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1.
Small ; 20(9): e2306233, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37849033

RESUMO

The nitrides and carbides of transition metals are highly favored due to their excellent physical and chemical properties, among which MXene is a hot research topic for microwave absorption. Herein, the controlled preparation of 3D Mo2 TiC2 Tx -based microspheres toward microwave absorption is reported for the first time. With the merits of the performances of both reduced graphite oxide (RGO) and MXene sufficiently considered, the influence of carbonization temperature on the internal crystal structure and the effective microwave-material interaction surface of the prepared Mo2 TiC2 Tx /RGO is systematically investigated. The structure-activity relationships relating the apparent morphology and crystal structure to the microwave absorption performance are deeply explored, and the wave absorption mechanism is put forward as well. The results show that the Mo2 TiC2 Tx /RGO-700 product obtained after heating treatment at 700 °C exhibits excellent microwave absorption performance, with the RLmin being up to -55.1 dB@2.1 mm@13.8 GHz, and the corresponding effective absorption bandwidth covering 5.7 GHz. The outstanding microwave absorption characteristics are attributed to the appropriate impedance matching, high specific surface area, rich intrinsic defects, desirable conductivity, and strong multipolarization capabilities. This work enriches the types of MXene-based composite absorbers and provides a new strategy for controlled preparation of high-performance 3D composite absorbers.

2.
Small ; : e2402000, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752453

RESUMO

This work reports on the preparation of uniform vesicle-structural carbon spheres doped with heteroatoms of N, P, and S, with the pore sizes strictly controlled by the hard templates of monodisperse submicron SiO2 spheres. The uniformly doped vesicular carbon microspheres are obtained in three steps: Stöber hydrolysis for the SiO2; in situ polymerization for the immobilization; and alkaline etching after carbonization. The size of the vesicles can be easily adjusted by regulating the particle size of the submicron SiO2 spheres, which has a significant effect on its electromagnetic wave (EMW) absorption performance. Compared with microspheres with pore sizes of 180 and 480 nm, when the vesicle aperture is 327 nm, with only 5.5 wt.% filling load and 1.9 mm thickness, the material shows the best EMW absorption behavior with the effective absorption bandwidth (EAB) covers the entire Ku band (6.32 GHz) and the minimum reflection loss (RLmin) of -36.10 dB, suggesting the optimized pore size of the microspheres can significantly improve the overall impedance matching of the material and achieve broadband wave absorption. This work paves the way for the enhancement of EMW absorption properties of porous material by optimizing the pore size of uniform apertures while maintaining their composition.

3.
Small ; : e2402632, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012068

RESUMO

Porous carbon nanomaterials are widely applied in the electromagnetic wave absorption (EMWA) field. Among them, an emerging flower-like carbon nanomaterial, termed carbon nanoflowers (CNFs), has attracted tremendous research attention due to their unique hierarchical flower-like structure. However, the design of flower-like carbon nanomaterials with different magnetic cores for EMWA has rarely been reported. Herein, a general template method is proposed to achieve a set of high-quality magnetic CNFs, namely Co@Void@CNFs, CoNi@CNFs, and Ni@CNFs. The prepared magnetic CNFs have highly accessible surface area and internal space, rich heteroatom content, multi-scale pore system, and uniform and highly dispersed magnetic nanoparticles, as a result, deliver superior EMWA performance. Specifically, when the thickness is 2.6 mm, the Co@Void@CNFs exhibit a maximum refection loss (RLmax) of -56.6 dB and an effective absorption bandwidth (EAB) from 8.0 to 12.1 GHz covering the whole X band. The CoNi@CNFs have an RLmax of up to -57.6 dB and a wide EAB of 5.6 GHz at just 1.9 mm. For the Ni@CNFs, possess an ultra-broad EAB of 6.1 GHz, covering the entire Ku band at 2.0 mm. Overall, the hierarchical magnetic carbon nanoflowers proposed here offer new insights toward realizing multifunctional integrated carbon nanomaterials for EMWA.

