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A depiction of factors affecting HIV transmission through sharing syringes and the role of BTH/PH in the probability of transmission. BTH/PH factors are overlaid with the oval.

A depiction of factors affecting HIV transmission through sharing syringes and the role of BTH/PH in the probability of transmission. BTH/PH factors are overlaid with the oval.

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Background and aims Using mathematical modeling to illustrate and predict how different heroin source-forms: “black tar” (BTH) and powder heroin (PH) can affect HIV transmission in the context of contrasting injecting practices. By quantifying HIV risk by these two heroin source-types we show how each affects the incidence and prevalence of HIV ove...

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... building a model we used the following mechanistic logic (Fig 2). A person can become HIV infected when a number of HIV viruses enters his or her bloodstream. ...

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... 3,7,14,[17][18][19][20][21] Researchers are embracing simulation models to generate insights about a range of substancerelated topics (e.g., substance use laws and regulations, social networks, economics). 16,[22][23][24][25][26][27][28] However, these models are often highly complex and use many idiosyncratic parameters and assumptions to examine specific circumstances. Consequently, the growing subfield of substance use simulation will have difficulty collaborating and building cumulative progress. ...
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