Gnome 2.19.1 Released

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On the road to 2.20.0 Gnome has just reached the 2.19.1 release. What does it bring new compared to 2.18? Well, first of all it brings new documentation and translations (maybe just in case the previous were not enough), new features and new bug-fixes. This is a development release though; so many modules still need improvements. The Gnome developers encourage Linux lovers to compile and test this new release and offer some for download and for some compiling tools. For example for compiling Gnome 2.19.1 you can use Garnome, which can be found here and the release should be found here along with the release notes.

The Gnome 2.19.1 developers announced this release as a snapshot of development code that is mainly intended for testing and hacking purposes. The release is though buildable and usable. You can join the Gnome project too. Any Linux fan willing to help with the Gnome development is more than welcomed here. You do not have to be a programmer to join this project, as there are also a lot of things to be improved that do not require programming knowledge.

The Gnome project aims to create an easy-to-use computing platform out of completely free software. The Gnome project gathers a lot of software and it is used in conjunction with an operating system such as Linux or Solaris. It is also part of the GNU operating system, being its official desktop environment.

Gnome was set-up in August 1997 by the GNU project as an alternative to the KDE software desktop environment that relied on the Qt widget toolkit, which did not use a free software license at that time. Gnome was intended to create a new desktop without making use of the Qt libraries. Thus, instead of Qt Gnome uses GTK+ toolkit under the GNU Lesser Public License (LPGL).

Low-Energy LED Lighting for Streets and Buildings

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A light-emitting diode (LED) is a semiconductor device that emits incoherent narrow-spectrum light through a form

of electroluminescence. LEDs are small extended sources with extra optics added to the chip, which emit a complex intensity spatial distribution. The color of the emitted light depends on the composition and condition of the semiconducting material used and can be infrared, visible or near-ultraviolet.

The Department of Trade and Industry-led Technology Programme in UK has funded a £175,000 ($350,000) grant to researchers at The University of Manchester to develop powerful low-cost LED lighting modules that can be used in buildings and on roads. Dialight Lumidrives - a company founded by a former student - is contributing another £175,000 to the scheme.

The main goal is to investigate how tightly packed groups of LEDs can be made to work safely and reliably, and with less energy consumption and lower sosts. LEDs lighting solutions have the potential to reduce energy consumption by between 25 and 50 per cent, depending on the applications.

Illumination applications using LEDs are already being used in advertising panels in the streets and for traffic lights, but their use in street and building lighting has yet to overcome some obstacles.

The technical ones involve thermal and electrical issues at the desired lighting levels (of 12,000 lumens and above, when a typical 60w household light bulb produces about 800 lumens), like the amount of heat generated by LEDs packed closely together.

Since the project aims to develop LED modules to be used outside, environmental factors will also be a concern, such as glare, pollution and even the possibility of a bird nesting over a vital heatsink.

Dr Roger Shuttleworth from the Power Conversion Group at The University of Manchester, said: "LED technology first came to prominence in instrument displays back in the 1970s, but we are increasingly seeing it used in things like traffic signals and car lights. Towards the end of the twentieth century, the old fashioned sodium street lights that made everything look orange were gradually replaced by high-pressure sodium lamps. While these are brighter and more aesthetically pleasing, and can help tackle street crime and anti-social behaviour, they are also less energy efficient. With the environment at the top of the public and political agenda, energy saving has become a very important issue. When you consider how many street lights there are in the UK alone, it's clear there are some big opportunities for energy and cost savings."

The many benefits of LEDs will include cutting energy consumption and overall running costs, reducing light pollution and the glow that radiates from big cities, and their longer lifespan which means they would need to be replaced less often, potentially cutting down on traffic disruption and local council repair bills.

Gold Nanoparticles Used to Detect a Toxic Metal - Mercury

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Throughout history, mercury has widely been used by alchemists that were trying to produce gold. Now, the roles have changed, and gold is what helps scientists find mercury.

In

the litmus test, litmus is a water-soluble mixture of different dyes extracted from certain lichens, especially Roccella tinctoria, often absorbed on to filter paper. The resulting piece of paper or solution with water becomes a pH indicator (one of the oldest), used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (alkaline) conditions, the color change occurring over the pH range 4.5-8.3 (at 25 degrees Celsius). Neutral litmus paper is purple in color.

