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To screen transcription factor genes related to the prognosis of adult patients with sepsis.Twenty-three patients with sepsis and ten healthy individuals admitted for RNA-seq. Differential factors were enriched by four transcription factor databases, and survival analysis was adopted for core factors. Then, target genes were submitted to STRING to constitute the PPI network. Single-cell technology was used to localize cell lines. Finally, a transcription-target gene regulation network was constituted.A total of 4,224 DEGs were obtained between sepsis and NC groups. PPI results showed that FOXO3, NFKB1, SPI1, STAT5A, and PPARA were located in the center of the network. Target genes were related to cytokine-mediated signaling pathway and transcription regulator activity, etc. SPI1 was mainly located in monocyte cell lines, while FOXO3, PPARA, SP1, STAT3, and USF1 were expressed in monocyte cell lines, NK-T cell lines, and B cell lines. Compared with those in the control group, FOXO3, SP1, SPI1, STAT3, and USF1 were highly expressed in the sepsis group, while PPARA had low expression.Transcription factors such as FOXO3, PPARA, SP1, SPI1, STAT3, and USF1 are correlated with the prognosis of sepsis patients and thus may have a potential research value.Clinical Trial Registration: The clinical trial registration number is ChiCTR1900021261.

The results of best medical treatment (BMT), endovascular based treatment (EBT), and total arch replacement (TAR) with frozen elephant trunk (FET) treatment in a single centre experience were reported in non-A non-B aortic dissection patients.From January 2016 to May 2020, 215 consecutive patients with acute or subacute non-A non-B aortic dissection were enrolled. The primary endpoints were all cause death. Secondary endpoints included follow up adverse aortic event (AE), a composite of the outcomes of dissection related death, rupture, retrograde type A aortic dissection, stent graft induced new entry tear, secondary endoleak, and follow up re-intervention. Kaplan-Meier curves were used to evaluate associations between different treatments and outcomes.Among the 215 dissection patients, 127 (59.1%) received EBT, 42 (19.5%) received TAR + FET, and the remaining 46 (21.4%) received BMT. Thirty day mortality was higher in patients receiving TAR + FET (7.1%) than in those treated with EBT (1.6%) or BMT (2.2%) (p = .12). However, after a median follow up of 39.1 (27.0 - 50.7) months, no additional death was recorded in the TAR + FET group, while nine (7.3%) patients died in the EBT group and 14 (31.8%) died in the BMT group (p.001). Specifically, EBT and TAR + FET showed no significant difference in midterm mortality rate, follow up AE, and re-intervention for complicated or uncomplicated dissection patients involving zone 2. For patients with uncomplicated non-A non-B aortic dissection involving zone 2, EBT could profoundly decrease the mortality rate, follow up AE and re-intervention when compared with BMT (p.010 for all), although this difference was not statistically significant between TAR + FET and BMT. No statistical comparison was performed in patients with zone 1 involvement because of the limited number of patients.It was demonstrated that EBT or TAR + FET might be a viable strategy for non-A non-B aortic dissection patients.

Yunnan Baiyao is a well-known traditional Chinese medicine that can be formulated into a powder or capsule form. The mechanism by which it exerts its anti-inflammation effect, which is used in skin care products, needs to be further explored. In this study, we established the Staphylococcus aureus-induced mouse skin inflammatory model to investigate the effects of Yunnan Baiyao by the method of RNA-sequencing technology. The mice were randomly assigned to three groups, and those were control, model, and the Yunnan Baiyao-treated (YNtreated) group. Key genes and pathways were identified using bioinformatics analyses. In the study, we obtained 1,053 differentially expressed genes (DEGs) induced by Yunnan Baiyao. The 233 upregulated genes were enriched in 32 GO terms and 5 KEGG pathways, focused on the items, such as wound healing, cell metabolism, and proliferation, indicating the accelerating effects of Yunnan Baiyao on these aspects. The 820 downregulated genes were enriched mainly in the items, including the regulation of inflammation factor production, immune responses, and regulation of structure dermal components. Besides, Yunnan Baiyao reversed the expressions of 277 (201 decreased and 76 increased DEGs, respectively) induced by S. aureus. Ten key regulatory nodes (MMP2, PLK1, CCNB1, TLR4, CDK1, CCNA2, CDC25C, PDGFRA, MYOC, and KNG1) were identified by the construction of the protein interaction network, half of which were related to cell proliferation. VAV1 was another hub node that was affected by Yunnan Baiyao (Top 20). In the study, VAV1 and TLR4 can be considered key module genes in inflammation regulation. In conclusion, this study found that Yunnan Baiyao can significantly relieve inflammatory symptoms by regulating genes and pathways involved in the regulation of inflammation and immune response and also helped to deepen our understanding of the associated molecular mechanisms.

