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1.
J Colloid Interface Sci ; 670: 460-472, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38772262

RESUMO

Interface engineering and vacancy engineering play an important role in the surface and electronic structure of nanomaterials. The combination of the two provides a feasible way for the development of efficient photocatalytic materials. Here, we use glutathione (GSH) as a coordination molecule to design a series of CuxS nanomaterials (CuxS-GSH) rich in sulfur vacancies using a simple ultrasonic-assisted method. Interface engineering can induce amorphous structure in the crystal while controlling the formation of porous surfaces of nanomaterials, and the formation of a large number of random orientation bonds further increases the concentration of sulfur vacancies in the crystal structure. This study shows that interface engineering and vacancy engineering can enhance the light absorption ability of CuxS-GSH nanomaterials from the visible to the near-infrared region, improve the efficiency of charge transfer between CuxS groups, and promote the separation and transfer of optoelectronic electron-hole pairs. In addition, a higher specific surface area can produce a large number of active sites, and the synergistic and efficient photothermal conversion efficiency (58.01%) can jointly promote the better photocatalytic performance of CuxS-GSH nanomaterials. Based on the excellent hot carrier generation and photothermal conversion performance of CuxS-GSH under illumination, it exhibits an excellent ability to mediate the production of reactive oxygen species (ROS) through peroxide cleavage and has excellent peroxidase activity. Therefore, CuxS-GSH has been successfully developed as a nanoenzyme platform for detecting tannic acid (TA) content in tea, and convenient and rapid detection of tannic acid is achieved through the construction of a multi-model strategy. This work not only provides a new way to enhance the enzyme-like activity of nanomaterials but also provides a new prospect for the application of interface engineering and vacancy engineering in the field of photochemistry.

2.
Membranes (Basel) ; 14(4)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38668113

RESUMO

In recent years, anion exchange membranes (AEMs) have aroused widespread interest in hydrogen production via water electrolysis using renewable energy sources. The two current commercial low-temperature water electrolysis technologies used are alkaline water electrolysis (AWE) and proton exchange membrane (PEM) water electrolysis. The AWE technology exhibited the advantages of high stability and increased cost-effectiveness with low hydrogen production efficiency. In contrast, PEM water electrolysis exhibited high hydrogen efficiency with low stability and cost-effectiveness, respectively. Unfortunately, the major challenges that AEMs, as well as the corresponding ion transportation membranes, including alkaline hydrogen separator and proton exchange membranes, still face are hydrogen production efficiency, long-term stability, and cost-effectiveness under working conditions, which exhibited critical issues that need to be addressed as a top priority. This review comprehensively presented research progress on AEMs in recent years, providing a thorough understanding of academic studies and industrial applications. It focused on analyzing the chemical structure of polymers and the performance of AEMs and established the relationship between the structure and efficiency of the membranes. This review aimed to identify approaches for improving AEM ion conductivity and alkaline stability. Additionally, future research directions for the commercialization of anion exchange membranes were discussed based on the analysis and assessment of the current applications of AEMs in patents.

3.
Int J Biol Macromol ; 269(Pt 2): 131852, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679253

RESUMO

Particulates and organic toxins, such as microplastics and dye molecules, are contaminants in industrial wastewater that must be purified due to environmental and sustainability concerns. Carboxylated cellulose acetate (CTA-COOH) nanofibrous membranes were fabricated using electrospinning followed by an innovative one-step surface hydrolysis/oxidation replacing the conventional two-step reactions. This approach offers a new pathway for the modification strategy of cellulose-based membranes. The CTA-COOH membrane was utilized for the removal of particulates and cationic dyes through filtration and adsorption, respectively. The filtration performance of the CTA-COOH nanofibrous membrane was carried out; high separation efficiency and low pressure drop were achieved, in addition to the high filtration selectivity against 0.6-µm and 0.8-µm nanoparticles. A cationic Bismarck Brown Y, was employed to challenge the adsorption capability of the CTA-COOH nanofibrous membrane, where the maximum adsorption capacity of the membrane for BBY was 158.73 mg/g. The self-standing CTA-COOH membrane could be used to conduct adsorption-desorption for 17 cycles with the regeneration rate as high as 97.0 %. The CTA-COOH nanofibrous membrane has excellent mechanical properties and was employed to manufacture a spiral wound adsorption cartridge, which exhibited remarkable separation efficiency in terms of treated water volume, which was 5.96 L, and retention rate, which was 100 %.


