Cleaning up a spill 
                                                       Written by Laura Hill

Water and oil don’t mix. We see this every day; just try washing olive oil off your hands without soap or washing your face in the morning with only water. It just doesn’t work!
When an oil spill occurs in the ocean, like the catastrophe in the Gulf of Mexico, what do scientists do to clean up the toxic mess? There are a number of options for an oil spill cleanup and most efforts use a combination of many techniques. The fact that oil and water don’t mix is a blessing and a curse. If oil mixed with water, it would be difficult to divide the two.
Crude oil is less dense than water; it spreads out to make a very thin layer (about one millimetre thick) that floats on top of the water. This is good because we can tell what is water and what is oil. It is also bad, because it means the oil can spread really quickly and cover a very large area, which becomes difficult to manage. Combined with wind, ocean currents and waves, oil spill cleanup starts to get really tricky.
Chemical dispersants can be used to break up big oil slicks into small oil droplets. They work like soaps by emulsifying the hydrophobic (waterrepelling) oil in the water. These small droplets can degrade in the ecosystem quicker than the big oil slick. But unfortunately, this means that marine life of all sizes ingest these toxic, broken-down particles and chemicals.
If the oil is thick enough, it could be set fire, a process called “in situ burning”. Because the oil is highly flammable and floats on top of the water, it is very easy to set it alight. It’s not environmentallyfriendly though; the combustion of oil releases thick smoke that contains greenhouse gases and other dangerous air pollutants.
Some techniques can contain and recapture spilled oil without changing its chemical composition. Booms float on top of the water and act as barriers to the movement of oil. Once the oil is controlled, it can be gathered using sorbents. “Sorbent” is a fancy word for sponge. These sponges absorb the oil and allow it to be collected by siphoning it off the water.
However, weather and sea conditions can prevent and obstruct the use of booms, sorbents and in situ burning. Imagine trying to perform these operations on the open sea with wind, waves and water currents moving the oil (and your boat!) around on the water.
What about the plants and animals? It’s easy to forget about the organisms in the sea that are under water. Out of sight, out of mind! There is not much we can do to help them. But when oil reaches the shore it impacts sensitive coastal environments including the many fish, bird, amphibian, reptilian, and crustaceanspecies that live there. We have easy access to these areas and there are some things we can do to clean up. For the plants, it is often a matter of setting them on fire, or leaving them to degrade the oil naturally. Sometimes, we can spray the oil with nutrients (phosphorus and nitrogen) that can encourage the growth of specialized microorganisms. For species that can tolerate our soaps, manpower is needed to wash every affected animal. Yet, if the animal has tried to lick itself clean, it can die from ingesting the toxic oil.
Unfortunately, there can be many negative economic and social impacts, in addition to the environmental impacts of oil spills and, as you’ve just read, the clean up techniques are far from perfect. Prevention is the very best cleanup technique we have. http://www.curiocity.ca/everyday-science/environme... -cleaning-up-a-spill.html, retrieved on Dec 10, 2010

