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Mag-Thor | Alloys | Magnesium-thorium alloys have been used in several military applications, particularly in missile construction. The most noted example of this is the ramjet components in the CIM-10 Bomarc missile and Lockheed D-21 drone, which implemented thoriated magnesium in their engine construction. This is due to thoriated magnesium alloys being lightweight, having high strength, and creep resistance up to 350 °C. But, these alloys are no longer used due to radiation concerns involving thorium's radioactivity. This has resulted in several missiles being removed from public display. Similarly, the structure of the Equipment and Retro-Rocket Modules of the Gemini spacecraft (the white-painted portions) were made of thoriated magnesium for their strength-to-weight ratio and thermal properties. These were not part of the inhabited cabin, though the radiator tubing, whose silicone coolant flowed through the cabin, was also made of the same material. All examples burned up in the atmosphere upon reentry. |
Mag-Thor | Alloys | Another concern for the thoriated magnesium alloys is the low melting point and rapid oxidation of the metal. This can result in dangerous flash fires during the production of the alloys. Additionally, thorium-free magnesium alloys have been developed that exhibit similar characteristics to mag-thor, causing currently used magnesium-thorium alloys to be cycled out of use. |
BSAFE | BSAFE | Dell BSAFE, formerly known as RSA BSAFE, is a FIPS 140-2 validated cryptography library, available in both C and Java. BSAFE was initially created by RSA Security, which was purchased by EMC and then, in turn, by Dell. When Dell sold the RSA business to Symphony Technology Group in 2020, Dell elected to retain the BSAFE product line. BSAFE was one of the most common encryption toolkits before the RSA patent expired in September 2000. It also contained implementations of the RCx ciphers, with the most common one being RC4. From 2004 to 2013 the default random number generator in the library was a NIST-approved RNG standard, widely known to be insecure from at least 2006, containing a kleptographic backdoor from the American National Security Agency (NSA), as part of its secret Bullrun program. In 2013 Reuters revealed that RSA had received a payment of $10 million to set the compromised algorithm as the default option. The RNG standard was subsequently withdrawn in 2014, and the RNG removed from BSAFE beginning in 2015. |
BSAFE | Cryptography backdoors | Dual_EC_DRBG random number generator From 2004 to 2013, the default cryptographically secure pseudorandom number generator (CSPRNG) in BSAFE was Dual_EC_DRBG, which contained an alleged backdoor from NSA, in addition to being a biased and slow CSPRNG. The cryptographic community had been aware that Dual_EC_DRBG was a very poor CSPRNG since shortly after the specification was posted in 2005, and by 2007 it had become apparent that the CSPRNG seemed to be designed to contain a hidden backdoor for NSA, usable only by NSA via a secret key. In 2007, Bruce Schneier described the backdoor as "too obvious to trick anyone to use it." The backdoor was confirmed in the Snowden leaks in 2013, and it was insinuated that NSA had paid RSA Security US$10 million to use Dual_EC_DRBG by default in 2004, though RSA Security denied that they knew about the backdoor in 2004. The Reuters article which revealed the secret $10 million contract to use Dual_EC_DRBG described the deal as "handled by business leaders rather than pure technologists". RSA Security has largely declined to explain their choice to continue using Dual_EC_DRBG even after the defects and potential backdoor were discovered in 2006 and 2007, and has denied knowingly inserting the backdoor. |
BSAFE | Cryptography backdoors | So why would RSA pick Dual_EC as the default? You got me. Not only is Dual_EC hilariously slow – which has real performance implications – it was shown to be a just plain bad random number generator all the way back in 2006. By 2007, when Shumow and Ferguson raised the possibility of a backdoor in the specification, no sensible cryptographer would go near the thing. And the killer is that RSA employs a number of highly distinguished cryptographers! It's unlikely that they'd all miss the news about Dual_EC. |
BSAFE | Cryptography backdoors | As a cryptographically secure random number generator is often the basis of cryptography, much data encrypted with BSAFE was not secure against NSA. Specifically it has been shown that the backdoor makes SSL/TLS completely breakable by the party having the private key to the backdoor (i.e. NSA). Since the US government and US companies have also used the vulnerable BSAFE, NSA can potentially have made US data less safe, if NSA's secret key to the backdoor had been stolen. It is also possible to derive the secret key by solving a single instance of the algorithm's elliptic curve problem (breaking an instance of elliptic curve cryptography is considered unlikely with current computers and algorithms, but a breakthrough may occur). |
BSAFE | Cryptography backdoors | In June 2013, Edward Snowden began leaking NSA documents. In November 2013, RSA switched the default to HMAC DRBG with SHA-256 as the default option. The following month, Reuters published the report based on the Snowden leaks stating that RSA had received a payment of $10 million to set Dual_EC_DRBG as the default.With subsequent releases of Crypto-C Micro Edition 4.1.2 (April 2016), Micro Edition Suite 4.1.5 (April 2016) and Crypto-J 6.2 (March 2015), Dual_EC_DRBG was removed entirely. |
BSAFE | Cryptography backdoors | Extended Random TLS extension "Extended Random" was a proposed extension for the Transport Layer Security (TLS) protocol, submitted for standardization to IETF by an NSA employee, although it never became a standard. The extension would otherwise be harmless, but together with the Dual_EC_DRBG, it would make it easier to take advantage of the backdoor.The extension was previously not known to be enabled in any implementations, but in December 2017, it was found enabled on some Canon printer models, which use the RSA BSAFE library, because the extension number conflicted a part of TLS version 1.3. |
BSAFE | Varieties | Crypto-J is a Java encryption library. In 1997, RSA Data Security licensed Baltimore Technologies' J/CRYPTO library, with plans to integrate it as part of its new JSAFE encryption toolkit and released the first version of JSAFE the same year. JSAFE 1.0 was featured in the January 1998 edition of Byte magazine.
Cert-J is a Public Key Infrastructure API software library, written in Java. It contains the cryptographic support necessary to generate certificate requests, create and sign digital certificates, and create and distribute certificate revocation lists. As of Cert-J 6.2.4, the entire API has been deprecated in favor of similar functionality provided BSAFE Crypto-J JCE API.
BSAFE Crypto-C Micro Edition (Crypto-C ME) was initially released in June 2001 under the name "RSA BSAFE Wireless Core 1.0". The initial release targeted Microsoft Windows, EPOC, Linux, Solaris and Palm OS. |
BSAFE | Varieties | BSAFE Micro Edition Suite is a cryptography SDK in C. BSAFE Micro Edition Suite was initially announced in February 2002 as a combined offering of BSAFE SSL-C Micro Edition, BSAFE Cert-C Micro Edition and BSAFE Crypto-C Micro Edition. Both SSL-C Micro Edition and Cert-C Micro Edition reached EOL in September 2014, while Micro Edition Suite remains supported with Crypto-C Micro Edition as its FIPS-validated cryptographic provider. |
BSAFE | Varieties | SSL-C is an SSL toolkit in the BSAFE suite. It was originally written by Eric A. Young and Tim J. Hudson, as a fork of the open library SSLeay, that they developed prior to joining RSA. SSL-C reached End Of Life in December 2016.
