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To compare the clinical and economic effects of ultrasound (US)-guided radiofrequency ablation (RFA) with parathyroidectomy (PTX) for primary hyperparathyroidism (PHPT). From April 2014 to April 2021, 123 PHPT patients who received US-guided RFA or PTX were studied. Propensity score (PS) matching was used to balance the baseline data of the two groups. The rates of cure, recurrent and persistent PHPT, and complications were compared. A Chinese healthcare system perspective cost minimization analysis was conducted. After PS matching, 37 patient pairs (1:1) were created for the two groups. Follow-up was 27.2 ± 10.6 months and 28.8 ± 16.1 months for the RFA and PTX groups, respectively. At the last follow-up, there was no evidence of differences regarding clinical cure rate between the two groups (RFA vs. PTX, 91.9% vs. 94.6%, p = 1.000). Recurrent PHPT did not develop in any patient. One patient in each group had persistent PHPT. The incidence of complications and side effects, except postoperative pain (RFA vs. PTX, 16.2% vs. 40.5%, p = 0.020), were no significant difference between the two groups (all, p > 0.05). The incremental cost was −$284.00; thus, RFA was more cost-effective. For patients with employee medical insurance or resident medical insurance, the incremental costs (RFA vs. PTX) were −$391.94 and −$49.43, respectively. There were no significant differences in efficacy and safety between RFA and PTX. As the incremental cost for RFA compared with PTX was negative, RFA may be used as a more cost-effective nonsurgical treatment alternative for PHPT. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA)-based therapies have shown great potential in the repair of spinal cord injury (SCI). MicroRNA 21 (miR21) has been proven to have an essential protective effect on SCI. However, there are some challenges for miRNAs application due to their easy degradation and ineffective cell penetration. As natural vesicles, exosomes were considered ideal carriers for miRNAs delivery for their advantages of low immunogenicity, inherent stability and tissue/cell penetration. However, poor targeting and the low capacity of specific miRNAs impede their practical applications. This study aims to develop a type of genetically engineered miR21-loaded exosomes that can be entrapped in collagen-I (Col-I) scaffold to repair SCI. The collagen-binding domain (CBD)-fused lysosome-associated membrane glycoprotein 2b (Lamp2b) protein (CBD-LP) and miR21 were overexpressed in host HEK293T (293T) cells that were used to produce engineered miR21-loaded exosomes. The CBD peptide fused in Lamp2b on the exosome surface can stably tether exosomes to Col-I scaffold, facilitate the retention of miR21-loaded exosomes in lesion sites, promote the sustained release of miR21 to cells. Finally, a functionalized Col-I scaffold biomaterial enriched with miR21-loaded exosomes was developed and it could benefit the repair of SCI. MiRNA-based therapeutics have promising potential in spinal cord injury (SCI) repair. However, easy degradation and ineffective cell penetration impede miRNAs application. Exosomes are natural vehicles for miRNAs delivery but face the challenge of diffusion in vivo. Here, the collagen-binding domain (CBD)-fused Lamp2b and miR21 were overexpressed in HEK293T cells to produce miR21-loaded and CBD-modified exosomes (CBD-LP-miR21-EXOs). The CBD modified on the exosome surface can stably tether exosomes to collagen-I scaffold to form functionalized CBD-LP-miR21-EXO-Col scaffold that can facilitate the retention of miR21-loaded exosomes, promote the sustained release of miR21 to cells and finally benefit SCI repair. Furthermore, this type of functionalized collagen-I materials can be widely applied for other tissue injury repairs by enriching the CBD-LP-EXOs loaded with appropriate miRNAs. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper focuses on the stable tracking control of the manipulator with constrained communication, unmeasurable velocity, and nonlinear uncertainties. An NN observer-depended output feedback scheme in the discrete-time domain is developed by virtue of the model-based dynamic event-triggered backstepping technique in the channel of sensor to controller. For generalizing the zero-order-holder (ZOH) implementation, a plant model is built to approximate the triggered states in the time flow, and according to which, the control law is fabricated. Based on model-based error events, we construct a dead-zone triggered condition with a dynamically adjustable threshold, making the threshold evolve with the system performance, to achieve flexible communication scheduling and avoid the accumulation of triggers in small tracking errors. The internal and external nonlinear uncertainties are online compensated by the neural network, and the aperiodic adaptive law is derived in the sense of control stability to save the computation. Finally, the conditions for semi-global ultimate uniform bounded (SGUUB) of all variables are given via impulse Lyapunov analysis, and a positive lower bound in the time interval between consecutive executions to guarantee the Zeno free behavior is obtained. Simulations are conducted on a three-link manipulator to illustrate the effectiveness of our method. • Adaptive model-based dynamic event-triggered feedback control NN is proposed. • A NN-based observer is applied to estimate the velocity. • Dead-zone triggered condition with dynamically threshold is constructed. • The internal and external nonlinear uncertainties are online compensated by our NN. • The aperiodic adaptive law is derived in the sense of control stability. [ABSTRACT FROM AUTHOR]

