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Soundscape ecology In fact, nests in noisy habitats had higher survival than those laid in control habitats, presumably because noisy environments hosted fewer western scrub jays which are major nest predators of other birds. Thus, anthropophony can have negative effects on local species diversity, but the species capable of coping with noise disturbance may actually benefit from the exclusion of negative species interactions in those areas. Other experiments suggest that noise pollution has the potential to affect avian mating systems by altering the strength of pair bonds. When exposed to high amplitude environmental noise in a laboratory setting, zebra finches, a monogamous species, show a decreased preference for their mated partners. Similarly, male reed buntings in quiet environments are more likely to be part of a mated pair than males in noisy locations. Such effects may ultimately result in reduced reproductive output of birds subject to high levels of environmental noise. The discipline of conservation biology has traditionally been concerned with the preservation of biodiversity and the habitats that organisms are dependent upon. However, soundscape ecology encourages biologists to consider natural soundscapes as resources worthy of conservation efforts. Soundscapes that come from relatively untrammeled habitats have value for wildlife as demonstrated by the numerous negative effects of anthropogenic noise on various species | https://en.wikipedia.org/wiki?curid=31352483 | 166,477 |
Tron: Legacy The writing staff cited "The Wizard of Oz" as a source of thematic influence for "Tron: Legacy" in writing the script, with Kitsis stating that "They both have very similar DNA, which is "Tron" really lives on, in a lot of ways, trying to get home. You're put on this world and you want to go home and what is home? That's in a lot of way inspired us." Kitsis also added that they had to include an "emotional spine to take us into the story or else it just becomes a bunch of moves or gags and stuff," eventually deciding on adding a mysterious destiny to Flynn and giving him a legendary aura - "Kevin Flynn to us was Steve Jobs and Bill Gates all wrapped up into one and John Lennon." The writers decided to create the character of Clu as an evil embodiment of "how you look back on your younger self, (...) that guy [that] thought he knew everything, but he really knew nothing." Bridges liked the idea of the dual perspectives, and contributed with the writers for the characterization of Flynn as a sanguine Zen master by suggesting them to get inspiration from various Buddhist texts. Part of the concepts emerged from a reunion the producers had with scientists from California Institute of Technology and the Jet Propulsion Laboratory to discuss concepts such as isomorphic algorithms and the digitizing of organic matter. Horowitz revealed the film would contain many light cycle battles, and asserted that the script for the scenes were "incredibly detailed," and involved an intricate collaborative process | https://en.wikipedia.org/wiki?curid=22547607 | 266,775 |
Hybrid system Indeed, without forces, one cannot properly define the bouncing ball and the model is, from a mechanical point of view, meaningless. The simplest contact model that represents the interactions between the ball and the ground, is the complementarity relation between the force and the distance (the gap) between the ball and the ground. This is written as formula_10 Such a contact model does not incorporate magnetic forces, nor gluing effects. When the complementarity relations are in, one can continue to integrate the system after the impacts have accumulated and vanished: the equilibrium of the system is well-defined as the static equilibrium of the ball on the ground, under the action of gravity compensated by the contact force formula_11. One also notices from basic convex analysis that the complementarity relation can equivalently be rewritten as the inclusion into a normal cone, so that the bouncing ball dynamics is a differential inclusion into a normal cone to a convex set. See Chapters 1, 2 and 3 in Acary-Brogliato's book cited below (Springer LNACM 35, 2008). See also the other references on non-smooth mechanics. There are approaches to automatically proving properties of hybrid systems (e.g., some of the tools mentioned below). Common techniques for proving safety of hybrid systems are computation of reachable sets, abstraction refinement, and barrier certificates. Most verification tasks are undecidable, making general verification algorithms impossible | https://en.wikipedia.org/wiki?curid=564719 | 368,817 |
Enterprise modelling They include the IDEF family of methods (ICAM, 1981) and the GRAI method by Guy Doumeingts in 1984 followed by GRAI/GIM by Doumeingts and others in 1992. These second generation of methods were activity-based methods which have been surpassed on the one hand by process-centred modelling methods developed in the 1990s such as Architecture of Integrated Information Systems (ARIS), CIMOSA and Integrated Enterprise Modeling (IEM). And on the other hand by object-oriented methods, such as Object-oriented analysis (OOA) and Object-modelling technique (OMT). An enterprise model is a representation of the structure, activities, processes, information, resources, people, behavior, goals, and constraints of a business, government, or other enterprises. Thomas Naylor (1970) defined a (simulation) model as "an attempt to describe the interrelationships among a corporation's financial, marketing, and production activities in terms of a set of mathematical and logical relationships which are programmed into the computer." These interrelationships should according to Gershefski (1971) represent in detail all aspects of the firm including "the physical operations of the company, the accounting and financial practices followed, and the response to investment in key areas" Programming the modelled relationships into the computer is not always necessary: enterprise models, under different names, have existed for centuries and were described, for example, by Adam Smith, Walter Bagehot, and many others | https://en.wikipedia.org/wiki?curid=7466964 | 491,901 |
Memory controller A few experimental memory controllers (mostly aimed at the server market where data protection is legally required) contain a second level of address translation, in addition to the first level of address translation performed by the CPU's memory management unit. Memory controllers integrated into certain Intel Core processors also provide "memory scrambling" as a feature that turns user data written to the main memory into pseudo-random patterns. Memory Scrambling (in Cryptographic Theory) is supposed to prevent forensic and reverse-engineering analysis based on DRAM data remanence by effectively rendering various types of cold boot attacks ineffective. In current practice this has not been achieved. However Memory Scrambling has only been designed to address DRAM-related electrical problems. The late 2010s Memory Scrambling Standards do not fix or prevent security issues or problems. The 2010s Memory Scrambling standards are not cryptographically secure, or necessarily open sourced or open to public revision or analysis. ASUS and Intel have their own memory scrambling standards. Currently ASUS motherboards have allowed the user to choose which memory scrambling standards to use [ASUS or Intel] or whether to turn the feature off entirely. Double data rate (DDR) memory controllers are used to drive DDR SDRAM, where data is transferred on both rising and falling edges of the system's memory clock | https://en.wikipedia.org/wiki?curid=5288134 | 401,239 |
Tipu's Tiger The grunt operates by cogs gradually raising the weighted "grunt-pipe" until it reaches a point where it slips down "to fall against its fixed lower-board or reservoir, discharging the air to form the grunting sound" Today all the sound-making functions rely on the crank-handle to power them, though Ord-Hume believes this was not originally the case. Works on the noise-making functions included those made over several decades by the famous organ-building firm Henry Willis & Sons, and Henry Willis III, who worked on the tiger in the 1950s, contributed an account to a monograph by Mildred Archer of the V&A. Ord-Hume is generally ready to exempt Willis work from his scathing comments on other drastic restorations, which "vandalism" is assumed to be by unknown earlier organ-builders. There was a detailed account of the sound-making functions in "The Penny Magazine" in 1835, whose anonymous author evidently understood "things mechanical and organs in particular". From this and Ord-Hume's own investigations, he concluded that the original operation of the man's "wail" had been intermittent, with a wail only being produced after every dozen or so grunts from the tiger above, but that at some date after 1835 the mechanism had been altered to make the wail continuous, and that the bellows for the wail had been replaced with smaller and weaker ones, and the operation of the moving arm altered | https://en.wikipedia.org/wiki?curid=1555706 | 260,262 |
National Environmental Engineering Research Institute From 1990, environmental biotechnology and genomics have emerged as useful tools for sustainable development. The Institute now deals with micro-niches, in which ‘how the DNA structure can be used as a tool to analyse and provide solutions to environmental pollution problems’ is studied. From a microscopic organism to impact assessment of the mega projects like Sethusamudram, the Institute covers all aspects of R&D in environmental science and engineering. The Institute now houses a bacterial culture bank of 1200 bacteria that have been identified sequencing the 16S rRNA genes. These are used in bioremediation as well as in bio-prospecting, The Institute has demonstrated rejuvenation of mine spoil dumpsites and continue to develop additional expertise through an integrated biotechnological approach for detoxification of degraded lands. The technology for solidification / stabilization and immobilization of arsenic bearing hazardous wastes was implemented in Zuari Industries Ltd., Goa. The Institute was involved in providing solutions to some of the pollution problems due to industrial and municipal wastewater discharge in places such as Delhi and Tirupur. The Institute is also involved in the development of analytical protocols for some of the emerging pollutants like dioxins and furans, mercury, trace contaminants besides routine analytical services in environmental monitoring | https://en.wikipedia.org/wiki?curid=16085921 | 297,112 |
Power over Ethernet LLDP allows an exchange of information between a PSE and a PD. This information is formatted in Type-length-value (TLV) format. PoE standards define TLV structures used by PSEs and PDs to signal and negotiate available power. The setup phases are as follows: The rules for this power negotiation are: Some Cisco WLAN access points and VoIP phones supported a proprietary form of PoE many years before there was an IEEE standard for delivering PoE. Cisco's original PoE implementation is not software upgradeable to the IEEE 802.3af standard. Cisco's original PoE equipment is capable of delivering up to per port. The amount of power to be delivered is negotiated between the endpoint and the Cisco switch based on a power value that was added to the Cisco proprietary Cisco Discovery Protocol (CDP). CDP is also responsible for dynamically communicating the Voice VLAN value from the Cisco switch to the Cisco VoIP Phone. Under Cisco's pre-standard scheme, the PSE (switch) will send a fast link pulse (FLP) on the transmit pair. The PD (device) connects the transmit line to the receive line via a low-pass filter. And thus the PSE gets the FLP in return. And a common mode current between pair 1 and 2 will be provided resulting in and default of allocated power. The PD has then to provide Ethernet link within to the auto-negotiation mode switch port. A later CDP message with a type-length-value tells the PSE its final power requirement. A discontinuation of link pulses shuts down power | https://en.wikipedia.org/wiki?curid=782836 | 388,982 |
Museum of Transport and Technology A BAC Strikemaster may join the collection from the RNZAF. There is also a military section which restores and demonstrates a selection of Second World War military trucks, light tracked vehicles and tanks of Allied forces. The military section has regular open days when the Military Reenactment Society displays and demonstrates the vehicles and uniforms. MOTAT 2 also has an operational railway with 1 km of track, stations and a selection of former New Zealand Government Railways, light industrial locomotives, wagons and carriages. On 9 September 2011 a new and larger display hangar was opened at MOTAT 2. The existing blister hangar was moved and restored as part of the same project. With the construction of the new hangar it was now possible to display the restored De Havilland Mosquito and Lockheed Hudson. Short S25 Sunderland Mk V and NAC DC3 Dakota were in moved inside as their overhauls and external painting was completed towards the end of summer 2012. The Short S45A Solent Mk 4, Ventura and top dressing Lodestar will be housed in due course as restorations and building provisions allow. MOTAT features several major collections of transport vehicles: Tramlines on sleepered track set under bitumen were laid within the museum boundaries with trams commencing operation on 16 December 1967. The Museum tramline was later extended beyond the Museum grounds along Gt. North Road and opened on 19 December 1980 | https://en.wikipedia.org/wiki?curid=2425087 | 302,136 |
Clearfield Trust Co. v. United States Clearfield Trust Co. v. United States, 318 U.S. 363 (1943), was a case in which the Supreme Court of the United States held that federal negotiable instruments were governed by federal law, and thus the federal court had the authority to fashion a common law rule. On April 28, 1936, the Federal Reserve Bank of Philadelphia mailed a check for $24.20, drawn on the Treasurer of the United States, to Clair Barner. The check was Barner's paycheck from the Works Progress Administration (WPA). Barner never received the check, which was stolen by an unknown party. The thief forged Barner's signature and cashed the check at the J.C. Penney department store in Clearfield, Pennsylvania, where the thief assumed the identity of Mr. Barner. J.C. Penney then turned the check over to Clearfield Trust Co. as its collection agent. Clearfield Trust Co. collected the check from the Federal Reserve Bank, knowing nothing about the forgery. On May 10, 1936, Barner informed his supervisors at the WPA that he had not received his paycheck. His complaint made its way up the chain of command, and on November 30, 1936, Barner signed an affidavit alleging that the endorsement of his name on the check was forged. Neither J.C. Penney Co. nor Clearfield Trust Co. had any notice of the forgery until January 12, 1937, when the U.S. government sent its first notice about it. The United States sent its initial request for reimbursement on August 31, 1937, and filed suit against Clearfield Trust Co | https://en.wikipedia.org/wiki?curid=4688726 | 462,490 |