SSL-J is a Java toolkit that implements TLS. SSL-J was released as part of RSA JSAFE initial product offering in 1997. Crypto-J is the default cryptographic provider of SSL-J. |
BSAFE | Product suite support status | On November 25, 2015, RSA announced End of Life (EOL) dates for BSAFE. The End of Primary Support (EOPS) was to be reached on January 31, 2017, and the End of Extended Support (EOXS) was originally set to be January 31, 2019. That date was later further extended by RSA for some versions until January 31, 2022. During Extended Support, even though the support policy stated that only the most severe problems would be patched, new versions were released containing bugfixes, security fixes and new algorithms.On December 12, 2020, Dell announced the reversal of RSA's past decision, allowing BSAFE product support beyond January 2022 as well as the possibility to soon acquire new licenses. Dell also announced it was rebranding the toolkits to Dell BSAFE. |
Worse-than-average effect | Worse-than-average effect | The worse-than-average effect or below-average effect is the human tendency to underestimate one's achievements and capabilities in relation to others.It is the opposite of the usually pervasive better-than-average effect (in contexts where the two are compared or the overconfidence effect in other situations). It has been proposed more recently to explain reversals of that effect, where people instead underestimate their own desirable traits. |
Worse-than-average effect | Worse-than-average effect | This effect seems to occur when chances of success are perceived to be extremely rare. Traits which people tend to underestimate include juggling ability, the ability to ride a unicycle, the odds of living past 100 or of finding a U.S. twenty dollar bill on the ground in the next two weeks.
Some have attempted to explain this cognitive bias in terms of the regression fallacy or of self-handicapping. In a 2012 article in Psychological Bulletin it is suggested the worse-than-average effect (as well as other cognitive biases) can be explained by a simple information-theoretic generative mechanism that assumes a noisy conversion of objective evidence (observation) into subjective estimates (judgment). |
Certified Wireless Security Professional | Certified Wireless Security Professional | The Certified Wireless Security Professional (CWSP) is an advanced level certification that measures the ability to secure any wireless network.A wide range of security topics focusing on the 802.11 wireless LAN technology are covered in the coursework and exam, which is vendor neutral. |
Certified Wireless Security Professional | Certification track | The CWSP certification is awarded to candidates who pass the CWSP exam and who also hold the CWNA certification. The CWNA certification is a prerequisite to earning the CWSP certification. |
Certified Wireless Security Professional | CWSP requirements | This certification covers a wide range of security areas. These include detecting attacks, wireless analysis, policy, monitoring and solutions. |
Certified Wireless Security Professional | Recertification | The CWSP certification is valid for three years. The certification may be renewed by retaking the CWSP exam or by advancing on to CWNE which is also valid for 3 years. |
Cocos2d | Cocos2d | Cocos2d is an open-source game development framework for creating 2D games and other graphical software for iOS, Android, Windows, macOS, Linux, HarmonyOS, OpenHarmony and web platforms. It is written in C++ and provides bindings for various programming languages, including C++, C#, Lua, and JavaScript. The framework offers a wide range of features, including physics, particle systems, skeletal animations, tile maps, and others. Cocos2d was first released in 2008, and was originally written in Python. It contains many branches with the best known being Cocos2d-ObjC (formerly known as Cocos2d-iPhone), Cocos2d-x, Cocos2d-JS and Cocos2d-XNA. There are also many third-party tools, editors and libraries made by the Cocos2d community, such as particle editors, spritesheet editors, font editors, and level editors, like SpriteBuilder and CocoStudio. |
Cocos2d | Sprites and scenes | All versions of Cocos2d work using the basic primitive known as a sprite. A sprite can be thought of as a simple 2D image, but can also be a container for other sprites. In Cocos2D, sprites are arranged together to form a scene, like a game level or a menu. Sprites can be manipulated in code based on events or actions or as part of animations. The sprites can be moved, rotated, scaled, have their image changed, etc. |
Cocos2d | Features | Animation Cocos2D provides basic animation primitives that can work on sprites using a set of actions and timers. They can be chained and composed together to form more complex animations. Most Cocos2D implementations let you manipulate the size, scale, position, and other effects of the sprite. Some versions of Cocos2D let you also animate particle effects, image filtering effects via shaders (warp, ripple, etc.). |
Cocos2d | Features | GUI Cocos2D provides primitives to representing common GUI elements in game scenes. This includes things like text boxes, labels, menus, buttons, and other common elements.
Physics system Many Cocos2D implementations come with support for common 2D physics engines like Box2D and Chipmunk.
Audio Various versions of Cocos2D have audio libraries that wrap OpenAL or other libraries to provide full audio capabilities. Features are dependent on the implementation of Cocos2D.
Scripting support Support binding to JavaScript, Lua, and other engines exist for Cocos2D. For example, Cocos2d JavaScript Binding (JSB) for C/C++/Objective-C is the wrapper code that sits between native code and JavaScript code using Mozilla's SpiderMonkey. With JSB, you can accelerate your development process by writing your game using easy and flexible JavaScript. |
Cocos2d | Features | Editor support End of life support SpriteBuilder: Previously known as CocosBuilder, SpriteBuilder is an IDE for Cocos2D-SpriteBuilder apps. SpriteBuilder is free and its development was sponsored by Apportable, who also sponsored the free Cocos2D-SpriteBuilder, Cocos3D, and Chipmunk physics projects. It was available as a free app in the Mac App Store. Its latest official version is 1.4. Its latest unofficial version is 1.5 which is compatible with cocos2d-objC 3.4.9. It supports Objective-C. |
Cocos2d | Features | CocoStudio: a proprietary toolkit based on Cocos2d-x, containing UI Editor, Animation Editor, Scene Editor and Data Editor, together forming a complete system; the former two are tools mainly for artists while the latter are two mainly for designers. This is a proprietary project developed by Chukong Technologies. Its latest version is 3.10 which is compatible with cocos2d-X 3.10. It supports C++. In April 2016 it was deprecated and replaced with Cocos Creator. |
Cocos2d | Features | Current support Cocos Creator, which is a proprietary unified game development tool for Cocos2d-X. As of August 2017, it supports JavaScript and TypeScript only and does not support C++ nor Lua. It was based on the free Fireball-X. A C++ and Lua support for creator is under alpha-stage development since April 2017.
SpriteBuilderX, a free scene editor for Cocos2d-X with C++ support and runs on macOS only.
X-Studio, a proprietary scene editor for Cocos2d-X with Lua support and runs on Windows only.
CCProjectGenerator: a project generator for Cocos2d-ObjC 3.5 that generates Swift or Objective-C projects for Xcode. |
Cocos2d | History | Cocos2d (Python) February 2008, in the village of Los Cocos, near Córdoba, Argentina, Ricardo Quesada, a game developer, and Lucio Torre created a 2D game engine for Python with several of their developer friends. They named it "Los Cocos" after its birthplace. A month later, the group released the version 0.1 and changed its name to "Cocos2d".
Cocos2d-iPhone Attracted by the potential of the new Apple App Store for the iPhone, Quesada rewrote Cocos2d in Objective-C and in June 2008 released "Cocos2d for iPhone" v0.1, the predecessor of the later Cocos2d family.Cocos2D-ObjC (formerly known as Cocos2D-iPhone and Cocos2D-SpriteBuilder), is maintained by Lars Birkemose.
Also, the English designer Michael Heald designed a new logo for Cocos2d (the Cocos2d logo was previously a running coconut).
Cocos2d-x November 2010, a developer from China named Zhe Wang branched Cocos2d-x based on Cocos2d. Cocos2d-x is also a free engine under MIT License, and it allows for compiling and running on multiple platforms with one code base.
In 2013, Quesada left cocos2d-iPhone and joined in cocos2d-x team. In March 2017, Quesada was laid off from the Chukong company. In 2015, there are 4 cocos2d branches being actively maintained.
