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Challenges exist regarding the bonding efficiency of polyaryletherketone (PAEK), a high-performance thermoplastic, attributed to its chemical inertness and hydrophobic surface, hindering effective bonding with resin-matrix cement. This research explored the impact of handheld nonthermal plasma (HNP), under varying operational parameters, on PAEK surface wettability and changes in bonding performance with cement. Three types of disc-shaped PEAK specimens were prepared, with surface treatments categorized as grinding, airborne-particle abrasion (APB), and HNP. Surface wettability was analyzed using a contact angle analyzer (n = 10). Specimens were bonded with resin cement and subjected to artificial aging tests: distilled water bath (NA), thermocycling, and highly accelerated stress tests (n = 10 for each test). Shear bond strength (SBS) was measured, failure modes were analyzed, and statistical analyses were conducted. The HNP markedly improved PAEK surface wettability, achieving superhydrophilicity (P < 0.05). This effect intensified with extended operation times (30 or 60 s) and reduced elapsed times (<30 s). HNP-treated PAEK exhibited higher SBS than APB (P < 0.05) and maintained bonding durability after artificial aging, particularly in ketone-enriched variants. Failure analysis revealed predominantly adhesive failure under APB–NA treatment, mixture failures under HNP–NA treatment and postaging, but no cohesive failure. The HNP device benefits dental settings by transforming the PAEK surface into superhydrophilic properties, thereby improving PAEK–cement bonding. It significantly enhances bond durability within 30 s of operation and after a 30 s elapsed period. It is noteworthy that ketone-enriched PAEK demonstrates markedly improved bonding performance. [ABSTRACT FROM AUTHOR]

This study investigated the effects of nonthermal Ar/O2 plasma on the osseointegration of titanium implants. Through 8 weeks' in vivo evaluation of implants inserted into femoral bones of male Sprague-Dawley rats, the new bone mineralization apposition rate (MAR) is increased by 1.87 and 2.14 times for implants of smooth machined (SM) and sand-blasted and acid-etched (SLA) after plasma treatment. The bone volume fraction (bone volume/total volume, BV/TV) and bone-implant contact (BIC) ratios are improved by 1.31, 1.26 times and 1.35, 1.15 times after 90 s plasma treatment. The improved hydrophilicity rather than implant surface morphology is believed to play a critical role for the osseointegration improvement. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have become an environmental and health threat to aquatic species and humans because they are small and can easily reach water bodies for municipal and agricultural uses. MPs have been traced in food commodities and products derived from animals and even found in bottles of drinking water. Current treatment techniques for permanently destroying MPs require high energy inputs and thus are generally cost-inefficient. Atmospheric cold plasma (ACP) is a low-cost energy-efficient technology to produce highly reactive species that can induce physicochemical changes in plastic polymers. This study, for the first time, used ACP as a novel method for MPs treatment. Polypropylene (PP) and low-density polyethylene (LDPE) were used to prepare model MPs. The effects of plasma working gas (oxygen, nitrogen, or their mixture) and post-ACP treatment storage (24 h) on MPs were studied. ACP treatments for 30 min successfully degraded both MPs, by 1.4–11.3% in weight. PP MPs had larger weight reduction than LDPE and the ACP of mixture gas was most effective. PP MPs also showed increased carbonyl index after treatments, to up to 6.89, indicating hydrolytic degradation. For LDPE MPs, oxygen ACP caused more oxidation, but storage did not have an enhancing effect. The results of physicochemical analyses indicated that MPs degradation by ACP was possibly mainly through oxidative and hydrolytic reactions, but further characterizations are needed. This study proves that ACP is a promising strategy to remediate MPs pollution, and thus has great potential for addressing the severe challenges of MPs that the food and agriculture sectors are currently facing. [Display omitted] • Cold plasma is applied to degrade microplastics in water for the first time. • Plasma treatments of 30 min effectively reduce microplastics weight by up to 11.3%. • Storage after plasma treatment can enhance microplastics degradation. • Possible mechanisms of microplastics degradation include oxidation and hydrolysis. [ABSTRACT FROM AUTHOR]

