scholarly journals Cold Atmospheric Plasma in Dentistry

2016 ◽  
Vol 1 (2) ◽  
pp. 82-86
Author(s):  
Rajesh S Nair ◽  
Betty Babu ◽  
Eeshan Mushtaq
Keyword(s):  
Atmospheric Plasma ◽  
Natural Phenomenon ◽  
Light Sources ◽  
Bacterial Inactivation ◽  
Fusion Reactions ◽  
Heavy Particles ◽  
Cold Atmospheric Plasma ◽  
Aurora Borealis ◽  
Nuclear Fusion Reactions ◽  
Tissue Alteration

ABSTRACT Introduction Plasma is the fourth state of matter and others are liquid, gas, and solid. Plasma occurs as a natural phenomenon in the universe and appears in the form of fire, in the polar aurora borealis and in the nuclear fusion reactions of the sun. It can be produced artificially which has gained importance in the fields of plasma screens or light sources. Plasma is of two types: Thermal and nonthermal or cold atmospheric plasma (CAP). Thermal plasma has electrons and heavy particles (ions and neutral) at the same temperature. Cold atmospheric plasma is said to be nonthermal as it has electron at a hotter temperature than the heavy particles that are at room temperature. Cold atmospheric plasma is a specific type of plasma, i.e., <104°F at the point of application. It could become a new and painless method to prepare cavities for restoration with improved longevity. Also it is capable of bacterial inactivation and noninflammatory tissue alteration, which makes it an attractive tool for the treatment of dental caries and for composite restorations. Plasma can also be used for tooth whitening. This review focuses on some dental application of plasma. How to cite this article Nair RS, Babu B, Mushtaq E. Cold Atmospheric Plasma in Dentistry. J Oper Dent Endod 2016;1(2):82-86.

Cold Atmospheric Plasma Decontamination of the Pericarps of Fruit

2008 ◽  
Vol 71 (2) ◽  
pp. 302-308 ◽  
Author(s):  
STEFANO PERNI ◽  
DAVID W. LIU ◽  
GILBERT SHAMA ◽  
MICHAEL G. KONG
Keyword(s):  
Detection Limit ◽  
Operating Conditions ◽  
Atmospheric Plasma ◽  
Resistant Organism ◽  
Efficient Production ◽  
Operating Voltage ◽  
Bacterial Inactivation ◽  
Cold Atmospheric Plasma ◽  
Cell Counts ◽  
Oxygen Atoms

This investigation describes the inactivation by cold atmospheric plasmas of one pathogenic and three spoilage organisms on the pericarps of mangoes and melons. The operating voltage necessary for efficient microbial decontamination of fruit pericarps was first established using Escherichia coli at a concentration of 107 CFU/cm2 on the surface of mango. It was found that, when the plasma was sustained slightly above its breakdown voltage of 12 kV (peak to peak), no inactivation was detected when cells were plated onto tryptone soya extract agar (TSA). However, when plated onto eosin methylene blue agar, sublethal injury corresponding to approximately 1 log reduction was achieved, whereas on TSA supplemented with 4% NaCl a greater reduction of 1.5 log was revealed. When the voltage was increased by 33% to 16 kV, a reduction in cell counts of 3 log was achieved on all three plating media. Further investigations at these new operating conditions were conducted using a range of spoilage microorganisms (Saccharomyces cerevisae, Pantoea agglomerans, and Gluconacetobacter liquefaciens) all at a surface concentration of 106 CFU/cm2 on the pericarps of mango and melon. P. agglomerans and G. liquefaciens were reduced below the detection limit (corresponding to 3 log) after only 2.5 s on both fruits, whereas E. coli required 5 s to reach the same level of inactivation. S. cerevisae was the most resistant organism studied and was reduced in numbers below the detection limit after 10 s on mango and 30 s on melon. The optical emission spectra generated by the cold atmospheric plasma at both high and low operating voltages were compared in order to identify putative lethal species. It was shown that an increase in the applied voltage led to more efficient production of reactive plasma species, particularly oxygen atoms, and the production of oxygen atoms was related to the level of bacterial inactivation achieved. Production of atomic oxygen could be used as an indicator of inactivation efficiency for scaling up cold plasma systems for whole fruit.