Assuntos
Celulose , Corantes , Membranas Artificiais , Nanofibras , Poluentes Químicos da Água , Celulose/química , Celulose/análogos & derivados , Nanofibras/química , Corantes/química , Corantes/isolamento & purificação , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Material Particulado/química , Filtração/métodos , Águas Residuárias/química
4.
Nano Lett ; 24(7): 2142-2148, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38323571

RESUMO

Spins confined to point defects in atomically thin semiconductors constitute well-defined atomic-scale quantum systems that are being explored as single-photon emitters and spin qubits. Here, we investigate the in-gap electronic structure of individual sulfur vacancies in molybdenum disulfide (MoS2) monolayers using resonant tunneling scanning probe spectroscopy in the Coulomb blockade regime. Spectroscopic mapping of defect wave functions reveals an interplay of local symmetry breaking by a charge-state-dependent Jahn-Teller lattice distortion that, when combined with strong (≃100 meV) spin-orbit coupling, leads to a locking of an unpaired spin-1/2 magnetic moment to the lattice at low temperature, susceptible to lattice strain. Our results provide new insights into the spin and electronic structure of vacancy-induced in-gap states toward their application as electrically and optically addressable quantum systems.

5.
Membranes (Basel) ; 13(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37505017

RESUMO

To achieve high throughput, low-pressure drops, and high adsorption capacity of Cr(VI) and Pb(II) in industrial wastewater treatment, cellulose membranes containing cationic and anionic groups were fabricated, respectively. In this process, cost-effective cotton fabrics were oxidized using sodium periodate, followed by quaternary ammonium or sulfonation modifications. The chemical composition, surface morphology, and thermal and mechanical properties of the cellulose membranes were investigated by ATR-FTIR, solid-state NMR, SEM, TGA, and tensile experiments. Quaternary ammonium, aldehyde, and sulfonate groups were distributed on the cationic/anionic cellulose fibers as adsorption sites, which issue remarkable adsorption capability to the cellulose membranes. The highly toxic Cr(VI) and Pb(II) ions were used to challenge the adsorption capacity of the cationic and anionic cellulose membranes, respectively. The maximum adsorption capacities of Cr(VI) and Pb(II) ions were 61.7 and 63.7 mg/g, respectively, suggested by Langmuir isotherms, kinetics, and thermodynamics in the static experiments. The dynamic adsorption capability of cationic cellulose membranes against Cr(VI) ions was determined and compared with that of commercially available anionic-exchange membranes. Spiral wound filtration cartridges were fabricated by cationic and anionic cellulose membranes, respectively, and were used to adsorb Cr(VI) and Pb(II) from lab-made wastewater, respectively. The cationic cellulose cartridge can purify 4.4 L of wastewater containing 1.0 mg/L of Cr(VI) ions with a 100% removal ratio, while the pressure drop was retained at 246 Pa. Similarly, the anionic cellulose cartridge exhibited even more impressive adsorption capability; the removal ratio against Pb(II) was 99% when 8.6 L of 1.0 mg/L of Pb(II) ions containing wastewater was treated, and the pressure drop was retained at 234 Pa. A composite cartridge fabricated by the integration of cationic and anionic cellulose membranes was successfully employed to purify the wastewater containing Cr(VI) and Pb(II) simultaneously. The possible adsorption mechanism was proposed, and the recycling ability of the cellulose membranes was also discussed.