Scientists at Northwestern University have recently developed a simple "litmus test" for mercury that could be used for environmental monitoring of bodies of water, such as rivers, streams, lakes and oceans, to evaluate their safety as food and drinking water sources.

The colorimetric screening technology and its success in detecting mercury rely on using gold nanoparticles and DNA.

Produced directly and indirectly as part of several industrial processes such as the manufacture of acetaldehyde, methyl mercury is a neurotoxin that is particularly dangerous to young children and pregnant women and the form of mercury people ingest when they eat contaminated fish and shellfish.

Mercury is released into the air through industrial pollution, falling into bodies of water and polluting the waters in which fish and shellfish live. Bacteria in the aquatic environment then convert water-soluble mercuric ion (Hg2+) into methyl mercury, which accumulates in varying amounts in fish and shellfish.

Chad A. Mirkin, George B. Rathmann Professor of Chemistry, Professor of Medicine and Professor of Materials Science and Engineering, who led the study, said that "It is critical to detect mercury quickly, accurately and at its source. Most existing detection methods require expensive complicated equipment forcing tests to take place in a lab. Our method is simpler, faster and more convenient than conventional methods, and results can be read with the naked eye at the point of use."

Being highly sensitive, they are capable of detecting mercuric ions at the 100 nanomolar level. "To the best of my knowledge, we have set a record for the most sensitive colorimetric sensor," said Mirkin. "A glucose meter, for example, operates at a high micromolar scale, with glucose being 100,000 times more concentrated than the mercury we are detecting."

Future applications using similar principles will include developing a colorimetric screening method for cadmium and lead.

Geographic Records of the Water

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Water is the blood of planet Earth and its circuit maintains it alive.

And this cycle implies rivers, lakes, seas and oceans.

Here are some of their records.

The largest running water

in the world is the Amazon river. Each second, this enormous river disgorges 150,000 cubic meters of water into the Atlantic Ocean (3,120 cubic km annually).

Amazon is also the longest river in the world (4,195 mi or 6,750 km), 50 mi (80 km) longer than the Nile, and it also has the largest river basin in the world: 7,050,000 square km (2/3 of Europe or double of the sum for Mississippi and Nile).

The second river is Congo and the third by debit is Ganges.

The largest river delta in the world is that formed by the Ganges and Brahmaputra (Bangladesh and northeastern India): 7,800,000 hectares.

The longest river estuary is that of Obi (Siberia): 450 mi (720 km).

The largest lake in the world is the Caspian Sea: 424,800 square km and 975 m maximum depth.

The deepest lake in the world is Baikal (Siberia): 1,620 m. It has 23,000 cubic km of water, and harbors 1,200 animal species and 700 plant species.

The largest gulf in the world is the Gulf of Mexico: 615,000 square mi (1.6 million square km).

The shortest known river is D.River, in Oregon, that enters into the Pacific after just 132 m (440 ft).

The highest waterfall in the world is the Angel Falls (Venezuela): 979 m (3,212 ft) tall.

The biggest geyser in the world is “Old Faithful” from Yellowstone National Park (Wyomong, US): its water column is 30-54 m (100-180 ft) tall and erupts from 21 to 65 minutes.

The saltiest ocean is the Atlantic: 3.5 % salts, and amongst the seas, the record is detained by the Red Sea : 4 %.

The warmest seawater is that of the Persian Gulf: 35 degrees C, followed by the Red Sea: 32 degrees C.

The coldest seawater is that of the Ross and Weddell seas (Antarctica).

The strongest marine current is the Gulf Stream: it carries 82 million cubic meters of water per second.

The widest strait is the Yucatan Channel between Yucatan peninsula (Mexico) and Cuba: 220 km (360 mi).

It is also the deepest: 2,000 m (6,660 ft).

The longest strait is the Straits of Malacca, between Sumatra Island and Malacca peninsula: 805 km (500 mi) long.