Dry rot treatment The UK Court of Appeal held that the guarantee was not invalidated by this clause because the wall into which the timber was built was damp due to the nature of the construction of the building, not through any lapse in maintenance by the owners. But the clear implication of this is that if the timber had become wet because the property owners had not maintained the building properly, then the guarantee would have become void. In other words, the client is protected against the recurrence of dry rot provided that the conditions that allow dry rot to occur do not recur. Graham Coleman, a leading specialist in damp treatment and timber decay, makes the same point on his website: But then dry wood doesn't rot – so what is actually being 'guaranteed? Certainly not any chemical treatment that has been applied since it is clearly implied that if treated timber becomes damp it will rot. So what was the value of the preservative treatment? Obviously none! Guarantees are therefore of questionable value and may be difficult to enforce. However, the point will still be raised that if the fungicide treatment is really effective, it should not matter whether or not the treated timber gets wet again. If, on the other hand, a fungicide-treated piece of timber must be kept dry to stop it rotting, it cannot be much more resistant to rot than wood that has not been treated | https://en.wikipedia.org/wiki?curid=25756277 | 209,581 |
Excelan was a computer networking company founded in 1982 by Kanwal Rekhi, Inder Singh and Navindra Jain. was a manufacturer of smart Ethernet cards, until the company merged with, and was acquired by Novell in 1989. The company offered a line of Ethernet "front end processor" boards for Multibus, VMEbus, Q-Bus, Unibus, and IBM AT Bus systems. The cards were equipped with their own processor and memory, and ran TCP/IP protocol software that was downloaded onto the cards from the host system. offered software like LAN Workplace that integrated the cards into a variety of operating system environments, including many flavors of UNIX, RSX-11, VMS, and DOS. The hardware and software were sold under the "EXOS" brand. In 1987, also acquired Kinetics, a small networking company that manufactured and sold a variety of Ethernet networking products for Apple Macintosh environments, most notably an AppleTalk-to-Ethernet gateway called the FastPath. also manufactured and sold Ethernet network analyzer products, the first being the Nutcracker, followed later by the LANalyzer. | https://en.wikipedia.org/wiki?curid=24450813 | 139,105 |
X-COM: Interceptor As the missile could be destroyed for up to 1 minute after launch (after which it entered hyperspace), it requires protection from assault by enemy craft. From this mission, three possible end-game sequences are possible: The game's main screen differs from previous incarnations of the series. The majority of the panel is taken up by a view of the planetary systems in The Frontier, represented as stars. However, the player can zoom into the stars to see all planets and bases located in those systems. Ship squadrons and anomalous events are also shown in this display. Located elsewhere on the main screen are links to all the various base and resource management screens. Early missions involve the detection and interception of an enemy squadron of fighters. The player responds to this, and upon the X-Com squadron intercepting the enemy craft, the game switches to the flight simulation. In this mode, the player pilots a craft along with the wingmen previously assigned to the mission, in a similar style to "", with the goals of destroying or disabling the enemy ships. There are various mission types in the game, including disabling/destroying enemy craft, capturing certain special craft, interrupting alien trade routes, escorting convoys, and base raiding missions. The player collects points for every mission, adding to the total campaign score. Every week a short report is presented, with status, recommendations or news | https://en.wikipedia.org/wiki?curid=3686819 | 459,455 |
Desensitation In telecommunication, desensitation is the reduction of desired signal gain as a result of receiver reaction to an undesired signal. The gain reduction is generally due to overload of some portion of the receiver (e.g., the automatic gain control circuitry) resulting in suppression of the desired signal because the receiver will no longer respond linearly to incremental changes in input voltage. | https://en.wikipedia.org/wiki?curid=41019 | 206,909 |
Event cinema Recorded content complements mainstream studio content by maximising the 'downtime' that plagues the cinema industry, where screens worldwide spend a large proportion of their time in darkness and cinemas empty. Some cinema chains have targeted pensioners in particular, offering free tea and coffee for afternoon matinees of recorded opera, for example. DCPs have been useful to cinemas not yet equipped with satellite broadcasting capability and has enabled exhibitors to build their Event Cinema audience, which is not generally the 18-24 demographic that multiplexes are targeting. Event Cinema has seen a return of an older, affluent audience, previously turned off by the multiplex experience, and cinemas are starting to capitalise on this by offering waiter-serviced, high class finger food and alcoholic beverages, complete with bars and restaurants, a world away from the traditional popcorn/soft drink model; art house cinemas are increasingly marketing themselves as 'destination' venues for an evening's entertainment, somewhere to spend an entire evening, rather than just a couple of hours. As exhibition admissions have plateau'd in recent years due to the explosion in VOD, tablet and mobile content technology, this new revenue stream has been a surprise and welcome addition to the cinema industry, though the US studios have been cautious in embracing the change as yet | https://en.wikipedia.org/wiki?curid=38228585 | 286,651 |
Agricultural value chain As with all agricultural growth, two things appear essential for successful value chain development: creating the right environment for agriculture and investing in rural public goods. An enabling environment implies peace and public order, macro-economic stability, inflation under control, exchange rates based on market fundamentals rather than government allocation of foreign currency, predictable taxation that is reinvested in public goods and property rights. There is a positive correlation of agricultural growth with investment in irrigation, transport infrastructure and other technologies. Governments have a responsibility to provide essential goods and services, infrastructure, such as rural roads, and agricultural research and extension. Value chain development is often constrained by corruption, both at a high level and at the ubiquitous road blocks found in many countries, particularly in Africa. Many measures to improve value chains require collaboration between a wide range of different ministries, and this can be difficult to achieve. | https://en.wikipedia.org/wiki?curid=42043691 | 504,043 |
Speaking clock Nowadays the use of the Neiti Aika service has decreased pretty much to null and the press officer of Auria, the regional phone company of Turku, stated in an article of the "Turun Sanomat" newspaper that when the company started the service in 1938 it was used 352,310 times in its starting year compared to 1300 times in September 2006. In France, the speaking clock ("horloge parlante") has been in service since 14 February 1933. It is available on 36.99 from within France, and was formerly available from overseas by dialing +33 8.36.99.xx.xx (where x could be anything). However, since September 2011 a call placed from outside France or its territories yields only a recording indicating that the number is no longer available. In the Republic of Ireland, the speaking clock () was first offered by the Department of Posts and Telegraphs in 1970, and was reachable by dialling 1191. Switchboard operator Frances Donegan was the original voice. At its peak, it received almost three million calls a year (about 8,000 a day). It was shut down on 27 August 2018 due to lack of use. On 1 October 1930, a system was installed in the Haarlem telephone exchange (automated in 1925) which indicated the time using series of tones, with number 15290. In 1934, electronic engineer and inventor F.H. Leeuwrik built a speaking clock for the municipal telephone service of The Hague using optically recorded speech, looping on a large drum | https://en.wikipedia.org/wiki?curid=615209 | 421,419 |
Extended Validation Certificate The security requirements in the EV-certificate 2008 CPS are (except for minor differences in the legalese used to express them) practically identical to the requirements for Class 3 certificates listed in Verisign’s version 1.0 CPS from 1996. EV certificates simply roll back the clock to the approach that had already failed the first time it was tried in 1996, resetting the shifting baseline and charging 1996 prices as a side-effect. There have even been proposals for a kind of sliding-window approach to certificate value in which, as the inevitable race to the bottom cheapens the effective value of established classes of certificates, they’re regarded as less and less effective by the software that uses them… | https://en.wikipedia.org/wiki?curid=7104097 | 491,599 |
Microplastics Environmental Protection Agency (EPA) launched its "Trash-Free Waters" initiative in 2013 to prevent single-use plastic wastes from ending up in waterways and ultimately the ocean. EPA collaborates with the United Nations Environment Programme–Caribbean Environment Programme (UNEP-CEP) and the Peace Corps to reduce and also remove trash in the Caribbean Sea. EPA has also funded various projects in the San Francisco Bay Area including one that is aimed at reducing the use of single-use plastics such as disposable cups, spoons and straws, from three University of California campuses. Additionally, there are many organizations advocating action to counter microplastics and that is spreading microplastic awareness. One such group is the Florida Microplastic Awareness Project (FMAP), a group of volunteers who search for microplastics in coastal water samples. Computer modelling done by The Ocean Cleanup, a Netherlands foundation, has suggested that collecting devices placed nearer to the coasts could remove about 31% of the microplastics in the area. In addition, some bacteria have evolved to eat plastic, and some bacteria species have been genetically modified to eat (certain types of) plastics. On September 9, 2018, The Ocean Cleanup launched the world's first ocean cleanup system, 001 aka “Wilson”, which is being deployed to the Great Pacific Garbage Patch | https://en.wikipedia.org/wiki?curid=27265528 | 71,398 |
Casting (metalworking) In metalworking and jewellery making, casting is a process in which a liquid metal is somehow delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a 3-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and the metal part (the "casting") is extracted. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods. Casting processes have been known for thousands of years, and have been widely used for sculpture (especially in bronze), jewellery in precious metals, and weapons and tools. Traditional techniques include lost-wax casting (which may be further divided into centrifugal casting and vacuum assist direct pour casting), plaster mold casting and sand casting. The modern casting process is subdivided into two main categories: expendable and non-expendable casting. It is further broken down by the mold material, such as sand or metal, and pouring method, such as gravity, vacuum, or low pressure. Expendable mold casting is a generic classification that includes sand, plastic, shell, plaster, and investment (lost-wax technique) moldings. This method of mold casting involves the use of temporary, non-reusable molds. Sand casting is one of the most popular and simplest types of casting, and has been used for centuries | https://en.wikipedia.org/wiki?curid=53601 | 58,576 |
Scalability can be measured over multiple dimensions, such as: Resources fall into two broad categories: horizontal and vertical. Scaling horizontally (out/in) means adding more nodes to (or removing nodes from) a system, such as adding a new computer to a distributed software application. An example might involve scaling out from one web server to three. High-performance computing applications such as seismic analysis and biotechnology workloads scaled horizontally to support tasks that once would have required expensive supercomputers. Other workloads, such as large social networks exceed the capacity of the largest supercomputer and can only be handled by scalable systems. Exploiting this scalability requires software for efficient resource management and maintenance. Scaling vertically (up/down) means adding resources to (or removing resources from) a single node, typically involving the addition of CPUs, memory or storage to a single computer. Larger numbers of elements increases management complexity, more sophisticated programming to allocate tasks among resources and handle issues such as throughput and latency across nodes, while some applications do not scale horizontally. Note that network function virtualization defines these terms differently: scaling out/in is the ability to scale by add/remove resource instances (e.g. virtual machine), whereas scaling up/down is the ability to scale by changing allocated resources (e.g | https://en.wikipedia.org/wiki?curid=185529 | 138,300 |
