Wireless for universal telecoms access

Basic mobile telephone has done a wonderful job of empowering Africa. A subsistence farmer growing a larger crop can now negotiate a price for his tomatoes before picking them and going to market. Information is power and the middle-man can be kept in his place without holding the poor farmer to ransom because of his ability to make a phone call on his prepaid mobile phone.

Of the 800-million inhabitants in Africa approximately 600-million are subsistence farmers. They want to improve their lot. Ubiquitous coverage with 3G networks will do a lot to give the New Partnership for Africa’s Development a kick start. Then the farmer will be able to “surf” the web on his mobile phone at a lower cost to see how better to grow his tomatoes; improve crop yields and produce better cattle. Next generation wireless technologies offer a tremendous opportunity for providing access to global telecommunications at a profit to the operators. The African CDMA Forum (ACF) is an African trade association serving Africa’s CDMA fixed and mobile member community by promoting, protecting and enhancing their interests and investments. For further details on the ACF and how to join see www.3gafrica.org. This website gives links to the technologies discussed in this paper.

 

The 3G standard

 

3G stands for third-generation wireless technology and networks. It is based on the International Telecommunication Union (ITU) initiative for a single global wireless standard called International Mobile Telecommunications-2000 (IMT 2000). This concept of a single standard evolved into a family of five 3G wireless standards. Of those five, the most widely accepted are CDMA2000, WCDMA (UMTS) and TD-SCDMA. According to the ITU and IMT-2000, a wireless standard must meet minimum bit-rate requirements to be considered 3G:

• 2 Mbps in fixed or in-building environments

• 384 kbps in pedestrian or urban environments

• 144 kbps in wide area mobile environments

• Variable data rates in large geographic area systems (satellite)

In addition to providing faster bit rates and greater capacity over previous generation technologies, 3G standards excel by effectively:

• Delivering mobile data

• Offering greater network capacity

• Operating with existing second-generation technologies

• Enabling rich data applications such as VoIP, video telephony, mobile multimedia, interactive gaming and more.

A brief history of 3G First generation wireless, or 1G, refers to analogue networks introduced in the mid-1980s. Examples include advanced mobile phone service (AMPS) used in North America and total access communications system (TACS) used in the UK. In South Africa we had the C450 mobile system run by Telkom which was relatively expensive and took ten years to achieve ten thousand subscribers. Most 1G technologies and systems were country or region-specific and thus offered limited coverage. As mobile communications grew in popularity, networks often became overloaded, resulting in busy signals and dropped calls. The solution was second-generation wireless, or 2G, which emerged in the early 1990s. 2G technologies were digital and offered the much-needed capacity that 1G analogue systems did not afford. Several technologies were widely used:

• GSM was and still is popular in Europe and Asia Pacific, and Latin America

• TDMA was used in the Americas and is still used in Latin America

• CDMA IS-95 or cdma One was used primarily in the Americas and Asia Pacific However, these 2G technologies are incompatible with each other. Thus, mobile service subscribers were still often limited to using their phones in a single country or region. In an effort to standardize future digital wireless communications and make global roaming with a single handset possible, the ITU established a single standard for wireless networks in 1999. Called IMT-2000, which is commonly referred to today as 3G, the initiative set forth the requirements (mentioned above) for the third generation of wireless networks.

 

Where is 3G today in Africa?

 

Today, wideband CDMA (WCDMA) and CDMA2000 are by far the dominant standards in terms of current commercial services, operator deployment plans and vendor support. In the ACF website one may see via the selection of maps available where the deployments in various frequency bands are taking place. Nigeria has 39 licensed operating companies in the CDMA2000 1X-EV-DO 800 MHz band alone. Tanzania has just licensed four. MTN and UTL in Uganda have been operating CDMA2000 WLL systems for a while now. Mauritius and South Africa have had WCDMA networks for more than a year. Movicel in Angola is the largest mobile operator in Africawith CDMA2000. Every one of the 48 countries in sub-Saharan Africa are licensing and deploying CDMA systems in the next year.

 

Launched commercially by wireless operators in 2000, CDMA2000 1X was the world’s first operational 3G technology, capable of transmitting data faster than most dial-up services. Today, more than 210-million people enjoy the benefits of CDMA2000 1X, which provides enhanced data capacity compared with all 2G technologies. A l s o k n o w n a s u n i v e r s a l m o b i l e telecommunications system (UMTS), WCDMA is the 3G standard chosen by most GSM/GPRS wireless network operators wanting to evolve their systems to 3G network technology. WCDMA offers enhanced voice and data capacity and peak data rates faster than most dial-up services and average rates consistently greater than global system for mobile communications/ general packet radio service (GSM/GPRS) and enhanced data for GSM evolution (EDGE). As of February 2006, more than 51-million subscribers were using WCDMA for their mobile voice and data needs.

 

What does 3G offer Africans and who benefits from it?

 

3G wireless services enable consumers and professionals to experience excellent voice quality as well as a wide array of compelling data services, including:

• Mobile internet connectivity

• Mobile e-mail

• Multimedia services, such as digital photos and movies taken by and shared via wireless handsets

• Wireless application downloading

• Video-on-demand and short-format Clip cast content

• Real-time multiplayer gaming

• Enhanced emergency and location-based services

• Low-latency push-to-talk and push-to-videomessage services

For consumers, 3G quite simply means a more rewarding wireless experience –high-quality, low-cost voice, and fun and useful data services whenever they want them, whenever they need them and wherever they have mobile phone service. The small farmer and rural business entrepreneur in Africa can empower himself by linking into the3G networks emanating from his cities.

