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A biphenylene network BN structure (bpn-BN) was proposed theoretically based on the pioneering work on the newly experimentally synthesized biphenylene network C which has triggered a worldwide tide of research on its family material counterparts.

Artificial Intelligence (AI) technology has been empowered to be a significant driven force within the edge context for powering up contemporary complex systems, such as smart critical infrastructure. Interconnectivity between physical and cyber spaces further introduces the needs of digital twin, which allows AI-based solutions to optimize various tasks in physical operations. However, due to the complexity of the setting in digital twin, task allocation is encountering multiple challenges, such as concurrent meeting the requirements of energy saving, efficiency, and accuracy. In this work, we propose a Digital Twin-Enabled Edge AI (DTE2AI), supported by our Energy-aware High Accuracy Strategy (EAHAS), which focuses on optimizing the training accuracy of AI tasks under the limits of training time and energy consumption. The average of the training accuracy was enhanced 12% based on our experiment evaluations.

Objectives This study’s objective was to explore the possibility of clinical evaluation of digestive system’s cancer with or without AKI patients’ cardiac function measured by impedance cardiography (ICG, Bioz. Cardio Dynamics, USA); then, try to analyze the possible reason of cardiac function changing, and to approach the independent risk factors for it. Methods Patients who were admitted to the Fourth hospital of Hebei Medical University, China between May 1st, 2019 and February 15th, 2022 were involved. A total of 51 patients with digestive system’s cancer with AKI or without AKI (31 men and 20 women, mean age 61.1 ± 10.9 year) were evaluated to routine ICG. Of the total, 19 patients were assessed to both ultrasound cardiography (UCG) and ICG. Result There were significant positive correlation with the cardiac function parameters, such as cardiac output (CO), cardiac index (CI), stroke volume (SV), left cardiac work index (LCWI) and ejection fraction (EF), measured by ICG and UCG. The relationship was observed between COICG and COUCG (r = 0.707, P = 0.001); CIICG and CIUCG (r = 0.718, P = 0.001); SVICG and SVUCG (r = 0.837, P ICG and EFUCG (r = 0.540, P = 0.017). The cardiac function parameters measured by ICG were statistically significant between cancer with AKI and without AKI patients (P

We aimed to investigate whether the use of intravenous paracetamol (IVP) preoperatively in intertrochanteric fracture (IF) patients aged 65 years or over receiving intramedullary fixation had significantly benefits on the pain score at discharge, delirium incidence, length of hospital stay (LOS), functional outcomes, and mortality. A retrospective analysis of all surgically treated patients presenting with IF was conducted at a single Level I trauma center in China between Jan. 2016 and Jan. 2020. The data concerning patients’ demographics, injury-related data, surgery-related data, operation-related data, in-hospital data, and postoperative outcomes were extracted. To minimize potential confounding and selection bias, the propensity score matching (PSM) method was performed via the caliper matching method by using a 1 : 1 ratio. After PSM, McNemar’s chi-square tests were used to examine the association of using IVP with outcome analyses. The Spearman correlations of IVP using, pain scores, and the factors which may influence them were also computed. After screening 2963 consecutive patients, 2166 were included finally, including 1576 in the non-IVP group and 590 in the IVP group. After PSM, 531 remained in each group. The pain scores at discharge were significantly between the two groups before and after matching (all p < 0.001 ). The differences of delirium rate and functional outcomes became significant after propensity score-based matching ( p = 0.001 and 0.033, respectively), although they were not significant before matching. No significant difference was observed in other operation-related data, LOS, and crude mortality rates at 30-day, 90-day, and 12-month before and after PSM. In conclusion, this study highlights the need for preoperative IVP use to optimize pain control, postoperative functional recovery, and minimize pain-related comorbidities such as delirium in elderly patients with hip fracture.

The refractory diabetic wound has remained a worldwide challenge as one of the major health problems. The impaired angiogenesis phase during diabetic wound healing partly contributes to the pathological process. MicroRNA (miRNA) is an essential regulator of gene expression in crucial biological processes and is a promising nucleic acid drug in therapeutic fields of the diabetic wound. However, miRNA therapies have limitations due to lacking an effective delivery system. In the present study, we found a significant reduction of miR-31-5p expression in the full-thickness wounds of diabetic mice compared to normal mice. Further, miR-31-5p has been proven to promote the proliferation, migration, and angiogenesis of endothelial cells. Thus, we conceived the idea of exogenously supplementing miR-31-5p mimics to treat the diabetic wound. We used milk-derived exosomes as a novel system for miR-31-5p delivery and successfully encapsulated miR-31-5p mimics into milk exosomes through electroporation. Then, we proved that the miR-31-5p loaded in exosomes achieved higher cell uptake and was able to resist degradation. Moreover, our miRNA-exosomal formulation demonstrated dramatically improved endothelial cell functions invitro, together with the promotion of angiogenesis and enhanced diabetic wound healing invivo. Collectively, our data showed the feasibility of milk exosomes as a scalable, biocompatible, and cost-effective delivery system to enhance the bioavailability and efficacy of miRNAs.

