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1.: Artikel menarik dari APS news:The Future of Science From: zxabidin

2.: [artikel chem-is-try.org] Unsur-unsur toksik dalam asap rokok From: mr.soetrisno

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1.: Artikel menarik dari APS news:The Future of Science

Posted by: "zxabidin" zxabidin@yahoo.com zxabidin

Fri Nov 21, 2008 5:11 pm (PST)

The Future of Science: Building a Better Collective Memory

By Michael A. Nielsen
When Robert Hooke discovered his law of elasticity in 1676, he didn't
publish it in the ordinary way. Instead, he published it as an
anagram: "ceiiinosssttuv." He revealed this two years later as the
Latin ut tensio, sic vis, meaning "as the extension, so the force."
This ensured that if someone else made the same discovery, Hooke could
reveal the anagram and claim priority, thus buying time in which he
alone could build upon the discovery.

Many great scientists of the age, including Leonardo, Galileo and
Huygens, used anagrams or ciphers for similar purposes. The Newton-
Leibniz controversy over who invented calculus occurred because Newton
claimed to have invented calculus in the 1660s and 1670s, but didn't
publish until 1693. In the meantime, Leibniz developed and published
his own version of calculus.

Such secrecy was natural in a society in which there was often little
personal gain in sharing discoveries. This secrecy faded because the
great scientific advances in the time of Hooke and Newton motivated
wealthy patrons such as the government to begin subsidizing science as
a profession. Because the public benefit delivered by scientific
discovery was strongest if discoveries were shared, the result was a
scientific culture that to this day rewards the sharing of
discoveries. Today, when a scientist applies for a job, the most
important part of the application is often their published scientific
papers.

The adoption and growth of the scientific journal system has created a
body of shared knowledge for our civilization, a collective long-term
memory that is the basis for much of human progress. This system has
changed surprisingly little in the last 300 years. The Internet offers
us the first major opportunity to improve this collective long-term
memory, and to create a collective short-term working memory, a
conversational commons for the rapid collaborative development of
ideas.

One way of viewing online tools is as a way of expanding the range of
scientific knowledge that can be shared with the world. A successful
example is the physics preprint arXiv, which lets physicists share
preprints of their papers without the months-long delay typical of a
conventional journal. More radically, the internet can also change the
process and scale of creative collaboration, using social software
such as wikis, online forums, and similar tools. I believe that such
tools and their descendants will change scientific collaboration more
over the next 20 years than it has changed in the past 300 years. Yet,
with the exception of email, scientists currently appear puzzlingly
slow to adopt many online tools. This is a consequence of some major
barriers deeply embedded within the culture of science.

Two Failures of Science Online

Inspired by the success of Amazon.com's review system and similar
sites, many organizations have created comment sites where scientists
can share their opinions of scientific papers. Perhaps the best-known
was Nature's 2006 failed trial of open commentary on papers being peer
reviewed at Nature. To date, none of the sites have succeeded.

The problem is that while thoughtful commentary on scientific papers
is useful for other scientists, there are few incentives for people to
write such comments. Why write a comment when you could be doing
something more "useful," like writing a paper or a grant? Furthermore,
if you publicly criticize someone's paper, there's a chance that
person may be an anonymous referee in a position to scuttle your next
paper or grant application.

Contrast this with the approximately 1500 reviews of Pokemon you'll
find at Amazon.com. We have a ludicrous situation where popular
culture is open enough that people feel comfortable writing Pokemon
reviews, yet scientific culture is so closed that people will not
publicly share their opinions of scientific papers. Some people find
this curious or amusing; I believe it signifies something seriously
amiss with science that needs to change.

Wikipedia is a second example where scientists have missed an
opportunity to innovate online. Wikipedia has a vision statement to
warm a scientist's heart: "Imagine a world in which every single human
being can freely share in the sum of all knowledge. That's our
commitment." You might guess Wikipedia was started by scientists eager
to collect all of human knowledge into a single source. In fact,
Wikipedia's founder, Jimmy Wales, had a background in finance and as a
web developer. In the early days few established scientists were
involved. To contribute would arouse suspicion from colleagues that
you were wasting time that could be spent writing papers and grants.

