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SUMMARY / RELATED TOPICS

Micelle

A micelle or micella is an aggregate of surfactant molecules dispersed in a liquid colloid. A typical micelle in aqueous solution forms an aggregate with the hydrophilic "head" regions in contact with surrounding solvent, sequestering the hydrophobic single-tail regions in the micelle centre; this phase is caused by the packing behavior of single-tail lipids in a bilayer. The difficulty filling all the volume of the interior of a bilayer, while accommodating the area per head group forced on the molecule by the hydration of the lipid head group, leads to the formation of the micelle; this type of micelle is known as a normal-phase micelle. Inverse micelles have the head groups at the centre with the tails extending out. Micelles are spherical in shape. Other phases, including shapes such as ellipsoids and bilayers, are possible; the shape and size of a micelle are a function of the molecular geometry of its surfactant molecules and solution conditions such as surfactant concentration, temperature, pH, ionic strength.

The process of forming micelles is known as micellisation and forms part of the phase behaviour of many lipids according to their polymorphism. The ability of a soapy solution to act as a detergent has been recognized for centuries. However, it was only at the beginning of the twentieth century that the constitution of such solutions was scientifically studied. Pioneering work in this area was carried out by James William McBain at the University of Bristol; as early as 1913, he postulated the existence of "colloidal ions" to explain the good electrolytic conductivity of sodium palmitate solutions. These mobile, spontaneously formed clusters came to be called micelles, a term borrowed from biology and popularized by G. S. Hartley in his classic book Paraffin Chain Salts: A Study in Micelle Formation; the term micelle was coined in nineteenth century scientific literature as the ‑elle diminutive of the Latin word mica, conveying a new word for "tiny particle". Individual surfactant molecules that are in the system but are not part of a micelle are called "monomers".

Micelles represent a molecular assembly, in which the individual components are thermodynamically in equilibrium with monomers of the same species in the surrounding medium. In water, the hydrophilic "heads" of surfactant molecules are always in contact with the solvent, regardless of whether the surfactants exist as monomers or as part of a micelle. However, the lipophilic "tails" of surfactant molecules have less contact with water when they are part of a micelle—this being the basis for the energetic drive for micelle formation. In a micelle, the hydrophobic tails of several surfactant molecules assemble into an oil-like core, the most stable form of which having no contact with water. By contrast, surfactant monomers are surrounded by water molecules that create a "cage" or solvation shell connected by hydrogen bonds; this water cage is similar to a clathrate and has an ice-like crystal structure and can be characterized according to the hydrophobic effect. The extent of lipid solubility is determined by the unfavorable entropy contribution due to the ordering of the water structure according to the hydrophobic effect.

Micelles composed of ionic surfactants have an electrostatic attraction to the ions that surround them in solution, the latter known as counterions. Although the closest counterions mask a charged micelle, the effects of micelle charge affect the structure of the surrounding solvent at appreciable distances from the micelle. Ionic micelles influence many properties including its electrical conductivity. Adding salts to a colloid containing micelles can decrease the strength of electrostatic interactions and lead to the formation of larger ionic micelles; this is more seen from the point of view of an effective charge in hydration of the system. Micelles form only when the concentration of surfactant is greater than the critical micelle concentration, the temperature of the system is greater than the critical micelle temperature, or Krafft temperature; the formation of micelles can be understood using thermodynamics: Micelles can form spontaneously because of a balance between entropy and enthalpy.

In water, the hydrophobic effect is the driving force for micelle formation, despite the fact that assembling surfactant molecules is unfavorable in terms of both enthalpy and entropy of the system. At low concentrations of the surfactant, only monomers are present in solution; as the concentration of the surfactant is increased, a point is reached at which the unfavorable entropy contribution, from clustering the hydrophobic tails of the molecules, is overcome by a gain in entropy due to release of the solvation shells around the surfactant tails. At this point, the lipid tails of a part of the surfactants must be segregated from the water. Hence, they start to form micelles. In broad terms, above the CMC, the loss of entropy due to assembly of the surfactant molecules is less than the gain in entropy by setting free the water molecules that were "trapped" in the solvation shells of the surfactant monomers. Important are enthalpic considerations, such as the electrostatic interactions that occur between the charged parts of surfactants.