In this work, the numerical simulation study of the hydrothermal flow and heat transfer process in the porous rock under 30 MPa pressure was developed. The flow and heat transfer characteristics of hydrothermal in rocks with different porosities are studied by changing the porosity of the rock. The simulation results show that the average flow velocity decreases and the average temperature increases when the porosity decreases. The velocity field and temperature field are coupled due to the nonlinear thermophysical properties of hydrothermal. The velocity field and temperature field have strongly interacted in the range of 400–450 ℃ and the effect of temperature on velocity is gradually diminishing outside the range. Most of the fluid will be "squeezed" into the crevice and the average velocity is almost three times the no-creviced case when a crevice is present. The existence of the crevice makes the total heat flux decrease from an overall perspective, and the crevice makes a large temperature gradient at the entrance and export of the crevice from a local perspective. These results provide theoretical support for the utilization of submarine hydrothermal fluid shallow circulation heat energy.

With the proportion of wind power in the grid increasing, the monitoring and maintenance of wind turbines is becoming more and more important for the reliability of the grid. In this study, a data-driven modelling framework based on deep convolutional neural networks is constructed for wind turbines condition monitoring (CM) and performance forecasting (PF). For CM, a robust denoising autoencoder (DAE) model is introduced to output the reconstruction error (RE) of raw signals. The RE is processed to a state indicator by exponentially weighted moving average (EWMA) and monitored on a control chart. For PF, two multi-steps ahead forecasting models are constructed for the forecasting of generator bearing and transformer temperature. To prevent overfitting caused by abundant features, the marginal effect analysis based on random forests is implemented to measure the importance of features. Besides, novel residual attention module (RAM) and training strategies are used improve their representation power of DAE and PF models. Experiments on a real wind turbine dataset prove the effectiveness of the proposed models and methods.

Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications in diabetes. Previous studies have shown that chronic neuroinflammation was associated with DPN. However, further research is needed to investigate the exact immune molecular mechanism underlying the pathogenesis of DPN. Expression profiles were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened by R software. After functional enrichment analysis of DEGs, a protein–protein interaction (PPI) network analysis was performed. The CIBERSORT algorithm was used to evaluate the infiltration of immune cells in DPN. Next, the least absolute shrinkage and selection operator (LASSO) logistic regression and support vector machine-recursive feature elimination (SVM-RFE) algorithms were applied to identify potential DPN diagnostic markers. Finally, the results were further validated by qRT-PCR. A total of 1308 DEGs were screened in this study. Enrichment analysis identified that DEGs were significantly enriched in immune-related biological functions and pathways. Immune cell infiltration analysis found that M1 and M2 macrophages, monocytes, resting mast cells, resting CD4 memory T cells and follicular helper T cells were involved in the development of DPN. LTBP2 and GPNMB were identified as diagnostic markers of DPN. qRT-PCR results showed that 15 mRNAs, including LTBP2 and GPNMB, were differentially expressed, consistent with the microarray results. In conclusion, LTBP2 and GPNMB can be used as novel candidate molecular diagnostic markers for DPN. Furthermore, the infiltration of immune cells plays an important role in the progression of DPN.

The choice of the type of anesthesia (TOA) used in hip fracture surgery in older adults is still controversial. The main question is not whether regional anesthesia (RA) or general anesthesia (GA) is superior, but in which patients the type of anesthesia may affect the outcome after surgery. In this retrospective analysis of surgically treated intertrochanteric fracture patients, we used propensity score matching (PSM) to investigate whether clinically relevant differences in outcomes were observed in mortality, complications, and functional outcomes between RA and GA. After screening 2934 consecutive patients, 2170 were ultimately included, including 841 in the GA group and 1329 in the RA group. After PSM, 808 remained in each group. Patients receiving GA were more prone to have a shorter duration for their operation and higher total hospital costs than patients with RA (p = 0.034 and 0.004, respectively). We also observed that the GA group has a higher rate of pulmonary complications, while the RA group has a higher rate of cardiac complications (p = 0.017 and 0.011, respectively). No significant difference was observed in mortality, functional outcomes, and other complications (all p > 0.05). The clinical innovation of this study was the potential value of GA for patients with cardiac diseases and of RA for patients with pulmonary diseases.

To satisfy the requirements of low fuel consumption, low emission, and high efficiency of the shipping industry, marine diesel engines are developing in the direction of automation and energy-saving, which increases the possibility and complexity of marine diesel engine failures. A one-dimension thermodynamic model for the marine diesel engine is built with AVL Boost software. The model is applied to a low-speed two-stroke 6S50MC diesel engine, and the error between the main performance parameters obtained by simulation and the test bench data is less than 3% under 100% and 75% load. Based on the model, 6 typical single faults and many typical double faults concomitant phenomena of diesel are reproduced. Based on the second law of thermodynamics, the exergy flow among the components and the external environment is analyzed. The thermoeconomic model of a marine diesel engine is established where the "fuel" and "product" of the components are defined according to their function. The fault diagnosis results show that the effects of faults generally propagate through the diesel engine system and affect the behavior of several components, resulting in induced malfunction in normal components. Therefore the malfunction MFi of each component is the superposition of the intrinsic malfunction and the induced malfunction according to the malfunction and dysfunction analysis. The thermoeconomic fault diagnosis method can be used to narrow the search range of abnormal components though it cannot accurately locate the fault.