 

CDMA 2000 systems in 850 MHz have a cell area of 2712 km 2 and in 450 MHz a cell area of 7521 km 2 . The relative range is 29,4 km and 48,9 km respectively. With WCDMA this is severely reduced due to the high frequency with a cell area of only 312 km 2 . In South Africa Vodacom and MTN have only rolled out their WCDMA coverage in very limited urban areas. For them it was an expensive “forklift migration” due to the fact that GSM air interface is totally incompatible with WCDMA. Not so for countries and operators that originally went for CDMA 2000 networks. The systems are forward and backward compatible. So for new operators in Africa the system of choice is CDMA 2000 with a frequency in 850 MHz for its range and the fact that 95% of handsets are manufactured in this band. Lehman Brothers estimates that the total cost of building and operating a CDMA 2000 network to serve a million users at 850 MHz is 31 - 38 % of the cost for the same WCDMA network.

 

In South Africa the second network operator and five of the seven under-serviced area licenses have selected CDMA 2000 1xEV-DO Rev. A in 850 MHz as their technology of choice. See below what the properties of such systems will have for their new users. Enterprises can leverage 3G’s advanced data capabilities to gain critical competitive advantages such as increased productivity, streamlined processes, improved customer service and enhanced communications. Workforces, farmers, transporters and entrepreneurs can essentially work from anywhere at anytime. Phones coming out of China even have built-in barcode scanners. 3G technology also benefits the other participants in the wireless value chain. Wireless network operators are able to capitalize on increased voice capacity, greater network efficiency, lower costs per user served, increased average revenue per user and greater service differentiation. Device manufacturers can leverage the enhanced capabilities of 3G networks to sell premium wireless devices in volume. Finally, 3G technology’s data capabilities open up an enormous world of opportunity for application developers and content providers.

 

What’s next?

 

The future of 3G is impressive - in fact, it’s already here. CDMA2000 1xEV-DO Launched in 2002, CDMA2000 1xEV-DO is a data-optimized evolution of the CDMA2000 standard, capable of delivering peak forward link data rates of 2,4 Mbps, or rates comparable to wired broadband. By dividing radio spectrum into separate voice and data channels, EV-DO, which uses a 1,25 MHz data channel, improves network efficiency and eliminates the chance that an increase in voice traffic would cause data speeds to drop. CDMA2000 1xEV-DO Rev. A EV-DO Rev. A is a significant evolutionary step in the CDMA2000 1xEV-DO progression. Expected to launch in 2006, EV-DO Rev. A provides a peak forward link data rate of 3,1 Mbps and a peak reverse link rate of 1,8 Mbps. In addition, EV-DO Rev. A incorporates comprehensive improvements to the air link that reduce call set up times, decrease transmission delays and enable greater service control. These enhancements, combined with the increased data rates, enable network operators using EV-DO Rev. A to offer richer, more interactive applications and services such as wire line-quality VoIP, low-latency push-to-talk, online gaming, video on demand and video messaging, as well as the ability to upload large data files. EV-DO Rev. A also features Platinum multicast. Offering three times more capacity than Gold multicast, platinum multicast provides even greater network efficiency and reduces the cost of rich media content delivery to a large subscriber base when coupled with a content delivery system solution such as the MediaFLO media distribution system.

 

Platinum multicast’s multi-tone modulation enhancement uses CDMA and OFDM waveforms on the forward link to multimedia handsets, while continuing to use CDMA for forward and reverse links on unicast services. With its additional speed and capacity, Platinum multicast enables operators to deliver live content such as breaking news, traffic, sports and weather. Furthermore, it offers operators greater flexibility depending on network needs, operators can choose to deliver more channels of content or fewer channels of content in higher resolution. EV-DO Rev. B EV-DO Rev. B, a further development on the CDMA2000 roadmap beyond Rev. A, offers multi-channel capabilities, which allow network operators to aggregate multiple 1,25 MHz channels simultaneously and increase data rates dramatically. The first implementation of Rev. B will support up to 9,3 Mbps on the forward link and 5,4 Mbps on the reverse link (the standard, at its theoretical limit and aggregating 20 MHz of spectrum, allows up to 75 Mbps on the forward link and 27 Mbps on the reverse link) One of the chief advantages of Rev. B is that it puts the control for scaling bandwidth into the network operators’ hands, allowing operators to tailor their systems to the spectrum they have available. Rev. B’s flexibility will enable significant capacity and performance improvements, while protecting CDMA2000 operators’ current investments in networks and devices. Furthermore, it will allow more of operators’ spectrum to be used for IP-based services, including mobile broadband data, wire line-quality VoIP and multicast traffic in a manner that results in lower operator costs through greater efficiencies.

