Synchronization bandwidth enhancement induced by a parametrically excited oscillator.

The synchronization phenomenon in nature has been utilized in sensing and timekeeping fields due to its numerous advantages, including amplitude and frequency stabilization, noise reduction, and sensitivity improvement. However, the limited synchronization bandwidth hinders its broader application, and few techniques have been explored to enhance this aspect. In this paper, we conducted theoretical and experimental studies on the unidirectional synchronization characteristics of a resonator with phase lock loop oscillation. A novel enhancement method for the synchronization bandwidth using a parametrically excited MEMS oscillator is proposed, which achieves a remarkably large synchronization bandwidth of 8.85 kHz, covering more than 94% of the hysteresis interval. Importantly, the proposed method exhibits significant potential for high-order synchronization and frequency stabilization compared to the conventional directly excited oscillator. These findings present an effective approach for expanding the synchronization bandwidth, which has promising applications in nonlinear sensing, fully mechanical frequency dividers, and high-precision time references.

An eco-friendly versatile superabsorbent hydrogel based on sodium alginate and urea for soil improvement with a synchronous chemical loading strategy.

In this paper, an eco-friendly versatile superabsorbent material was designed for soil improvement, and a synchronous chemical loading strategy was proposed. In this strategy, urea not only acted as fertilizer but also acted as a crosslinker to construct an alginate network. The microstructure, chemical structure, thermal stability and composition of the obtained SA/urea hydrogel were characterized in detail. Adsorption behavior and application performance in agriculture were evaluated. The results demonstrated that urea had two different conformations in the network. The SA/urea hydrogel had abundant pore structures with excellent water absorption performance. It could not only improve the water retention capacity of soil but also release nitrogen, phosphorus and potassium elements with degradation for as long as 9 weeks. Moreover, the hydrogel could promote plant growth, increase the nutritional composition of plants and inhibit the accumulation of harmful nitrate in plants. With advantages, including biodegradability, high water absorption, controllable degradation, excellent water retention, sustained NPK release and improved plant nutrition value, the SA/urea hydrogel has great potential for soil improvement in agriculture as an eco-friendly versatile water retention agent and can be expected to extend to more fields as a novel superabsorbent material.

Enhanced sulfamethazine detoxification by a novel BiOCl (110)/NrGO/BiVO4 heterojunction.

The emerging contaminants removal from the environment has recently been raised concerns due to their presence in higher concentrations. Over usage of emerging contaminant such as sulfamethazine poses serious threat to the aquatic and human health as well. This study deals with rationally structured a novel BiOCl (110)/NrGO/BiVO4 heterojunction which is used to detoxify sulfamethazine (SMZ) antibiotic efficiently. The synthesised composite was well characterized and the morphological analysis evidenced the formation of heterojunction consisted of nanoplates BiOCl with dominant exposed (110) facets and leaf like BiVO4 on NrGO layers. Further results revealed that the addition of BiVO4 and NrGO tremendously increased the photocatalytic degradation efficiency of BiOCl with the rate of 96.9% (k = 0.01783 min-1) towards SMZ within 60 min of visible light irradiation. Furthermore, heterojunction energy-band theory was employed to determine the degradation mechanism of SMX in this study. The larger surface area of BiOCl and NrGO layers are believed to be the reason for higher activity which facilitates the excellent charge transfer and improved light absorption. In addition, SMZ degradation products identification was carried out by LC-ESI/MS/MS to determine the pathway of degradation. The toxicity assessment was studied using E. coli as a model microorganism through colony forming unit assay (CFU), and the results indicated a significant reduction in biotoxicity was observed in 60 min of degradation process. Thus, our work gives new methods in developing various materials that effectively treat emerging contaminants from the aqueous environment.

Frequency unlocking-based MEMS bifurcation sensors.

MEMS resonators exhibit rich dynamic behaviors under the internal resonance regime. In this work, we present a novel MEMS bifurcation sensor that exploits frequency unlocking due to a 1:3 internal resonance between two electrostatically coupled micro-resonators. The proposed detection mechanism allows the sensor to operate in binary (digital) and analog modes, depending on whether the sensor merely detects a significant jump event in the peak frequency upon unlocking or measures the shift in the peak frequency after unlocking and uses it in conjunction with a calibration curve to estimate the corresponding change in stimulus. We validate the success of this sensor paradigm by experimentally demonstrating charge detection. High charge resolutions are achieved in binary mode, up to 0.137 fC, and in analog mode, up to 0.01 fC. The proposed binary sensor enables extraordinarily high detection resolutions due to the excellent frequency stability under internal resonance and the high signal-to-noise ratio of the shift in peak frequency. Our findings offer new opportunities for high-performance ultrasensitive sensors.

High mobility group box 1 and homocysteine as preprocedural predictors for contrast-induced acute kidney injury after percutaneous coronary artery intervention.