Cocos2d-x & Cocos2d-html5 is maintained and sponsored by developers at Chukong Technologies. Chukong is also developing CocoStudio, which is a WYSIWYG editor for Cocos2d-x and Cocos2D-html5, and a free Cocos3d-x fork of the Cocos3D project. |
Cocos2d | History | Other ports, forks, and bindings Cocos2d has been ported into various programming languages and to all kinds of platforms. Among them there are: ShinyCocos, in Ruby Cocos2d-Android, in Java for Android Cocos2d-windows, in C++ for Windows XP and Windows 7 CocosNet, in C# based on Mono Cocos2d-javascript, in JavaScript for web browsers Cocos2d-XNA was born in cocos2d-x community for supporting Windows Phone 7, but now it's branched to an independent project using C# and mono to run on multiple platforms. Jacob Anderson at Totally Evil Entertainment is leading this branch. |
Cocos2d | History | Cocos3d works as an extension on cocos2d-iPhone, written in Objective-C. Bill Hollings at Brenwill Workshop Ltd is leading this branch. |
Cocos2d | Games developed with cocos2d | FarmVille Plague Inc.
Geometry Dash (cocos2d-x) Miitomo (cocos2d-x) Badland (cocos2d-iphone) Shadow Fight 2 (cocos2d-x) Cookie Run: OvenBreak Fire Emblem Heroes |
Chronicle Security | Chronicle Security | Chronicle Security is a cybersecurity company which is part of the Google Cloud Platform. Chronicle is a cloud service, built as a specialized layer on top of core Google infrastructure, designed for enterprises to privately retain, analyze, and search the massive amounts of security and network telemetry they generate. The company began as a product by X, but became its own company in January 2018. Chronicle creates tools for businesses to prevent cybercrime on their platforms. Chronicle announced "Backstory" at RSA 2019 in March, adding log capture and analysis to the family of products that include VirusTotal, and UpperCase which provide threat intelligence (Known Malicious IPs and URLs). Backstory claims to "Extract signals from your security telemetry to find threats instantly," by combining log data with threat intelligence. |
Chronicle Security | Chronicle Security | In June 2019 Thomas Kurian announced that Chronicle would be merged into Google Cloud.Backstory and VirusTotal are now offered to Google Cloud customers as part of an Autonomic Security Operations solution that also includes Looker and BigQuery. |
Call Taxi (India) | Call Taxi (India) | Call Taxis are taxi services in India in several cities in India. |
Call Taxi (India) | Call Taxi (India) | In some cities, they operate under a regular taxi permit, while in some cities, they are treated as tourist vehicles for hire. They often offer services at all times of the day.Call Taxi services are not officially recognised by the Motor Vehicles Act.They are preferred as they are considered safer, more convenient than ordinary taxis or autorickshaws, and reliable.In Mumbai, ordinary taxicabs can be booked over the internet or with a phone. In Coimbatore, a service was launched where autorickshaws can be booked over the phone. |
Call Taxi (India) | History | Call Taxis first appeared in Chennai and were described as 'no nonsense' in comparison to regular taxicabs.
In Bangalore, Call taxis gained prominence after the opening of the Information Technology sectors.In 2013, Uber commenced operations in India. The number of Uber drivers has been growing steadily over the past few years. As the company has gained in popularity, more and more drivers are applying to drive for Uber, and driver sign ups have soared. |
HD 102776 | HD 102776 | HD 102776, also known by its Bayer designation j Centauri, is a suspected astrometric binary star system in the southern constellation of Centaurus. It has a blue-white hue and is faintly visible to the naked eye with a typical apparent visual magnitude of 4.30. The distance to this star is approximately 600 light years based on parallax, and it is drifting further away with a radial velocity of ~29 km/s. It is a member of the Lower Centaurus Crux subgroup of the Sco OB2 association. HD 102776 has a relatively large peculiar velocity of 31.1 km/s and is a candidate runaway star that was ejected from its association, most likely by a supernova explosion.The stellar classification of the visible component is B3V, matching a B-type main-sequence star. It is around 32 million years old and is spinning rapidly with estimates of its projected rotational velocity ranging from 200 up to 270 km, giving it an equatorial bulge that is up to 11% larger than the polar radius. This is a Be star showing emission features in its Balmer lines due to a circumstellar disk of decreated gas. It is classified as a suspected Gamma Cassiopeiae type variable star with a visual magnitude varying from +4.30 down to +4.39. |
Whitebait | Whitebait | Whitebait is a collective term for the immature fry of fish, typically between 25 and 50 millimetres (1 and 2 in) long. Such young fish often travel together in schools along coasts, and move into estuaries and sometimes up rivers where they can be easily caught using fine-meshed fishing nets. Whitebaiting is the activity of catching whitebait.
Individual whitebait are tender and edible, and are considered a delicacy in New Zealand. The entire fish is eaten - including head, fins, bones, and bowels. Some species make better eating than others, and the particular species that are marketed as "whitebait" vary in different parts of the world.
As whitebait consists of immature fry of many important food species (such as herring, sprat, sardines, mackerel, bass and many others) it is not an ecologically viable foodstuff and several countries impose strict controls on harvesting. |
Whitebait | Whitebait by region | Alboran Sea The Alboran Sea is the westernmost element of the Mediterranean Sea. Whitebait have been consumed as a favoured element of the diet of peoples living along the northern coasts of the Alboran Sea in Spain, even though sale of these products has been banned.
Australia In Australia whitebait refers to the juvenile stage of several predominantly galaxias species during their return to freshwater from the marine phase of their lifecycle.
Species referred to as whitebait in Australia include Common galaxias G. maculatus, Climbing galaxias G. brevipinnis, Spotted galaxias G. truttaceus, Tasmanian whitebait Lovettia sealii, Tasmanian mudfish Neochanna cleaveri, and Tasmanian smelt Retropinna tasmanica.
Whitebait were once subject to a substantial commercial fishery but today only recreational fishers are permitted to gather them, under strict conditions and for a limited season.
China Chinese whitebait is raised in fish farms and plentiful quantities are produced for export. The Chinese whitebait is larger than the New Zealand whitebait and not nearly so delicate. The frozen product is commonly available in food stores and supermarkets at reasonable prices. The Chinese name for these is often translated as "silver fish" in English.
Italy Gianchetti (also bianchetti) are the whitebait of the pesce azzurro of the Mediterranean (sardines and anchovies, etc.), caught with special nets named from the Ligurian sciabegottu (similar to the net to sciabica, but with smaller dimensions) in the early months of the year. |
Whitebait | Whitebait by region | A speciality of the Liguria cuisine, gianchetti are generally lightly boiled in salted water and served hot, dressed with oil and lemon juice. Another classic approach is to make fritters of the fish together with an egg and flour batter; finally they may simply be dipped in flour and deep fried (Frittelle di Gianchetti/Bianchetti). The gianchetti of a red colour (ruscetti, rossetti) are tougher and scaly to the palate: they are largely used to flavour fish-based sauces. |
Whitebait | Whitebait by region | In Sicilian cuisine whitebait are known as ceruses (literally translated as "baby"). Whitebait are the principal ingredient of the Sicilian specialty croquette polpette di neonata; which are a type of rolled meatball of whitebait with parsley, and egg and/or a bit of flour to amalgamate, fried in olive oil or sometimes deep-fried in peanut oil.
In Neapolitan cuisine whitebait are known as cicenielli.
