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Environmental Inhaled Agents and Their Relation to Lung Cancer
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
Carbon-containing products that originate from coal or petroleum include coal gas, coke, gasoline, kerosene, and tar. The risk of developing lung cancer has been clearly demonstrated in British gas house workers (Doll et al, 1972) and U.S. coke oven workers in the carbonization of steel (Redmond et al, 1972), all of whom were exposed to coal carbonization volatiles; the risk factor is approximately two- to threefold (Shy and Struba, 1982). The risk for roofers, oil refinery workers, and carbon black (over 99% carbon with traces of polycyclic aromatic hydrocarbons) workers is less certain (Hodgson and Jones, 1985; Parkes, 1982a).
Vegetables
Published in Christopher Cumo, Ancestral Diets and Nutrition, 2020
The foregoing does not exclude plants from the archeological record. Several factors affect persistence. First, by desiccating plants, aridity increases chances of preservation. Southwestern Asia, Egypt, and North Africa supply such an environment, which may explain the antiquity of evidence for the regions’ early invention or adoption of agriculture. Second, not all plant parts are equally susceptible to decay. For example, microbes cannot break down silica (silicon dioxide or SiO2), which is common in plants wherever soils contain it. Plant structures with silica—like grain kernels’ tough outer coat (the husk, hull, or chaff)—are known as phytoliths and may constitute the sole evidence for plant consumption in remote times. Third, cooking without enough oxygen prevents complete combustion. The remaining carbon persists through a process known as carbonization. Fourth, freezing temperatures retard decomposition. Fifth, waterlogging prevents aerobic but not anaerobic degradation. Sixth, where present, calcium (Ca2+) cations and phosphate (PO43-) anions may replace plant cells, a process known as mineralization. Calcium phosphate compounds endure longer than plants’ organic molecules.
Principles of the Laser and Applications
Published in Sujoy K. Guba, Bioengineering in Reproductive Medicine, 2020
Some quantitative aspects of energy are important in surgery. A beam power level of 40 W with a spot diameter of 0.5 mm gives an energy density of about 20 kW/cm2. In use the spot is moved over the tissue and the actual biological effect then depends on the beam movement rate. For incision of skin, fat, or fascia, power densities range from 60 to 200 kW/cm2. These high power densities are achieved by having a small spot diameter such as 125 μ. To remove adhesions a power density of 0.8 to 4 kW/cm2 is adequate. Interestingly after operating on a serosal surface “relasing” with a power density of 300 to 600 W/cm2 reduces the formation of postoperative adhesions. When using for coagulation the power density required is not more than 150 W/cm2. If tissue carbonization occurs heat transfer to the underlying tissue is markedly reduced. At times it is necessary to wipe off the carbon film with a wet sponge. The film of water then left behind attenuates the beam and therefore it is desirable to wipe off the moisture film with a dry sponge.
Crafting two-dimensional materials for contrast agents, drug, and heat delivery applications through green technologies
Published in Journal of Drug Targeting, 2023
Dwi Setyawan, Tahta Amrillah, Che Azurahanim Che Abdullah, Fasih Bintang Ilhami, Diva Meisya Maulina Dewi, Zuhra Mumtazah, Agustina Oktafiani, Fayza Putri Adila, Moch Falah Hani Putra
Coconut is one of many kinds of tropical plants that can be used as a source in graphene synthesis. Due to their abundance in nature, high hardness, exhibit high volatility, low ash content, and consisting of C-amorphous constituents, coconut plants could shed a light on the green synthesis of eco-friendly carbon-based compounds [53]. Graphene could be produced by converting coconut shells into charcoal or activated carbon through the carbonisation process [63]. Coconut shell charcoal contains 74.3% carbon and thus can be used for graphite powder as the primary precursor for rGO synthesis [53]. It was also shown that the rGO synthesised by coconut shells as raw materials has the same density as commercial rGO. It was also found that the rGO-based coconut shell exhibit semiconducting properties [64]. The production of carbon material is primarily comprised of two steps: I the raw materials are pre-carbonised in an inert atmosphere to produce carbonaceous materials, and (ii) the carbonised carbon is finalised by the carbonisation process and chemical activation with chemical agents [54]. Graphene could be produced by converting coconut shells into charcoal or activated carbon through the carbonisation process [64,65].
Factors related to the absorption rate of benign thyroid nodules after image-guided microwave ablation: a 3-year follow-up
Published in International Journal of Hyperthermia, 2022
Li-Hong Liu, Bei-Bei Yang, Ying Liu, Jin-Ling Wang, Dan-Dan Wang, Hong-Yu Ding, Shu-Rong Wang
Our study identified energy delivered per ml as a factor related to nodule VRR. The underlying mechanism for this relationship might arise from the process of MWA. If the unit volume energy is too much, the central temperature of the tissue will be too high, often exceeding 150 °C [43,44], which will carbonize the ablated tissue. It is difficult for the body to absorb this carbonization. The fixed electrode technique or high output power was applied to block blood flow in the most richly vascular portions of the nodule. After ablation, we found that the absorption of some nodules with blocked peripheral blood flow was slow. We speculated that blockage of peripheral blood flow was a factor affecting nodule absorption. After ablation, the ablation area enters a period of damage repair, and the necrotic tissue in the ablation area is constantly engulfed and removed by macrophages and other inflammatory response cells [45]. Blocking blood flow around the ablation nodules may break the absorptive balance of necrotic tissue.
Treatment of Thoracic Ossification of Posterior Longitudinal Ligament with One-Stage 360 Degree Circumferential Decompression Assisted by Piezosurgery
Published in Journal of Investigative Surgery, 2022
Peng Yang, Rile Ge, Zhong-qiang Chen, Bing-tao Wen
It should be noted that limitations of piezosurgery technique also existed. Hu et al. [14] used piezosurgery to perform spinal osteotomy in 128 patients with spinal diseases, of which two patients had cerebrospinal fluid leakage directly related to piezosurgery, indicative of its risk despite not causing significant nerve injury. All piezosurgery cutting planes are carbonized to varying degrees which allows for continuous cooling of flowing water in bone cutting (Figure 5). However, a large amount of heat is still produced despite carbonization. Despite its reported thermogenic effect, there was no direct damage to the nerve structure of the patients in the study because the surgeons repositioned the ultrasonic tool head from time to time to reduce thermal damage. Therefore, piezosurgery did not increase the risk of nerve structure in this study. There were also no abnormal signals in neuroelectrophysiological monitoring. Moreover, the occurrence of postoperative intercostal neuralgia also noted in the current study (13.9%), which was consistent with previous literature reports [10].