We aimed to investigate whether super elderly patients aged over 90 years had significantly worse functional outcomes, perioperative complications, and survival rates. Among 3560 patients aged over 65 years presenting with intertrochanteric fractures and treated surgically between Jan 2014 and Jan 2019, 2242 patients were included, including 206 in super elderly group and 2036 in elderly group. After using propensity score matching to minimize the effects of possible confounding variables, 192 remained in each group. No significant difference was observed in functional outcomes, perioperative complications, or 30-day, 90-day, and 1-year mortality after propensity score matching and McNemar's tests (p>0.05). After an average follow-up of 37 months, the Kaplan-Meier survival curve showed no significant difference between the two groups in terms of cumulative survival rate (p=0.081, log-rank). Our data demonstrated progressive increases in mortality and poor outcomes with increasing Elixhauser comorbidity scores, which represented the severity index of patients preoperatively. Our study also found that there were weak correlations between five characteristics and the patient age. These results all suggested that it is not the advanced age itself but other concomitant factors, that appear to be responsible for the adverse functional outcomes, perioperative complications, and mortality in super elderly patients.

This paper investigates the effect of lateral and posterior 1/3 tubular plate bone plate fixation on the curative effect, wound healing, and mechanical stability of complex ankle fracture. 80 patients with complex ankle fractures treated in our hospital from January 2018 to July 2020 are selected for the study, and 80 patients are randomly divided into posterior fixation group and lateral fixation group according to the number table method, with 40 patients in each group. Patients in the posterior malleolus fixation group are treated with posterior lateral malleolus plate fixation, and patients in the lateral malleolus fixation group are treated with lateral malleolus plate fixation. The differences in efficacy, mechanical stability, wound healing, visual analog scale (VAS) pain score, and American Association of Foot and Ankle Surgery (AOFAS) ankle function are compared. The subjects are followed up for 6 months until January 2022. In patients with complex ankle fracture, 1/3 tubular plate osteoplate fixation in the posterior lateral malleolus can improve clinical efficacy and mechanical stability, which is helpful to promote incision healing and reduce the risk of complications. The 1/3 tubular plate osteoplate fixation in the posterior lateral malleolus is worthy of clinical promotion and application.

This work aimed at improving the water solubility of Ginsenoside (G)-Re by forming an inclusion complex. The solubility parameters of G-Re in alpha (α), beta (β), and gamma (γ) cyclodextrin (CD) were investigated. The phase solubility profiles were all classified as AL-type that indicated the 1:1 stoichiometric relationship with the stability constants Ks which were 22 M−1 (α-CD), 612 M−1 (β-CD), and 14,410 M−1 (γ-CD), respectively. Molecular docking studies confirmed the results of phase solubility with the binding energy of −4.7 (α-CD), −5.10 (β-CD), and −6.70 (γ-CD) kcal/mol, respectively. The inclusion complex (IC) of G-Re was prepared with γ-CD via the water-stirring method followed by freeze-drying. The successful preparation of IC was confirmed by powder X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). In-vivo absorption studies were carried out by LC-MS/MS. Dissolution rate of G-Re was increased 9.27 times after inclusion, and the peak blood concentration was 2.7-fold higher than that of pure G-Re powder. The relative bioavailability calculated from the ratio of Area under the curve AUC0–∞ of the inclusion to pure G-Re powder was 171%. This study offers the first report that describes G-Re’s inclusion into γ-CD, and explored the inclusion complex’s mechanism at the molecular level. The results indicated that the solubility could be significantly improved as well as the bioavailability, implying γ-CD was a very suitable inclusion host for complex preparation of G-Re.

