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ObjectiveVeno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a critical support technique for cardiac surgery patients. This study compares the outcomes of femoral artery cannulation vs. combined femoral and axillary artery cannulation in post-cardiotomy VA-ECMO patients. This study aimed to compare the clinical outcomes of critically ill patients post-cardiac surgery under VA-ECMO support using different cannulation strategies. Specifically, the focus was on the impact of femoral artery (FA) cannulation vs. combined femoral artery and axillary artery (FA+AA) cannulation on patient outcomes.MethodsThrough a retrospective analysis, we compared 51 adult patients who underwent cardiac surgery and received VA-ECMO support based on the cannulation strategy employed—FA cannulation in 27 cases vs. FA+AA cannulation in 24 cases.ResultsThe FA+AA group showed significant advantages over the FA group in terms of the incidence of chronic renal failure (CRF) (37.50% vs. 14.81%, p = 0.045), preoperative blood filtration requirement (37.50% vs. 11.11%, p = 0.016), decreased platelet count (82.67 ± 44.95 vs. 147.33 ± 108.79, p = 0.014), and elevated creatinine (Cr) levels (151.80 ± 60.73 vs. 110.26 ± 57.99, p = 0.041), although the two groups had similar 30-day mortality rates (FA group 40.74%, FA+AA group 33.33%). These findings underscore that a combined approach may offer more effective hemodynamic support and better clinical outcomes when selecting an ECMO cannulation strategy.ConclusionDespite the FA+AA group patients presenting with more preoperative risk factors, this group has exhibited lower rates of complications and faster recovery during ECMO treatment. While there has been no significant difference in 30-day mortality rates between the two cannulation strategies, the FA+AA approach may be more effective in reducing complications and improving limb ischemia. These findings highlight the importance of individualized treatment strategies and meticulous monitoring in managing post-cardiac surgery ECMO patients.

Layered double hydroxides (LDH-D) and their calcined counterparts, using dolomite as a source of magnesium, were utilized for the immobilization of chromium (Cr(VI)) in soil. The results indicate that LDH-D, both with and without varying calcination temperatures, can effectively immobilize Cr(VI) in soil. Among the different calcination temperatures tested, LDH-D subjected to calcination at 500 °C (LDH-D-500) showed particularly high efficacy. Long-term TCLP experiments demonstrated the inhibition of soil-to-plant transmission of Cr(VI), thereby highlighting the long-lasting immobilization capacity of LDH-D and its calcined derivatives. Furthermore, the analysis of the microbial community's adaptation in post-remediation soil confirmed the durability and bioavailability of LDH-D-500 for Cr immobilization. Examination of the material's morphology and structure after immobilization shed light on the mechanism of immobilization in soil. The results revealed that interlayer anion exchange and surface adsorption were the main factors responsible for the effective immobilization of LDH-D and LDH-D-300. On the other hand, LDH-D-900, with a dominant spinel (MgAl2O4) structure, faced challenges in returning to its original layered configuration, making surface adsorption the primary mechanism for immobilization. LDH-D-500 primarily relied on the structure memory effects of LDHs to immobilize Cr(VI) through structural recovery processes, facilitated by electrostatic attraction and surface adsorption. It is also important to note that CaCO3 plays an important role in adsorption. Additionally, a portion of Cr(VI) was converted to Cr(III) through phenomena such as isomer substitution and complexation adsorption. The proficiency of LDH-D-500 in immobilizing Cr, its ability for instantaneous separation, and the potential for regeneration make it a promising material for remediation of heavy metal-contaminated soil. The investigations suggest that the use of dolomite to create hydrotalcite and calcining it at 500 °C could effectively render environmental Cr inactive, thereby optimizing resource utilization.

Abstract Lithium- and manganese-rich layered oxide cathode materials have attracted extensive interest because of their high energy density. However, the rapid capacity fading and serve voltage decay over cycling make the waste management and recycling of key components indispensable. Herein, we report a facile concentrated solar radiation strategy for the direct recycling of Lithium- and manganese-rich cathodes, which enables the recovery of capacity and effectively improves its electrochemical stability. The phase change from layered to spinel on the particle surface and metastable state structure of cycled material provides the precondition for photocatalytic reaction and thermal reconstruction during concentrated solar radiation processing. The inducement of partial inverse spinel phase is identified after concentrated solar radiation treatment, which strongly enhances the redox activity of transition metal cations and oxygen anion, and reversibility of lattice structure. This study sheds new light on the reparation of spent cathode materials and designing high-performance compositions to mitigate structural degradation.