 

HSDPA/HSUPA HSDPA (high-speed downlink packet access) is an evolution of WCDMA, optimized for packet-switched data applications. HSDPA provides impressive enhancements over WCDMA on the downlink (also referred to as the forward link) - promising 14,4 Mbps peak data rates – resulting in a better end user experience. Subscribers with HSDPA service are able to receive emails with large attachments, surf the web or download multimedia or text files faster than ever. For operators, HSDPA offers a three- to five-fold capacity increase over WCDMA, which translates into significantly more data users and lower cost per bit. At the conclusion of January 2006, there were more than 50 other HSDPA networks planned or in deployment and nine announced trials around the world. On 3 April 2006, the first HSDPA network was launched in South Africa by Vodacom. HSDPA will be followed by another evolution still in standards development. Just as EV-DO Rev. A greatly improves the uplink of 1xEV-DO, high-speed uplink packet access (HSUPA) extends the benefits of HSDPA to the uplink (also referred to as the reverse link). HSUPA will support up to 5,76 Mbps peak rates, further improving the end user experience. HSUPA will provide end users with a DSL-like experience and enable lower latency services such as voice over IP, multiplayer interactive gaming, push-to-talk and more. The first HSUPA deployments are expected in 2007. Moving forward, both CDMA2000 and WCDMA will continue to evolve with the goal to increase network capacity, improve data rates and enhance system performance. These are impressive systems that will improve the lives of all who live inAfrica.

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Australia's Growing Disaster

Farming is threatening to destroy the soil and native flora and fauna over vast areas of Australia. What price should be put on conservation?

Australia's National Greenhouse Gas Inventory Committee estimates that burning wood from cleared forests accounts for about 30 per cent of Australia's emissions of carbon dioxide, or 156 million tones a year. And water tables are rising beneath cleared land. In the Western Australian wheat belt, estimates suggest that water is rising by up to 1 meter a year. The land is becoming waterlogged and unproductive or is being poisoned by salt, which is brought to the surface. The Australian Conservation Foundation (ACF) reckons that 33 million hectares has been degraded by salivation. The federal government estimates the loss in production from salinity at A$200 million a year.

 

According to Jason Alexandra of the ACF, this list of woes is evidence that Australia is depleting its resources by trading agricultural commodities for manufactured imports. In effect, it sells topsoil for technologies that will be worn out or redundant in a few years. The country needs to get away from the "colonial mentality" of exploiting resources and adopt agricultural practices suited to Australian conditions, he says.

 

Robert Hadler of the National Farmers' Federation (NFF) does not deny that there is a problem, but says that it is "illogical" to blame farmers. Until the early 1980s, farmers were given tax incentives to clear land because that was what people wanted. If farmers are given tax breaks to manage the land sustainable, they will do so. Hadler argues that the two reports on land clearance do not say anything which was not known before.

 

Australia is still better off than many other developed countries, says Dean Graetz, an ecologist at the CSIRO, the national research organization. "A lot of the country is still notionally pristine," he says. "It is not transformed like Europe where almost nothing that is left is natural." Graetz, who analyzed the satellite photographs for the second land clearance report, argues that there is now better co-operation between Australian scientists, government officials and farmers than in the past.

 

But the vulnerable state of the land is now widely understood, and across Australia, schemes have started for promoting environment friendly farming. In 1989, Prime Minister Bob Hawke set up Landcare, a network of more than 2000 regional conservation groups. About 30 percent of landholders are members, "It has become a very significant social movement," says Helen Alexander from the National Landcare Council. "We started out worrying about not much more than erosion and the replanting of trees but it has grown much more diverse and sophisticated,"

 

But the bugbear of all these conservation efforts is money. Landcare's budget is A$110 million a year, of which only A$6 million goes to farmers. Neil Clark, an agricultural consultant from Bendigo inVictoria, says that farmers are not getting enough. "Farmers may want to make more efficient use of water and nutrients and embrace more sustainable practices, but it all costs money and they just don't have the spare funds," he says.

 

Clark also says scientists are taking too large a share of the money for conservation. Many problems posed by agriculture to the environment have been "researched to death", he says. "We need to divert the money for a while into getting the solutions into place." Australia's chief scientist, Michael Pitman, disagrees. He says that science is increasingly important. Meteorologists, for example, are becoming confident about predicting events which cause droughts in Australia. "If this can be done with accuracy then it will have immense impact on stocking levels and how much feed to provide," says Pitman, 'The end result will be much greater efficiency."

 

Steve Morton of the CSIRO Division of Wildlife and Ecology says the real challenge facing conservationists is to convince the 85 per cent of Australians who live in cities that they must foot a large part of the bill. "The land is being used to feed the majority and to produce wealth that circulates through the financial markets of the cities," he says. One way would be to offer incentives to extend the idea of stewardship to areas outside the rangelands, so that more land could be protected rather than exploited. Alexander agrees. "The nation will have to debate to what extent it is willing to support rural communities," she says. "It will have to decide to what extent it wants food prices to reflect the true cost of production. That includes the cost of looking after the environment."

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Books, Films and Plays

The novelist's medium is the written word, one might almost say the printed word; the novel as we know it was born with the invention of printing. Typically, the novel is consumed by a silent, solitary reader, who may be anywhere at the time. The paperback novel is still the cheapest, most portable and adaptable form of narrative entertainment. It is limited to a single channel of information -writing. But within that restriction it is the most versatile of narrative forms. The narrative can go, effortlessly, anywhere: into space, people’s heads, palaces, prisons and pyramids, without any consideration of cost or practical feasibility. In determining the shape and content of his narrative, the writer of prose fiction is constrained by nothing except purely artistic criteria.