6.
Nano Lett ; 23(13): 6171-6177, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37363814

RESUMO

Spins confined to atomically thin semiconductors are being actively explored as quantum information carriers. In transition metal dichalcogenides (TMDCs), the hexagonal crystal lattice gives rise to an additional valley degree of freedom with spin-valley locking and potentially enhanced spin life and coherence times. However, realizing well-separated single-particle levels and achieving transparent electrical contact to address them has remained challenging. Here, we report well-defined spin states in a few-layer MoS2 transistor, characterized with a spectral resolution of ∼50 µeV at Tel = 150 mK. Ground state magnetospectroscopy confirms a finite Berry-curvature induced coupling of spin and valley, reflected in a pronounced Zeeman anisotropy, with a large out-of-plane g-factor of g⊥ ≃ 8. A finite in-plane g-factor (g∥ ≃ 0.55-0.8) allows us to quantify spin-valley locking and estimate the spin-orbit splitting 2ΔSO ∼ 100 µeV. The demonstration of spin-valley locking is an important milestone toward realizing spin-valley quantum bits.

7.
Mater Horiz ; 10(8): 3162-3173, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37232288

RESUMO

The development of high energy density and long cycle lifespan aqueous zinc ion batteries is hindered by the limited cathode materials and serious zinc dendrite growth. In this work, a defect-rich VS2 cathode material is manufactured by in situ electrochemical defect engineering under high charge cut-off voltage. Owing to the rich abundant vacancies and lattice distortion in the ab plane, the tailored VS2 can unlock the transport path of Zn2+ along the c-axis, enabling 3D Zn2+ transport along both the ab plane and c-axis, and reduce the electrostatic interaction between VS2 and zinc ions, thus achieving excellent rate capability (332 mA h g-1 and 227.8 mA h g-1 at 1 A g-1 and 20 A g-1, respectively). The thermally favorable intercalation and 3D rapid transport of Zn2+ in the defect-rich VS2 are verified by multiple ex situ characterizations and density functional theory (DFT) calculations. However, the long cycling stability of the Zn-VS2 battery is still unsatisfactory due to the Zn dendrite issue. It can be found that the introduction of an external magnetic field enables changing the movement of Zn2+, suppressing the growth of zinc dendrites, and resulting in enhanced cycling stability from about 90 to 600 h in the Zn||Zn symmetric cell. As a result, a high-performance Zn-VS2 full cell is realized by operating under a weak magnetic field, which shows an ultralong cycle lifespan with a capacity of 126 mA h g-1 after 7400 cycles at 5 A g-1, and delivers the highest energy density of 304.7 W h kg-1 and maximum power density of 17.8 kW kg-1.

8.
ACS Appl Mater Interfaces ; 15(21): 26199-26214, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37192294

RESUMO

A nanofibrous composite reverse osmosis (RO) membrane with a polyamide barrier layer containing interfacial water channels was fabricated on an electrospun nanofibrous substrate via an interfacial polymerization process. The RO membrane was employed for desalination of brackish water and exhibited enhanced permeation flux as well as rejection ratio. Nanocellulose was prepared by sequential oxidations of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and sodium periodate systems and surface grafting with different alkyl groups including octyl, decanyl, dodecanyl, tetradecanyl, cetyl, and octadecanyl groups. The chemical structure of the modified nanocellulose was verified subsequently by Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA), and solid NMR measurements. Two monomers, trimesoyl chloride (TMC) and m-phenylenediamine (MPD), were employed to prepare a cross-linked polyamide matrix, i.e., the barrier layer of the RO membrane, which integrated with the alkyl groups-grafted nanocellulose to build up interfacial water channels via interfacial polymerization. The top and cross-sectional morphologies of the composite barrier layer were observed by means of scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM) to verify the integration structure of the nanofibrous composite containing water channels. The aggregation and distribution of water molecules in the nanofibrous composite RO membrane verified the existence of water channels, demonstrated by molecular dynamics (MD) simulations. The desalination performance of the nanofibrous composite RO membrane was conducted and compared with that of commercially available RO membranes in the processing of brackish water, where 3 times higher permeation flux and 99.1% rejection ratio against NaCl were accomplished. This indicated that the engineering of interfacial water channels in the barrier layer could substantially increase the permeation flux of the nanofibrous composite membrane while retaining the high rejection ratio as well, i.e., to break through the trade-off between permeation flux and rejection ratio. Antifouling properties, chlorine resistance, and long-term desalination performance were also demonstrated to evaluate the potential applications of the nanofibrous composite RO membrane; remarkable durability and robustness were achieved in addition to 3 times higher permeation flux and a higher rejection ratio against commercial RO membranes in brackish water desalination.

