High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes and may enable the observation of ...phenomena such as dark-matter particle annihilation or decay. The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments, and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays. Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements, although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE) with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a 'smoothly broken power-law' model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements, clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.
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IJS, KISLJ, NUK, SBMB, UL, UM, UPUK
We demonstrate 2D reconstructions of the fast-ion velocity distribution from two-view fast-ion D-alpha (FIDA) measurements at the EAST tokamak. By expressing the distribution in a basis relying on ...the fast-ion slowing-down process in fusion plasmas, the smoothness and velocity-space resolution of reconstructions are improved. We reconstruct distributions of fast ions born from simultaneous co- and counter-current neutral beam injection and detect the expected distinct change in fast-ion birth pitch when comparing discharges utilizing different neutral beam injectors. For purely co-current injection, we find a good agreement between TRANSP-predicted and reconstructed fast-ion densities, pressures and current densities for energies above 20 keV. We furthermore illustrate the improvement of the reconstructed high-energy range (> 40 keV) of the distribution by combining FIDA with neutron emission spectroscopy measurements with the compact single-plate EJ301 scintillator.
Countries with a high incidence of coronavirus 2019 (COVID-19) reported reduced hospitalisations for acute coronary syndromes (ACS) during the pandemic. This study describes the impact of a ...nationwide lockdown on ACS hospitalisations in New Zealand (NZ), a country with a low incidence of COVID-19.
All patients admitted to a NZ Hospital with ACS who underwent coronary angiography in the All NZ ACS Quality Improvement registry during the lockdown (23 March – 26 April 2020) were compared with equivalent weeks in 2015–2019. Ambulance attendances and regional community troponin-I testing were compared for lockdown and non-lockdown (1 July 2019 to 16 February 2020) periods.
Hospitalisation for ACS was lower during the 5-week lockdown (105 vs. 146 per-week, rate ratio 0•72 95% CI 0•61–0•83, p = 0.003). This was explained by fewer admissions for non-ST-segment elevation ACS (NSTE-ACS; p = 0•002) but not ST-segment elevation myocardial infarction (STEMI; p = 0•31). Patient characteristics and in-hospital mortality were similar. For STEMI, door-to-balloon times were similar (70 vs. 72 min, p = 0•52). For NSTE-ACS, there was an increase in percutaneous revascularisation (59% vs. 49%, p<0•001) and reduction in surgical revascularisation (9% vs. 15%, p = 0•005). There were fewer ambulance attendances for cardiac arrests (98 vs. 110 per-week, p = 0•04) but no difference for suspected ACS (408 vs. 420 per-week, p = 0•44). Community troponin testing was lower throughout the lockdown (182 vs. 394 per-week, p<0•001).
Despite the low incidence of COVID-19, there was a nationwide decrease in ACS hospitalisations during the lockdown. These findings have important implications for future pandemic planning.
The ANZACS-QI registry receives funding from the New Zealand Ministry of Health.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
'Obesity paradox' was not consistently observed in Asians with coronary artery disease (CAD).
The study investigated the association between body composition and outcomes in Chinese patients with ...CAD.
Cohort study.
A total of 3280 patients with angiographically validated CAD were consecutively included. Body fat (BF) percentage and lean mass index (LMI) were evaluated using the Clínica Universidad de Navarra-Body Adiposity Estimator. The rate of mortality from any cause was compared across groups classified by the quartiles of LMI.
During a median period of 24 months, 288 (8.8%) participants died. There was a close association between increasing LMI and reducing mortality rate. However, univariate analyses did not find protective effect of BF on survival. After adjusting for age, sex, diabetes, current smoking, systolic blood pressure, creatinine, white blood cell count, haemoglobin and medication, Cox regression analyses showed that the significant relation between higher quartiles (Q) of LMI and survival benefit (Q4, hazard ratio 0.58 (95% confidence interval: 0.36-0.94) vs. Q3, 0.60 (0.39-0.91) vs. Q2, 0.60 (0.41-0.88) vs. Q1, reference) remained.
Low LMI but not BF predicts all-cause mortality in Chinese patients with CAD.
Common bile duct stone (CBDS) is one of the common diseases in the digestive system, for which endoscopic retrograde cholangiopancreatography (ERCP) is a treatment procedure. However, the risk ...factors for CBDS recurrence after ERCP remains unclear. This study aims to compare the risk factors of CBDS recurrence after ERCP, and to set up a nomogram model to predict the long-term risk.
A retrospective analysis of 355 patients was reviewed. Univariate and multivariate analyses were performed to identify the risk factors for recurrence. The R packages were used for the model building. The validation set contained 100 patients.
The patients were divided into three subgroups: treated by cholecystectomy after ERCP (11.76% recurrence rate), treated without surgery after ERCP (19.70%), and with a prior history of cholecystectomy (43.64%). Each of them has different independent risk factors, and high body mass index (BMI) is correlated with an increased risk among all the subgroups. A prior history of cholecystectomy is a candidate factor that increases the risk of CBDS recurrence in patients older than 60 years, with a greater BMI, or receiving ERCP combined with EPBD. We built a nomogram model to predict the risk of long-term CBDS recurrence based on the risk factors including age, BMI, CBD diameter, the number of CBDS, and the gallbladder- or biliary tract-related events.