Some scientists will object that contributing to Wikipedia isn't
really science. It's not if you take it for granted that science is
only about publishing in specialized scientific journals. But if you
believe science is about discovering how the world works, and sharing
that understanding with the rest of humanity, then the lack of early
scientific support for Wikipedia looks like an opportunity lost.
Nowadays, Wikipedia's success has to some extent legitimized
contribution within the scientific community. But how strange that the
modern day Library of Alexandria had to come from outside academia.

An Open Scientific Culture

The value of openness was understood centuries ago by many of the
founders of modern science; indeed, the journal system is perhaps the
most open system for the transmission of knowledge that could be built
with 17th century media. The adoption of the journal system was
achieved by subsidizing scientists who published their discoveries in
journals. This same subsidy now inhibits the adoption of more
effective technologies.

We should aim to create an open scientific culture where as much
information as possible is moved out of people's heads and labs, onto
the network, and into tools that can help us structure and filter the
information: data, scientific opinions, questions, ideas, folk
knowledge, workflows, and everything else. Information not on the
network can't do any good.

One way to achieve cultural change is via the top-down strategy that's
been successfully used by the open access (OA) movement. The goal of
OA is to make scientific research freely available online to everyone
in the world. In April 2008 the National Institutes of Health mandated
that every paper written with the support of their grants must
eventually be made open access. This is the scientific equivalent of
successfully storming the Bastille.

The second strategy is bottom-up. It requires that the people building
the new online tools also develop and boldly evangelize ways of
measuring the contributions made with the tools. As an example, since
1991 physicists have been uploading their papers to the physics
preprint arXiv, often at about the same time as they submit to a
journal. The arXiv is not refereed, although a quick check is done by
arXiv moderators to remove crank submissions. In many fields, most
papers appear on arXiv first, and many physicists start their day by
seeing what's appeared on the arXiv overnight.

After the arXiv began, a service for particle physics called SPIRES-
HEP extended their citation tracking to include both arXiv papers and
conventional journal articles. As a result, it's now possible to
search on a particle physicist's name, and see how frequently all
their papers, including arXiv preprints, have been cited by other
physicists.

SPIRES-HEP has been run since 1974 by the Stanford Linear Accelerator
Center (SLAC). SLAC's metrics of citation impact are both credible and
widely used by the particle physics community. When physics hiring
committees meet to evaluate candidates in particle physics, people
often have their laptops out, examining and comparing the SPIRES-HEP
citation records of candidates. The result is a small but genuine
cultural change towards more openness in science, achieved using the
bottom-up strategy.

The Problem of Collaboration

When doing research, subproblems constantly arise in unexpected areas.
No one can be expert in all those areas. Most of us instead stumble
along, picking up the skills necessary to make progress towards our
larger goals. We have a small group of trusted collaborators with whom
we exchange questions and ideas when we are stuck. They may point us
in the right direction, but rarely do they have exactly the expertise
we need. Might it be possible to use online tools to scale up this
conversational model, and build an online collaboration market to
exchange questions and ideas, a sort of collective working memory for
the scientific community?

To see how much is lost due to inefficiencies in the current system of
collaboration, imagine a scientist named Alice. Many of Alice's
research projects spontaneously give rise to problems in areas in
which she isn't expert. Suppose that for a particular problem, Alice
estimates that it would take her four to five weeks to acquire the
required expertise and solve the problem. So the problem is on the
backburner. Unbeknownst to Alice, though, there is another scientist
in another part of the world, Bob, who has just the skills to solve
the problem in less than a day.

Unfortunately, nine times out of ten they never even meet, or if they
do, they just exchange small talk. It's an opportunity lost for a
mutually beneficial trade, a loss that may cost weeks of work for
Alice. It's also a great loss for the society that bears the cost of
doing science. Expert attention, the ultimate scarce resource in
science, is very inefficiently allocated under existing practices for
collaboration.

An efficient collaboration market would enable Alice and Bob to find
this common interest, and exchange their know-how, in much the same
way eBay and craigslist enable people to exchange goods and services.
However, in order for this to be possible, a great deal of mutual
trust is required. Without such trust, there's no way Alice will be
willing to advertise her questions to the entire community.