4.
World J Surg Oncol ; 22(1): 7, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172888

RESUMO

OBJECTIVE: There is no scientific consensus about the treatment of perforated gastric cancer (PGC). Therefore, the aim of this study was to investigate which is the better treatment option for PGC between the single-stage and two-stage strategies. METHODS: All 81 PGC patients from 13 medical institutions were retrospectively enrolled in this study. The PGC patients who underwent R0 gastrectomy were divided into one-stage surgery and two-stage surgery groups. The clinicopathological characteristics of the two groups were compared, and 415 regular gastric cancer patients without perforation were randomly selected as a control. The propensity score matching (PSM) method was used to find matched regular GC patients with similar clinicopathological parameters. The OS (overall survival) and the number harvested lymph nodes from PGC patients and regular GC patients were compared. RESULTS: Compared with PGC patients who underwent one-stage surgery, those who underwent two-stage surgery harvested significantly more lymph nodes [31(27, 38) vs 17 (12, 24), P < 0.001], required less blood transfusion [0 (0, 100) vs 200 (0, 800), P = 0.034], had a shorter ICU stay [0 (0, 1.5) vs 3 (0, 3), P = 0.009], and had a significantly better OS (Median OS: 45 months vs 11 months, P = 0.007). Compared with propensity score-matched regular GC patients without perforation, PGC patients who underwent one-stage gastrectomy had a poorer quality of lymphadenectomy [17 (12, 24) vs 29 (21, 37), P < 0.001] and suffered a worse OS (Median OS: 18 months vs 30 months, P = 0.024). Conversely, two-stage gastrectomy can achieve a comparable quality of lymphadenectomy (P = 0.506) and a similar OS (P = 0.096) compared to propensity score-matched regular GC patients. CONCLUSIONS: For PGC patients in poor condition, two-stage treatment is a better option when D2 radical gastrectomy cannot be achieved in emergency surgery, based on our findings that two-stage gastrectomy could provide PGC patients with a better quality of lymphadenectomy and a better OS.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Pontuação de Propensão , Laparoscopia/métodos , Excisão de Linfonodo/métodos , Gastrectomia/métodos , Resultado do Tratamento
5.
Small ; 19(7): e2205925, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36507608

RESUMO

Advanced carbon materials are constantly being used in the field of microwave absorption. Herein, in order to enrich the variety and expand the application fields of graphdiyne (GDY), the wrinkled graphene (RGO) nanosheet coated and embedded with GDY porous microspheres (RGO/GDY) are prepared by GDY synthesis, ultrasonic spray, and pyrolysis. The study finds that RGO and GDY have effective synergistic effects. The suitable pores and composition, conductive network formed by overlapping 0D and 2D materials, special surface and internal morphology design, and high-temperature activation process make RGO/GDY exhibit excellent impedance matching and attenuation capabilities. Under the best amount of GDY (20 mg), the particle sizes of the microspheres (≈6 µm), and filler content (27.5%), the minimum reflection loss (RLmin ) is -58 dB@8.3 GHz, and the corresponding matching thickness is 2.7 mm. The effective absorption bandwidth is 4.3 GHz as the thickness is 1.9 mm. By adjusting the thickness, the absorber can completely absorb microwaves of all the C, X, and Ku bands. The microwave absorbing mechanisms are elucidated. GDY materials are first applied to the field of microwave absorption, enhancing the absorption performance of RGO/GDY. It provides a new way to manufacture electromagnetic wave absorbers with satisfactory performance.

