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Background: In lung transplantation surgery, extracorporeal life support (ECLS) is essential for safety. Various support methods, including cardiopulmonary bypass (CPB) and off-pump techniques, are used, with extracorporeal membrane oxygenation (ECMO) gaining prominence. However, consensus on the best support strategy is lacking.Purpose: This article reviews risks, benefits, and outcomes of different support strategies in lung transplantation. By consolidating knowledge, it aims to clarify selecting the most appropriate ECLS modality.Research Design: A comprehensive literature review examined CPB, off-pump techniques, and ECMO outcomes in lung transplantation, including surgical results and complications.Study Sample: Studies, including clinical trials and observational research, focused on ECLS in lung transplantation, both retrospective and prospective, providing a broad evidence base.Data Collection and/or Analysis: Selected studies were analyzed for surgical outcomes, complications, and survival rates associated with CPB, off-pump techniques, and ECMO to assess safety and effectiveness.Results: Off-pump techniques are preferred, with ECMO increasingly vital as a bridge to transplant, overshadowing CPB. However, ECMO entails hidden risks and higher costs. While safer than CPB, optimizing ECMO postoperative use and monitoring is crucial for success.Conclusions: Off-pump techniques are standard, but ECMO's role is expanding. Despite advantages, careful ECMO management is crucial due to hidden risks and costs. Future research should focus on refining ECMO use and monitoring to improve outcomes, emphasizing individualized approaches for LT recipients.
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Malignant peritoneal mesothelioma is an exceedingly rare malignant tumor. Herein, we present a case of malignant peritoneal mesothelioma in a 59-year-old Chinese female patient who was stable after treatment for multiple relapses. Imaging revealed massive ascites and an irregular thickening of the peritoneal mesangium. Laparoscopic biopsy revealed heterogeneous cell nests in the parietal peritoneal fibrous tissue, which were confirmed by immunohistochemical staining for Calretinin, WT-1, and D2-40. In terms of genetic screening, BAP1, CSF1R, and other key driver gene variants closely related to malignant peritoneal mesothelioma have been explored in tumor tissues. Notably, CARD11 driver mutation was first found in all malignant peritoneal mesothelioma patients, and ATM A1159T gene mutation found in recurrent focal tissue may be associated with recurrent tumor recurrence.
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The photocatalytic CO2 reduction strategy driven by visible light is a practical way to solve the energy crisis. However, limited by the fast recombination of photogenerated electrons and holes in photocatalysts, photocatalytic efficiency is still low. Herein, a WO3/BiOBr S-scheme heterojunction was formed by combining WO3 with BiOBr, which facilitated the transfer and separation of photoinduced electrons and holes and enhanced the photocatalytic CO2 reaction. The optimized WO3/BiOBr heterostructures exhibited best activity for photocatalytic CO2 reduction without any sacrificial reagents, and the CO yield reached 17.14 µmol g-1 after reaction for 4 h, which was 1.56 times greater than that of BiOBr. The photocatalytic stability of WO3/BiOBr was also improved.
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The slow water-absorption speed of starch-based superabsorbent resin (St-SAP) limits its application. In this study, porous St-SAP (P-St-SAP) was prepared by inverse suspension polymerization and supercritical CO2 drying, the aim is to provide a preparation method of fast absorbent resin. The P-St-SAP at 33 % starch content had an interpenetrating porous structure with macropores, mesopores and micropores, and the surface area, pore volume and average pore diameter were 32.06 m2·g-1, 0.116 cm3·g-1 and 21.6 nm, respectively. The water-absorption process included rapid-section, medium-section and slow-section, according with internal diffusion, double-constant and quasi second-order kinetic models, respectively. In the initial 30 s, a water-absorption speed of 262.6 g·g-1·min-1 in distilled water was much higher than some previous research results, and the equilibrium absorption value of 517.9 g·g-1 in distilled water and 72.9 g·g-1 in 0.9 % saline was better than that of non-porous St-SAP at similar starch content. Moreover, at the same stage the percentage of saline absorption ratio to equilibrium absorption value was 1.0- 2.0 times higher than that of distilled water. These research results indicate that the P-St-SAP has fast water-absorption speed and good salt resistance, which will have greater application prospects in sanitary materials, building concrete pouring, and flood control blocking piping.
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Dióxido de Carbono , Água , Água/química , Amido/química , Porosidade , PolimerizaçãoRESUMO
The Vth stability and gate reliability of AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) with alternating O2 plasma treatment were systematically investigated in this article. It was found that the conduction band offset at the Al2O3/AlGaN interface was elevated to 2.4 eV, which contributed to the suppressed gate leakage current. The time-dependent dielectric breakdown (TDDB) test results showed that the ALD-Al2O3 with the alternating O2 plasma treatment had better quality and reliability. The AlGaN/GaN MIS-HEMT with the alternating O2 plasma treatment demonstrated remarkable advantages in higher Vth stability under high-temperature and long-term gate bias stress.