PURPOSE: High mobility group box 1 (HMGB1) and homocysteine (Hcy) play important roles in contrast-induced acute kidney injury (CI-AKI). We compared HMGB1 to Hcy as preprocedural predictors for CI-AKI in coronary artery disease (CAD) patients after percutaneous coronary artery intervention (PCI). METHODS: We included 257 eligible patients who were categorized into CI-AKI ( +) and CI-AKI ( -) group. The differences in clinical characteristics and biochemical indexes between two groups were analyzed. RESULTS: We observed that thirty-eight (14.8%) of 257 eligible CAD patients developed CI-AKI. HMGB1 (14.65 [11.13-24.89] vs 10.88 [7.94-13.23], p < 0.001) and Hcy (14.07 [12.07-17.31] vs 12.09 [10.71-13.47], p < 0.001) increased significantly in CI-AKI ( +) group. Both age (r = 0.210, p = 0.001), serum creatinine (r = 0.509, p < 0.001), eGFR (r = - 0.459, p < 0.001) and Hcy (r = 0.531, p < 0.001) were significantly correlated with HMGB1. Among all patients, HMGB1 (OR 1.181, 95% CI 1.081-1.290, p < 0.001) and Hcy (OR 1.260, 95% CI 1.066-1.489, p = 0.007) were independent predictors for the development of CI-AKI. We built the propensity score matching (PSM) using 38 pairs of patients. After adjustment, HMGB1 (OR 1.169, 95% CI 1.035-1.322, p = 0.012) and Hcy (OR 1.457, 95% CI 1.064-1.997, p = 0.019) were also independent predictors for the development of CI-AKI. Both HMGB1 (AUC: 0.704, 95% CI: 0.588-0.819, p = 0.002) and Hcy (AUC: 0.708, 95% CI: 0.593-0.823, p = 0.002) had predictive values for CI-AKI. CONCLUSION: There is a significant positive association between HMGB1 and Hcy in CAD patients. Both HMGB1 and Hcy are potential preprocedural predictors of CI-AKI after PCI.

Association between serum HER2/ErbB2 levels and coronary artery disease: a case-control study.

BACKGROUND: Research has associated human epidermal growth factor receptor (HER2) with glucose and lipid metabolism. However, the association between circulating HER2 levels and coronary artery disease (CAD) remains to be elucidated. METHODS: We performed a case-control study with 435 participants (237 CAD patients and 198 controls) who underwent diagnostic coronary angiography from September 2018 to October 2019. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for CAD were calculated with multiple logistic regression models after adjustment for confounders. RESULTS: Overall, increased serum HER2 levels were independently associated with the presence of CAD (OR per 1-standard deviation (SD) increase: 1.438, 95% CI 1.13-1.83; P = 0.003) and the number of stenotic vessels (OR per 1-SD increase: 1.399, 95% CI 1.15-1.71; P = 0.001). In the subgroup analysis, a significant interaction of HER2 with body mass index (BMI) on the presence of CAD was observed (adjusted interaction P = 0.046). Increased serum HER2 levels were strongly associated with the presence of CAD in participants with BMI ≥ 25 kg/m2 (OR per 1-SD increase: 2.143, 95% CI 1.37-3.35; P = 0.001), whereas no significant association was found in participants with BMI < 25 kg/m2 (OR per 1-SD increase: 1.225, 95% CI 0.90-1.67; P = 0.201). CONCLUSION: Elevated HER2 level is associated with an increased risk of CAD, particularly in people with obesity. This finding yields new insight into the pathological mechanisms underlying CAD, and warrants further research regarding HER2 as a preventive and therapeutic target of CAD.

Association between serum angiopoietin-2 concentrations and periprocedural myocardial injury in patients undergoing elective percutaneous coronary intervention.

Angiopoietin-2 (Ang-2) is a proangiogenic factor that mediates inflammation and atherosclerosis. We evaluated the predictive value of circulating Ang-2 levels for periprocedural myocardial injury (PMI) in 145 patients undergoing elective percutaneous coronary intervention (PCI), and investigated whether post-PCI Ang-2 levels are influenced by PMI. PMI was defined as a post-procedural troponin elevation above the 5×99th percentile upper reference limit. Blood samples for Ang-2 analysis were collected at admission and on postoperative days 1 and 3. PMI occurred in 40 patients (28%). At baseline, there was no difference in Ang-2 levels between PMI and non-PMI patients (P=0.554). However, a significant interaction effect between PMI occurrence and time on Ang-2 levels was observed (interaction P=0.036). Although serum Ang-2 levels in non-PMI patients gradually decreased, Ang-2 levels in PMI patients did not change between different time-points. Multiple logistic regression analysis revealed that age, total stent length, and serum levels of N-terminal pro-brain natriuretic peptide were independent PMI predictors. These findings indicate that pre-procedural Ang-2 levels do not impact PMI occurrence after elective PCI. However, changes in Ang-2 levels after the procedure are closely related to PMI.

High molecular weight poly(butylene succinate-co-butylene furandicarboxylate) copolyesters: from catalyzed polycondensation reaction to thermomechanical properties.

Novel potentially biobased aliphatic-aromatic copolyesters poly(butylene succinate-co-butylene furandicarboxylate) (PBSFs) in full composition range were successfully synthesized from 2,5-furandicarboxylic acid (FA), succinic acid (SA), and 1,4-butanediol (BDO) via an esterification and polycondensation process using tetrabutyl titanate (TBT) or TBT/La(acac)(3) as catalyst. The copolyesters were characterized by size exclusion chromatography (SEC), Fourier transform infrared (FTIR), (1)H NMR, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and their tensile properties were also evaluated. The weight average molecular weight (M(w)) ranges from 39,000 to 89,000 g/mol. The copolyesters are random copolymers whose composition is well controlled by the feed ratio of the diacid monomers. PBSFs have excellent thermal stability. The glass transition temperature (T(g)) increases continuously with φ(BF) and agrees well with the Fox equation. The crystallizability and T(m) decrease with increasing butylene furandicarboxylate (BF) unit content (φ(BF)) from 0 to 40 mol %, but rise again at φ(BF) of 50-100 mol %. Consequently, the tensile modulus and strength decrease, and the elongation at break increases with φ(BF) in the range of 0-40 mol %. At higher φ(BF), the modulus and strength increase and the ultimate elongation decreases. Thus, depending on φ(BF), the structure and properties of PBSFs can be tuned ranging from crystalline polymers possessing good tensile modulus (360-1800 MPa) and strength (20-35 MPa) to nearly amorphous polymer of low T(g) and high elongation (~600%), and therefore they may find applications in thermoplastics as well as elastomers or impact modifiers.