced skin disorder that can progress to invasive squamous cell carcinoma. However, there is still no reliable method to predict high‐risk AK. Aim: To identify markers that reflect the biological behaviour of AK and to understand the pathogenesis of AK. Methods: In total, 52 patients with AK and 17 site‐matched healthy controls (HCs) were enrolled. We evaluated solar elastosis and immunohistochemical features using antibodies to p53, vitamin D receptor (VDR), claudin‐1 and Langerin (CD207). Comparisons between AK and HC skin were performed and analyses carried out according to the pathological grade of AK. Results: We found that in both patients and HCs, solar elastosis increased and Langerhans cell (LC) density decreased with ageing. Solar elastosis and p53 expression were higher and VDR expression was lower in patients than in HCs; however, there was no statistical difference between them in relation to the pathological grade of AK. Claudin‐1 expression gradually decreased from HC skin to severe AK, and particularly decreased in areas with epidermal atypia. LC density in severe AK was significantly lower than in HC skin and mild AK, while there was no difference in LC density between HC skin, mild AK and moderate AK. Conclusions: Claudin‐1 could be a useful marker of the pathological severity of AK. In addition, p53 increases and VDR decreases in AK, not in a gradual manner but in the early steps of carcinogenesis. LC density is relatively maintained in AK until it reaches severe dysplasia. [ABSTRACT FROM AUTHOR]

Background: Surfactant protein D (SPD) is a member of the collectin family that lines the airway epithelial cells with host defense. However, the role of SPD in the pathogenesis of aspirin‐exacerbated respiratory disease (AERD) is still unclear. Methods: The serum SPD level was measured in patients with AERD (n = 336), those with aspirin‐tolerant asthma (ATA, n = 442), and healthy controls (HC, n = 104). Polymorphisms of SFTPD in the study subjects were analyzed. The effect of LTE4 on SPD production through eosinophil infiltration was investigated in BALB/c mice. The protective function of SPD against eosinophils inducing inflammation and remodeling was assessed in vitro/vivo. The potential efficacy of nintedanib against airway remodeling through the production of SPD was evaluated. Results: The serum SPD level was significantly lower (P < .001) in AERD compared with ATA patients, and negatively correlated with fall in FEV1 (%) after lysine‐aspirin bronchoprovocation test and/or the urinary LTE4 level. In addition, polymorphism of SFTPD at rs721917 was significantly different in the study subjects (odds ratio, 1.310; 95% confidence intervals, 2.124‐3.446; P = .002). LTE4‐exposed mice showed an increased eosinophil count with a decreased SPD level in bronchoalveolar lavage fluid. Eosinophils increased α‐smooth muscle actin expression in airway epithelial cells, which was attenuated by SPD treatment. Furthermore, nintedanib protected the airway epithelial cells against eosinophils by enhancing the production of SPD. Conclusion: The decreased level of SPD in AERD was associated with airway inflammation/remodeling under the eosinophilic condition, suggesting that modulation of SPD may provide a potential benefit in AERD. High level of leukotriene E4 induces eosinophil infiltration in the lungs, leading to the reduction of surfactant protein D in patients with AERD. Decreased level of surfactant protein D and increased number of eosinophils enhance airway inflammation/remodeling. Modulation of surfactant protein D may provide a potential benefit in airway epithelium against eosinophils. [ABSTRACT FROM AUTHOR]

Presents a study which compared chlorine-doped active layers with undoped ones and demonstrated strain analysis from x-ray and photoluminescence data. Experimental procedures; Results and discussion; Conclusions.

Summary: The use of calcium phosphate bone cement has been described to allow for retention of reduction. Therefore, we evaluated whether augmentation with resorbable calcium phosphate could improve fracture stability in osteoporotic hip fractures. The results showed that augmentation with calcium phosphate cement significantly improved the stability of intertrochanteric fractures.Introduction: The aim with this study was to measure whether augmentation with resorbable calcium phosphate cement could improve fracture stability in osteoporotic hip fractures.Methods: We retrospectively reviewed 82 patients who underwent closed reduction and internal fixation with proximal femoral nail (PFN) for unstable intertrochanteric fractures between 2014 and 2017. In 42 of 82 patients, patients were treated with a PFN alone (group I). These patients were compared with 40 patients for whom the same device combined with calcium phosphate cement for augmentation was used (group II). Questionnaire surveys or telephone interviews were conducted and patients completed a self-report Harris hip score (HHS) and visual analog scale (VAS) scores. Radiographic outcomes including mean sliding distance of screw, femoral shortening, and varus collapse were compared. Postoperative complications were compared.Results: Clinical outcomes at 6 months after surgery were equivalent in both groups. Screw sliding, femoral shortening, and varus collapse were all significantly reduced in the cemented group at the last follow-up (p < 0.001, p = 0.005, p < 0.001, respectively). A total of 9 (21%) complications occurred in group I. In contrast, 2 (5%) complications were seen in group II (p = 0.029).Conclusions: Augmentation with calcium phosphate cement significantly improved the stability of intertrochanteric fractures fixed with a PFN and reduced overall failure rates. We believe augmentation with resorbable calcium phosphate cement for osteoporotic hip fractures is a reasonable option in selected patients. [ABSTRACT FROM AUTHOR]

