Search

• Staged autotransfusion during ECMO decannulation effectively maintains Hb levels. • This approach reduces allogeneic RBC transfusion needs and lowers transfusion cost. • No significant differences in adverse events between groups. • No significant differences in decannulation success rates between groups. Clinical blood resources are scarce and autologous blood transfusion for extracorporeal membrane oxygenation (ECMO) withdrawal is less studied. To assess the use of staged autotransfusion during ECMO decannulation. The study included ECMO withdrawal patients. Patients in the autologous transfusion group underwent staged transfusion during ECMO withdrawal, while those in the control group received 2.0 units of allogeneic packed red blood cells (RBCs) to increase hemoglobin (Hb). Parameters such as Hb, hematocrit (Hct), adverse events, decannulation success rate, volume of allogeneic RBC transfusions, and transfusion costs were compared. A total of 82 Chinese patients were enrolled, with a mean age of 46 years, 27 were female, and the top three primary diagnoses were cardiac arrest, acute myocarditis, and severe pneumonia. There were 41 individuals in the autologous blood transfusion group and 41 in the control group. No significant differences were observed in Hb, Hct, adverse events, and the success rate for decannulation between the two groups (all P > 0.05). Compared with the control group, the volume of allogeneic RBC transfusions [0 (0∼1.50) U vs. 3.5 (1.88∼40) U, P < 0.001] and the total cost [130 (130∼390) Chinese Yuan (CNY) vs. 910 (487.50, 1040) CNY, P = 0.002] were lower in the autologous transfusion group. In comparison with allogeneic RBC transfusion, staged autotransfusion during ECMO decannulation not only effectively maintained Hb levels but also reduced the requirement for allogeneic RBC transfusions. In addition, this approach decreased the associated costs and did not increase the risk of clinical adverse events. [ABSTRACT FROM AUTHOR]

• The proposed model only places the PD subdomain in the crack initiation region of porous material, which greatly improves the computational efficiency while ensuring the calculation accuracy. • The displacement vector and mass matrix are reconfigured to ensure the calculation consistency in the process of adaptive expansion of the PD subdomains. • The fracture phenomenon of porous materials based on this model is well reproduced and interesting results are obtained. Predicting the dynamic failure process of porous materials is a challenging task due to their complex structure. To minimize the use of time-consuming peridynamic (PD) models and to avoid surface effect issues in the dynamic failure of complex porous materials, this paper proposes a strength-induced PD model. The paper first presents the dynamic formula and relevant finite element discrete equation of the coupled PD and classical continuum mechanics (PD-CCM) model based on the Morphing method. The Morphing function is implemented to control the material parameters and enable the free transformation of PD and CCM models. Based on the coupled PD-CCM model, the strength-induced PD model is established to adaptively expand the PD subdomain in porous materials by controlling the Morphing function value through the strength state of the structure. This model enables the PD subdomain to appear automatically when the porous materials reach the critical stress state. The proposed model accurately predicts the location of crack initiation and path while minimizing computational costs and improving efficiency. Three two-dimensional numerical examples are used to verify the effectiveness, efficiency, and accuracy of the model. The results of the simulation suggest that the location where the crack initiates in the porous materials is strongly influenced by the amplitude of the dynamic load. Cracking is dependent on the pores and typically occurs through them. [ABSTRACT FROM AUTHOR]

The prevalence of pesticide usage has brought the matter of pesticide residues to the forefront, necessitating the development of effective detection methods as a crucial step towards addressing this issue. This study presents a novel approach for detecting pesticide residues in vegetables using glass slide-formula-ion mobility spectrometry (IMS). The approach enables swift analysis of 36 different pesticides across three vegetable species with glass slides. To establish a formula for calculating pesticide residues in vegetables using glass slides, the vegetable samples and glass slides were placed in a spray tower and evenly sprayed pesticides. The per unit area of glass slides was used to calculate the pesticide loading capacity and total pesticide loading area of vegetables. The original residues were analyzed with ultra high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The field experiment yielded consistent results between the model values of the formula and the actual measured values, with correlation coefficients (R2) ranging from 0.927 to 0.983. The slide-formula model-IMS method was found to be effective for field applications, as it proved to be simple, rapid, and accurate in predicting pesticide residue concentrations in vegetable samples. This approach could be a valuable tool for monitoring pesticide residues in vegetable cultivation globally. [Display omitted] • A medium for the determination of pesticide residues in vegetables was developed. • Rapid pretreatment of glass slides greatly reduces matrix and impurity interference. • Relationship between initial pesticide residues in crop and medium were clarified. • Modelling relationship and verify it effectiveness by field trials. • Rapid detection analysis combined with ion mobility spectrometry. [ABSTRACT FROM AUTHOR]