This does not necessarily make his task any easier than that of the writer of plays and screenplays, who must always be conscious of practical constraints such as budgets, performance time, casting requirements, and so on. The very infinity of choice enjoyed by the novelist is a source of anxiety and difficulty. But the novelist does retain absolute control over his text until it is published and received by the audience. He may be advised by his editor to revise his text, but if the writer refused to meet this condition no one would be surprised. It is not unknown for a well established novelist to deliver his or her manuscript and expect the publisher to print it exactly as written. However, not even the most well established playwright or screenplay writer would submit a script and expect it to be performed without any rewriting. This is because plays and motion pictures are collaborative forms of narrative, using more than one channel of communication.

 

The production of a stage play involves, as well as the words of the author, the physical presence of the actors, their voices and gestures as orchestrated by the director, spectacle in the form of lighting and "the set”, and possibly music. In film, the element of spectacle is more prominent in the sequence of visual images, heightened by various devices of perspective and focus. In film too, music tenets to be more pervasive and potent than in straight drama. So, although the script is the essential basis of both stage play and film, it is a basis for subsequent revision negotiated between the writer and the other creative people involved; in the case of the screenplay, the writer may have little or no control over the final form of his work. Contracts for the production of plays protect the rights of authors in this respect. They are given "approval” of the choice of director and actors and have the right to attend rehearsals. Often a good deal of rewriting takes place in the rehearsal period and sometimes there is an opportunity for more rewriting during previews before the official opening night.

 

In film or television work, on the other hand, the screenplay writer usually has no contractual right to this degree of consultation. Practice in t his respect varies very much from one production company to another, and according to the nature of the project and the individuals involved. In short, while the script is going through its various drafts, the writer is in the driver's seat, albeit receiving advice and criticism from the producer and the director. But once the production is under way, artistic control over the project tends to pass to the director. This is a fact overlooked by most journalistic critics of television drama, who tend (unlike film critics) to give all the credit or blame for success or failure of a production to the writer and actors, ignoring the contribution, for good or ill, of the director.

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Astonishing The Gods

Astonishing the Gods by Ben Okri is not for the habitually cynical. Nor, even if you're not a habitual cynic, is it the kind of book that should be read on a day when the real world is likely to intrude. This book oozes escapism. But it isn't easy or simple to digest.

So, to avoid irritation, do not try

 to read this short but intense novel on your way to work or at times when you might have to stop to answer telephone calls or cope with domestic or other practicalities. Also, avoid it like the plague if you are hooked on straightforward linear narratives or if you're the sort of person who can only identify with trees that are trees and buildings that don't dissolve into thin air.

 

Apologies for appearing to labor this point about who should read Okri and about when and how he should be read. But he has been so harshly criticized by the impatiently earthbound that the point cannot be made strongly enough. If you aren't capable of -or in the mood for - locking yourself away for a few hours and allowing your mind to drift in a dreamlike state down magical, mythical avenues, you’d be best to settle for a book with a 'normal’ plot, tangible landscapes and effortlessly understandable characters.

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Visit to Student Fair is Vital Homework

A

The number and variety of courses on offer these days makes it difficult to pick the right one. But thousands of Europeans who flock to Brussels Exhibition Centre will be shown how to simplify the difficult job of choosing the right course of study for the career they wish to pursue.

В

Ten years ago a handful of Belgian teenagers, baffled by the array and number of university courses offer, put their heads together to try to hack their way through the academic undergrowth. They knew that choosing the wrong subject or failing to make the grade would make finding a job all the more difficult. They decided something had to be done to help students approach the task of choosing a course in an effective way. They came up with the idea of a Student Fair,

 

С

It was decided that this would take the form of a small forum for everyone in Belgium involved in higher education from both the French and Dutch-speaking parts of the country. It would provide the opportunity for representatives of educational institutions to give information on the courses they have on offer and allow school-leavers time to discuss these with them.

 

D

But what the youngsters did not know was that they were tapping a source of anxiety among students right across Europe. The fair became an annual event. It expanded to include higher education bodies from the whole continent, becoming known as the European Student Fair.

 

E

Each year ten million students are faced with the same dilemma/said exhibition organizer Valerie de Narrate bewildering variety of options, the evolution of the employment market, the economic downturn, changes in working methods and personal interests all play an important role in the decision-making process. We hope the fair can help people make the correct decision for them.'

 

F

This year the theme of the fair is 'the right to education for all’ and to mark this there is a special exhibition area for bodies that promote equal opportunities in education. Also, the Master of Business Administration course continues to attract an enormous amount of interest across Europe and, in response to demand, air organizers are once again holding an MBA day.

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The Writing Module

GENERAL WRITING STRATEGIES

 

As a student at college or university, you will have to produce a lot of written material. Some of this may be in the form of short essays or reports. Other pieces of writing will be longer and will require considerable planning and attention to detail. It will therefore be important for you to be able to express yourself clearly, write in a variety of styles and organize your ideas carefully. You will also need to be fairly accurate in your writing, so that your message is not obscured by a lot of grammatical errors.

IELTS WRITING (ACADEMIC)

 

IELTS tests your ability to produce two quite different pieces of writing in a fairly short period of time. The test is divided into two parts and you are allowed one hour to complete both parts.

 

Writing Task 1

 

In the first part, you are given a task based on some graphic or pictorial information. You are expected to write a descriptive report of at least 150 words on the information provided,

 

Writing Task 2

 

The second task is more demanding. You are expected to produce a written argument on a given topic and to organize your answer clearly, giving some examples to support your points. You will have to write at least 250 words and, as Task 2 is longer than Task 1, you are advised to spend approximately 40 minutes on this task and 20 minutes on the first task.