The existences of protein are important to supply nutritional requirements and to support optimal growth performance in modern broiler chicken. The present experiment was conducted to evaluate the effect of purified amino acid (PAA) isolated from animal blood on growth performance and immune response. A total of one hundred of 1-day old broiler chicken were used in the experiment, following a completely randomized design of 4 groups of treatment differed in concentrations of PAA supplementation (T1: control, no PAA addition; T2: 0.05%; T3: 0.1%; and T4: 0.5%) with 4 replicates for each group. Levels of various cytokines, such as IgA, IgG, interleukin (IL)-2, IL-6, tumor necrosis factor α, and interferon γ, were analyzed using an ELISA kit. Insulin-like growth factor 1, an important growth hormone, was also examined using an ELISA kit. The present result showed feed efficiency and average daily feed intake of broiler chicken increased significantly along with increasing concentrations of PAA (P<0.05). Plasma biochemical parameters and carcass traits were affected by supplementation of PAA. Insulin growth factor-1 levels were significantly increased along with increasing concentrations (until 0.5%) of PAA (P<0.05). Inflammatory marker levels significantly differed between the control and treatment groups. These results indicate that purified amino acid isolated from animal blood affected the immune response and growth performance of broiler chicken. Furthermore, PAA can be used in feed supplementation for broiler chickens without causing health issues. It suggests that the beneficial impacts of PAA on immune responses, as well as blood characteristics, may improve broiler performance. [ABSTRACT FROM AUTHOR]

Abstract: Effect of freeze/thaw cycles on the performance of polymer electrolyte membrane fuel cell (PEMFC) is investigated. Freeze/thaw cycle is repeated 40 times. The performance is degraded, as the number of freeze/thaw cycles increases. The maximum degradation is about 35% at high current density. The performance degradation is analyzed based on the change of water distribution. X‐ray visualization is conducted 3 times; before, after 10th and 40th freeze/thaw cycle, respectivly. The water saturation in PEMFC is getting reduced, as the number of freeze/thaw cycles increases. Over‐potential analysis is conducted using visualization result by calculating the proton conductivity. The proton conductivity is decreased about 30% at high current density after 40th freeze/thaw cycle. The change of water distribution is analyzed based on the structural change of the GDL. The water volume change upon freeze/thaw cycle leads to cracks in the micro porous layer. It facilitates water removal from the GDL and leads to low water saturation in PEMFC. [ABSTRACT FROM AUTHOR]

In this study, variations in the contact resistance of electroplated Au-Fe alloy layers with Fe content were investigated. The contact resistance of electroplated Au-Fe alloy layers that were subject to thermal aging at 260°C in the atmosphere, tended to increase significantly with an increase in the Fe content. Through an analysis method employing X-ray photoelectron spectroscopy (XPS/ ESCA) and Auger electron spectroscopy (AES), Ni oxides, such as NiO and Ni2O3, on the surface of the thermally aged electroplated Au-Fe alloy layers were observed. It is believed that the Ni oxide existing on the surface diffused from the underlying electroplated Ni layers to the surface through the grain boundaries in the electroplated Au-Fe layers during the thermal aging. As the Fe content in the electroplated Au-Fe layers increased, the grain size decreased. As the grain size decreases, more Ni oxide was detected on the surface. Therefore, with a rise in the Fe content, more Ni diffuses to the surface via grain boundaries, and more Ni oxide is formed on the surface of the electroplated Au-Fe layers, increasing the contact resistance of the electroplated Au-Fe alloy layers. [ABSTRACT FROM AUTHOR]