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The magnetic polymer microsphere is a promising adsorbent due to its high adsorption efficiency and good regeneration ability from wastewater. Cassava starch magnetic porous microspheres (AAM-MSMPMs) were synthesized by graft copolymerization in inverse emulsion. Mechanically activated cassava starch (MS) was used to graft skeletons, vinyl monomers [acrylic acid (AA) and acrylamide (AM)] as copolymerized unsaturated monomers, methyl methacrylate (MMA) as the dispersing agent, and polyethylene glycol/methanol (PEG2000/MeOH) as the porogen. It was found that the AAM-MSMPM adsorbent is superparamagnetic, the saturation magnetization is 14.9 emu·g-1, and it can be rapidly and directionally separated from Cd(II) ions in aqueous solution. The FTIR indicated that the carboxyl and hydroxyl groups were grafted into MS. The AAM-MSMPM had good speroidization and a uniform size. After the porogen was added, the particle size of the AAM-MSMPM decreased from 19.00 to 7.00 nm, and the specific surface area increased from 7.00 to 35.00 m2·g-1. The pore volume increased from 0.03 to 0.13 cm3·g-1. The AAM-MSMPM exhibited a large specific surface area and provided more adsorption active sites for Cd(II) ions. The maximum adsorption capacity of the AAM-MSMPM for Cd(II) ions was 210.68 mg·g-1, i.e., 81.02% higher than that without porogen. Additionally, the Cd(II) ion adsorption process on the AAM-MSMPM can be described by Langmuir isothermal and pseudo-second-order kinetic models. A chemical reaction dominated the Cd(II) ion adsorption process on the AAM-MSMPM, and chemisorption was the rate-controlling step during the Cd(II) ion adsorption process. The AAM-MSMPM still had excellent stability after five consecutive reuses.
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This paper proposed a fully integrated adaptive on-time (AOT) controlled buck converter with fast load transient. An adaptive on-time generator is presented to stabilize the output frequency. To enhance the light load efficiency, the converter could transfer from the pulse width modulation (PWM) to pulse skip modulation (PSM) as the load current decreases. The buck converter can switch between these two modulation modes adaptively with the assistance of a zero current detection circuit. Implemented in the TSMC 0.18 µm BCD (BiCMOS/DMOS) process, the proposed buck converter works with an input voltage ranging from 5.5 to 15 V, an output voltage ranging from 0.5 to 5 V, and an output load ranging up to 5 A. The experimental results show that based on the dual modulation adaptive on-time controlled mode, the transient recovery time from light to heavy load and from heavy load to light load is 13 µs and 15 µs, respectively. An overshot voltage of 57 mV and an undershot voltage of 53 mV are also achieved.
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To improve the water absorbency and water-retention rate of superabsorbent materials, a porous calcium carbonate composite superabsorbent polymer (PCC/PAA) was prepared by copolymerization of acrylic acid and porous calcium carbonate prepared from ground calcium carbonate. The results showed that the binding energies of C-O and C=O in the O 1s profile of PCC/PAA had 0.2 eV and 0.1-0.7 eV redshifts, respectively, and the bonding of -COO- groups on the surface of the porous calcium carbonate led to an increase in the binding energy of O 1s. Furthermore, the porous calcium carbonate chelates with the -COO- group in acrylic acid through the surface Ca2+ site to form multidirectional crosslinking points, which would increase the flexibility of the crosslinking network and promote the formation of pores inside the PCC/PAA to improve the water storage space. The water absorbency of PCC/PAA with 2 wt% porous calcium carbonate in deionized water and 0.9 wt% NaCl water solution increased from 540 g/g and 60 g/g to 935 g/g and 80 g/g, respectively. In addition, since the chemical crosslinker N,N'-methylene bisacrylamide is used in the polymerization process of PCC/PAA, N,N'-methylene bisacrylamide and porous calcium carbonate enhance the stability of the PCC/PAA crosslinking network by double-crosslinking with a polyacrylic acid chain, resulting in the crosslinking network of PCC/PAA not being destroyed after water absorption saturation. Therefore, PCC/PAA with 2 wt% porous calcium carbonate improved the water-retention rate by 244% after 5 h at 60 °C, and the compressive strength was approximately five-times that of the superabsorbent without porous calcium carbonate.