 

IELTS WRITING (GENERAL TRAINING)

 

If you are planning to take the GT module, the Writing test is different. You are allowed one hour to complete two tasks, of 150 and 250 words, as in the Academic module. However, Task 1 is always a letter, while Task 2 is an essay based on a given topic.

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How Blogs Work

Blogs appear on the news pretty often these days. For example, a reporter is tipped to a story by a blog, or a blog reports another angle on a story. Blogs show up in magazines a lot, too.

But there is a good chance you have never seen a blog (also known as a weblogs) or experienced the blogosphere. What are blogs? There are now millions of them -- where did they all come from?

One of the things that is so amazing about blogs is their simplicity.

Think about a "normal Web site." It usually has a home page, with links to lots of sub-pages that have more detail. HowStuffWorks is like this, with thousands of information pages all organized under a home page. A small business site follows the same format -- it might have a home pag e and five or 10 sub-pages. Most traditional Web sites follow this format. If the site is small, it is sort of like an online brochure. If it is large, it is like an electronic encyclopedia.

A typical Web site has a home page that links to sub-pages within the site. CNN.com is typical of this genre. The CNN site contains thousands of articles all organized into big categories. The categories and all the latest stories are accessed from the home page.

A blog is much simpler:

A blog is normally a single page of entries. There may be archives of older entries, but the "main page" of a blog is all anyone really cares about.

A blog is organized in reverse-chronological order, from most recent entry to least recent.

A blog is normally public -- the whole world can see it.

The entries in a blog usually come from a single author.

The entries in a blog are usually stream-of-consciousness. There is no particular order to them. For example, if I see a good link, I can throw it in my blog. The tools that most bloggers use make it incredibly easy to add entries to a blog any time they feel like it.

In this article, you will have a chance to enter the world of blogging. You will even learn how to create your own blog and publish it to the world.

A typical blog has a main page and nothing else. On the main page, there is a set of entries. Each entry is a little text blurb that may contain embedded links out to other sites, news stories, etc. When the author adds a new entry, it goes at the top, pushing all the older entries down. This blog also has a right sidebar that contains additional permanent links to other sites and stories. The author might update the sidebar weekly or monthly.

Basically, a blog is a lot like anonline journal or diary. The author can talk about anything and everything. Many blogs are full of interesting links that the author has found. Blogs often contain stories or little snippets of information that are interesting to the author.

Even though blogs can be completely free-form, many blogs have a focus. For example, if a blogger is interested in technology, the blogger might go to the Consumer Electronics Show and post entries of the things he/she sees there. If a blogger is interested in a certain disease, he/she might post every news article and every piece of research he/she finds on the disease. If a blogger is interested in economic issues, he/she might post links to articles that discuss the economy and then offer commentary on them.

There are people who use their blogs simply as a scrapbook -- a form of online memory. Whenever the author finds a link or a snippet of information that he/she wants to remember, it gets posted in the blog. Even if no one else ever looks at it, it is still useful to the author because the blog is a searchable electronic medium that the author can access with a Web browser anywhere in the world.

In other words, a blog can be anything the author wants it to be. The thing that all blogs have in common is the reverse-chronological ordering of entries.

The Blogosphere

One thing about blogs that is so fascinating is the interlinking. There are millions of people keeping active blogs, and bloggers often tend to look at other people's blogs. When they see something they like in their favorite blogs, bloggers will often link to and comment on it.

All of this tight interlinking has created a phenomenon known as the blogosphere. The blogosphere consists of all the cross-linked blogs. Once you arrive at one blog in the blogosphere, it will often have links that connect you to many of the other sites in the blogosphere. You can bounce around in the blogosphere for years if you like that sort of thing.

Many blog readers enter the blogosphere and find one (or a few) bloggers they really like. For example, you might have a blog you use to keep up to date on the latest technology, and another to keep up to date on the latest news. The blogger is acting a lot like a DJ on a radio show, choosing stories, links and/or snippets just like the DJ chooses songs. People who like what the blogger focuses on each day come back and read that blogger every day or so. Celebrities have also gotten into the act, creating blogs as a way to interact with their fans.

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Penguins show signs of stress

A new argument has been put forward as to whether penguins

are disturbed by the presence of tourists in Antarctica.

Previous research by scientists from Keil University in Germany monitored Adelie penguins and noted that the birds' heart rates increased dramatically at the sight of a human as far as 30 meters away. But new research using an artificial egg, which is equipped to measure heart rates, disputes this. Scientists from the Scott Polar Research Institute at Cambridge say that a slow moving human who does not approach the nest too closely, is not perceived as a threat by penguins.

 

The earlier findings have been used to partly explain the 20 per cent drop in populations of certain types of penguins near tourist sites. However, tour operators have continued to insist that their activities do not adversely affect wildlife in Antarctica, saying they encourage non-disruptive behavior in tourists, and that the decline in penguin numbers is caused by other factors,

 

Amanda Nimon of the Scott Polar Research Institute spent three southern hemisphere summers at Cuverville Island in Antarctica studying penguin behavior towards humans. "A nesting penguin will react very differently to a person rapidly and closely approaching the nest," says Nimon. "First they exhibit large and prolonged heart rate changes and then they often flee the nest leaving it open for predators to fly in and remove eggs or chicks." The artificial egg, specially developed for the project, monitored both the parent who had been 'disturbed' when the egg was placed in the nest and the other parent as they both took it in turns to guard the nest.

