Psychology & Psychiatry

Psychological forest: What trees reveal about Antarctic researchers

At the bottom of the world, there's a small island about four kilometers off the coast of Antarctica. In summer, temperatures climb to freezing with uninterrupted daylight for two months. In winter, they fall to minus 40 ...

Medical research

Understanding the evolution of SARS and COVID-19 type viruses

As COVID-19 sweeps the world, related viruses quietly circulate among wild animals. A new study shows how SARS-CoV-2, the virus that causes COVID-19, and SARS-CoV-1, which caused the 2003 SARS outbreak, are related to each ...

Diseases, Conditions, Syndromes

Coronavirus introduced into Russia at least 67 times

A research team from HSE University and SkolTech, together with experts from the Smorodintsev Research Institute of Influenza in St. Petersburg and the RAS Kharkevich Institute for Information Transmission Problems (IITP) ...

Psychology & Psychiatry

Street trees close to the home may reduce the risk of depression

Depression, especially in urban areas, is on the rise, now more than ever. Mental health outcomes are influenced by, among other things, the type of environment where one lives. Former studies show that urban greenspace has ...

Diseases, Conditions, Syndromes

Ukraine imposes virus lockdown that many say came too late

Ukraine on Friday imposed a broad lockdown aimed at containing surging coronavirus infections, but some cities appeared to be largely ignoring the restrictions and critics said the move was worrisomely tardy.

Immunology

What is cedar fever? Experts explain Texas winter irritant

Cedar fever season is almost upon us, and at a time when having a fever—or even catching a slight cold—is concerning, it's more important than ever to understand the symptoms and source of this common Central Texas allergy.

Health

Do the benefits of Christmas outweigh its harms?

The Christmas season is associated with preventable harms from cards, tree decorations, and presents, as well as overeating and overdrinking, so do the benefits of Christmas outweigh the harms?

Diseases, Conditions, Syndromes

Identifying markers of COVID-19 infection using blood tests

Researchers from the Institute of Biomedicine of Seville (IBIS) have presented a study carried out in the Clinical Biochemistry Service of the Virgen del Rocío University Hospital which identifies the values for six biochemical ...

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Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to 6 m; some authors set a minimum of 10 cm trunk diameter (30 cm girth). Woody plants that do not meet these definitions by having multiple stems and/or small size, are called shrubs. Compared with most other plants, trees are long-lived, some reaching several thousand years old and growing to up to 115 m (379 ft) high.

Trees are an important component of the natural landscape because of their prevention of erosion and the provision of a weather-sheltered ecosystem in and under their foliage. Trees also play an important role in producing oxygen and reducing carbon dioxide in the atmosphere, as well as moderating ground temperatures. They are also elements in landscaping and agriculture, both for their aesthetic appeal and their orchard crops (such as apples). Wood from trees is a building material, as well as a primary energy source in many developing countries. Trees also play a role in many of the world's mythologies (see trees in mythology).

This text uses material from Wikipedia, licensed under CC BY-SA