• A new viscoelastic bond-based peridynamic model (VBPD) is developed to describe the dynamic failure of quasi-brittle materials. • The adaptive coupling of peridynamics and the classical continuum mechanics (PD-CCM) model established by the Morphing method to simulate the failure process of quasi-brittle materials. • Based on this model, the whipping effect of concrete dam under explosion load is found. A new viscoelastic bond-based peridynamic model (VBPD) is developed to describe the nonlinear deformation and dynamic failure of quasi-brittle materials under different loading rates. This model is established on the viscoelastic constitutive equation of classical continuum mechanics, which involves damage and strain rate effects. The model superbly generalizes the definition of strain rate in classical continuum mechanics phenomenally to the bond stretch rate in the bond-based peridynamics under one-dimensional strong impact loads. To describe the progressive damage of the peridynamic bond, The scalar value function related to bond stretch and bond stretch rate is introduced in the model to define the deformation of the peridynamic bond. Moreover, the model also considers the history of bond force under cyclic load. To improve the computational efficiency of simulation, the adaptive coupling of peridynamics and the classical continuum mechanics (PD-CCM) model established by the Morphing method is used to simulate the failure process of quasi-brittle materials. By combining the VBPD model and the PD-CCM model, the VBPD model is utilized to simulate the deformation and failure process of quasi-brittle materials under dynamic load with the least peridynamic subdomain. Finally, the validity of the proposed model is verified by three two-dimensional numerical examples. [ABSTRACT FROM AUTHOR]

• The structural performance of G550 high strength CFS lipped channel section columns was studied. • 10 axial compression tests on G550 high strength CFS lipped channel section columns were conducted. • FE models were developed and validated against test results and then used to perform parametric studies. • The current design methods were evaluated for their applicability to G550 high strength CFS lipped channel section columns. This paper presents the experimental and numerical investigations into the structural performance and strengths of G550 high strength cold-formed steel (CFS) lipped channel section columns failing by interactive buckling. A testing program was first conducted, comprising material testing, measurements of initial local, distortional and global geometric imperfections and ten pin-ended column tests. The interaction between different buckling modes was observed and discussed for all the examined specimens upon testing. A numerical modeling program was subsequently performed, where numerical models were created and verified with reference to the test results and afterwards utilized to conduct parametric analysis to produce more numerical data over an extensive spectrum of cross-section geometries and effective member lengths. The effective width method (EWM) codified in the European code and direct strength method (DSM) specified in American and Australian standards were evaluated, based on the combined set of numerical and test data, for their suitability to G550 high strength CFS lipped channel section columns susceptible to interactive buckling. The evaluation results indicated that (i) the EWM yielded scattered and conservative ultimate strengths for columns with small and intermediate slenderness ratios, but relatively accurate results for those of large slenderness ratios and (ii) the DSM led to more consistent and accurate strength predictions for G550 high strength CFS lipped channel section columns failing by interactive buckling, though a number of strength predictions were on the unsafe side. [ABSTRACT FROM AUTHOR]

