Chronos is one of the many Smalltalk-related blogs syndicated on Planet Smalltalk
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Discussion of the Essence# programming language, and related issues and technologies.

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2006-09-30

Entanglement unties a tough quantum computing problem


Entanglement unties a tough quantum computing problem from PhysOrg.com

Error correction coding is a fundamental process that underlies all of information science, but the task of adapting classical codes to quantum computing has long bumped up against what seemed to be a fundamental limitation.

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2006-09-28

Powerful Batteries That Assemble Themselves

The article Powerful Batteries That Assemble Themselves (MIT Technology Review) discusses a research project that has been using "viruses to assemble battery components that can store three times as much energy as traditional materials by packing highly ordered materials into a very small space."

The author of the article apparently believes that the major portent of this research is improved functionality of batteries. I strongly disagree.

It's not that better batteries aren't important. It's just that the ability to manufacture materials, substances, medicines, devices, tools and other artifacts using controlled molecular assembly is far more important. And the existence proof that viruses can be used to do controlled molecular assembly, at least in some cases, is a very significant milestone in the evolotion of human technical abilities. Compared to that, better batteries are a footnote.


2006-09-26

55,000 tiny Thomas Jeffersons show power of new method


55,000 tiny Thomas Jeffersons show power of new method from PhysOrg.com

Ever since the invention of the first scanning probe microscope in 1981, researchers have believed the powerful tool would someday be used for the nanofabrication and nanopatterning of surfaces in a molecule-by-molecule, bottom-up fashion. Despite 25 years of research in this area, the world has hit a brick wall in developing a technique with commercial potential -- until now.

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2006-09-24

Engine on a chip promises to best the battery

Engine on a chip promises to best the battery from PhysOrg.com

MIT researchers are putting a tiny gas-turbine engine inside a silicon chip about the size of a quarter. The resulting device could run 10 times longer than a battery of the same weight can, powering laptops, cell phones, radios and other electronic devices.

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2006-09-18

Julian Day 2,454,000

At noon of 21 September 2006 begins Julian Day Number 2,454,000. A day and a half later, the Autumnal Equinox will occur (2006-09-23T04:03 Universal Time.)

The Hebrew New Year starts at sundown on 22 September (a.k.a Rosh Hoshana.) Note that the first month of the Hebrew year is traditionally known as the seventh month, not the first month.

Julian Day Numbers are an integer count of days since a specific epoch date. Julian Day Zero begins at Noon on 14 November 4714 BC, according to the proleptic Gregorian Calendar--or at Noon on 1 January 4713 BC, according to the proleptic Julian Calendar. Julian Day Zero was a Monday.

A Julian Date is a count of days, including any fractional part of the day, since -4713-11-24T12:00:00+0000 (24 Nov -4713 12:00:00 Universal Time, using Astronomical year numbering, where the year prior to the year 0001 is the year 0000, and not the year 1 BC, as would be traditional.)

It is common, but nevertheless technically incorrect, to refer to an ordinal date (Year-DayOfYear) as a "Julian Date."

Using a Julian Day Number to specify a date, or a Julian Date to specify a precise point in time, is useful for two reasons:

1) It permits dates to specified without reference to any particular calendrical system; and

2) It vastly simplifies astronomical calculations, and other computations where the amount of time between two dates needs to be computed.

The Julian Day system of specifying dates was invented by the astronomer Joseph Scaliger in 1583 (the year after the Gregorian Calendar Reform was put into effect in the Catholic countries of Europe.)

The epoch day of the Julian Day system was chosen to be the most recent day on which three calendrical cycles all were at their respective zero points. The three cycles are the 15-year Indiction Cycle (important in Roman tax law,) the 19-year Metonic Cycle (important for obtaining approximate synchronization of lunar and solar calendars,) and the 28-year Solar Cycle (all possible patterns of Julian Calendar dates and days-of-the-week recur once every 28 years.)

The "Julian" in "Julian Day" refers to Scaliger's father, and not to either Julius Caesar or to the Julian Calendar.

Julian Day 2,454,000 corresponds to the following dates in selected calendars (as computed by the Chronos Date/Time Library):

2006-09-21 AD [Gregorian]
0163-10-14 BE [Bahai]
1723-01-11 AM [Coptic]
1999-01-11 ZH [Ethiopic]
5766-06-28 AM [Hebrew]
1928-06-30 AS [Indian Civil]
1427-08-27 AH [Islamic (Fatimid)]
2006-09-08 AD [Julian]
2759-09-08 AUC [Julian (Imperial)]
1385-06-30 AP [Persian]
6242-09-30 SY [Solarian]
2006-264 [Gregorian-ordinal date]
2006-W38-4 [ISO]
J.D. 2454000 [Julian Day]
732574 days since Gregorian Epoch (1 January 0001 AD)
38614:00:00:00 days:hh:mm:ss.s.. since 1901-01-01T00:00:00Z (ST80 epoch)
1158796800 seconds since 1970-01-01T00:00:00Z (Unix epoch)
128032704000000000 100-nanosecond ticks since 1601-01-01T00:00:00Z (MS WIndows epoch)


Studies Find General Mechanism of Cellular Aging

According to the article Studies Find General Mechanism of Cellular Aging (Physorg.com,) "three separate studies confirm a gene that suppresses tumor cell growth also plays a key role in aging."

The studies found that as the concentration(hence, the rate of gene expression) of the protein p16INK4a in a stem cell increases, the more the stem cell has the characteristics and behaviors of senescence (being aged.) Stem cells lose their ability to divide and replenish themselves as they age, and this loss of function was proven to be a result of the increased expression of the p16INK4a gene.

The implications are that a) aging-related diseases are the result of an ever-increasing inability of stem cells to replenish tissue, and b) since upregulation of a single gene is the culprit, it may be easier than is commonly imagined to develop anti-aging therapies that have dramatic effects (even if they don't provide a total "cure" for aging.)


Version 2006k of the Chronos Time Zone Repository has been published

Arthur David Olson has published version 2006k of the Olson Time Zone Database. Consequently, version 2006k of the Chronos Time Zone Repository has been published--both the Chronos-native and XML versions are available from date-time-zone.com.


2006-09-15

Scientists Discover Memory Molecule

The Science Daily article Scientists Discover Memory Molecule discusses the discovery of a molecule, the enzyme protein kinase M zeta, that preserves long-term memories through persistent strengthening of synaptic connections between neurons. Memories can be erased by inhibiting the enzyme.

This discovery elevates from theory to fact the idea that long term memory is realized in the relative strengths of synaptic connections. Incidently, it also elevates from theory to fact the idea that memories are physically stored in neurons, as opposed to any non-physical explanation.

So now we know what molecular structures must survice cyronic suspension, and/or what molecular structures must be reconstructed when reviving cryonic suspension patients, in order for cryonic suspension/reanimation to preserve memory.


2006-09-09

Atomic Clocks Are Getting More Precise


Atomic Clocks Are Getting More Precise from PhysOrg.com

(AP) -- Some physicists are creating a revolution in the arcane world of ultra-precise clocks. And among them is a researcher who has trouble getting anywhere on time. "I do tend to be a little bit late," said Jim Bergquist, 58. "Quite a bit late."

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