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Measurement error is non-negligible and crucial in SHM data analysis. In many applications of SHM, measurement errors are statistically correlated in space and/or in time for data from sensor networks. Existing works solely consider spatial correlation for measurement error. When both spatial and temporal correlation are considered simultaneously, the existing works collapse, as they do not possess a suitable form describing spatially and temporally correlated measurement error. In order to tackle this burden, this paper generalizes the form of correlated measurement error from spatial correlation only or temporal correlation only to spatial-temporal correlation. A new form of spatial-temporal correlation and the corresponding likelihood function are proposed, and multiple candidate model classes for the measurement error are constructed, including no correlation, spatial correlation, temporal correlation, and the proposed spatial-temporal correlation. Bayesian system identification is conducted to achieve not only the posterior probability density function (PDF) for the model parameters, but also the posterior probability of each candidate model class for selecting the most suitable/plausible model class for the measurement error. Examples are presented with applications to model updating and modal frequency prediction under varying environmental conditions, ensuring the necessity of considering correlated measurement error and the capability of the proposed Bayesian system identification in the uncertainty quantification at the parameter and model levels.

In this work, a rapid and controllable ultrasonic vibration method for forming Al-based metallic glass at room temperature is proposed. This method can dramatically improve the forming ability of Al-based metallic glasses, which are virtually brittle at room temperature and have almost no supercooled liquid region at high temperatures. Under ultrasonic vibration, Al-based metallic glasses exhibited obvious plastic flow, with a maximum deformation degree up to 58% and an average deformation degree up to 43%. It is worth mentioning that no crystalline peaks were found on the X-ray diffraction patterns after deformation under ultrasonic vibration, and the mechanical properties remained the same as the primary sample. The present results provide a new approach for the deformation and forming of Al-based metallic glasses, which can significantly broaden their applications.

BackgroundIn this study, we designed a new (Su’S) target area delineation to protect the normal liver during liver regeneration and prospectively evaluate liver regeneration after radiotherapy, as well as to explore the clinical factors of liver regeneration and established a model and nomogram.MethodsThirty patients treated with preoperative downstaging radiotherapy were prospectively included in the training cohort, and 21 patients treated with postoperative adjuvant radiotherapy were included in the validation cohort. The cut-off points of each optimal predictor were obtained using receiver-operating characteristic analysis. A model and nomogram for liver regeneration after radiotherapy were developed and validated.ResultsAfter radiotherapy, 12 (40%) and 13 (61.9%) patients in the training and validation cohorts experienced liver regeneration, respectively. The risk stratification model based on the cutoffs of standard residual liver volume spared from at least 20 Gy (SVs20 = 303.4 mL/m2) and alanine aminotransferase (ALT=43 u/L) was able to effectively discriminate the probability of liver regeneration. The model and nomogram of liver regeneration based on SVs20 and ALT showed good prediction performance (AUC=0.759) in the training cohort and performed well (AUC=0.808) in the validation cohort.ConclusionsSVs20 and ALT were optimal predictors of liver regeneration. This model may be beneficial to the constraints of the normal liver outside the radiotherapy-targeted areas.

A hybrid process combining ultrasonic injection molding and electrical discharge machining was proposed to realize the economic, high-precision, and environmental-friendliness production of glass fiber reinforced polypropylene microstructured parts. First, the prism array microstructures were processed on tungsten carbide-cobalt (WC-8 wt% Co) substrate by low-speed wire electrical discharge machining and used as the mold core. Then, the glass fiber reinforced polypropylene composite (GF/PP) was melted under ultrasonic vibration, and the surface microstructure of the mold core was replicated. The experimental results show that this method can efficiently and accurately manufacture microstructured parts, and the microstructure has a high replication rate up to 95.5%. By replicating the microstructure, the surface contact angle of GF/PP parts increased from 57.1° to 134.9°, and the wettability changed from hydrophilicity to hydrophobicity. The mechanical properties test results show that the GF/PP parts fabricated by ultrasonic injection molding had excellent mechanical properties, and the 30% GF/PP parts show the highest tensile strength of 56.9 MPa. This work provides a new option for fabricating fiber reinforced composite parts.