In Brindisian cuisine whitebait are known as chuma (literally foam of sea). |
Whitebait | Whitebait by region | Japan In Japan, the whitebait (しらす/白子, shirasu) fishing industry is concentrated in Shizuoka Prefecture, where the major landing ports for them are situated. The shirasu boiled in salted hot water is called kamaage shirasu (釜上げしらす, boiled whitebait), and this product retains about 85% or greater water ratio.The boiled whitefish which are subsequently semi-dried are referred to generally as shirasuboshi (しらす干し, literally 'dried whitebait'), but this is in the wider sense of the term; in the stricter sense shirasuboshi (aka Kantō boshi, or 'Eastern Japan style dried') refers to soft-dried products (50–85% water ratio), and distinguished from chirimen-jako (縮緬雑魚) (aka Kansai boshi or 'Western Japan style dried') which are dried to harder consistency (30% to shy of 50% water content.)The whitebait used in these shirasu products is generally the larvae of the Japanese anchovy, but in the vernacular Japanese language anchovy (片口鰯, katakuchi iwashi) is called a type of sardine (鰯, iwashi), thus shirasu may be (somewhat misleadingly) described as sardine fry in some literature, though the larvae of clupeids do occur as bycatch in the shirasu being harvested. The shirasu landed in Shizuoka Prefecture consists of the 2–3 month old, and 1–2 cm length larvae of mostly Japanese anchovy, and a small proportion of Japanese pilchard (真鰯, ma iwashi), Sardinops sagax melanostictus, a subspecies of sardine.One specialty product is the tatami iwashi (たたみいわし, literally 'tatami sardine'), a paper-thin square wafer made from uncooked dry shirasu, spreading the washed fish thinly inside square molds then drying them, which has become a pricey delicacy. |
Whitebait | Whitebait by region | New Zealand New Zealand whitebait are the juveniles of five galaxiid species which live as adults in freshwater rivers and streams. Four of these five species have been classified by the Department of Conservation as endangered. The whitebait are caught during their migration into freshwater habitats after their larval stage at sea. They are much smaller than Chinese or British whitebait, averaging 45–55 mm in length and are around 15–22 weeks old. |
Whitebait | Whitebait by region | The most common whitebait species in New Zealand is the common galaxias or īnanga, which lays its eggs during the very high spring tides in autumn amongst bankside grasses that are flooded by the tide. The eggs develop out of the water until inundated by the next spring tide which stimulates the eggs to hatch. The larvae are then carried to sea on the outgoing tide where they join the ocean's plankton. After approximately six months, the juvenile fish migrate back into freshwater habitats where they mature to adulthood. The four other galaxiid species in New Zealand whitebait are the kōaro, banded kōkopu, giant kōkopu and shortjaw kōkopu. These species also spawn in bankside vegetation, but their spawning is triggered by autumn floods rather than tides.New Zealand whitebait are caught in the lower reaches of the rivers using large, open-mouthed, hand-held scoop nets, long sock nets, or rigid, typically wedge-shaped set nets. Whitebaiters must constantly attend the nets in order to lift them as soon as a shoal enters the net, otherwise the whitebait quickly swim back out of the net. Whitebaiters may fish from platforms known as a 'stand', which may include screens to direct the fish and systems for raising and lowering nets. |
Whitebait | Whitebait by region | Whitebaiting in New Zealand is a seasonal activity with a legally fixed and limited period which spans part of the annual migration. The timing of the allowed fishing season is set to target the more common inanga, while avoiding the less common species that mainly migrate before and after the whitebaiting season. There is strict control over net sizes and rules against blocking the river or channelling the fish into the net to allow some fish to reach the adult habitats. The whitebait themselves are very sensitive to objects in the river and are adept at dodging the nets. |
Whitebait | Whitebait by region | Whitebait is a traditional food for Māori, and was widely eaten by European settlers in the 19th Century. By the 20th Century, the price of whitebait rose and it became known as a delicacy. Currently, it commands high prices to the extent that it is the most expensive fish on the market, when available. The wholesale price (NZD) is typically $60–$70 per kilogram ($27–$32/lb), but the retail price can be up to $140 per kilogram ($64/lb). It is normally sold fresh in small quantities, although some are frozen to extend the sale period. Nevertheless, whitebait can normally only be purchased during or close after the netting season. The most popular way of cooking whitebait in New Zealand is the whitebait fritter, which is essentially an omelette containing whitebait. Purists use only the egg white in order to minimise interfering with the taste of the bait.The degradation of waterways through forest clearance, and the impacts of agriculture and urbanisation, have caused the whitebait catch to decline. The loss of suitable spawning habitat has been particularly severe, especially for inanga, which rely on dense riparian vegetation lining the tidal portions of waterways. Amongst other factors, a lack of shade over waterways has been shown to kill developing whitebait eggs. |
Whitebait | Whitebait by region | United Kingdom In the United Kingdom today, whitebait principally refers to the fry of Clupeidae fish, young sprats, most commonly herring. They are normally deep-fried, coated in flour or a light batter, and served very hot with sprinkled lemon juice and bread and butter. Whitebait are very hard to buy fresh unless the buyer goes to a fishing harbour early in the morning, as most are frozen on the boat. |
Whitebait | Whitebait by region | Records of whitebait as a food in England date back to 1612. By the 1780s it was fashionable to dine on whitebait. In those days, whitebait was thought to be a species or group on its own right, and the French zoologist Valenciennes proposed that whitebait was a new genus, which he called Rogenia. In 1903, Dr James Murie, in his 'Report on the sea fisheries and fishing industry of the Thames estuary' conducted studies on the contents of boxes sold as whitebait. He discovered that some boxes of whitebait contained up to 23 species of immature fish, including the fry of eel, plaice, whiting, herring sprat and bass, along with shrimp, crab, octopus and even jellyfish. |
Whitebait | Whitebait by region | For Londoners in the 19th century and before, summer excursions down the Thames to Greenwich or Blackwall to dine on whitebait were popular. For instance, the Cabinet undertook such a trip every year shortly before the prorogation of Parliament. An annual whitebait festival takes place in Southend.Given that UK and imported whitebait still consists of immature herring, sprat, sardines, mackerel, bass and many others, it is not an ecologically viable foodstuff. Removing these fish at such a juvenile stage, before they have had a chance to grow and reproduce, might severely reduce future fish stocks. The Marine Conservation Society (MCS) is a non-government organisation that provides independent information on the sustainability of fish stocks and species around the world, and has a rating system for fish sustainability, in order to safeguard future stocks. The MCS suggests avoiding eating and purchasing the juvenile whitebait as it is detrimental to sustainable fish populations. |
Whitebait | Whitebait by region | Puerto Rico Residents of Arecibo, Puerto Rico traditionally fish for whitebait at the mouth of the Río Grande de Arecibo. The fish are known locally as cetí and classified as Pellona bleekeriana or Sicydium plumieri. |
Whitebait | Elvers | Elvers are young eels. Traditionally, fishermen consumed elvers as a cheap dish, but environmental changes have reduced eel populations. Similar to whitebait, they are now considered a delicacy and are priced at up to 1000 euro per kilogram. |
Whitebait | Cuttlefish, octopus and squid | Battered and fried baby cephalopods (usually cuttlefish, but sometimes squid or octopus), known as puntillitas or chopitos, are popular in southern Spain and the Balearic Islands and possibly elsewhere. |
Distributed Interactive Simulation | Distributed Interactive Simulation | Distributed Interactive Simulation (DIS) is an IEEE standard for conducting real-time platform-level wargaming across multiple host computers and is used worldwide, especially by military organizations but also by other agencies such as those involved in space exploration and medicine. |
Distributed Interactive Simulation | History | The standard was developed over a series of "DIS Workshops" at the Interactive Networked Simulation for Training symposium, held by the University of Central Florida's Institute for Simulation and Training (IST). The standard itself is very closely patterned after the original SIMNET distributed interactive simulation protocol, developed by Bolt, Beranek and Newman (BBN) for Defense Advanced Research Project Agency (DARPA) in the early through late 1980s. BBN introduced the concept of dead reckoning to efficiently transmit the state of battle field entities. |
Distributed Interactive Simulation | History | In the early 1990s, IST was contracted by the United States Defense Advanced Research Project Agency to undertake research in support of the US Army Simulator Network (SimNet) program. Funding and research interest for DIS standards development decreased following the proposal and promulgation of its successor, the High Level Architecture (simulation) (HLA) in 1996. HLA was produced by the merger of the DIS protocol with the Aggregate Level Simulation Protocol (ALSP) designed by MITRE. |