Two-dimensional (2D) ferroelectric transistors hold unique properties and positions, especially talking about low-power memories, in-memory computing, and multifunctional logic devices. To achieve better functions, appropriate design of new device structures and material combinations is necessary. We present an asymmetric 2D heterostructure integrating MoTe2, h-BN, and CuInP2S6 as a ferroelectric transistor, which exhibits an unusual property of anti-ambipolar transport characteristic under both positive and negative drain biases. Our results demonstrate that the anti-ambipolar behavior can be modulated by external electric field, achieving a peak-to-valley ratio up to 103. We also provide a comprehensive explanation for the occurrence and modulation of the anti-ambipolar peak based on a model describing linked lateral-and-vertical charge behaviors. Our findings provide insights for designing and constructing anti-ambipolar transistors and other 2D devices with significant potential for future applications.

Fei Wang,1– 3,* Jitao Liu,1– 3 Quan An,1– 4,* Yiming Wang,1– 3 Yang Yang,1– 3 Tong Huo,1– 3 Simin Yang,5 Ruijun Ju,5 Qianghua Quan1– 4 1Research and Development Department, Yunnan Baiyao Group Health Products Co., Ltd., Kunming, People’s Republic of China; 2East Asia Skin Health Research Center, Beijing, People’s Republic of China; 3Research and Development Department, REAL DermaSci & Biotech Co., Ltd., Beijing, People’s Republic of China; 4Research and Development Department, Yunnan Baiyao Group Shanghai Science & Technology Co., Ltd., Shanghai, People’s Republic of China; 5Beijing Key Laboratory of Enze Biomass Fine Chemicals, Department of Pharmaceutical Engineering, Beijing Institute of Petrochemical Technology, Beijing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Qianghua Quan, Yunnan Baiyao Group Health Products Co., Ltd, Kunming, People’s Republic of China, Email 18811781508@163.comIntroduction: Inflammation generally refers to the body’s defensive response to stimuli, and skin inflammation is still one of the major problems that affect human physical and mental health. While current pharmacological treatments are reported to have cytotoxicity and various side effects, herbal medicines with few side effects and low cytotoxicity are considered as alternative therapeutic approaches.Methods: In order to investigate anti-inflammatory effects and mechanisms of ALOE, the potential cytotoxicity of A. vera extracts (ALOE) was determined in vitro at first. The production of the pro-inflammatory proteins (ie, IL-6, TNF-α) in lipopolysaccharides (LPS) and ultraviolet A (UVA)-stimulated HaCaT and RAW264.7 cells were then treated with ALOE to test its inhibitory effects using enzyme-linked immunosorbent assay (ELISA). To further explore the anti-inflammatory mechanisms of ALOE, quantitative Polymerase Chain Reaction (qPCR) was used to analyze the mRNA expression of inflammatory genes iNOS, COX-2 and NO production. For NF-κB and MAPK signaling pathways analysis, Western blotting and nuclear fluorescence staining were used to evaluate the expression of key factors.Results: ALOE did not exhibit obvious cytotoxicity (0– 3 mg/mL) in vitro. ALOE was able to inhibit the expression of pro-inflammatory cytokines IL-6, TNF-α and functioned more prominently in LPS-induced model. ALOE could also suppress the mRNA expression of LPS-induced iNOS and COX-2 and further down-regulate NO level. Furthermore, ALOE reduced the protein expression of P65 in NF-κB signaling pathway and suppressed LPS-induced activation of ERK and JNK, instead of p38 MAPK pathway.Conclusion: Taken together, these results demonstrated that ALOE is a potential treatment in suppressing LPS-stimulated inflammation reactions targeting NF-κB, JNK and ERK signaling pathways. The anti-inflammatory effects of ALOE indicated that it has the potential to become an effective cosmetic ingredient.Keywords: Aloe vera extracts, anti-inflammation, LPS, iNOS, COX-2, NO, P65, MAPK, NF-κB

