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01-16-2002, 03:09 PM | #141 |
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Since we started to speak about probability I will hint to you a rigorous proof why HIV infection is not real threat, if condoms are consistently used. My reasoning will however be based on only simple model, I will use the results of "Interacting Particle Systems", this is a relatively young branch of probability theory, the standard reference is Liggett, T.M. (1985). Interacting Particle Systems, Springer, New York. I do not know about recent developments, these models are often notoriously untreatable, but they are generally able to account better for the reality than the standard use of coupled differential equations of varying complexity with multiple parameters, consider this simplified situation: Each person lives at a point of Z^2, i.e. each individual has four neighbours, with each of them she or he has regular sexual intercourses at average pace, say 3 times a week, be they heterosexual, homosexual, pedophiliac. They have these intercourses since birth, and since birth they can infect his or her neighbours and also be infected by her or his neighbours. At the beginning, the places are occupied with usual product probability (man or woman) and there is an arbitrary but finite number of people who are infected with HIV. They have sex with condoms, which they use properly. They behave according to this dynamics: If x is not in xi(t), then P(x is in xi(t+h)| F(t))=h*la* |neighbours of x, which are infected at time t |+o(h), if x is in xi(t), then P(x is not in xi(t+h)|F(t))=h+o(h), where x is any place, xi(t) is the set of HIV positive people at time t, F(t) is a sigma-algebra generated by trajectories in certain configuration space up to time t. I.e. everyone has intercourses with his or her neighbours, be they children, women or men, and at exponential times with intensity 4*la any person infects a neighbour chosen with uniform probability. Everyone who is infected dies after an exponential time with intensity 1. Everyone who dies, be it due to natural causes or due to AIDS, leaves behind one healthy offspring at the same place, the offspring immediately starts to have sex with his or her neighbours. We see that the situation of this depraved society can be described by the so called Contact process. Let us suppose the life expectancy of HIV positive person (which can vary substantially according to use of medicaments) is exponentially distributed with intensity 0.1, i.e. in average HIV positive person dies after 10 years.
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01-16-2002, 03:13 PM | #142 |
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Now look at these studies from
<a href="http://www.siecus.org/pubs/fact/fact0011.html" target="_blank">http://www.siecus.org/pubs/fact/fact0011.html</a> Condom use substantially reduces the risk of HIV transmission.12 A study published in The New England Journal of Medicine observed heterosexual couples where one was HIV-positive and the other was HIV-negative (sero-discordant couples), for an average of 20 months. Findings included13: No seroconversion occurred among the 124 couples who used condoms consistently and correctly for vaginal or anal intercourse.14 10 percent of the HIV-negative partners (12 of 121) couples became infected when condoms were used inconsistently for vaginal or anal intercourse.15 Of the 121 couples who used condoms inconsistently, 61 used condoms for at least half of their sexual contacts ad 60 rarely or never used condoms. The rate of seroconversion was 10.3 percent for the couples using condoms inconsistently and 15 percent for couples not using condoms.16 A study published in The Journal of Acquired Immune Deficiency Syndromes observed sero-discordant heterosexual couples and showed that only three out of 171 who consistently and correctly used condoms became HIV infected; eight out of 55 who used condoms inconsistently became HIV infected; and eight out of 79 who never used condoms became HIV infected.17 |
01-16-2002, 03:21 PM | #143 |
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So let us suppose from these data la=1/60. By rescaling the time, we obtain Contact process with la=1/6. Let us define la critical: lac=inf (la | P(|xi(t)|>0 for all t )>0). We see that if la<lac, the HIV infection disappears with probability one.
[ January 16, 2002: Message edited by: Ales ]</p> |
01-16-2002, 03:43 PM | #144 |
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How fast does it disappear? In dimension 1, exponentially fast, i.e.:
I apologize for dissecting my last post, the system does not want to accept it stating: Sorry, we do not permit this HTML tag: Parenthesis in HTML tag |
01-16-2002, 03:50 PM | #145 |
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P(xi(t) is not empty)
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01-16-2002, 04:02 PM | #146 |
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<= exp[-g t]
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01-16-2002, 04:04 PM | #147 |
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, g>0, something similar may hold in our case, i.e. in dimension 2. But what is the lac like? In Liggett it can be found, that in dimension one lac>=1.62, in higher dimension d: 1/(2d-1)<=lac<=2/d, in our case d=2, we see, that 1/6<1/3, i.e. the HIV infection will disappear, we also see that in dimension 3, i.e. everyone has sexual intercourse from birth until death with his or her 6 neighbours, if they use condoms properly, HIV disappears.