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Temperature-sensitive carboxylated cellulose nanocrystals/N-isopropyl acrylamide aerogels (CCNC-NIPAMs) were developed as novel pesticide-controlled release formulas. Ammonium persulfate (APS) one-step oxidation was used to prepare bagasse-based CCNCs, and then the monomer N-isopropyl acrylamide (NIPAM) was successfully introduced and constructed into the temperature-sensitive CCNC-NIPAMs through polymerization. The results of the zeta potential measurement and Fourier infrared transform spectrum (FTIR) show that the average particle size of the CCNCs was 120.9 nm, the average surface potential of the CCNCs was -34.8 mV, and the crystallinity was 62.8%. The primary hydroxyl group on the surface of the CCNCs was replaced by the carboxyl group during oxidation. The morphology and structure of CCNC-NIPAMs were characterized via electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), compression performance, porosity analysis, and thermogravimetric (TG) analysis. The results demonstrate that CCNC-NIPAM has a high porosity and low density, as well as good thermal stability, which is conducive to loading and releasing pesticides. In the swelling, drug loading, and controlled release process, the CCNC-NIPAM exhibited significant temperature sensitivity. Under the same NIPAM reaction amount, the equilibrium swelling rate of the CCNC-NIPAM first increased and then decreased with increasing temperature, and the cumulative drug release ratio of the CCNC-NIPAM at 39 °C was significantly higher than that at 25 °C. The loading efficiency of the CCNC-NIPAM on the model drug thiamethoxam (TXM) was up to 23 wt%, and the first-order model and Korsmyer-Peppas model could be well-fitted in the drug release curves. The study provides a new method for the effective utilization of biomass and pesticides.
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In this work, we demonstrated a low current collapse normally on Al2O3/AlGaN/GaN MIS-HEMT with in situ H-radical surface treatment on AlGaN. The in situ atomic pretreatment was performed in a specially designed chamber prior to the thermal ALD-Al2O3 deposition, which improved the Al2O3/AlGaN interface with Dit of ~2 × 1012 cm-2 eV-1, and thus effectively reduced the current collapse and the dynamic Ron degradation. The devices showed good electrical performance with low Vth hysteresis and peak trans-conductance of 107 mS/mm. Additionally, when the devices operated under 25 °C pulse-mode stress measurement with VDS,Q = 40 V (period of 1 ms, pulse width of 1 µs), the dynamic Ron increase of ~14.1% was achieved.
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A systematic study of epi-AlGaN/GaN on a SiC substrate was conducted through a comprehensive analysis of material properties and device performance. In this novel epitaxial design, an AlGaN/GaN channel layer was grown directly on the AlN nucleation layer, without the conventional doped thick buffer layer. Compared to the conventional epi-structures on the SiC and Si substrates, the non-buffer epi-AlGaN/GaN structure had a better crystalline quality and surface morphology, with reliable control of growth stress. Hall measurements showed that the novel structure exhibited comparable transport properties to the conventional epi-structure on the SiC substrate, regardless of the buffer layer. Furthermore, almost unchanged carrier distribution from room temperature to 150 °C indicated excellent two-dimensional electron gas (2DEG) confinement due to the pulling effect of the conduction band from the nucleation layer as a back-barrier. High-performance depletion-mode MIS-HEMTs were demonstrated with on-resistance of 5.84 Ω·mm and an output current of 1002 mA/mm. The dynamic characteristics showed a much smaller decrease in the saturation current (only ~7%), with a quiescent drain bias of 40 V, which was strong evidence of less electron trapping owing to the high-quality non-buffer AlGaN/GaN epitaxial growth.
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A novel atomic-level post-etch-surface-reinforcement (PESR) process is developed to recover the p-GaN etching induced damage region for high performance p-GaN gate HEMTs fabrication. This process is composed of a self-limited surface modification step with O2 plasma, following by an oxide removal step with BCl3 plasma. With PESR process, the AlGaN surface morphology after p-GaN etching was comparable to the as-epitaxial level by AFM characterization, and the AlGaN lattice crystallization was also recovered which was measured in a confocal Raman system. The electrical measurement further confirmed the significant improvement of AlGaN surface quality, with one-order of magnitude lower surface leakage in a metal-semiconductor (MS) Schottky-diode and 6 times lower interface density of states (Dit) in a MIS C-V characterization. The XPS analysis of Al2O3/AlGaN showed that the p-GaN etching induced F-byproduct and Ga-oxide was well removed and suppressed by PESR process. Finally, the developed PESR process was successfully integrated in p-GaN gate HEMTs fabrication, and the device performance was significantly enhanced with ~20% lower of on-resistance and ~25% less of current collapse at Vds,Q bias of 40 V, showing great potential of leverage p-GaN gate HEMTs reliability.