 

However, Boris Culik, who monitored the Adelie penguins, believes that Nimon's findings do not invalidate his own research. He points out that species behave differently - and Nimon's work was with Gentoo penguins, Nimon and her colleagues believe that Cultk's research was methodologically flawed because the monitoring of penguins' responses entailed capturing and restraining the birds and fitting them with heart-rate transmitters. Therefore, argues Nimon, it would not be surprising if they became stressed on seeing a human subsequently.

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Prehistoric insects spawn new drugs

by Steve Connor, Science Correspondent 

 

A

Insects entombed in fossilized amber for tens of millions of years have provided the key to creating a new generation of antibiotic drugs that could wage war on modern diseases. Scientists have isolated the antibiotics from microbes found either inside the intestines of the amber-encased insects or in soil particles trapped with them when they were caught by sticky tree resin up to 130 million years ago. Spores of the microbes have survived an unprecedented period of suspended animation, enabling scientists to revive them in the laboratory.

 

B

Research over the past two years has uncovered at least four antibiotics from the microbes and one has been able to kill modern drug resistant bacteria that can cause potentially deadly diseases in humans. Present-day antibiotics have nearly all been isolated from micro-organisms that use them as a form of defense against their predators or competitors. But since the introduction of antibiotics into medicine 50 years ago, an alarming number have become ineffective because many bacteria have developed resistance to the drugs. The antibiotics that were in use millions of years ago may prove more deadly against drug-resistant modem strains of disease-causing bacteria.

 

C

Raul Cano, who has pioneered the research at the California Polytechnic State University at San Luis Obispo, said the ancient antibiotics had been successful in fighting drug-resistant strains of staphylococcus bacteria, a "super bug" that has threatened the health of patients in hospitals throughout the world. He now intends to establish whether the antibiotics might have harmful side effects.” The problem is how toxic it is to other cells and how easy it is to purify," said. Cano.

 

D

A biotechnology company, Amber gene has been set up to develop the antibiotics into drugs. If any ancient microbes are revived that resemble present-day diseases, they will be destroyed in case they escape and cause new epidemics. Drug companies will be anxious to study the chemical structures of the prehistoric antibiotics to see bow they differ from modern drugs. They hope that one ancient antibiotic molecule could be used as a basis to synthesize a range of drugs.

 

E

There have been several attempts to extract material such as DNA from fossilized life-forms ranging from Egyptian mummies to dinosaurs but many were subsequently shown to be contaminated. Cano’s findings have been hailed as a break-through by scientists, Edward Goldenberg, an expert on extracting DNA from fossilized life-forms at Wayne State University in Detroit, said: "They appear to be verifiable, ancient spores. They do seem to be real.” Richard Lenski, professor of microbial ecology at Michigan State University, said the fight against antibiotic-resistant strains of bacteria, such as tuberculosis and staphylococcus, could be helped by the discovery.

 

F

However, even the discovery of ancient antibiotics may not halt the rise of drug-resistant bacteria. Stuart Levy, a micro-biologist at Tufts University in Boston, warned that the bacteria would eventually evolve to fight back against the new drags.” There might also be an enzyme already out there that can degrade it. So the only way to keep the life of that antibiotic going is to use it sensibly and not excessively,” he said.

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AUSTRALIA'S FIRST COMMERCIAL WIND FARM

It's two years since the rotor blades began spinning in Esperance,

Western Australia

A

HARVEST time in Esperance is constant. As long as the wind blows - which is pretty much all the time –nine identical synchronized wind turbines reap the benefits of the dependable winds that gust up around the southern coastline of Western Australia. These sleek ,white, robot-like wind turbines loom up on the horizon forming part of Australia's first commercial wind farm. They're not only functional machines that help provide electricity for this secluded coastal town, but increasingly, they're also draw cards for curious tourists and scientists alike.

 

B

Because of its isolation, Esperance is not linked to Western Power's grid which supplies electricity from gas-, coal-and oil-fired power stations to the widespread population of Western Australia. Before the wind turbines went in, Esperance's entire electricity needs were met by the diesel power station in town.

 

C

The $5.8 million Ten Mile Lagoon project is not Esperance's first wind farm. The success of a smaller, experimental wind farm, at a spot called Salmon Beach, encouraged the State's power utility to take Esperance wind seriously. Today the wind turbines at Ten Mile Lagoon work in conjunction with the diesel power station, significantly reducing the amount of the town's electricity generated by expensive diesel power.

 

D

The wind farm is connected to the power station by a 33-kilovolt power line, and a radio link between the two allows operators to monitor and control each wind turbine. The nine 225-kilowatt Vestas wind turbines produce a total generating capacity of two megawatts and provide around 12 per cent of the energy requirements of Esperance and its surrounding districts.

 

E

The power produced by a wind turbine depends on the size and efficiency of the machine and, of course, on the energy in the wind. The energy in the wind available to the wind turbines is proportional to wind speed cubed. Thus, the greater the wind speed, the greater the output of the turbine. In order to achieve optimum wind speeds, the right location is imperative.” You have to accept the nature of the beast," Mr. Rosser, Western Power's physicist said.” As surface dwellers our perceptions of wind speeds are bad. As you go higher, wind speed increases significantly."