9.
Small ; 19(25): e2207998, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929331

RESUMO

As the new generation of energy storage systems, the flexible battery can effectively broaden the application area and scope of energy storage devices. Flexibility and energy density are the two core evaluation parameters for the flexible battery. In this work, a flexible VS2 material (VS2 @CF) is fabricated by growing the VS2 nanosheet arrays on carbon foam (CF) using a simple hydrothermal method. Benefiting from the high electric conductivity and 3D foam structure, VS2 @CF shows an excellent rate capability (172.8 mAh g-1 at 5 A g-1 ) and cycling performance (130.2 mAh g-1 at 1 A g-1 after 1000 cycles) when it served as cathode material for aqueous zinc-ion batteries. More importantly, the quasi-solid-state battery VS2 @CF//Zn@CF assembled by the VS2 @CF cathode, CF-supported Zn anode, and a self-healing gel electrolyte also exhibits excellent rate capability (261.5 and 149.8 mAh g-1 at 0.2 and 5 A g-1 , respectively) and cycle performance with a capacity of 126.6 mAh g-1 after 100 cycles at 1 A g-1 . Moreover, the VS2 @CF//Zn@CF full cell also shows good flexible and self-healing properties, which can be charged and discharged normally under different bending angles and after being destroyed and then self-healing.

10.
Entropy (Basel) ; 25(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36832719

RESUMO

This paper proposes an encryption scheme for high pixel density images. Based on the application of the quantum random walk algorithm, the long short-term memory (LSTM) can effectively solve the problem of low efficiency of the quantum random walk algorithm in generating large-scale pseudorandom matrices, and further improve the statistical properties of the pseudorandom matrices required for encryption. The LSTM is then divided into columns and fed into the LSTM in order for training. Due to the randomness of the input matrix, the LSTM cannot be trained effectively, so the output matrix is predicted to be highly random. The LSTM prediction matrix of the same size as the key matrix is generated based on the pixel density of the image to be encrypted, which can effectively complete the encryption of the image. In the statistical performance test, the proposed encryption scheme achieves an average information entropy of 7.9992, an average number of pixels changed rate (NPCR) of 99.6231%, an average uniform average change intensity (UACI) of 33.6029%, and an average correlation of 0.0032. Finally, various noise simulation tests are also conducted to verify its robustness in real-world applications where common noise and attack interference are encountered.

11.
Adv Sci (Weinh) ; 10(4): e2203552, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36504360

RESUMO

As a promising cathode material of sodium-ion batteries, Na3 V2 (PO4 )3 (NVP) has attracted extensive attention in recent years due to its high stability and fast Na+ ion diffusion. However, the reversible capacity based on the two-electron reaction mechanism is not satisfactory limited by the inactive M1 lattice sites during the insertion/extraction process. Herein, self-supporting 3D porous NVP materials with different crystallinity are fabricated on carbon foam substrates by a facile electrostatic spray deposition method. The V5+ /V4+ redox couple is effectively activated and the three-electron reactions are realized in NVP for sodium storage by a proper crystallinity tuning. In a disordered NVP sample, an ultra-high specific capacity of 179.6 mAh g-1 at 0.2 C is achieved due to the coexistence of redox reactions of the V4+ /V3+ and V5+ /V4+ couples. Moreover, a pseudocapacitive charge storage mechanism induced by the disordered structure is first observed in the NVP electrode. An innovative model is given to understand the disorder-induced-pseudocapacitance phenomenon in this polyanion cathode material.