Background The use of a nonthermal plasma (NTP) jet in the treatment of living tissue has been the subject of considerable interest in the field of medical technology, and has the potential to reduce the recovery time of open wounds. We aimed to investigate the wound-healing process by clinical observation, blood tests, and expression of cell adhesion markers and reactive oxygen species in NTP jet-treated rats. Methods This study utilized Sprague-Dawley (SD) rats as experimental subjects, and wounds measuring 2 cm × 2 cm were produced on the animals' backs. The experimental group was treated with NTP for 5 min/d for 4 weeks. The NTP was injected in a diffused manner into the cage housing the rats. The SD rats that had not received plasma treatment were designated as the control group. Blood was drawn on Postoperative Day 2, Day 4, and at 3 months. An immunohistochemical stain of E-cadherin and 4-hydroxy-2-nonenal (4-HNE), a reactive oxygen species marker, were evaluated and quantified for analysis using a CMYK color model. Results A total of 35 SD rats were included in the study (25 in the NTP group and 10 in the control group). Low dose plasma treatment shortened the wound-healing time without damaging organs. In the NTP group, the white blood cell counts at Day 2 post-NTP treatment was not increased significantly more than that in the control group. After quantification of immunohistochemical staining, 4-HNE was increased at Day 14 compared with Day 7 (16.16 ± 12.81% vs. 55.11 ± 8.11%, p < 0.001), and E-cadherin was also increased (52.17 ± 14.96% vs. 70.46 ± 12.78%, p = 0.04) in the NTP group. After comparison of NTP and the control, it was observed that 4-HNE and E-cadherin were increased in the NTP group on Day 14. Conclusion Short-term, low-dose NTP wound treatment was demonstrated to accelerate wound healing in SD rats without vital organ toxicity. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effects of nonthermal plasma (NTP) induced by helium (He) alone or He plus oxygen (O2) on the generation of reactive oxygen species (ROS) and cell death in anaplastic thyroid cancer cells. Materials and Methods: NTP was generated in He alone or He plus O2 blowing through a nozzle by applying a high alternating current voltage to the discharge electrodes. Optical emission spectroscopy was used to identify various excited plasma species. The apoptotic effect of NTP on the anaplastic thyroid cancer cell lines, such as HTH83, U-HTH 7, and SW1763, was verified with annexin V/propidium staining and TUNEL assay. ROS formation after NTP treatment was identified with fluorescence-activated cell sorting with DCFDA staining. The mitogen-activated protein kinase pathways and caspase cascade were investigated to evaluate the molecular mechanism involved and cellular targets of plasma. Results: NTP induced significant apoptosis in all three cancer cell lines. The plasma using He and O2 generated more O2-related species, and increased apoptosis and intracellular ROS formation compared with the plasma using He alone. NTP treatment of SW1763 increased the expression of phosphor-JNK, phosphor-p38, and caspase-3, but not phosphor-ERK. Apoptosis of SW1763 as well as expressions of elevated phosphor-JNK, phosphor-p38, and caspase-3 induced by NTP were effectively inhibited by intracellular ROS scavengers. Conclusion: NTP using He plus O2 induced significant apoptosis in anaplastic cancer cell lines through intracellular ROS formation. This may represent a new promising treatment modality for this highly lethal disease. [ABSTRACT FROM AUTHOR]