6.
Soft Matter ; 19(40): 7815-7827, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37796103

RESUMO

The bending tendency of a surfactant monolayer at an interface is critical in determining the type of emulsion formed and the proximity of the emulsion system to its equilibrium state. Despite its importance, the influence of interaction and surfactant structure on the bending tendency has not been quantitatively investigated. In this study, we develop and validate an artificial neural network (ANN) model based on the torque densities from dissipative particle dynamics (DPD) simulations to address this gap. With the validated ANN model, the relationship between surfactant monolayer bending tendency and all the interaction parameters, oil size, and surfactant structure (size and tail branching) was derived, from which the significance of each factor was ranked. With this ANN model, both the relationship and factor analysis can be instantly investigated without further DPD modeling. Furthermore, we expand the study to surfactant-oil-polar solvent (SOP) systems by varying the interaction parameters between polar solvents (PP). Our finding indicates that the interaction between polar solvents plays an important role in determining the bending tendency of surfactant monolayers; weaker intermolecular attraction between polar solvents makes surfactants tend to bend toward the oil phase (tend to form oil in polar solvent emulsion). Factor analysis reveals that increasing the repulsion between head-head (HH) or head-oil (HO) makes the model surfactants more polar-solvophilic, while increasing the repulsion between polar solvent-head (PH), tail-tail (TT) or oil-oil (OO) makes the model surfactants more lipophilic. The ANN model effectively reproduces the dependence of surfactant monolayer bending tendency on oil size, consistent with experimental observations, the larger the oil size, the higher the bending tendency toward the oil phase. The most intriguing insight derived from the ANN model here is that the effect of branching in the lipophilic tail will be enhanced by factors that make surfactants behave more lipophilic in a surfactant-oil-polar solvent (SOP) system, for rather polar-solvophilic surfactants, the effect of tail branching is negligible.

7.
Small ; 18(14): e2107370, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35152557

RESUMO

Constructing hierarchical micro/nanostructures as anodes for sodium ion batteries is an important approach for exploiting efficient energy storage devices. Herein, sandwich structure hierarchical nanofibers composed of hollow carbon fibers as the substrate, and MoS2 as the interlayer with Co and/or ZnS nanoparticles anchoring in carbon skeletons as the outer shell (carbon nanofiber/MoS2 /Co-ZnS⊂NC) are prepared via a multistep reaction strategy. Profiting from the unique hierarchical structure, abundant migration channels of Na+ , and multicomponent synergistic effects, the rapid diffusion kinetics are ensured and the utilization of active materials is maximized. The coaxial structure can evenly disperse volumetric strain, making structural stability guaranteed. Hierarchical nanofibers deliver a high reversible capacity of 352.3 mAh g-1 at 5.0 A g-1 over 3000 cycles. A discharge capacity of 182.5 mAh g-1 is retained even after 10 000 cycles at 10.0 A g-1 as well as a high rate capacity of 202.0 mAh g-1 up to 30 A g-1 . The optimal atomic ratio of Co element is further verified by the kinetic analysis. The full-cells assembled with Na3 V2 (PO4 )3 cathode provide a high capacity of 179.2 mAh g-1 at 1.0 A g-1 for 500 cycles. Combining in situ and ex situ characterizations and theoretical calculations, possible sodium storage mechanisms and the origin of superior electrochemical properties are revealed.

8.
Retina ; 42(6): 1095-1102, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35152245

RESUMO

PURPOSE: To solve the problem of automatic grading of macular edema in retinal images in a more stable and reliable way and reduce the workload of ophthalmologists, an automatic detection and grading method of diabetic macular edema based on a deep neural network is proposed. METHODS: The enhanced green channels of fundus images are input into the YOLO network for training and testing. Diabetic macular edema is graded according to the distance of the macula and hard exudate. We used multiscale feature fusion to form more comprehensive features on different grain images to improve the effect of hard exudate detection. We adopted K-means++ algorithm to cluster anchor box size and use loss of the original network to guide the regression of hard exudate bounding box and improve the regression accuracy of anchor boxes. We increased the diversity of samples for sample training by data augmentation, including cropping, flipping, and rotating of fundus images, so that each batch of training data can better represent the distribution of samples. RESULTS: The detection accuracy of the proposed method can reach 96% on the MESSIDOR data set. The detection rates of hard exudate with high, median, and low probability are 100%, 79.12%, and 60.40%, respectively. CONCLUSION: The proposed method exhibits a very good detection stability on healthy and diseased fundus images.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Algoritmos , Retinopatia Diabética/diagnóstico , Fundo de Olho , Humanos , Edema Macular/diagnóstico , Redes Neurais de Computação
9.
Eur Spine J ; 31(7): 1719-1727, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35624356