Formation of ammonium in saline solution treated by nanosecond pulsed cold atmospheric microplasma: a route to fast inactivation of E. coli bacteria

RSC Advances ◽  
2015 ◽  
Vol 5 (52) ◽  
pp. 42135-42140 ◽  
Author(s):  
Simon Maheux ◽  
David Duday ◽  
Thierry Belmonte ◽  
Christian Penny ◽  
Henry-Michel Cauchie ◽  
...  
Keyword(s):  
Saline Solution ◽  
Atmospheric Plasma ◽  
Main Process ◽  
Bacterial Inactivation ◽  
Fast Inactivation ◽  
Cold Atmospheric Plasma ◽  
E Coli ◽  
Solution Treated ◽  
Saline Solutions ◽  
First Time

The formation of significant NH4+species in saline solutions treated by He/N2cold atmospheric plasma is proposed for the first time as the main process responsible for the fast bacterial inactivation ofE. coliat ambient temperature and physiological pH.

scholarly journals Combined Antimicrobial Effect of Bio-Waste Olive Leaf Extract and Remote Cold Atmospheric Plasma Effluent

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1890
Author(s):  
Jose Gustavo De la Ossa ◽  
Hani El Kadri ◽  
Jorge Gutierrez-Merino ◽  
Thomas Wantock ◽  
Thomas Harle ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Leaf Extract ◽  
Preliminary Investigation ◽  
Atmospheric Plasma ◽  
Aureus Strain ◽  
Bacterial Inactivation ◽  
Olive Leaf ◽  
Cold Atmospheric Plasma ◽  
E Coli ◽  
Olive Leaf Extract

A novel strategy involving Olive Leaf Extract (OLE) and Cold Atmospheric Plasma (CAP) was developed as a green antimicrobial treatment. Specifically, we reported a preliminary investigation on the combined use of OLE + CAP against three pathogens, chosen to represent medical and food industries (i.e., E. coli, S. aureus and L. innocua). The results indicated that a concentration of 100 mg/mL (total polyphenols) in OLE can exert an antimicrobial activity, but still insufficient for a total bacterial inactivation. By using plain OLE, we significantly reduced the growth of Gram positive S. aureus and L. innocua, but not Gram-negative E. coli. Instead, we demonstrated a remarkable decontamination effect of OLE + CAP in E. coli, S. aureus and L. innocua samples after 6 h. This effect was optimally maintained up to 24 h in S. aureus strain. E. coli and L. innocua grew again in 24 h. In the latter strain, OLE alone was most effective to significantly reduce bacterial growth. By further adjusting the parameters of OLE + CAP technology, e.g., OLE amount and CAP exposure, it could be possible to prolong the initial powerful decontamination over a longer time. Since OLE derives from a bio-waste and CAP is a non-thermal technology based on ionized air, we propose OLE + CAP as a potential green platform for bacterial decontamination. As a combination, OLE and CAP can lead to better antimicrobial activity than individually and may replace or complement conventional thermal procedures in food and biomedical industries.

Status of muon catalysis of nuclear fusion reactions

1990 ◽  
Vol 160 (8) ◽  
pp. 47-103 ◽  
Author(s):  
Leonid I. Men'shikov ◽  
L.N. Somov
Keyword(s):  
Nuclear Fusion ◽  
Fusion Reactions ◽  
Nuclear Fusion Reactions ◽  
Muon Catalysis

Targeting Protective Catalase of Tumor Cells with Cold Atmospheric Plasma- Activated Medium (PAM)

2018 ◽  
Vol 18 (6) ◽  
pp. 784-804 ◽  
Author(s):  
Georg Bauer
Keyword(s):  
Control System ◽  
Singlet Oxygen ◽  
Tumor Cells ◽  
Plasma Potential ◽  
Atmospheric Plasma ◽  
Antitumor Action ◽  
Active Principle ◽  
Reaction Products ◽  
Cold Atmospheric Plasma