Distributed Interactive Simulation | History | There was a NATO standardisation agreement (STANAG 4482, Standardised Information Technology Protocols for Distributed Interactive Simulation (DIS), adopted in 1995) on DIS for modelling and simulation interoperability. This was retired in favour of HLA in 1998 and officially cancelled in 2010 by the NATO Standardization Agency (NSA). |
Distributed Interactive Simulation | The DIS family of standards | DIS is defined under IEEE Standard 1278: IEEE 1278-1993 - Standard for Distributed Interactive Simulation - Application protocols IEEE 1278.1-1995 - Standard for Distributed Interactive Simulation - Application protocols IEEE 1278.1-1995 - Standard for Distributed Interactive Simulation - Application protocols (Corrections) IEEE 1278.1A-1998 - Standard for Distributed Interactive Simulation - Application protocols Errata (May 1998) IEEE 1278.1-2012 - Standard for Distributed Interactive Simulation - Application protocols IEEE-1278.2-1995 - Standard for Distributed Interactive Simulation - Communication Services and Profiles IEEE 1278.3-1996 - Recommended Practice for Distributed Interactive Simulation - Exercise Management and Feedback IEEE 1278.4-1997 - Recommended Practice for Distributed Interactive - Verification Validation & Accreditation IEEE P1278.5-XXXX - Fidelity Description Requirements (never published)In addition to the IEEE standards, the Simulation Interoperability Standards Organization (SISO) maintains and publishes an "enumerations and bit encoded fields" document yearly. This document is referenced by the IEEE standards and used by DIS, TENA and HLA federations. Both PDF and XML versions are available. |
Distributed Interactive Simulation | Current status | SISO, a sponsor committee of the IEEE, promulgates improvements in DIS. Major changes occurred in the DIS 7 update to IEEE 1278.1 to make DIS more extensible, efficient and to support the simulation of more real world capabilities. |
Distributed Interactive Simulation | Application protocol | Simulation state information is encoded in formatted messages, known as protocol data units (PDUs) and exchanged between hosts using existing transport layer protocols, including multicast, though broadcast User Datagram Protocol is also supported. There are several versions of the DIS application protocol, not only including the formal standards, but also drafts submitted during the standards balloting process. |
Distributed Interactive Simulation | Application protocol | Version 1 - Standard for Distributed Interactive Simulation - Application Protocols, Version 1.0 Draft (1992) Version 2 - IEEE 1278-1993 Version 3 - Standard for Distributed Interactive Simulation - Application Protocols, Version 2.0 Third Draft (May 1993) Version 4 - Standard for Distributed Interactive Simulation - Application Protocols, Version 2.0 Fourth Draft (March 1994) Version 5 - IEEE 1278.1-1995 Version 6 - IEEE 1278.1a-1998 (amendment to IEEE 1278.1-1995) Version 7 - IEEE 1278.1-2012 (See External Link - DIS Product Development Group.) Version 7 is also called DIS 7. This is a major upgrade to DIS to enhance extensibility and flexibility. It provides extensive clarification and more details of requirements, and adds some higher-fidelity mission capabilities. |
Distributed Interactive Simulation | Protocol data units | The current version (DIS 7) defines 72 different PDU types, arranged into 13 families. Frequently used PDU types are listed below for each family. PDU and family names shown in italics are found in DIS 7. |
Distributed Interactive Simulation | Protocol data units | Entity information/interaction family - Entity State, Collision, Collision-Elastic, Entity State Update, Attribute Warfare family - Fire, Detonation, Directed Energy Fire, Entity Damage Status Logistics family - Service Request, Resupply Offer, Resupply Received, Resupply Cancel, Repair Complete, Repair Response Simulation management family - Start/Resume, Stop/Freeze, Acknowledge Distributed emission regeneration family - Designator, Electromagnetic Emission, IFF/ATC/NAVAIDS, Underwater Acoustic, Supplemental Emission/Entity State (SEES) Radio communications family - Transmitter, Signal, Receiver, Intercom Signal, Intercom Control Entity management family Minefield family Synthetic environment family Simulation management with reliability family Live entity family Non-real time family Information Operations family - Information Operations Action, Information Operations Report |
Distributed Interactive Simulation | Realtime Platform Reference FOM (RPR FOM) | The RPR FOM is a Federation Object Model (FOM) for the High-Level Architecture designed to organize the PDUs of DIS into an HLA object class and interaction class hierarchy. It has been developed as the SISO standard SISO-STD-001. The purpose is to support transition of legacy DIS systems to the HLA, to enhance a priori interoperability among RPR FOM users and to support newly developed federates with similar requirements. The most recent version is RPR FOM version 2.0 that corresponds to DIS version 6. |
Prolactin-releasing hormone | Prolactin-releasing hormone | Prolactin-releasing hormone, also known as PRLH, is a hypothetical human hormone or hormone releasing factor. Existence of this factor has been hypothesized as prolactin is the only currently known hormone for which almost exclusively negative regulating factors are known (such as dopamine, leukemia inhibitory factor, some prostaglandins) but few stimulating factor. Its secretion is mediated by estrogen from placenta during pregnancy to elevate blood level of prolactin . While many prolactin stimulating and enhancing factors are well known (such as thyrotropin-releasing hormone, oxytocin, vasoactive intestinal peptide and estrogen) those have primary functions other than stimulating prolactin release and the search for hypothetical releasing factor or factors continues. |
Prolactin-releasing hormone | Prolactin-releasing hormone | The prolactin-releasing peptide identified in 1998 was a candidate for this function, however as of 2008 it appears its function is not yet completely elucidated. |
Stateful firewall | Stateful firewall | In computing, a stateful firewall is a network-based firewall that individually tracks sessions of network connections traversing it. Stateful packet inspection, also referred to as dynamic packet filtering, is a security feature often used in non-commercial and business networks. |
Stateful firewall | Description | A stateful firewall keeps track of the state of network connections, such as TCP streams, UDP datagrams, and ICMP messages, and can apply labels such as LISTEN, ESTABLISHED, or CLOSING. State table entries are created for TCP streams or UDP datagrams that are allowed to communicate through the firewall in accordance with the configured security policy. Once in the table, all RELATED packets of a stored session are streamlined allowed, taking fewer CPU cycles than standard inspection. Related packets are also permitted to return through the firewall even if no rule is configured to allow communications from that host. If no traffic is seen for a specified time (implementation dependent), the connection is removed from the state table. Applications can send keepalive messages periodically to prevent a firewall from dropping the connection during periods of no activity or for applications which by design have long periods of silence. |
Stateful firewall | Description | The method of maintaining a session's state depends on the transport protocol being used. TCP is a connection oriented protocol and sessions are established with a three-way handshake using SYN packets and ended by sending a FIN notification. The firewall can use these unique connection identifiers to know when to remove a session from the state table without waiting for a timeout. UDP is a connectionless protocol, which means it does not send unique connection related identifiers while communicating. Because of that, a session will only be removed from the state table after the configured time-out. UDP hole punching is a technology that leverages this trait to allow for dynamically setting up data tunnels over the internet. ICMP messages are distinct from TCP and UDP and communicate control information of the network itself. A well known example of this is the ping utility. ICMP responses will be allowed back through the firewall. In some scenarios, UDP communication can use ICMP to provide information about the state of the session so ICMP responses related to a UDP session will also be allowed back through. |
Stateful firewall | Description | Stateful inspection firewall advantages Monitors the entire session for the state of the connection, while also checking IP addresses and payloads for more thorough security Offers a high degree of control over what content is let in or out of the network Does not need to open numerous ports to allow traffic in or out Delivers substantive logging capabilities Stateful inspection firewall disadvantages Resource-intensive and interferes with the speed of network communications More expensive than other firewall options Doesn't provide authentication capabilities to validate traffic sources are not spoofed Doesn't work with asymmetric routing (opposite directions use different paths) |
Applied mathematics | Applied mathematics | Applied mathematics is the application of mathematical methods by different fields such as physics, engineering, medicine, biology, finance, business, computer science, and industry. Thus, applied mathematics is a combination of mathematical science and specialized knowledge. The term "applied mathematics" also describes the professional specialty in which mathematicians work on practical problems by formulating and studying mathematical models.
