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Emerging Diseases
Published in Gary S. Moore, Kathleen A. Bell, Living with the Earth, 2018
Gary S. Moore, Kathleen A. Bell
Disease: Persons who swallow Cryptosporidium cysts may develop symptoms within 2–10 days. The oocysts reach the upper small bowel where they excyst and produce four infectious sporozoites that attach to the surface epithelium of the digestive tract and reproduce, forming more oocysts and sporozoites. Many of the organisms are excreted while others maintain the infection. The symptoms include watery diarrhea, stomach cramps, nausea, and a slight fever. These symptoms are self-limiting and will normally last for 2 weeks or less. The organism may be shed from the intestines for up to 2 months after the initial illness and so spread this disease to others through fecal-oral transmission. Persons who have a weakened immune system such as those with HIV/AIDS, cancer and transplant patients, or those on immuno-suppressive drugs, are at increased risk from infection, and may develop serious and life-threatening illness from this organism. There is no pharmaceutical treatment for Cryptosporidiosis and the more serious illness is managed by fluid replacement.165
Assessment of 3He Release from Uranium Tritide Bed Considering Cyclic Operation Using Empirical Models
Published in Fusion Science and Technology, 2023
Jae-Uk Lee, Dong-you Chung, Hyun-goo Kang, Min Ho Chang, Pil-Kap Jung
Verhulst first modeled this kind of self-limiting growth in the formation of the logistic function for the biological population.[13] It can be found in various applications, such as mathematical modeling for biological, economic, and sociological phenomena today. Instead of complex modeling considering several kinds of qualitative information such as uranium processing or tritium atmosphere, the concept of the logistic function can be an easy and practical solution for reasonable 3He release modeling. Note Eqs. (1) through (6):
Convergence analysis of a patch structure Nicholson’s blowflies system involving an oscillating death rate
Published in Journal of Experimental & Theoretical Artificial Intelligence, 2022
Since the logical self-limiting control can occur at any stage of the population life cycle, it is necessary to introduce mature and feedback delays (also known as incubation delays) corresponding to maturity and feedback lags into the same time-dependent birth function (Berezansky & Braverman, 2009; Xu et al., 2020). Especially, the mature and feedback delays are often different. As a result, not only the following Nicholson’s blowflies system with patch structure and different maturation and feedback delays:
Developing gene drive technologies to eradicate invasive rodents from islands
Published in Journal of Responsible Innovation, 2018
Caroline M. Leitschuh, Dona Kanavy, Gregory A. Backus, Rene X. Valdez, Megan Serr, Elizabeth A. Pitts, David Threadgill, John Godwin
Regarding epistemic uncertainty, much of the biological risk has to do with containment. There is a possibility, however slight, that an engineered rodent could mate with a closely related, non-invasive species and spread the gene drive system (Esvelt et al. 2014). Quantifying this possibility is difficult – even with present-day advanced genetic analysis tools, when and why species hybridize and the ability to hybridize is still not well understood (Harrison and Larson 2014). Engineered rodents on a contained island could also escape to mainland populations and potentially affect more than the intended target, a risk noted by Esvelt et al. (2014), who also propose first using a CRISPR gene drive mechanism to introduce an ‘innocuous’ sequence to help mitigate the risk of unintended spread. This would be a genetically inert sequence that is not found in other organisms, which could be used as a target sequence for inserting the functional gene drive system (Esvelt et al. 2014). Targeting a specifically designed sequence could reduce the biological risk of the gene drive mechanism spreading to other populations of mice or related species of rodents. Especially in cases when an engineered gene is not self-limiting, the potential for global population suppression or extinction could become an issue of both conservation and international concern. To understand how a gene drive would behave in the field and develop proper containment measures, we, along with other researchers, are looking at gene drive systems that have already been implemented in insects, performing behavioral and genetic experiments on rodents in the lab, and using ecological modeling. However, it is impossible to eliminate epistemic uncertainty regarding how the technique would work in the field without field trials in a specific environment.