In the present work, PH13-8Mo stainless steel parts without yttrium and with yttrium (Y) were manufactured by selective laser melting (SLM). The microstructure, phase composition and grain orientation of the stainless steels parts with Y and without Y were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), electron-backscatter diffraction (EBSD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The characterization results revealed that the addition of Y clearly refined the grain size of the PH13-8Mo steel formed part, resulting in more equiaxed massive grains and in a less anisotropic microstructure. PH13-8Mo stainless steel formed parts were mainly composed of martensite and retained austenite. The addition of Y could significantly increase the content of retained austenite and also generate nano-sized precipitates containing Y. The mechanical test results showed that both strength and toughness of the shaped parts containing Y were improved synergistically. The yield strength reached 1443 MPa, the elongation was 12.2%, and the room temperature impact energy reached 124.25 J/cm2. The strengthening and toughening by Y of the formed parts were mainly attributed to grain refinement, higher volume fraction of the retained austenite and the formation of nano-sized precipitates containing Y.

Intrauterine growth restriction (IUGR) pigs are characterized by long-term growth failure, metabolic disorders, and intestinal microbiota imbalance. The characteristics of the negative effects of IUGR at different growth stages of pigs are still unclear. Therefore, this study explored through multi-omics analyses whether the IUGR damages the intestinal barrier function and alters the colonization and metabolic profiles of the colonic microbiota in growing-finishing pigs. Seventy-two piglets (36 IUGR and 36 NBW) were allocated for this trial to analyze physiological and plasma biochemical parameters, as well as oxidative damage and inflammatory response in the colon. Moreover, the colonic microbiota communities and metabolome were examined using 16s rRNA sequencing and metabolomics technologies to reveal the intestinal characteristics of IUGR pigs at different growth stages (25, 50, and 100 kg). IUGR altered the concentrations of plasma glucose, total protein, triglycerides, and cholesterol. Colonic tight junction proteins were markedly inhibited by IUGR. IUGR decreased plasma T-AOC, SOD, and GSH levels and colonic SOD-1, SOD-2, and GPX-4 expressions by restraining the Nrf2/Keap1 signaling pathway. Moreover, IUGR increased colonic IL-1β and TNF-α levels while reducing IL-10, possibly through activating the TLR4-NF-κB/ERK pathway. Notably, IUGR pigs had lower colonic Streptococcus abundance and Firmicutes-to-Bacteroidetes ratio at the 25 kg BW stage while having higher Firmicutes abundance at the 100 kg BW stage; moreover, IUGR pigs had lower SCFA concentrations. Metabolomics analysis showed that IUGR increased colonic lipids and lipid-like molecules, organic acids and derivatives, and organoheterocyclic compounds concentrations and enriched three differential metabolic pathways, including linoleic acid, sphingolipid, and purine metabolisms throughout the trial. Collectively, IUGR altered the nutrient metabolism, redox status, and colonic microbiota community and metabolite profiles of pigs and continued to disrupt colonic barrier function by reducing antioxidant capacity via the Nrf2/Keap1 pathway and activating inflammation via the TLR4-NF-κB/ERK pathway during the growing-finishing stage. Moreover, colonic Firmicutes and Streptococcus could be potential regulatory targets for modulating the metabolism and health of IUGR pigs. [ABSTRACT FROM AUTHOR]

