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This research investigates the effects of Na2SO4 and Na2CO3 on the mechanical and hydration properties of high-volume fly ash (FA) cement (HFC) at three curing temperatures: 25°C, 40°C, and...

Background: This study employed three surgical techniques: total arch replacement (TAR) with frozen elephant trunk (FET), aortic balloon occlusion technique (ABO) and hybrid aortic arch repair (HAR) on patients with type I aortic dissection in Fuwai Hospital, aiming to compare the early outcomes of these surgical armamentariums.Methods: From January 2016 to December 2018, an overall 633 patients (431 of TAR+FET, 122 of HAR, and 80 of ABO) with type I aortic dissection were included in the study. Thirty-day mortality, stroke, paraplegia, re-exploration for bleeding, and renal replacement therapy were compared using the matching weight method (MWM).Results: After MWM process, the baseline characteristics were comparable among three TAR groups. It showed that ABO group had the longest cardiopulmonary bypass (p < 0.001) and aortic cross-clamp time (p < 0.001), while the operation time was longest in the HAR group (p = 0.039). There was no significant difference in 30-day mortality among groups (p = 0.783). Furthermore, the incidence of stroke (p = 0.679), paraplegia (p = 0.104), re-exploration for bleeding (p = 0.313), and CRRT (p = 0.834) demonstrated no significant difference. Of note, no significant differences were found regarding these outcomes even before using MWM.Conclusions: Based on the early outcomes, the three TAR approaches were equally applicable to type I aortic dissection. We may choose the specific procedure relatively flexibly according to patient status and surgeon's expertise. Importantly, long-term investigations are warranted to determine whether above approaches remain to be of equivalent efficacy and safety.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer with high incidence and mortality. MiR-597-5p is downregulated in tumor tissues of HCC compared with non-tumor tissues. However, its role in HCC is still unknown. This study aims to assess the function of miR-597-5p in HCC development and investigate the underlying mechanism. To perform gain- and loss-of-function studies, SK-HEP-1 cells and Huh-7 cells were transfected with miR-597-5p mimics and inhibitor, respectively. MiR-597-5p markedly reduced the cell viability and the expression of Ki-67 in HCC cells. MiR-597-5p also repressed the cell cycle progression of HCC cells and the protein levels of cyclin D1 and CDK2. Moreover, miR597-5p inhibited the migration and invasion of HCC cells and decreased MMP2 and MMP9 levels. Transcriptional enhancer associate domain transcription factor 1 (TEAD1) was identified as a target of miR-597-5p by luciferase reporter assay. TEAD1 and its downstream target genes, CTGF and CYR61, were downregulated by miR-597-5p in HCC cells. Furthermore, miR-597-5p was demonstrated to function in HCC progression by targeting TEAD1 via TEAD1 expression gain and loss. Our study demonstrates that miR-597-5p represses the proliferation, migration, and invasion of HCC cells through targeting TEAD1, which provides a therapeutic target for HCC treatment.

Aims: Real-time quantitative polymerase chain reaction (RT-qPCR) is the standard assay used for revealing the gene expression characteristics. However, the RT-qPCR studies all need reference genes for normalization to make the results comparable, which should hold a high expression stability during all experimental datasets. So far, there was no optimal set of reference genes identified in mice left ventricles (LV) across embryonic and postnatal stages. The objective of our research was to identify the appropriate reference genes in mice LV from different developmental stages.Methods and Results: we investigated the gene expressions of common 21 candidate housekeeping genes in mice LV from 7 different developmental stages, almost throughout the whole period of the mouse lifespan. The expression of some candidate reference genes, such as 18S and Actb, apparently fluctuated. The stability of potential reference genes was evaluated by a number of methods, such as GeNorm, NormFinder, BestKeeper, Delta-Ct and RefFinder method. we identified a set of optimal reference genes that can be reliably used for normalization of RT-qPCR experiments in different developmental stages of mice LV. Our results showed that following genes should not be used as reference genes in mice LV development studies: 18S, Hmbs, Ubc, Psmb4, Tfrc and Actb. And the Rplp0 appeared to represent a good choice. Conclusions: Our study provides the expression stability of the commonly used reference genes in process of LV development and maturation. We also identified a set of optimal reference genes under different conditions. Our findings may be helpful in future studies to investigate the gene expression patterns and mechanism of mammalian heart development.

Aims: We previously found that complement components are upregulated in the myocardium of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), and inhibiting the complement receptor C5aR reduces disease severity in desmin knockout (Des-/- ) mice, a model for ARVC. Here, we examined the mechanism underlying complement activation in ARVC, revealing a potential new therapeutic target. Methods: First, immunostaining, RT-PCR and western blot were used to detect the expression levels of complement and coagulation factors. Second, we knocked out the central complement component C3 in Des-/- mice (ARVC model) by crossing Des-/- mice with C3-/- mice to explore whether complement system activation occurs independently of the conventional pathway. Then, we evaluated whether a targeted intervention to coagulation system is effective to reduce myocardium injury. Finally, the plasma sC5b9 level was assessed to investigate the role in predicting adverse cardiac events in the ARVC cohort. Results: The complement system is activated in the myocardium in ARVC. Autoantibodies against myocardial proteins provided a possible mechanism underlying. Moreover, we found increased levels of myocardial C5 and the serum C5a in Des-/-C3-/- mice compared to wild-type mice, indicating that C5 is activated independently from the conventional pathway, presumably via the coagulation system. Crosstalk between the complement and coagulation systems exacerbated the myocardial injury in ARVC mice, and this injury was reduced by using the thrombin inhibitor lepirudin. In addition, we found significantly elevated plasma levels of sC5b9 and thrombin in patients, and this increase was correlated with all-cause mortality. Conclusions: These results suggest that crosstalk between the coagulation and complement systems plays a pathogenic role in cardiac dysfunction in ARVC. Thus, understanding this crosstalk may have important clinical implications with respect to diagnosing and treating ARVC.

