Commonly Confused Words:

The verb hang has two past tenses—hanged and hung. Unless you're talking about a person who has been executed ("Lord Haw-Haw was hanged for treason"), you probably want to use hung. But see the usage notes below.

Definitions

The verb hang means to fasten or suspend from above--to place something (a poster, for instance) so that it's held up without support from underneath. In a related sense, hang can mean to kill someone by putting a rope around the person's neck, attaching it to something overhead, and then causing the body to drop suddenly.

For centuries, hanged and hung were used interchangeably as the past participle of hang. However, most contemporary usage guides insist that hanged, not hung, should be used when referring to executions: convicted killers are hanged; paintings are hung. 

Examples

• Don't mention a rope in the house of someone whose father was hanged.(English proverb)
• "A room hung with pictures is a room hung with thoughts."(Joshua Reynolds)
• William Heath was hanged in January 1733 for stealing four shirts, part of somebody's washing that had been hung out to dry,
• "The sheriff's deputies, who hanged the horse thief at night, are expected to hang around until they are sober, after which they could well end up with hanged or hung looks on their faces--and hangovers for sure."
  (Robert Oliver Shipman, A Pun My Word: A Humorously Enlightened Path to English Usage. Rowman & Littlefield, 1991)

Why lb Is the Symbol for Pounds:

Have you ever wondered why we use the symbol "lb" for the "pounds" unit? The word "pound" is short for "pound weight," which was libra pondo in Latin. The libra part of the phrase meant both weight or balance scales. The Latin usage was shortened to libra, which naturally was abbreviated "lb". We adopted the pound part from pondo, yet kept the abbreviation for Libra.

There are different definitions for the mass of a pound, depending on the country.

In the United States, the modern pound unit is defined to be 2.20462234 pounds per metric kilogram. There are 16 ounces in 1 pound. However, in Roman times, the libra(pound) was about 0.3289 kilograms and was divided into 12 uncia or ounces.

In Britain, there has been more than one type of "pound", including the avoirdupois point and Troy pound. A pound sterling was a tower pound of silver, but the standard was changed to the Troy pound in 1528. The tower pound, merchant's pound, and London pound are obsolete units. The Imperial Standard Pound is defined as having a mass equal to 0.45359237 kilograms, which matches the definition of the international pound, as agreed upon (although not adopted by the U.S.) in 1959.

What Is the Moon Made Of?

The Moon is similar to the Earth in that it has a crust, mantle, and core. The composition of the two bodies is similar, which is part of why scientists think the Moon may have formed from a large impact breaking off a piece of Earth when it was forming. Scientists have samples from the surface or crust of the Moon, but the composition of the inner layers is a mystery. Based on what we know about how planets and moons form, the core of the Moon is believed to be at least partly molten and probably consists primarily of iron, with some sulfur and nickel.

The core likely is small, accounting for just 1 to 2 percent of the Moon's mass.

The Crust, Mantle, and Core of the Moon

The largest portion of the Moon is the mantle. This is the layer between the crust (the part we see) and the inner core. The lunar mantle is believed to consist of olivine, orthopyroxene, and clinopyroxene. The composition of the mantle is similar to that of the Earth, but the Moon may contain a higher percentage of iron.

Scientists have samples of the lunar crust and take measurements of properties of the Moon's surface. The crust consists of 43% oxygen, 20% silicon, 19% magnesium, 10% iron, 3% calcium, 3% aluminum, and trace amounts of other elements including 0.42% chromium, 0.18% titanium, 0.12% manganese, and smaller amounts of uranium, thorium, potassium, hydrogen and other elements. These elements form a concrete-like coating called regolith. Two types of Moon rocks have been collected from the regolith: mafic plutonic and maria basalt.

Both are types of igneous rocks, which formed from cooling lava.

The Atmosphere of the Moon

Although it is very thin, the Moon does have an atmosphere. The composition is not well known, but it is estimated to consist of helium, neon, hydrogen (H₂), argon, neon, methane, ammonia, carbon dioxide, with trace amounts of oxygen, aluminum, silicon, phosphorus, sodium, and magnesium ions.