The micelle packing parameter equation is utilized to help "predict molecular self-assembly in surfactant solutions": v o a e ℓ o where v o is the surfactant tail volume, ℓ o {\displaystyle \ell

Chamaesipho grebneffi

Chamaesipho grebneffi is the first extinct member of the Notochthamalinae to be described, the oldest chthamaloid barnacle known. This species is a derived Chamaesipho, indicates a considerable antiquity for Chthamaloidea. Three extinct species of Chthamalus from the middle Miocene of the faluns of Touraine, France were described in 2008 by Carriol; the New Zealand species is Oligocene, older. Like the three living species of Chamaesipho, the shell of C. grebneffi begins with 6 plates, fusing at about 2 mm diameter. Freegrown specimens show a stellate basal outline; the scutum is distinctive in tergal margin equal in length to basal margin. In all other Chamaesipho, tergal margin is much shorter than basal; the tergum is not identified. Chamaesipho grebneffi is interpreted, from wear patterns on the shell, to have occupied high littoral positions on shore. Entire assemblage described by Buckeridge indicates shallow agitated waters of several habitat zones. Chamaesipho brunnea Moore. Buckeridge, 1983b: 80.

Chamaesipho grebneffi Buckeridge, 2014: 7. Type locality: late Oligocene, Chatton Formation, Cosy Dell farm, Southland,New Zealand. Known only from this locality. Data related to Chamaesipho grebneffi at Wikispecies

Fibonacci heap

In computer science, a Fibonacci heap is a data structure for priority queue operations, consisting of a collection of heap-ordered trees. It has a better amortized running time than many other priority queue data structures including the binary heap and binomial heap. Michael L. Fredman and Robert E. Tarjan developed Fibonacci heaps in 1984 and published them in a scientific journal in 1987. Fibonacci heaps are named after the Fibonacci numbers, which are used in their running time analysis. For the Fibonacci heap, the find-minimum operation takes constant amortized time; the insert and decrease key operations work in constant amortized time. Deleting an element works in O amortized time, where n is the size of the heap; this means that starting from an empty data structure, any sequence of a insert and decrease key operations and b delete operations would take O worst case time, where n is the maximum heap size. In a binary or binomial heap such a sequence of operations would take O time. A Fibonacci heap is thus better than a binary or binomial heap when b is smaller than a by a non-constant factor.

It is possible to merge two Fibonacci heaps in constant amortized time, improving on the logarithmic merge time of a binomial heap, improving on binary heaps which cannot handle merges efficiently. Using Fibonacci heaps for priority queues improves the asymptotic running time of important algorithms, such as Dijkstra's algorithm for computing the shortest path between two nodes in a graph, compared to the same algorithm using other slower priority queue data structures. A Fibonacci heap is a collection of trees satisfying the minimum-heap property, that is, the key of a child is always greater than or equal to the key of the parent; this implies. Compared with binomial heaps, the structure of a Fibonacci heap is more flexible; the trees do not have a prescribed shape and in the extreme case the heap can have every element in a separate tree. This flexibility allows some operations to be executed in a lazy manner, postponing the work for operations. For example, merging heaps is done by concatenating the two lists of trees, operation decrease key sometimes cuts a node from its parent and forms a new tree.

However, at some point order needs to be introduced to the heap to achieve the desired running time. In particular, degrees of nodes are kept quite low: every node has degree at most O and the size of a subtree rooted in a node of degree k is at least Fk+2, where Fk is the kth Fibonacci number; this is achieved by the rule. When a second child is cut, the node itself needs to be cut from its parent and becomes the root of a new tree; the number of trees is decreased in the operation delete minimum. As a result of a relaxed structure, some operations can take a long time while others are done quickly. For the amortized running time analysis we use the potential method, in that we pretend that fast operations take a little bit longer than they do; this additional time is later combined and subtracted from the actual running time of slow operations. The amount of time saved for use is measured at any given moment by a potential function; the potential of a Fibonacci heap is given by Potential = t + 2mwhere t is the number of trees in the Fibonacci heap, m is the number of marked nodes.