Purpose. K-wire with tension band (KTB) technique has long been the primary surgical method for transverse patella fractures; however, it also has shortcomings. This study is aimed at evaluating the three different techniques to see whether the cannulated screw tension band (CSTB) or ring pin tension band (RPTB) techniques could decrease complications and achieve better knee function compared with KTB. Methods. We conducted a retrospective comparison of the KTB, CSTB, and RPTB fixation techniques. We selected and reviewed 90 patients (30 patients in each fixation group) with follow-up at least 2 years. Duration of operation, intraoperative blood loss, mean healing time, visual analog scale score, range of motion, Böstman score, Iowa knee score, modified Lysholm rating scale, and postoperative complications were compared. Multivariate analyses were performed to identify the independent risk factors for fracture healing time, postoperative complications, and knee function recovery. Results. After adjusting for confounding factors, multivariate regression analysis revealed that CSTB was 0.26 times (95% CI: 0.08-0.86, p = 0.027 ) less likely to prolong fracture healing time, 0.20 times (95% CI: 0.06-0.64, p = 0.007 ) lesser risk of postoperative complications, and more than four times (95% CI: 1.41-13.56, p = 0.011 ) as likely to improve the knee function score compared with KTB. Besides, RPTB were also superior to KTB in reducing the incidence of postoperative complications (OR: 0.21, 95% CI: 0.07-0.64, p = 0.006 ) and improved knee function score (OR: 3.96, 95% CI: 1.30-12.08, p = 0.016 ); however, the CSTB group being more superior. In addition, AO/OTA C2 fractures (OR, odds ratio: 10.68, 95% CI: 1.30-87.70, p = 0.027 ) and high-energy fracture (OR: 8.78, 95% CI: 1.57-49.17, p = 0.013 ) were also associated with prolonged fracture healing time but not with postoperative complications and knee function. No significant differences in related indicators such as gender, age, BMI, AO/OTA classification, fracture side, injury mechanism, duration of operation, and intraoperative blood loss were detected among the three groups. Conclusion. This study demonstrated that the CSTB technique is superior to KTB and RPTB techniques in reducing the incidence of postoperative complications, and it also has advantages in accelerating fracture healing, achieving better VAS, ROM, and functional recovery. Further long-term large-sized prospective randomized trials are needed to evaluate the efficacy of the KTB in treating transverse patellar fractures.

The excretion of neurotransmitter metabolites in normal individuals is of great significance for health monitoring. A rapid quantitative method was developed with ultra-performance liquid chromatography-tandem mass spectrometry. The method was further applied to determine catecholamine metabolites vanilymandelic acid (VMA), methoxy hydroxyphenyl glycol (MHPG), dihydroxy-phenyl acetic acid (DOPAC), and homovanillic acid (HVA) in the urine. The urine was collected from six healthy volunteers (20-22 years old) for 10 consecutive days. It was precolumn derivatized with dansyl chloride. Subsequently, the sample was analyzed using triple quadrupole mass spectrometry with an electrospray ion in positive and multireaction monitoring modes. The method was sensitive and repeatable with the recoveries 92.7-104.30%, limits of detection (LODs) 0.01-0.05 μg/mL, and coefficients no less than 0.9938. The excretion content of four target compounds in random urine samples was 0.20 ± 0.086 μg/mL (MHPG), 1.27 ± 1.24 μg/mL (VMA), 3.29 ± 1.36 μg/mL (HVA), and 1.13 ± 1.07 μg/mL (DOPAC). In the urine, the content of VMA, the metabolite of norepinephrine and adrenaline, was more than MHPG, and the content of HVA, the metabolite of dopamine, was more than DOPAC. This paper detected the levels of catecholamine metabolites and summarized the characteristics of excretion using random urine samples, which could provide valuable information for clinical practice.

The combustion of double fuel droplets with different initial centre spacings and different droplet radii in convective environment are studied numerically by using the VOF (volume of fluid) model....

A two-fluid three-flow-field model that considered interactions among the droplets, steam and liquid film during dryout evolution in the helically coiled once-through steam generator was introduced to numerically study the distribution of the thermal-hydraulic parameters. Simulation results showed that the slip ratio first increased and then decreased in the flow boiling process. The slip ratio was relatively small due to the secondary flow in the tube, and the maximum value was only 1.065. Because the steam had a relatively strong entrainment effect on the droplets, the frequency of droplets hitting the wall was high, resulting in only a small level of deviation from thermodynamic equilibrium. When dryout occurred, the local wall temperature at different circumferential angles, as well as the average wall temperature, reached a maximum and then decreased. The dryout incipience occurred at a distance of 2.8 m from the inlet of the helically coiled tube. The circumferential angle at the position of dryout incipience was 100–140° while the dryout region at the outlet extended to 70–270°. The circumferential wall temperature was non-uniformly distributed and its maximum value was first increased and then decreased.

Semen raphani (S. raphani) and Panax ginseng (P. ginseng) is one of eighteen counters in Traditional Chinese Medicine (TCM). This study was aimed to investigate the antagonistic effect of S. raphani on P. ginseng. Three extractions were obtained with single P.ginseng extraction (GW), mixture of P.ginseng and S. raphani extraction (GWSW) and co-extraction of P.ginseng and S. raphani (GSW). Saponin were detected and fingerprinted after LC-Q-TOF-MS identification. The effect of three extractions on HPA regulation was evaluated through the indicators of plasma adrenocorticotropic hormone (ACTH) and corticosterone (CORT) in mouse. Results showed that saponin contents in three extractions were 1.236 ± 0.048 mg/mL, 1.220 ± 0.034 mg/mL and 0.966 ± 0.05 mg/mL for GW, GWSW, GSW separately. Twenty-seven saponin monomers were identified in both GW and GWSW while only twenty-four saponin monomers were identified in GSW with saponin monomers decreased on different levels. GW could change levels of CORT and ACTH in quiet and stressed mice (P