RESUMO

PURPOSE: Dural ossification (DO) is common in patients with ossification of the ligamentum flavum (OLF) and is the leading cause of dural tears. However, the methods used for DO diagnosis are limited. The purpose of this study was to propose a novel CT-based imaging sign, Banner cloud sign (BCs), and clarify its clinical characteristics and correlations with DO. METHODS: 57 OLF patients who underwent thoracic spine decompression surgery in our single-center between January- and October-2018 were recruited and divided into two groups based on the presence of DO. Patient demographics and radiographic data were analyzed. Hematoxylin-eosin staining and micro-CT were used to detect the micro-morphological changes of DO. The diagnostic value of BCs for DO was assessed by sensitivity and specificity. RESULTS: 12 patients with a total of 19 segments were diagnosed as DO. The incidence of DO was 21.1% (12/57) in OLF patients and 9.5% (19/200) in OLF segments. Patients with DO had a shorter disease duration and a higher incidence of cerebrospinal fluid leakage than those without DO. Hematoxylin-eosin staining and micro-CT showed that the dura mater was ossified and fused with ossified ligamentum flavum, and diffusion along the dura mater, like a banner cloud flying on the mountain. The sensitivity and specificity of BCs in DO diagnosis were 78.9 and 90.6%, respectively. CONCLUSION: BCs can vividly and intuitively describe the imaging features of DO and has high diagnostic accuracy. It could be a promising and valuable method for the diagnosis of DO.


Assuntos
Ligamento Amarelo , Ossificação Heterotópica , Descompressão Cirúrgica/métodos , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Ligamento Amarelo/diagnóstico por imagem , Ligamento Amarelo/cirurgia , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/etiologia , Osteogênese , Estudos Retrospectivos , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Resultado do Tratamento
10.
Nanotechnology ; 31(22): 225605, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32059206

RESUMO

A three-step synthesis strategy has been applied to the preparation of Co9S8-loaded tubular carbon nanofibers (CTCNFs/Co9S8 hybrid nanofibers) with excellent microwave absorbing ability. Firstly, tubular polymer nanofibers (TPNFs) are synthesized using the confined self-condensation method that we developed. Afterwards, TPNFs are converted into surface carboxylated tubular carbon nanofibers (CTCNFs) by carbonization and subsequent acidification processes. Finally, a hydrothermal method is used for the controllable growth of Co9S8 nanoparticles on CTCNFs, and a series of CTCNFs/Co9S8 hybrid nanofibers with different Co9S8 loading are obtained. The prepared CTCNFs/Co9S8 hybrid nanofibers possess abundant effective interface and defect dipoles, which will lead to stronger polarization. Using the strategy of enhancing dielectric loss, the microwave dissipation ability of CTCNFs/Co9S8 hybrid nanofibers has been significantly improved, showing an excellent low-frequency absorbing performance with a minimum reflection loss of -46.81 dB@5.3 GHz. In addition, the composition, structure and properties of nanofibers have been systematically characterized. The Co9S8 loading on CTCNFs and the filler content of CTCNFs/Co9S8 hybrid nanofibers in matrix are studied and optimized. The microwave attenuation mechanism is also explained.

11.
J Sep Sci ; 43(5): 996-1002, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31837090

RESUMO

Bovine serum albumin imprinted magnetic microspheres, with functional monomers of modified chitosan, N-isopropylacrylamide and sulfobetaine methacrylate, were successfully prepared and characterized in detail. Computational analyses showed that during the preparation process, modified chitosan can effortlessly form multiple non-covalent bonds with protein molecules. Temperature-sensitive N-isopropylacrylamide improves the elution efficiency by abating the mass transfer resistance. Meanwhile, the zwitterionic sulfobetaine methacrylate strongly interacts with H2 O molecules, remarkably reducing the non-specific adsorption. The specific bovine serum albumin adsorption performances of the prepared imprinted material were then determined. The adsorption amount reached 86.87 mg/g and the imprinting factor was 6.49. These excellent specific adsorption properties are attributed to the synergetic effects of the different monomers. The fabricated imprinted material not only exhibits great prospects as a biosensor or separation material for protein molecules, but also provides a collaborative strategy for preparing multi-functional imprinted materials.