A node is marked if at least one of its children was cut since this node was made a child of another node. The amortized time for an operation is given by the sum of the actual time and c times the difference in potential, where c is a constant. Thus, the root of each tree in a heap has one unit of time stored; this unit of time can be used to link this tree with another tree at amortized time 0. Each marked node has two units of time stored. One can be used to cut the node from its parent. If this happens, the node becomes a root and the second unit of time will remain stored in it as in any other root. To allow fast deletion and concatenation, the roots of all trees are linked using a circular doubly linked list; the children of each node are linked using such a list. For each node, we maintain its number of children. Moreover, we maintain a pointer to the root containing the minimum key. Operation find, it does not change the potential of the heap, therefore both actual and amortized cost are constant.

As mentioned above, merge is implemented by concatenating the lists of tree roots of the two heaps. This can be done in constant time and the potential does not change, leading again to constant amortized time. Operation insert works by doing merge; this takes constant time, the potential increases by one, because the number of trees increases. The amortized cost is thus still constant. Operation extract minimum operates in three phases. First we remove it, its children will become roots of new trees. If the number of children was d, it takes time O to process all new roots and the potential increases by d−1. Therefore, the amortized running time of this phase is O = O; however to complete the extract minimum operation, we need to update the pointer to the root with minimum key. There may be up to n roots we need to check

AM Conspiracy (album)

AM Conspiracy is the debut album by American Alternative metal band AM Conspiracy. The album was recorded in early 2009 at Belle City Sound in Racine, Wisconsin with Chris Wisco, who plays bass in Novembers Doom; the first single off album, "Pictures", was mixed by Randy Staub, who has worked with Metallica, Alice In Chains and most Thousand Foot Krutch, among others. However, according to fmqb.com the band released. Frontman Jones told AOL's Noisecreep about album, "It's 13 songs, all different from each other. We try to keep it going. We did it because a lot of records that have been coming out in my opinion, sound like one long song. We try to steer away from that as far as possible. So it's got a good mixture of different emotions that it'll take people through, it has different kinds of music. Some stuff's real heavy; some stuff's pretty light." Stephen Jensen photographed the band last spring when they were recording the album up in Racine, WI, was asked to create the album artwork for their debut.

AM Conspiracy singer Jason "Gong" Jones, who himself is an accomplished tattoo artist, contacted Stephen with several different concepts for the cover of his debut album during the course of recording. Stephen and Jason hit it off and began bouncing ideas back and forth; when Jason came up with the idea to do a stylized version of a dollar bill with altered and hidden imagery it took a bit of "selling" to the record label. Stephen sat down with Jason to help expand the idea and bring his vision to life. For the main image on the cover, Jason wanted to feature the band's faces carved over the sculpture of Mount Rushmore with a radio antenna on the top of the mountain spreading the AM Conspiracy message; the photo would appear as part of the engraving on an altered one dollar bill. Stephen used some of the stylized filigrees that appear on the one dollar bill and played into the conspiracy theories regarding hidden imagery that are mixed into the engravings on the original currency design. Stephen and Jason worked together to carry the conspiracy theory imagery throughout the rest of the album artwork including the layout of Washington DC, UFO and alien implants, the Paul McCartney death hoax, the JFK magic bullet theory, the Lincoln assassination, the faked lunar landing.

Gong made a late night call to Stephen after seeing the first draft of the album cover. He was blown away that Stephen was able to take the vision as it appeared in his head several steps further. Jason "Gong" Jones - lead vocals, Cover Art Concept Dean Andrews - drums Kenny Harrelson - bass Drew Burke - lead guitar, backing vocals Rob DeHaven - rhythm guitar Chris Wisco - Producer, Mixing Randy Staub - Mixing Heath Starling - Photography Stephen Jensen - Art Direction, Cover Art Concept Shaun Glass - A&R Official Website Official MySpace Official AM Conspiracy Twitter AM Conspiracy Label