Because conditions contrast sharply between day and night, the composition during the day may be somewhat different from the atmosphere at night. Even though the Moon has an atmosphere, it is too thin to breathe and includes compounds you wouldn't want in your lungs.

Incredible..!!

About Public Domain:

Copyrights protect works of authorship, such as writings, music, and works of art that have been expressed tangibly. This also includes movies, video games, videos, software code, choreography, and architectural designs. Currently, works no longer have to be published to be protected and do not require a copyright notice.

For older copyrights, to be "published" or publication meant the distribution of copies or phonorecords of a work (of authorship) to the public by sale, a transfer of ownership or by rental, lease or lending.

Also, the offering to distribute copies or phonorecords to a group of persons for purposes of further distribution, public performance or public display constitutes publication. A public performance or display of a work in and of itself does not constitute publication.

When Copyright Protection Becomes Public Domain

Below is a reference guide that will let you know when you can safely use a piece of art, music or other work without permission because it no longer has copyright protection and has fallen into the public domain as well as how long the copyright protection will last.

Works published prior to 1923: Anything published before 1923 is now in public domain and can be used and distributed freely.

Works published between 1923 and 1963:  If the work in question is published with a © copyright notice or "Copyright [dates] by [author/owner]," it is protected for 28 years and could be renewed again for an additional 67 years for a total of 95 years.

For example, a work copyrighted in 1923 will be in the public domain in 2019. If the work was published without a notice or if the copyright has expired, it is now in the public domain.

Works published between 1964 and 1977: When published with notice, it is copyright protected for 28 years for the first term, with an automatic extension of 67 years for the second term for a total of 95 years.

Works created before 1978, but not published: Copyright notice is irrelevant. Copyright protection lasts for the life of author plus 70 years or until the end of 2002, whichever is later.

Works created before 1978 and published between 1978 and 2002: Copyright notice is irrelevant. Copyright protection lasts throughout the life of author plus 70 years or until the end of 2047, whichever is later. 

Works created in 1978 or after: If the work is fixed in a tangible medium of expression then copyright notice is irrelevant. Copyright protection lasts for the life of the author plus 70 years and is based on the longest living author if the work was jointly created. If it is a work of corporate authorship, done for hire, or anonymous and pseudonymous work, it is protected for 95 years from publication or 120 years from creation, whichever is shorter.

How Much of a Tree Is Alive?

Only 1 percent of a dormant mature tree is biologically living while the rest is composed of non-living, structural wood cells. In other words, very little of a tree's woody volume is composed of "living, metabolizing" tissue; rather, the major living and growing portions of a tree are leaves, buds, roots, and a thin film or skin of cells just under the bark called the cambium.

There are other living cells that are important for tree growth within the different parts of trees, especially in root tips, the apical meristem, and leaf and flower buds; however, these living cells make up a very small percentage of the total volume of a tree's cells.

Instead, non-living or "dead" cells comprise most of the volume of a tree, providing vital structural support for the living cells.

Interestingly enough, trees start out in life as a germinating seed with every living cell in hyperdrive, but as a tree seed becomes a seedling, then a sapling, then a mature tree, its living contents become less and less as a percentage of the total volume. Trees increasingly lose their living cytoplasmic cells as metabolism ceases in each cell, and although they are no longer alive, these non-living cells now provide protection, transportation, and physical support for the living ones.

The Vital Role of Non-Living Cells

Without the support and structure provided by non-living cells, trees would likely die and certainly wouldn't grow quite as large as they do. This is because non-living cells provide a vital role in the process of how a tree grows — from the "heavy lifting" of holding up the tall branches to the tree's bark, which protects the thin layer of living cells underneath.

This supporting and protective wood is created by cambial-hardened cells produced on the inner and outer cambial layer and sandwiched between the outer cambial layer. As a result, the bark of a tree is a product of the ongoing process of creating sieve tubes to transport water and nutrients from the leaves to the roots and back.

The sound, non-living cells of a tree are very important to helping a tree stay protected, and the bark and structural cells serve as a line of defense against insects and disease that could affect the vulnerable living tissue of the cambium that maintains life throughout the tree.

New cells are formed and living cells cease metabolization as they transform into transport vessels and protective skin, creating a cycle of creation, rapid growth, slowing metabolism, and death as the tree climbs ever-higher into a healthy, full plant.