Tryptophan (Trp), also known as α-amino β-indolepropionic acid, is an essential amino acid, which is involved in various physiological processes. Studies have shown that tumors, infectious diseases, and neurological diseases are accompanied by Trp-related metabolic disorders. Understanding the excretion of Trp and its metabolites in normal individuals is of great significance for treating Trp-related diseases and monitoring the health. A rapid quantitative method was developed based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Further, this method was applied to the simultaneous determination of Trp and its metabolites, including kynurenine (Kyn), kynurenic acid (KA), 3-hydroxykynurenine (3-OH-Kyn), 3-hydroxyanthranilic acid (3-OH-AA), xanthurenic acid (XA), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA). The excretion and amount of target compounds in random urine samples collected from healthy participants were studied using this method. Urine samples were collected from healthy male volunteers (between 20-22 years old) without any diet and exercise restrictions. Urine samples were collected between 11∶00-13∶00 daily for 10 d. Thereafter, the urine samples were diluted, centrifuged, and subjected to pre-column derivatization with dansyl chloride (DNS-Cl). Caffeic acid (CA) was used as the internal control. Later, the derivatives were detected using triple quadrupole mass spectrometry with electron pray ionization (ESI) in positive and multi reaction monitoring (MRM) modes. The samples were separated using a Thermo C18 column (50 mm×3 mm, 2.7 μm) with 0.1% aqueous formic acid aqueous solution and methanol as mobile phases at a flow rate of 0.2 mL/min. The three most abundant ions for each derivative were selected for downstream analysis, and the internal control was used for quantification. The polarity and molecular weight of the compounds were found to be altered effectively after DNS-Cl derivatization treatment. The dansyl group effectively altered the polarities of the derivatives, such that their retention behaviors in the reverse elution system were similar and they were well separated. The interference due to impurities was effectively eliminated using the MRM mode. The results showed significant linear correlation, since the correlation coefficients were greater than 0.9740. The recoveries were between 93.24%-107.65%, and the LODs were 0.005-0.5 ng/mL for the eight compounds. Trp prototype and the seven target metabolites, including 3-OH-Kyn, 3-OH-AA, XA, Kyn, KA, 5-HIAA, and 5-HT generated through Trp-5-HT and Trp-Kyn pathways were detected in the urine samples. These results indicated that Trp was excreted in a prototypic form or after being metabolized. The level of the target compounds in random urine samples of individuals were 0.99-3.72 (3-OH-Kyn), 2.51-21.11 (3-OH-AA), 0.25-1.12 (XA), 0.15-1.53 (Kyn), 0.24-2.58 (KA), 0-0.31 (5-HT), and 2.2-17.94 (5-HIAA) μg/mL. For the same individual, in the state of physical health, the fluctuations of Trp and its metabolites in urine were large. Due to these large fluctuations in the absolute content, the difference between individuals was not significant. The data generated using 70 urine samples revealed that the amount of excreted Trp being metabolized was 124%-268% of prototype, which further indicated that the excretion after metabolism was the major underlying mechanism. Upon comparing the levels of metabolites in the Trp-5-HT and Trp-Kyn pathways, the results indicated that the levels of 3-OH-AA and 3-OH-Kyn generated upon Trp degradation through the Kyn pathway was higher than those of the other products. Trp was degraded via Kyn pathway to produce 3-OH-AA, which was the main metabolite of Trp found to be present in the body. This manuscript detected the levels of Trp and its metabolites, as well as summarized the characteristics of excretion using random urine samples, which could provide valuable information for clinical practice.

Objectives: To study the anatomy of the dorsal metacarpal arteries and their branches, to understand the positions and shapes of the arteries and their branches, and to observe the capillary network formed on the lateral and the dorsal sides of the finger under a microscope. Based on this anatomy, a finger fascia pedicled skin artery branch flap was designed to repair fingertip wounds. Methods: A total of 5 fresh adult cadaveric hand specimens were infused with red latex. The anatomy of the dorsal finger intrinsic arteries of the 40 fingers (excluding the thumbs) were observed under a microscope, and a capillary network was formed on the lateral and the dorsal sides of the fingers. Then, 10 cases of finger soft tissue defects were repaired using an anatomy-based design finger fascia pedicled skin artery branch flap. Results: The anatomical observations indicated that the intrinsic artery on each side of the finger sends four thicker cutaneous branches toward to the dorsal side, wherein the descending branch of the upper cutaneous branch coincides with the ascending branch of the next cutaneous branch to form a lateral vascular chain. A fascia flap pedicled (>0.5 cm) skin artery branch flap was used to repair the patients’ finger injuries (8 males and 2 females, aged 21 to 52 years). The wound surface ranges were about 2.8 cm × 1.9, and the flap ranges were about 3 cm × 2.1 cm. During the 5-12 months of follow-up, all the flaps survived well. Conclusion: The bilateral finger arteries emit a number of macroscopically identifiable capillary branches and form a capillary network using anastomosis between the cutaneous branches. The finger fascia pedicled skin artery branches flap, not

Considering the tube support plates installed among the tube bundle of actual once-through steam generator, the mathematical model suitable for smooth channel was modified to numerically simulate the two-phase flow and heat transfer and dryout under three structures (no tube support plates, tube support plates with and without gaps). The results show that the slip ratio increases rapidly when fluid flows through the tube support plates, and then decreases rapidly under the strong disturbance caused by the turbulence transition at the downstream position of tube support plates. The maximum slip ratio for the case of TSPs with gaps is lower than that for the other two cases, which is conducive to prevent interphase slipping. The turbulence transition and great steam quality caused by heat transfer enhancement at the downstream position of tube support plates both have positive effects on tearing the annular liquid film, resulting in the dryout position being at the upstream position of that for the case of no tube support plates. The damage of dryout deterioration can be relieved significantly when considering tube support plates, and the corresponding rising amplitude of wall temperature at dryout position reduces from 300 K for the case of no tube support plates to 200 K. With the development of flow and heat transfer, the non-uniform levels of circumferential wall temperature for the cases of tube support plates with and without gaps show completely opposite trends.