Fresh fruits and vegetable products are easily perishable during postharvest handling due to enzymatic browning reactions. This phenomenon has contributed to a significant loss of food. To reveal the physiological changes in fresh-cut potato tubers at the molecular level, a transcriptome analysis of potato tubers after cutting was carried out. A total of 10,872, 10,449, and 11,880 differentially expressed genes (DEGs) were identified at 4 h, 12 h and 24 h after cutting, respectively. More than 87.5% of these DEGs were classified into the categories of biological process (BP) and molecular function (MF) based on Gene Ontology (GO) analysis. There was a difference in the response to cutting at different stages after the cutting of potato tubers. The genes related to the phenol and fatty biosynthesis pathways, which are responsible for enzymatic browning and wound healing in potato tubers, were significantly enriched at 0–24 h after cutting. Most genes related to the enzymatic browning of potato tubers were up-regulated in response to cut-wounding. Plant hormone biosynthesis, signal molecular biosynthesis and transduction-related genes, such as gibberelin (GA), cytokinin (CK), ethylene (ET), auxin (IAA), jasmonic acid (JA), salicylic (SA), and Respiratory burst oxidase (Rboh) significantly changed at the early stage after cutting. In addition, the transcription factors involved in the wound response were the most abundant at the early stage after cutting. The transcription factor with the greatest response to injury was MYB, followed by AP2-EREBP, C3H and WRKY. This study revealed the physiological changes at the molecular level of fresh-cut potato tubers after cutting. This information is needed for developing a better approach to enhancing the postharvest shelf life of fresh processed potato and the breeding of potato plants that are resistant to enzymatic browning.

To report the results of optimal medical treatment (OMT) and endovascular aortic repair (EVAR) in patients with uncomplicated isolated abdominal aortic dissection (IAAD).A retrospective review of 96 consecutive patients with uncomplicated IAAD (uIAAD) managed at a single tertiary vascular unit between January 2011 and July 2021 was conducted. Standard methods for univariate and survival analyses were used. The primary outcomes were all-cause mortality. Secondary end points included uIAAD progression, interventional complications, and follow-up aortic intervention.Initially, 53.1% of patients (51/96) were managed with OMT. No in-hospital deaths occurred. During follow-up, three patients died, and three and two patients who were initially managed with OMT subsequently required endovascular treatment and surgical management, respectively. Initially, 46.9% of patients (45/96) underwent EVAR. One patient died during hospital admission; nine patients had an endoleak after operation and one needed reintervention. Furthermore, during follow-up, five patients died; four patients needed reoperation, one surgery and three endovascular treatments. The overall long-term mortality was 8.4%, and follow-up aortic intervention rate was 9.5% (median follow-up, 54 months; interquartile range, 33-81 months) with no significant difference between groups. Of note, 12 patients (12.6%) suffered uIAAD progression, which was higher in the OMT group than EVAR group (10 [19.6%] vs 2 [4.5%]; P = .03).uIAAD may be managed safely by OMT with regular surveillance, despite the risk of disease progression. Compared with OMT, EVAR could significantly prevent uIAAD progression. For anatomically suitable patients with uIAAD progression and who are unresponsive to OMT, pre-emptive EVAR is a safe and feasible option.