This paper proposes a neural network-based model predictive control (MPC) method for robotic manipulators with model uncertainty and input constraints. In the presented NN-based MPC structure, two groups of radial basis function neural networks (RBFNNs) are considered for online model estimation and effective optimization. The first group of RBFNNs is introduced as a predictive model for the robotic system with online learning strategies for handling the system uncertainty and improving the model estimation accuracy. The second one is developed for solving the optimization problem. By taking into account an actor–critic scheme with different weights and the same activation function, adaptive learning strategies are established for balancing between optimal tracking performance and predictive system stability. In addition, aiming at guaranteeing the input constraints, a nonquadratic cost function is adopted for the NN-based MPC. The ultimately uniformly boundedness (UUB) of all variables is verified through the Lyapunov approach. Simulation studies are conducted to explain the effectiveness of the proposed method. • An NN-based model predictive control structure containing two groups of NNs is proposed for robotic manipulators. • The model predictive controller presents good tracking performance for robotic manipulators. • The adaptive predictive model based on neural networks is established against model uncertainties without pre-training. • The actor–critic scheme is developed for balancing between optimal tracking performance and system stability. • The stability of the closed-loop system is proven by the Lyapunov method. [ABSTRACT FROM AUTHOR]

This paper presents a fast computational framework for seismic random response of multi-support structures, of which computational efficiency handers its application to practical engineering. First of all, after structural modelling based on the finite element method, the large mass method is used to exert the load on the supports in the form of seismic acceleration history, which ensures that the equations of motion of the system are solved directly. Secondly, the impulsive load is exerted on the supports and corresponding dynamic analysis is carried out. On the basis of the impulsive response, a generalized frequency response function (FRF) can be obtained via the Fourier transform. Thirdly, according to classic formulation, auto power spectrum density (PSD) functions of structural response may be calculated, which involves the generalized FRFs and the PSD function matrix of the seismic accelerations at the supports. The proposed framework is verified by comparing its computational results with the analytical solution of a single DOF system. A 5-span bridge during earthquakes is taken as a case study. The results show that three factors influencing spatial variation of seismic ground motion should be taken into consideration to get safer random response of a multi-support structure. [ABSTRACT FROM AUTHOR]

Abstract: Variants in the gene encoding transcription factor 7-like 2 (TCF7L2) are associated with type 2 diabetes mellitus (T2D) in several ethnic groups. Two intronic variants, rs290487 and rs11196218, were originally identified as T2D modifiers in Hong Kong Chinese and Taiwan Chinese populations, respectively. However, discrepancies were noted in subsequent replicated studies. In this study, an association of these two loci with T2D was investigated in a Harbin Chinese population. Whereas the two populations in the initial studies were southern Han Chinese, Harbin Chinese are from northeastern China. The SNPs rs290487 and rs11196218 were genotyped by ligase detection reactions in 700 T2D patients and 570 unrelated non-diabetic controls. Association analyses, which were carried out using the case-control sample set, yielded a significant association between rs290487 and T2D, with a trend opposite to that described in a previous report. Specifically, rs290487T was found to be significantly associated with disease susceptibility (p =0.039), and the allelic OR of rs290487T carriers was 1.184 (95% CI 1.008–1.391). There was no significant association between rs11196218 and T2D. Taken together, TCF7L2 may be an important susceptibility gene for T2D in some Chinese populations. The discrepancies in the allelic associations determined for northern vs. southern Chinese allude to the presence of genetic variation among the Han Chinese. [Copyright &y& Elsevier]