Background: Application of cold atmospheric plasma to medium generates “plasma-activated medium” that induces apoptosis selectively in tumor cells and that has an antitumor effect in vivo. The underlying mechanisms are not well understood. Objective: Elucidation of potential chemical interactions within plasma-activated medium and of reactions of medium components with specific target structures of tumor cells should allow to define the active principle in plasma activated medium. Methods: Established knowledge of intercellular apoptosis-inducing reactive oxygen/nitrogen species-dependent signaling and its control by membrane-associated catalase and SOD was reviewed. Model experiments using extracellular singlet oxygen were analyzed with respect to catalase inactivation and their relevance for the antitumor action of cold atmospheric plasma. Potential interactions of this tumor cell-specific control system with components of plasma-activated medium or its reaction products were discussed within the scope of the reviewed signaling principles. Results: None of the long-lived species found in plasma-activated medium, such as nitrite and H2O2, nor OCl- or .NO seemed to have the potential to interfere with catalase-dependent control of apoptosis-inducing signaling of tumor cells when acting alone. However, the combination of H2O2 and nitrite might generate peroxynitrite. The protonation of peroxnitrite to peroxynitrous acid allows for the generation of hydroxyl radicals that react with H2O2, leading to the formation of hydroperoxide radicals. These allow for singlet oxygen generation and inactivation of membrane-associated catalase through an autoamplificatory mechanism, followed by intercellular apoptosis-inducing signaling. Conclusion: Nitrite and H2O2 in plasma-activated medium establish singlet oxygen-dependent interference selectively with the control system of tumor cells.

The Application of the Cold Atmospheric Plasma-Activated Solutions in Cancer Treatment

2018 ◽  
Vol 18 (6) ◽  
pp. 769-775 ◽  
Author(s):  
Dayun Yan ◽  
Jonathan H. Sherman ◽  
Michael Keidar
Keyword(s):  
Cancer Treatment ◽  
Atmospheric Plasma ◽  
Current Status ◽  
Cold Atmospheric Plasma ◽  
Anti Cancer ◽  
Long Time ◽  
Key Topics ◽  
The Common

Background: Over the past five years, the cold atmospheric plasma-activated solutions (PAS) have shown their promissing application in cancer treatment. Similar as the common direct cold plasma treatment, PAS shows a selective anti-cancer capacity in vitro and in vivo. However, different from the direct cold atmospheric plasma (CAP) treatment, PAS can be stored for a long time and can be used without dependence on a CAP device. The research on PAS is gradually becoming a hot topic in plasma medicine. Objectives: In this review, we gave a concise but comprehensive summary on key topics about PAS including the development, current status, as well as the main conclusions about the anti-cancer mechanism achieved in past years. The approaches to make strong and stable PAS are also summarized.

Proposed Solutions to Achieve Nuclear Fusion

Engevista ◽  
2017 ◽  
Vol 19 (5) ◽  
pp. 1496
Author(s):  
Relly Victoria Virgil Petrescu ◽  
Raffaella Aversa ◽  
Antonio Apicella ◽  
Florian Ion Petrescu
Keyword(s):  
Nuclear Reactor ◽  
Nuclear Reactions ◽  
Nuclear Fusion ◽  
Nuclear Fission ◽  
Light Nuclei ◽  
Fast Neutrons ◽  
Fusion Reactions ◽  
Nuclear Fusion Reactions ◽  
The Masses ◽  
Fusion Products

Despite research carried out around the world since the 1950s, no industrial application of fusion to energy production has yet succeeded, apart from nuclear weapons with the H-bomb, since this application does not aims at containing and controlling the reaction produced. There are, however, some other less mediated uses, such as neutron generators. The fusion of light nuclei releases enormous amounts of energy from the attraction between the nucleons due to the strong interaction (nuclear binding energy). Fusion it is with nuclear fission one of the two main types of nuclear reactions applied. The mass of the new atom obtained by the fusion is less than the sum of the masses of the two light atoms. In the process of fusion, part of the mass is transformed into energy in its simplest form: heat. This loss is explained by the Einstein known formula E=mc2. Unlike nuclear fission, the fusion products themselves (mainly helium 4) are not radioactive, but when the reaction is used to emit fast neutrons, they can transform the nuclei that capture them into isotopes that some of them can be radioactive. In order to be able to start and to be maintained with the success the nuclear fusion reactions, it is first necessary to know all this reactions very well. This means that it is necessary to know both the main reactions that may take place in a nuclear reactor and their sense and effects. The main aim is to choose and coupling the most convenient reactions, forcing by technical means for their production in the reactor. Taking into account that there are a multitude of possible variants, it is necessary to consider in advance the solutions that we consider them optimal. The paper takes into account both variants of nuclear fusion, and cold and hot. For each variant will be mentioned the minimum necessary specifications.

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