Assuntos
Microesferas , Impressão Molecular , Soroalbumina Bovina/análise , Temperatura , Adsorção , Animais , Bovinos , Substâncias Macromoleculares/química , Fenômenos Magnéticos , Tamanho da Partícula , Propriedades de Superfície
12.
Macromol Rapid Commun ; 40(17): e1800768, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30861587

RESUMO

In the present work, the suspension polymerization method is used for the preparation of porous polymer microspheres with different surface morphology, and the preparation mechanism is systematically expounded. The morphology results show that the smooth, convex, and wrinkled microspheres could be controlled by adjusting the ratio of monomer to porogens. The micelles forming the framework support the "Eggshell," and its size and shape directly affect the morphology of "Eggshell." The addition of monomers (GMA), whose polymer has low glass transition temperature (Tg ), is important for the formation of wrinkled morphology. The amount of toluene and polydimethylsiloxane also affects the surface morphology of microspheres. In addition, the effect of polydimethylsiloxane is also more significant. The preparation process of the wrinkled P(GMA-St-EGDA) microspheres with abundant epoxy groups can be amplified. The morphology of the material prepared in the 100 L reactor is well maintained, and the yield in the size range of 80-160 µm is more than 80%. The surface wrinkled porous polymer microspheres have potential applications in the fields of enzyme carrier, separation and purification, and light scattering.


Assuntos
Compostos de Epóxi/química , Microesferas , Transição de Fase , Polimerização , Polímeros/química , Porosidade , Propriedades de Superfície , Suspensões
13.
BMC Musculoskelet Disord ; 18(1): 141, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28376780

RESUMO

BACKGROUND: Data about minimally invasive surgery for the treatment of patients with degenerative disc disease (DDD) has been reported. However, no quantitative knowledge about the biomechanical characteristics of the spinous processes in patients with DDD after operation was reported in the literature. METHODS: Fourteen adult patients with DDD at the L3-4 level were recruited and scanned using computed tomography (CT) to construct three-dimensional (3D) anatomical vertebral models of L2-5. These patients were asked to maintain four positions to acquire 6DOF data about the area of the spine being investigated (L2-5). Fluoroscopy was used to capture spinal motion. 6DOF data from the fluoroscopic images of the four positions was compared to evaluate the kinematics before operation and 6 months after direct lateral interbody fixation (DLIF). RESULTS: Altered kinematics were found mainly in rotation. For the images captured while patients were in the supine position, no significant differences were detected in different functional positions before and after operation. At other positions, the most kinematic involved level was the L3-4 level, which was followed by the L4-5 level. The range of flexion-extension motion at all levels decreased after operation (by an average of 1° to 7°) while different trends were found in left-right bending/rotation. Overall, after surgical treatment, functional activities were partially restored. CONCLUSIONS: Overall the lumbar spinous processes (LSP) at each level responded differently, regarding rotation, before and after DLIF. This data provides new insights for the evaluation of function before and after surgical treatment in patients with LSP disease.


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Fusão Vertebral , Fenômenos Biomecânicos , Feminino , Humanos , Imageamento Tridimensional , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Tomografia Computadorizada por Raios X
14.
Macromol Rapid Commun ; 37(1): 47-52, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26479068

RESUMO

Polymer microcavities with adjustable openings and surface roughness are fabricated on a large scale via single-hole poly(glycidyl methacrylate) (PGMA) swelling seed particles. The size of openings of these microcavities can be adjusted by changing the amount of hydrophilic monomer, and the degree of surface roughness is easily regulated relying on the adjustment of the polarity of monomer. Furthermore, the morphology of PGMA/poly(styrene-methacrylic acid) (PGMA/P(S-MAA)) microparticles from microcavity to erythrocyte shape is controlled by the polarity of seed surface. From transmission electron microscopy images of PGMA/P(S-MAA) microparticles, a fresh polymer particle appears in the cavity. To confirm this phenomenon, thermal annealing process in dioxane/water solution is carried out. Considering the flexibility of polymers, the openings and closing of the prepared microparticles are regulated following the increase in volume ratio of dioxane/water. Ball-in-bowl-shaped PGMA/P(S-MAA) microparticles are further presented, which proves secondary nucleation of monomer in the polymerization stage.