Light-induced skin damage leads to cellular or molecular dysfunction, thus potentially causing different skin issues (e.g., skin aging, seborrheic dermatitis and pigmentation). Blue light, a potent visible light that was previously adopted for promoting skin regeneration, draws considerable concerns in the past several years due to their potential damage to the skins. In this work, we investigated the roles of blue light in skewing the functions of sebocytes - the major cells that compose the sebaceous gland - an important "active" neuro-immuno-endocrine organ in maintaining skin functions. For therapeutically purposes, we employed cannabidiol (CBD), a clinically used non-psychotropic phytocannabinoid, to revert blue-light-induced sebocytes dysfunctions, including intracellular lipid secretion, inflammation, reactive oxygen species (ROS) secretion, and cell cycles. At the cellular level, CBD reduced the blue-light-enhanced intracellular lipid secretion, decreased inflammation, down-regulated intracellular ROS production, and restored the skewed cell cycles in the sebocytes. In the intracellular mechanism, CBD inhibited the blue-light-induced pro-apoptotic activity through rebalance BCL-2/BAX expression and down-regulated the NF-κB p65 pathway. Collectively, this study demonstrated that CBD was a potent therapeutic agent for maintaining normal sebocytes functions, thus is a promising drug for skincare purposes, especially considering its effectiveness in restoring the twisted sebocytes behaviors.

Jitao Liu,1,&ast; Fan Yang,2,&ast; Songyuan Luo,1,&ast; Chenxi Li,3 Weijie Liu,4 Yuan Liu,1 Wenhui Huang,1 Enmin Xie,5 Lyufan Chen,6 Sheng Su,5 Xinyue Yang,6 Qingshan Geng,1 Jianfang Luo1,5 1Department of Cardiology, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of Coronary Heart Disease Prevention, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People’s Republic of China; 2Department of Emergency and Critical Care Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People’s Republic of China; 3Department of Cardiac Surgery Intensive Care Unit, Guangdong Cardiovascular Institute, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People’s Republic of China; 4Center for Information Technology and Statistics, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 5The Second School of Clinical Medicine, Southern Medical University, Guangzhou, People’s Republic of China; 6School of Medicine, South China University of Technology, Guangzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Jianfang Luo; Qingshan GengDepartment of Cardiology, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of Coronary Heart Disease Prevention, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, #106 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510080, People’s Republic of ChinaTel +86-20-83827812Fax + 86-20-83875453Email jianfangluo@sina.com; gengqingshan@gdph.org.cnPurpose: The present study aimed to investigate the incidence and predictors of post-operative delirium (POD) in patients with complicated type B aortic dissection (TBAD) undergoing TEVAR with/without concomitant procedures and to assess the association of POD with early and follow-up outcomes.Methods: A retrospective single-center cross-sectional analysis was conducted using a prospectively maintained database from 2010 to 2017. Outcomes were postoperative clinical outcomes, early and follow-up survival.Results: A total of 517 complicated TBAD patients were enrolled. POD was observed in 13.3% (69/517) patients and was associated with increased hospital length of stay (LOS) and hospital costs (P< 0.001 for both). Besides, POD was found to be an independent risk factor for prolonged ICU stay (odds ratio [OR] 4.39, 95% confidence interval [CI] 2.40– 8.01, P< 0.001) and early death (OR 4.42, 95% CI 1.26– 15.54, P= 0.020). Predictors of POD were hybrid procedure (OR 2.17, 95% CI 1.20– 3.92, P= 0.010), the use of benzodiazepine (OR 1.86, 95% CI 1.07– 3.23, P= 0.027) or quinolone (OR 2.35, 95% CI 1.26– 4.38, P= 0.007), creatinine > 2 mg/dL (OR 3.25, 95% CI 1.57– 6.72, P= 0.001) and preoperative blood transfusion (OR 3.31, 95% CI 1.76– 6.21, P< 0.001). After a median follow-up of 73.6 months, POD remained as an independent indicator for follow-up mortality (hazard ratio [HR] 2.40, 95% CI 1.31– 4.38, P= 0.005) after adjusting potential confounders.Conclusion: POD after TEVAR has an incidence of around 13% and could profoundly increase the in-hospital LOS, hospital costs, as well as the early and follow-up mortality. A series of risk factors, including hybrid procedure, the use of benzodiazepine or quinolone, creatinine > 2 mg/dL and preoperative blood transfusion, were identified as independent risk factors for POD. Effective risk-stratification and patient-tailored management strategy should be developed to reduce the incidence of POD.Keywords: type B aortic dissection, thoracic endovascular aortic repair, hybrid procedure, postoperative delirium, predictors, outcomes

