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In view of dual watermarking algorithm for dual two value image watermarking, the watermark information there is a gray image watermarking in the expression is obviously insufficient. The proposed embedded in the carrier image on the dual watermark includes a two watermark image and a gray image watermarking algorithm, the persuasive power while maintaining the original two values of the watermark robustness at the same time, improve the watermark information. In order to balance the robustness and invisibility of watermarking algorithm, this paper analyzes the embedding position and strategy of transform domain algorithms, the DC coefficient in the carrier image is divided into blocks of DCT spectrum and spectrum on the combination of DWT coefficient method and the advantage of embedded dual watermarking, and use the NEC characteristic of the algorithm is improved adaptive based on the embedded mode. The gray image watermark bit plane decomposition compression high four bit plane information as watermarking, in reducing the original watermark loading and enhance the overall strength of self recovery system. This paper from the working principle, classification of digital watermarking, attack types, performance index, evaluation method and uses six aspects were introduced to the digital watermarking technology. Simulation study of a digital image watermarking algorithm based on DCT transform and Arnold transform, the algorithm's imperceptibility, robustness and security are analyzed, the algorithm for embedding process. [ABSTRACT FROM AUTHOR]

In this work, the functional groups on acid-treated and heat-treated carbon nanotubes (CNTs) were investigated by Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy. The morphology of the TiO2 particles decorated on the two kinds of CNTs was also studied, respectively. The results indicated that the functional groups could adsorb [image omitted] ions in the aqueous solution due to their electronegativity and benefit for the well dispersion of TiO2.The mechanism of TiO2 well dispersion on CNTs surface was also discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this study, new nanoscale photocatalyst based on silver and CNTs/TiO2 was successfully prepared by photoreduction method. The prepared Ag-CNTs/TiO2 was characterized by TEM, XRD and XPS. The photocatalytic activity was also evaluated by photocatalytic degradation of Reactive Brilliant Red X-3B dye. The results indicated that the photocatalytic efficiency of CNTs/TiO2 increased in the presence of Ag nanoparticles and the photocatalysis reaction followed a first order kinetics. The kinetic constant of Ag-CNTs/TiO2 for dye degradation was nearly 1.2 times than that of CNTs/TiO2, which indicated decorating Ag nanoparticles on CNTs/TiO2 could enhance the photocatalytic ability. [Copyright &y& Elsevier]

Abstract: In this paper, nanosize titanium dioxide (TiO2) deposited on pristine and acid treated carbon nanotubes (CNTs) were prepared by a modified sol–gel method. The nanoscale materials were extensively characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR) and Raman spectra. The results indicated that about 6.8nm TiO2 nanoparticles were successfully deposited on acid-treated CNTs surface homogeneously and densely, which was smaller than TiO2 coated on pristine CNTs. The surface state of CNTs was a critical factor in obtaining a homogeneous distribution of nanoscale TiO2 particles. Acid oxidization could etch the surface of CNTs and introduce functional groups, which were beneficial to controllable homogeneous deposition. The TiO2 coated on acid-treated CNTs was used as photocatalyst for Reactive Brilliant Red X-3B dye degradation under UV irradiation, which showed higher efficiency than that of TiO2 coated on pristine CNTs and commercial photocatalyst P25. [Copyright &y& Elsevier]

Abstract: In this paper, we prepared carbon nanotube (CNT) electrodes with polytetrafluoroethylene (PTFE) as binders to adsorb NaCl from water. The electrodes were characterized using scanning electron micrograph (SEM), nitrogen adsorption and cyclic voltammetry. The adsorption/electrosorption rate and capacity of CNT electrodes with different bias potentials were measured, and the electrosorption isotherms and kinetics were also investigated. The results showed that electrosorption can effectively increase the adsorption capacity and rate of NaCl on CNT electrodes. The adsorption/electrosorption of NaCl on CNT electrodes followed Langmuir isotherms and the pseudo-first-order adsorption kinetics. The equilibrium adsorption capacity at 1.2V was 9.35mg/g, which was nearly eight times higher than that at 0V. Compared with the adsorption rate at 0V, the adsorption rate at 1.2V was increased by 58.9%. The enhancement of capacity and rate may be due to the forming an electric double layer on the surface of CNT electrodes in the solution. [Copyright &y& Elsevier]