 

F

The most favorable wind sites are on gently sloping hills, away from obstructions like trees and buildings and where the prevailing winds are not blocked. Computer modeling was used to select the best site for Esperance's wind farm. Scientists were concerned not only with efficiency, but also with protecting the coastal health environment which is rich in plant life and home to tiny pygmy and honey possums, and a host of bird species. In addition, the wind farm is adjacent to Esperance's popular scenic tourist drive.

 

G

Strict erosion controls have been implemented and access to the wind farm is limited to selected viewing areas. The wind turbine towers are painted white and devoid of corporate logos or signage. According to Mr. Rosser there is something of a worldwide backlash against wind farms with regard to their visual impact,” But because wind turbines perform best in the most exposed positions, they will always be visible. There is a very real need to balance environmental and technical requirements. I think the Ten Mile Lagoon Wind Farm sets the standards for environmentally friendly developments."

 

H

In fact, the project has become something of a tourist attraction in itself, Esperance shire president Ian Mickel said the wind turbines had been well accepted by locals.” We have watched the wind farm develop with great interest, and now we find visitors to Esperance are equally enthusiastic about it," he said. The aim now is to identify other remote locations where wind turbines will be a feasible means of supplementing existing power stations.

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Succeeding in title role

Magazine circulations are in the millions and advertising

revenue is rising despite the growth of TV and electronic

media, reports David Short

A
Print is not dead yet -at least not when it comes to magazines. Despite ever- growing competition from television and electronic media, a new report shows that worldwide advertising expenditure in consumer magazines has doubled over the past decade.

В
The report also shows that many magazines in Europe continue to enjoy circulations in the millions, despite the ever-growing number of television channels, whether cable, satellite, terrestrial, analogue, or digital, and the incursion of the Internet. And new French research has revealed that magazines are still powerful tools for owners of brands.

С
Advertising expenditure worldwide was $225 billion last year, according to the report World Magazine Trends.$32 billion of this, or 14%,was taken by magazines. In Europe, the share of consumer magazine advertising expenditure was $12 billion or 21%of an estimated overall spend of $57 billion. But the share has dropped in the past 15 years from 30 per cent, with decline having been particularly severe in Belgium and Germany where commercial television was introduced relatively late.

D
However, the types of magazines which Europeans choose to flip through still varies dramatically according to country, with few signs that the European magazine with a common title is making inroads across nations. Interests which can create top-
selling titles in one country are nowhere to be seen in the circulation lists of others.

E
But whatever their relative importance across Europe, magazines have one real advantage over broadcast media. For advertisers such as tobacco and alcohol producers, which are barred or severely restricted on television in some countries, magazines remain a safe haven for their messages. Read More......

' Salty' rice plant boosts harvests

British scientists are breeding a new generation of rice plants that will be able to grow in soil contaminated with salt water. Their work may enable abandoned farms to become productive once more, writes Sean Margrave.

 

more, writes Sean Margrave. Tim Flowers and Tony Yeo, from Sussex University's School of Biological Sciences, have spent several years researching how crops, such as rice, could be made to grow in water that has become salty.

 

The pair have recently begun a three-year program, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive saline conditions. The aim is to breed this capability into crops, starting with rice.

 

It is estimated that each year more than 10m hectares of agricultural land are lost because salt gets into the soil and stunts plants. The problem is caused by several factors. In the tropics, mangroves that create swamps and traditionally form barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep in. In Latin America, irrigation often causes problems when water is evaporated by the heat, leaving salt deposits behind.

 

Excess salt then enters me plants and prevents them functioning normally, Heavy concentrations of minerals in the plants curb the process of osmosis and stop them drawing up the water they need to survive.

 

To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plant's growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests until the resulting seeds are ready to be considered for commercial use.

 

Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manner of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world.

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GOING DIGITAL

Electronic libraries will make today's Internet

pale by comparison. But building them will

not be easy.

All over the world, libraries have begun the Herculean task of making faithful digital copies of the books, images and recordings that preserve the intellectual effort of humankind. For armchair scholars, the work promises to bring such a wealth of information to the desktop that the present Internet may seem amateurish in retrospect....

Librarians see three clear benefits to going digital. First, it helps them preserve rare and fragile objects without denying access to those who wish to study them. The British Library, for example, holds the only medieval manuscript of Beowulf in London. Only qualified scholars were allowed to see it until Kevin S.Kiernan of the University of Kentucky scanned the manuscript with three different light sources (revealing details not normally apparent to the naked eye)and put the images up on the Internet for anyone to peruse. Tokyo's National Diet Library is similarly creating highly detailed digital photographs of 1,236 woodblock prints, scrolls and other materials it considers national treasures so mat researchers can scrutinize them without handling the originals.

A second benefit is convenience. Once books are converted to digital form, patrons can retrieve them in seconds rather than minutes. Several people can simultaneously read the same book or view the same picture. Clerks are spared the chore of re shelving. And libraries could conceivably use the Internet to lend their virtual collections to those who are unable to visit in person.

The third advantage of electronic copies is that they occupy millimeters of space on a magnetic disk rather man meters on a shelf. Expanding library buildings is increasingly costly. The University of California at Berkeley recently spent $46 million on an underground addition to house 1.5 million books -an average cost of $30 per volume. The price of disk storage, in contrast, has fallen to about $2 per 300-page publication and continues to drop.

From "Going Digital” by Michael Lesk, Copyright © March 1997 by Scientific American, Inc. All rights reserved. Read More......