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Based on the characteristics of charge reversal around the isoelectric point (pI) of amphoteric starch-containing anionic and cationic groups, amphoteric cassava starch nanoparticles (CA-CANPs) are prepared by a W/O microemulsion crosslinking method using (3-chloro-2-hydroxypropyl) trimethyl ammonium chloride as a cationic reagent and POCl3 as an anionic reagent, and the effects of preparation conditions on the particle size of the CA-CANPs are studied in detail in the present study. CA-CANPs with a smooth surface and an average diameter of 252 nm are successfully prepared at the following optimised conditions: a crosslinking agent amount of 15 wt%, an aqueous starch concentration of 6.0 wt%, an oil-water ratio of 10:1, a total surfactant amount of 0.20 g·mL-1, and a CHPTAC amount of 4.05 wt%. The pH-responsive value of the CA-CANPs can be regulated by adjusting the nitrogen-phosphorus molar ratio in the CA-CANPs. By using CA-CANPs with a pI of 6.89 as drug carriers and the paclitaxel (PTX) as a model drug, the maximum loading rate of 36.14 mg·g-1 is achieved, and the loading process is consistent with the Langmuir isotherm adsorption, with the calculated thermodynamic parameters of ΔH° = -37.91 kJ·mol-1, ΔS° = -10.96 J·mol-1·K-1 and ΔG° < 0. By testing the release rate in vitro, it is noted that the release rates of PTX in a neutral environment (37.6% after 96 h) and a slightly acidic environment (58.65% after 96 h) are quite different, suggesting that the CA-CANPs have the possibility of being a targeted controlled-release carrier with pH responsiveness for antitumor drugs.
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To improve the salt resistance of superabsorbent materials and the gel strength of superabsorbent materials after water absorption, a bagasse cellulose-based network structure composite superabsorbent (CAAMC) was prepared via graft copolymerization of acrylamide/acrylic acid (AM/AA) onto bagasse cellulose using silane coupling agent modified nano-CaCO3 (MNC) and N,N'-methylene bisacrylamide (MBA) as a double crosslinker. The acrylamide/acrylic acid was chemically crosslinked with modified nano-CaCO3 by C-N, and a stable double crosslinked (DC) network CAAMC was formed under the joint crosslinking of N,N'-methylene bisacrylamide and modified nano-CaCO3. Modified nano-CaCO3 plays a dual role of crosslinking agent and the filler, and the gel strength of composite superabsorbent is two times higher than that of N,N'-methylene bisacrylamide single crosslinking. The maximum absorbency of CAAMC reached 712 g/g for deionized water and 72 g/g for 0.9 wt% NaCl solution. The adsorption process of CAAMC was simulated by materials studio, and the maximum adsorption energy of amino and carboxyl groups for water molecules is -2.413 kJ/mol and -2.240 kJ/mol, respectively. According to the results of CAAMC soil water retention, a small amount of CAAMC can greatly improve the soil water retention effect.
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Astragaloside IV (AS-IV), the major active constituent purified from Astragalus membranaceus, was previously reported to have protective effects against cardiac dysfunction. However, the underlying mechanism remains unknown. In the present study, we investigated the protective effect of AS-IV on lipopolysaccharide (LPS)-induced cardiac dysfunction and explored the potential mechanism by focusing on miRNA-1 (miR-1) at the animal and cellular levels. A series of methods were used, including echocardiography, flow cytometry, ELISA, immunofluorescence, transmission electron microscopy, RT-PCR, and western blotting. The results showed that both AS-IV and the miR-1 inhibitor improved cardiac dysfunction, reduced heart injury, inhibited apoptosis and autophagy, and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in the heart tissue of rats treated with LPS. Importantly, AS-IV downregulated the expression of miR-1 mRNA in heart tissue. All effects of AS-IV were at least partly abolished by miR-1 mimics. In the in vitro study, both AS-IV and the miR-1 inhibitor inhibited apoptosis and autophagy and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in heart cells treated with LPS. Similarly, AS-IV downregulated the expression of miR-1 mRNA in heart cells. All effects of AS-IV on cells were at least partly abolished by miR-1 mimics. Furthermore, miR-1 mimics exhibited effects similar to LPS both in animal and cellular studies. Taken together, these results suggest that AS-IV protects against LPS-induced cardiac dysfunction by inhibiting calcium-mediated apoptosis and autophagy by targeting miR-1, highlighting a new mechanism for the therapeutic effect of AS-IV on cardiac dysfunction.