PLATO (computer system) Clarke Porter and PLATO veteran Jim Ghesquiere, in cooperation with NASD executive Frank McAuliffe, developed the first "on-demand" proctored commercial testing service. The testing business grew slowly and was ultimately spun off from CDC as Drake Training and Technologies in 1990. Applying many of the PLATO concepts used in the late 1970s, E. Clarke Porter led the Drake Training and Technologies testing business (today Thomson Prometric) in partnership with Novell, Inc. away from the mainframe model to a LAN-based client server architecture and changed the business model to deploy proctored testing at thousands of independent training organizations on a global scale. With the advent of a pervasive global network of testing centers and IT certification programs sponsored by, among others, Novell and Microsoft, the online testing business exploded. Pearson VUE was founded by PLATO/Prometric veterans E. Clarke Porter, Steve Nordberg and Kirk Lundeen in 1994 to further expand the global testing infrastructure. VUE improved on the business model by being one of the first commercial companies to rely on the Internet as a critical business service and by developing self-service test registration. The computer-based testing industry has continued to grow, adding professional licensure and educational testing as important business segments. A number of smaller testing-related companies also evolved from the PLATO system. One of the few survivors of that group is The Examiner Corporation. Dr | https://en.wikipedia.org/wiki?curid=1000474 | 417,603 |
Wheeling Suspension Bridge Nonetheless, navigation on the Ohio River between Wheeling and Pittsburgh remained hazardous at certain times of year (because of ice and debris in winter and spring floods, as well as summer low water). Pittsburgh and Wheeling both competed to become commercial hubs connecting east and west across the central Appalachian mountains. To the north, the Erie Canal (completed 1825 between Buffalo, New York on Lake Erie and Albany, New York on the Hudson River) and the Welland Canal (completed 1829 connecting Lake Erie and Lake Ontario bypassing Niagara Falls and creating the St. Lawrence Seaway) proved a commercial boon even to cities some distance away (especially New York City as a seaport, but also Erie, Pennsylvania). Soon, Pennsylvania competed by subsidizing first a short canal ending at Pittsburgh, then railroads connecting Pittsburgh to Philadelphia, which had rail and water connections to New York City and was a major international port in its own right. In 1835, a new incline railroad connected Pittsburgh to Ohio valley produce and goods. The combination of Pennsylvania railroads and canals became known as the "Main Line". In 1846 Pennsylvania's legislature chartered the Pennsylvania Railroad to connect its state capital Harrisburg (which had many connections to Philadelphia) with Pittsburgh | https://en.wikipedia.org/wiki?curid=1302824 | 318,481 |
Sound reinforcement system , SR systems are for live event support and PA systems are for reproduction of speech and recorded music in buildings and institutions). In some regions or markets, the distinction between the two terms is important, though the terms are considered interchangeable in many professional circles. A typical sound reinforcement system consists of; input transducers (e.g., microphones), which convert sound energy such as a person singing into an electric signal, signal processors which alter the signal characteristics (e.g., equalizers that adjust the bass and treble, compressors that reduce signal peaks, etc.), amplifiers, which produce a powerful version of the resulting signal that can drive a loudspeaker and output transducers (e.g., loudspeakers in speaker cabinets), which convert the signal back into sound energy (the sound heard by the audience and the performers). These primary parts involve varying numbers of individual components to achieve the desired goal of reinforcing and clarifying the sound to the audience, performers, or other individuals. Sound reinforcement in a large format system typically involves a signal path that starts with the signal inputs, which may be instrument pickups (on an electric guitar or electric bass) or a microphone that a vocalist is singing into or a microphone placed in front of an instrument or guitar amplifier. These signal inputs are plugged into the input jacks of a thick multicore cable (often called a "snake") | https://en.wikipedia.org/wiki?curid=764380 | 237,119 |
Heat pump Heat pumps are already at a price disadvantage when it comes to initial investment (not long-term savings) compared to conventional heating solutions like boilers, so the drive towards more efficient heat pumps and air conditioners is often led by legislative measures on minimum efficiency standards. Electricity rates will also influence the attractiveness of heat pumps. In cooling mode, a heat pump's operating performance is described in the US as its energy efficiency ratio (EER) or seasonal energy efficiency ratio (SEER), and both measures have units of BTU/(h·W) (1 BTU/(h·W) = 0.293 W/W). A larger EER number indicates better performance. The manufacturer's literature should provide both a COP to describe performance in heating mode, and an EER or SEER to describe performance in cooling mode. Actual performance varies, however, and depends on many factors such as installation details, temperature differences, site elevation, and maintenance. As with any piece of equipment that depends on coils to transfer heat between air and a fluid, it is important for both the condenser and evaporator coils to be kept clean. If deposits of dust and other debris are allowed to accumulate on the coils, the efficiency of the unit (both in heating and cooling modes) will suffer. Heat pumps are more "effective" for heating than for cooling an interior space if the temperature differential is held equal | https://en.wikipedia.org/wiki?curid=68316 | 234,344 |
White hat (computer security) They provided several specific examples of how this information could be gathered and exploited to gain control of the target, and how such an attack could be prevented. They gathered up all the tools they had used during their work, packaged them in a single, easy-to-use application, and gave it away to anyone who chose to download it. Their program, called Security Administrator Tool for Analyzing Networks, or SATAN, was met with a great amount of media attention around the world in 1992. While penetration testing concentrates on attacking software and computer systems from the start – scanning ports, examining known defects in protocols and applications running on the system and patch installations, for example – ethical hacking may include other things. A full-blown ethical hack might include emailing staff to ask for password details, rummaging through executive's dustbins and usually breaking and entering, without the knowledge and consent of the targets. Only the owners, CEOs and Board Members (stake holders) who asked for such a security review of this magnitude are aware. To try to replicate some of the destructive techniques a real attack might employ, ethical hackers may arrange for cloned test systems, or organize a hack late at night while systems are less critical. In most recent cases these hacks perpetuate for the long-term con (days, if not weeks, of long-term human infiltration into an organization) | https://en.wikipedia.org/wiki?curid=907240 | 453,812 |
Advanced composite materials (engineering) " Catalysts, inhibitors, flame retardants, and other additives may be included to obtain specific end-use properties and improve processing, storage, and handling characteristics. Despite their strength and low weight, composites have not been a miracle solution for aircraft structures. Composites are typically difficult to inspect for flaws. Some of them absorb moisture. Most importantly, they can be prohibitively expensive, primarily because they are labor-intensive and often require complex and expensive fabrication machines. Aluminium, by contrast, is easy and inexpensive to manufacture and repair, for example in a minor collision an aluminium component can often be hammered back into its original shape, whereas a crunched fiberglass component will likely have to be completely replaced. Aluminium has a relatively high fracture toughness, allowing it to undergo large amounts of plastic deformation before failure. Composites, on the other hand, are less damage tolerant and undergo much less plastic deformation before failure. An airplane made entirely from aluminium can be repaired almost anywhere. This is not the case for composite materials, particularly as they use different and more exotic materials. Because of this, composites will probably always be used more in military aircraft, which are constantly being maintained, than in commercial aircraft, which have to require less maintenance | https://en.wikipedia.org/wiki?curid=27616733 | 71,707 |
General Electric The reasons given were it "would create or strengthen dominant positions on several markets and that the remedies proposed by GE were insufficient to resolve the competition concerns resulting from the proposed acquisition of Honeywell". On June 27, 2014, GE partnered with collaborative design company Quirky to announce its connected LED bulb called Link. The Link bulb is designed to communicate with smartphones and tablets using a mobile app called Wink. In December 1985, GE reacquired RCA, primarily for the NBC television network (also parent of Telemundo Communications Group) for $6.28 billion; this merger surpassed the Capital Cities/ABC merger that happened earlier that year as the largest non-oil merger in world business history. The remainder was sold to various companies, including Bertelsmann (Bertelsmann acquired RCA Records) and Thomson SA, which traces its roots to Thomson-Houston, one of the original components of GE. Also in 1986, Kidder, Peabody & Co., a U.S.-based securities firm, was sold to GE and following heavy losses was sold to PaineWebber in 1994. In 2002, Francisco Partners and Norwest Venture Partners acquired a division of GE called GE Information Systems (GEIS). The new company, named GXS, is based in Gaithersburg, Maryland. GXS is a provider of B2B e-Commerce solutions. GE maintains a minority stake in GXS. Also in 2002, GE Wind Energy was formed when GE bought the wind turbine manufacturing assets of Enron Wind after the Enron scandals | https://en.wikipedia.org/wiki?curid=12730 | 395,713 |
Ion exchange Typical examples of ions that can bind to ion exchangers are: Along with absorption and adsorption, ion exchange is a form of sorption. is a reversible process, and the ion exchanger can be "regenerated" or "loaded" with desirable ions by washing with an excess of these ions. is widely used in the food and beverage industry, hydrometallurgy, metals finishing, chemical, petrochemical, pharmaceutical technology, sugar and sweetener production, ground- and potable-water treatment, nuclear, softening, industrial water treatment, semiconductor, power, and many other industries.. A typical example of application is preparation of high-purity water for power engineering, electronic and nuclear industries; i.e. polymeric or mineralic insoluble ion exchangers are widely used for water softening, water purification, water decontamination, etc. is a method widely used in household (laundry detergents and water filters) to produce soft water. This is accomplished by exchanging calcium Ca and magnesium Mg cations against Na or H cations (see water softening). Another application for ion exchange in domestic water treatment is the removal of nitrate and natural organic matter. Industrial and analytical ion-exchange chromatography is another area to be mentioned. Ion-exchange chromatography is a chromatographical method that is widely used for chemical analysis and separation of ions. For example, in biochemistry it is widely used to separate charged molecules such as proteins | https://en.wikipedia.org/wiki?curid=1615106 | 98,116 |
Torin Building One module provided an entrance for plant employees and support facilities: toilets, locker rooms and stairs. The other contained an entrance for visitors and office personnel, and mechanical space, toilets and stairs. Access to the high rise storage unit was provided at both manufacturing levels. The multitude of components required in the manufacturing process were moved in and out of the 20-metre high storage system by a single rail-guided vehicle as the various manufacturing operations were performed. Because processing lines were adjacent to container racking on both floors, load distances were very short. Once positioned in a pick-up station, loads could be moved by a storage vehicle for weight check and storage in less than a quarter of the time expected of a conventional fork-lift truck. Storage was accessible only to a special vehicle. This ensured parts, quantity and location integrity and eliminated the shutdown usually required for the taking of inventory. All walls of the complete steel framed structure, except the north/south walls are of concrete block, cavity wall construction, the outer skin consisting of split-face block. Office areas and the lower floor manufacturing areas included precast concrete window units similar to those first developed by the architects for the Torin Technical Centre in Torrington, Connecticut, US in 1971. These units in all cases faced north and were designed to provide adequate sun shade | https://en.wikipedia.org/wiki?curid=58749840 | 306,012 |
Parkinson's disease In 2013 PD resulted in about 103,000 deaths globally, up from 44,000 deaths in 1990. The death rate increased from an average of 1.5 to 1.8 per 100,000 during that time. PD is the second most common neurodegenerative disorder after Alzheimer's disease and affects approximately seven million people globally and one million people in the United States. The proportion in a population at a given time is about 0.3% in industrialized countries. PD is more common in the elderly and rates rise from 1% in those over 60 years of age to 4% of the population over 80. The mean age of onset is around 60 years, although 5–10% of cases, classified as young onset PD, begin between the ages of 20 and 50. Males are more often affected than females at a ratio of around 3:2. PD may be less prevalent in those of African and Asian ancestry, although this finding is disputed. Some studies have proposed that it is more common in men than women, but others failed to detect any differences between the two sexes. The number of new cases per year of PD is between 8 and 18 per 100,000 person–years. The age adjusted rate of in Estonia is 28.0/100,000 person years. The Estonian rate has been stable between 2000 and 2019. Several early sources, including an Egyptian papyrus, an Ayurvedic medical treatise, the Bible, and Galen's writings, describe symptoms resembling those of PD. After Galen there are no references unambiguously related to PD until the 17th century | https://en.wikipedia.org/wiki?curid=22228064 | 141,360 |