Abdominal aortic aneurysm (AAA) is potentially life threatening and characterized by immune-inflammatory cell infiltration and extracellular matrix degradation. Currently, pharmacotherapy mainly aims to control risk factors without reversion of the dilated aorta. This study analyzed the immune-inflammatory response and identified the immune-related hub genes of AAA.Gene Expression Omnibus datasets (GSE57691, GSE47472 and GSE7084) were downloaded. After identification of GSE57691 differentially expressed genes (DEGs), weighted gene co-expression network analysis of the DEGs was performed. Through enrichment analysis of each module and screening in Immunology Database and Analysis Portal, immune-related hub genes were identified via protein-protein interaction (PPI) network construction and lasso regression. CIBERSORT was utilized to analyze AAA immune infiltration. The correlations between the immune-related hub genes and infiltrating immune cells were investigated. Receiver operating characteristic (ROC) curve analysis was performed to determine immune-related hub gene cutoff values, which were validated in GSE47472 and GSE7084.In GSE57691, 1,018 DEGs were identified. Five modules were identified in the co-expression network. The blue and green modules were found to be related to immune-inflammatory responses, and 61 immune-related genes were identified. PPI and lasso regression analyses identified FOS, IL-6 and IL2RB as AAA immune-related hub genes. CIBERSORT analysis indicated significantly increased infiltration of naive B cells, memory activated CD4 T cells, follicular helper T cells, monocytes and M1 macrophages and significantly decreased infiltration of M2 macrophages in AAA compared with normal samples. IL2RB was more strongly associated with immune infiltration in AAA than were FOS and IL6. The IL2RB area under the ROC curve (AUC) value was 0.9 in both the training and validation set, demonstrating its strong, stable diagnostic value in AAA.AAA and normal samples had different immune infiltration statuses. IL2RB was identified as an immune-related hub gene and a potential hub gene with significant diagnostic value in AAA.

Defects, such as delamination and debonding, are critical to the performance of carbon fiber-reinforced polymer (CFRP) composites. In recent years, non-destructive testing techniques have been improved for the inspection of these defects among CFRPs. In this study, an all-optical and non-destructive laser ultrasonic technique with an optical microphone detection module has been presented to detect the artificial subsurface defects among the CFRP composites. A finite element simulation based on the thermo-mechanical coupling model was used to study the process of nanosecond pulsed laser excitation of the CFRP laminate to produce ultrasound and the propagation behavior of ultrasound among the CFRP laminate. A series of non-contact laser ultrasonic testing experiments were carried out to study the flat bottom holes of different sizes via a laser ultrasonic detection system. The artificial subsurface defects were reliably identified by the presented all-optical laser ultrasonic system imbedded in the optical microphone using four feature images.

Background Aortic arch disease with Kommerell's diverticulum is an uncommon but troublesome condition, and there are a variety of therapeutic modalities for treating this. We retrospectively analyzed cases who underwent open surgery to summarize different situations and approaches. Methods From November 2015 to January 2019, nine patients underwent operation for the mentioned disorder. Four patients with aortic dissection received total arch replacement. Two patients suffering from type B aortic dissection (TBAD) have accepted graft replacement from ascending aorta (aAO) to descending aorta. Two patients with true aneurysm and congenital malformation underwent graft bypass from aAO to descending aorta. One patient had graft replacement of descending aorta. Results There were nine (eight males and one female) patients with median age of 45 (from 14 to 54) years. The 30-day mortality was 11.1% (1 patient) due to refractory respiratory failure caused by compression of bronchus. One patient had complication of peripheral neuropathy and recovered eventually. Eight patients were followed-up for a median period of 20 [9-46] months. All patients were alive and had no long-term complications except one patient who received re-intervention due to delayed dilation of downstream aorta. Conclusions Treatment for different arch lesions with Kommerell's diverticulum should follow corresponding indications. Open surgery is the preferred choice and detailed therapeutic strategy depends on the extension of aneurysm, classification and phase of dissection. Stenting might cause airway compression when right-sided arch and vascular ring exist.

This study aimed to compare clinical outcomes of patients treated by total arch replacement (TAR) with frozen elephant trunk (FET), aortic balloon occlusion (ABO) technique and hybrid arch repair (HAR). Between January 2017 and July 2019, 643 consecutive patients with aortic arch diseases were eligible for TAR, including 356 in conventional FET, 112 in ABO based on FET, and 175 in HAR. A retrospective cohort analysis of perioperative results was undertaken, performed with inverse probability weighting. The primary endpoint was composite endpoints included 30-day mortality, stroke, paraplegia, hemodialysis, reintubation, and intra-aortic balloon pump or extracorporeal membrane oxygenation support, and visceral dysfunction was secondary endpoint. Overall in-hospital mortality was 2.2% (FET = 2.5% vs ABO = 0 vs HAR = 2.9%, P= 0.210). Parallel early outcomes were demonstrated among three groups. ABO group was associated with significantly shorter circulatory arrest time (5, IQR 3-7 vs 16, IQR 14-18 minutes, P0.001), and a lower incidence of visceral dysfunction compared with FET group (25.1% vs 47.3%, P= 0.003). Patients receiving ABO suffered a significantly lower rate of prolonged ventilation (more than 72 hours; P= 0.014). Furthermore, a tendency toward decreasing composite endpoints was suggested in ABO (7.2%) compared with FET (15.5%, P= 0.061) and HAR (19.8%, P= 0.032). ABO technique obtains considerable early clinical outcomes for TAR compared with conventional FET and HAR, which could be a feasible and effective approach for patients with aortic arch diseases.

