Fatigue life scattering and prediction of Inconel 718 fabricated by selective laser melting were investigated using miniature specimen tests combined with statistical method and machine learning ...algorithms. The relationship between pore features and fatigue life of the selective laser melting-fabricated specimens was analyzed statistically. The results show that the increase in the size and/or the number of the pores in the specimens, and/or the decrease in the distance from a pore center to the specimen surface degraded the fatigue life. The machine learning and statistical analysis results reveal that the fatigue life are most closely related to the location of the pores compared with the size and the number of pores in the specimens. The finding may provide a potential way to get high-throughput statistical data helping in evaluating defect-dominated scattering and prediction of fatigue life of additive manufactured metallic parts using miniature specimen testing assisted by the machine learning approach.
We examined whether mucosal melanomas are different in their clinical course and patterns of metastases when arising from different anatomic sites. Our hypothesis was that metastatic behavior would ...differ from primary mucosal melanomas at different anatomical sites.
Clinical and pathological data from 706 patients were compared for their stage distribution, patterns of metastases, CKIT/BRAF mutation status, and overall survival for different anatomical sites.
The anatomic sites of the primary mucosal melanomas were from the lower GI tract (26.5%), nasal cavity and paranasal sinuses (23%), gynecological sites (22.5%), oral cavity (15%), urological sites (5%), upper GI tract (5%), and other sites (3.0%). At initial diagnosis, 14.5% were stage I disease, 41% Stage II, 21.5% Stage III, and 23.0% stage IV. Predominant metastatic sites were regional lymph nodes (21.5%), lung (21%), liver (18.5%), and distant nodes (9%). Oral cavity mucosal melanoma had a higher incidence of regional nodal metastases (31.7% versus 19.8%,P = 0.009), and a higher incidence of lung metastases (32.5% versus 18.5%,P = 0.007) compared to other primary mucosal melanomas. There was a 10% incidence of CKIT mutation and 12% BRAF mutation. Mucosal melanomas from nasal pharyngeal and oral, gastrointestinal, gynecological, and urological had a similar survival with a 1-year survival rate (88%, 83%, 86%), 2-year survival rate (66%, 57%, 61%), 5-year survival rate (27%, 16%, 20%), respectively.
The largest sample size allows, for the first time, a comparison of primary melanoma stage and patterns of metastases across anatomical sites. With few exceptions, the presenting stages, incidence of nodal and distant metastases, the site of predilection of distant metastases, or overall survival were similar despite different primary anatomic sites. These findings suggest that clinical trials involving mucosal melanomas and the administration of systemic therapy can be applied equally to mucosal melanomas regardless of their primary anatomic site.
From 1310.6 x 10(6) J/psi and 448.1 x 10(6) psi (3686) events collected with the BESIII experiment, we report the first observation of Sigma(+) and (Sigma) over bar (-) spin polarization in e(+)e(-) ...-> J/psipsi(3686) -> Sigma(+)(Sigma) over bar (-) decays. The relative phases of the form factors Delta Phi have been measured to be (-15.5 +/- 0.7 +/- 0.5)degrees and (21.7 +/- 4.0 +/- 0.8)degrees with J/psi and psi(3686) data, respectively. The nonzero value of Delta Phi allows for a direct and simultaneous measurement of the decay asymmetry parameters of Sigma(+)-> p pi(0) (alpha(0) = -0.998 +/- 0.037 +/- 0.009) and (Sigma) over bar (-)-> (p) over bar pi(0) ((alpha) over bar (0) = 0.990 +/- 0.037 +/- 0.011), the latter value being determined for the first time. The average decay asymmetry, (alpha(0 )- (alpha) over bar (0))/2, is calculated to be -0.994 +/- 0.004 +/- 0.002. The CP asymmetry A(CP,Sigma) = (alpha(0) + (alpha) over bar (0))/(alpha(0) - (alpha) over bar (0)) = -0.004 +/- 0.037 +/- 0.010 is extracted for the first time, and is found to be consistent with CP conservation.