1977 Australian Open (January)

The 1977 Australian Open was a tennis tournament played on outdoor grass courts at the Kooyong Stadium in Melbourne, Australia. The tournament was held from 3 to 9 January 1977. Due to a scheduling change two Australian Opens took place in 1977 with the second taking place in December. Roscoe Tanner defeated Guillermo Vilas, 6–3, 6–3, 6–3 It was Tanner's 1st career Grand Slam title. Kerry Melville Reid defeated Dianne Fromholtz, 7–5, 6–2 It was Melville's 1st career Grand Slam title. Arthur Ashe / Tony Roche defeated Charlie Pasarell / Erik van Dillen, 6–4, 6–4 Dianne Fromholtz / Helen Gourlay defeated Kerry Melville Reid / Betsy Nagelsen, 5–7, 6–1, 7–5 Competition not held between 1970 and 1986. Brad Drewett Pamela Baily

Sound-on-film

Sound-on-film is a class of sound film processes where the sound accompanying a picture is recorded onto photographic film but not always, the same strip of film carrying the picture. Sound-on-film processes can either record an analog sound track or digital sound track, may record the signal either optically or magnetically. Earlier technologies were sound-on-disc, meaning the film's soundtrack would be on a separate phonograph record; the most prevalent current method of recording analogue sound on a film print is by stereo variable-area recording, a technique first used in the mid-1970s as Dolby Stereo. A two-channel audio signal is recorded as a pair of lines running parallel with the film's direction of travel through the projector's screen; the lines change area depending on the magnitude of the signal. The projector shines light from a small lamp, called an exciter, through a perpendicular slit onto the film; the image on the small slice of exposed track modulates the intensity of the light, collected by a photosensitive element: a photocell, a photodiode or CCD.

In the early years of the 21st century distributors changed to using cyan dye optical soundtracks on color stocks instead of applicated tracks, which use environmentally unfriendly chemicals to retain a silver soundtrack. Because traditional incandescent exciter lamps produce copious amounts of infra-red light, cyan tracks do not absorb infra-red light, this change has required theaters to replace the incandescent exciter lamp with a complementary colored red LED or laser; these LED or laser exciters are backwards-compatible with older tracks. Earlier processes, used on 70 mm film prints and special presentations of 35 mm film prints, recorded sound magnetically on ferric oxide tracks bonded to the film print, outside the sprocket holes. 16 mm and Super 8 formats sometimes used a similar magnetic track on the camera film, bonded to one side of the film on which the sprocket holes had not been punched for the purpose. Film of this form is no longer manufactured, but single-perforated film without the magnetic track or, in the case of 16 mm, utilising the soundtrack area for a wider picture is available.

Three different digital soundtrack systems for 35 mm cinema release prints were introduced during the 1990s. They are: Dolby Digital, stored between the perforations on the sound side; because these soundtrack systems appear on different parts of the print, one movie can contain all of them, allowing broad distribution without regard for the sound system installed at individual theatres. All sound formats used with motion-picture film have been sound-on-film formats, including: Fox/Western Electric Movietone, are variable-density formats of sound film. Tri-Ergon, another variable-density format prevalent in Europe until the 1940s; the US patent rights of this Berlin based company were bought by William Fox in 1926, leading to a patent war with the US film industry lasting until 1935. Tri-Ergon amalgamated with a number of other German competitors from 1928 to form the Dutch-controlled Tobis Film syndicate in 1930, licensing the system to Ufa as Ufa-Klang. RCA Photophone, a variable-area format now universally used for optical analog soundtracks—since the late 1970s with a Dolby encoding matrix.

Dolby Stereo Dolby SR Ultra Stereo Dolby Digital Sony Dynamic Digital Sound Cinema Digital Sound, an optical format, the first commercial digital sound format, used between 1990 and 1992 Fantasound. This was a system developed by RCA and Disney Studios with a multi-channel soundtrack recorded on a separate strip of film from the picture, it was used for the initial release of Walt Disney's Fantasia Phonofilm, patented by Lee De Forest in 1919, defunct by 1929 Charles A. Hoxie List of film formats List of film sound systems Movietone sound system Optigan Phonofilm RCA Photophone Eugène Lauste Joseph Tykociński-Tykociner Multichannel Film Sound