Let's compare this situation to the apparently very different problem
of buying shoes. Alice walks into a shoe store, with some money. Alice
wants shoes more than she wants to keep her money; Bob the shoe store
owner wants the money more than he wants the shoes. As a result, Bob
hands over the shoes, Alice hands over the money, and everyone walks
away happier after just ten minutes. This rapid transaction takes
place because there is a trust infrastructure of laws and enforcement
in place that ensures that if either party cheats, they are likely to
be caught and punished.

If shoe stores operated like scientists trading ideas, first Alice and
Bob would need to get to know one another, maybe go for a few beers in
a nearby bar. Only then would Alice say, "You know, I'm looking for
some shoes." After a pause, and a few more beers, Bob would say "You
know what, I just happen to have some shoes I'm looking to sell."
Every working scientist recognizes this dance; I know scientists who
worry less about selling their house than they do about exchanging
scientific information.

In economics, it's been understood for hundreds of years that wealth
is created when we lower barriers to trade, provided there is a trust
infrastructure of laws and enforcement to prevent cheating and ensure
trade is uncoerced. The basic idea, which goes back to David Ricardo
in 1817, is to concentrate on areas where we have a comparative
advantage, and to avoid areas where we have a comparative
disadvantage.

Ricardo's analysis works equally well for trade in ideas. Indeed, even
were Alice to be far more competent than Bob, both Alice and Bob
benefit if Alice concentrates on areas where she has the greatest
comparative advantage, and Bob on areas where he has less comparative
disadvantage. Unfortunately, science currently lacks the trust
infrastructure and incentives necessary for such free, unrestricted
trade of questions and ideas.

An ideal collaboration market will enable just such an exchange of
questions and ideas. It will bake in metrics of contribution so
participants can demonstrate the impact their work is having.
Contributions will be archived, timestamped, and signed, so it's clear
who said what, and when. Combined with high quality filtering and
search tools, the result will be an open culture of trust that gives
scientists a real incentive to outsource problems, and contribute in
areas where they have a great comparative advantage, fundamentally
changing how science is done.

Michael Nielsen is a writer working on a book about the future of
science. For information about the book, see Michael Nielsen's Blog.
In a past life he helped pioneer the field of quantum computation, and
was the author of more than 50 scientific papers. The above article is
adapted from an essay appearing on his blog, based on his keynote talk
at the New Communication Channels for Biology workshop, San Diego,
June 26 and 27, 2008. Full version of keynote talk.

©1995 - 2008, AMERICAN PHYSICAL SOCIETY
APS encourages the redistribution of the materials included in this
newspaper provided that attribution to the source is noted and the
materials are not truncated or changed.

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2.: [artikel chem-is-try.org] Unsur-unsur toksik dalam asap rokok

Posted by: "mr.soetrisno" chemcafe@yahoo.com mr.soetrisno

Fri Nov 21, 2008 6:37 pm (PST)

Kategori Kimia Lingkungan
Unsur-unsur toksik dalam asap rokok
Oleh Soetrisno

Logam-logam berat seperti arsenik, kadmium, dan timbal telah dideteksi
dalam asap rokok,dengan menunjukkan bahwa unsur-unsur toksik ini bisa
merambat sampai jarak berbeda-beda alam aliran udara.

Rokok yang sedang terbakar menghasilkan lebih dari 4000 zat kimia;
banyak diantaranya yang bersifat toksik dan sekitar 40 menyebabkan
kanker. Senyawa-senyawa ini tetap berada di udara sebagai asap
tembakau lingkungan yang dihirup oleh orang lain di kawasan tersebut.
Ada dua tipe asap rokok, yaitu: asap rokok utama yang keluar dari
mulut perokok dan asap sampingan yang berasal dari ujung rokok yang
terbakar.

Ketika meneliti logam-logam berat dalam asap rokok sampingan, para
peneliti di perusahaan rokok Philip Morris, US, menemukan tumpukan
arsenik dalam cerobong asap yang digunakan dalam tahap pertama pada
peralatan mereka. Fenomena ini tidak ditemukan untuk kadmium atau
timbal. Mereka menganggap bahwa yang menyebabkan ini terjadi adalah
bahwa arsenik bisa menjadi uap cair sedangkan kadmium dan timbal
adalah partikulat padat.

[selengkapnya] http://www.chem-is-try.org/?sect=artikel&ext=220

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