CBDS recurrence is related to congenital and anatomical factors. Cholecystectomy would not be helpful to prevent CBDS recurrence, and a prior history of cholecystectomy may indicate a high risk of recurrence.
This paper presents the research on the evolution of shear transformation zone (STZ) in a Pd-based bulk metallic glass (BMG) during serrated flow under nanoindentation. A novel method of estimating ...the STZ volume through statistical analysis of the serrated flow behavior was proposed for the first time. Based on the proposed method, the STZ volume of the studied BMG at various peak loads have been systematically investigated. The results indicate that the measured STZ volumes are in good agreement with that documented in literature, and the STZ size exhibits an increasing trend during indentation. Moreover, the correlation between the serrated flow dynamics and the STZ activation has also been evaluated. It is found that the STZ activation can promote the formation of self-organized critical (SOC) state during serrated flow.
•A novel method was proposed to estimate the volume of shear transformation zone (STZ) in bulk metallic glass through statistical analysis of the serration behavior in nanoindentation.•It was found that the STZ size exhibits an increasing trend during nanoindentation.•The STZ activation can promote the formation of self-organized critical (SOC) phenomena during serrated flow.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Metal/insulator/metal structures composed of active Al top electrodes (TEs) and oxygen-deficient Pr0.7Ca0.3MnO3 (PCMO) insulator layers are prepared on platinized silicon substrates. The junction ...resistance exhibits an obvious negative differential resistance region in the first bias sweep and an irreversible increase from 2 to 100 MOmega in repeated +/-4 V sweeps. The pulse duration needed to fully switch the junctions is found to be on the order of milliseconds. When 100-500 mus negative pulses are used, the junctions show an incomplete switch to the low resistance state (LRS) which exhibits fluctuating resistances. The fluctuation in the LRS is suppressed and the high-to-low resistance ratio increases gradually when the negative pulse duration is increased from 100 to 500 mus. For relaxed junctions, pulse switching experiments reveal that the LRS undergoes a dynamically stable process at the beginning and then reaches a lower and metastable resistance value. Resistance retention tests also indicate that the high resistance state is very stable, while the metastable LRS gradually relaxes to higher resistance values. The experimental results are discussed with the formation and dissociation of an interfacial AlOx layer at the interface between Al TEs and PCMO layers.
A
bstract
Using
e
+
e
−
collision data corresponding to a total integrated luminosity of 12.9 fb
−
1
collected with the BESIII detector at the BEPCII collider, the exclusive Born cross sections and ...the effective form factors of the reaction
e
+
e
−
→
Ξ
−
Ξ
¯
+
are measured via the single baryon-tag method at 23 center-of-mass energies between 3.510 and 4.843 GeV. Evidence for the decay
ψ
3770
→
Ξ
−
Ξ
¯
+
is observed with a significance of 4.5
σ
by analyzing the measured cross sections together with earlier BESIII results. For the other charmonium(-like) states
ψ
(4040),
ψ
(4160),
Y
(4230),
Y
(4360),
ψ
(4415), and
Y
(4660), no significant signal of their decay to
Ξ
−
Ξ
¯
+
is found. For these states, upper limits of the products of the branching fraction and the electronic partial width at the 90% confidence level are provided.
To investigate the correlation between dynamic enhanced energy spectral CT parameters and Ki-67 high expression in hepatocellular carcinoma (HCC).
A cross-sectional study. This retrospective ...case-control study analyzed the clinical data of 101 patients with pathologically confirmed HCC in Xiamen Hospital of Traditional Chinese Medicine and Zhongshan Hospital of Xiamen University from December 2017 to March 2023. These 101 patients included 84 males and 17 females, and the age
(
,
) was 59.0(49.0,66.0)years. These patients were divided into two groups according to the immunohistochemical Ki-67 expression levels in tumor tissues: the high expression group (Ki-67%>20%,
=59) and the low expression group (Ki-67%≤20%,
=42).CT values on 70 keV and 140 keV monochromatic energy images (HU
, HU
, HU
, HU
) and water density (D
, D
) were measured in arterial phase and portal vein phase, and the difference of HU
, HU
, D
values between portal vein and arterial phase (ΔHU
, ΔHU
, ΔD
), as well as ratio of HU
, HU
, D
v
To investigate the anti-explosion behavior of high-strength reinforced concrete (RC) beam subjected to blast load, the ANSYS/LS-DYNA finite element analysis software was applied. Based on ...anti-explosion test results, the effects of reinforcement strength grade, reinforcement ratio and stirrup ratio on dynamic response, failure mode, resistance curve and ductility of RC beams under uniform blast load were studied. The anti-explosion performance of RC beam can be effectively improved by increasing the strength grade of the high-strength reinforcement. When the shear capacity is high enough, the ultimate capacity of high-strength RC beam can be significantly enhanced by increasing its reinforcement ratio. Anti-explosion performance may deteriorate due to the change of failure modes when the reinforcement ratio is increased to a certain extent. Increasing stirrup ratio can improve the shear capacity of high-strength RC beam to guarantee the full utilization of the advantage of high flexural capacity. For high-strength RC beam with sufficiently shear capacity, the further increase of stirrup ratio has a slight effect on the anti-explosion ability.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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