12.
Entropy (Basel) ; 24(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36554188

RESUMO

We focus on the problem that the Grover algorithm is not suitable for the completely unknown proportion of target solutions. Considering whether the existing quantum classifier used by the current quantum neural network (QNN) to complete the classification task can solve the problem of the classical classifier, this paper proposes a binary quantum neural network classifical model based on an optimized Grover algorithm based on partial diffusion. Trial and error is adopted to extend the partial diffusion quantum search algorithm with the known proportion of target solutions to the unknown state, and to apply the characteristics of the supervised learning of the quantum neural network to binary classify the classified data. Experiments show that the proposed method can effectively retrieve quantum states with similar features. The test accuracy of BQM retrieval under the depolarization noise at the 20th period can reach 97% when the depolarization rate is 0.1. It improves the retrieval accuracy by about 4% and 10% compared with MSE and BCE in the same environment.

13.
ACS Appl Mater Interfaces ; 14(34): 38875-38886, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35976057

RESUMO

Transition metal nitrides (TMNs) with high specific capacity and electric conductivity have drawn considerable attention as electrode materials of lithium-ion batteries (LIBs). However, the cycling stability of most TMNs is not satisfactory, which was caused by the large volume variation during cycles due to their intrinsic conversion reaction mechanism. Herein, by rational design, a much stable tremella-like Ni0.2Mo0.8N/Ni3N heterostructure with amorphous Ni0.2Mo0.8N wrapped layer has been fabricated. The Ni3N particles worked as pillars to support the Ni0.2Mo0.8N material as well as conductive medium to facilitate ionic and electronic transport. The amorphous layer can relieve the structural stress of Ni0.2Mo0.8N during cycles. Moreover, an exotic intercalation-type reaction mechanism in the ternary nitride Ni0.2Mo0.8N was revealed by a series ex situ and in situ characterization. Profiting from these advantages, the Ni0.2Mo0.8N/Ni3N heterostructure anode displays an outstanding electrochemical performance with a high initial reversible discharge capacity of 1001.6 mA h g-1 at 0.1 A g-1, excellent cycle stability of 695.5 mA h g-1 at 2 A g-1 after 600 cycles, and superior rate capability of 595.3 mA h g-1 at a high current density of 5 A g-1. This work provides a new insight for designing high efficiency LIBs based on intercalation reaction for practical applications.

14.
Sci Rep ; 12(1): 14253, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995941

RESUMO

Aiming at solving the trouble that digital image information is easily intercepted and tampered during transmission, we proposed a color image encryption scheme based on alternate quantum random walk and controlled Rubik's Cube transformation. At the first, the color image is separated into three channels: channel R, channel G and channel B. Besides, a random sequence is generated by alternate quantum walk. Then the six faces of the Rubik's Cube are decomposed and arranged in a specific order on a two-dimensional plane, and each pixel of the image is randomly mapped to the Rubik's Cube. The whirling of the Rubik's Cube is controlled by a random sequence to realize image scrambling and encryption. The scrambled image acquired by Rubik's Cube whirling and the random sequence received by alternate quantum walk are bitwise-XORed to obtain a single-channel encrypted image. Finally the three-channel image is merged to acquire the final encrypted image. The decryption procedure is the reverse procedure of the encryption procedure. The key space of this scheme is theoretically infinite. After simulation experiments, the information entropy after encryption reaches 7.999, the NPCR is 99.5978%, and the UACI is 33.4317%. The encryption scheme with high robustness and security has a excellent encryption effect which is effective to resist statistical attacks, force attacks, and other differential attacks.

15.
Entropy (Basel) ; 24(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35626493

RESUMO

This paper proposes an image encryption scheme based on a discrete-time alternating quantum walk (AQW) and the advanced encryption standard (AES). We use quantum properties to improve the AES algorithm, which uses a keystream generator related to AQW parameters to generate a probability distribution matrix. Some singular values of the matrix are extracted as the key to the AES algorithm. The Rcon of the AES algorithm is replaced with the elements of the probability distribution matrix. Then, the ascending order of the size of the clone probability distribution matrix scrambles the mapping rules of the S-box and ShiftRow transformations in the AES algorithm. The algorithm uses a probability distribution matrix and plaintext XOR operation to complete the preprocessing and uses the modified AES algorithm to complete the encryption process. The technology is based on simulation verification, including pixel correlation, histograms, differential attacks, noise attacks, information entropy, key sensitivity, and space. The results demonstrate a remarkable encryption effect. Compared with other improved AES algorithms, this algorithm has the advantages of the original AES algorithm and improves the ability to resist correlation attacks.