Background: Pulsed field ablation (PFA) has emerged as a novel non‐thermal modality with highly myocardium‐specific. However, the PFA catheter based on contact force (CF)‐sensing has not been reported. The study aimed to evaluate the efficacy and safety of a novel CF‐sensing PFA catheter. Methods: First, different CF (5, 15, 25, and 35 g) of the novel PFA catheter were evaluated on lesion dimensions during ablation on right and left ventricle in two pigs. Next, this catheter was further evaluated on four typical sites of superior vena cava (SVC), cavotricuspid isthmus (CTI), right superior pulmonary vein (RSPV), and right inferior pulmonary vein (RIPV) for atrial ablation in another six pigs. Electrical isolation was evaluated immediately after ablation and 30‐day survival. Chronic lesions were assessed via histopathology after euthanasia. Acute and chronic safety outcomes were observed peri‐ and post‐procedurally. Results: In ventricular ablation, increased CF from 5 to 15 g produced significantly greater lesion depth but nonsignificant increases from 15 to 35 g. In atrial ablation, the novel CF‐sensing PFA deliveries produced an acute attenuation of local electrograms and formation of a continuous line of block in all 6 pigs. The ablation line remained sustained blockage at the 30‐day survival period. The CF of SVC, CTI, RSPV, and RIPV was 9.4 ± 1.5, 14.5 ± 3.2, 17.2 ± 2.6, and 13.4 ± 2.8 g, respectively. Moreover, no evidence of damage to esophagus or phrenic nerve was observed. Conclusion: The novel CF‐sensing PFA catheter potentiated efficient, safe, and durable ablation, without causing damage to the esophagus or phrenic nerve. [ABSTRACT FROM AUTHOR]

Abstract Background Child-Turcotte-Pugh (CTP) score extensively used to assess hepatic function, predicting postoperative outcome of hepatocellular carcinoma (HCC) patients. Lately, the albumin–bilirubin (ALBI) grade has been identified to be a predictor of overall survival of HCC patients. In this investigation, we compared the pre-SBRT ALBI and CTP scores with the prognosis of patients with HCC. Methods This cohort study included 594 HCC patients who treated with SBRT. Overall survival (OS) rates were measured from treatment date to death date or last follow-up. We compared ALBI score with the CTP score in predicting long-term survival. Results The average follow-up time was 21 months (1 to 82 months). The CTP and ALBI ratings have discriminatory for long-term survival across the groups. CTP class was significantly related to OS, with a median OS of 29.9 months in CTP-A, 11.5 in CTP-B (P 0.05). Conclusions To assess liver dysfunction in HCC patients before SBRT, traditional CTP classification is a necessary but imperfect tool for assessing HCC liver injury. The ALBI score is a more objective, discriminatory and evidence-based approach in CTP-A groups, and need to be validated in CTP ≥ B7 class.

Kai Xin San (KXS, containing ginseng, hoelen, polygala, and acorus), a traditional Chinese herbal compound, has been found to regulate cognitive dysfunction; however, its mechanism of action is still unclear. In this study, 72 specific-pathogen-free male Kunming mice aged 8 weeks were randomly divided into a vehicle control group, scopolamine group, low-dose KXS group, moderate-dose KXS group, high-dose KXS group, and positive control group. Except for the vehicle control group and scopolamine groups (which received physiological saline), the doses of KXS (0.7, 1.4 and 2.8 g/kg per day) and donepezil (3 mg/kg per day) were gastrointestinally administered once daily for 2 weeks. On day 8 after intragastric treatment, the behavioral tests were carried out. Scopolamine group and intervention groups received scopolamine 3 mg/kg per day through intraperitoneal injection. The effects of KXS on spatial learning and memory, pathological changes of brain tissue, expression of apoptosis factors, oxidative stress injury factors, synapse-associated protein, and cholinergic neurotransmitter were measured. The results confirmed the following. (1) KXS shortened the escape latency and increased residence time in the target quadrant and the number of platform crossings in the Morris water maze. (2) KXS increased the percentage of alternations between the labyrinth arms in the mice of KXS groups in the Y-maze. (3) Nissl and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining revealed that KXS promoted the production of Nissl bodies and inhibited the formation of apoptotic bodies. (4) Western blot assay showed that KXS up-regulated the expression of anti-apoptotic protein Bcl-2 and inhibited the expression of pro-apoptotic protein Bax. KXS up-regulated the expression of postsynaptic density 95, synaptophysin, and brain-derived neurotrophic factor in the cerebral cortex and hippocampus. (5) KXS increased the level and activity of choline acetyltransferase, acetylcholine, superoxide dismutase, and glutathione peroxidase, and reduced the level and activity of acetyl cholinesterase, reactive oxygen species, and malondialdehyde through acting on the cholinergic system and reducing oxidative stress damage. These results indicate that KXS plays a neuroprotective role and improves cognitive function through reducing apoptosis and oxidative stress, and regulating synapse-associated protein and cholinergic neurotransmitters.