The individual and competitive adsorption capacities of Pb2+, Cu2+ and Cd2+ by nitric acid treated multiwalled carbon nanotubes (CNTs) were studied. The maximum sorption capacities calculated by applying the Langmuir equation to single ion adsorption isotherms were 97.08 mg/g for Pb2+, 24.49 mg/g for Cu2+ and 10.86 mg/g for Cd2+ at an equilibrium concentration of 10 mg/l. The competitive adsorption studies showed that the affinity order of three metal ions adsorbed by CNTs is Pb2+>Cu2+>Cd2+. The Langmuir adsorption model can represent experimental data of Pb2+ and Cu2+ well, but does not provide a good fit for Cd2+ adsorption data. The effects of solution pH, ionic strength and CNT dosage on the competitive adsorption of Pb2+, Cu2+ and Cd2+ ions were investigated. The comparison of CNTs with other adsorbents suggests that CNTs have great potential applications in environmental protection regardless of their higher cost at present. [Copyright &y& Elsevier]

Objective: Recent evidence suggests the involvement of senescence and inflammation in abdominal aortic aneurysm (AAA). Considering the role of sirtuin-1 (SIRT1) in delaying senescence, we aimed to preliminarily investigate the potential mechanism underlying the effects of SIRT1 in senescence and inflammation during AAA., Material and Methods: A cell AAA model was established using angiotensin II (Ang II) as the inducer, which was applied to treat human aortic vascular smooth muscle cells (HASMCs). The senescence and cell cycle of treated HASMCs were evaluated based on senescence-associated (SA)-b-galactosidase (b-gal) assay and flow cytometry, respectively. The levels of inflammatory cytokines and proteins related to senescence-associated secretory phenotype (SASP), along with nuclear factor-kappa B (NF-kB) and mitogen-activated protein kinases (MAPK) pathways, as well as SIRT1, were gauged. The correlation between SIRT1 and NF-kB and MAPK pathway-related proteins was further estimated., Results: In Ang II-treated HASMCs, reduced SIRT1 and B-cell lymphoma-2 levels yet increased levels of SASP-related proteins P16 and P21, inflammatory cytokines, as well as Bax and caspases were all visible. In the meantime, Ang II exposure enhanced the number of b-gal-positive HASMCs and promoted cell cycle arrest. SIRT1 was also repressed following Ang II treatment and negatively correlated with NF-kB and MAPK pathway-related proteins ( P < 0.05). Furthermore, the overexpression of SIRT1 diminished the levels of SASP-related proteins and reduced the phosphorylation of extracellular regulated kinase 1/2 and P65 in Ang II-treated HASMCs ( P < 0.05)., Conclusion: Taken together, our results indicate that SIRT1 overexpression attenuates the inflammatory and senescent responses of HASMCs in the Ang II-induced AAA cell model. This finding suggests that SIRT1 can be a highly promising target for clinical treatment of AAA., Competing Interests: The authors declare no conflict of interest, (© 2024 The Author(s). Published by Scientific Scholar.)

