Flux

Flux is a simple and ubiquitous concept throughout physics and applied mathematics describing the flow of a physical property in space, frequently also with time variation. It is the basis of the field concept in physics and mathematics. There exist two common usages of the term flux, each with rigorous mathematical frameworks: For transport phenomena, flux is defined as a vector, whereas in electromagnetism, flux is a scalar quantity, as defined by the surface integral. The terms "flux", "current", "flux density", "current density", can sometimes be used interchangeably and ambiguously, though the terms used below match those of the contexts in the literature.

Origin of the term

The word flux comes from Latin: fluxus means "flow", and fluere is "to flow". As fluxion, this term was introduced into differential calculus by Isaac Newton.

Flux as flow rate per unit area

In transport phenomena (heat transfer, mass transfer and fluid dynamics), flux is defined as the rate of flow of a property per unit area, which has the dimensions [quantity]·[time]⁻¹·[area]⁻¹. For example, the magnitude of a river's current, i.e. the amount of water that flows through a cross-section of the river each second, or the amount of sunlight that lands on a patch of ground each second is also a kind of flux.

1 Month 2 Live

One Month to Live, also called 1 Month 2 Live, was a 5-issue limited series comic book produced by Marvel Comics on a weekly basis in 2010. It was written by Rick Remender in collaboration with Stuart Moore, John Ostrander, and Rob Williams. The original concept was devised by Marvel editor Steve Wacker with the premise "What would you do with one month to change the world?" The storyline centers on a protagonist with terminal cancer, in response to Wacker's aunt having been diagnosed with cancer.

The four writers found the experience of writing the story to be especially poignant, as all had personal experiences with cancer—in particular, Remender, whose father survived a bout with cancer in 2008, and Ostrander, whose wife Kim Yale died of cancer in 1997.

Plot

In an accident with toxic waste, Dennis Sykes gains superpowers and an untreatable cancer. With a life expectancy of barely a month, Sykes launches himself on a brief career as a superhero, in an attempt to make a difference in the world while he still can, assisting the Fantastic Four in saving Ego the Living Planet from a cancerous infection and averting Hammerhead's attempt to take control of his neighbourhood. Although use of his powers made his condition worse, Sykes made a positive impression on many heroes with his dedication to doing the right thing, accepting training from Spider-Man and receiving honorary membership with the FF and the Avengers before he finally died of stress from his final battle.

Flux (biology)

In general, flux in biology relates to movement of a substance between compartments. There are several cases where the concept of flux is important.

Ditch

A ditch (Dutch: sloot) is a small to moderate depression created to channel water. A ditch can be used for drainage, to drain water from low-lying areas, alongside roadways or fields, or to channel water from a more distant source for plant irrigation. A trench is a long narrow ditch. Ditches are commonly seen around farmland especially in areas that have required drainage, such as The Fens in eastern England and the Netherlands.

Roadside ditches may provide a hazard to motorists and cyclists, whose vehicles may crash into them and get damaged, flipped over or stuck, especially in poor weather conditions, and in rural areas.

In Anglo-Saxon, the word dïc already existed and was pronounced "deek" in northern England and "deetch" in the south. The origins of the word lie in digging a trench and forming the upcast soil into a bank alongside it. This practice has meant that the name dïc was given to either the excavation or the bank, and evolved to both the words "dike"/"dyke" and "ditch". Thus Offa's Dyke is a combined structure and Car Dyke is a trench, though it once had raised banks as well. In the midlands and north of England, a dike is what a ditch is in the south, a property boundary marker or small drainage channel. Where it carries a stream, it may be called a running dike as in Rippingale Running Dike, which leads water from the catchwater drain, Car Dyke, to the South Forty Foot Drain in Lincolnshire (TF1427). The Weir Dike is a soak dike in Bourne North Fen, near Twenty and alongside the River Glen.

Ditch (fortification)

A ditch in military engineering is an obstacle, designed to slow down or break up an attacking force, while a trench is intended to provide cover to the defenders. In military fortifications the side of a ditch (or gorge) farthest from the enemy and closest to the next line of defence is known as the scarp while the side of a ditch closest to the enemy is known as the counterscarp.

Uses

In early fortifications, ditches were often used in combination with ramparts to slow down the enemy whilst defensive fire could be brought to bear from the relative protection afforded by the rampart and possibly the palisade. In medieval fortification, a ditch was often constructed in front of a defensive wall to hinder mining and escalade activities from an attacker. When filled with water, such a defensive ditch is called a moat. However, moats may also be dry.

Later star forts designed by military engineers like Vauban, comprised elaborate networks of ditches and parapets, carefully calculated so that the soil for the raised earthworks was provided, as nearly as possible, entirely by the excavations whilst also maximising defensive firepower.