Baby Love

Why we want to take

care of teddy bears

At the turn of the century, the first teddy bears had low foreheads, long snouts and long limbs like real bears. But over time, they have developed more baby like features.

 

A group of scientists was curious to know whether teddies evolved this way because children demand baby faced bears or because adults did. They gathered together eight pairs of teddies, each comprising a baby faced bear and an adult featured one. These teddies were shown to children aged four, six and eight years old,

 

When asked to choose their favorite bear from each pair, the older children (43 out of 54) preferred the baby faced teddies. But the four year olds chose the baby faced and adult featured bears of each pair equally. When asked which one of all the bears they liked best, the older children chose more baby-faced bears but the four year olds preferred ones with adult-features.

 

The scientists also asked the children what they would like to do with their favorite bear. The four-year-olds wanted to play with it, but the older children said they would like to sleep with the bear. The scientists suggest that young children do not develop a specific desire to look after the young and helpless until they are older.

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Divers hunt for ruins of Pharos lighthouse

Underwater archaeologists

search the waters for Egyptian

relics, Christopher Walker writes

 

A team of 30 divers is hurriedly searching the Mediterranean for the remains of the mighty Pharos lighthouse, built more than 2,200 years ago and regarded as one of the Seven Wonders of the ancient world.

 

In addition to Pharos, the joint French and Egyptian expedition is searching for the remnants of Greek temples and statues. The aim of the £300,000 project is to map a 23,920 sq yard area off Egypt's second largest city, founded by Alexander the Great. Under the water is a vast collection of ruins, some of which the 20 French and ten Egyptian divers hope to excavate and salvage. The team is hoping that among the remnants may be the lighthouse, built in 279 BC during the reign of Ptolemy II.

 

The huge white marble building was the marvel of its day. It was more than 400ft high in a colonnaded court and was equipped with a hydraulic lift to raise fuel to the roof. Its lantern, probably magnified by a reflecting device, could be seen over a radius of 34 miles. Within its square base were up to 300 rooms designed to house mechanics and operators; above were an octagonal storey and a circular storey, topped by a lantern with a beacon, the exact workings of which are still a mystery.

 

Although the lantern collapsed as early as the eighth century, the lighthouse served for 1,400 years as the symbol of Alexandria and a beacon for ships, until devastating earthquakes in 1100 and 1307 brought it tumbling down, presumably sending much of the debris into the sea surrounding Pharos island on which it was built.

 

The divers have made some fascinating discoveries, including at least three layers of blocks, some estimated to be as heavy as 70 tones, which may have been part of the lighthouse. "It is certainly possible that some of the pieces come from the lighthouse itself," said Jean-Pierre Cortegiani, a member of the expedition. "In fact, it would be amazing if nothing came from the lighthouse, seeing as this is where it toppled into the sea." Also discovered were hundreds of smaller blocks, thought to be pieces of temples and statues dating back to the Ptolemaic period. Among them were pieces of ancient columns, many inscribed, and huge granite and marble statues of sphinxes and Egyptian Gods, some of which stood 15ft high.

 

"We are making an identification of the blocks, studying the inscriptions and choosing some to be taken out," Cortegiani said. "We cannot take all the blocks out, but maybe we can have something like an underwater archaeological park." Read More......

Sifting through the Sands of Time

When you're on the beach, you're stepping on ancient mountains, skeletons of marine animals, even tiny diamonds. Sand provides a mineral treasure-trove, a record of geology's earth-changing processes.

 

Sand: as children we play on it and as adults we relax on it. It is something we complain about when ft gets in our food, and praise when it's moulded into castles. But we don't often look at it, If we did, we would discover an account of a geological past and a history of marine life that goes back thousands and in some cases millions of years.

 

Sand covers not just sea-shores, but also ocean beds, deserts and mountains. It is one of the most common substances on earth, And it is a major element in man made materials too –concrete is largely sand, while glass is made of little else.

 

What exactly is sand? Well, it is larger than fine dust and smaller than shingle. In fact, according to the most generally accepted scheme of measurement, devised by the Massachusetts Institute of Technology, grains qualify if their diameter is greater than 0.06 of a millimeter and less than 0.6 of a millimeter.

 

Depending on its age and origin, a particular sand can consist of tiny pebbles or porous granules. Its grains may have the shape of stars or spirals, their edges lagged or smooth. They have come from the erosion of rocks, or from the skeletons of marine organisms, which accumulate on the bottom of the oceans, or even from volcanic eruptions.

 

Color is another clue to sand's origins. If it is a dazzling white, its grains may be derived from nearby coral outcrops, from crystalline quartz rocks or from gypsum, like the white sands of New Mexico. On Pacific Islands jet black sands form from volcanic minerals. Other black beaches are magnetic. Some sand is very recent indeed, as is the case on the island of Kaomagma in Hawaii, where a beach was created after a volcanic eruption in 1990, Motten lava spilled into the sea and exploded in glassy droplets.

 

Usually, the older the granules, the finer they are and the smoother their edges. The fine, white beaches of northern Scotland, for instance, are recycled from sandstone several hundred million years old. Perhaps they will be stone once more, in another few hundred million.

 

Sand is an irreplaceable industrial ingredient whose uses are legion: but ft has one vital function you might never even notice. Sand cushions our land from the sea's impact, and geologists say it often does a better job of protecting our shores than the most advanced coastal technology. Read More......