What is Thermal Energy

Thermal energy is generated and measured by heat of any kind. It is caused by the increased activity or velocity of molecules in a substance, which in turn causes temperature to rise accordingly. There are many natural sources of thermal energy on Earth, making it an important component of alternative energy.

The laws of thermodynamics explain that energy in the form of heat can be exchanged from one physical object to another. For instance, putting fire under a pot of water will cause the water to heat up as a result of the increased molecular movement. In that way, the heat, or thermal energy, of the fire, is partially transmitted to the water.

Understanding the principles of thermodynamics has allowed human beings to harness natural sources of heat to create thermal energy out of a variety of sources. The sun, ocean, and geothermal sources such as geysers and volcanoes, can all be sources of thermal energy. As humans attempt to turn to sustainable forms of alternative energy instead as fossil fuel resources become depleted, much attention has been focused on improving methods of harnessing thermal energy to power human activity.

Solar thermal power is one of the most commonly used forms of thermal energy. Although gathering solar power is only available when the sun is visible in the sky, scientists have developed many different ways of storing and utilizing the power absorbed by solar devices. On a small level, a person can heat his or her pool by placing low-temperature collecting systems in or around the water. By absorbing sunlight and distributing it to the water, the temperature is increased throughout the day and even after the sun has set. Solar panels, evaporation pools, and other advanced systems can perform this function on a much more wide-spread level, creating enough stored power to run a factory or even city on solar thermal power.

The Earth is constructed around a molten core of incredible heat that lessens considerably as it reaches the surface or crust level. Yet by harnessing some of the heat generated below the surface of the planet, humans can extract enormous amounts of energy. The simplest way to do this is through geothermal energy sources such as geysers, or at the boundaries of tectonic plates. Geothermal wells pump out energy in the form of hot water or steam that can be converted into usable energy, or simply used directly. 

Thermal energy is an awesome force that is just beginning to be fully understood. By creating new devices and methods to concentrate, store, and transport naturally-created thermal energy, human beings can reduce dependence on non-sustainable forms of energy. Thanks to the power of heat, hot baths, boiled water, and thermally-powered cities are all possible.

Why Does Bread get Moldy

Bread gets moldy because it provides a good source of food for some types of fungus. The air is usually full of tiny mold spores, and under the right conditions, they can settle on nearly any organic substance and start to digest it. In bread, these enzymes break down the cell walls of the organic material making up the loaf, releasing easily digestible, molecularly simple compounds. This is how bread gets moldy.

Mold, found on old or unrefrigerated bread, comes from fungi, one of the most ubiquitous and successful forms of life on the planet. There are dozens of thousands of species, which can be found practically everywhere. Scientists who study fungi, called mycologists, tell say that approximately one out of every 20 living species is a form of fungus.

Fungi cannot receive energy directly from the sun because they do not have chlorophyll, and must therefore live off other plants and animals. Some fungi are parasites, actively attacking a host for nutrients. Most, however, are scavengers, turning organic matter into soil. Without fungi, many plants would die, because they require rich soil to thrive.

Most fungi tend to be flexible about their food choices. They feed on a wide variety of organic molecules, and their flexibility is largely responsible for their ubiquity. Fungi produce dozens of digestive enzymes and acids, which they secrete into a material as they grow over it. 

Unlike humans, mold digests first, then eats, rather than vice versa. Under the right conditions, there exist forms of fungi that eat practically anything but metal. Special fungi produced through selective breeding are sometimes used as agents to target specific compounds for cleanup. 

Fungi reproduce exponentially until all available nutrients are exhausted. Some forms of mold can double their mass every hour. They reproduce by means of spores, tiny vectors which are produced by the fungus en masse. Spores are extremely small and numerous — there are probably millions of fungal spores in any room at one time. 

Luckily, these spores can be destroyed by cooking, which is why bread doesn't immediately get infected with mold. Over time, however, airborne spores find their way onto the nutrient-rich surface of bread and start multiplying — even under the cold conditions of a refrigerator. At freezing point, fungi become dormant. If they are exposed to heat again, they can revive and continue to grow.

What are Hypnagogic Hallucinations

Hypnagogic hallucinations are hallucinations which occur at the boundary between sleeping and waking. They can occur when people are falling asleep, or when they are starting to wake up, and they tend to be extremely vivid, feeling like a Technicolor Oz after the black and white Kansas of every day life. Many people experience hypnagogic hallucinations at some point during their lives, but recurrent intense hallucinations can be a sign of an underlying medical condition which may require treatment.

Visual, auditory, tactile, and kinetic sensations can all be experienced during hypnagogic hallucinations, and everyone experiences slightly different forms. Some people, for example, may feel like they are falling, and jerk themselves awake to avoid hitting the ground. Others may hear voices as they are trying to drift off to sleep, or experience a vivid sensation that someone or something is in the room. Sensory experiences such as feeling like one is submerged in a pool of water are also not uncommon.

In some cases, hypnagogic hallucinations can be frightening for the people who experience them. They may include vivid and frightening images, including images which are out of scale, which can make the hallucinations seem even more unsettling; people may see giant spiders on the walls, for example, or feel like they have shrunk down to a tiny size in the bed. The vivid experiences may also be brought to mind over the course of the day, causing inexplicable images or sensations to filter through someone's consciousness at an unexpected moment.

The cause of hypnagogic hallucinations is not fully understood. These hallucinations tend to be more common in people with sleep disorders, especially narcolepsy, but they can also appear as a side effect related to prescription drugs, and drug abusers often experience them as well. Hypnagogic hallucinations tend to be more common in young people, especially children, which may be because their minds are still developing and forming pathways, which can occasionally lead to some crossed wires.

If someone experiences numerous hypnagogic hallucinations, repetitive or not, it is a good idea to see a doctor to check for health problems which could be related to the experiences. If no cause is evident, a psychologist or similar mental health professional might be able to explore the subconscious causes and help the patient deal with the hallucinations. Consulting a psychologist can also yield useful tips for people who are shaken or upset by hypnagogic hallucinations, even if the hallucinations continue to occur.