An immune optimization algorithm is proposed in this paper based on the immune negative selection. The algorithm NSIOA is motivated by the negative selection mechanism in biological immune recognition. Different from the existing immune optimization methods, NSIOA constantly removes the worst solutions to get the optimal solution. Considering that removal of poor members of a population might lead to the loss of design information that may actually help identify better solutions in the search space, the proposed NSIOA is designed to keep the diversity of antibodies while removing poor members, therefore the algorithm will converge to global optimal solution with high probability. The convergence property and the complexity of the algorithm have also been analyzed. To illustrate the efficiency of the algorithm is used in solving the travel salesman problem. The theoretical analysis and experimental results show that the algorithm is of a strong potential in solving practical problems. [Copyright &y& Elsevier]

Mg-based nanofluid fuel is a promising fuel for propulsion system in Mars exploration. In this study, Mg-based nanofluid fuel were prepared by one-step method, and the effect of Mg(magnesium) content, Mg size(68 μm,110 μm,175 μm), and oleic acid (OA) on droplet ignition and combustion under the atmosphere of 90 % CO 2 and 10 % O 2 were investigated. According to the TG-DSC results, 68 m Mg particles under CO 2 had the highest exothermic efficiency of 4472 J/g. The combustion of Mg/OA/kerosene droplets consists of five stages: ignition, d2-law combustion, micro-explosion, vapor flame extinguishment, and agglomerate explosion. The ignition delay time of Mg (68 μm, 5 %)/kerosene is 0.045s, which is half that of kerosene (0.0890s). The agglomerates explode violently and emit a brilliant white light at the end of the Mg-based nanofluid fuel combustion. The explosive effect of Mg agglomerates diminishes as the Mg content increases. The rate of combustion decreases with increasing particle size. In the sample with added oleic acid, Mg (68 μm, 5 %)/OA/kerosene shows the best combustion rate of 0.6320 mm2/s. Finally, a numerical model for the combustion of Mg-based nanofluid fuel droplets is proposed. The predictions are within 2 % of the experimental results. The findings are expected to explore future in-situ utilization of CO 2 on the Mars surface. • Combustion characteristics of a novel Mg-based nanofluid fuel for Mars are studied. • Effects of Mg particle size and content on the combustion properties are analyzed. • The optimal Mg-based nanofluid fuel formulation is Mg (5 wt%, 68um)/OA/kerosene. • A numerical model for the combustion of Mg-based nanofluid fuel droplet is proposed. [ABSTRACT FROM AUTHOR]

• Accurate identification of the different stage of Alzheimer's disease is essential for early prevention of disease. • Sparse logistic regression with the generalized elastic net improves is proposed for the early diagnosis of Alzheimer's disease. • The sparsity brought by the generalized elastic net makes the model capable of selecting the most discriminative brain regions and achieving excellent classification performance. Accurate prediction of high-risk group who may convert to Alzheimer's disease (AD) patients is critical for the future treatment of patients. Recently, logistic regression is used for the early diagnosis of AD. However, due to the high-dimensional small sample characteristics of AD data, this brings difficulties to logistic regression-aided diagnosis. To solve the problem, in this paper, we propose sparse logistic regression with the generalized elastic net for the early diagnosis of AD. The generalized elastic net is composed of Lp regularization and L 2 regularization. The Lp regularization can produce sparse solutions. L 2 regularization ensures that the correlated brain regions are in solution. We evaluate our proposed method on 197 subjects from the baseline MRI data of ADNI database. Our proposed method achieves classification accuracy of 96.10, 84.67, and 75.87 %, for AD vs. HC, MCI vs. HC, and cMCI vs. sMCI, respectively. Experimental results show that, compared with previous methods, our proposed method captures distinct brain regions that are significantly related to AD conversion and provides a significant enhancement in AD classification. [ABSTRACT FROM AUTHOR]