Numerical simulation is carried out for nucleate boiling heat transfer of a helically coiled tube. The boiling heat transfer characteristics and the non-uniform wall temperature distribution are in basically consistent with existing experimental data. The influences of operating conditions and shapes on wall temperature are discussed in detail. The results show that the liquid gathers at the outside and the bottom of the cross section during nucleate boiling heat transfer, resulting in a lower wall temperature in these locations. However, the movement of the vapor phase to the top and the inside walls results in higher local wall temperatures. The maximum temperature difference throughout the cross section is approximately 10 K. Furthermore, the distribution of vapor volume fraction becomes uniform as the secondary flow enhances. Due to the vapor–liquid phase distribution, the wall temperature of the cross section shows a sharp rise before decreasing. Under different experimental conditions, the position of the maximum wall temperature changes from 90° to 180° and the maximum deviation is more than 60°.

The safety of boilers is directly related to the operation of steam power plants. Consequently, accurate short-term forecasting model is needed for the robust control of important safety performance parameters. In this study, an advanced data-driven modelling framework based on neural networks is proposed to establish short-term forecasting (STF) models for three safety indicators of a supercharged boiler: main steam temperature (MST), drum pressure (DP) and drum level (DL). To overcome the challenges of external noise and non-stationarity, locally weighted regression (LWR) and differencing method are introduced to improve the model performance. Convolutional neural network (CNN) and long short-term memory network (LSTM) are proved as practical options for STF modelling, while CNN has a lower computational cost. The models show excellent performance on a real dataset containing multiple dynamic processes: the mean absolute percentage errors of the three targets are 0.0041%, 0.0355% and 0.0221% respectively and the forecasting horizon is future 60 timesteps. The sensitivity of STF models to outliers is analyzed. The results show that the models are not sensitive to eroded input. The proposed framework and methods can be a preferential solution to the forecasting modelling of power systems.

Data security and privacy protection in the Internet of Things (IoT) have attracted wide attention, especially in private scenarios, such as Home Internet of Things (HIoT). Data de-centralization and mature encryption technology based on blockchain technology provide a proper security guarantee for HIoT. However, common blockchain technology consensus algorithm consumes a lot of computing resources of devices, and it is easy to cause network congestion in LAN due to the size of each transaction and transactions' frequently spread. Just Blockchain Storage Model (JBSM) means every blockchain node in the network stores all of the transaction data that launched in the whole blockchain network, there is no doubt that JBSM consumes a lot of storage resources. In this paper, we propose a Blockchain and Centralized Storage Model (BCSM) for HIoT, which reduces the network bandwidth occupied by transaction data and increases the speed of transaction verification by reducing the size of transaction data. The model consists of three parts: HIoT, Blockchain Network and Cloud Storage Server. This paper analyses how BCSM improves transaction efficiency. Finally, through the simulation experiment on Tencent BaaS, the model is compared with the JBSM, which shows the method in this paper not only has the data security characteristic endowed by the blockchain but also improves the transaction efficiency to a certain extent.

Purpose This study was intended to characterize the epidemiological features of thumb polydactyly (TP) in South China. Methods Clinical records were retrieved from 1 central hospital in South China to identify the patients with a definite diagnosis of TP from January 2004 to January 2017. The cases were classified by their x-ray appearance. The data collected included sex, age at first operation, reoperation, family history, unilateral/bilateral polydactyly, right/left hand involvement in unilateral cases, classification of polydactyly, and the presence of associated congenital anomalies. Results A total of 428 patients with a definite diagnosis of TP were identified (278 males and 150 females) involving 483 cases, 373 unilateral and 55 bilateral. A syndrome or associated congenital anomaly was found in 26 (18 unilateral and 8 bilateral cases). A dominant thumb, larger and more developed, was observed in 448 hands (93%), and was the ulnar thumb in 433. Owing to postoperative complications, 31 thumbs (6.4%) underwent reoperation. The average interval from initial surgery to reoperation was 4.8 years. Conclusions Thumb polydactyly had a male predominance in this Chinese cohort, mostly occurring on the right hand with an ulnar dominant thumb. Bilateral cases had a higher incidence of associated anomaly and positive family history than unilateral cases. The need for additional surgery for TP might occur as late as 4.8 years after primary surgery. Type of study/level of evidence Therapeutic IV.