We reported a rare case of iatrogenic aortic dissection caused by incorrect frozen elephant trunk (FET) deployment. A 53-year-old man underwent total arch replacement with FET for aortic arch aneurysm and concurrent PAU in the descending aorta. However, after FET deployment, aortic dissection occurred. We analyzed that the tip of FET stent had been inserted into the PAU and caused aortic dissection. We performed some salvage procedures. However, the patient died on the 1st postoperative day. Therefore, care should be taken to avoid incorrect deployment of FET when there is a large tear or ulcer lesion in the proximal descending aorta.

The repair of thoracoabdominal aortic aneurysm (TAAA) require a range of surgical techniques and is associated with serious complications such as paraplegia, gastrointestinal complications and acute kidney injury. In this report, we present a case of successful giant TAAA repair. Repair was performed from proximal to distal by sequential aortic cross clamp-and-sew under normothermia in this case. To prevent visceral, renal and spinal cord ischemia, organ protection was supplemented with cerebrospinal fluid drainage, renal perfusion and selective visceral perfusion in this case.

Background: There are no standardized treatments for giant cell tumors of the bone (GCTB) in rare locations such as the spine and pelvis or for those that are inoperable and recurrent, let alone for multicentric GCTB. This study reports a novel case of multicentric GCTB treated with a promising antiangiogenic drug, apatinib, a small-molecule tyrosine kinase inhibitor. The efficacy of apatinib in the treatment of GCTB has not been reported previously. Patients and Methods: A 27-year-old female presented with two giant cell tumors of the spine and sacrum–ilium diagnosed on December 15, 2016. Surgery and selective arterial embolization (SAE) were not reasonable options for this patient, and denosumab was unavailable; therefore, the antiangiogenic drug apatinib and the osteoclast inhibitor zoledronic acid were administered. Apatinib was initially administered at a dose of 850 mg daily, which was decreased to 425 mg daily after 7 months, and then increased again to 635 mg after 11 months. The patient was prescribed a maintenance dose of 500 mg daily after 16 months. The patient reported side effects of Grades I–III nausea, vomiting, and Grades II–III hand–foot syndrome. The patient underwent SAE at 26 months, and at that time, she was switched to denosumab instead of zoledronic acid. Results: The patient showed noticeable symptomatic improvement and visibly reduced tumor size after the first month of treatment. Computed tomography in the 4th month identified a partial response based on the RECIST criteria. The patient has achieved an objective reduction in tumor size at 32 months. Conclusions: Comprehensive treatment including apatinib represents a potential new treatment strategy for inoperable GCTB, with tolerable side effects. However, further clinical trials are now necessary to confirm an effective dose and determine the efficacy and safety of apatinib in the treatment of GCTB.

Background Obesity is dramatically increasing worldwide, and more obese patients may develop aortic dissection and present for surgical repair. The study aims to analyse the impact of body mass index (BMI) on surgical outcomes in patients with acute Stanford type A aortic dissection (ATAAD). Methods From January 2017 to June 2019, the clinical data of 268 ATAAD patients in a single centre were retrospectively reviewed. They were divided into three groups based on the BMI: normal weight (BMI 18.5 to 2, n = 110), overweight (BMI 25 to 2, n = 114) and obese (BMI ≥30 kg/m2, n = 44). Results There was no statistical difference among the three groups in terms of the composite adverse events including 30-day mortality, stroke, paraplegia, renal failure, hepatic failure, reintubation or tracheotomy and low cardiac output syndrome (20.9% vs 21.9% vs 18.2% for normal, overweight and obese, respectively; P = 0.882). No significant difference was found in the mid-term survival among the three groups. The proportion of prolonged ventilation was highest in the obese group followed by the overweight and normal groups (59.1% vs 45.6% vs 34.5%, respectively; P = 0.017). Multivariable logistic regression analysis suggested that BMI was not associated with the composite adverse events, while BMI ≥30 kg/m2 was an independent risk factor for prolonged ventilation (OR 2.261; 95% CI 1.056–4.838; P = 0.036). Conclusions BMI had no effect on the early major adverse outcomes and mid-term survival after surgery for ATAAD. Satisfactory surgical outcomes can be obtained in patients with ATAAD at all weights.

BACKGROUND: Organ dysfunction caused by hypothermic circulatory arrest continues to concern surgeons. The aortic balloon occlusion (ABO) technique can significantly shorten the circulatory arrest time in total arch replacement with frozen elephant trunk (TAR with FET). This study aims to analyze the renal protective effect of the ABO technique and to analyze the predictors of acute kidney injury (AKI) and continuous renal replacement therapy (CRRT) after TAR with FET. METHODS: Between August 2017 and September 2018, 247 patients who underwent TAR with FET were divided into ABO and moderate hypothermic circulatory arrest (MHCA) groups. The primary endpoint was postoperative AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Multivariable logistic analysis was used to identify the predictors of AKI and CRRT after TAR with FET. RESULTS: With the application of the ABO technique, the circulatory arrest time was significantly shortened (ABO 4, IQR: 3–6 vs. MHCA 18, IQR: 16–20, P

Objective To investigate the use of the aortic balloon occlusion technique to assist total aortic arch replacement (TAR) with frozen elephant trunk (FET) to shorten the lower body circulatory arrest (CA) time and raise the nadir temperature during cardiopulmonary bypass. Methods This retrospective study reviewed consecutive patients that underwent aortic balloon occlusion to assist TAR with FET and patients that received conventional TAR with FET procedures. Preoperative characteristics, perioperative characteristics and postoperative outcomes were compared between the two groups. Results The study included130 patients treated with aortic balloon occlusion and 230 patients treated with conventional TAR with FET. The 30-day mortality rate was similar between the aortic balloon occlusion and conventional groups (4.62% versus 7.83%, respectively). Multivariate analysis showed that aortic balloon occlusion reduced the incidence of acute kidney injury, hepatic injury and red blood cell transfusion. The application of aortic balloon occlusion reduced the mean ± SD CA time from 17.24 ± 4.36 min to 6.33 ± 5.74 min, with the target nadir nasal temperature being increased from 25°C to 28°C. Conclusion The aortic balloon occlusion technique achieved significant improvements in reducing complications, but this did not translate into lower 30-day mortality.