Tone control circuit Nonetheless, digital approaches are increasingly being implemented through the use of digital signal processing. NB. The above mentioned file should now be downloaded from Also, an article referenced by it entitled "Simple Tone Control Circuit: Bass and Treble, Cut and Lift, by E.J.James" may be downloaded from there as well. | https://en.wikipedia.org/wiki?curid=2233335 | 372,438 |
Mohamedou Ould Slahi "CBS News" journalist Holly Williams traveled to Mauritania to interview Slahi. "CBS News" flagship news show, "60 Minutes", broadcast the story on March 12, 2017. "CBS News" described it as Slahi's first television interview since his repatriation. In this interview Mohamedou said he "wholeheartedly [forgives] everyone who wronged [him] during [his] detention." In May 2018, Slahi's former guard at Guantanamo, Steve Wood, visited him in Mauritania over Ramadan in what long-time Guantanamo reporter Carol Rosenberg described as a 'remarkable reunion'. Slahi's passport has not been returned to him as was promised during his release. He is not able to leave Mauritania to treat his health condition or see his newborn son in Germany. | https://en.wikipedia.org/wiki?curid=881741 | 389,408 |
Boyne Obelisk The (), also known as King William's Obelisk, was an obelisk located in Oldbridge, near Drogheda, County Louth, Ireland. The monument was erected in order to commemorate William of Orange's victory over King James II at the Battle of the Boyne in 1690, and was located near the spot where William's forces crossed the River Boyne to engage James' forces. The foundation stone was laid on 17 April 1736 by Lionel Sackville, Lord Lieutenant of Ireland. The obelisk stood until 31 May 1923, when it was destroyed during the Irish Civil War by members of the National Army, allegedly using three landmines stolen from a nearby Irish Army camp. Only a small stump remains of the former monument. The Obelisk was made from granite and was built upon a large mound of rock (9 metres/30 ft high) located on the north bank of the River Boyne. At a height of 53 metres (174 ft), it was both the tallest man-made structure in Ireland and the tallest obelisk in Europe at the time of its construction. It initially stood adjacent to a wooden bridge spanning the river, which was later replaced by a lattice iron bridge that was built in 1869 and named the Obelisk Bridge, after the monument. The square base of the Obelisk bore an inscription on each of its sides. The north side inscription read: The south side inscription read: The east side inscription read: The west side inscription read: | https://en.wikipedia.org/wiki?curid=58118240 | 305,513 |
List of unmanned aerial vehicle applications Unmanned aerial vehicles are used across the world for civilian, commercial, as well as military applications. This is an incomplete list of those applications. Airlines and maintenance, repair, and operations contractors use UAVs for aircraft maintenance. In June 2015 EasyJet began testing UAVs in the maintenance of their Airbus A320s and in July 2016 at the Farnborough Airshow, Airbus (manufacturer of the A320), demonstrated the use of UAVs for the visual inspection of an aircraft. However, some aircraft maintenance professionals remain wary of the technology and its ability to properly catch potential dangers. A helicopter UAV has been proposed to accompany a future NASA Mars rover mission. Investigators believe a solar-powered craft would be able to fly for a few minutes at a time despite the thin atmosphere of the planet, and help the rover scout out interesting destinations. UAVs are used by a broad range of military forces, from Argentina to the US and also by Islamic State of Iraq and the Levant (ISIS). As of January 2014, the U.S. military operated 7,362 RQ-11B Ravens; 145 AeroVironment RQ-12A Wasps; 1,137 AeroVironment RQ-20A Pumas; 306 RQ-16 T-Hawk small UAS; 246 Predators and MQ-1C Grey Eagles; 126 MQ-9 Reapers; 491 RQ-7 Shadows and 33 RQ-4 Global Hawk large systems. The MQ-9 Reaper costs $12 million while a manned F-22 costs over $120 million. ISIS announced a "Unmanned Aircraft of the Mujahideen" unit in January 2017 and use drones for both reconnaissance and to drop bombs | https://en.wikipedia.org/wiki?curid=56002175 | 263,903 |
Electronics and semiconductor manufacturing industry in India The government has fostered an environment conducive to foreign direct investment (FDI) inflow in a number of ways, as outlined in the National Electronics Policy and the National Telecom Policy. The National Institution for Transforming India (NITI Aayog), a policy think-tank under the Indian central government, has suggested in a draft report that a policy be adopted to provide a tax holiday for a period of ten years to firms investing US$1 billion or more that also create 20,000 jobs. The report, hinting at a policy tilt toward the Information Technology Agreement-2 (ITA -2), also suggests that India should re-strategize its defensive policies regarding Free Trade agreements (FTAs) and aggressively pursue export-oriented policies to utilize these FTAs as opportunities to obtain duty-free access to the electronics markets of its FTA partners. The electronics sector in India attracted foreign direct investment or FDI (equity capital component only, and after excluding the amount remitted through Reserve Bank of India's NRI schemes) worth $1.636 billion between April 2000 and March 2016, which was 0.57% of the cumulative FDI equity inflow worth $288.51 billion the country received in the same period. , the government has received 156 proposals with investment commitments worth INR1.14 lakh crore or $16.8 billion in the previous 20 months, according to the India Electronics and Semiconductor Association (IESA), an organisation that promotes local manufacture of computer hardware and electronic goods in India | https://en.wikipedia.org/wiki?curid=51010296 | 397,194 |
Haploinsufficiency A variation of haploinsufficiency exists for mutations in the gene "PRPF31", a known cause of autosomal dominant retinitis pigmentosa. There are two wild-type alleles of this gene—a high-expressivity allele and a low-expressivity allele. When the mutant gene is inherited with a high-expressivity allele, there is no disease phenotype. However, if a mutant allele and a low-expressivity allele are inherited, the residual protein levels falls below that required for normal function, and disease phenotype is present. Copy-number variation (CNV) refers to the differences in the number of copies of a particular region of the genome. This leads to too many or too few of the dosage sensitive genes. The genomic rearrangements, that is, deletions or duplications, are caused by the mechanism of non-allelic homologous recombination (NAHR). In the case of the Williams Syndrome, the microdeletion includes the "ELN" gene. The hemizygosity of the elastinis is responsible for supravalvular aortic stenosis, the obstruction in the left ventricular outflow of blood in the heart. These include: | https://en.wikipedia.org/wiki?curid=1929037 | 169,242 |
Jet fuel The British Ministry of Defence establishes standards for both civil and military jet fuels. For reasons of inter-operational ability, British and United States military standards are harmonized to a degree. In Russia and former Soviet Union countries, grades of jet fuels are covered by the State Standard (GOST) number, or a Technical Condition number, with the principal grade available in Russia and members of the CIS being TS-1. Jet A specification fuel has been used in the United States since the 1950s and is usually not available outside the United States and a few Canadian airports such as Toronto and Vancouver, whereas Jet A-1 is the standard specification fuel used in the rest of the world other than the former Soviet states where TS-1 is the most common standard. Both Jet A and Jet A-1 have a flash point higher than , with an autoignition temperature of . The primary difference is the lower freezing point of A-1: The other difference is the mandatory addition of an anti-static additive to Jet A-1. Jet A trucks, storage tanks, and plumbing that carry Jet A are marked with a black sticker with "Jet A" in white printed on it, adjacent to another black stripe. Jet A-1 fuel must meet: Jet A fuel must reach ASTM specification D1655 (Jet A) Typical physical properties for Jet A / Jet A-1 Jet B is a naphtha-kerosene fuel that is used for its enhanced cold-weather performance. However, Jet B's lighter composition makes it more dangerous to handle. For this reason, it is rarely used, except in very cold climates | https://en.wikipedia.org/wiki?curid=1205435 | 49,526 |
Braina is an intelligent personal assistant application for Microsoft Windows developed by Brainasoft. uses natural language interface and speech recognition to interact with its users and allows users to use natural language sentences to perform various tasks on their computer. The application can find information from the internet, search and play songs and videos of user's choice, take dictation, find and open files, set alarms and reminders, performs math calculations, controls windows and programs etc. Braina's Android and iOS apps can be used to interact with the system remotely over a Wi-Fi network. The name is a short form of Brain Artificial. The software adapts to the user's behavior over time to better anticipate needs. The software also allows users to type commands using keyboard instead of saying them. comes in both free and paid version. Future plc's TechRadar recognized as one of the top 10 free essential software for 2015. comes in two versions: freeware Lite and Pro. | https://en.wikipedia.org/wiki?curid=45001424 | 475,390 |
Continua Health Alliance version 1 design guidelines are based on proven connectivity technical standards and include Bluetooth for wireless and USB for wired device connection. The group released the guidelines to the public in June 2009. The group is establishing a product certification program using its recognizable logo, the Continua Certified Logo program, signifying that the product is interoperable with other Continua-certified products. Products made under guidelines will provide consumers with increased assurance of interoperability between devices, enabling them to more easily share information with caregivers and service providers. Through collaborations with government agencies and other regulatory bodies, Continua works to provide guidelines for the effective management of diverse products and services from a global network of vendors. products make use of the ISO/IEEE 11073 Personal Health Data (PHD) Standards. Continua design guidelines are not available to the public without signing a Non-disclosure agreement. Continua's guidelines help technology developers build end-to-end, plug-and-play systems more efficiently and cost effectively. was founded on June 6, 2006 Continua Health alliance performed its first public demonstration of interoperability on October 27, 2008 at the Partners Center for Connected Health 5th Annual Connected Health Symposium in Boston. certified its first product, the Nonin 2500 PalmSAT handheld pulse oximeter with USB, on January 26, 2009 | https://en.wikipedia.org/wiki?curid=5627634 | 285,101 |
Oncogenomics BRAF encodes a serine/threonine kinase that is involved in the RAS-RAF-MAPK growth signaling pathway. Mutations in BRAF cause constitutive phosphorylation and activity in 59% of melanomas. Before BRAF, the genetic mechanism of melanoma development was unknown and therefore prognosis for patients was poor. Mitochondrial DNA (mtDNA) mutations are linked the formation of tumors. Four types of mtDNA mutations have been identified: Point mutations have been observed in the coding and non-coding region of the mtDNA contained in cancer cells. In individuals with bladder, head/neck and lung cancers, the point mutations within the coding region show signs of resembling each other. This suggests that when a healthy cell transforms into a tumor cell (a neoplastic transformation) the mitochondria seem to become homogenous. Abundant point mutations located within the non-coding region, D-loop, of the cancerous mitochondria suggest that mutations within this region might be an important characteristic in some cancers. This type of mutation is sporadically detected due to its small size ( < 1kb). The appearance of certain specific mtDNA mutations (264-bp deletion and 66-bp deletion in the complex 1 subunit gene ND1) in multiple types of cancer provide some evidence that small mtDNA deletions might appear at the beginning of tumorigenesis. It also suggests that the amount of mitochondria containing these deletions increases as the tumor progresses | https://en.wikipedia.org/wiki?curid=7737653 | 288,140 |
Screensaver For CRTs used in public, such as ATMs and railway ticketing machines, the risk of burn-in is especially high because a stand-by display is shown whenever the machine is not in use. Older machines designed without burn-in problems taken into consideration often display evidence of screen damage, with images or text such as "Please insert your card" (in the case of ATMs) visible even when the display changes while the machine is in use. Blanking the screen is out of the question as the machine would appear to be out of service. In these applications, burn-in can be prevented by shifting the position of the display contents every few seconds, or by having a number of different images that are changed regularly. Later CRTs were much less susceptible to burn-in than older models due to improvements in phosphor coatings, and because modern computer images are generally lower contrast than the stark green- or white-on-black text and graphics of earlier machines. LCD computer monitors, including the display panels used in laptop computers, are not susceptible to burn-in because the image is not directly produced by phosphors (although they can suffer from a less extreme and usually non-permanent form of image persistence). While modern screens are not susceptible to the issues discussed above, screensavers are still used. Primarily these are for decorative/entertainment purposes, or for password protection. They usually feature moving images or patterns and sometimes sound effects | https://en.wikipedia.org/wiki?curid=89769 | 381,243 |