                                                 Computer Systems Analysts
Nearly all organizations rely on computer and information technology (IT) to conduct business and operate efficiently. Computer systems analysts use IT tools to help enterprises of all sizes achieve their goals. They may design and develop new computer systems by choosing and configuring hardware and software, or they may devise ways to apply existing systems resources to additional 5 tasks. Training requirements for computer systems analysts vary depending on the job, but many employers, when hiring computer systems analysts, usually prefer applicants who have a bachelor's degree. Relevant work experience also is very important. Advancement opportunities are good for those with the necessary skills and experience. For more technically complex jobs, people with graduate 10 degrees are preferred. For jobs in a technical or scientific environment, employers often seek applicants who have at least a bachelor's degree in a technical field, such as computer science, information science, applied mathematics, engineering, or the physical sciences. For jobs in a business environment, employers often seek applicants with at least a bachelor" degree in a business-related field such as management information systems (MIS). Increasingly, employers are seeking individuals 15 who have a master's degree in business administration (MBA) with a concentration in information systems. Despite the preference for technical degrees, however, people who have degrees in other areas may find employment as systems analysts if they also have technical skills. Courses in computer science or related subjects combined with practical experience can qualify people for some jobs in the 20 occupation. Employers generally look for people with expertise relevant to the job. For example, systems analysts who wish to work for a bank may need some expertise in finance, and systems analysts who wish to work for a hospital may need some knowledge of health management. Furthermore, business enterprises generally prefer individuals with information technology, business, and accounting skills and 25 frequently assist employees in obtaining these skills. Technological advances come so rapidly in the computer field that continuous study is necessary to remain competitive. Employers, hardware and software vendors, colleges and universities, and private training institutions offer continuing education to help workers attain the latest skills. Additional training may come from professional development seminars offered by professional 30 computing societies. COMPUTER Systems Analysts. Disponível em: . Acesso em: 5 jan. 2011. Adaptado. 

Model copes with chaos to deliver relief Computer program helps responders transport supplies in tough conditions
By Rachel Ehrenberg Science News, Web edition: Monday, February 21st, 2011
WASHINGTON — Getting blood or other perishable supplies to an area that’s been struck by an earthquake or hurricane isn’t as simple as asking what brown can do for you. But a new model quickly determines the best routes and means for delivering humanitarian aid, even in situations where bridges are out or airport tarmacs are clogged with planes.
The research, presented February 18 at the annual meeting of the American Association for the Advancement of Science, could help get supplies to areas which have experienced natural disasters or help prepare for efficient distribution of vaccines when the flu hits.
Efficient supply chains have long been a goal of manufacturers, but transport in fragile networks — where supply, demand and delivery routes may be in extremely rapid flux — requires a different approach, said Anna Nagurney of the University of Massachusetts Amherst, who presented the new work. Rather than considering the shortest path from one place to another to maximize profit, her system aims for the cleanest path at minimum cost, while capturing factors such as the perishability of the product and the uncertainty of supply routes. ‘You don’t know where demand is, so it’s tricky,’ said Nagurney. ‘It’s a multicriteria decision-making problem.’
By calculating the total cost associated with each link in a network, accounting for congestion and incorporating penalties for time and products that are lost, the computer model calculates the best supply chain in situations where standard routes may be disrupted.
‘Mathematical tools are essential to develop formal means to predict, and to respond to, such critical perturbations,’ said Iain Couzin of Princeton University, who uses similar computational tools to study collective animal behavior. ‘This is particularly important where response must be rapid and effective, such as during disaster scenarios … or during epidemics or breaches of national security.
’ The work can be applied to immediate, pressing situations, such as getting blood, food or medication to a disaster site, or to longer-term problems such as determining the best locations for manufacturing flu vaccines. . Retrieved April 7th, 2011.

'CityVille' now bigger on Facebook than 'FarmVille'
(Mashable) -- Facebook game developer Zynga has proved once
again that it knows exactly what it needs to do to keep millions of
Facebook users happy and occupied.
In less than a month, its latest game "CityVille"___ ______
(become) the most popular application on Facebook, surpassing
Zynga's previous hit "FarmVille" in all areas.
According to AppData, "CityVille" now has 16.8 million daily
active users, compared to "FarmVille's" 16.4 million. Looking at
monthly active users, "CityVille" is also ahead with 61.7 million
users, while "FarmVille" trails behind with 56.8 million users.
Zynga's "FrontierVille" and "Texas HoldEm Poker" also round out
the top five: put those four apps together (we'll disregard the fact
that many of those users overlap for a second) and you have a
very impressive number: 184 million active users across four
games.
The only non-Zynga app in the top five list is "Phrases," _____ at
one point threatened to take the top place, but is now
overshadowed by both "CityVille" and "FarmVille."
"CityVille's" future success wasn't hard to predict after an
amazingly good start at the beginning of December, but it's still
impressive to see Zynga amassing tens of millions of users in a
matter of days, proving that all that venture capital that went into
the company isn't there by accident.
Fonte :cnn.com