This paper develops a two-dimensional array pyrometer, which can measure the true temperature field of the two-dimensional array. The pyrometer consists of an optical part, a circuit part and a software part. In the optical part, the radiation energy of the two-dimensional array target is obtained by scanning with the rotating mirror. Then, the radiation signal is converted and amplified by the circuit part. The software component realizes the functions of the pyrometer calibration, signal acquisition and data processing. The data processing adopts the secondary measurement method to calculate the true temperature and uses the multi-threaded method to improve the operational efficiency. Experiments show that the uncertainty of the two-dimensional pyrometer array can reach 1.43%. Compared with the single-threaded method, the true temperature operation time of the two-dimensional pyrometer array is improved by 77%, which verifies that the software operational efficiency is greatly improved.

Electrical parameters (saturation current density and local series resistance) are critical to solar cells. In this work, 2-dimensional finite-element simulations were carried out to study the influence of local distributions of electrical parameters and broken fingers on luminescence images at various working conditions. The relationship between luminescence intensity and local diode implied voltage was identified by simulation results and also by lock-in carrierography/photoluminescence measurements on a silicon solar cell. Spatially resolved saturation current density (J0) and local series resistance (Rs) of the Si solar cell were realized by LIC. Influences of broken fingers on J0 and Rs were discussed. The LIC measurements were in accordance with 2D simulation results. The experiment results show that LIC, as a quantitative luminescence-based methodology, can be able to spatially resolve electrical parameters of silicon solar cells and PV modules.

Background Many patients required secondary open arch operation due to new aortic pathologies or complications after thoracic endovascular aortic repair (TEVAR). In this study, we investigated the outcome of secondary open arch operation after prior TEVAR. Methods Fifty-seven consecutive patients underwent secondary open arch operation after prior TEVAR. The major indications were retrograde type A aortic dissection (n = 24), proximal new aortic dissection (n = 8), and type Ⅰa endoleak (n = 16). An elective operation was performed in 35 patients and an emergent operation in 22. The survival and freedom from aortic events during the follow-up were evaluated with the Kaplan-Meier survival curve and the log-rank test. The survival was also analyzed with the Cox analysis. Results The in-hospital mortality was 7.0% (4 of 57). The mean follow-up time was 32.2 ± 19.7 months. Five late deaths occurred. The overall survival at 1 year, 3 years, and 6 years was 89.5%, 84.6%, and 79.9%, respectively. Aortic events developed in 7 patients. Freedom from aortic events after the operation at 1 year, 3 years, and 6 years was 94.2%, 83.0%, and 77.8%, respectively. There were no differences in survival and freedom from aortic events between the elective group and the emergent group. The Cox analysis identified additional coronary artery bypass grafting and hypothermic circulatory arrest as independent factors predicting survival. Conclusions Secondary open arch operation could be performed to treat the arch pathologies after TEVAR with acceptable early and midterm outcomes.

In this study, we investigated the mechanism of photosynthesis and physiological function of blueberry leaves under low temperature stress (4–6°C) by exogenous hydrogen sulfide (H2S) by spraying leaves with 0.5 mmol•L-1 NaHS (H2S donor) and 200 μmol•L-1 hypotaurine (HT, H2S scavenger). The results showed that chlorophyll and carotenoid content in blueberry leaves decreased under low temperature stress, and the photochemical activities of photosystem II (PSII) and photosystem I (PSI) were also inhibited. The electron transfer process from QA to QB on the PSII acceptor side was sensitive to low temperature. Low temperature stress can reduce photosynthetic carbon assimilation capacity by inhibiting stomatal conductance (Gs) of blueberry leaves, and non-stomatal factors also play a limiting role at the 5th day of low temperature stress. Low temperature stress leads to the accumulation of Pro and H2O2 in blueberry leaves and increases membrane peroxidation. Spraying leaves with NaHS, a donor of exogenous H2S, could alleviate the degradation of chlorophyll and carotenoids in blueberry leaves caused by low temperature and reduce the photoinhibition of PSII and PSI. The main reason for the enhancement of photochemical activity of PSII was that exogenous H2S promoted the electron transfer from QA to QB on PSII acceptor side of blueberry leaves under low temperature stress. Exogenous H2S increased Gs and carboxylation efficiency (CE) of blueberry leaves under low temperature stress, thus ensuring normal photosynthesis. In addition, it promoted the accumulation of osmotic regulator proline under low temperature stress and significantly alleviated membrane peroxidation in blueberry leaves. Exogenous NaHS also induced a slight increase in H2O2 content under low temperature stress, which may be an important secondary signaling molecule in low temperature response of blueberry leaves regulated by exogenous H2S. H2S scavengers (HT) aggravated photoinhibition and the degree of oxidative damage under low temperature stress. Improving photosynthetic capacity as well as alleviating photosynthetic inhibition and oxidative stress with exogenous H2S is possible in blueberry seedlings under low temperature stress.