The two-fluid three-flow field mathematical model is used to carry out the numerical simulation of heat transfer characteristics of steam-liquid two-phase flow in dryout and post-dryout region of the rifled tube. The absolute vorticity flux and intensity of the secondary flow are introduced to quantitatively characterize the heat transfer enhancement. The results show that, compared with smooth tube, the rifled tube can greatly reduce the rise of wall temperature and have a significant effect on dryout inhibition. The cross-section wall temperature of rifled tube presents a periodic distribution. The wall temperature at the intersection of the root and rib side is higher due to the fluid retention. After the dryout occurs, the wall temperature is higher than other locations due to the continuous liquid film on the crest being torn. The secondary flow strength and heat transfer enhancement degree of fluid in rifled tube increase with the increase in axial height. The absolute vortex flux, intensity of the secondary flow and absolute value of the vorticity in main flow direction can reflect the degree of fluid disturbance caused by internal thread.

Taking a T300k VLCC oil tanker as the research object, the ship route estimation model with minimum fuel consumption, CO2 emissions and shortest ETA as the objective function is established, which considers the weather conditions and constraints of the main engine rated power and safety comprehensively. On the basis of model verification, combined with the weather forecast data and the current maritime market conditions, the estimation indicators were analyzed. The research results show that, prefabricated Route 1 and 2 were the shortest ETA and the minimum fuel consumption routes respectively, although the prefabricated Route 1 saved 36.58 h compared with the prefabricated Route 2, the fuel consumption and CO2 emissions of the prefabricated Route 2 were reduced by 0.94 t/h and 2.92 t/h, and under the shortest ETA objective function, if keeping the initial speed, the main engine would be limited by rated power when the ship encounters Beaufort number≥4 headwind or bow wind. Accordingly, the ship route estimation method comprehensively considering weather conditions and constraints can analyze the variation rules of the fuel consumption, speed loss, CO2 emissions and costs of multiple prefabricated routes under different objective functions, which can provide decision support for shipping companies to improve operation economy.

A three-dimensional “unit tube” physical model is established by simplifying the once-through steam generator (OTSG) designed by B&W and a three-dimensional two-fluid three-flow-field mathematical model that takes into account the interactions between liquid droplets and other flow-fields (steam and liquid film) and the interactions between liquid droplets and the wall in liquid deficient regions is introduced. The results of a numerical simulation using the developed OSTG model conducted at different operating parameters show that the three-dimensional two-fluid three-flow-field mathematical model used in this paper can accurately predict the dryout and post-dryout wall temperature distribution of the OTSG at different operating conditions. The simulations also show that the post-dryout wall temperature decreases along the height of the heat transfer tube at low mass fluxes while gradually increases at high mass fluxes, which is opposite to the changes in wall temperature seen in post-departure from the nucleate boiling region. Furthermore, dryout occurs later as pressure increases, with a smaller soaring maximum of the wall temperature. Dryout will occur when the wall temperature gradient reaches or exceeds 250 K/m as the heat flux increases.

Accurately predicting dryout and post-dryout heat transfer characteristics is critical for proper design of once-through steam generators. This paper provides a reasonable and simple method for this prediction by introducing a two-fluid, three-flow-field mathematical model and improving the dryout criterion-critical quality, and conducts a numerical simulation of dryout and post-dryout heat transfer in a once-through steam generator to prove the model’s performance. The results show that the critical quality in a once-through steam generator is about 0.82, with the heat transfer capacity significantly reducing and the wall temperature sharply increasing in a non-linear form by approximately 30 K when dryout occurs. Part of the steam is superheated in the post-dryout region, resulting in a deviation from thermodynamic equilibrium between the vapor and liquid phases. Dryout and post-dryout heat transfer in the once-through steam generator operate between complete deviation from thermodynamic equilibrium and complete thermodynamic equilibrium. Therefore, the presence of droplets has a significant influence on the mass, momentum and energy transfer between the film and vapor phases.

Supercharged boilers are widely used as the core equipment of ship steam-power plants. A 1:1 model is built considering the connection details of tube-tubesheet joints. Furthermore, numerical simulation of stress field and fatigue life based on the DBA method is conducted. The results show that the maximum equivalent stress amplitude of 253.81 MPa appears on the tube-tubesheet joint of the tube plant radiation area. The total stress amplitude is dominated by the thermal stress range. The last calculated permissible number of cycles based on the fourth strength theory is 161,744 times, which is 15.7% higher than the result calculated by the third strength theory.

A non-equilibrium thermodynamic model for a steam catapult’s steam accumulator is established based on the mass and energy conservation of steam and water by introducing an evaporation (condensation) relaxation time. The accuracy of the model is validated through testing with a lab-based steam accumulator system, which is also used to determine the key coefficients for the mathematical model. The influence of key parameters on the charging performance of the steam accumulator is investigated using potential theory and a mechanism analysis of the non-equilibrium thermodynamic process of the steam accumulator. The results show that the charging time decreases as the charging energy per unit time increases, meanwhile the pressure drop ratio caused by the non-equilibrium thermodynamic process increases as increase of the charging energy per unit time. Furthermore, the main driving force of the macroscopic non-equilibrium thermodynamic process of a steam accumulator is the energy potential difference between the current and the saturated state, increasing the water filling coefficient of the steam accumulator improves its energy storage, but has a negative impact on the cycle time of the system. Finally, the charged steam flow has a stronger influence on the water temperature distribution of the steam catapult’s steam accumulator than the steam enthalpy, and plays a leading role when the charging energy per unit time is constant.

