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.

Blog Timezone: America/Los_Angeles [Winter: -0800 hhmm | Summer: -0700 hhmm] 
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2007-03-27

2007-03-26

Molecular Tools Make the Cut


Molecular Tools Make the Cut from PhysOrg.com

Researchers in Japan have developed a pair of molecular-scale scissors that open and close in response to light. The tiny scissors are the first example of a molecular machine capable of mechanically manipulating molecules by using light, the scientists say.

[Continued]




Chronos Time Zone Repository Version 2007d Published

Version 2007d of the Chronos Time Zone Repository has been published. It is based on version 2007d of the Olson Time Zone Database.

Downloads:




2007-03-23

Negative Refraction of Visible Light Demonstrated; Could Lead to Cloaking Devices


Negative Refraction of Visible Light Demonstrated; Could Lead to Cloaking Devices from PhysOrg.com

For the first time, physicists have devised a way to make visible light travel in the opposite direction that it normally bends when passing from one material to another, like from air through water or glass. The phenomenon is known as negative refraction and could in principle be used to construct optical microscopes for imaging things as small as molecules, and even to create cloaking devices for rendering objects invisible.

[Continued]




Monarch system-on-a-chip excels in early testing


Monarch system-on-a-chip excels in early testing from PhysOrg.com

A revolutionary processor package that changes its architecture to adapt to the demands of different computing tasks more than met design expectations in recent trials.

[Continued]




2007-03-21

Scientists create microscopic alphabet


Scientists create microscopic alphabet from PhysOrg.com

UCLA scientists have designed and mass-produced billions of fluorescent microscale particles in the shapes of all 26 letters of the alphabet in an “alphabet soup” displaying “exquisite fidelity of the shapes.”

[Continued]





Mechanics meets chemistry in new way to manipulate matter


Mechanics meets chemistry in new way to manipulate matter from PhysOrg.com

The inventors of self-healing plastic have come up with another invention: a new way of doing chemistry. Researchers at the University of Illinois at Urbana-Champaign have found a novel way to manipulate matter and drive chemical reactions along a desired direction.

[Continued]




2007-03-20

Which country has the most time zones?

I recently noticed quite a few hits on my website from people who wanted to know which country has the most time zones. I assume this was a school assignment of some sort.

The answer depends on the definition of "time zone." If a "time zone" is defined as simply an offset from Universal Time, then the answer is Russia (which has 11 different time zone offsets.) If a "time zone" is defined as "a location where the rules that determine the offset from moment to moment have been the same since at least 1970 or earlier" (which is the definition used by the Olson Time Zone Database, and is the one usually meant,) then the answer is the United States (which has 25 such time zones.)

Most countries only have one time zone, using either definition. Using the Olson definition, the only countries with more than one time zone are the United States, Russia, Canada, Australia, Greenland, Argentina, Brazil, Chile, Ecuador, Paraguay, Spain, Congo (Democratic Republic,) Mexico, Ukraine, Kazakhstan, Uzbekistan, Mongolia, China, Malaysia, Indonesia, New Zealand, French Polynesia, Micronesia and Kiribati.


2007-03-18

The universe is a string-net liquid

From New Scientist:

In 1998, just after he won a share of the Nobel prize for physics, Robert Laughlin of Stanford University in California was asked how his discovery of "particles" with fractional charge, now called quasi-particles, would affect the lives of ordinary people. "It probably won't," he said, "unless people are concerned about how the universe works."

Well, people were. Xiao-Gang Wen at the Massachusetts Institute of Technology and Michael Levin at Harvard University ran with Laughlin's ideas and have come up with a prediction for a new state of matter, and even a tantalising picture of the nature of space-time itself. Levin presented their work at the Topological Quantum Computing conference at the University of California, Los Angeles, early this month.


Continued...


2007-03-14

New Micromanipulator May Help Build Micro-Machines


New Micromanipulator May Help Build Micro-Machines from PhysOrg.com

Future microscopic-sized machines assembled with micrometer or nanometer-scale parts will need to be made with devices that use tiny, agile "fingers" that can grip, lift and do the assembly work in a controlled, coordinated way.

[Continued]




2007-03-13

Buildup of damaged DNA in cells drives aging


Buildup of damaged DNA in cells drives aging from PhysOrg.com

The accumulation of genetic damage in our cells is a major contributor to how we age, according to a study being published today in the journal Nature by an international group of researchers. The study found that mice completely lacking a critical gene for repairing damaged DNA grow old rapidly and have physical, genetic and hormonal profiles very similar to mice that grow old naturally.

[Continued]




2007-03-12

Physicists Modify Double-Slit Experiment to Confirm Einstein's Belief


Physicists Modify Double-Slit Experiment to Confirm Einstein's Belief from PhysOrg.com

Work completed by physics professors at Rowan University shows that light is made of particles and waves, a finding that refutes a common belief held for about 80 years.

[Continued]




2007 North American DST Changes: Resources & References (2)

Due to the changes at Planet Smalltalk, which have invalidated all URLs to old articles, and due to the fact that Google searches are still preferentially returning results to now-invalid URLs at Planet Smalltalk, I am republishing the following information:


The Chronos Date/Time Library has had the correct DST rules for North America since 2005-08-22 (a year and a half ago.)


2007-03-08

Last Preparations Being Made for DST Bug


Last Preparations Being Made for DST Bug from PhysOrg.com

(AP) -- Normally the switch to daylight-saving time isn't a big deal, but this Sunday, Jeff Ronner has to put people on the case.
...
"There's a lot to consider," Ronner said. "Something that seems as simple as turning a clock back has amazing and extensive implications in everything you touch here, because so many things are date- and time-stamped."

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2007-03-06

2007 North American DST Changes: Resources & References


The Chronos Date/Time Library has had the correct DST rules for North America since 2005-08-22 (a year and a half ago.)


Scientists explain inception of perception in the brain

[The title is misleading: The article discuses a solution to the puzzle as to why (physically) cortical cells are quickly silenced in responise to stimulation from the thalamus.]


Scientists explain inception of perception in the brain from PhysOrg.com

The taste of champagne, the sound of a train, the flash of a pop fly into left field – indeed all of human perception – begins in the brain’s center. That’s where sensory information passes from the thalamus to the neocortex for processing.

[Continued]