OBJECTIVES The aim was to evaluate the short-term outcomes of hybrid type II arch repair (HAR) and total arch replacement with frozen elephant trunk (TAR with FET) for acute DeBakey type I aortic dissection patients. METHODS From January 2017 to June 2019, the clinical data of acute DeBakey type I aortic dissection patients in a single centre were retrospectively reviewed; there were 92 cases of HAR and 268 cases of TAR with FET, with 56 pairs by propensity score matching. RESULTS After matching, the composite end points including 30-day mortality, stroke, paraplegia, renal failure, hepatic failure, reintubation or tracheotomy and low cardiac output syndrome were comparable (21.4%, 12/56 in the HAR group vs 21.4%, 12/56 in the TAR with FET group, P = 1.000). The rate of acute kidney injury (AKI) was significantly lower in the HAR group (58.9%, 33/56 vs 80.4%, 45/56, P = 0.031). The distribution of AKI stage according to the Kidney Disease Improving Global Outcomes criteria was different (P = 0.039), with more patients suffering from high-grade AKI in the TAR with FET group. Multivariable logistic analysis showed that the procedure type (HAR or TAR with FET) was not an independent predictor of composite adverse events or stroke. HAR was identified as a protective factor against AKI (odds ratio 0.485, 95% confidence interval 0.287–0.822; P = 0.007). CONCLUSIONS In the treatment of acute DeBakey type I aortic dissection, no significant differences were found in early outcomes between the 2 groups, but HAR was associated with a significantly lower incidence of AKI.

OBJECTIVE We aimed to evaluate the incidence of organ cysts in patients with type A aortic dissection (TAAD) to assess the association between organ cysts and TAAD. METHODS Between January 2018 and December 2018, all patients with TAAD undergoing aortic surgery at our center were enrolled into the study; patients undergoing isolated coronary artery bypass grafting at our center were selected as the control group. Baseline differences between the 2 groups were adjusted using propensity-score matching. The incidence of organ cysts was compared between the 2 groups in total and matched cohorts. RESULTS We enrolled 290 patients with TAAD and 293 patients with coronary artery disease (control group). The incidence of all organ cysts, liver cysts, renal cysts, and other organ cysts, was significantly higher in the TAAD group than in the control group (50.0% vs. 35.5%, p

OBJECTIVES The aim of this study is to evaluate the safety and efficacy of thoraco-abdominal aortic aneurysm repair with normothermic iliac perfusion. METHODS One hundred and ninety patients who underwent aortic replacement for the Crawford type II thoraco-abdominal aortic aneurysm between January 2005 and June 2017 were assigned to 2 groups: normothermic iliac perfusion (group A, n = 75) and deep hypothermic circulatory arrest (group B, n = 115). We selected 58 pairs of patients for propensity score matching. We analysed early operative death, a composite of complications and mid-term survival. RESULTS After propensity score matching, no early operative death occurred in group A (0.0%), and group B had 4 cases of early operative death (6.9%), with a statistically significant difference (P = 0.047). The composite of complications was reported in 11 patients in group A (21.0%) and in 21 patients in group B (36.2%) (P = 0.038). Age >50 years [odds ratio (OR) 6.50, 95% confidence interval (CI) 2.32-16.36; P = 0.020], deep hypothermia (OR 12.13, 95% CI 1.64-23.13; P = 0.003) and chronic renal insufficiency (OR 8.21, 95% CI 2.34-43.33; P < 0.001) were independent risk factors for early operative death. The 3-year, 5-year and 7-year survival rates were 98.3%, 98.3% and 86.9% in group A and 86.9%, 86.9% and 86.9% in group B, respectively (P = 0.471). The 7-year cumulative incidence function rates for reintervention were 0.026% in group A and 0.048% in group B (P = 0.625). CONCLUSIONS Normothermic iliac perfusion provides a viable alternative for thoraco-abdominal aortic aneurysm repair, which reduced early operative death and composited complications.

Lithium–sulfur batteries have become one of the most promising high-energy batteries owing to their high energy density and low cost. Nevertheless, one of the major problems is the infamous shuttle effect of polysulfides, which causes active material sulfur loss and low Coulombic efficiency. Here, we designed a 3-D configuration electrodes. Multi-walled carbon nanotubes paper (MWCNTsP) was used as the current collector, and MWCNTs film was used as the interlayer (MWCNTsI) between the positive electrode and the separator. The unique configuration retarded the dissolution and dispersion of polysulfides. The electrochemical tests showed that the initial discharge capacity reached 1352 mAh/g and the Coulombic efficiency reached around 100% with the 3-D configuration electrode (MWCNTsP–S@MWCNTsI). The discharge capacity remained 1028 mAh/g after 20 cycles. Additionally, the batteries maintained a specific capacity of 902 mAh/g, 782 mAh/g and 509 mAh/g at the current rate of 1 C, 2 C and 5 C, respectively.