In the past, practical applications have motivated the development of mathematical theories, which then became the subject of study in pure mathematics where abstract concepts are studied for their own sake. The activity of applied mathematics is thus intimately connected with research in pure mathematics. |
Applied mathematics | History | Historically, applied mathematics consisted principally of applied analysis, most notably differential equations; approximation theory (broadly construed, to include representations, asymptotic methods, variational methods, and numerical analysis); and applied probability. These areas of mathematics related directly to the development of Newtonian physics, and in fact, the distinction between mathematicians and physicists was not sharply drawn before the mid-19th century. This history left a pedagogical legacy in the United States: until the early 20th century, subjects such as classical mechanics were often taught in applied mathematics departments at American universities rather than in physics departments, and fluid mechanics may still be taught in applied mathematics departments. Engineering and computer science departments have traditionally made use of applied mathematics. |
Applied mathematics | Divisions | Today, the term "applied mathematics" is used in a broader sense. It includes the classical areas noted above as well as other areas that have become increasingly important in applications. Even fields such as number theory that are part of pure mathematics are now important in applications (such as cryptography), though they are not generally considered to be part of the field of applied mathematics per se. |
Applied mathematics | Divisions | There is no consensus as to what the various branches of applied mathematics are. Such categorizations are made difficult by the way mathematics and science change over time, and also by the way universities organize departments, courses, and degrees. |
Applied mathematics | Divisions | Many mathematicians distinguish between "applied mathematics", which is concerned with mathematical methods, and the "applications of mathematics" within science and engineering. A biologist using a population model and applying known mathematics would not be doing applied mathematics, but rather using it; however, mathematical biologists have posed problems that have stimulated the growth of pure mathematics. Mathematicians such as Poincaré and Arnold deny the existence of "applied mathematics" and claim that there are only "applications of mathematics." Similarly, non-mathematicians blend applied mathematics and applications of mathematics. The use and development of mathematics to solve industrial problems is also called "industrial mathematics".The success of modern numerical mathematical methods and software has led to the emergence of computational mathematics, computational science, and computational engineering, which use high-performance computing for the simulation of phenomena and the solution of problems in the sciences and engineering. These are often considered interdisciplinary. |
Applied mathematics | Divisions | Applicable mathematics Sometimes, the term applicable mathematics is used to distinguish between the traditional applied mathematics that developed alongside physics and the many areas of mathematics that are applicable to real-world problems today, although there is no consensus as to a precise definition.Mathematicians often distinguish between "applied mathematics" on the one hand, and the "applications of mathematics" or "applicable mathematics" both within and outside of science and engineering, on the other. Some mathematicians emphasize the term applicable mathematics to separate or delineate the traditional applied areas from new applications arising from fields that were previously seen as pure mathematics. For example, from this viewpoint, an ecologist or geographer using population models and applying known mathematics would not be doing applied, but rather applicable, mathematics. Even fields such as number theory that are part of pure mathematics are now important in applications (such as cryptography), though they are not generally considered to be part of the field of applied mathematics per se. Such descriptions can lead to applicable mathematics being seen as a collection of mathematical methods such as real analysis, linear algebra, mathematical modelling, optimisation, combinatorics, probability and statistics, which are useful in areas outside traditional mathematics and not specific to mathematical physics. |
Applied mathematics | Divisions | Other authors prefer describing applicable mathematics as a union of "new" mathematical applications with the traditional fields of applied mathematics. With this outlook, the terms applied mathematics and applicable mathematics are thus interchangeable. |
Applied mathematics | Utility | Historically, mathematics was most important in the natural sciences and engineering. However, since World War II, fields outside the physical sciences have spawned the creation of new areas of mathematics, such as game theory and social choice theory, which grew out of economic considerations. Further, the utilization and development of mathematical methods expanded into other areas leading to the creation of new fields such as mathematical finance and data science. |
Applied mathematics | Utility | The advent of the computer has enabled new applications: studying and using the new computer technology itself (computer science) to study problems arising in other areas of science (computational science) as well as the mathematics of computation (for example, theoretical computer science, computer algebra, numerical analysis). Statistics is probably the most widespread mathematical science used in the social sciences. |
Applied mathematics | Status in academic departments | Academic institutions are not consistent in the way they group and label courses, programs, and degrees in applied mathematics. At some schools, there is a single mathematics department, whereas others have separate departments for Applied Mathematics and (Pure) Mathematics. It is very common for Statistics departments to be separated at schools with graduate programs, but many undergraduate-only institutions include statistics under the mathematics department. |
Applied mathematics | Status in academic departments | Many applied mathematics programs (as opposed to departments) consist primarily of cross-listed courses and jointly appointed faculty in departments representing applications. Some Ph.D. programs in applied mathematics require little or no coursework outside mathematics, while others require substantial coursework in a specific area of application. In some respects this difference reflects the distinction between "application of mathematics" and "applied mathematics". |
Applied mathematics | Status in academic departments | Some universities in the U.K. host departments of Applied Mathematics and Theoretical Physics, but it is now much less common to have separate departments of pure and applied mathematics. A notable exception to this is the Department of Applied Mathematics and Theoretical Physics at the University of Cambridge, housing the Lucasian Professor of Mathematics whose past holders include Isaac Newton, Charles Babbage, James Lighthill, Paul Dirac, and Stephen Hawking. |
Applied mathematics | Status in academic departments | Schools with separate applied mathematics departments range from Brown University, which has a large Division of Applied Mathematics that offers degrees through the doctorate, to Santa Clara University, which offers only the M.S. in applied mathematics. Research universities dividing their mathematics department into pure and applied sections include MIT. Students in this program also learn another skill (computer science, engineering, physics, pure math, etc.) to supplement their applied math skills. |
Applied mathematics | Associated mathematical sciences | Applied mathematics is associated with the following mathematical sciences: Engineering and technological engineering With applications of applied geometry together with applied chemistry.