Cooking fumes (CFs) pose a considerable threat to the atmospheric environment and health, thus requiring appropriate mitigation measures. In this study, a nonthermal plasma (NTP) method based on a glass-bead-packed-bed dielectric barrier discharge (DBD) reactor was used to remove CFs. The results revealed that the introduction of glass beads into the DBD reactor considerably enhanced the electrical field, resulting in the marked improvement of the removal of CFs. At a discharge power of 7.4 W, the removal efficiencies of CFs, nonmethane hydrocarbons, and particulate matter with an aerodynamic diameter of ≤ 10 µm (PM 10) reached 89.5%, 98%, and 79%, respectively. Moreover, a high CO x yield of 25.3% and an energy yield of CO x of 41.19 g·kWh−1 were achieved due to the oxidation of carbon-containing compounds. The use of air as the carrier gas resulted in the more efficient removal of CFs compared with the use of nitrogen because of the oxidation effect of active oxygen-containing species derived from the dissociation of oxygen molecules. The performance of the glass-bead-packed-bed DBD reactor was positively correlated with discharge power. Furthermore, on the basis of the identification of byproducts, a reaction pathway underlying the NTP removal of CFs was proposed. The main carbon-containing compounds identified in CFs were esters, hydrocarbons, aldehydes, ketones, and S/Cl-containing compounds, which underwent destruction through a series of dissociation and oxidation reactions, forming CO 2 and H 2 O in the plasma region. This study provides evidence for the use of NTP as an innovative technology for the highly efficient removal of CFs. [Display omitted] • High removal of cooking fumes was achieved using a glass-bead-packed DBD reactor. • Influences of key parameters on the removal of cooking fumes were estimated. • The reaction pathway of plasma removal of cooking fumes was proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nonthermal plasma, temperature swing adsorption, and NOx recirculation are combined. [•] NOx treatment efficiency is greatly improved by the conversion of NO to NO2 prior to adsorption with the small increase in adsorbent as compared to the original system. [•] NOx treatment with extremely high energy efficiency is carried out. [Copyright &y& Elsevier]

The need of clean water and the water-poor are increasing daily in the world. In addition, we are facing a dramatic increase in the industrial pollutions of rivers and groundwater, which led us to find a new way to treat industrial pollutants. The plasma discharge technique is one of the important, safe, and applicable for industrial wastewater decontamination. Decolorization of Brilliant Blue R (BBR) dye as a hazard material was noticed when the contaminated solution was exposed to the plasma discharge technique. The combination between the nonthermal plasma and catalysts was evaluated in this work to optimize the degradation efficiency. The PVDF/(MWCNTs/TiO 2) as three system composites was employed to enhance the nonthermal plasma performance. The surface area, phase purity, shape, and photonic efficiency were characterized employing XRD, FTIR, SEM, DSC, and UV–Vis. techniques. The obtained results of degradation using NTP technique in presence of the PVDF/MWCNTs catalyst have been enhanced the BBR dye degradation by 19% than only plasma treatment for 20 min. The durability processes of prepared PVDF/(MWCNTs/TiO 2) was investigated and evaluated until 8 solar photocatalytic process repeating times. [Display omitted] • Photocatalytic activity of PVDF/(MWCNTs/TiO 2) nanocomposite membbrane was investigated and evaluated. • Photocatalytic process for Brilliant blue R dye was investigated and evaluated by using nonthermal plasma techuiqe. • Using NTP technique for 20 min enhanced the photodegradation rate of BBR dye by 19% than plasma treatment. • The durability processes of prepared membrane for 8 times is evaluated. [ABSTRACT FROM AUTHOR]