As compared to permanent orthopedic implants for load-bearing applications, biodegradable orthopedic implants have the advantage of no need for removing after healing, but they suffer from the “trilemma” problem of compromising among sufficiently high mechanical properties, good biocompatibility and proper degradation rate conforming to the growth rate of new bones. In the present work, in vitro and in vivo studies of a Zn-0.05wt%Mg alloy (namely, Zn-0.05Mg alloy) were conducted with pure Zn as a control. The Zn-0.05Mg alloy is composed of a small amount of Mg2Zn11 phase embedded in the refined Zn matrix with an average grain size of ∼20 μm. The addition of 0.05 wt% Mg into Zn significantly increases the ultimate tensile strength up to 225 MPa and the elongation to fracture to 26%, but has little influence on the in vitro degradation rate. Both Zn and Zn-0.05Mg alloy exhibit homogeneous in vitro degradation with a rate of about 0.15 mm/year. Based on the cytotoxicity evaluation, Zn and Zn-0.05Mg alloy do not induce toxicity to L-929 cells, indicating that they have little toxicity to the general functions of the animal. An in vivo biocompatibility study of Zn and Zn-0.05Mg alloy samples by placing them in a rabbit model for 4, 12 and 24 weeks, respectively did not show any inflammatory cells, and demonstrated that new bone tissue formed at the bone/implant interface, suggesting that Zn and Zn-0.05Mg alloy promote the formation of new bone tissue. The in vivo degradation of Zn and Zn-0.05Mg alloy does not bring harm to the important organs and their cell structures. More interestingly, Zn and Zn-0.05Mg alloy exhibit strong antibacterial activity against Escherichia coli and Staphylococcus aureus. The above results clearly demonstrate that the Zn-0.05Mg alloy could be a potential biodegradable orthopedic implant material.

The boundary element method (BEM) and sequential function specification method (SFSM) are used to research the inverse problem of boundary heat flux identification in the two-dimensional heat conduction system. The future time step in the SFSM is optimized by introducing the residual error principles to get the more accurate inversion results. For the forward problems, the BEM is used to calculate the required temperature value of discrete point; for the inverse problems, the impacts of different future time steps, measuring point position, and measuring error on the inversion results are discussed. Furthermore, the comparison is made for the optimal future time step obtained by introducing the residual error principle and the inherent future time step. The example analysis shows that the method proposed still has higher accuracy when the measuring error exists or the measuring point position is far away from the boundary heat flux.

A 3-dimensional carbonized multi-walled carbon nanotube (MWCNT) paper was used as the host of nano-tin oxide (SnO2) for lithium-ion batteries (LIBs). The cellulose fibers were fully mixed with MWCNTs in water. Then, the paper was obtained via vacuum filtration. Carbonization was carried out in a vacuum furnace at 1460°C. SnO2 slurry was coated on the carbonized MWCNT paper (CMP). Scanning electron microscopy (SEM) was utilized to observe the anode electrode. The images of SEM indicated that the nano-SnO2 was embedded into the holes of the porous CMP collector. This contributed the increase of contact interface area of the nano-SnO2 and the collector and the significantly reduced interface resistance. Electrochemical tests showed that the initial discharge capacity reached 1745 mAh g−1 with a coulumbic efficiency (CE) of 70.39% at a current density of 50 mA g−1. The composite electrode still maintained a reversible capacity of 753 mAh g−1 with a CE of 98% at a current density of 200 mA g−1 after 100 cycles. These marvelous composite electrodes exhibited a promising future for the next generation of LIBs.

Determination of backfill strength and composition are key to the use of staged open stope mining with subsequent filling. The traditional method of determining backfill strength has certain disadvantages, so it is necessary to explore a more scientific approach to obtain reasonable matches between backfill strength and excavated rock mass. Stress-strain curves of backfills with different cement-tailings ratios were obtained from laboratory mechanical tests for Zhongguan Iron Mine. Damage constitutive models prior to peak stress were established from damage mechanics. Using the principle that peak deformation energy corresponds to the energy released from an excavated rock mass, the optimum backfill strength and composition ratio were determined. The study provides a scientific basis for the backfilling design of this mine.

Based on the boundary element method and the decentralized fuzzy inference algorithm, the thermal conductivity in the two-dimensional unsteady-state heat transfer system changing with the temperature is deduced. The more accurate inversion results are obtained by introducing the variable universe method. The concrete method is as follows: using experimental means to obtain the instantaneous temperature in the material or on the boundary, to determine the thermal conductivity of the material by solving the inversion problem. The boundary element method is used to calculate the regional boundary and internal temperature in the direct problem. With the inversion problem, the decentralized fuzzy inference algorithm is used to compensate for the initial guess of the thermal conductivity by using the difference between the temperature measurement and the temperature calculation. In the inversion problem, the influence of the initial guess of different thermal conductivities, different numbers of measuring points, and the existence of measurement errors on the results is discussed. The example calculation and analysis prove that, with different initial guesses, existence of measurement errors, and the number of boundary measurements decrease, the methods adopted in this paper still maintain good validity and accuracy.

To solve the problem of low early strength of the CaO-activated slag system, the influence of adding Al2(SO4)3 as an auxiliary activator on the compressive strength development, hydration products and microstructure of CaO-activated blast furnace slag (BFS) system was investigated in this study. The results showed that adding Al2(SO4)3 enhanced the strength of binders prepared from two slag types (S1 and S2) when the addition of Al2(SO4)3 was no more than 3 wt%, including 3-d strength and 28-d strength; with an increase in Al2(SO4)3 content, the strength enhancement gradually weakened. The strength enhancement of Al2(SO4)3 was attributed to its ability to accelerate the hydration reaction and induce more dissolution of BFS as well as the formation of more ettringite and calcium silicate hydrate gels, which was confirmed by the setting time, hydration heat, X-ray powder diffraction, thermogravimetric analysis and mercury intrusion porosimeter. This study proved that the compressive strength enhancement effect of Al2(SO4)3 on group 1 was weaker than on group 2 due to the difference in chemical oxide composition and the reactivity of the two slag types. Further, the addition of Al2(SO4)3 significantly influenced the pore size distribution of the binders.