16.
Int J Implant Dent ; 8(1): 15, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378661

RESUMO

AIM: The aim of the study was to assess the 5-year cumulative survival rate of implant-based dental rehabilitation following maxillofacial reconstruction with a vascularized bone flap and to investigate the potential risk factors which might influence the survival rate. MATERIALS AND METHODS: A retrospective cohort study was designed. Inclusion criteria involved 18 years old or above patients with the availability of clinical and radiological data and a minimum follow-up 1 year following implant placement. The cumulative survival rate was analyzed by Kaplan-Meier curves and the influential risk factors were assessed using univariate log-rank tests and multivariable Cox-regression analysis. RESULTS: 151 implants were assessed in 40 patients with a mean age of 56.43 ± 15.28 years at the time of implantation. The mean number of implants placed per patient was 3.8 ± 1.3 with a follow-up period of 50.0 ± 32.0 months. The cumulative survival at 1-, 2- and 5-years was 96%, 87%, and 81%. Patients with systemic diseases (HR = 3.75, 95% CI 1.65-8.52; p = 0.002), irradiated flap (HR = 2.27, 95% CI 1.00-5.17; p = 0.05) and poor oral hygiene (HR = 11.67; 95% CI 4.56-29.88; p < 0.0001) were at a significantly higher risk of implant failure. CONCLUSION: The cumulative implant survival rate was highest at 1st year followed by 2nd and 5th year, indicating that the risk of implant failure increased over time. Risk indicators that seem to be detrimental to long-term survival include poor oral hygiene, irradiated flap and systemic diseases.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Adolescente , Adulto , Idoso , Prótese Dentária Fixada por Implante , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Retalhos Cirúrgicos
17.
ACS Appl Mater Interfaces ; 14(9): 11937-11949, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35229603

RESUMO

There is considerable interest in the pH-dependent, switchable, biocatalytic properties of cerium oxide (CeO2) nanoparticles in biomedicine, where these materials exhibit beneficial antioxidant activity against reactive oxygen species (ROS) at a basic physiological pH but cytotoxic prooxidant activity in an acidic cancer cell pH microenvironment. While the general characteristics of the role of oxygen vacancies are known, the mechanism of their action at the atomic scale under different pH conditions has yet to be elucidated. The present work applies density functional theory (DFT) calculations to interpret, at the atomic scale, the pH-induced behavior of the stable {111} surface of CeO2 containing oxygen vacancies. Analysis of the surface-adsorbed media species reveals the critical role of pH on the interaction between ROS (•O2- and H2O2) and the defective CeO2 {111} surface. Under basic conditions, the superoxide dismutase (SOD) and catalase (CAT) biomimetic reactions can be performed cyclically, scavenging and decomposing ROS to harmless products, making CeO2 an excellent antioxidant. However, under acidic conditions, the CAT biomimetic reaction is hindered owing to the limited reversibility of Ce3+ ↔ Ce4+ and formation ↔ annihilation of oxygen vacancies. A Fenton biomimetic reaction (H2O2 + Ce3+ → Ce4+ + OH- + •OH) is predicted to occur simultaneously with the SOD and CAT biomimetic reactions, resulting in the formation of hydroxyl radicals, making CeO2 a cytotoxic prooxidant.


Assuntos
Biocatálise , Biomimética , Cério/química , Teoria da Densidade Funcional , Nanopartículas/química , Antioxidantes/química , Catalase/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Oxidantes/química , Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/química
18.
Clin Oral Investig ; 26(3): 2269-2279, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35013781