The Mg-based propellant is considered to be a promising fuel for underwater propulsion, but the mechanism of the change of the burning rate is unclear. The Mg-based propellant was divided into two parts on the basis of the BDP multi-flame model: large-size oxidizer particle and pseudo-propellant consisting of fine oxidizer and other components, and the micro steady-state combustion model of Mg-based propellant was established. Quantitatively analysis on the gas-phase multi-flame structure was performed, which focused on the effect of pressure, Mg content, and oxidizer particle size on the burning rate. This model was verified by the results of combustion experiments on ammonium perchlorate (AP) /hydroxyl‑terminated polybutadiene (HTPB) composite propellant and Mg-based propellant, and the mean absolute percentage error between the burning rate obtained from the simulation and the experimental measurements was less than 5%. Results indicated that the flame structure of Mg-based propellant exhibited typical BDP flame characteristic. As pressure increased from 1 MPa to 4 MPa, the premixed AP flame and the preliminary diffusion flame were closer to the burning surface, which enhanced the heat feedback. And accordingly, the burning rate raised from 5.93 mm/s to 9.79 mm/s. Mg content mainly affect the combustion process of the pseudo-propellant. The premixed flame above the pseudo-propellant gradually disappeared as the Mg content increased from 15% to 63%, which led the burning rate to decrease from 17.45 mm/s to 7.83 mm/s. AP particle size affected the effectiveness of the preliminary diffusion flame on the burning surface and resulted in a change in the burning rate. These findings can provide theoretical guidance for the design of Mg-based propellant formulations. [ABSTRACT FROM AUTHOR]

Abstract Renewable energy plays a significant role in climate change mitigation and energy transition. China has established demonstration cities for energy transition and renewable energy development. However, the assessment system for these implementations is relatively blank. This study develops an index system to guide the construction of energy transition demonstration project and optimize energy transition development at the city level. The genetic algorithm-based analytic hierarchy process is employed to form energy transition strategies in the cities of Guiyang, Tongren, Zhangjiakou, and Nanning. The priority values of different renewable energy technologies are given for the cities. The results show that resource endowment is not the only driver for the priority due to the unique combination of influence factors in decision. The assessment system can help avoid the problems of single operating mode and over-investment in the process of energy transition so as to find the benchmark for energy structure adjustment. Finally, some policy recommendations are made for city-scale energy transition. Highlights • An index for city-scale energy transition in China is developed. • The genetic algorithm-based AHP is employed for indicator importance. • The priority of renewable energy development is given for cities. [ABSTRACT FROM AUTHOR]

Abstract: Dietary cholesterol and aging are major risk factors to accelerate oxidation process for developing hypercholesterolemia. The major aim of this study is to elucidate the effects of rice protein on cholesterol level and oxidative stress in adult rats fed with and without cholesterol. After 2weeks of feeding, hepatic and plasma contents of cholesterol, reduced glutathione (GSH), oxidized glutathione (GSSG), malondialdehyde (MDA) and protein carbonyl (PCO) were measured. In liver, total antioxidative capacity (T-AOC), activities of antioxidant enzymes (total superoxide dismutase, T-SOD; catalase, CAT), glutathione metabolizing enzyme activities and gene expression levels (γ-glutamylcysteine synthetase, γ-GCS; glutathione reductase, GR; glutathione peroxidase, GPx) were determined. Under cholesterol-free/enriched dietary condition, T-AOC, activities of T-SOD and CAT, glutathione metabolism related enzymes' activities and mRNA levels (γ-GCS, GR and GPx) were effectively stimulated by rice proteins as compared to caseins. Compared with caseins, rice proteins significantly increased hepatic and plasma GSH contents, whereas hepatic and plasma accumulations of MDA, PCO and GSSG were significantly reduced by rice protein-feedings. As a result, the marked reductions of cholesterol in the plasma and in the liver were observed in adult rats fed rice proteins with and without cholesterol. The present study demonstrates that the hypocholesterolemic effect of rice protein is attributable to inducing antioxidative response and depressing oxidative damage in adult rats fed cholesterol-free/enriched diets. Results suggest that the antioxidant capability involved in the hypocholesterolemic action exerted by rice protein is independent of dietary cholesterol during adult period. [Copyright &y& Elsevier]