Highlights • Pipe orientation effect on average void fraction is investigated. • The distribution parameter and drift velocity in an inclined pipe are studied. • A new void fraction correlation including the effect of pipe orientation is developed based on drift flux model. Abstract Experimental study on steam-water two phase vertical and inclined upward flow (15–90°) was performed in a rectangular channel with cross section of 17 mm × 10 mm under atmospheric pressure to investigate the phase distribution and the average void fraction in the cross section which were obtained from the local void fraction measurement by a conductivity probe. The inlet superficial velocities of the steam and water varied from 0.72 to 3.85 m/s and from 0.11 to 0.3 m/s respectively. A high speed camera was used to identify the flow patterns. Experimental results show that the phase distribution curves are significantly affected by channel orientation and the average void fraction first decreases and then increases with the increase of orientation. Based on the drift-flux model, two parameters, namely, the distribution parameter (C 0) and the drift velocity (U gm ) have been studied in detail. Both the distribution parameter and the drift velocity are found to be functions of orientation. The distribution parameter decreases with the increase of orientation while the drift velocity first increases and then decreases with the increase of orientation., Based on the experimental data, an improved drift-flux model is proposed especially for the slug and churn flow, which predicts the void fraction in an inclined channel with good accuracy. [ABSTRACT FROM AUTHOR]

Methamphetamine (METH) is a commonly abused psychostimulant that can induce severe neurotoxicity. Cardiovascular injury caused by METH has recently gained increasing attention; however, the underlying mechanisms remain unclear. As autophagy has been shown to be associated with cell injury, the association between autophagy and METH-mediated cell apoptosis was investigated in the present study. METH treatment significantly increased the expression of two key autophagy proteins, i.e., Beclin-1 and LC3-II, in the cardiomyocyte cell line H9C2. Furthermore, according to western blot and flow cytometry analyses, METH contributed to cell injury and markedly enhanced cleaved-caspase 3 and PARP expression. In addition, the corresponding AKT-mTOR survival pathway axis was appeared deactivated. The autophagic activity was closely associated with METH-mediated cell injury because rapamycin, which is an autophagy inducer, markedly attenuated METH-induced cell injury, while 3-Methyladenine (3-MA), which is an autophagy inhibitor, and bafilomycinA1 (Baf-A1), which is a blocker of autophagosome-lysosome fusion, markedly exacerbated METH-induced cell injury. Notably, defective autophagosome-lysosome fusion might be partially involved in the METH-induced enhancement of LC3-II expression and cell injury. However, the underlying mechanisms require further investigation. [ABSTRACT FROM AUTHOR]

External reactor vessel cooling (ERVC) is the key technology for In-Vessel Retention (IVR) to ensure the safety of a nuclear power plant (NPP) under severe accident conditions. The thermal margin of nucleate boiling heat transfer on the reactor pressure vessel (RPV) lower head is important for ERVC and of wide concern to researchers. In such boiling heat transfer processes, the reactor vessel wall inclination effect on the heat transfer coefficient (HTC) and critical heat flux (CHF) should be considered. In this study, experiments were performed to investigate the effects of surface orientation and heater material on the HTC and CHF of nucleate boiling. Copper (Cu), stainless steel (SS) as well as prototype material (SA508) of the reactor pressure vessel in the nuclear power plant were used to perform boiling tests under atmosphere pressure, respectively. The orientation angle of all boiling surfaces were varied between 0° (upward) and 180° (downward). The experimental results show that the HTC is enhanced for the downward heater surfaces ( φ > 90 ° ) under the low heat flux conditions and the enhancement ratio decreases with the increase of the heat flux. In addition, the relationship of measured CHF value with the orientation angle was obtained and it shows that the CHF value changes little as the inclination angle increases from 0° to 120°, but it decreases rapidly as the orientation angle increases towards 180° for all boiling surfaces. The material effect, which indicated by thermal effusivity ρ c p k , on CHF is also investigated that the surface with larger thermal effusivity has the higher CHF value. In addition, the SA508 surface has the highest CHF value comparing with those of Cu surface and SS surface due to surface corrosion in the boiling process. Based on the experimental data, a correlation for CHF prediction is developed which includes the effects of surface orientation, thermal effusivity and corrosion. [ABSTRACT FROM AUTHOR]

