Macronutrients
Chuong Pham-Huy, Bruno Pham Huy in Food and Lifestyle in Health and Disease, 2022
Waxes are esters of long-chain alcohols and long-chain fatty acids and belong to simple lipid group such as sterols and triglycerides. Waxes are long-chain apolar lipidic compounds and often found on the surface of plants and animals (68, 118). Waxes exist in solid or semi-solid form (ointment form) and have melting points from 40° C (104° F) to 120° C (248° F). They are water insoluble, but soluble in organic, nonpolar solvents (118). Waxes are produced by many plants and animals. Beeswax, spermaceti, wool grease, and lanolin are important animal waxes, and used mostly in pharmaceutical and food industries. The vegetable waxes include carnauba wax, candelilla, and sugar cane waxes containing policosanol. The mineral waxes include petroleum waxes, ozokerite, and montan (118).
The late Middle Ages
Michael J. O’Dowd in The History of Medications for Women, 2020
According to Dorland’s medical dictionary (1932), wax is any one of a series of plastic substances deposited by insects or obtained from plants. They are esters of various fatty acids with higher (usually monohydric) alcohols. The wax used in pharmacy is principally beeswax, the material which honeycomb is made from. It consists chiefly of ceran and myricin. Chinese wax is a hard white wax of insect origin procured from Fraxinus chinensis, a Chinese ash tree while Japanese wax comes from the fruit of bayberry (Myrica cerifera) and other species of the same genus. Beeswax is obtained by melting the walls of the honeycomb of the bee (Apis mellfera) with hot water and removing the foreign matter. Cerason or mineral wax is obtained by purifying ozokerite, a naturally-occurring solid paraffin. It is used as a substitute for beeswax or hard paraffin. Cera alba or white beeswax is a somewhat translucent solid obtained by air-bleaching wax and ‘being of moderate temperament, forms the basis of many other medicines’ (Adams, 1847 p. 169). Wax was contained in ointments, pills, plasters and suppositories.
Beam Delivery Using Passive Scattering *
Harald Paganetti in Proton Therapy Physics, 2018
Ideally, the range compensator provides pullback with as little scattering as possible. Scattering decreases the compensator’s conforming ability and generates undesirable cold and hot spots inside the target. Low-Z, high-density materials give the least scattering per energy loss. Lucite and wax are the two materials most commonly used. Proponents of wax favor it because it is easier (faster) to mill, has lower cost, and can be recycled. Lucite users value its transparency, which allows for visual screening for air pockets and validation of the isoheight lines by placing it on a paper printout during quality assurance. A standard milling machine mills the desired profile into a blank compensator. Resolution needs to be weighed against speed when selecting drill bit size and spacing. The smallest drill provides the best lateral resolution in conforming the dose, but it takes the longest time to drill. Because of scattering, there is a lower limit below which reduction of the drill bit size does not significantly improve conformity anymore. A typical drilling pattern will use a 5-mm diameter drill bit and a spacing of 5 mm. For such a pattern, machining times (for Lucite) range from 10 min for a small brain lesion, 45 min for a prostate, and up to 4 h for a 2 l sarcoma field.
Microencapsulation of retinyl palmitate by melt dispersion for cosmetic application
Published in Journal of Microencapsulation, 2020
Aditi Nandy, Eliza Lee, Abhyuday Mandal, Raha Saremi, Suraj Sharma
In this study, we investigated a novel approach of melt dispersion to microencapsulate RP with a view to making the cosmetic formulation sustainable as well as cost-effective. Melt dispersion is an inexpensive and convenient method that can produce free-flowing particles with mean size range of 50–150 µm (Djordjević et al.2015). This size range is suitable for cosmetic applications. Melt dispersion method has not been explored before to microencapsulate retinoids, possibly because the process involves heating and melting of encapsulation materials. However, waxes have been previously used to encapsulate bioactive compound, including heat-sensitive ones (Bodmeier et al.1992). Natural waxes such as beeswax can provide anti-inflammatory, skin softening and skin healing properties, whereas carnauba wax helps provide protective skin barrier. Using natural ingredients in cosmetic formulation can provide skin benefits, without incorporating auxiliary solvents or chemicals that can have adverse side effects on sensitive skin. Other encapsulation methods such as coacervation, ionic gelation or inclusion complexation often require the use of stabilizers/crosslinking agents or expensive methods of preparation. From this perspective, in order to encapsulate active ingredient such as retinoids, melt dispersion can be an economical and eco-friendly method to impart skin- benefits of retinyl palmitate as well as natural waxes, with minimum use of synthetic chemicals.
Control of biofouling on pearl oysters Pinctada imbricata using wax and Chinese herbs
Published in Biofouling, 2019
Lingtong Ye, Lin Wu, Zhaorui Wang, Jingzhe Jiang, Jiangyong Wang
Spraying with wax represents an inexpensive and practical solution to AF of commercial pearl oyster cultures. However, prior to commercial application, research on what additives might improve wax adhesiveness (to prevent it from flaking off shells so easily), its optimal coating thickness, and spraying temperature and time to minimize wax loss from shells, would be beneficial. Not only did the byssus threads produced by pearl oysters after treatment (that linked shells together) decrease the impact of water flux on wax layers and facilitate wax retention, but the high coating temperature might even have encouraged byssus production (Van Winkle 1970; De Nys and Ison 2004). Post-treatment wax retention might be improved if pearl oysters were temporarily suspended in slow-flowing waters after coating to facilitate byssus production, before being relocated for longer-term suspension in farming regions.
Chronic inflammatory reaction to bone wax in cochlear implantation: A case report and literature review
Published in Cochlear Implants International, 2020
Kylen Van Osch, Peng You, Kim Zimmerman, John Yoo, Sumit K. Agrawal
Bone wax is an excellent hemostatic agent and is commonly used during bony surgeries. Present-day bone wax is composed of beeswax, paraffin, and isopropyl palmitate (Hill et al., 2013). While bone wax is largely considered to be safe, it can cause adverse effects months to years after surgery. Bone wax has been reported to cause inflammatory reactions in the areas of neurosurgery (Ateş et al., 2004; Spennato et al., 2016), cardiac surgery (Vestergaard et al., 2014), orthopedic surgery (Allen-Wilson et al., 2015; Hill et al., 2013), ophthalmic surgery (Katz and Rootman, 1996; Wolvius and van der Wal, 2003), and oral & maxillofacial surgery (Katre et al., 2010).
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