OBJECTIVES This study aimed to investigate the morphological evolution and risk stratification of ulcer-like projection (ULP) in patients with uncomplicated acute type B aortic intramural haematoma. METHODS A retrospective study was conducted on patients with uncomplicated acute type B intramural haematoma admitted in our institution from January 2015 to June 2020. The primary end points were adverse aortic events (AAE), including aortic rupture, aortic dissection, aortic aneurysm and ULP enlargement. RESULTS The study cohort comprised 140 patients, including 62 (44%) and 78 (56%) patients with and without initial ULP, respectively. AAE occurred in 13 patients (9%) in the early term and 42 patients (33%) in the mid-term. Compared with patients without ULP, patients with initial ULP had no significant difference in early outcomes but a higher mid-term AAE rate [8% vs 11%, odds ratio (OR) 1.5, P = 0.47; 17% vs 55%, OR 6.0, P CONCLUSIONS High-risk ULP is a rapidly evolving entity and a marker of AAE despite optimal medical therapy. Therefore, close follow-up and prompt intervention are recommended for patients with high-risk ULP.

Introduction: Inflammation generally refers to the body’s defensive response to stimuli, and skin inflammation is still one of the major problems that affect human physical and mental health. While current pharmacological treatments are reported to have cytotoxicity and various side effects, herbal medicines with few side effects and low cytotoxicity are considered as alternative therapeutic approaches. Methods In order to investigate anti-inflammatory effects and mechanisms of ALOE, the potential cytotoxicity ofA. veraextracts (ALOE) was determinedin vitroat first. The production of the pro-inflammatory proteins (i.e. IL-6, TNF-α) in lipopolysaccharides (LPS) and ultraviolet A (UVA)-stimulated HaCaT and RAW264.7 cells were then treated with ALOE to test its inhibitory effects using enzyme-linked immunosorbent assay (ELISA). To further explore the anti-inflammatory mechanisms of ALOE, quantitative Polymerase Chain Reaction (qPCR) was used to analyze the mRNA expression of inflammatory genesiNOS、COX-2and NO production. For NF-κB and MAPK signaling pathways analysis, western blotting and nuclear fluorescence staining were used to evaluate the expression of key factors. Results ALOE did not exhibit obvious cytotoxicity (0–3 mg/mL)in vitro. ALOE was able to inhibit the expression of pro-inflammatory cytokines IL-6, TNF-α and functioned more prominently in LPS-induced model. ALOE could also suppress the mRNA expression of LPS-inducediNOSandCOX-2and further down-regulate NO level. Furthermore, ALOE reduced the protein expression of P65 in NF-κB signaling pathway and suppressed LPS-induced activation of ERK and JNK, instead of p38 MAPK pathway. Conclusions Taken together, these results demonstrated that ALOE is a potential treatment in suppressing LPS-stimulated inflammation reactions targeting NF-κB, JNK and ERK signaling pathways. The anti-inflammatory effects of ALOE indicated that it has the potential to become an effective cosmetic ingredient.

OBJECTIVES The aim of this work was to investigate the impact of machine-learning-derived baseline lean psoas muscle area (LPMA) for patients undergoing thoracic endovascular aortic repair. METHODS A retrospective study was undertaken of acute and subacute complicated type B aortic dissection patients who underwent endovascular treatment from 2010 to 2017. LPMA (a marker of frailty) was calculated by multiplying psoas muscle area and density measured at L3 level from the computed tomography. The optimal cut-off value of LPMA was determined by the Cox hazard model with restricted cubic spline. RESULTS A total of 428 patients who met the inclusion criteria were included in this study. Patients were classified into low LPMA group (n = 218) and high LPMA group (n = 210) using the cut-off value of 395 cm2 Hounsfield unit. An automatic muscle segmentation algorithm was developed based on U-Net architecture. There was high correlation between machine-learning method and manual measurement for psoas muscle area (r = 0.91, P CONCLUSIONS Baseline LPMA could profoundly affect the prognosis of patients undergoing thoracic endovascular aortic repair. It was feasible to integrate the automatic muscle measurements into clinical routine.