Speedometer Pulse information is also used for a variety of other purposes by the ECU or full-vehicle control system, e.g. triggering ABS or traction control, calculating average trip speed, or to increment the odometer in place of it being turned directly by the speedometer cable. Another early form of electronic speedometer relies upon the interaction between a precision watch mechanism and a mechanical pulsator driven by the car's wheel or transmission. The watch mechanism endeavors to push the speedometer pointer toward zero, while the vehicle-driven pulsator tries to push it toward infinity. The position of the speedometer pointer reflects the relative magnitudes of the outputs of the two mechanisms. Typical bicycle speedometers measure the time between each wheel revolution, and give a readout on a small, handlebar-mounted digital display. The sensor is mounted on the bike at a fixed location, pulsing when the spoke-mounted magnet passes by. In this way, it is analogous to an electronic car speedometer using pulses from an ABS sensor, but with a much cruder time/distance resolution – typically one pulse/display update per revolution, or as seldom as once every 2–3 seconds at low speed with a 26-inch (2.07 m circumference, without tire) wheel. However, this is rarely a critical problem, and the system provides frequent updates at higher road speeds where the information is of more importance | https://en.wikipedia.org/wiki?curid=576681 | 347,275 |
Lectorium The (, ) is a non-profit organization headquartered in Rostov-on-Don, Russia. It produce enlightenment and edutainment open events and projecting a worldwide on-line educational center. Make all worldwide on-line educational products free and open for people. The enlightenment project was founded on September 26, 2009. Now (on May 11, 2011) it produced more than 80 events. Every week project is producing edutainment and enlightenment events with participation of local celebrities and young sciences. The produce different format open events: discussions, lectures, seminars, etc. in Rostov-on-Don was organized by cooperation of Wikimedia RU and Lectorium. Now team works on worldwide open on-line educational center. | https://en.wikipedia.org/wiki?curid=27892685 | 230,863 |
Transimpedance amplifier The feedback capacitor "C" is usually required to improve stability. The frequency response of a transimpedance amplifier is inversely proportional to the gain set by the feedback resistor. The sensors which transimpedance amplifiers are used with usually have more capacitance than an op-amp can handle. The sensor can be modeled as a current source and a capacitor "C". This capacitance across the input terminals of the op-amp, which includes the internal capacitance of the op-amp, introduces a low-pass filter in the feedback path. The low-pass response of this filter can be characterized as the feedback factor: formula_3 When the effect of this low-pass filter response is considered, the circuit's response equation becomes: formula_4 where formula_5 is the open-loop gain of the op-amp. At low frequencies the feedback factor β has little effect on the amplifier response. The amplifier response will be close to the ideal: formula_6 as long as the loop gain : formula_7 is much greater than unity. In the Bode plot of a transimpedance amplifier with no compensation, the flat curve with the peak, labeled I-to-V gain, is the frequency response of the transimpedance amplifier. The peaking of the gain curve is typical of uncompensated or poorly compensated transimpedance amplifiers. The curve labeled "A" is the open-loop response of the amplifier. The feedback factor, plotted as a reciprocal, is labeled 1/β. In Fig. 4 the 1/β curve and "A" form an isosceles triangle with the frequency axis | https://en.wikipedia.org/wiki?curid=30862800 | 413,093 |
Active rectification Active rectification, or synchronous rectification, is a technique for improving the efficiency of rectification by replacing diodes with actively controlled switches, usually power MOSFETs or power BJTs. Whereas normal semiconductor diodes have a roughly fixed voltage drop of around 0.5-1 volts, active rectifiers behave as resistances, and can have arbitrarily low voltage drop. Historically, vibrator driven switches or motor-driven commutators have also been used for mechanical rectifiers and synchronous rectification. has many applications. It is frequently used for arrays of photovoltaic panels to avoid reverse current flow that can cause overheating with partial shading while giving minimum power loss. It is also used in switched-mode power supplies (SMPS). The constant voltage drop of a standard p-n junction diode is typically between 0.7 V and 1.7 V, causing significant power loss in the diode. Electric power depends on current and voltage: the power loss rises proportional to both current and voltage. In low voltage converters (around 10 volts and less), the voltage drop of a diode (typically around 0.7 to 1 volt for a silicon diode at its rated current) has an adverse effect on efficiency. One classic solution replaces standard silicon diodes with Schottky diodes, which exhibit very low voltage drops (as low as 0.3 volts). However, even Schottky rectifiers can be significantly more lossy than the synchronous type, notably at high currents and low voltages | https://en.wikipedia.org/wiki?curid=18634614 | 369,936 |
Embodied cognitive science The most dramatic difference is that the principles are applicable only to situated robotic agents in the real world, a domain where traditional artificial intelligence showed the least promise. "Principle of cheap design and redundancy": Pfeifer realized that implicit assumptions made by engineers often substantially influence a control architecture's complexity. This insight is reflected in discussions of the scalability problem in robotics. The internal processing needed for some bad architectures can grow out of proportion to new tasks needed of an agent. The proposed solutions are to have the agent exploit the inherent physics of its environment, to exploit the constraints of its niche, and to have agent morphology based on parsimony and the principle of Redundancy. Redundancy reflects the desire for the error-correction of signals afforded by duplicating like channels. Additionally, it reflects the desire to exploit the associations between sensory modalities. (See redundant modalities). In terms of design, this implies that redundancy should be introduced with respect not only to one sensory modality but to several. It has been suggested that the fusion and transfer of knowledge between modalities can be the basis of reducing the size of the sense data taken from the real world. This again addresses the scalability problem. "Principle of parallel, loosely-coupled processes": An alternative to hierarchical methods of knowledge and action selection | https://en.wikipedia.org/wiki?curid=6338699 | 267,155 |
Species inquirenda In biological classification, a species inquirenda is a species of doubtful identity requiring further investigation. The use of the term in English-language biological literature dates back to at least the early nineteenth century. The term taxon inquirendum is broader in meaning and refers to an incompletely defined taxon of which the taxonomic validity is uncertain or disputed by different experts or is impossible to identify the taxon. Further characterization is required. | https://en.wikipedia.org/wiki?curid=26858533 | 177,275 |
Stöber process Decoupling the hydrolysis and condensation process affords a level of product control that is substantially superior to that afforded by the one-step Stöber process, with particle size controlled nearly completely by the sodium fluoride-to-TEOS ratio. The two-step begins with a mixture of TEOS, water, alcohol, and a nonionic surfactant, to which hydrochloric acid is added to produce a microemulsion. This solution is allowed to stand until hydrolysis is complete, much like in the one-step but with the hydrochloric acid replacing the ammonia as catalyst. Sodium fluoride is added to the resulting homogeneous solution, initiating the condensation reaction by acting as nucleation seed. The silica particles are collected by filtration and calcined to remove the nonionic surfactant template by combustion, resulting in the mesoporous silica product. The selection of conditions for the process allows for control of pore sizes, particle diameter, and their distributions, as in the case of the one-step approach. Porosity in the modified process is controllable through the introduction of a swelling agent, the choice of temperature, and the quantity of sodium fluoride catalyst added. A swelling agent (such as mesitylene) causes increases in volume and hence in pore size, often by solvent absorption, but is limited by the solubility of the agent in the system. Pore size varies directly with temperature, bound by the lower out of the surfactant cloud point and the boiling point of water | https://en.wikipedia.org/wiki?curid=32297166 | 76,459 |
NGC 840 is a barred spiral galaxy in the constellation Cetus south of the ecliptic . It is estimated to be 327 million light years from the Milky Way and has a diameter of approximately 175,000 lys. | https://en.wikipedia.org/wiki?curid=63410607 | 6,197 |
Musick Guard Station The cabin has two wooden platform beds and four bunk bed sets; however, there are no mattresses. The cabin is also furnished with table and chairs. In the living room, there is a wood-burning stove for heat. In the kitchen, there is a wood-burning cook stove. The cabin does not have electricity or water. There is a vault-type outhouse located near the cabin. A horse barn, a small shed, an outdoor fireplace with a cooking grill, and a picnic table are also located on the guard station grounds. There is room for tent camping at the site as well. In the summer, visitors can hike nearby trails. The Bohemia Mountain Trail is a particularly popular. The trailhead is a little over a mile from the guard station. From there, it is a 3/4 mile hike to the summit of Bohemia Mountain which is highest point on the Cottage Grove Ranger District. However, it is not an easy hike with grades averaging 15-20 percent most of the way. A one-way trip takes about an hour from the trailhead. Hikers must pack their own water since none is available on the trail. From the summit of Bohemia Mountain there is an excellent view of the Cascade Range from Mount Hood to Mount Shasta. Another popular hike is to the summit of near-by Fairview Peak. Fairview Peak summit is about two miles (3 km) from the guard station. At the top there is a fire lookout tower that is manned during the summer. When a Forest Service lookout is in residence, the tower is open to the public | https://en.wikipedia.org/wiki?curid=18051740 | 314,073 |
Mineralized tissues In bone, studies have shown that calcium phosphate nucleates within the hole area of the collagen fibrils and then grows in these zones until it occupies the maximum space. The organic part of mineralized tissues is made of proteins. In bone for example, the organic layer is the protein collagen. The degree of mineral in mineralized tissues varies and the organic component occupies a smaller volume as tissue hardness increases. However, without this organic portion, the biological material would be brittle and break easily. Hence, the organic component of mineralized tissues increases their toughness. Moreover, many proteins are regulators in the mineralization process. They act in the nucleation or inhibition of hydroxyapatite formation. For example, the organic component in nacre is known to restrict the growth of aragonite. Some of the regulatory proteins in mineralized tissues are osteonectin, osteopontin, osteocalcin, bone sialoprotein and dentin phosphophoryn. In nacre, the organic component is porous, which allows the formation of mineral bridges responsible for the growth and order of the nacreous tablets. Understanding the formation of biological tissues is inevitable in order to properly reconstruct them artificially. Even if questions remain in some aspects and the mechanism of mineralization of many mineralized tissues need yet to be determined, there are some ideas about those of mollusc shell, bone and sea urchin | https://en.wikipedia.org/wiki?curid=25249955 | 177,168 |
NGC 3274 is a relatively faint spiral galaxy discovered by Wilhelm Herschel in 1783, and is located over 20 million light-years away in the constellation of Leo. | https://en.wikipedia.org/wiki?curid=52351735 | 8,327 |
Unbalanced line In electrical engineering, an unbalanced line is a transmission line, often coaxial cable, whose conductors have unequal impedances with respect to ground; as opposed to a balanced line. Microstrip and single-wire lines are also unbalanced lines. Any line that has a different impedance of the return path may be considered an unbalanced line. However, unbalanced lines usually consist of a conductor that is considered the signal line and another conductor that is grounded, or is ground itself. The ground conductor often takes the form of a ground plane or the screen of a cable. The ground conductor may be, and often is, common to multiple independent circuits. For this reason the ground conductor may be referred to as "common". The earliest use of unbalanced transmission lines was for electric telegraph communications. These consisted of single wires strung between poles. The return path for the current was originally provided by a separate conductor. Some early telegraph systems, such as Schilling's experimental needle telegraph (1832) and the Cooke & Wheatstone five-needle telegraph (1837) used by British railways required multiple code wires. Essentially, they were parallel bus coding. In these systems the cost of the return conductor was not so significant (one conductor in seven for Schilling's earliest needle telegraph and one conductor in six for the Cooke and Wheatstone telegraph) but the number of coding conductors was progressively reduced with improved systems | https://en.wikipedia.org/wiki?curid=2803396 | 416,184 |
4K resolution Dome Productions, a joint venture of Bell Media and Rogers Media (the respective owners of TSN and Sportsnet), constructed a "side-by-side" 4K mobile production unit shared by Sportsnet and TSN's first 4K telecasts; it was designed to operate alongside a separate HD truck and utilize cameras capable of output in both formats. For the opening game of the 2016 Toronto Blue Jays season, Dome constructed "Trillium" a production truck integrating both 4K and 1080i high-definition units. Bell Media's CTV also broadcast the 2016 Juno Awards in 4K as the first awards show presented in the format. In February 2016, Univision trialed 4K by producing a closed circuit telecast of a football friendly between the national teams of Mexico and Senegal from Miami in the format. The broadcast was streamed privately to several special viewing locations. Univision aimed to develop a 4K streaming app to publicly televise the final of Copa América Centenario in 4K. In March 2016, DirecTV and CBS Sports announced that they would produce the "Amen Corner" supplemental coverage from the Masters golf tournament in 4K. After having trialed the technology in limited matches at the 2013 FIFA Confederations Cup, and the 2014 FIFA World Cup (via private tests and public viewings in the host city of Rio de Janeiro), the 2018 FIFA World Cup was the first FIFA World Cup in which all matches were produced in 4K | https://en.wikipedia.org/wiki?curid=27168879 | 228,673 |