Summary: The age and growth of conger eel, Conger myriaster, were investigated by measuring transversely sectioned sagittal otoliths samples from 635 individuals. Sample ages ranged from 1 to 13 years in the female data. Parameters of the von Bertalanffy growth function were estimated using nonlinear regression from back‐calculation, mean length of samples at age relationships, and otolith weight‐at‐age relationships. Best‐fitting value of the three methods was the otolith weight‐at‐age relationship (r2 = .87). Parameters of otolith weight‐at‐age were estimated as L∞ = 143.76 cm, K = 0.081, and t0 = −1.285. Maximum oocyte diameter (MOD) ranged from 50 to 430 μm. Reproductive traits of ovaries showed a positive relationship between GSI and MOD (r2 = .8515). It is suggested that oogenesis begins to develop from 4 years of age and at lengths of about 45 cm TL. In conclusion, these data provide reliable fundamental data for the fish stock management of Conger myriaster in South Korea. [ABSTRACT FROM AUTHOR]

The ion velocity structure of a strong collisional shock front in a plasma with multiple ion species is directly probed in laser-driven shock-tube experiments. Thomson scattering of a 263.25 nm probe beam is used to diagnose ion composition, temperature, and flow velocity in strong shocks ( M ∼ 6 ) propagating through low-density ( ρ ∼ 0.1 mg/cc) plasmas composed of mixtures of hydrogen (98%) and neon (2%). Within the preheat region of the shock front, two velocity populations of ions are observed, a characteristic feature of strong plasma shocks. The ionization state of the Ne is observed to change within the shock front, demonstrating an ionization-timescale effect on the shock front structure. The forward-streaming proton feature is shown to be unexpectedly cool compared to predictions from ion Fokker-Planck simulations; the neon ionization gradient is evaluated as a possible cause. [ABSTRACT FROM AUTHOR]

Energy-transport effects can alter the structure that develops as a supernova evolves into a supernova remnant. The Rayleigh--Taylor instability is thought to produce structure at the interface between the stellar ejecta and the circumstellar matter, based on simple models and hydrodynamic simulations. Here we report experimental results from the National Ignition Facility to explore how large energy fluxes, which are present in supernovae, affect this structure. We observed a reduction in Rayleigh--Taylor growth. In analyzing the comparison with supernova SN1993J, a Type II supernova, we found that the energy fluxes produced by heat conduction appear to be larger than the radiative energy fluxes, and large enough to have dramatic consequences. No reported astrophysical simulations have included radiation and heat conduction self-consistently in modeling supernova remnants and these dynamics should be noted in the understanding of young supernova remnants. [ABSTRACT FROM AUTHOR]

Magnetic fields are ubiquitous in the Universe. The energy density of these fields is typically comparable to the energy density of the fluid motions of the plasma in which they are embedded, making magnetic fields essential players in the dynamics of the luminous matter. The standard theoretical model for the origin of these strong magnetic fields is through the amplification of tiny seed fields via turbulent dynamo to the level consistent with current observations. However, experimental demonstration of the turbulent dynamo mechanism has remained elusive, since it requires plasma conditions that are extremely hard to re-create in terrestrial laboratories. Here we demonstrate, using laser-produced colliding plasma flows, that turbulence is indeed capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. These results support the notion that turbulent dynamo is a viable mechanism responsible for the observed present-day magnetization. [ABSTRACT FROM AUTHOR]

We have studied the spin-reorientation transition of Cu/Ni/Cu (001) system by measuring the strain, coercive field, and magnetic anisotropy of epitaxial Cu/Ni/Cu (001) films. We found that the critical thickness (t[SUBc]) of Ni for the coherent growth of Ni on Cu is below 25 Å and does not occur at the peak in the effective magnetic anisotropy constant (K[SUPeff]) versus 1/t curve, where t is the Ni thickness. The 60-Å Ni film, which is highly strained and shows out-of-plane magnetization, has been irradiated by 1-MeV C ions. After irradiation, the magnetization lies in the plane and the strain in the Ni film is almost released. This shows the close relationship between strain and out-of-plane magnetization in this system. [ABSTRACT FROM AUTHOR]

Epitaxial [Co/Cu] grown on Si (001) has been irradiated by 1 MeV C+ with a dose of 1 10/cm. The intrinsic characteristics of epitaxy, such as crystal structure and fourfold magnetic anisotropy, are conserved after ion irradiation. However, the extrinsic magnetic properties are changed such that the coercivity decreases and the squareness of the hysteresis loop is noticeably improved. The intensity of the Cu (200) peak in the x-ray diffraction pattern increases about three times and its half-width decreases after irradiation. It is concluded that the changes of magnetic properties induced by ion irradiation result from the grain growth and the improved crystalline quality. c 2001 American Institute of Physics. [DOI: 10.1063/1.1384483]. [ABSTRACT FROM AUTHOR]