Abstract: Spinel Li4Ti5− x Zr x O12 (0⩽ x ⩽0.25) materials were prepared by a solid-state reaction method using Li2CO3, ZrO2 and TiO2 as raw material, and the structure and electrochemical performance of the material were investigated by TG–DTA, XRD, SEM, CV, EIS and charge–discharge tests. The Zr-doped Li4Ti5O12 materials show much improved rate capability and specific capacity compared with pristine Li4Ti5O12. Especially, the pristine Li4Ti5O12 offers about 111mAhg−1, but Li4Ti4.9Zr0.1O12 delivers a remarkable capacity of 172mAhg−1 at 2C charge–discharge rate. Li4Ti4.9Zr0.1O12 sample delivers a capacity of 155mAhg−1 even after 150cycles at 5C charge–discharge rates, implying the possibility for high power applications, such as HEV and PHEV. The rate capability of the anode material made from the modified powder is significantly improved when discharged at high current rates due to the reduced charge transfer resistance and fast lithium insertion/extraction kinetics. [Copyright &y& Elsevier]

Abstract: Shallow, eutrophic lakes are usually characterized by a turbid state devoid of submerged vegetation subject to human-induced eutrophication. In most cases, it is rather hard to restore a vegetated clear state due to reduced resilience caused by a blend of complicated factors. In this study, we successfully reestablished a plant community in a small hypereutrophic lake over a certain period. In winter and spring with transparency of >55cm and temperature of <20°C, a submerged stands bed formed gradually under strong human interventions. The reestablished plant bed displayed obvious seasonal succession and prolonged the clear-water stage until July 2005, when it collapsed. The regime shift to a turbid state was mainly attributed to the decreasing biomass of stands bed and mechanical damage brought about by the elimination of Spirodela polyrhiza, increasing water temperature, P concentration as well as periphyton biomass, etc. The reestablishment also changed the aquatic ecosystem greatly. A ‘clear-water’ stage was characterized by higher NO3 −–N, NH4 +–N, electrical conductivity, transparency and TN/TP level and more cladocerans (mainly Daphnia pulex), while the turbid state was characterized by higher temperature, chlorophyll a and TP level and more abundant rotifers. It is thus viable to restore submerged macrophytes in such lakes in winter and spring, when transparency is relatively high while temperature and water level are low. Nevertheless, to obtain a long-term, vegetated clear state, control of internal nutrient loading by means of obstruction, purification, dredging or solidification, is extremely necessary since nutrients play an important role in regime shifts as evidenced by the present case, too. [ABSTRACT FROM AUTHOR]

A vertical/reverse-vertical flow constructed wetland system was set up in Wuhan, China, to study its treatment efficiency of polluted lake water. The numbers of substrate microorganisms and urease activities in the substrate of the constructed wetland were determined by plate counts and colorimetric analysis, respectively. The removal efficiencies of biochemical oxygen demands (BOD5), chemical oxygen demands (COD), total phosphorus (TP), total Kjeldahl nitrogen (TKN), and total suspended solids (TSS) were measured by EPA approved methodology. The results showed there were significant positive correlations (P<0.05) between numbers of microorganism in the substrate and removal rates of TKN and CODCr. Meanwhile, there was significant positive correlation (P<0.05) between urease activities and removal efficiencies of TKN and negative correlation between urease activities and removal efficiencies of BOD5. Substrate microorganisms and urease activities played key factors during purification processes and they could be utilized as indicator of wastewater treatment performances in the constructed wetland system. [Copyright &y& Elsevier]

The effects of the flocculant composed of autoclaved fly-ash brick and chitosan for algae Microcystis aeruginosa removal were investigated. The results showed that when 1 mL flocculant was added in 25 mL algae suspension, which initial density was 10 6 cells/mL, the removal rate of algae reached 88.4%. In order to enhance the removal efficiency, pre-oxidation with KMnO 4 was studied. The results indicated that it could improve algae coagulation removal by 9.44% when it was pre-oxidized by KMnO 4 with the concentration of 0.9 mg/L. The cells of M. aeruginosa sunk quickly, thus the algal cells were removed completely. In conclusion, the combined flocculant owns the advantages of low concentration, short reaction time, and could be employed for algae control. [ABSTRACT FROM AUTHOR]