The narrowest intercontinental strait is Bosporus (between Europe and Asia): 700-750 m wide (0.5 mi) and 80 km (50 mi) long.

The narrowest navigable strait in the world is Khalkis (Aegean Sea), between the Balkan peninsula and Eubea island: 40 m (133 ft).

The largest fjord in the world is Northwestern, located in ...eastern Greenland: 313 km (195 mi) long.

Geographic Records of the Water

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Water is the blood of planet Earth and its circuit maintains it alive.

And this cycle implies rivers, lakes, seas and oceans.

Here are some of their records.

The largest running water

in the world is the Amazon river. Each second, this enormous river disgorges 150,000 cubic meters of water into the Atlantic Ocean (3,120 cubic km annually).

Amazon is also the longest river in the world (4,195 mi or 6,750 km), 50 mi (80 km) longer than the Nile, and it also has the largest river basin in the world: 7,050,000 square km (2/3 of Europe or double of the sum for Mississippi and Nile).

The second river is Congo and the third by debit is Ganges.

The largest river delta in the world is that formed by the Ganges and Brahmaputra (Bangladesh and northeastern India): 7,800,000 hectares.

The longest river estuary is that of Obi (Siberia): 450 mi (720 km).

The largest lake in the world is the Caspian Sea: 424,800 square km and 975 m maximum depth.

The deepest lake in the world is Baikal (Siberia): 1,620 m. It has 23,000 cubic km of water, and harbors 1,200 animal species and 700 plant species.

The largest gulf in the world is the Gulf of Mexico: 615,000 square mi (1.6 million square km).

The shortest known river is D.River, in Oregon, that enters into the Pacific after just 132 m (440 ft).

The highest waterfall in the world is the Angel Falls (Venezuela): 979 m (3,212 ft) tall.

The biggest geyser in the world is “Old Faithful” from Yellowstone National Park (Wyomong, US): its water column is 30-54 m (100-180 ft) tall and erupts from 21 to 65 minutes.

The saltiest ocean is the Atlantic: 3.5 % salts, and amongst the seas, the record is detained by the Red Sea : 4 %.

The warmest seawater is that of the Persian Gulf: 35 degrees C, followed by the Red Sea: 32 degrees C.

The coldest seawater is that of the Ross and Weddell seas (Antarctica).

The strongest marine current is the Gulf Stream: it carries 82 million cubic meters of water per second.

The widest strait is the Yucatan Channel between Yucatan peninsula (Mexico) and Cuba: 220 km (360 mi).

It is also the deepest: 2,000 m (6,660 ft).

The longest strait is the Straits of Malacca, between Sumatra Island and Malacca peninsula: 805 km (500 mi) long.

The narrowest intercontinental strait is Bosporus (between Europe and Asia): 700-750 m wide (0.5 mi) and 80 km (50 mi) long.

The narrowest navigable strait in the world is Khalkis (Aegean Sea), between the Balkan peninsula and Eubea island: 40 m (133 ft).

The largest fjord in the world is Northwestern, located in ...eastern Greenland: 313 km (195 mi) long.

Tiny Machines Made of Microbes

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Biomimetics employs organisms as models for building new machines.

But now new machines could be made of organisms. In fact, tiny machines from microorganisms.

The single-celled Spirostomum, a Paramecium-related protozoan, resembling a tiny brown worm, can contract its 0.5 mm-long body to 25% of its length

in a millisecond: this is the fastest known movement in a microorganism.

Many microorganisms are integrated in MEMS (Microelectromechanical Systems) technology, the so-called “biotic-MEMS,” developing micron-level machines.

A team of University of Washington has realized a catalogue of the most promising microorganisms (all less than 1 mm long and made of one or few cells) for MEMS systems, and which can boost the conventional MEMS technology. “Tools and concepts have been increasingly borrowed from biology to solve technology problems. Biological concepts such as self-assembly are under serious consideration by technologists now for making highly integrated nano and micro systems”, said co-author Babak Parviz, an electrical engineer.

