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Setting inspection intervals based on an accurate prediction of fatigue crack sizes is essential for sustaining the integrity of aeronautical structures. However, the fatigue crack growth and its prognosis are affected by various uncertainties, which makes the current inspection strategy with fixed intervals challenging in managing the aircraft with diverse damage states in a fleet. In this study, an intelligent crack inspection strategy is proposed based on a digital twin, in which a reduced-order fracture mechanics simulation methodology, a validated fatigue crack growth model, and the historical crack length inspection results are integrated into a dynamic Bayesian network. The proposed strategy uses two connected probabilistic processes, which conduct the diagnosis/prognosis and calculate the inspection intervals, respectively, to adaptively set the inspection intervals according to the updating of the digital twin model. The proposed inspection strategy is demonstrated by the various crack growth histories of a helicopter component and benchmarked against several baselines. The results show that the probability of failure can be kept below the threshold, even though the initial crack size and the crack growth parameters are underestimated in the prior distribution. Further applications on more realistic aircraft structures will be carried out in the future.

To compare the combination of intracervical Foley catheter and intravaginal misoprostol administration versus intravaginal misoprostol administration-only for cervical ripening. The Medline, EMBASE, ClinicalTrials.gov, PROSPERO, Scopus, and Cochrane Collaboration databases were searched systematically. Randomized controlled trials that included patients with a singleton viable fetus who underwent induction of labor that required cervical ripening with an unfavorable cervix (Bishop ≤ 6) were eligible for inclusion. Primary outcomes was time to delivery and rate of cesarean delivery. Thirteen trials with 2978 subjects met the inclusion criteria. There was no difference in the incidence of cesarean delivery between the two groups (RR, 0.90; 95 % CI, 0.72-1.14; I

The reduction/precipitation of Cr(vi) could occur simultaneously under alkaline conditions in the presence of thiourea dioxides as reducing agents.

The Altaids, or the Central Asian Orogenic Belts, is generally considered to be the largest Phanerozoic accretionary orogen on Earth, but it is unclear if it was associated with extensive continental crustal growth and whether there is a link between the crustal growth and ore mineralization. This study, based on 5507 whole-rock Nd and 39514 (2443 samples) zircon Hf isotope data of felsic-intermediate-mafic igneous rocks as well as associated 1830 ore deposit data for the Altaids, presents Nd + Hf isotopic contour maps for this region. The maps highlight the three-dimensional (3D) lithospheric compositional architecture of the Altaids and make it possible to quantitatively evaluate the crustal growth and its relationship to ore deposits. The Altaids hosts ~4,107,350 km2 and ~184,830,750 km3 (assuming a crustal thickness of 40-50 km) juvenile crust (εNd(t) > 0), accounting for 58% by isotope-mapped area (~7,010,375 km2) of almost all outcrops of the Altaids (~8,745,000 km2) and formed during 1000–150 Ma (mainly 600–150 Ma). Therefore, the Altaids can be viewed as the largest storage area and most typical "fossils" of the juvenile crust in orogens worldwide. Our results are applicable to other types of orogens, particularly to the final continental collision and its control on mineralization. The juvenile crustal, slightly juvenile-reworked crustal, and slightly reworked crustal provinces controlled the Cu-Au, the Pb-Zn-Ag, and the Li-Be, Nb-Ta, and W-Sn ore deposits. According to the crustal architecture and background of deep compositions, we propose that the ore deposits can be grouped into three types: juvenile crust-related, mixed source (or slightly juvenile crust)-related, and reworked crust-related. This highlights the close relationship between accretion, continental growth, and mineralization and will facilitate exploration for specific ore deposit types in the Altaids.

Despite improvements in microscopically neurosurgical techniques made in recent years, the prognosis of adamantinomatous craniopharyngioma (ACP) is still unsatisfactory. Little is known about cellular atlas and biological features of ACP. Here, we carried out integrative analysis of 44,038 single-cell transcriptome profiles to characterize the landscape of intratumoral heterogeneity and tumor microenvironment (TME) in ACP. Four major neoplastic cell states with distinctive expression signatures were defined, which further revealed the histopathological features and elucidated unknown cellular atlas of ACP. Pseudotime analyses suggested potential evolutionary trajectories between specific neoplastic cell states. Notably, a distinct oligodendrocyte lineage was identified in ACP, which was associated with immunological infiltration and neural damage. In addition, we described a tumor-centric regulatory network based on intercellular communication in TME. Together, our findings represent a unique resource for deciphering tumor heterogeneity of ACP, which will improve clinical diagnosis and treatment strategies.

BACKGROUNDThere is controversy over the effects of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) on the prognosis in patients with coronavirus disease 2019 (COVID-19), therefore, we aim to further explore the effect of renin–angiotensin–aldosterone system inhibitors on COVID-19-associated disease severity and mortality.METHODSWe systematically searched PubMed, Embase, Cochrane Library databases, medRxiv, and bioRxiv from inception to 6 September 2021. The primary outcome was all-cause mortality. Secondary outcome was severe disease which was defined as admission to the intensive care unit, the use of noninvasive or invasive mechanical ventilation, or death.RESULTSA total of 7 randomized controlled trials involving 1,321 COVID-19 patients were included. Fixed-effects meta-analysis demonstrated that the use of ACEI/ARB was not associated with higher risk of mortality (risk ratio [RR] = 0.84, 95% confidence interval [CI] 0.57–1.22, P = 0.10, I2 = 43%) and disease severity (RR = 0.86, 95% CI 0.71–1.05, P = 0.11, I2 = 47%). However, the subgroup analysis showed that compared with no ACEI/ARB use, the use of ARB was associated with a significant reduction of mortality (RR = 0.23, CI 0.09–0.60, P = 0.55, I2 = 0%) and disease severity (RR = 0.38, CI 0.19–0.77, P = 0.007).CONCLUSIONSIn conclusion, based on the available data, ACEI/ARB is not associated with the risk of mortality and disease severity in COVID-19 patients. And ACEI/ARB medications, especially ARB, should not be discontinued for patients with COVID-19.