Despite the excellent properties, amorphous alloys find limited applications and to find plastic forming ability has been a longstanding problem. In this work, an effective ultrasonic assisted micro-shear punching (UMSP) method is proposed for amorphous alloys. By applying ultrasonic vibration and molten plastics viscous medium, a series of shapes and products with micro-length scale to macro-length scale can be successfully fabricated in 50 ms. Different from traditional crystalline alloys, the amorphous alloys become soft at certain regions during the ultrasonic hammering owing to the unique disordered structures, thereby resulting in the low-stress forming approach.

Background: Macroscopic vascular invasion (MVI) is a terminal manifestation of hepatocellular carcinoma (HCC) and carries an extremely poor prognosis. In Chinese and Korean HCC guidelines, transarterial chemoembolization (TACE), or/and radiotherapy (RT) is adopted for treatment of MVI. In the current study, we aimed to compare the long-term outcome of TACE + RT to that of RT alone in patients with local advanced HCC with MVI.Methods: In this retrospective study, 148 treatment-naive patients of HCC with MVI were enrolled. Of the patients enrolled, 49 received TACE + RT treatment, whereas 99 patients received RT alone as a monotherapy. Overall survival (OS), progression-free survival (PFS), and intrahepatic control were evaluated using univariable and propensity score–matched analyses.Results: During follow-up, 126 patients (85.1%) died. The median follow-up time was 55.0 months in the RT group and 57.0 months in the TACE + RT group. The TACE + RT group showed better OS and PFS than the RT group, but intrahepatic control was comparable in these two groups. Of 41 cases well-pairs after propensity score matching, the associations between TACE + RT and better OS and PFS remained (15.0 vs. 8.0 months, and 8.0 vs. 4.0 months, all P < 0.05). The 1-, 2-, 3-, and 5-years OS rates in the TACE + RT group were 56.1, 28.6, 20.8, and 15.7 vs. 31.5%, 13.1%, 9.8%, and 6.7% in the RT group, respectively (P = 0.017). The 6-, 12-, and 24-months rates in the TACE + RT group were 51.2, 39.0, and 23.1% vs. 36.6%, 13.9%, and 11.1% in the RT group, respectively (P = 0.04). Two patients (4.1%) experienced radiation-induced liver disease (RILD), and one (2.0%) experienced RT-related gastrointestinal (GI) bleed in the TACE + RT groups. Nine patients (9.1%) experienced RILD, and two (2.0%) experienced RT-related GI bleed in the RT groups.Conclusion: Transarterial chemoembolization + RT had well-complementarity with no more complications than RT alone, providing a better PFS and OS compared with RT-alone treatment for HCC with MVI.