Scientific computing Scientific computing includes applied mathematics (especially numerical analysis), computing science (especially high-performance computing), and mathematical modelling in a scientific discipline.
Computer science Computer science relies on logic, algebra, discrete mathematics such as graph theory, and combinatorics.
Operations research and management science Operations research and management science are often taught in faculties of engineering, business, and public policy. |
Applied mathematics | Associated mathematical sciences | Statistics Applied mathematics has substantial overlap with the discipline of statistics. Statistical theorists study and improve statistical procedures with mathematics, and statistical research often raises mathematical questions. Statistical theory relies on probability and decision theory, and makes extensive use of scientific computing, analysis, and optimization; for the design of experiments, statisticians use algebra and combinatorial design. Applied mathematicians and statisticians often work in a department of mathematical sciences (particularly at colleges and small universities). |
Applied mathematics | Associated mathematical sciences | Actuarial science Actuarial science applies probability, statistics, and economic theory to assess risk in insurance, finance and other industries and professions. |
Applied mathematics | Associated mathematical sciences | Mathematical economics Mathematical economics is the application of mathematical methods to represent theories and analyze problems in economics. The applied methods usually refer to nontrivial mathematical techniques or approaches. Mathematical economics is based on statistics, probability, mathematical programming (as well as other computational methods), operations research, game theory, and some methods from mathematical analysis. In this regard, it resembles (but is distinct from) financial mathematics, another part of applied mathematics.According to the Mathematics Subject Classification (MSC), mathematical economics falls into the Applied mathematics/other classification of category 91: Game theory, economics, social and behavioral scienceswith MSC2010 classifications for 'Game theory' at codes 91Axx and for 'Mathematical economics' at codes 91Bxx. |
Applied mathematics | Associated mathematical sciences | Other disciplines The line between applied mathematics and specific areas of application is often blurred. Many universities teach mathematical and statistical courses outside the respective departments, in departments and areas including business, engineering, physics, chemistry, psychology, biology, computer science, scientific computation, information theory, and mathematical physics. |
Cochlear nucleus | Cochlear nucleus | The cochlear nuclear (CN) complex comprises two cranial nerve nuclei in the human brainstem, the ventral cochlear nucleus (VCN) and the dorsal cochlear nucleus (DCN). The ventral cochlear nucleus is unlayered whereas the dorsal cochlear nucleus is layered. Auditory nerve fibers, fibers that travel through the auditory nerve (also known as the cochlear nerve or eighth cranial nerve) carry information from the inner ear, the cochlea, on the same side of the head, to the nerve root in the ventral cochlear nucleus. At the nerve root the fibers branch to innervate the ventral cochlear nucleus and the deep layer of the dorsal cochlear nucleus. All acoustic information thus enters the brain through the cochlear nuclei, where the processing of acoustic information begins. The outputs from the cochlear nuclei are received in higher regions of the auditory brainstem. |
Cochlear nucleus | Structure | The cochlear nuclei (CN) are located at the dorso-lateral side of the brainstem, spanning the junction of the pons and medulla.
The ventral cochlear nucleus (VCN) on the ventral aspect of the brain stem, ventrolateral to the inferior peduncle.
The dorsal cochlear nucleus (DCN), also known as the tuberculum acusticum or acoustic tubercle, curves over the VCN and wraps around the cerebellar peduncle.
The VCN is further divided by the nerve root into the posteroventral cochlear nucleus (PVCN) and the anteroventral cochlear nucleus (AVCN). |
Cochlear nucleus | Structure | Projections to the cochlear nuclei The major input to the cochlear nucleus is from the auditory nerve, a part of cranial nerve VIII (the vestibulocochlear nerve). The auditory nerve fibers form a highly organized system of connections according to their peripheral innervation of the cochlea. Axons from the spiral ganglion cells of the lower frequencies innervate the ventrolateral portions of the ventral cochlear nucleus and lateral-ventral portions of the dorsal cochlear nucleus. The axons from the higher frequency organ of corti hair cells project to the dorsal portion of the ventral cochlear nucleus and the dorsal-medial portions of the dorsal cochlear nucleus. The mid frequency projections end up in between the two extremes; in this way the tonotopic organization that is established in the cochlea is preserved in the cochlear nuclei. This tonotopic organization is preserved because only a few inner hair cells synapse on the dendrites of a nerve cell in the spiral ganglion, and the axon from that nerve cell synapses on only a very few dendrites in the cochlear nucleus. In contrast with the VCN that receives all acoustic input from the auditory nerve, the DCN receives input not only from the auditory nerve but it also receives acoustic input from neurons in the VCN (T stellate cells). The DCN is therefore in a sense a second order sensory nucleus. |
Cochlear nucleus | Structure | The cochlear nuclei have long been thought to receive input only from the ipsilateral ear. There is evidence, however, for stimulation from the contralateral ear via the contralateral CN, and also the somatosensory parts of the brain. |
Cochlear nucleus | Structure | Projections from the cochlear nuclei There are three major fiber bundles, axons of cochlear nuclear neurons, that carry information from the cochlear nuclei to targets that are mainly on the opposite side of the brain. Through the medulla, one projection goes to the contralateral superior olivary complex (SOC) via the trapezoid body, whilst the other half shoots to the ipsilateral SOC. This pathway is called the ventral acoustic stria (VAS or, more commonly, the trapezoid body). Another pathway, called the dorsal acoustic stria (DAS, also known as the stria of von Monakow), rises above the medulla into the pons where it hits the nuclei of the lateral lemniscus along with its kin, the intermediate acoustic stria (IAS, also known as the stria of Held). The IAS decussates across the medulla, before joining the ascending fibers in the contralateral lateral lemniscus. The lateral lemniscus contains cells of the nuclei of the lateral lemniscus, and in turn projects to the inferior colliculus. The inferior colliculus receives direct, monosynaptic projections from the superior olivary complex, the contralateral dorsal acoustic stria, some classes of stellate neurons of the VCN, as well as from the different nuclei of the lateral lemniscus. |
Cochlear nucleus | Structure | Most of these inputs terminate in the inferior colliculus, although there are a few small projections that bypass the inferior colliculus and project to the medial geniculate, or other forebrain structures.
Medial superior olive (MSO) via trapezoid body (TB) – Ipsilateral and contralateral stimulation for low frequency sounds.
Lateral superior olive (LSO) directly and via TB – Ipsilateral stimulation for high frequency sounds.
Medial nucleus of trapezoid body (MNTB) – Contralateral stimulation.
Inferior colliculus – Contralateral stimulation.
Periolivary nuclei (PON) – Ipsilateral and contralateral stimulation.
Lateral lemniscus (LL) and lemniscal nuclei (LN) – Ipsilateral and contralateral stimulation.