Biotransformation Functional genomic and metagenomic approaches are increasing our understanding of the relative importance of different pathways and regulatory networks to carbon flux in particular environments and for particular compounds and they are accelerating the development of bioremediation technologies and biotransformation processes. Also there is other approach of biotransformation called enzymatic biotransformation. Petroleum oil is toxic for most life forms and episodic and chronic pollution of the environment by oil causes major ecological perturbations. Marine environments are especially vulnerable, since oil spills of coastal regions and the open sea are poorly containable and mitigation is difficult. In addition to pollution through human activities, millions of tons of petroleum enter the marine environment every year from natural seepages. Despite its toxicity, a considerable fraction of petroleum oil entering marine systems is eliminated by the hydrocarbon-degrading activities of microbial communities, in particular by a remarkable recently discovered group of specialists, the so-called hydrocarbonoclastic bacteria (HCB). "Alcanivorax borkumensis", a paradigm of HCB and probably the most important global oil degrader, was the first to be subjected to a functional genomic analysis | https://en.wikipedia.org/wiki?curid=11594369 | 263,561 |
Air conditioning Such systems might be the right solution for maintaining the microclimate in several offices, shops, large living spaces. Just few of outdoor units do not worsen the aesthetic appearance of the building. The main external unit can be connected to several different indoor types: floor, ceiling, cassette, etc. Before selecting the installation location of air conditioner, several main factors need to be considered. First of all, the direction of air flow from the indoor units should not fall on the place of rest or work area. Secondly, there should not be any obstacles on the way of the airflow that might prevent it from covering the space of the premises as much as possible. The outdoor unit must also be located in an open space, otherwise the heat from the house will not be effectively discharged outside and the productivity of the entire system will drop sharply. It is highly advisable to install the air conditioner units in easily accessible places, for further maintenance during operation. The main problem when installing a multi-split system is the laying of long refrigerant lines for connecting the external unit to the internal ones. While installing a separate split system, workers try to locate both units opposite to each other, where the length of the line is minimal. Installing a multi-split system creates more difficulties, since some of indoor units can be located far from the outside | https://en.wikipedia.org/wiki?curid=7221088 | 299,633 |
Shanon Shah (born 14 August 1978 in Alor Star, Kedah), is a singer-songwriter, playwright and journalist from Malaysia. He released two albums "Dilanda Cinta" (2005) and "Suara Yang Ku Dengar" (2010) on the InterGlobal Music Malaysia independent label. He is noted for his emotive voice and cabaret-style piano playing. Trained as a chemical engineer, Shanon has previously worked as a credit risk analyst, human rights advocate and journalist. In his various writings, he focuses on issues relating to gender, sexuality and Islam. In 2003, Shanon won the Mandarin Oriental Fan of the Arts Most Promising Artist Award at the 2nd Annual Boh Cameronian Arts Awards. Two years later, he went on to win the Anugerah Industri Muzik award for best male vocal in an album for "Dilanda Cinta". In 2007, he entered the Ikon Malaysia televised competition which looked for an icon among existing Southeast Asian artistes. The Malaysian level of the competition was ultimately won by Jaclyn Victor. Shanon has also performed as a duo with fellow singer-songwriter Azmyl Yunor and with his backing band the Cintas. Fellow singer-songwriter Ariff Akhir has also performed as part of the Cintas, and produced Shanon's second album, "Suara Yang Ku Dengar". Shanon's musical influences include Leonard Cohen, Aimee Mann and Sam Phillips. is also a playwright. His play "Air Con" was by the Instant Cafe Theatre Company's FIRSTWoRKS programme. The play, directed by Jo Kukathas and Zalfian Fuzi, was performed to critical acclaim prompting a revival in 2009 | https://en.wikipedia.org/wiki?curid=7406806 | 42,425 |
Mobile office A mobile office is an office built within a truck, motorhome, trailer or purpose built shipping container. Most common are towable offices built on an axled iron frame for easy relocation. Mobile field offices are often found on construction sites, or at disaster scenes where a temporary office space is needed. Typically, mobile offices in North America feature a single phase split (240 volt center-tapped) electric service that is connected to a nearby source of power, to run small window-unit air conditioners, and the like. There are many types of companies that sell, lease, rent new and used storage containers, portable buildings or modular buildings. This type of construction shortens the construction period as the building can be built in a factory in as little as six weeks and the site and utility work can be done in conjunction with the construction of the building. The term "mobile office" is also used for the workspace of salespeople or similar, working out of their company office. They are usually equipped with a portable computer and connect to the company servers and Intranet via mobile phones, WiFi or via fixed connections in cybercafes, hotels and airports. They like to use Personal Information Managers Because they must carry their equipment, mobile office workers push for miniaturization of devices. | https://en.wikipedia.org/wiki?curid=994039 | 217,400 |
J. Karl Hedrick (August 26, 1944 – February 22, 2017) was an American control theorist and a Professor in the Department of Mechanical Engineering at the University of California, Berkeley. He made seminal contributions in nonlinear control and estimation. Prior to joining the faculty at the University of California, Berkeley he was a professor at the Massachusetts Institute of Technology from 1974 to 1988. Hedrick received a bachelor's degree in Engineering Mechanics from the University of Michigan (1966) and a M.S. and Ph.D from Stanford University (1970, 1971). Hedrick was the head of the Vehicle Dynamics and Control Laboratory at UC Berkeley. He led Partners for Advanced Transit and Highways Research Center (1997–2003), which conducts research in advanced vehicle control systems, advanced traffic management and information systems, and technology leading to an automated highway systems. He wrote two books and published more than 140 peer-reviewed archival publications, and graduated over 70 Ph.D. students in his career at MIT, Arizona State, and Berkeley. He was awarded the Rufus Oldenburger Medal from the American Society of Mechanical Engineers in 2006 and was elected to the National Academy of Engineering in 2014. | https://en.wikipedia.org/wiki?curid=25366391 | 139,439 |
Vibration isolation is the process of isolating an object, such as a piece of equipment, from the source of vibrations. Vibration is undesirable in many domains, primarily engineered systems and habitable spaces, and methods have been developed to prevent the transfer of vibration to such systems. Vibrations propagate via mechanical waves and certain mechanical linkages conduct vibrations more efficiently than others. Passive vibration isolation makes use of materials and mechanical linkages that absorb and damp these mechanical waves. Active vibration isolation involves sensors and actuators that produce disruptive interference that cancels-out incoming vibration. "Passive vibration isolation" refers to vibration isolation or mitigation of vibrations by passive techniques such as rubber pads or mechanical springs, as opposed to "active vibration isolation" or "electronic force cancellation" employing electric power, sensors, actuators, and control systems. Passive vibration isolation is a vast subject, since there are many types of passive vibration isolators used for many different applications. A few of these applications are for industrial equipment such as pumps, motors, HVAC systems, or washing machines; isolation of civil engineering structures from earthquakes (base isolation), sensitive laboratory equipment, valuable statuary, and high-end audio | https://en.wikipedia.org/wiki?curid=4449103 | 202,559 |
Tandem affinity purification There may also be a possibility of a cleavage of the proteins by the TEV protease, although this is unlikely to be frequent given the high specificity of the TEV protease. As this method involves at least 2 rounds of washing, it may not be suitable for screening transient protein interactions, unlike the yeast two-hybrid method or "in vivo" crosslinking with photo-reactive amino acid analogs. However, it is a good method for testing stable protein interactions and allows various degrees of investigation by controlling the number of times the protein complex is purified. In 2002, the TAP tag was first used with mass spectrometry in a large-scale approach to systematically analyse the proteomics of yeast by characterizing multiprotein complexes. The study revealed 491 complexes, 257 of them wholly new. The rest were familiar from other research, but now virtually all of them were found to have new components. They drew up a map relating all the protein components functionally in a complex network. Many other proteomic analyses also involve the use of TAP tag. A research by EMBO (Dziembowski, 2004) identified a new complex required for nuclear pre-mRNA retention and splicing. They have purified a novel trimeric complex composed of 3 other subunits (Snu17p, Bud13p and Pml1p) and find that these subunits are not essential for viability but required for efficient splicing (removal of introns) of pre-mRNA. In 2006, "Fleischer et al." systematically identified proteins associated with eukaryotic ribosomal complexes | https://en.wikipedia.org/wiki?curid=9931632 | 55,126 |
Indoor air pollution in developing nations Careful selection of regenerating varieties would be most sustainable because soil stability is not disrupted due to tilling and planting. Some people view this solution as a way to further exploit forests, but with proper management of forest resources this could be a viable solution. Fuels and cook stove technology can be assessed on two factors: energy efficiency and emissions in the household. High-performing efficient stoves can improve environmental outcomes to an extent even with unclean fuels (such as firewood and biomass). According to a study comparing environmental, social, and economic life cycle impacts of cooking fuels, with more efficient stoves “more of the heating value of the fuel is converted into useful cooking energy and therefore less fuel must be produced, transported, and burned to deliver the same amount of cooking.” Other sustainable options include liquid and gas fuels that are combusted in high-performing efficient stoves. For instance, ethanol produced from cellulosic/non-food feedstocks (wood, agricultural residue) has lower environmental life cycle impacts compared to ethanol produced from sugar and starch materials. LPG, though made from non-renewable fossil fuels, still has lower negative environmental impacts than traditional fuels – thus even though it is not a sustainable alternative, it creates far less emissions impacts than traditional fuels. There exist trade-offs between efficiency and sustainability on the supply side of the cook stoves and fuels market | https://en.wikipedia.org/wiki?curid=11655845 | 364,910 |
Gin pole A gin pole is a supported pole that uses a pulley or block and tackle on its upper end to lift loads. The lower end is braced or set in a shallow hole and positioned so the upper end lies above the object to be lifted. The pole (also known as a "mast", "boom", or "spar") is secured with three or more guy-wires. These are manipulated to move the load laterally, with up and down controlled by the pulley or block. A gin pole can also be “jumped” to build a tower. The gin pole is derived from a gyn, and considered a form of derrick, called a standing derrick or pole derrick, distinguished from sheers (or "shear legs") by having a single boom rather than a two-legged one. Gin poles are also used to raise loads above structures too tall to reach with a crane, such as placing an antenna on top of a tower/steeple, and to lift segments of a tower on top of one-another during erection. When used to create a segmented tower, the gin pole can be detached, raised, and re-attached to the just-completed segment in order to lift the next. This process of "jumping" is repeated until the topmost portion of the tower is completed. They can also hold a person if strong enough. Thus opening stage uses, such as in magic shows Gin poles are mounted on trucks as a primitive form of mobile crane, used for lifting and relocating loads, and salvage operations in lieu of a more sophisticated wrecker. | https://en.wikipedia.org/wiki?curid=4266962 | 276,588 |
Anemoscope An anemoscope is a device invented to show the direction of the wind, or to foretell a change of wind direction or weather. Hygroscopic devices, in particular those utilizing catgut, were considered as very good anemoscopes, seldom failing to foretell the shifting of the wind. The ancient anemoscope seems, by Vitruvius's description of it, to have been intended to show which way the wind actually blew, rather than to foretell into which quarter it would change. Otto von Guericke gave the title "anemoscope" to a machine invented by him to foretell the change of the weather, as to fair and rain. It consisted of a small wooden man who rose and fell in a glass tube as the atmospheric pressure increased or decreased. Accordingly, M. Comiers has shown that this was simply an application of the common barometer. This form of the anemoscope was invented by Leonardo da Vinci. | https://en.wikipedia.org/wiki?curid=3710466 | 4,299 |
