Computers and health


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Computers and health

Our computer can have adverse effects on our health. Have you ever heard of carpal tunnel syndrome? This painful condition is quite common. It is a consequence of working at a computer for long periods of time. Computer users are now being warned about another computer-related illness. This one is called computer vision syndrome. Symptoms include headaches, blurred vision, light sensitivity, and difficulty in focusing. Experts recommend that people who work long hours on a computer should get more frequent eye exams. Some may need special glasses designed for computer use.



Climate change

Weather is the state of the atmosphere—its temperature, humidity, wind, rainfall and so on—over hours to weeks. It is influenced by the oceans, land surfaces and ice sheets, which together with the atmosphere form what is called the ‘climate system’. Climate, in its broadest sense, is the statistical description of the state of the climate system. Climate change is a change in the statistical properties of the climate system that persists for several decades or longer—usually at least 30 years. These statistical properties include averages, variability and extremes. Climate change may be due to natural processes, such as changes in the Sun’s radiation, volcanoes or internal variability in the climate system, or due to human influences such as changes in the composition of the atmosphere or land use.



Deforestation

Deforestation and forest degradation can happen quickly, such as when a forest is clear-cut to make way for a palm oil plantation or a new settlement. It can also happen gradually as a result of ongoing forest degradation as temperatures rise due to climate change caused by human activity. The most common pressures causing deforestation and severe forest degradation are agriculture, unsustainable forest management, mining, infrastructure projects and increased fire incidence and intensity. Some infrastructure activities, such as road building, have a large indirect effect through opening up forests to settlers and agriculture. Poor forest management and unsustainable fuelwood collection degrade forests and often instigate a "death by a thousand cuts" form of deforestation. Illegal logging occurs in all types of forests across all continents – from Brazil to Indonesia – destroying nature and wildlife, taking away community livelihoods and distorting trade. Illegally harvested wood finds its way into major consumption markets.

Nuclear energy

As the world attempts to transition its energy systems away from fossil fuels towards low-carbon sources of energy, we have a range of energy options: renewable energy technologies such as hydropower, wind and solar, but also nuclear power. Nuclear energy and renewable technologies typically emit very little CO2 per unit of energy production, and are also much better than fossil fuels in limiting levels of local air pollution. But whilst some countries are investing heavily in increasing their nuclear energy supply, others are taking their plants offline. The role that nuclear energy plays in the energy system is therefore very specific to the given country.



About whales

Whales, dolphins and porpoises belong to an aquatic marine mammal group called Cetaceans. There are over 86 species of Cetaceans. Whales are divided into the following groups: Toothed whales and Baleen whales. Any whales are very acrobatic, even breaching (jumping) high out of the water and then slapping the water as they come back down. Sometimes they twirl around while breaching. Breaching may be purely for play or may be used to loosen skin parasites or might have some social meaning.  Complex whale’s songs can be heard for miles under the water. The humpback’s song can last for 30 minutes. Baleen whales sing low-frequency songs. Toothed whales emit whistles and clicks that they use for echolocation. The songs are thought to be used in attracting mates, to keep track of offspring, and for the Toothed whales, to locate prey.  Cetaceans have very strong social ties. The strongest social ties are between mother and calf. The Toothed whales travel in large, sometimes stable pods. They frequently hunt their prey in groups, migrate together, and share care of their young.
Robots in our daily lives

Technically robots are automatic motorized tools, but they're generally known as clunky humanoid foils that have bumbled about popular media for almost a century - mechanized characters of humor, or menace without status, rendering their violent removal a minor plot without guilt. Boom, there goes another one. The hero saves the day. Sad actually. Mobile robots have gotten a bad rap from a lot of prejudicial movies and video games, and not the least from the unfulfilled promises of the 20th century. Right now all modern technology is designed to bring the world to you; phone, radio, television, internet, but if trends continue, robots will soon bring you to the world, everywhere, and at the speed of thought. A mind and a hand where it's needed while you sit safely at home and run the show. It's a future goal -- something we know we can do if we can urge the market towards it, but it's one I like, and might even be able to do something about.



Animal behavior

The study of animal behavior is one of the fastest growing sub-disciplines in biology. The resulting diversity of conceptual approaches and methodological innovations makes it increasingly difficult for professionals and students to keep abreast of important new developments. This edited volume provides up-to-date reviews that facilitate orientation in key areas of animal behavior, including communication, cognition, conflict, cooperation and behavioral variation. The contributions address evolutionary and proximate aspects of behavior and also cover both invertebrates and vertebrates. Important concepts are dealt with in separate glossaries and key examples highlighted in separate text boxes. Richly illustrated with color figures, this volume offers a well structured overview of all the main developments in current animal behavior research. It is ideal for teaching upper-level courses, where it will be essential reading for advanced students familiar with basic concepts and ideas.
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