Background: Bacterial contamination of surfaces with methicillin-resistant Staphylococcus aureus (MRSA) is a serious problem in the hospital environment and is responsible for significant nosocomial infections. The pathogenic contaminants form biofilms, which are difficult to treat with routine biocides. Thus, a continuous search for novel disinfection methods is essential for effective infection control measures. This demonstration of a novel technique for the control of virulent pathogens in planktonic form as well as in established biofilms may provide a progressive alternative to standard methodology. Methods: We evaluated a novel technique of normal atmospheric nonthermal plasma known as floating-electrode dielectric-barrier discharge (FE-DBD) plasma against a control of planktonic and biofilm forms of Escherichia coli, S aureus, multidrug-resistant methicillin-resistant S aureus (MRSA) -95 (clinical isolate), -USA300, and -USA400, using widely accepted techniques such as colony count assay, LIVE/DEAD BacLight Bacterial Viability assay, and XTT (2,3-Bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay. Results: Exposure of free living planktonic forms of E coli, S aureus, and MRSA were rapidly inactivated by DBD plasma. Approximately 107 bacterial cells were completely (100%) killed, whereas 108 and 109 were reduced by approximately 90% to 95% and 40% to 45%, respectively, in less than 60 seconds (7.8 J/cm2) and completely disinfected in ≤120 seconds. In established biofilms, the susceptibility of MRSA USA400 was comparable with USA300 but less susceptible than MRSA95 (clinical isolate), S aureus, and E coli (P < .05) to FE-DBD plasma, and plasma was able to kill MRSA more than 60% within 15 seconds (1.95 J/cm2). The killing responses were plasma exposure-time dependent, and cell density dependent. The plasma was able disinfect surfaces in a less than 120 seconds. Conclusion: Application of DBD plasma can be a valuable decontamination technique for the removal of planktonic and biofilm-embedded bacteria such as MRSA -USA 300, -USA 400, methicillin-sensitive S aureus (MSSA), and E coli, the more common hospital contaminants. Of interest, E coli was more resistant than S aureus phenotypes. [Copyright &y& Elsevier]

In 2 S 3 -decorated MoO 3 @MoS 2 (In/MoO 3 @MoS 2) composites were fabricated via the in-situ sulfurization of nonthermal plasma for the visible light driven photoreduction of CO 2 to CH 4 and CO. In 2 S 3 can efficiently enhance the photocatalytic activity of In/MoO 3 @MoS 2 in comparison to h-MoO 3. The optimal 3-In/MoO 3 @MoS 2 with a In content of 1.33% and the MoS 2 thickness of around 10 nm presents the superior conversion efficiency of CO 2 , of which the yield of CH 4 and CO are 29.4 and 35.6 μmol g−1 h−1, respectively. However, the long-term photo-corrosion induced to the declining yield of CH 4 and CO after three cycle times. The introduction of In 2 S 3 into MoO 3 @MoS 2 as well as the nonthermal plasma induced S-rich sites and O vacancies is likely to provide the sufficient active sites for promoting CO 2 activation and the efficient junction interface for achieving the transfer and separation of charge carriers. [Display omitted] • In 2 S 3 /MoO 3 @MoS 2 was prepared via in-situ nonthermal plasma route. • In 2 S 3 /MoO 3 @MoS 2 presents the excellent photoreduction activity toward CO 2. • CO 2 is efficiently converted into CH 4 and CO in visible light region. • S-rich sites and O vacancies play the vital role in CO 2 photoreduction. [ABSTRACT FROM AUTHOR]

To enhance the solar-light photocatalytic efficiency of MoO 3 for conversion of CO 2 into CH 4 and CO, CuS and MoS 2 co-modified h-MoO 3 (MoO 3 @MoS 2 -CuS) composites were sulfurized by dielectric barrier discharge (DBD) plasma. The photocatalytic activities of MoO 3 @MoS 2 and MoO 3 @MoS 2 -CuS for solar-light driven CO 2 photoreduction were better than that of h-MoO 3 , while MoO 3 @MoS 2 -CuS presented the enhancing CH 4 yield and the declining CO yield. It's ascribed to the improved visible light response and the efficient charge transfer and separation. In addition, CO 2 and H 2 O molecules were trapped and photo-reduced at the naked edge-rich sites of junction interface between MoO 3 , MoS 2 , and CuS. The optimal MoO 3 @MoS 2 -CuS-3 with the CuS content of 2.27 wt% presented the CH 4 yield of 44.64 μmol g−1 h−1 and CO yield of 7.59 μmol g−1 h−1, and its durability was slightly declined after three cycles. [Display omitted] • MoO 3 @MoS 2 -CuS was in-situ sulfurized in the nonthermal plasma. • MoO 3 @MoS 2 -CuS enhanced the visible-light harvesting and charge transfer. • MoO 3 @MoS 2 -CuS presented the excellent CH 4 yield and inferior CO yield. [ABSTRACT FROM AUTHOR]