Background and Objective: It is unclear if stereotactic body radiation therapy (SBRT) or transarterial chemoembolization (TACE) is better for the treatment of inoperable early-stage hepatocellular carcinoma (HCC). This study aimed to retrospectively compare the efficacy of SBRT to TACE in patients with inoperable Barcelona Clinic Liver Cancer (BCLC)-A stage HCC.Materials and Methods: In this multi-institutional retrospective study, a total of 326 patients with inoperable BCLC-A stage HCC were enrolled. Totally, 167 patients initially received SBRT and 159 initially received TACE. Overall survival (OS), local control (LC), intrahepatic control (IC), and progression-free survival (PFS) were evaluated in univariable and propensity-score matched analyses.Results: There was a smaller median tumor size in the SBRT group than in the TACE group (3.4 cm vs. 7.2 cm, P < 0.001). After propensity score matching in the selection of 95 patient pairs, SBRT had better LC, IC, and PFS than TACE but showed comparable OS. The accumulative 1-, 3-, and 5-year OS rates were 85.7, 65.1, and 62.8% in the SBRT group and 83.6, 61.0, and 50.4% in the TACE group, respectively (P = 0.29). The accumulative 1-, 3-, and 5-year PFS were 63.4, 35.9, and 27.5% in the SBRT group and 53.5, 27.4, and 14.2% in the TACE group, respectively (P = 0.049). The accumulative 1-, 3-, and 5-year LC were 86.8, 62.5, and 56.9% in the SBRT group and 69.3, 53.3, and 36.6% in the TACE group, respectively (P = 0.0047). The accumulative 1-, 3-, and 5-year IC were 77.3, 45.9, and 42.4% in the SBRT group and 57.3, 34.1, and 17.7% in the TACE group, respectively (P = 0.003). On multivariate analysis, treatment (SBRT vs. TACE) was a significant covariate associated with local and intrahepatic control (HR = 1.59; 95% CI: 1.03–2.47; P = 0.04; HR = 1.61; 95% CI: 1.13–2.29; P = 0.009).Conclusions: SBRT was an alternative to TACE for inoperable BCLC-A stage HCC with better local and intrahepatic control. Controlled clinical trials are recommended to evaluate the actual effects of this novel regimen adequately.

Background: Several epidemiological studies have been performed to evaluate the association of dietary intake of vitamin C-oriented foods (DIVCF) with risk of fracture and bone mineral density (BMD) loss, but the results remain controversial. Therefore, we conducted a systematic meta-analysis to assess this correlation.Methods: We searched EmBase, PubMed, Web of Science, and the Chinese database CNKI for relevant articles published up to August 2019. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using the random- or fixed-effects model. Discrepancies were resolved by consultation with a third expert.Results: A total of 13 eligible articles (including 17 studies) with 19,484 subjects were identified for the present meta-analysis. The pooled RR of hip fracture for the highest vs. lowest category was 0.66 (95% CI, 0.47–0.94) for DIVCF, i.e., people with a greater frequency of Vitamin C uptake had a 34% (95% CI, 6%−53%) lower prevalence of hip fracture. In subgroup analyses stratified by study design, gender, and age, the negative associations were statistically significant. Furthermore, the statistical analysis of the association between DIVCF and risk of osteoporosis (RR, 0.66; 95% CI, 0.48–0.92), BMD at the lumbar spine (pooled r, 0.15; 95% CI, 0.09–0.23), and BMD at the femoral neck (pooled r, 0.20; 95% CI, 0.11–0.34) showed beneficial effects of DIVCF.Conclusion: Our meta-analysis indicates that DIVCF is negatively associated with the risk of hip fracture, osteoporosis, and BMD loss, suggesting that DIVCF decreases the risk of hip fracture, osteoporosis, and BMD loss.

Mullite reticulated porous ceramics (RPC) are one of the key components for porous media burner, the mechanical properties of mullite RPC decided the service life of the burner. However, the irregularities of cellular structure made it difficult to reveal the fracture behavior of mullite RPCs. In this study, the three-dimensional (3-D) structures of mullite RPCs were analyzed by X-ray computed tomography. The strength and damage behavior of mullite RPCs were respectively investigated via the compression tests and finite element modeling based on the actual 3-D model, also the corresponding strengthening mechanism was proposed. The results indicated that the reconstructed 3-D model exhibited the real microstructure of mullite RPCs, containing the hollow struts and strut defects. The Young's modulus calculated from actual 3-D structures was lower than that from Gibson-Ashby theory. In addition, the surface defects preceded triangular tips to generate the area of stress concentration, leading to the fracture behavior first occurred at the strut defects. With the formation of dense strut in mullite RPCs, the stress uniformly distributed in the whole solid skeleton, thus significantly improving the damage resistance of mullite RPCs.