The Medium Voltage Direct Current (MVDC) Integrated Power System (IPS) represents the developing trend of marine ship power. It facilitates the provision of high quality energy for weaponry, however, high power load switching will have a severe impact on power system as well as on gas turbine gensets, which is a critical problem needs to be solved urgently. In this paper, based on the traditional IPS hierarchical control strategy, an improved design method of transient power sharing is proposed for multi-gensets operation. Firstly, by analyzing the transient fluctuation process of voltage and speed, the law of system energy coupling transfer is illustrated and a strategy of equalizing torque impact is proposed. Then, a set of speed compensation factors is introduced to achieve the equalization of transient speed regulation (TSR). Finally, the effectiveness of the proposed improved control strategy is verified by MATLAB/Simulink simulation. Compared to before the improvement, the gensets operate away from the limiting boundary of bearing torque impact and speed deviation, and the bus voltage stability is also enhanced.

In the field of high-frequency communications devices, there is an urgent need to develop high-performance copper clad laminates (CCLs) with low dielectric loss (Df) plus good flame retardancy and thermal stability. The hydrocarbon resin styrene-butadiene block copolymer (PSB) was modified with the flame-retardant 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide/polyhedral oligomeric silsesquioxanes (DOPO-POSS) to meet the demands of high-frequency and high-speed applications. The resulting DOPO-POSS-modified PSB was used as the resin matrix along with other additives to fabricate PSB/DOPO-POSS laminates. At a high-frequency of 10 GHz, the laminates containing 20 wt.% of DOPO-POSS and with a thickness of 0.09 mm exhibited a Df of 0.00328, which is much lower compared with the commercial PSB/PX-200 composite (Df: 0.00498) and the PSB without flame retardancy (Df: 0.00453). Afterwards, glass fiber cloth (GF) was used as a reinforcing material to manufacture GF-PSB/DOPO-POSS composite laminates with a thickness of 0.25 mm. The flame retardancy of GF-PSB/DOPO-POSS composite laminate reached vertical burning (UL-94) V-1 grade, and GF-PSB/DOPO-POSS exhibited higher thermal and dynamic mechanical properties than GF-PSB/PX-200. The results of a limited oxygen index (LOI) and self-extinguishing time tests also demonstrated the superior flame-retardant performance of DOPO-POSS compared with PX-200. The investigation indicates that GF-PSB/DOPO-POSS composite laminates have significant potential for use in fabricating a printed circuit board (PCB) for high-frequency and high-speed applications.

The problem of minimizing makespan (maximum completion time) on uniform machines with restricted assignment is considered. The machines differ in their speeds and functionalities. Each job has a set of machines to which it can be assigned, called its processing set. The goal is to finish the jobs as soon as possible. There exist 4/3-approximation algorithms for the cases of inclusive and tree-hierarchical assignment restrictions, under an assumption that machines with higher capabilities also run at higher speeds. We eliminate the assumption and present algorithms with approximation ratios 2 and 4/3 for both cases.

This paper studies the Pareto scheduling problem of minimizing total weighted completion time and maximum cost on a single machine. It is known that the problem is strongly NP-hard. Algorithms with running time $ O(n^3) $ are presented for the following cases: arbitrary processing times, equal release dates and equal weights; equal processing times, arbitrary release dates and equal weights; equal processing times, equal release dates and arbitrary weights.

The performance of energy transportation via implementation of nanoparticles is a hot research area in the modern technological and industrial development era. The boundary-driven Maxwell nanofluid flow over magnetized stretched sheet. The process of bio-convection is accounted under mass and energy transportation. The thermal conductance and activated energy aspects are taken into account. The model is organized by implementing the boundary-layer assumptions. Then, the non-dimensional constraints are utilized to re-construct the mathematical problem. The well-known shooting scheme is incorporated to express the results of problems. The graphical illustrations are reported for the behavior analysis of distinct parameters on quantities of physical and practical importance. The microorganism is augmented due to enlargement in Deborah and magnetic numbers values. An augmentation in temperature is achieved against the incremented thermophoresis and bio-convection constraints.