As the last stage of a moisture separator, the drain device is an important part of the secondary separator which can affect the separation efficiency. The emphasis of this paper is placed on studying the flow structure and predicting the free liquid surface height in the drain device. Four different turbulence models including k - ε , k - ω , Shear Stress Transport (SST) and Scale-Adaptive Simulation (SAS-SST) were used to simulate the drainage process with air-water mixture (cold state) under ambient temperature and atmosphere pressure. These models were validated by the experimental data obtained in our previous study. Simulation results showed that the free liquid surface height predicted by the SAS-SST model is in best agreement with the experimental results under cold state. Therefore it was further used to perform the simulation for steam-water mixture (hot state) under the standard working condition (138.1 m 3 /h, 7 MPa and 285.8 °C). The maximum free liquid surface height is simulated to be 269.3 mm for the hot state by the SAS-SST model which is 4.5% higher than that of the cold state. However, it could also meet the design object. [ABSTRACT FROM AUTHOR]

Direct or indirect damage to the nervous system (such as inflammation or tumor invasion) can lead to dysfunction and pain. The generation of pain is mainly reflected in the activation of glial cells and the abnormal discharge of sensory neurons, which transmit stronger sensory information to the center. P2Y12 receptor plays important roles in physiological and pathophysiological processes including inflammation and pain. P2Y12 receptor involved in the occurrence of pain as a sensory information mediator, which enhances the activation of microglia and the synaptic plasticity of primary sensory neurons, and reaches the higher center through the ascending conduction pathway (mainly spinothalamic tract) to produce pain. While the application of P2Y12 receptor antagonists (PBS-0739, AR-C69931MX and MRS2359) have better antagonistic activity and produce analgesic pharmacological properties. Therefore, in this article, we discussed the role of the P2Y12 receptor in different chronic pains and its use as a pharmacological target for pain relief. [ABSTRACT FROM AUTHOR]

Building envelope dampness exposure is correlated with children's respiratory and allergic diseases. However, little research has compared the variation in the health impact of dampness exposure across multiple cities from a longitudinal perspective. A cross-sectional survey and a repeated one were conducted in children's residences in six cities: Chongqing, Shanghai, Nanjing, Wuhan, Changsha and Taiyuan, China, in 2010 (Phase I) and 2019 (Phase II). We selected 17,810 preschoolers during Phase I and 26,001 preschoolers during Phase II aged 3–6 years without changing residence since birth in the study. The proportion of residences with building envelope dampness exposure and the prevalence of respiratory and allergic diseases, except allergic rhinitis, in preschoolers significantly declined from Phase I to Phase II. Dampness exposure increased the risk for most childhood respiratory diseases in Phase II, with a 34% greater risk of lifetime-ever asthma in early residences and a 36% greater risk of current eczema in current residences. Most diseases showed a significantly positive exposure-response relationship to the cumulative period of building envelope dampness exposure (p < 0.05). The risk of developing current eczema was approximately 1.35 and 1.73 times higher in children exposed to both early and current dampness in Phase I and Phase II, respectively, than in children who had never been exposed. These findings provide new insights into the respiratory and allergic diseases in Chinese preschoolers because of building envelope dampness exposure over the last decade. The increased risk in Phase II raises concerns about the household's dampness environment. [Display omitted] • Building envelope dampness exposure has decreased over the last decade. • Prevalence of childhood respiratory diseases has declined over the last decade. • The risk of dampness exposure on respiratory diseases has increased in 2019. • Accumulated dampness exposure has a higher risk of current eczema in 2019. [ABSTRACT FROM AUTHOR]

A fiber-reinforced polymer (FRP)-interlayer-steel confined concrete (FISC) column is formed by bonding the FRP material and a concrete-filled steel tube (CFST) with the grouting material, and it can improve the corrosion resistance and bearing capacity of CFST columns and avoid the early cracking of the epoxy resin in FRP confined concrete-filled steel tubes (CCFT). However, there are few researches on the compressive behaviours of FISC columns and the dual confinement on core concrete from the FRP tube and steel tube has not been expounded clearly. In this paper, twelve FISC specimens were tested under axial compression. The ratio of FRP and steel confining indexes and the concrete strength were the main parameters and the loading conditions (core CFST loading and whole section loading) were included. Failure patterns, load–axial shortening curves, and the strain development were analysed. In addition, the confining stresses of the FRP tube and steel tube were obtained, and it was found that the confinement on concrete could be divided into three stages of the non-confinement stage, the steel-controlling stage, and the FRP-controlling stage. In the FRP-controlling stage, the FRP confining pressure increased at a constant growth rate while the steel confinement was gradually weakened owning to the restraints of the interlayer grouting material. Furthermore, by regarding the concrete and grouting material as a whole unity, the axial stress-strain model of the confined concrete-grouting was developed, and the proposed model can predict the compressive stress-strain behaviours of an FISC column with good accuracy and simplicity. • The dual-confinement mechanism of FRP and steel tubes was revealed. • The effects of FRP-steel confining ratio and concrete strength were discussed. • An axial stress-strain model of confined concrete-grouting was proposed. [ABSTRACT FROM AUTHOR]