Abstract
A double-peak X-ray burst from the Galactic magnetar SGR J1935+2154 was discovered to be associated with the two radio pulses of FRB 200428 separated by 28.97 ± 0.02 ms. Precise measurements ...of the timing and spectral properties of the X-ray bursts are helpful for understanding the physical origin of fast radio bursts. In this paper, we have reconstructed some information about the hard X-ray events, which were lost because the High Energy X-ray Telescope (HE) on board the Insight-HXMT mission was saturated by this extremely bright burst, and used the information to improve the temporal and spectral analyses of the X-ray burst. The arrival times of the two X-ray peaks by fitting the new Insight-HXMT/HE lightcurve with multi-Gaussian profiles are 2.77 ± 0.45 ms and 34.30 ± 0.56 ms after the first peak of FRB 200428, respectively, while these two parameters are 2.57 ± 0.52 ms and 32.5 ± 1.4 ms if the fitting profile is a fast-rise and exponential decay function. The spectrum of the two X-ray peaks could be described by a cutoff power law with cutoff energy ∼60 keV and photon index ∼1.4; the latter is softer than the result obtained in Li et al. when the two X-ray peaks appeared.
Creating oxide interfaces with precise chemical specificity at the atomic layer level is desired for the engineering of quantum phases and electronic applications, but highly challenging, owing ...partially to the lack of in situ tools to monitor the chemical composition and completeness of the surface layer during growth. Here we report the in situ observation of atomic layer-by-layer inner potential variations by analysing the Kikuchi lines during epitaxial growth of strontium titanate, providing a powerful real-time technique to monitor and control the chemical composition during growth. A model combining the effects of mean inner potential and step edge density (roughness) reveals the underlying mechanism of the complex and previously not well-understood reflection high-energy electron diffraction oscillations observed in the shuttered growth of oxide films. General rules are proposed to guide the synthesis of atomically and chemically sharp oxide interfaces, opening up vast opportunities for the exploration of intriguing quantum phenomena at oxide interfaces.
Using a data sample corresponding to an integrated luminosity of 2.93 fb−1 taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we perform an ...analysis of the semileptonic decays D0(+)→π−(0)μ+νμ. The branching fractions of D0→π−μ+νμ and D+→π0μ+νμ are measured to be (0.272±0.008stat±0.006syst)% and (0.350±0.011stat±0.010syst)%, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of D0(+)→π−(0)e+νe, we calculate the branching fraction ratios to be R0≡BD0→π−μ+νμ/BD0→π−e+νe=0.922±0.030stat±0.022syst and R+≡BD+→π0μ+νμ/BD+→π0e+νe=0.964±0.037stat±0.026syst, which are compatible with the theoretical expectation of lepton flavor universality within 1.7σ and 0.5σ, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.
Visceral fat is a risk factor for non‐alcoholic fatty liver disease (NAFLD). A reduction in sex hormones is associated with increased abdominal fat. Thus, we investigated whether reduced testosterone ...(T) or oestradiol (E2) levels in men are associated with NAFLD and central obesity. The study involved a survey of 1,882 men between 20 and 60 years of age. We detected hepatic fat infiltration by ultrasound. Early morning serum was analyzed for total testosterone (TT), E2, sex hormone‐binding globulin (SHBG), follicle‐stimulating hormone (FSH) and luteinizing hormone (LH). Free testosterone (FT) was calculated using the Vermeulen method. In the studied population, the prevalence of NAFLD, FSH, LH and SHBG increased with age, TT and FT declined with age, and E2 remained stable. However, in the NAFLD group, TT remained stable, FT and E2 declined, and hepatic fat infiltration increased (P < 0.001 for both). Using multivariate analysis, a correlation was found between E2 and NAFLD, with an odds ratio of 0.954 (95% confidence interval: 0.946–0.967). E2 is one of the protective factors against NAFLD in healthy men. T has no significant correlation with NAFLD. Further investigation would be required to assess the clinical consequences of reduced E2 in men with NAFLD, particularly for men whose TT remained stable.
The process e+e− → ϕη is studied at 22 center-of-mass energy points (√s) between 2.00 and 3.08 GeV using 715 pb−1 of data collected with the BESIII detector. The measured Born cross section of e+e− → ...ϕη is found to be consistent with BABAR measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9 σ with mass (2163.5 ± 6.2 ± 3.0) MeV/c2 and width (31.1+21.1−11.6 ± 1.1) MeV, where the first uncertainties are statistical and the second are systematic.
Abstract
We report the timing and spectral analyses of the type-II X-ray bursts from the rapid burster (MXB 1730–335) observed by the Hard X-ray Modulation Telescope (Insight-HXMT) and Swift/X-Ray ...Telescope (XRT). By stacking the long-duration bursts, we find for the first time that the hard X-rays are lagging behind the soft X-rays by 3 s. However, such a lag is not visible for the short-duration bursts, probably because of the poor statistics. For all bursts the energy spectrum is found to be nonthermal, thanks to the broadband coverage of Insight-HXMT. These findings provide new insights into the type-II bursts and require a temporally visible corona for possible interpretation.
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