Histology Three types of principal cells convey information out of the ventral cochlear nucleus: Bushy cells, stellate cells, and octopus cells. |
Cochlear nucleus | Structure | Bushy cells are found mainly in the anterior ventral cochlear nucleus (AVCN). These can be further divided into large spherical, small spherical and globular bushy cells, depending on their appearance, and also their location. Within the AVCN there is an area of large spherical cells; caudal to this are smaller spherical cells, and globular cells occupy the region around the nerve root. An important difference between these subtypes is that they project to differing targets in the superior olivary complex. Large spherical bushy cells project to the ipsilateral and contralateral medial superior olive. Globular bushy cells project to the contralateral medial nucleus of the trapezoid body, and small spherical bushy cells likely project to the lateral superior olive. They have a few (1-4) very short dendrites with numerous small branching, which cause it to resemble a “bush”. The bushy cells have specialized electrical properties that allow them to transmit timing information from the auditory nerve to more central areas of the auditory system. Because bushy cells receive input from multiple auditory nerve fibers that are tuned to similar frequencies, bushy cells can improve the precision of the timing information by in essence averaging out jitter in timing of the inputs. Bushy cells can also be inhibited by sounds adjacent to the frequency to which they are tuned, leading to even sharper tuning than seen in auditory nerve fibers. These cells are usually innervated only by a few auditory nerve fibres, which dominate its firing pattern. These afferent nerve fibres wrap their terminal branches around the entire soma, creating a large synapse onto the bushy cells, called an "endbulb of Held". Therefore, a single unit recording of an electrically stimulated bushy neuron characteristically produces exactly one action potential and constitutes the primary response. |
Cochlear nucleus | Structure | Stellate cells (aka multipolar cells), have longer dendrites that lie parallel to fascicles of auditory nerve fibers. They are also called chopper cells, in reference to their ability to fire a regularly spaced train of action potentials for the duration of a tonal or noise stimulus. The chopping pattern is intrinsic to the electrical excitability of the stellate cell, and the firing rate depends on the strength of the auditory input more than on the frequency. Each stellate cell is narrowly tuned and has inhibitory sidebands, enabling the population of stellate cells to encode the spectrum of sounds, enhancing spectral peaks and valleys. These neurons provide acoustic input to the DCN. |
Cochlear nucleus | Structure | Octopus cells are found in a small region of the posterior ventral cochlear nucleus (PVCN). The distinguishing features of these cells are their long, thick and tentacle-shaped dendrites that typically emanate from one side of the cell body. Octopus cells produce an "Onset Response" to simple tonal stimuli. That is, they respond only at the onset of a broad-band stimulus. The octopus cells can fire with some of the highest temporal precision of any neuron in the brain. Electrical stimuli to the auditory nerve evoke a graded excitatory postsynaptic potential in the octopus cells. These EPSPs are very brief. The octopus cells are thought to be important for extracting timing information. It has been reported that these cells can respond to click trains at a rate of 800 Hz.Two types of principal cells convey information out of the dorsal cochlear nucleus (DCN) to the contralateral inferior colliculus. The principal cells receive two systems of inputs. Acoustic input comes to the deep layer through several paths. Excitatory acoustic input comes from auditory nerve fibers and also from stellate cells of the VCN. Acoustic input is also conveyed through inhibitory interneurons (tuberculoventral cells of the DCN and "wide band inhibitors" in the VCN). Through the outermost molecular layer, the DCN receives other types of sensory information, most importantly information about the location of the head and ears, through parallel fibers. This information is distributed through a cerebellar like circuit that also includes inhibitory interneurons. Fusiform cells (also known as pyramidal cells). Fusiform cells integrate information through two tufts of dendrites, the apical dendrites receiving multisensory, excitatory and inhibitory input through the outermost molecular layer and the basal dendrites receiving excitatory and inhibitory acoustic input from the basal dendrites that extend into the deep layer. These neurons are thought to enable mammals to analyze the spectral cues that enable us to localize sounds in elevation and when we lose hearing in one ear. |
Cochlear nucleus | Structure | Giant cells also integrate inputs from the molecular and deep layers but input from the deep layer is predominant. It is unclear what their role is in hearing. |
Cochlear nucleus | Function | The cochlear nuclear complex is the first integrative, or processing, stage in the auditory system. Information is brought to the nuclei from the ipsilateral cochlea via the cochlear nerve. Several tasks are performed in the cochlear nuclei. By distributing acoustic input to multiple types of principal cells, the auditory pathway is subdivided into parallel ascending pathways, which can simultaneously extract different types of information. The cells of the ventral cochlear nucleus extract information that is carried by the auditory nerve in the timing of firing and in the pattern of activation of the population of auditory nerve fibers. The cells of the dorsal cochlear nucleus perform a non-linear spectral analysis and place that spectral analysis into the context of the location of the head, ears and shoulders and that separate expected, self-generated spectral cues from more interesting, unexpected spectral cues using input from the auditory cortex, pontine nuclei, trigeminal ganglion and nucleus, dorsal column nuclei and the second dorsal root ganglion. It is likely that these neurons help mammals to use spectral cues for orienting toward those sounds. The information is used by higher brainstem regions to achieve further computational objectives (such as sound source location or improvement in signal-to-noise ratio). The inputs from these other areas of the brain probably play a role in sound localization. |
Cochlear nucleus | Function | In order to understand in more detail the specific functions of the cochlear nuclei it is first necessary to understand the way sound information is represented by the fibers of the auditory nerve. Briefly, there are around 30,000 auditory nerve fibres in each of the two auditory nerves. Each fiber is an axon of a spiral ganglion cell that represents a particular frequency of sound, and a particular range of loudness. Information in each nerve fibre is represented by the rate of action potentials as well as the particular timing of individual action potentials. The particular physiology and morphology of each cochlear nucleus cell type enhances different aspects of sound information. |
Buttermilk Crispy Tenders | Buttermilk Crispy Tenders | Buttermilk Crispy Tenders (and their precursor, Chicken Selects) were chicken strips sold by the international fast food restaurant chain McDonald's in the United States and Canada. Chicken Selects were introduced in early 1998 for a limited time and offered again in early 2002 and late 2003 and then permanently starting in 2004. In the UK, they were launched on the "Pound Saver Menu", which offers various menu items for £0.99. |
Buttermilk Crispy Tenders | Buttermilk Crispy Tenders | In mid-2006, McDonald's introduced the Snack Wrap, which contains a Chicken Selects Premium Breast Strip, or as of January 2007, a Grilled Chicken Breast Strip, cheddar/jack cheese, lettuce, and either ranch, honey mustard, or chipotle barbecue sauce, all wrapped inside a white flour tortilla, priced at 99¢-$1.39 depending on the market.
Chicken Selects were terminated in 2013. The product briefly returned in 2015 as a limited-time promotion. In August 2017, a similar chicken tender product named "Buttermilk Crispy Tenders" was added to the menu. However, they were discontinued in 2020 as a result of the COVID-19 pandemic. |
Buttermilk Crispy Tenders | Composition | Ingredients for the Chicken Selects Premium Breast Strip are listed as "Chicken breast strips, water, seasoning [salt, monosodium glutamate, carrageenan gum, chicken broth, natural flavor (plant and animal source), maltodextrin, spice, autolyzed yeast extract, chicken fat, polysorbate 80], modified potato starch, and sodium phosphates. Breaded with: wheat flour, water, food starch-modified, salt, spices, leavening (baking soda, sodium aluminum phosphate, monocalcium phosphate), garlic powder, onion powder, dextrose, spice extractives, and extractives of paprika. Prepared in vegetable oil (may contain one of the following: Canola oil, corn oil, soybean oil, hydrogenated soybean oil, partially hydrogenated soybean oil, partially hydrogenated corn oil with TBHQ and citric acid added to preserve freshness), dimethylpolysiloxane added as an antifoaming agent)." |