Using the steam generator of Daya Bay nuclear power plant as prototype, a one-dimensional dynamic mathematical model of nuclear-powered steam generator is built addressing the primary side fluid, the secondary side fluid and the inner and outer walls of the u-tubes based on distributed parameter method and reasonable assumptions. A dynamic simulation program is developed based on MATLAB using Runge–Kutta method and dynamic heat transfer performance simulation of steam generator is conducted under varying power. The calculation results show that the outlet temperature of primary side, the vapor saturation temperature and the mass fraction of secondary side agree with actual operating data of Daya Bay Nuclear Power Plant. Outer wall temperature at interface between parallel flow preheating-section and boiling-section is the highest. It provides a theoretical basis for the analysis of steam generator actual operating condition to build a one-dimensional mathematical model of steam generator based on the distributed parameter method and apply in simulation successfully.

1-acryloylpyrrolidine-2-carboxylic acid (APCA) monomer was copolymerized with acrylonitrile (AN) by aqueous suspension polymerization. High molecular weight (HMW) copolymers of AN and APCA [poly(AN-co-APCA)] with different copolymer composition were successfully prepared by employing azobisisobutyronitrile (AIBN) as initiator and polyvinyl alcohol (PVA) as dispersant in a H2O/N,N-dimethylformamide (DMF) mixture at 60°C. The PAN homopolymer and copolymers were characterized by elemental analysis (EA), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The EA results indicated that the content of oxygen increased significantly in PAN copolymers with increasing APCA content. The APCA copolymer composition calculated from the EA was higher than that from 1H NMR spectra. The FTIR spectra of PAN and poly(AN-co-APCA) with different monomer ratios confirmed that the contents of APCA units in the copolymer chains i...

Aim. To evaluate the possible association between the vitamin D receptor (VDR), single-nucleotide polymorphisms (SNPs), and hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV) infection.Method. 968 chronic HBV infection patients were enrolled, of which 436 patients were diagnosed HCC patients, and 532 were non-HCC patients. The clinicopathological characteristics of HCC were evaluated. The genotypes of VDR gene at FokI, BsmI, ApaI, and TaqI were determined.Results. The genotype frequencies of VDR FokI C>T polymorphism were significantly different between HCC and non-HCC groups. HCC patients had a higher prevalence of FokI TT genotype than non-HCC subjects. With FokI CC as reference, the TT carriage had a significantly higher risk for development of HCC after adjustments with age, sex, HBV infection time,α-fetoprotein, smoking status, and alcohol intake. In addition, we also found that the TT genotype carriage of FokI polymorphisms were associated with advanced tumor stage, presence of cirrhosis, and lymph node metastasis. The SNP at BsmI, ApaI, and TaqI did not show positive association with the risk and clinicopathological features of HCC.Conclusion. The FokI C>T polymorphisms may be used as a molecular marker to predict the risk and to evaluate the disease severity of HCC in those infected with HBV.

Xing Yao,1,* Xiang Wang,1,* Zishu Wang,2,* Licheng Dai,1 Guolei Zhang,1 Qiang Yan,1 Weimin Zhou11Huzhou Central Hospital, Zhejiang Huzhou, 2Department of Medical Oncology, First Affiliated Hospital, Bengbu Medical College, Anhui, People’s Republic of China *These authors contributed equally to this workBackground: The aim of this study was to examine the patterns of expression of epithelial-mesenchymal transition (EMT)-related proteins in intrahepatic cholangiocarcinoma. The clinicopathological and prognostic value of these markers was also evaluated.Methods: We detected the expression status of three EMT-related proteins, ie, E-cadherin, vimentin, and N-cadherin, by immunohistochemistry in consecutive intrahepatic cholangiocarcinoma specimens from 96 patients.Results: The frequency of loss of the epithelial marker E-cadherin, and acquisition of mesenchymal markers, vimentin and N-cadherin, in intrahepatic cholangiocarcinoma was 43.8%, 37.5% and 57.3%, respectively. Altered expression of EMT markers was associated with aggressive tumor behavior, including lymph node metastasis, undifferentiated-type histology, advanced tumor stage, venous invasion, and shorter overall survival. Moreover, loss of E-cadherin was retained as an independent prognostic factor for patients with intrahepatic cholangiocarcinoma in multivariate analysis.Conclusion: Our results suggest that the EMT process is associated with tumor progression and a poor outcome in patients with intrahepatic cholangiocarcinoma, and inhibition of EMT might offer novel promising molecular targets for the treatment of affected patients.Keywords: intrahepatic cholangiocarcinoma, epithelial-mesenchymal transition, expression, prognosis, immunohistochemistry