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Lifestyle Medicine and Cardiovascular Disease
Published in James M. Rippe, Manual of Lifestyle Medicine, 2021
Unfortunately, cigarette smoking in men remains at approximately 18% and in women 14%. Thus, the overall percentage of cigarette smoking for adults over the age of 18 is slightly more than 15% (21). Sadly, the rate of discontinuing cigarette smoking has slowed down in the last decade. The good news is that substantial benefits accrue in terms of reduction of CVD in individuals who stop smoking. These benefits occur over a very brief period of time. It should be noted, however, that secondhand smoke also substantially increases the risk of CVD.
Surface Modification Techniques
Published in S Santhosh Kumar, Somashekhar S. Hiremath, Role of Surface Modification on Bacterial Adhesion of Bio-Implant Materials, 2020
S Santhosh Kumar, Somashekhar S. Hiremath
Chemical vapour deposition (CVD): CVD has been used to deposit diamond nanoparticles on Ti dental implants to provide ultrahigh hardness, enhanced toughness, and good adhesion. CVD differs from PVD in the processes employed; it only uses chemical bonding to deposit the layer while PVD uses physical forces. CVD utilizes a mixed source material while PVD utilizes a pure source material. For CVD, the precursor eventually decomposes and leaves the desired layer of the source material in the substrate. HA is a bioactive ceramic with a crystal structure similar to that of a native bone and teeth minerals (Rasouli et al., 2018; Subramani et al., 2018).
HfO2 Thin Film for Microelectromechanical Systems Application
Published in Iniewski Krzysztof, Integrated Microsystems, 2017
The surface damage inherent in a sputtering PVD process and device morphology inherent to the scaling process generally rule out PVD deposition approaches. Within all the manufacturing options, chemical vapor deposition-based methods, ALD and MOCVD, draw the highest industrial interest for deposition of high-k dielectrics. ALD approaches appear to be promising, because of its precision in layer growth and high layer uniformity in large deposition areas such as 300 mm wafer technology. However, the generation of polycrystalline dielectrics in the manufacturing environment may cause high leakage currents and a possible diffusion path for dopants along its grain boundaries. Another major disadvantage of ALD is the long processing time, which makes it an expensive tool to operate. Besides, the demand for complex precursors decreases its flexibility for using in material research. The other technique is MOCVD, because of its good film conformality and control on deposition rates. However, choice of the precursor, deposition temperature, and incorporation of carbon impurities are major concerns in this technique.
Exploring the functionalization of Ti-6Al-4V alloy with the novel antimicrobial peptide JIChis-2 via plasma polymerization
Published in Biofouling, 2023
Gabriella Teresinha Lima Teixeira, Rogério Valentim Gelamo, Malu Mateus Santos Obata, Leonardo Eurípedes de Andrade Silva, Marcos Vinícius da Silva, Carlo José Freire de Oliveira, Brunela Pereira da Silva, Idalina Vieira Aoki, Jeferson Aparecido Moreto, Natália Bueno Leite Slade
In the biomedical field, plasma deposition methods are often used to impart specific functional groups to materials and can be used to improve animal cell adhesion to surfaces (Kastellorizios et al. 2012). Plasma polymerization is a sustainable coating method and allows the subsequent immobilization of biomolecules in metallic biomaterials. Thus, the Plasma Enhanced Chemical Vapor Deposition (PECVD) technique can be adopted for the formation of thin films on the metallic surface with specific compositions (Sardella et al. 2002). Seo et al. (2010) used plasma polymerization to deposit a thin film of polyacrylic acid (PAA) on titanium to immobilize the RGD peptide. The polymerization process was used to promote the formation of carboxyl groups (COOH) in the biomaterial, to provide the subsequent covalent bond with the amide group (NH2) of the peptide.
Characterization, antibacterial, total antioxidant, scavenging, reducing power and ion chelating activities of green synthesized silver, copper and titanium dioxide nanoparticles using Artemisia haussknechtii leaf extract
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
In order to prepare metallic NPs, several methods have been applied. For example, using a various chemicals as precursors and more amounts of surfactants as stabilizing agents is one of the common methods in NPs synthesis. In this way, there are the different preparation methods in the synthesis of metallic NPs from several materials [4]. Today, the way of NP synthesis with a small size is important part of nanotechnology function [5]. There are several ways for NPs synthesis such as chemical, physical, biological and enzymatic methods. Physical vapour deposition (PVD), atomic layer deposition, spay pyrolysis, ball milling, laser desorption, lithographic methods, layer by layer growth, ultra-thin films and molecular beam epitaxy are some examples of physical methods. Also, chemical methods include chemical vapour deposition (CVD), wet chemical and co-precipitation. In contrast to these two basic methods, biological synthesis ways of NPs have less energy need and are eco-friendly methods [6].
Modeling the antifouling properties of atomic layer deposition surface-modified ceramic nanofiltration membranes
Published in Biofouling, 2022
Welldone Moyo, Nhamo Chaukura, Machawe M. Motsa, Titus A. M. Msagati, Bhekie B. Mamba, Sebastiaan G. J. Heijman, Thabo T. I. Nkambule
Surface modifications such as pore size tuning are important for engineering the selectivity and flux of membranes. Commonly used modification methods include electroless gold deposition and polymer grafting (Sun et al. 2013; Mustafa et al. 2016). However, these methods are laborious, time consuming and involve the use of hazardous chemicals, hence their application is limited (Sun et al. 2013). Vapor deposition techniques such as physical vapor deposition (PVD), chemical vapor deposition (CVD) and atomic layer deposition (ALD) offer better alternatives for surface and pore size modification because they are not specific to the chemistry of the substrate material (Kim and Oh 2014). Moreover, the thickness of the coating can be manipulated over a wide range (Kim and Oh 2014).