RESUMO

OBJECTIVE: The aim of this systematic review was to provide evidence related to the association between non-antiresorptive medications and MRONJ. MATERIALS AND METHODS: The following three electronic databases were screened: PubMed, EMBASE, and Web of Science from December 2020 until April 2021. Two reviewers independently performed the study selection, data extraction, and quality assessment of the included studies. The Newcastle-Ottawa Scale (NOS) was used for assessing the risk of bias. A meta-analysis was performed for assessing the relationship between MRONJ and non-antiresorptive medications. RESULTS: The search strategy retrieved 996 articles. Following removal of duplicates, title, and abstract screening and full-text reading, 58 publications were eligible to be included in the review. A total of 867 cases of MRONJ were included (33% female, 55% male, 12% no gender reported). The mean age of the patients when MRONJ was diagnosed was 61 years (range 19-100 years) and the average time of diagnosis was 10 months following non-antiresorptive drug therapy. Patients with a history of corticosteroids (0.61, 95% CI 0.39, 0.82, p = < 0.001) and chemotherapy (0.59, 95% CI 0.51, 0.67, p = < 0.001) showed the highest significant effect size (ED) compared to the control group for MRONJ occurrence. CONCLUSION: A significant association existed between MRONJ and non-antiresorptive drugs. However, considering limited evidence, findings should be interpreted with caution. CLINICAL RELEVANCE: The non-antiresorptive drugs might allow the dentist to apply the principle of "drug holiday" following concurrence from the drug prescribing clinician. PROSPERO REGISTRATION NUMBER: CRD42020173891.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Conservadores da Densidade Óssea/efeitos adversos , Criança , Pré-Escolar , Difosfonatos/efeitos adversos , Feminino , Humanos , Lactente , Masculino
19.
J Stomatol Oral Maxillofac Surg ; 123(1): 44-50, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321252

RESUMO

PURPOSE: This study aims to assess the survival rate of oral squamous cell carcinoma (OSCC) patients following immediate mandibular reconstruction with vascularized fibula flap (VFF) and to identify risk factors influencing the overall survival rate and postoperative outcomes. PATIENTS AND METHODS: Patients suitable for the inclusion criterion diagnosed and treated between January 1996 till June 2019 for OSCC were retrospectively reviewed (n = 74). Potential risk factors and postoperative outcomes were recorded and analyzed. RESULTS: The overall cumulative survival rate of patients was 0.52 at the end of 5th year. Overall, advanced pN stage (p = 0.0422), poor tumor differentiation (p < 0.0001), positive/close surgical margins (p = 0.0209), vascular invasion (p = 0.0395), perineural invasion (p = 0.0022) and tumor recurrence (p = 0.0232) were significantly related to a decreased cumulative survival. Tumor recurrence was significantly correlated with involvement of positive/close surgical margins, moderate (p = 0.0488), poor-differentiated tumors (p = 0.202), extracapsular spread (p = 0.0465), computer-assisted surgery (p = 0.0014) and early complications (p = 0.0224). Pain was significantly associated with the extracapsular spread (p = 0.0353) and early complications (p = 0.0127). CONCLUSION: The five-year survival rate of advanced OSCC patients after segmental mandibulectomy with fibula free-flap reconstruction was 52.4%. Clinical/pathological risk factors such as the pN stage, tumor differentiation, surgical margins, vascular invasion, perineural invasion, tumor recurrence significantly influenced the overall cumulative survival rate.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Fíbula/patologia , Fíbula/cirurgia , Humanos , Mandíbula/patologia , Mandíbula/cirurgia , Osteotomia Mandibular/efeitos adversos , Margens de Excisão , Neoplasias Bucais/diagnóstico , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Análise de Sobrevida
20.
Opt Express ; 29(18): 28338-28351, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34614967

RESUMO

As an important information medium, the digital image exists widely on the Internet. Quantum walks have the property of encrypting information. For the eneryption problem of optical digital images, an encryption scheme based on discrete cosine transform (DCT) and alternate quantum walks (AQW) is proposed in this paper. First, we use AQW and XOR operation to preprocess images in the spatial domain. Then, AQW are used to generate two random phase masks which can operate the preprocessed image and the DCT image, respectively. Finally, the encrypted image is obtained by using discrete cosine inverse exchange. The control parameters of AQW can replace the random phase mask as the key in the encryption and decryption process, so it is convenient for key management and transmission. The experimental simulation carried out the analysis of the image pixel histogram, the correlation of adjacent pixels, the robustness against noise and the sensitivity of secret keys, the results show that the image encryption method has strong security.

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