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01-16-2002, 06:15 PM | #148 | ||||
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In the conflict between Church and State U.S. Chief Justice Waite also wrote specifically, “In Regina v. Wagstaff (10 Cox Crim. Cases, 531), the parents of a sick child, who omitted to call in medical attendance because of their religious belief that what they did for its cure would be effective, were held not to be guilty of manslaughter, while it was said the contrary would have been the result if the child had actually been starved to death by the parents, under the notion that it was their religious duty to abstain from giving it food. But when the offence consists of a positive act which is knowingly done, it would be dangerous to hold that the offender might escape punishment because he religiously believed the law which he had broken ought never to have been made. No case, we believe, can be found that has gone so far.” In fact the specific issue is “the Free Exercise of Religion”, and not the Establishment clause. By the way, In McCollum v. Board of Education Justice Black wrote the majority opinion and didn’t site Reynolds v. U.S. nor did any of the assenting justices. It was Justice Reed (dissenting) that referenced Reynolds to support his dissent, “If abuses occur such as the use of the instruction hour for sectarian purposes, I have no doubt, in view of the Ring case, that Illinois will promptly correct them. If they are of a kind that tend to the establishment of a church or interfere with the free exercise of religion, this Court is open for a review of any erroneous decision. This Court cannot be too cautious in upsetting practices embedded in our society by many years of experience.” In other words Justice Reed opposed a broad decision precisely because it opened the Supreme Court to a flood of frivolous litigation with potentially devastating consequences, and such as been the case over the last 50 years. Quote:
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[ January 16, 2002: Message edited by: dk ]</p> |
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01-17-2002, 02:08 AM | #149 |
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dk: The Constitution was interpreted as a purely secular document in the Mid 20th Century. To this day there are blue laws and laws of blasphemy on the books of several states.
<shrug> So what? Nobody is denying religious influence on the law. The fact is that the US has been a secular state since its foundation. The Founding Fathers largely understood the Establishment Clause the same way we do, as extensive writings on it by Madison and Jefferson show. Separation of Church and State is a long and ongoing process. I see you are still avoiding the Treaty of Tripoli. In Reynold's the Court clearly advocated a secular position, but had to balance the fact that Christians opposed polygamy. The SC is always bumping up against the intolerance of Christianity -- a good example is the fantasy you're currently advocating, that the SC did not interpret the Constitution secularly until 1950. Take a gander at this from Reynolds you put up: "Laws are made for the government of actions, and while they cannot interfere with mere religious belief and opinions, they may with practices." A clear statement of secularism, even if the word itself is not used. Since Waite cited Jefferson's exact words on the "wall of separation," the only thing left to you is this strenuous state of denial you're in. <a href="http://members.tripod.com/~candst/caseadd.htm" target="_blank">http://members.tripod.com/~candst/caseadd.htm</a> Take Bloom v Cornelius, 1853 "Christianity is a part of the common law of England, but, under the provisions of our constitution, neither Christianity nor any other system of religion is a part of the law of this state." From the same holding: "We have no union of Church and State, nor has our government ever been vested with authority to enforce any religious observance simply because it is religious." From the same holding "The statute, prohibiting common labor on the Sabbath, could not stand for a moment as the law of this state, if its sole foundation was the Christian duty of keeping the day holy, and its sole motive to enforce the observance of that duty. It is to be regarded as a mere municipal or police regulation, whose validity is neither strengthened nor weakened by the fact that the day of rest it enjoins is the Sabbath day." As early as the 1870s state supreme courts began ruling that coerced school prayer was unconstitutional; when SCOTUS ruled on that in the 1940s, it was drawing on 70 years of precedents at the state level. So in the 19th century we have a clear trend, toward the development of a secular constitution, backed by the clear opinion of the Founding Fathers, and court rulings at many levels. This is a trend; certainly there were reversals, but the trend is clearly toward a secular nation. Michael |
01-17-2002, 04:22 AM | #150 | |
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