Objective This study aimed to determine the effect of intervention timing, from symptom onset to thoracic endovascular aortic repair (TEVAR), on early and late outcomes in high risk patients with uncomplicated type B aortic dissection (uTBAD). Methods The study retrospectively evaluated 267 uTBAD patients with high risk radiographic features who underwent pre-emptive TEVAR during the acute and subacute periods. Demographics, comorbidities, pre-operative imaging features, peri-procedural details, and follow up outcomes were analysed. Results Among the 267 pre-emptive TEVARs for high risk uTBAD, 130 were performed in the acute phase (1–14 days); and 137 in the subacute phase (15–90 days), from initial presentation. The mean age was 55.9 ± 11.0 years and 222 (83.1%) were men. The 30 day mortality rate in the acute group was five times higher than that in the subacute group (3.8% vs. 0.7%), although without statistically significant difference (p = .11). No statistically significant difference in 30 day outcomes (aortic rupture, retrograde type A dissection [RTAD], immediate type Ia endoleak, stroke, spinal cord ischaemia, and re-intervention) was noted (p > .05 for each). Of note, aortic rupture, RTAD, and disabling stroke were observed only in the acute group. Multivariable logistic analyses showed that intervention timing was not associated with 30 day outcomes. The median clinical follow up was 48.2 ± 25.9 months (range 1 – 106 months). There were no significant differences in all cause mortality, dissection related death, late intervention, or aortic related late events among timing cohorts (p > .05 for each). Furthermore, aortic remodelling, by analysing the flow status of the false lumen and evaluation of aortic diameters, either at the thoracic aorta level or the abdominal aorta level, was similar between the two groups. Multivariable Cox analyses showed that intervention timing was not associated with late outcomes. Conclusion The present study indicates that TEVAR for high risk uTBAD in the acute phase was associated with a trend toward higher rates of early complications, while the long term outcomes were comparable with those of the subacute phase.

When a Pelton turbine operates in sand laden water, the abrasive wear of its overflow components by high-speed jets is serious. Based on the VOF (volume of fluid) multiphase flow model, the SST (shear stress transfer) k-ω turbulence model, the particle motion Lagrangian model, the generic wear model, and the SIMPLEC (Semi-Implicit Method for Pressure Linked Equations Consistent) algorithm, the liquid–air–solid three-phase flow in the key overflow components of a Pelton turbine were simulated, the abrasive wear was predicted, and the internal sand-water flow characteristics and the abrasive wear of the overflow components were analyzed. The results show that the trailing edge at the root of the runner bucket, the leading face of the bucket near the root, the notch, and the splitter are severely worn. The abrasive wear of the splitter and the notch is more severe than that of the leading face of the bucket. The wear rate from the splitter to the trailing edge increases first and then decreases. The wear pattern of the needle tip is mainly “dotted”, while that of the nozzle opening is “flaky”, and the abrasive wear of the nozzle opening is more severe than that of the needle. The predicted results are consistent with the actual conditions at the site of the power station. This study provides a technical method for the prediction of abrasive wear of the Pelton turbine and a technical basis for the operation and maintenance of the power station.

Based on the solid–liquid two-phase flow model, SST k-ω model, and Lagrangian equation model of particle motion, numerical simulations of the sediment–water flow in the injector of a large Pelton turbine were conducted. The distribution rules of pressure, velocity, erosion rate, and erosion location of the injector were obtained by analyzing the sediment–water flow characteristics and sediment erosion distribution characteristics of the injector. The results revealed that the velocity distribution trend of the water inside the cylindrical jet exhibited a nonlinear distribution, and the phenomenon of “velocity deficit” occurred at the end of the needle guide and needle tip, resulting in a decrease in the jet quality of the injector. The sediment particle diameter affected the erosion rate of the needle and erosion location of the needle and nozzle port ring. This study provided guidance for sediment erosion analysis and the prediction of the utility of large Pelton turbines.

