Psychology & Psychiatry

Mental stress plagues 44% of teenage girls in Norway

In the age of smartphones and social media, the number of adolescents and young adults in Norway with depression and anxiety has doubled. Researchers believe politicians and technology giants need to take more responsibility.

Diseases, Conditions, Syndromes

COVID restrictions ease in Shanghai as case numbers drop

Shanghai is moving to allow in-person dining and reopening its Disney Resort theme park as domestically transmitted cases of COVID-19 in China's largest city remain at zero following a more than two-month lockdown.

Diseases, Conditions, Syndromes

Big step in rapid diagnostics for infectious diseases

The speedy, high-tech method of inexpensive, accurate and high-throughput protein biomarker assay testing is being touted as a much-needed development in point-of-care (PoC) testing, say U.S. and Flinders University researchers ...

Alzheimer's disease & dementia

Does glaucoma affect cognitive function?

Previous studies have looked for links between glaucoma—a neurodegenerative disorder that's the leading cause of irreversible blindness—and cognitive function, but they've generated mixed results. Findings from a large ...

page 1 from 40

Telephone

The telephone (from the Greek: τῆλε, tēle, "far" and φωνή, phōnē, "voice") is a telecommunications device that transmits and receives sound, most commonly the human voice. It is one of the most common household appliances in the developed world, and has long been considered indispensable to business, industry and government. The word "telephone" has been adapted to many languages and is widely recognized around the world.

The device operates principally by converting sound waves into electrical signals, and electrical signals into sound waves. Such signals when conveyed through telephone networks — and often converted to electronic and/or optical signals — enable nearly every telephone user to communicate with nearly every other worldwide. Graphic symbols used to designate telephone service or phone-related information in print, signage, and other media include ℡, ☎, ☏, and ✆.

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