Clustering analysis is an important data mining method for data stream. In this paper, a self-adaption neighborhood density clustering method for mixed data stream is proposed. The method uses a significant metric criteria to make categorical attribute values become numeric and then the dimension of data is reduced by a nonlinear dimensionality reduction method. In the clustering method, each point is evaluated by neighborhood density. The k points are selected from the data set with maximum mutual distance after k is determined according to rough set. In addition, a new similarity measure based on neighborhood entropy is presented. The data points can be partitioned into the nearest cluster and the algorithm adaptively adjusts the clustering center points by clustering error. The experimental results show that the proposed method can obtain better clustering results than the comparison algorithms on the most data sets and the experimental results prove that the proposed algorithm is effective for data stream clustering. [ABSTRACT FROM AUTHOR]

Umbilical cord mesenchymal stem cells (UCMSCs) have shown great potentials in regenerative medicine for their extensive sources, multilineage differentiation potential, low immunogenicity and self-renewal ability. However, the clinical application of UCMSCs still confronts many challenges including the requirement of large quantity of cells, low survival ability in vivo and the loss of main original characteristics due to two-dimensional (2D) culture. The traditional three-dimensional (3D)-spheroid culture can mimic in vivo conditions, but still has limitations in clinical application due to large size of spheroid against direct injection and inner cell death. Based on self-renewal tenet, we produced single cell derived sphere (SCDS) of UCMSCs through combining single cell pattern on chip with 3D culture. Compared with the 2D and traditional 3D culture, SCDS culture has many advantages to meet clinical requirements, including small size, higher abilities of survival and migration, and stronger hypoxia resistance and stemness maintenance. Furthermore, SCDS culture promotes angiogenesis in UCMSCs-xenografts and displays greater therapeutic potential on acute liver failure (ALF) in vivo. Our results suggest that SCDS culture may serve as a simple and effective strategy for UCMSCs optimization to meet clinical demand. [ABSTRACT FROM AUTHOR]

Papillary thyroid carcinoma (PTC) is a common endocrine tumor. This study found that different iodine concentrations affected the proliferation, apoptosis, and migration of PTC. For this study, we collected clinical information from PTC patients and monitored the levels of urinary iodine, LC3-II, and caspase-3 in cancer tissue, and BRAF kinase in peripheral blood from PTC patients. We also monitored the proliferation, apoptosis and migration ability of human papillary-thyroid carcinoma (BCPAP) cells at different iodine concentrations and their association with changes in autophagy and BRAF kinase activity of BCPAP cells at high iodine levels (10−3 mol/l). We found that the proportion of tumor diameters ≥ 1 cm in the iodine excess group were lower than that in the iodine non-excess group. The proportion of PTC patients with infiltration in the iodine excess group was higher than that in the iodine non-excess group. Levels of the autophagy-related protein LC3-II and the apoptosis-related protein caspase-3 in cancer tissues, and activity of BRAF kinase in peripheral blood, were positively correlated with urinary iodine concentrations from PTC patients. At high iodine levels, the proliferation rate decreased, and apoptosis percentage and migration rates increased compared with the no-iodine group. At high iodine levels, the frequencies of autophagosomes (Aph) and autophagosome-lysosomes (Apl) in BCPAP cells increased significantly, and activities of LC3-II and BRAF kinase increased, respectively. The activity of LC3-II decreased when BRAF kinase was inhibited. The activity of LC3-II and the proliferation and migration rates of BCPAP cells decreased, and the apoptosis percentage increased when autophagy was inhibited at high iodine concentrations. Our results demonstrated that, in the presence of excessive iodine, the mean tumor size of PTC patients was smaller and easier to invade than tumors in patients not supplied with excessive iodine. The levels of autophagy and apoptosis in PTC cancer tissues, and activities of BRAF kinase in peripheral blood increased with increasing urinary iodine concentrations. High iodine levels inhibited cell proliferation and promoted apoptosis and migration of PTC cells. Autophagy induced by BRAF kinase in PTC cells was involved in anti-apoptosis, and promoted proliferation and migration at high iodine concentrations. This study provides a rationale for iodine supplementation in PTC patients. [ABSTRACT FROM AUTHOR]