Emergency Management BC Volunteer responders donate over 120,000 hours of their time on callouts and recent statistics show an astounding 95% of the subjects were found. Search and rescue is further broken down into individual teams what operate in an area of the province where they are responsible for familiarity and access (e.g., North Shore Rescue). They may be tasked from a variety of agencies such as the Royal Canadian Mounted Police, local police force, BC Ambulance, or the Coroner's service, and can be called to assist the Coast Guard, Department of National Defence, and Parks Canada. A number of search and rescue teams in BC are also trained and equipped for using the Helicopter Flight Rescue System to aid in rescuing people from dangerous or remote terrain. In 2005 there were 93 individual SAR teams in the province, comprising approximately 4700 volunteers, and conducting an average of 900 operations per year, locating an average of 1200 people per year. EMBC-affiliated ground SAR teams in BC are represented by the British Columbia Search and Rescue Association, as well as by their individual teams. In 2017, EMBC signed a memorandum of understanding with the Royal Canadian Marine Search and Rescue (RCMSAR), which allows for provincial and local response agencies to access humanitarian assistance from RCMSAR in coastal and inland waterways. As a core function, RCMSAR responds to over 800 SAR missions annually from its 33 volunteer lifeboat stations. RCMSAR comprises over 1,100 volunteers and a small cadre of paid staff | https://en.wikipedia.org/wiki?curid=6123625 | 252,346 |
TechAmerica The Association of Data Processing Services Organization (ADAPSO) was formed in 1961. This association was renamed in 1991 to the Information Technology Association of America (ITAA). In 2008, ITAA merged with the Cyber Security Industry Alliance (CSIA) and the Government Electronics Industry Association (GEIA). The organization's website was attacked in April 2012 for their support of the controversial CISPA bill. In July 2013, sold its standards program to SAE International. On November 4, 2013 it was announced that four lobbyists: Trey Hodgkins, Pam Walker, Erica McCann and Carol Henton had resigned, lured to the Information Technology Industry Council (ITI) which was able to raise $50,000 each from more than a dozen of its members to fund the acquisition of the four lobbyists. filed a lawsuit against ITI and three of the departing lobbyists in D.C. Superior Court. TechAmerica's complaints include that the defecting lobbyists conspired in their new positions to use old contacts and other information acquired while at to help ITI find new clients for its neophyte effort focused on government procurement Todd Thibodeaux President & CEO Elizabeth Hyman Executive Vice President, Public Advocacy Nancy Hammervik Senior Vice President, Industry Relations David Sommer Chief Financial Officer L. Daniel Liutikas Chief Legal Officer | https://en.wikipedia.org/wiki?curid=22979159 | 273,416 |
Audio signal flow A typical application for the line trim is attenuating signals that were intentionally amplified too much by the microphone preamplifier. Over amplifying the signal can cause the preamplifier to distort, which can under certain circumstances produce a desirable sound. After the line trim, the signal is processed by the mixing board's EQ, filter, compressor, limiter, de-esser, delay, reverb, and any other signal processing features the mixing board has available and that the mix engineer chooses to use. The processed signal is then sent to the mix bus, where it is combined with all the other signals coming from the stage. The balance of signals is controlled by faders. The mix is then routed to one of the mixing boards outputs, and flows into a loudspeaker controller. This device processes the signal to optimize it for the sound system installed in the performance venue. It then flows into a rack of amplifiers, and then to the speakers. | https://en.wikipedia.org/wiki?curid=20312900 | 398,121 |
Botanical Latin More extensive modifications to the spelling and pronunciation are routinely used in some other languages. French organism names are usually gallicized. For example: "Chlorophyceae" becomes Chlorophycées; "Portulacineae" becomes Portulacinées. The Classical Latin alphabet consisted of 21 letters, to which w, y, and z were later added, and the vowel/consonant pairs i and j, u and v, were later separated. This 26-letter alphabet is used for taxon names in Botanical Latin. Diacritics are not used in names, and a dieresis is considered an optional mark that does not affect spelling. Some English speakers, and some speakers of other languages, use the reconstructed pronunciation guide for Classical Latin when speaking Botanical Latin. Latin names pronounced by gardeners and English botanists usually follow a system close to English. It differs greatly from Classical pronunciation, and also from Ecclesiastical Latin pronunciation (which is based on Italian, and has, for example, "c" before "i" or "e" pronounced as "ch"). Every vowel is pronounced, except diphthongs, which are treated as single long vowels. In classical Latin words of several syllables the stress falls on the syllable next to the last one (the penultimate) when this syllable is long ... e.g., "for-mō'-sus", or when two consonants separate the two last vowels, e.g., "cru-ěn'-tus" ... on the last syllable but two (the antepenultimate) when the last but one is short, e.g. "flō-ri-dus" | https://en.wikipedia.org/wiki?curid=51212902 | 186,295 |
Continuum mechanics The RVE may be assessed only in a limited way via experimental testing: when the constitutive response becomes spatially homogeneous. Specifically for fluids, the Knudsen number is used to assess to what extent the approximation of continuity can be made. Consider car traffic on a highway, with just one lane for simplicity. Somewhat surprisingly, and in a tribute to its effectiveness, continuum mechanics effectively models the movement of cars via a partial differential equation (PDE) for the density of cars. The familiarity of this situation empowers us to understand a little of the continuum-discrete dichotomy underlying continuum modelling in general. To start modelling define that: formula_1 measures distance (in km) along the highway; formula_2 is time (in minutes); formula_3 is the density of cars on the highway (in cars/km in the lane); and formula_4 is the flow velocity (average velocity) of those cars 'at' position formula_1. Cars do not appear and disappear. Consider any group of cars: from the particular car at the back of the group located at formula_6 to the particular car at the front located at formula_7. The total number of cars in this group formula_8. Since cars are conserved (if there is overtaking, then the `car at the front \ back' may become a different car) formula_9. But via the Leibniz integral rule This integral being zero holds for all groups, that is, for all intervals formula_11. The only way an integral can be zero for all intervals is if the integrand is zero for all formula_1 | https://en.wikipedia.org/wiki?curid=5918 | 48,903 |
MARTI Electronics Marti Electronics, a division of BE, manufactures RF Remote Pick-Up equipment for the broadcast industry. Marti has been supplying such hardware since 1960 with few competitors in its very vertical market. Because this equipment was so ubiquitous for so many years, the words "Marti" and "RPU" have become almost synonymous among broadcast engineers. Marti is headquartered in Quincy, Illinois. | https://en.wikipedia.org/wiki?curid=13251269 | 264,983 |
Cheque clearing When the manager signaled again, this procedure was repeated, so that after about six minutes, the clerks had completed all their assigned transactions and were back to their starting locations, and holding exactly the amount of cash their papers said they should be holding. Clerks were fined if they made errors and the amount of the fine increased rapidly as time passed. The Federal Reserve System check clearing system was established in the United States in 1913 to act as a central, well-capitalized clearing house. The objective was to prevent the occasional panics, where banks would refuse to accept cheques drawn on banks whose solvency was uncertain. The Federal Reserve can physically accept and transport cheques. When a bank customer deposits a cheque, which may be drawn on any bank, the bank would credit the depositor's account with the amount of the cheque. However, the amount so credited is “not available” to the depositor until the cheque has been cleared by the paying bank. For cheques drawn on a customer of the same bank, the bank would, usually on the next business day, ensure that the cheque is in order and debit the account of the drawer, and the cheque would be taken to have been cleared. A cheque is not in order if, for example, the date is invalid, the drawer's signature is not like the one held by the bank, the wrong number of signatories have signed the cheque, etc. There must also be sufficient cleared funds in the account before the drawer's account is debited | https://en.wikipedia.org/wiki?curid=485158 | 483,580 |
Molecular nanotechnology Molecular surgical tools, guided by molecular computers and injected into the blood stream could find and destroy cancer cells or invading bacteria, unclog arteries, or provide oxygen when the circulation is impaired. Nanotechnology will replace our entire manufacturing base with a new, radically more precise, radically less expensive, and radically more flexible way of making products. The aim is not simply to replace today's computer chip making plants, but also to replace the assembly lines for cars, televisions, telephones, books, surgical tools, missiles, bookcases, airplanes, tractors, and all the rest. The objective is a pervasive change in manufacturing, a change that will leave virtually no product untouched. Economic progress and military readiness in the 21st Century will depend fundamentally on maintaining a competitive position in nanotechnology. Despite the current early developmental status of nanotechnology and molecular nanotechnology, much concern surrounds MNT's anticipated impact on economics and on law. Whatever the exact effects, MNT, if achieved, would tend to reduce the scarcity of manufactured goods and make many more goods (such as food and health aids) manufacturable. MNT should make possible nanomedical capabilities able to cure any medical condition not already cured by advances in other areas. Good health would be common, and poor health of any form would be as rare as smallpox and scurvy are today. Even cryonics would be feasible, as cryopreserved tissue could be fully repaired | https://en.wikipedia.org/wiki?curid=19637 | 161,054 |
Total indicator reading In metrology and the fields that it serves (such as manufacturing, machining, and engineering), total indicator reading (TIR), also known by the newer name full indicator movement (FIM), is the difference between the maximum and minimum measurements, that is, readings of an indicator, on the planar, cylindrical, or contoured surface of a part, showing its amount of deviation from flatness, roundness (circularity), cylindricity, concentricity with other cylindrical features, or similar conditions. The indicator traditionally would be a dial indicator; today dial-type and digital indicators coexist. The earliest expansion of "TIR" was total indicated run-out and concerned cylindrical or tapered (conical) parts, where "run-out" (noun) refers to any imperfection of form that causes a rotating part such as a shaft to "run out" (verb), that is, to not rotate with perfect smoothness. These conditions include being out-of-round (that is, lacking sufficient roundness); eccentricity (that is, lacking sufficient concentricity); or being bent axially (regardless of whether the surfaces are perfectly round and concentric at every cross-sectional point). The purpose of emphasizing the "total" in TIR was to duly maintain the distinction between per-side differences and both-sides-considered differences, which requires perennial conscious attention in lathe work. For example, all depths of cut in lathe work must account for whether they apply to the radius (that is, per side) or to the diameter (that is, total) | https://en.wikipedia.org/wiki?curid=31353312 | 206,405 |
Econet With both floppy disc and networking available, the BBC Micro was approved for use in schools by all state and territory education authorities in Australia and New Zealand, and quickly overtook the Apple II as the computer of choice in private schools. With no other supporting documentation available, the head of Barson's Acorn division, Rob Napier, published "Networking with the BBC Microcomputer", the first reference documentation for Econet. was officially released for the BBC Micro in the UK in 1984, and it later became popular as a networking system for the Acorn Archimedes. was eventually supported on all post-Atom Acorn machines, apart from the Electron (except in Australia and New Zealand where Barson Computers built their own daughter board), the A3010, and the eventually-cancelled Phoebe 2100. was supported by Acorn MOS, RISC OS and RISC iX. Acorn once received an offer from Commodore International to license the technology, which it refused. An "Ecolink" ISA interface card for IBM-compatible PCs was available. It used Microsoft's MS-NET Redirector for MS-DOS to provide file and printer sharing via the NET USE command. With the falling prices and widespread adoption of IP networking in the early 1990s, Acorn Universal Networking (AUN), an implementation of protocols and addressing over TCP/IP, was developed to provide legacy support for on Ethernet-connected machines. The protocol and AUN were also supported by the Linux kernel | https://en.wikipedia.org/wiki?curid=1227761 | 100,988 |
Shot noise A semiconductor diode is thus commonly used as a noise source by passing a particular DC current through it. In other situations interactions can lead to an enhancement of shot noise, which is the result of a super-poissonian statistics. For example, in a resonant tunneling diode the interplay of electrostatic interaction and of the density of states in the quantum well leads to a strong enhancement of shot noise when the device is biased in the negative differential resistance region of the current-voltage characteristics. is distinct from voltage and current fluctuations expected in thermal equilibrium; this occurs without any applied DC voltage or current flowing. These fluctuations are known as Johnson–Nyquist noise or thermal noise and increase in proportion to the Kelvin temperature of any resistive component. However both are instances of white noise and thus cannot be distinguished simply by observing them even though their origins are quite dissimilar. Since shot noise is a Poisson process due to the finite charge of an electron, one can compute the root mean square current fluctuations as being of a magnitude where "q" is the elementary charge of an electron, Δ"f" is the single-sided bandwidth in hertz over which the noise is considered, and "I" is the DC current flowing. For a current of 100 mA, measuring the current noise over a bandwidth of 1 Hz, we obtain If this noise current is fed through a resistor a noise voltage of would be generated | https://en.wikipedia.org/wiki?curid=41700 | 379,733 |