Rationale: Dissection of the cervical arteries is the most commonly identified cause of stroke in young patients. This report helps to investigate the etiology, diagnosis, and treatment of cervical artery dissection (CAD)., Patient Concerns: A 40-year-old female presented with a 3-week history of right carotid artery dissection due to a fall. The patient was admitted to the local hospital 3 weeks ago with a right neck impingement after a fall, and presented with right neck pain. The local hospital CT scan showed a dissection of the middle segment of the right common carotid artery., Diagnoses: The patient clinical manifestations and imaging tests confirmed that right carotid artery dissection., Interventions: Medical treatment with antiplatelet failed, and the CT scan showed progression of dissection. Carotid endarterectomy (CEA) was performed, and the prognosis is good., Outcomes: This patient was followed up at 1 and 6 months after the operation, CT scan showed the original stenotic vessels returned to standard diameter., Lessons: Diagnosis of CAD mainly depends on clinical manifestations and imaging. we recommend that clinicians can prescribe either anticoagulants or antiplatelet therapy. CAD can be effectively treated by surgical reconstruction, if medical treatment with anticoagulation or antiplatelet fails or if carotid aneurysms and/or high-grade carotid stenosis persisted or have newly developed., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: For patients with varicose veins, the goal is to relieve pain and swelling, reduce the severity of edema, improve skin changes, and heal ulcers associated with venous disease. Compression therapy is the cornerstone of their management. Several studies have shown that wearing an elastic bandage for the first 24 h and then a compression stocking for a week can effectively reduce the pain after thermal ablation. However, in clinical practice, patient compliance with this treatment could be better, considering difficulties in pulling up and removing the compression stocking, tightness, and skin irritation because these must be worn for a prolonged period. A potential solution to battling these barriers is short-term compression therapy. Besides, the effect and necessity of wearing compression stockings after thermal ablation have been questioned. Based on current clinical experience and limited evidence, although some scholars have suggested that compression therapy may be an unnecessary adjunctive therapy after thermal ablation, there is still a great deal of uncertainty in the absence of compression therapy after thermal ablation compared to compression therapy. Therefore, we advocate further research to evaluate the clinical effect of short-term postoperative compression therapy. Furthermore, well-designed randomized controlled trials are needed., Methods: A prospective, multicenter, non-inferiority randomized controlled trial is designed to evaluate the non-inferiority of target vein occlusion rate at 3 months. Three hundred and sixty patients will be randomly assigned in a 1:1 ratio to one of the following treatments: (A) 3 M™ Coban™ elastic bandage for 48 h or (B) 3 M™ Coban™ elastic bandage for the first 24 h and then a class II compression full-length stocking (23-32 mm Hg) for 1 week. The two groups will be compared on several variables, including target vein occlusion rate at 3 months (primary outcome indicator), pain, quality of life, clinical severity of varicose veins, postoperative complications, time to return to regular work, and compliance., Discussion: Suppose the effect of the 3 M™ Coban™ elastic bandage for 48 h proves to be non-inferior to long-term compression therapy. In that case, this short-term treatment may contribute to a future update of clinical guidelines for compression therapy after thermal ablation of varicose veins, resulting in higher patient compliance and better postoperative quality of life., Trial Registration: Clinical Trials NCT05840991 . Registered on May 2023., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Ferritin is an endogenous protein which is self-assembled by 24 subunits into a highly uniform nanocage structure. Due to the drug-encapsulating ability in the hollow inner cavity and abundant modification sites on the outer surface, ferritin nanocage has been demonstrated great potential to become a multi-functional nanomedicine platform. Its good biocompatibility, low toxicity and immunogenicity, intrinsic tumor-targeting ability, high stability, low cost and massive production, together make ferritin nanocage stand out from other nanocarriers. In this review, we summarized ferritin-based nanomedicine in field of disease diagnosis, treatment and prevention. The different types of drugs to be loaded in ferritin, as well as drug-loading methods were classified. The strategies for site-specific and non-specific functional modification of ferritin were investigated, then the application of ferritin for disease imaging, drug delivery and vaccine development were discussed. Finally, the challenges restricting the clinical translation of ferritin-based nanomedicines were analyzed., Competing Interests: Competing interests: The authors declare no competing financial interests., (© 2023 the author(s), published by De Gruyter, Berlin/Boston.)

The hypoxic tumor microenvironment and photodynamic therapy (PDT)-aggravated hypoxia compromise the anticancer efficacy of chemotherapy, immunotherapy, and PDT. Thus, sophisticated nanomedicines that can activate their anticancer capability in situ in response to specific stimuli need to be developed. This study aimed to construct a hybrid nanomedicine that activated chemotherapy by inducing hypoxia, which synergized with PDT to promote antitumor outcomes, contrary to the strategies focusing on reversing tumor hypoxia. The hybridization of a porphyrin metal-organic framework (MOF) and gold nanoparticles (AuNPs) enhanced the stability of the hybrid nanomedicine against the phosphate in blood, thereby preventing the premature drug release during blood circulation. The surface modification with polyethylene glycol (PEG) markedly increased the tumor accumulation of the hybrid MOF nanomedicine, which encapsulated a hypoxia-activated prodrug (tirapazamine, TPZ), by enhancing its colloidal stability and pharmacokinetics. The loaded TPZ was rapidly released from the nanomedicine in response to the concentrated intracellular phosphate after cellular uptake, and was then converted into a potent anticancer drug in a hypoxic microenvironment exacerbated by continuous O 2 consumption during PDT. In vitro and in vivo experiments demonstrated that the synergistic PDT and hypoxia-activated chemotherapy exhibited enhanced antitumor therapeutic efficiency and superior antimetastatic effect, and effectively ablated the tumor without recurrence. Therefore, the sophisticated nanomedicine reported here, which eliminated cancer cells by inducing a hypoxic tumor microenvironment, showed translational potential in future therapeutic development., (Copyright © 2022 Elsevier Inc. All rights reserved.)

With the rapid development of chromatographic stationary-phase preparation technology, various modified methods are becoming increasingly mature, mainly including direct surface chemical reactions, agglomeration, grafting, and hyperbranched modification. Among these methods, hyperbranched modification based on polycondensation has been popular with researchers since it was proposed, and it has been applied to the preparation of various anion exchangers. Dendrimers are a class of three-dimensional, highly ordered dendritic macromolecules with perfect structure, high degree of surface functionality, and unique physicochemical properties. Recently, they have also gradually been applied in various chromatographic stationary-phase modifications and are expected to improve the structure and separation performance of the stationary phase, because its structure is similar to those of hyperbranched polymers. This article mainly summarizes the applications of hyperbranched and poly amidoamine dendrimers using grafted modification methods in the preparation of the chromatographic stationary phase. Finally, the trends and promising prospects of this field are presented.