Oil shale residue (OSR), a ubiquitous by-product of crude oil processing, is usually stacked on the surface and will pollute the environment. In this study thermal activation technology was used to increase the pozzolanic reactivity of OSR, which was used as supplementary cementitious materials (SCM). Different calcination temperature (500, 600 and 700℃) was carried out to discussed the transformation of mineralogy of OSR, after which, the pozzolanic reactivity test was carried out and the hydration products of OSR were analyzed. Finally, the OPC was replaced with OSRs varied from 10% to 50% by weight to analyze the fresh and mechanical behavior of the samples. The results showed that a number of potentially activatable clay minerals content in the OSR such as kaolinite, montmorillonite and illite, calcining OSR at 500–700℃ can improve pozzolanic reactivity and the optimal calcination temperature is about 600℃. The compressive strength of OSR/OPC composites material increased by around 8% (curing for 3 d) and 11% (curing for 28 d) using OSR (calcined at 600℃ and replacement rate at 10%) as SCMs.

It is a trend that the crack detection method of ballastless track slab changes from manual detection to high-speed vehicle detection. A crack detection method based on an infrared thermometer is presented in this paper. The basic principle of this method is introduced. This method is based on the fact that cracks cannot fill the field of view of an infrared thermometer. So the signal of the infrared thermometer is a mixture of cracks and track slabs. And it is separated by the angle coefficient in this paper. Simulations are carried out to study the influence factors of the detecting lower limit of crack width. And experiments are carried out to verify the correctness of the crack detection principle. The crack detection method can be used as a supplement to image processing to reduce the probability of missing detection.

Minimally invasive surgical operation of intramedullary (IM) nailing is a standard technique for treating diaphyseal fractures. However, in addition to its advantages, there are some drawbacks such as the frequent occurrence of malalignment, physical fatigue and high radiation exposure to medical staff. The use of robotic and navigation techniques is promising treatments for femoral fractures.This paper presents a novel robot-assisted manipulator for femoral shaft fracture reduction with indirect contact with the femur. An alternative clinical testing model was proposed for orthopedic surgeons to practice femoral fracture reduction. This model imitates the human musculoskeletal system in shape and functional performance. The rubber tube simulate muscles providing contraction forces, and the silicone simulates passive elasticity of muscles. Two-group experiments were performed for studying feasibility of the teleoperated manipulator.The average operative time was about 7min. In the first group experiments, the femur axial, antero-posterior (AP) and lateral views mean errors were 2.2mm, 0.7mm and 1.1mm, respectively, and their maximums were 3.0mm, 0.9mm and 1.5mm; the mean errors of rotation were 0.8° around x-axis, 1.6° around y-axis, 2.0° around z-axis, and their maximums were 1.1°, 2.2°, 2.9°, respectively. For the second group experiments, the femur axial, AP and lateral views mean errors were 1.8mm, 0.4mm and 0.8mm, respectively, and their maximums were 2.2mm, 0.7mm and 1.1mm; the mean errors of rotation were 1.2° around x-axis, 1.6° around y-axis, 1.9° around z-axis, and their maximums were 2.4°, 1.8°, 2.7°, respectively. Reduction for AP view displacement is easier than lateral (p0.05) because of the tube-shaped anatomy and the muscle contraction forces. Errors around x-axis are smaller than those around y-, and z- axes (p0.05), i.e., electro-mechanical actuator is easier to control than pneumatic.An experimental model for simulating human femoral characteristics was proposed. Experiments conducted on the artificial lower limb model demonstrated high reduction accuracy, safety, sufficient working space, and low radiation exposure of the proposed robot-assisted system. Thus, the minimally invasive teleoperated manipulator would have greater development prospect.

Multiwalled carbon nanotubes have been synthesized by floating reactant method in a vertical tubular reactor. An internal short approach process was developed to achieve the pre-lithiated multiwalled carbon nanotube MWCNTs/graphite composite anodes. Lithium-ion capacitors (LICs) were composed of a pre-lithiated multiwalled carbon nanotubes/graphite composite anode and an activated carbon (AC) cathode. The electrochemical performance of LICs with different MWCNTs content was investigated through galvanostatic charge/discharge and electrochemical impedance. The results show that the charge–discharge performance of LICs was greatly improved with the addition of MWCNTs in anodes. LIC25 (25 wt% MWCNTs) was found to achieve the optimal electrochemical performance. The LIC25 hold a specific capacitance of 58.2 F/g at the current density of 100 mA/g. The maximum energy density and power density were up to 96 Wh/kg and 10.1 kW/kg, respectively, in the current range of 100~8000 mA/g. The continuous galvanostatic charge–discharge cycling tests revealed that the LIC25 maintained excellent capacity retention of 86% after 3000 cycles.

This paper describes the development of a novel multi-target multispectral pyrometer to remotely measure the true temperature of the plume of a solid fuel rocket engine in a harsh environment ground test. Using an optical fiber transmission technique, the core part of the instrument can be located 100 m away from the test site, so the influence of the harsh environment can be reduced and the instrument reliability improved. Optics are separated from prisms to accurately locate targets. Based on preamplifier circuits and parallelly adjacent pixels of the photodiode detectors, the measurement lower limit can reach 900 °C. The pyrometer is validated against experimental data from field measurements of a solid fuel rocket motor plume. The results demonstrate that the true temperature of the solid fuel rocket engine plume can be acceptably measured with the proposed pyrometer.

The compound variable inverse problem which comprises boundary temperature distribution and surface convective heat conduction coefficient of two-dimensional steady heat transfer system with inner heat source is studied in this paper applying the conjugate gradient method. The introduction of complex variable to solve the gradient matrix of the objective function obtains more precise inversion results. This paper applies boundary element method to solve the temperature calculation of discrete points in forward problems. The factors of measuring error and the number of measuring points zero error which impact the measurement result are discussed and compared with L-MM method in inverse problems. Instance calculation and analysis prove that the method applied in this paper still has good effectiveness and accuracy even if measurement error exists and the boundary measurement points’ number is reduced. The comparison indicates that the influence of error on the inversion solution can be minimized effectively using this method.