An increasing number of patients with autoimmune hepatitis (AIH)-induced cirrhosis and variceal bleeding are currently referred for transjugular intrahepatic portosystemic shunt (TIPS). The aim of this study was to evaluate the safety and efficacy of TIPS in such patients, and to compare these results with data from patients with hepatitis B virus (HBV)-induced cirrhosis.This retrospective study consisted of 211 patients between August 2016 and May 2021, and patients were allocated to AIH (n = 35) and HBV (n = 176) groups according to the etiology of the cirrhosis. The primary endpoint was mortality after TIPS use; the secondary endpoints were recurrent bleeding, overt hepatic encephalopathy (OHE), shunt dysfunction, and dynamic changes in liver function over time.During a median follow-up period of 27 months, 23 (10.9%) patients died, 22 (10.4%) experienced recurrent bleeding, 50 (23.7%) experienced OHE, and 25 (11.8%) developed shunt dysfunction. Compared with the HBV group, the AIH group exhibited a similar mortality risk (adjusted hazard ratio, HR 1.199; 95% confidence interval, CI 0.367-3.917; p = 0.764), OHE (adjusted HR 1.023, 95% CI 0.483-2.167, p = 0.954), and shunt dysfunction (adjusted HR 0.862, 95% CI 0.285-2.610, p = 0.792); but a higher risk of recurrent bleeding (adjusted HR 2.731, 95% CI 1.112-6.708, p = 0.028). The dynamic changes in liver function manifested an initial trend toward deterioration, and then subsequent recovery in both the AIH and HBV groups.TIPS is a safe and effective treatment, and should be considered for those patients with AIH-induced cirrhosis and variceal bleeding.

Objective. To evaluate the efficacy and safety of programmed cell death receptor-1 (PD-1)/programmed cell death-ligand protein-1 (PD-L1) inhibitors in triple-negative breast cancer (TNBC) to provide a treatment basis for TNBC. Methods. Published case-control studies on PD-1/PD-L1 inhibitors in the treatment of TNBC were retrieved from PubMed, Embase, and Cochrane Library databases, and collected data were processed by RevMan 5.4. Results. A total of 7 studies with 4340 study subjects were obtained, including 2092 PD-L1-negative cases, 1375 PD-L1-positive cases, and 847 PD-L1 unidentified cases. The use of PD-1/PD-L1 inhibitors showed no significant impact on patients’ progression-free survival (PFS) and overall survival (OS). The use of PD-1/PD-L1 inhibitors in the PD-L1-positive subgroup significantly improved patients’ PFS and OS. Treatment with PD-1/PD-L1 inhibitors presented no significant effect on the incidence of adverse events (AEs) but increased the risk of AE grade ≥3 and severe AEs (SAEs). Conclusion. PD-1/PD-L1 inhibitors are effective in the treatment of TNBC, which is strongly correlated with the expression of PD-L1; patient selection and clinical application require further investigation and verification.

Aimed at greenhouse gas CO2 high value-added utilization, a N,N′-(propane-1,3-diyl)dipicolinamide (PPPA) supported Al(iii) metal–organic polydentate chelate complex (Al-PPPA) was designed and used to efficiently catalyze CO2 to cyclic carbonates.

According to the requirements for sustainable development, reclaiming fine chemicals from wastewater under mild conditions is an extremely significant line of research.

The Altaids is generally considered to be the largest Phanerozoic accretionary orogen on Earth, but it is unclear whether it was associated with extensive continental crustal growth and whether there is a link between the crustal growth and ore mineralization. This paper reviews whole-rock Nd and zircon Hf isotope data for felsic–intermediate–mafic igneous rocks in the Altaids and presents Nd + Hf isotopic contour maps for this region. The maps highlight the 3D lithospheric compositional architecture of the Altaids and make it possible to quantitatively evaluate the crustal growth and its relationship with ore deposits. The Altaids hosts ∼4 107 350 km2 and ∼184 830 750 km3 (assuming a crustal thickness of 40–50 km) juvenile crust (ϵNd(t) > 0), accounting for 58% by isotope-mapped area (∼7 010 375 km2) of almost all outcrops of the Altaids (∼8 745 000 km2) and formed during 1000–150 Ma (mainly 600–150 Ma). The juvenile crustal, slightly juvenile-reworked crustal and slightly reworked crustal provinces controlled the Cu–Au, the Pb–Zn–Ag and the Li–Be, Nb–Ta and W–Sn ore deposits. According to the crustal architecture and background of deep compositions, we propose that the ore deposits can be grouped into three types: juvenile crust-related, mixed-source (or slightly juvenile crust)-related and reworked crust-related. This highlights the close relationship between accretion, continental growth and mineralization, and will facilitate exploration for specific ore-deposit types in the Altaids.