Abstract Inherent weak photon‐capturing ability is a long‐standing bottleneck for pristine phase change materials (PCMs) in photothermal conversion application. To conquer this difficulty, herein, magnetic Fe3O4 nanoparticles were in situ anchored between the layers and the surface of two‐dimensional MXene for the infiltration of myristic acid (MA) by an in situ chemical anchoring strategy. Benefiting from the synergistic localized surface plasmon resonance effect of MXene and Fe3O4 nanoparticles, our designed MXene@Fe3O4‐MA composite PCMs harvested an ultrahigh photothermal conversion efficiency of 97.7%. During the photothermal conversion process, MXene can capture photons and convert solar energy into heat energy efficiently, and the in situ anchored Fe3O4 nanoparticles further enhanced the photothermal conversion efficiency. Moreover, the introduction of Fe3O4 nanoparticles improved the thermal energy storage density (144.17 J/g) of MXene‐MA composite PCMs since Fe3O4 nanoparticles provided more heterogeneous nucleation sites for MA. Simultaneously, MXene@Fe3O4‐MA composite PCMs were endowed with excellent paramagnetism, and realized efficient magnetic‐thermal conversion. Additionally, MXene@Fe3O4‐MA composite PCMs exhibited excellent energy conversion stability, thermal stability, and reliability after undergoing multiple thermal cycles. Therefore, high‐performance MXene@Fe3O4‐based energy conversion composite PCMs are promising candidates to accelerate efficient utilization of the practical solar energy and magnetic energy

Abstract Background The prognostic value of serum bilirubin in stroke is controversial, since bilirubin has both neuroprotective and neurotoxic properties. We aimed to investigate the association between serum bilirubin, including total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) and poor functional outcomes in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA). Methods All patients with AIS or TIA were recruited from the Third China National Stroke Registry. The poor functional outcomes included modified Rankin Scale (mRS) score 2–6 and 3–6 at 3 months and 1 year. Multivariable logistic regression was used to investigate the associations of TBIL, DBIL, and IBIL with poor functional outcomes. Results Among 11,121 enrolled patients, the median (interquartile range) of TBIL, DBIL, and IBIL was 13.30 (9.90–17.70), 3.80 (2.70–5.30), and 9.30 (6.70–12.80) µmol/L. After adjustment for conventional confounding factors, patients in the highest TBIL quartile had the highest proportion of mRS score 2–6 at 3 months (odds ratio [OR], 1.37; 95 % confidence interval [CI], 1.19–1.59) and 1 year (OR, 1.31; 95 % CI, 1.13–1.52), and mRS score 3–6 at 3 months (OR, 1.33; 95 % CI, 1.11–1.59) and 1 year (OR, 1.28; 95 % CI, 1.07–1.53), when compared to patients in the lowest TBIL quartile. Similar results were observed for DBIL and IBIL. We also found J-shaped associations between serum bilirubin levels and each outcome. Conclusions Elevated levels of serum bilirubin were significantly associated with poor functional outcomes in patients with AIS or TIA at 3 months and 1 year.

The immobilization of homogeneous catalysts has always been a hot issue in the field of catalysis. In this paper, in an attempt to immobilize the homogeneous [Ni(Me6Tren)X]X (X = I, Br, Cl)-type catalyst with porous organic polymer (POP), the heterogeneous catalyst PBTP-Me6Tren(Ni) (POP-Ni) was designed and constructed by quaternization of the porous bromomethyl benzene polymer (PBTP) with tri[2-(dimethylamino)ethyl]amine (Me6Tren) followed by coordination of the Ni(II) Lewis acidic center. Evaluation of the performance of the POP-Ni catalyst found it was able to catalyze the CO2 cycloaddition with epichlorohydrin in N,N-dimethylformamide (DMF), affording 97.5% yield with 99% selectivity of chloropropylene carbonate under ambient conditions (80 °C, CO2 balloon). The excellent catalytic performance of POP-Ni could be attributed to its porous properties, the intramolecular synergy between Lewis acid Ni(II) and nucleophilic Br anion, and the efficient adsorption of CO2 by the multiamines Me6Tren. In addition, POP-Ni can be conveniently recovered through simple centrifugation, and up to 91.8% yield can be obtained on the sixth run. This research provided a facile approach to multifunctional POP-supported Ni(II) catalysts and may find promising application for sustainable and green synthesis of cyclic carbonates.