When Wood Is Considered Alive and Dead

For most intents and purposes, wood is considered to be the product of living cells in trees harnessing the environment around them to make proteins and form protective vessels and shells for the trees' sustained growth. Wood is only technically considered dead when it's separated from the tree itself, as it still serves a vital role in the plant's life when attached to living cells in the tree.

In other words, although wood is largely made of non-living cells — cells that no longer reproduce but instead transport nutrients to living cells — it is still considered "alive" if it is attached to the tree itself. However, if a branch falls off or a person cuts down a tree, the wood is considered "dead" because it no longer transports living matter through itself.

As a result, wood that has been separated from a tree will dry up as the protoplasm hardens and the protein turns into the wood one might use in a fireplace or for building a shelf. This wood is considered dead, though the piece it was once attached to — if still attached to the tree itself — is still considered alive. 

Flynn Effect:

You’ve probably heard someone lament the state of “kids today”: that current generations aren’t as smart as the ones that came before them. However, psychologists who study intelligence have found that there isn’t much support for this idea; instead, the opposite may actually be true. Researchers studying the Flynn effect have found that scores on IQ tests have actually improved over time. Below, we’ll review what the Flynn effect is, some possible explanations for it, and what it tells us about human intelligence.

What Is the Flynn effect?

The Flynn effect, first described in the 1980s by researcher James Flynn, refers to the finding that scores on IQ tests have increased in the past century. Researchers studying this effect have found wide support for this phenomenon. One research paper, published by psychologist Lisa Trahan and her colleagues, combined the results of other published studies (which included a total of over 14,000 participants) and found that IQ scores have indeed increased since the 1950s. Although researchers have documented some exceptions, IQ scores have generally increased over time. Trahan and her colleagues observed, “The existence of the Flynn effect is rarely disputed.”

Why Does the Flynn Effect Happen?

Researchers have put forward several theories to explain the Flynn effect. One explanation has to do with improvements in health and nutrition. For example, the past century has seen a decrease in smoking and alcohol use in pregnancy, discontinuation of the use of harmful lead paint, improvements in the prevention and treatment of infectious diseases, and improvements in nutrition.

As Scott Barry Kaufman writes for Psychology Today, “The Flynn effect serves as a reminder that when we give people more opportunities to prosper, more people do prosper.”

In other words, the Flynn effect could be partially due to the fact that, over the twentieth century, we’ve started addressing many of the public health issues that prevented people in earlier generations from reaching their full potential.

Another explanation for the Flynn effect has to do with societal changes that have occurred in the past century as a result of the Industrial Revolution. In a TED talk, Flynn explains that the world today is “a world where we've had to develop new mental habits, new habits of mind.” Flynn has found that IQ scores have increased the most rapidly on questions that ask us to find similarities between different things, and more abstract types of problem-solving — both of which are things that we need to do more of in the modern world.

Several ideas have been put forward to explain why modern society might lead to higher scores on IQ tests. For example, today, many more of us have demanding, intellectually rigorous jobs. Schools have also changed: whereas a test at school in the early 1900s might have been more focused on memorization, a recent test might be more likely to focus on explaining the reasons for something. Additionally, more people today are likely to finish high school and go on to college. Family sizes tend to be smaller, and it has been suggested that this may allow children to pick up on new vocabulary words while interacting with their parents. It’s even been suggested that the entertainment we consume is more complex today.

Trying to understand and anticipate plot points in a favorite book or TV drama may actually be making us smarter.

What Can We Learn From Studying the Flynn Effect?

The Flynn effect tells us that the human mind is much more adaptable and malleable than we might have thought. It seems that some of our thinking patterns aren’t necessarily innate, but rather things that we learn from our environment. When exposed to modern industrial society, we think about the world in different ways than our ancestors did.

When discussing the Flynn effect in The New Yorker, Malcolm Gladwell writes, “If whatever the thing is that I.Q. tests measure can jump so much in a generation, it can’t be all that immutable and it doesn’t look all that innate.” In other words, the Flynn effect tells us that IQ may not actually be what we think it is: instead of being a measure of natural, unlearned intelligence, it’s something that can be shaped by the education we receive and the society we live in.