The microorganisms were assigned into four employment fields: material synthesis, precise structure formation, as functional devices, and integrated into controllable systems. Through biomineralization, a process detected in 700 million years old rocks, microorganisms can produce at least 64 different inorganic materials employed in MEMS technology, like silicon dioxide, biogenic calcite, magnets, gold and silver crystals.

Magnetic bacteria produce magnetosome crystals, crucial for the heading of their water movements.

Unlike industrial MEMS synthesis methods, requiring high temperatures, corrosive gases, vacuums and plasma, microorganisms produce the materials at room temperature, at near-neutral pH, in water solutions.

These structures made by microbes can develop into three dimensions and can be changed with nanoscale or macroscopic (visible scale) precision.

The spicules in the skeleton walls of one deep-sea sponge have excellent fiber-optical properties.

The fields of the chemical and biological sensors (for food and environmental monitoring) could employ microorganisms, as they evolved to detect specific chemicals. “One of the most interesting applications of MOs [microorganisms] in MEMS is to directly use them for detecting chemicals. MOs can be genetically engineered to have various receptors. All the transduction and amplification machinery is already in MOs. I think integration of these MOs into MEMS platforms can generate extremely powerful chemical/biological analysis systems”, said Parviz.

There are microbes that turn chemical energy into electrical energy, like the environmentally-friendly Microbial Fuel Cells for powering robotics and biomedical devices, and for economic hydrogen production, replacing small conventional batteries.

The biggest challenge by now is to integrate these devices into controllable micron-scale systems. “Our ability to manipulate small organisms and produce platforms that can interface with them one cell at a time is brand new. It is yet to be seen how researchers will take advantage of these new capabilities”, Parviz added.

Linux Kernel 2.6.21 Released

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After two and a half months from the last release, Linus Torvalds has just announced today the final and stable release of the Linux kernel, version 2.6.21. The biggest change in 2.6.21 is all the timer changes to support a tickless system:

"If the goal for 2.6.20 was to be a stable release (and it was), the goal for 2.6.21 is to have just survived the big timer-related changes and some of the other surprises (just as an example: we were apparently unlucky enough to hit what looks like a previously unknown hardware errata in one of the ethernet drivers that got updated etc). [...] So the big change during 2.6.21 is all the timer changes to support a tickless system (and even with ticks, more varied time sources). Thanks (when it no longer broke for lots of people ;) go to Thomas Gleixner and Ingo Molnar and a cadre of testers and coders." - says Linus Torvalds.

Highlights of this release include:

• VMI (Virtual Machine Interface)
• KVM updates
• Dynticks and Clockevents
• ALSA System on Chip (ASoC) layer
• Dynamic kernel command-line
• Optional ZONE_DMA
• devres (optional subsystem for drivers)
• GPIO API

Here come the new drivers:

Graphics:

• Add fbdev driver for the old S3 Trio/Virge
• Driver for the Silicon Motion SM501 multifunction device framebuffer subsystem,

Storage devices:

• Add two drivers for the it8213 IDE device, one using the old IDE stack, and other using libata
• Add IDE Driver for Delkin/Lexar/etc.. cardbus CF adapter
• Add IDE driver for Toshiba TC86C001 (old IDE stack)
• Add SCSI driver for SNI RM 53c710
• Add driver for Initio 162x SATA devices

Networking devices

• Add driver for the latest 1G/10G Chelsio adapter, T3,
• Add driver for the Attansic L1 ethernet device
• Add driver for the Gigaset M101 wireless ISDN device
• Add PC300too alternative WAN driver
• Add driver for Silan SC92031 device
• Add driver for the Davicom DM9601 USB 1.1 ethernet device

Various

• Add driver to charge USB blackberry devices
• Add driver for iowarrior USB devices.
• Add support for the GTCO CalComp/InterWrite USB tablet
• New driver for the Analog Devices ADM1029 hardware monitoring driver

For a full change-log with all the new features, drivers and improvements, please visit this website.

The Linux Kernel is the essential part of all Linux Distributions, responsible for resource allocation, low-level hardware interfaces, security, simple communications, and basic file system management.

Linux is a clone of the operating system Unix, initially written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. It aims towards POSIX and Single UNIX Specification compliance.

You can download the Linux kernel now from Softpedia.