This study evaluates the performance of drain device of a steam dryer in steam generator for PWR through experiments with water and air under ambient temperature and pressure. Two different test sections are designed and tested, one of which is equipped with a single drain pipe (test section I) and the other is equipped with double drain pipes (test section II). For the test section I, various slopes of bottom plate (3.5°–5°) and different numbers of water entrance holes (36–136) are investigated to study their effects on drainage performance of the drain device. For the test section II, only the influence of different entrance holes is studied. In experiments, flow fields in the drain device for different flow rates ranging form 13.8 m 3 /h to 165.7 m 3 /h are recorded using a video camera and the corresponding video images are processed by MATLAB to obtain the free liquid surface configuration. The experimental results show that the free liquid surface height of the test section I with single drain pipe is much bigger than that of the test section II with double drain pipes. In addition, the maximum free liquid surface height in the drain tank increases linearly with the increase of flow rate for both test sections while the number of entrance holes has no obvious effect on the maximum free liquid surface height. For the test section I, the bottom plate inclination influences the maximum free liquid surface height and 4° inclination meets the optimized value. [ABSTRACT FROM AUTHOR]

Background and Aims Leptin is an adipokine that has several effects on metabolism and immune system in patients with ankylosing spondylitis (AS). The present investigations of the relationship between plasma/serum leptin levels and AS are contradictory. To derive a more precise estimation on the plasma/serum leptin levels in AS patients and related factors, a meta-analysis was performed. Methods Published literature that compares plasma/serum leptin levels between AS group and control group from PubMed, Embase, Cochrane Library and other databases were searched. The study quality was assessed by the Newcastle–Ottawa scale. Pooled standardized mean difference (SMD) with its 95% confidence interval (CI) was calculated by fixed-effects or random-effect model analyses. Statistical heterogeneity within studies was examined by the Q statistic. Results A total of eight studies including 391 AS patients and 293 healthy controls were finally included in the meta-analysis. No significant differences in plasma/serum leptin levels was found between AS patients and healthy controls when all studies were pooled into the meta-analysis (pooled SMD = 0.384, 95% CI = −1.522 to 0.753). Meanwhile, subgroup analyses by gender also showed no significant differences in plasma/serum leptin levels between case group and controls. Conclusion There is no significant difference in plasma/serum leptin levels between AS patients and controls. [ABSTRACT FROM AUTHOR]

• Probabilistic prediction of concrete-steel (CS) bond strength under high temperature is achieved via Natural gradient boosting. • 267 CS pull-out test samples were gathered to train a prediction model and the model reaches an accuracy of 97%. • The representative deterministic machine learning algorithms and empirical formulas are adopted for comparison. • The mechanism behind the proposed model is explored to prove its rationality and feasibility by Shapley values. The interface bond performance between concrete and steel bars under high temperature has a crucial influence on the fire resistance design of the reinforced concrete (RC) structure, but there is no unified model for the prediction of the bond strength yet. Previous experimental studies have conducted plenty of RC member pull-out tests under high temperature, which could be collected as a comprehensive database. As a data-driven method, machine learning (ML) can efficiently establish the regression relationship between input features and output directly through the data. However, current studies usually use classic ML algorithms for establishing a deterministic prediction model, where only one scalar prediction would be provided and its confidence level is uncertain, which is not instructive for the users. Thus, based on previous experimental data, this paper uses the Natural Gradient Boosting (NGBoost) algorithm to establish a unified probabilistic prediction model for the bond strength between steel bars and concrete under high temperature, considering several key factors, such as fiber fraction, concrete compressive strength, bond strength under room temperature et al. By training on the collected 267 experimental data, the prediction results of the ML based model show that these models attain higher accuracy than those of empirical formulas, and the NGBoost based probabilistic prediction model has better prediction performance than the general deterministic ML models. Finally, the Shapley value method is used to explain the calculation results of the model, and compared with the statistical results such as variance and mean of the calculation results of the five empirical formulas, ML has obvious advantages. [ABSTRACT FROM AUTHOR]