Titanium beryllide, Be12Ti, has been proposed as a prospective neutron multiplier in fusion reactors. First-principles calculations have been performed to investigate the nucleation mechanism of a He bubble in bulk Be12Ti. Meanwhile, the influence of the presence of H atoms on the nucleation of the He bubble, i.e., the synergistic effect of He and H atoms, has also been investigated. It has been found that the He bubble will initially nucleate around a monovacancy (VBe2). When more He atoms have been implanted, two newly induced vacancies (VBe1 and VBe3) could be successively observed. The nucleation of the He bubble will occur around the divacancy of VBe2VBe1 and the trivacancy of VBe2VBe1VBe3. Dumbbell structures in the He bubble evolve with the number of implanted He atoms and finally disappear. The presence of H atoms will significantly influence the nucleation of the He bubble. It is interesting that some tetrahedral and octahedral structures have also been observed. The maximal number of H atoms trapped by a He bubble has been obtained. These phenomena could be further explained by the continuous shrinking of the isosurface of charge density. The present results provide a microscopic physical foundation to understand the mechanism of He and H atoms retention in neutron multiplier materials. This investigation could be helpful for the design and fabrication of more promising beryllides which could withstand a severe external environment.

First-principles calculations have been performed to investigate the interaction between solute impurity O and H/He/vacancy irradiation defects in Ti3AlC2. The formation energy and occupation of O atoms within different defects as well as the trapping progress of O/H clusters are discussed. It is found that the O atom preferentially occupies the hexahedral interstitial site (Ihex-1) in bulk Ti3AlC2, whereas it prefers to occupy the neighbouring tetrahedral interstitial site (Itetr-2) within pre-exisiting Al monovacancy (VAl), Al divacancy (2VAl–Al) and the 2VAl–C divacancy composed of Al and C vacancies. The appearance of C vacancy could greatly reduce the oxygen formation energy and make an O atom more inclined to occupy the center of C vacancy. Vacancy could capture more O atoms than H/He atoms, where VAl and 2VAl–Al could hold up to fifteen and eighteen O atoms, respectively. Meanwhile, the O could also promote the formation of Al vacancy. On the other hand, O atoms tend to occupy the interstitial sites near the Al atomic layer and have attraction to Al atoms, which is likely to enable the O atoms to combine with the Al atoms to form a Al2O3 protective layer, thus effectively inhibiting further oxidation inside the Ti3AlC2. In addition, the H–O exhibits repulsion interaction, but strong attraction occurs in the He–O interaction. Therefore, the O atom has an inhibitory effect on the formation of the H cluster, while it could bind more He atoms to form a large number of He bubbles. Besides, the O impurity greatly reduces the trapping ability of vacancy to H atoms, and O and He have a synergistic interaction for inhibiting the aggregation of H clusters. The present results are expected to provide a new insight into the behaviour of Ti3AlC2 under irradiation and oxidation conditions so that structural materials could be better designed.

OBJECTIVES Our goal was to investigate the accuracy of the two-dimensional and three-dimensional computed tomography imaging features in predicting the progression of acute uncomplicated type B aortic intramural haematoma (IMH). METHODS This study retrospectively screened 140 patients diagnosed with acute uncomplicated type B IMH in our institution from January 2015 to December 2020. Patients were classified as exhibiting progression (aortic dissection, aortic rupture, aneurysm formation, ulcer-like projection depth >10 mm or >10% increase in the initial thickness of the aortic wall) and regression (completely or partially reabsorbed haematoma) based on follow-up computed tomography. RESULTS During the 11.4-month follow-up [interquartile range (IQR), 2.6–17.8], 55 patients had haematoma progression. The progression group had higher haematoma volume (HV) and total lesion volume [94.8 (IQR, 80.0–108.2) cm3 vs 40.3 (IQR, 30.8–57.9) cm3; 278.0 (IQR, 238.6–369.3) cm3 vs 197.3 (IQR, 152.8–235.9) cm3, both P < 0.001) and longer lesion length [43.2 (IQR, 37.5–46.7) cm vs 30.4 (IQR, 28.1–37.6) cm, P < 0.001)] than the regression group. According to the area under the curve, HV > 66 cm3 is the greatest risk factor for haematoma progression. In multivariable analysis, HV was a powerful independent predictive factor for type B IMH progression, with a hazard ratio of 17.9 (95% confidence interval, 5.5–58.7; P < 0.001). CONCLUSIONS Volumetric parameters may help to predict disease progression more precisely for patients with acute uncomplicated type B IMH compared to standard axial measurements, which might optimize the initial treatment and follow-up protocol.