The total aortic arch replacement with frozen elephant trunk is increasingly being used. However, deep hypothermic circulatory arrest is inevitable. We performed a novel surgical technique, the ‘aortic balloon occlusion’, in the surgical treatment of Stanford type A aortic dissection to reduce the adverse effects caused by deep hypothermic circulatory arrest.

Sulfur is widely distributed in earth and is low cost and environmentally friendly. Lithium-sulfur battery was considered to be the next generation of new energy storage systems. However, the solubility, deposition, and shuttle effect of polysulfides of lithium-sulfur (Li-S) batteries checked the practical applications owing to low coulomb efficiency and the loss of active substances. Tris (2-carboxyethyl) phosphine (TCEP) can be used as a shear agent to transfer higher order lithium-polysulfide compounds (Li2Sx, x > 6) into low-order lithium-polysulfide compounds (Li2Sx, x < 4). The dissolution and diffusion of polysulfides were checked with an increase of utilization rate of active substances. The performance of charge and discharge and cycle of lithium-sulfur battery also were improved. Multi-walled carbon nanotubes (MWCNTs) provided high conductivity and maintained structural integrity of electrode, the diameter of MWCNTs is about 80 nm, and length is about 15 μm. The electrochemical test results showed that the first discharge capacity of electrode with TCEP interlayer reached 1410 mAh/g at a rate of 0.05 C, and the utilization rate of active material was as high as 84.6%. After 10 cycles at 3 C ratio, the discharge specific capacity still reached 526 mAh/g and the coulomb efficiency remained at 90.6%. It showed good rate and cycling performance.

Blast furnace slag was used as the main raw material to prepare the alkali activated slag (AAS), a low-carbon binder, for cemented paste backfill (CPB). The optimum parameters for preparing the AAS binders using an orthogonal experiment were obtained. Under the optimum conditions (NaOH content was 3 wt. %, Ordinary Portland cement (OPC) content was 7 wt. %, and gypsum dosage was 4 wt. %), the 28 days compressive strength of the binder was 29.55 MPa. The flow ability of the fresh CPB slurry decreased with solid content due to the increased yield stress, while the flow ability increased when rising the binder dosage. A predictive model for the compressive strength of CPB samples was reached through multivariate analysis and the R2 values were higher than 0.9. Sensitivity analysis showed that the solid content is the most important parameter which influences on the development of the CPB strength with a correlation coefficient of 0.826. From the Toxicity Characteristic Leaching Procedure (TCLP) tests, the leaching concentrations of Pb and Cd were below the threshold. As a result, the AAS has potential application as an alternative binder and cemented paste backfill.

OBJECTIVES The aim of this study was to propose and evaluate the new operative technique of aortic balloon occlusion in total aortic arch replacement (TAR) with the frozen elephant trunk that can significantly decrease the time of circulatory arrest and increase the hypothermic cardiopulmonary bypass (CPB) temperature. METHODS Between 2010 and 2018, 1335 patients with aortic dissection who underwent TAR with the frozen elephant trunk were included in the study. The newest 80 cases were treated with aortic balloon occlusion. To illustrate the difference with the new procedure, 1255 conventional TAR cases served as the historical control. Femoral and right axillary artery cannulations were used for CPB and antegrade selective cerebral perfusion. Circulatory arrest was implemented at the nasopharyngeal temperature of 28°C with continuous antegrade selective cerebral perfusion. After the stent graft was inserted into the true lumen of the descending aorta, the aortic balloon in a sheath was deployed into the stent graft and positioned at the metal part of the stent graft. When the balloon was inflated with enough saline to compress the stent graft, the sheath was simultaneously pressed by hand to properly fix the balloon and avoid displacement. Then femoral perfusion could be resumed. RESULTS The aortic balloon occlusion technique was successful in all patients, with the median duration of circulatory arrest being 5 (interquartile range 3–7) min. The 30-day mortality rate was 6.25% (5/80), whereas with the conventional method it was 9.40% (118/1255). The postoperative conscious revival (8.67 vs 11.40 h, P CONCLUSIONS The aortic balloon occlusion technique is a feasible way to shorten circulatory arrest significantly, to obviate the need for deep hypothermia in TAR with the frozen elephant trunk and to provide favourable protective effects on the central nervous, haematological and visceral systems. With these satisfactory results, this technique deserves further investigation.

OBJECTIVES Our goal was to review the surgical treatment of retrograde type A aortic dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) in our centre. METHODS From January 2014 to April 2018, 22 patients with RTAD after TEVAR were operated on in our centre. The mean age at operation was 52.0 ± 8.0 years old. The median interval between the primary TEVAR procedure and RTAD was 4.6 months (range 0–120 months). The postoperative mortality and morbidity rates were calculated to evaluate the early and long-term results. RESULTS Twenty patients received total arch replacement with the frozen elephant trunk technique and 2 patients received total arch replacement alone. The mean cardiopulmonary bypass time, aortic cross-clamp time and selective cerebral perfusion time were 172.4 ± 39.3, 100.1 ± 30.3 and 19.7 ± 10.5 min, respectively. The incidence of major adverse events was 18.6% (4/22), including stroke in 1 patient, myocardial dysfunction in 1 patient and renal failure necessitating dialysis in 3 patients. Death within 30 days was 13.6% (3/22 patients). The follow-up data were available for all 19 survivors. The mean follow-up period was 32.2 ± 16.2 months (range 10–62 months). No deaths or aortic-related events occurred during the follow-up period. CONCLUSIONS Total arch replacement with or without the frozen elephant trunk technique was suitable for the management of RTAD after TEVAR, with acceptable early and long-term results.