15.
J Sep Sci ; 38(19): 3477-86, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26226935

RESUMO

A novel bovine serum albumin (BSA) surface imprinted polymer based on ZnO rods was synthesized by surface grafting copolymerization. It exhibited an excellent recognition performance to bovine serum albumin. The adsorption capacity and imprinting factor of bovine serum albumin could reach 89.27 mg/g and 2.35, respectively. Furthermore, the fluorescence property of ZnO was used for tracing the process of protein imprinting and it implied the excellent optical sensing property of this material. More importantly, the hypothesis that the surface charge of carrier could affect the imprinting process was confirmed. That is, ZnO with positive surface charge could not only improve the recognition specificity of binding sites to template proteins (pI < 7), but also deteriorate the bindings between sites and non-template proteins (pI > 7). It was also important that the reusability of ZnO@BSA molecularly imprinted polymers was satisfactory. This implied that the poor mechanical/chemical stability of traditional zinc oxide sensors could be solved by the introduction of surface grafting copolymerization. These results revealed that the ZnO@BSA molecularly imprinted polymers are a promising optical/electrochemical sensor element.


Assuntos
Técnicas Biossensoriais/métodos , Impressão Molecular/métodos , Soroalbumina Bovina/química , Óxido de Zinco/química , Adsorção , Animais , Materiais Biomiméticos/química , Bovinos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Nanotubos/química , Nanotubos/ultraestrutura , Polimerização , Polímeros/química , Propriedades de Superfície
16.
Heliyon ; 10(11): e32200, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912461

RESUMO

Aiming at the difficult problems of the large deformation in weakly cemented soft rock roadways, the reasons of large deformation are analyzed for roadways in Hongqingliang coal mine. On this basis, the principle of step by step combined support technology based on allowable deformation + limiting shape for weakly cemented soft rock roadway is proposed, and the optimal support parameters of step by step combined technology are determined by FLAC3D. Step by step combined support technology includes the primary support of anchor bolt + anchor cable + initial shotcrete and the secondary support of U-shaped steel shed + filling flexible material behind shed + control of key parts. The comparative analysis on the site shows that the deformation rate and final deformation amount of the surrounding rock after the step by step combined support are less than those of the primary support, and the deformation of the surrounding rock can be controlled effectively after the secondary support is added. Step by step combined support is superior to the traditional bolt + anchor cable combined repair in terms of economy and efficiency. The optimal construction period of each working procedure of the step by step combined technology is 28 days after the completion of the first support, and the step by step combined support based on allowable deformation + limiting shape is an effective way to control the surrounding rock of soft rock roadway.

17.
ACS Nano ; 18(11): 8411-8422, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38436229

RESUMO

Exploring anticorrosion electromagnetic wave (EMW) absorbing materials in harsh conditions remains a challenge. Herein, S-NiSe/HG nanocomposites encapsulated in room-temperature self-healing polyurethane (S-NiSe/HG/SPU) were exploited as superior anticorrosion EMW absorbing materials. A dual-defect engineering collaborative Schottky interface construction endows S-NiSe/HG with a high vacancy concentration, abundant defects, and moderate conductivity. These structural merits synergistically balance dielectric loss by enhancing dipole-interface polarization loss and optimizing conduction loss. As a result, S-NiSe/HG demonstrates the optimal EMW absorption performance with a minimum reflection loss (RLmin) of -54.8 dB and an adequate absorption bandwidth (EAB) of 7.1 GHz. Besides, S-NiSe/HG/SPU combines the maze effect of S-NiSe/HG with the active repair capability of SPU, thereby providing long-term corrosion resistance for the Mg alloy. Even under corrosion for 10 days, S-NiSe/HG/SPU affords a low corrosion current density (1.3 × 10-5 A) and high charge transfer resistance (3796 Ω cm2). Overall, this work provides valuable insights for in-depth exploration of dielectric loss and development of multifunctional EMW-absorbing materials.