Due to the advantages of high convergence accuracy, fast training speed, and good generalization performance, the extreme learning machine is widely used in model identification. However, a gas turbine is a complex nonlinear system, and its sampling data are often time-sensitive and have measurement noise. This article proposes an online sequential regularization extreme learning machine algorithm based on the forgetting factor (FOS_RELM) to improve gas turbine identification performance. The proposed FOS_RELM not only retains the advantages of the extreme learning machine algorithm but also enhances the learning effect by rapidly discarding obsolete data during the learning process and improves the anti-interference performance by using the regularization principle. A detailed performance comparison of the FOS_RELM with the extreme learning machine algorithm and regularized extreme learning machine algorithm is carried out in the model identification of a gas turbine. The results show that the FOS_RELM has higher accuracy and better robustness than the extreme learning machine algorithm and regularized extreme learning machine algorithm. All in all, the proposed algorithm provides a candidate technique for modeling actual gas turbine units.

The Li-S battery is a promising next-generation technology due to its high theoretical energy density (2600 Wh kg−1) and low active material cost. However, poor cycling stability and coulombic efficiency caused by polysulfide dissolution have proven to be major obstacles for a practical Li-S battery implementation. In this work, we develop a novel strategy to suppress polysulfide dissolution using hydrofluoroethers (HFEs) with bi-functional, amphiphlic surfactant-like design: a polar lithiophilic “head” attached to a fluorinated lithiophobic “tail.” A unique solvation mechanism is proposed for these solvents whereby dissociated lithium ions are readily coordinated with lithiophilic “head” to induce self-assembly into micelle-like complex structures. Complex formation is verified experimentally by changing the additive structure and concentration using small angle X-ray scattering (SAXS). These HFE-based electrolytes are found to prevent polysulfide dissolution and to have excellent chemical compatibility with lithium metal: Li||Cu stripping/plating tests reveal high coulombic efficiency (>99.5%), modest polarization, and smooth surface morphology of the uniformly deposited lithium. Li-S cells are demonstrated with 1395 mAh g−1 initial capacity and 71.9% retention over 100 cycles at >99.5% efficiency—evidence that the micelle structure of the amphiphilic additives in HFEs can prohibit polysulfide dissolution while enabling facile Li+ transport and anode passivation.

Ship maintenance requires the use of a lot of resources, and the schedule risk caused by resource factors is an important reason for the long time and easy delay of maintenance projects. This paper adopts system dynamics theory to analyze the dynamic relationship between activity delay and resource allocation factors, and establishes a risk assessment model. Use anylogic software to simulate the implementation process of activities, and effectively simulate the mutual influence and change process of various risk factors, so as to achieve the purpose of accurately and effectively estimating the duration of project activities.

A facile method was developed to prepare antimony doped tin oxide (Sb-SnO2)/carbon aerogel (CA) for use as an electrocatalytic filtration membrane. The preparation process included synthesis of a precursor sol, impregnation, and thermal decomposition. The Sb-SnO2, which was tetragonal in phase with an average crystallite size of 10.8 nm, was uniformly distributed on the CA surface and firmly attached via carbon-oxygen-tin chemical bonds. Preliminary filtration tests indicated that the Sb-SnO2/CA membrane had a high rate of total organic carbon removal for aqueous tetracycline owing to its high current efficiency and electrode stability.

In this work, an electrocatalytic membrane was prepared to degrade aqueous tetracycline (TC) using a carbon membrane coated with nano-TiO2 via a sol-gel process. SEM, XRD, EDS, and XPS were used to characterize the composition and structure of the electrocatalytic membrane. The effect of operating conditions on the removal rate of tetracycline was investigated systematically. The results show that the chemical oxygen demand (COD) removal rate increased with increasing residence time while it decreased with increasing the initial concentration of tetracycline. Moreover, pH had little effect on the removal of tetracycline, and the electrocatalytic membrane could effectively remove tetracycline with initial concentration of 50 mg·L−1 (pH, 3.8–9.6). The 100% tetracycline and 87.8% COD removal rate could be achieved under the following operating conditions: tetracycline concentration of 50 mg·L−1, current density of 1 mA·cm−2, temperature of 25 °C, and residence time of 4.4 min. This study provides a new and feasible method for removing antibiotics in water with the synergistic effect of electrocatalytic oxidation and membrane separation. It is evident that there will be a broad market for the application of electrocatalytic membrane in the field of antibiotic wastewater treatment.