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Is Windows 7 Worth It?
Harry McCracken, PC World
Monday, October 19, 2009 10:00 AM PDT

          Reading about a new operating system can tell you only  so much about it: After all, Windows Vista had far more features  than XP, [CONJUNCTION] fell far short of it in the eyes of many  users. To judge an OS accurately, you have to live with it. Over  the past ten months, I've spent a substantial percentage of my  computing life in Windows 7, starting with a preliminary version  and culminating in recent weeks with the final Release to  Manufacturing edition. I've run it on systems ranging from an  underpowered Asus EeePC 1000HE netbook to a potent HP  TouchSmart all-in-one. And I've used it to do real work, not lab  routines. Usually, I've run the OS in multiboot configurations with  Windows Vista and/or XP, so I've had a choice each time I turned the computer on: [MODAL] I opt for Windows 7 or an
older version of the OS? The call has been easy to make, because Win 7 is so pleasant to use.
          So why wouldn't you want to run this operating system?  Concern over its performance is one logical reason, especially  since early versions of Windows Vista managed to turn PCs that  ran XP with ease into lethargic underperformers. The PC World  Test Center's speed benchmarks on five test PCs showed  Windows 7 to be faster than Vista, but only by a little; I've found  it to be reasonably quick on every computer I've used it on - even the Asus netbook, once I upgraded it to 2GB of RAM. (Our  lab tried Win 7 on a Lenovo S10 netbook with 1GB of RAM and  found it to be a shade slower than XP; for details see "Windows 7 Performance Tests.").
           Here's a rule of thumb that errs on the side of caution: If  your PC's specs qualify it to run Vista, get Windows 7; if they  don't, avoid it. Microsoft's official hardware configuration  requirements for Windows 7 are nearly identical to those it  recommends for Windows Vista: a 1-GHz CPU, 1GB of RAM,
16GB of free disk space, and a DirectX 9-compatible graphics  device with a WDDM 1.0 or higher driver. That's for the 32-bit  version of Windows 7; the 64-bit version of the OS requires a  64-bit CPU, 2GB of RAM, and 20GB of disk space.
           Fear of incompatible hardware and software is another  understandable reason to be wary of Windows 7. One  unfortunate law of operating-system upgrades - which applies  equally to Macs and to Windows PCs - is that they will break  some systems and applications, especially at first.  
           Under the hood, Windows 7 isn't radically different from  Vista. That's a plus, since it should greatly reduce the volume of  difficulties relating to drivers and apps compared to Vista's  bumpy rollout. I have performed a half-dozen Windows 7  upgrades, and most of them went off without a hitch. The
gnarliest problem arose when I had to track down a graphics  driver for Dell's XPS M1330 laptop on my own - Windows 7  installed a generic VGA driver that couldn't run the Aero user  interface, and as a result failed to support new Windows 7  features such as thumbnail views in the Taskbar.
           The best way to reduce your odds of running into a  showstopping problem with Windows 7 is to bide your time.  When the new operating system arrives on October 22, sit back  and let the earliest adopters discover the worst snafus. Within a few weeks, Microsoft and other software and hardware   companies will have fixed most of them, and your chances of a  happy migration to Win 7 will be much higher. If you want to be really conservative, hold off on moving to Win 7 until you're  ready to buy a PC that's designed to run it well.
           Waiting a bit before making the leap makes sense;  waiting forever does not. Microsoft took far too long to come up  with a satisfactory replacement for Windows XP. But whether  you choose to install Windows 7 on your current systems or get  it on the next new PC you buy, you'll find that it's the  unassuming, thoroughly practical upgrade you've been waiting  for ? flaws and all.

                                                 (Adapted                    from  http://www.pcworld.com/article/172602/windows_7_revi...)