18.
Biomedicines ; 12(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38540291

RESUMO

Oxeiptosis is a reactive oxygen species (ROS)-induced pathway of cell death. The involvement of circular RNAs (circRNAs) has been confirmed in the incidence and progression of intervertebral disc degeneration (IVDD). However, whether oxeiptosis occurs in IVDD and how circRNAs regulate oxeiptosis is still unclear. In this study, we discovered that oxeiptosis could be induced in nucleus pulposus cells (NPCs), and circFOXO3 was significantly upregulated after oxeiptosis induction. Transfection using circFOXO3 small interfering RNA (siRNA) significantly inhibited oxeiptosis in NPCs. Mechanistically, circFOXO3 upregulated acid-sensing ion channel subunit 1 (ASIC1) expression by functioning as a molecular sponge for miR-185-3p and miR-939-5p. Subsequent rescue experiments validated that circFOXO3 could regulate oxeiptosis in NPCs via the miR-185-3p/miR-939-5p-ASIC1 axis. Further research on ASIC1 functions indicated that this regulation was achieved by affecting the Calcium ion (Ca2+) influx mediated by ASIC1. A mouse IVDD model was established, and silencing circFOXO3 in vivo was found to inhibit IVDD development and the activation of the oxeiptosis-related pathway. Overall, circFOXO3 is one of the factors contributing to the progression of IVDD by mediating oxeiptosis.

19.
Int J Biol Macromol ; 261(Pt 1): 129688, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280695

RESUMO

The increasing demand for gold because of its high market price and its wide use in the electronic industry has attracted interest in gold recovery from electronic waste (e-waste). Gold is being dumped as solid e-waste which contains gold concentrations ten times higher than gold ores. Adsorption is a widely used approach for extracting gold from e-waste due to its simplicity, low cost, high efficiency, and reusability of adsorbent material. Natural polysaccharides received increased attention due to their natural abundance, multi-functionality, biodegradability, and nontoxicity. In this review, a brief history, and advancements in this technology were evaluated with recent developments in the preparation and mechanism advancements of natural polysaccharides for efficient gold recovery. Moreover, we have discussed some bifunctional modified polysaccharides with detailed gold adsorption mechanisms. The modified adsorbent materials developed from polysaccharides coupled with inorganic/organic functional groups would demonstrate an efficient technology for the development of new bio-based materials for efficient gold recovery from e-waste. Also, future views are recommended for highlighting the direction to achieve fast and effective gold recovery from e-waste in a friendly and sustainable manner.


Assuntos
Resíduo Eletrônico , Ouro , Resíduo Eletrônico/análise , Resíduos Sólidos , Tecnologia , Eletrônica
20.
Artigo em Inglês | MEDLINE | ID: mdl-38918062

RESUMO

AIMS: Ischemic heart disease (IHD) has been a significant public health issue worldwide. This study aims to predict the global burden of IHD in a timely and comprehensive manner. METHODS AND RESULTS: Incidence, prevalence, deaths, and disability-adjusted life years (DALYs) for IHD from 1990 to 2021 were derived from the Global Burden of Disease 2021 database and three models (linear, exponential, and Poisson regression) were used to estimate their trends over time at the global, regional, and national levels by age, sex, and country groups, with the gross domestic product per capita was applied to adjust the model. The model results revealed that the global burden of IHD is expected to increase continuously by 2050. By 2050, global IHD incidence, prevalence, deaths, and DALYs are projected to reach 67.3 million, 510 million, 16 million, and 302 million, respectively, which represents an increase of 116%, 106%, 80%, and 62% from 2021. Moreover, the results showed that regions with lower socio-demographic index (SDI) bore a greater burden of IHD than those with higher SDI, with men having a higher burden of IHD than women. People over 70 years old account for a major part of the burden of IHD, and premature death of IHD is also becoming more serious. CONCLUSION: The global burden of IHD will increase further by 2050, potentially due to population aging and economic disparities. Hence, it is necessary to strengthen the prevention of IHD and formulate targeted strategies according to different SDI regions and special populations.

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