• The mechanisms of failure of the concrete target under penetration is analyzed. • The scaling issue of the resistant stress of concrete target is investigated. • The formula of the resistance with size effect is restructured. This paper presents a comprehensive analysis of the scaling issue for the penetration problem of concrete target impacted by a rigid projectile. The mechanisms of failure and comminution are proposed for the analysis of resistant stress of the concrete target. By introducing the fractal theory for the comminution, the formula of quasi-static resistant stress is derived. The fracture energy and the scaling term are well included in the derived formula without further empirical assumptions. The experiments of 7 projectiles and concrete targets of 2 strength grades were performed. The proposed formula is validated by our experimental data and the classic empirical models. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses upon three themes: all related to aqueous cerium chloride solutions. First, the features in the absorption spectra of CeCl3 solutions do not shift noticeably with concentration and are at similar energies to bands in the solid-state absorption spectrum of , with the exception of the weak band at 297nm which is due to . The broad emission band in solution is only due to ⁎ and the emission quenches at concentrations >0.06M. Bands in the excitation spectra of aqueous CeCl3 solutions apparently change position with increasing concentration, due to absorption by which does not contribute to emission. At concentrations above 1M, there is total extinction of incident radiation for wavelengths shorter than 310nm. Second, this system is chosen to illustrate the revised calculation of centroid shift, by taking into account the vibronic nature of spectral features, in contrast with the pure electronic transition of the free ion. Similar calculations are applicable to other Ce3+ systems. Thirdly, excitation spectra are employed to demonstrate the energy transfer occurring from Ce3+ to Tb3+ and Eu3+ in aqueous chloride solutions, which is an unusual energy transfer, occurring from 5d to 4f states and between hydrated lanthanide ions in solution. [Copyright &y& Elsevier]

• Flow boiling experiments in a rectangular channel under low flow rate are performed. • Orientation effect on HTC for flow boiling is studied. • An HTC transition region is observed within orientation of 45°~60°. • A new HTC correlation is developed by coupling Liu & Winterton correlation and error function. • The new HTC correlation has a good prediction with an error of ±15% comparing with the experimental data. Natural convection boiling in channel with Arc-Shaped will be encountered in the IVR-ERVC (In-Vessel Retention measure by External Reactor Vessel Cooling) system in nuclear power plant under severe accident. The flow and heat transfer characters in this situation is simulated by flow boiling of deionized water in an inclined rectangular channel under low flow rates. This paper aims to separate various parameters (such as orientation, mass flow rate and inlet quality, etc.) to investigate their individual effects on heat transfer coefficient (HTC) in a rectangular channel with cross section of 17 mm × 10 mm. By using a preheater at the inlet of the rectangular channel, the inlet quality could be controlled and the two-phase flow situation could be observed before the fluids entering into the main heater region on one side of the channel wall in downstream. Thus the characteristics of HTC on the main heater could be investigated at different flow patterns. The channel orientations vary from 15 to 90°, the mass flow rates vary from 110 to 288 kg/(m2s) and the qualities vary from 0.003 to 0.036, respectively. Experimental results show that the mass flow rate and quality effects on the HTC are very weak in this study. However, the orientation angle effect on HTC shows an transition region within 45°~60°, while it slowly changes when the orientation angle is smaller than 45° and bigger than 60°. Such tendency could be well formulated by the error function. Compared with different empirical formulas of saturated boiling HTC, it is found that the Liu & Winterton correlation can well predict the experimental HTC results in 90° orientation channel. Based on such correlation and coupled with the error function, a new model was developed by considering the orientation effect, which has an error of ±15% comparing with the experimental data. [ABSTRACT FROM AUTHOR]