Cell cycle analysis The objects measured within the sub-G/G peak, with DNA content lesser than 5% of that of the GG peak, in all probability are apoptotic bodies and thus do not represent individual apoptotic cells | https://en.wikipedia.org/wiki?curid=27382300 | 177,518 |
List of Dutch inventions and innovations It is further claimed that British soldiers who provided support in Antwerp against the Spanish in 1585, during the Eighty Years' War, were already drinking genever (jenever) for its calming effects before battle, from which the term "Dutch Courage" is believed to have originated. The earliest known written reference to genever appears in the 13th century encyclopaedic work "Der Naturen Bloeme" (Bruges), and the earliest printed genever recipe from 16th century work "Een Constelijck Distileerboec" (Antwerp). A stroopwafel (also known as "syrup waffle", "treacle waffle" or "caramel waffle") is a waffle made from two thin layers of baked batter with a caramel-like syrup filling the middle. They were first made in Gouda in the 1780s. The traditional way to eat the stroopwafel is to place it atop of a drinking vessel with a hot beverage (coffee, tea or chocolate) inside that fits the diameter of the waffle. The heat from the rising steam warms the waffle and slightly softens the inside and makes the waffle soft on one side while still crispy on the other. In 1815, Dutch chemist Coenraad van Houten introduced alkaline salts to chocolate, which reduced its bitterness. In the 1820s, Casparus van Houten, Sr. patented an inexpensive method for pressing the fat from roasted cocoa beans. He created a press to remove about half the natural fat (cacao butter) from chocolate liquor, which made chocolate both cheaper to produce and more consistent in quality. This innovation introduced the modern era of chocolate | https://en.wikipedia.org/wiki?curid=59732521 | 255,864 |
PICMG 2.5 is a specification by PICMG that standardizes the utilization of CompactPCI user definable pins for the computer telephony functions of standard TDM bus, telephony rear IO, 48 VDC and ringing distribution in a 6U chassis environment. | https://en.wikipedia.org/wiki?curid=24663914 | 284,177 |
Misattribution of memory The researchers were trying to determine the levels of activation for source recollection for the objects paired with the scene during encoding. The researchers found that perirhinal cortex activation was greater for objects recalled, and parahippocampal cortex activation was greater when scenes were recalled. The results provide evidence of distinct encoding activation in the subregions of the medial temporal lobe. The first subregion is the perirhinal cortex, which encodes item information. The second subregion, the parahippocampal cortex, is involved in source information. The evidence provides support for the role of the right perirhinal cortex in attributing an object to the right source. As decreased activation was associated with poorer performance, decreased activation of the right perirhinal cortex could be a possible mechanism for source confusion. In one of the earliest studies involving misattribution, the Canadian cognitive psychologist Bruce Whittlesea presented subjects with a list of common words. Each word was briefly displayed to the subject. The task required the subject to judge whether a target word was semantically related to any word in the list. Unlike Whittlesea's first experiment involving the recognition of target words, this study involved the manipulation of processing fluency through the conceptual context of the target word, rather than the physical context | https://en.wikipedia.org/wiki?curid=31133385 | 166,330 |
American system of manufacturing The armories also openly shared manufacturing techniques with private industry. Additionally, the idea migrated from the armories to industry as machinists trained in the armory system were hired by other manufacturers. Skilled engineers and machinists thus influenced American clockmakers and sewing machine manufacturers Wilcox and Gibbs and Wheeler and Wilson, who used interchangeable parts before 1860. Late to adopt the interchangeable system were Singer Corporation sewing machine (1870s), reaper manufacturer McCormick Harvesting Machine Company (1870s–80s) and several large steam engine manufacturers such as Corliss (mid-1880s) as well as locomotive makers. Large scale of production of bicycles in the 1880s used the interchangeable system. The idea would also help lead to the American "Golden Age" of manufacturing when Henry Ford mass-produced the automobile. Mastering true interchangeability on the assembly line, the Ford plant produced standard model cars. These efficient production strategies allowed these automobiles to be affordable for the middle class. The idea of interchangeable parts and the separate assembly line was not new, though it was little used. The idea was first developed in East Asia during the Warring States period and later the Qin Dynasty over 2200 years ago – bronze crossbow triggers and locking mechanisms were mass-produced and made to be interchangeable. Venice during the late Middle Ages had ships that were produced using pre-manufactured parts, assembly lines, and mass production | https://en.wikipedia.org/wiki?curid=376998 | 508,676 |
Quarter-wave impedance transformer A quarter-wave impedance transformer, often written as λ/4 impedance transformer, is a transmission line or waveguide used in electrical engineering of length one-quarter wavelength (λ), terminated with some known impedance. It presents at its input the dual of the impedance with which it is terminated. It is a similar concept to a stub; but, whereas a stub is terminated in a short (or open) circuit and the length is chosen so as to produce the required impedance, the λ/4 transformer is the other way around; it is a pre-determined length and the termination is designed to produce the required impedance. The relationship between the characteristic impedance, "Z", input impedance, "Z" and load impedance, "Z" is: formula_1 At radio frequencies of upper VHF or higher up to microwave frequencies one quarter wavelength is conveniently short enough to incorporate the component within many products, but not so small that it cannot be manufactured using normal engineering tolerances, and it is at these frequencies where the device is most often encountered. It is especially useful for making an inductor out of a capacitor, since designers have a preference for the latter. Another application is when DC power needs to be fed into a transmission line, which may be necessary to power an active device connected to the line, such as a switching transistor or a varactor diode for instance | https://en.wikipedia.org/wiki?curid=19202623 | 118,569 |
Multiplex ligation-dependent probe amplification (MLPA) is a variation of the multiplex polymerase chain reaction that permits amplification of multiple targets with only a single primer pair. It detects copy number changes at the molecular level, and software programs are used for analysis. Identification of deletions or duplications can indicate pathogenic mutations, thus MLPA is an important diagnostic tool used in clinical pathology laboratories worldwide. Each probe consists of two oligonucleotides which recognize adjacent target sites on the DNA. One probe oligonucleotide contains the sequence recognized by the forward primer, the other contains the sequence recognized by the reverse primer. Only when both probe oligonucleotides are hybridized to their respective targets, can they be ligated into a complete probe. The advantage of splitting the probe into two parts is that only the ligated oligonucleotides, but not the unbound probe oligonucleotides, are amplified. If the probes were not split in this way, the primer sequences at either end would cause the probes to be amplified regardless of their hybridization to the template DNA, and the amplification product would not be dependent on the number of target sites present in the sample DNA. Each complete probe has a unique length, so that its resulting amplicons can be separated and identified by (capillary) electrophoresis. This avoids the resolution limitations of multiplex PCR | https://en.wikipedia.org/wiki?curid=9346573 | 153,310 |
Marginal revenue If demand is elastic ("e" < –1) MR will be positive, because the additional unit would not drive down the price by so much. If the firm is a perfect competitor, so that it is so small in the market that its quantity produced and sold has no effect on the price, then the price elasticity of demand is negative infinity, and marginal revenue simply equals the (market-determined) price. Profit maximization requires that a firm produces where marginal revenue equals marginal costs. Firm managers are unlikely to have complete information concerning their marginal revenue function or their marginal costs. However, the profit maximization conditions can be expressed in a “more easily applicable form”: Markup is the difference between price and marginal cost. The formula states that markup as a percentage of price equals the negative (and hence the absolute value) of the inverse of the elasticity of demand. (P - MC)/ P = –1/e is called the Lerner index after economist Abba Lerner. The Lerner index is a measure of market power — the ability of a firm to charge a price that exceeds marginal cost. The index varies from zero (when demand is infinitely elastic (a perfectly competitive market) to 1 (when demand has an elasticity of –1). The closer the index value is to 1, the greater is the difference between price and marginal cost. The Lerner index increases as demand becomes less elastic. Alternatively, the relationship can be expressed as: Thus, for example, if "e" is –2 and MC is $5.00 then price is $10.00 | https://en.wikipedia.org/wiki?curid=1280458 | 514,536 |
Electronic circuit simulation These variations can be small, but taken together can change the output of a chip significantly. Temperature variation can also be modeled to simulate the circuit's performance through temperature ranges. | https://en.wikipedia.org/wiki?curid=10900720 | 403,159 |
Rossby wave Rossby waves, also known as planetary waves, are a type of inertial wave naturally occurring in rotating fluids. They were first identified by Carl-Gustaf Arvid Rossby. They are observed in the atmospheres and oceans of planets owing to the rotation of the planet. Atmospheric" Rossby waves on Earth are giant meanders in high-altitude winds that have a major influence on weather. These waves are associated with pressure systems and the jet stream. Oceanic" Rossby waves move along the thermocline: the boundary between the warm upper layer and the cold deeper part of the ocean. Atmospheric Rossby waves result from the conservation of potential vorticity and are influenced by the Coriolis force and pressure gradient. The rotation causes fluids to turn to the right as they move in the northern hemisphere and to the left in the southern hemisphere. For example, a fluid that moves from the equator toward the north pole will deviate toward the east; a fluid moving toward the equator from the north will deviate toward the west. These deviations are caused by the Coriolis force and conservation of potential vorticity which leads to changes of relative vorticity. This is analogous to conservation of angular momentum in mechanics. In planetary atmospheres, including Earth, Rossby waves are due to the variation in the Coriolis effect with latitude. Carl-Gustaf Arvid Rossby first identified such waves in the Earth's atmosphere in 1939 and went on to explain their motion | https://en.wikipedia.org/wiki?curid=438602 | 339,163 |
Computer ethics He argued that deciding is a computational activity while making choices is not and thus the ability to make choices is what makes us humans. At a later time during the same year Abbe Mowshowitz, a professor of Computer Science at the City College of New York, published an article titled "On approaches to the study of social issues in computing." This article identified and analyzed technical and non-technical biases in research on social issues present in computing. During 1978, the Right to Financial Privacy Act was adopted by the United States Congress, drastically limiting the government's ability to search bank records. During the next year Terrell Ward Bynum, the professor of Philosophy at Southern Connecticut State University as well as Director of the Research Center on Computing and Society there, developed curriculum for a university course on computer ethics. Bynum was also editor of the journal "Metaphilosophy." In 1983 the journal held an essay contest on the topic of computer ethics and published the winning essays in its best-selling 1985 special issue, “Computers and Ethics.” In 1984, the United States Congress passed the Small Business Computer Security and Education Act, which created a Small Business Administration advisory council to focus on computer security related to small businesses | https://en.wikipedia.org/wiki?curid=1408956 | 260,858 |
Cholesterol The main regulatory mechanism is the sensing of intracellular cholesterol in the endoplasmic reticulum by the protein SREBP (sterol regulatory element-binding protein 1 and 2). In the presence of cholesterol, SREBP is bound to two other proteins: SCAP (SREBP cleavage-activating protein) and INSIG-1. When cholesterol levels fall, INSIG-1 dissociates from the SREBP-SCAP complex, which allows the complex to migrate to the Golgi apparatus. Here SREBP is cleaved by S1P and S2P (site-1 protease and site-2 protease), two enzymes that are activated by SCAP when cholesterol levels are low. The cleaved SREBP then migrates to the nucleus, and acts as a transcription factor to bind to the sterol regulatory element (SRE), which stimulates the transcription of many genes. Among these are the low-density lipoprotein (LDL) receptor and HMG-CoA reductase. The LDL receptor scavenges circulating LDL from the bloodstream, whereas HMG-CoA reductase leads to an increase of endogenous production of cholesterol. A large part of this signaling pathway was clarified by Dr. Michael S. Brown and Dr. Joseph L. Goldstein in the 1970s. In 1985, they received the Nobel Prize in Physiology or Medicine for their work. Their subsequent work shows how the SREBP pathway regulates expression of many genes that control lipid formation and metabolism and body fuel allocation. synthesis can also be turned off when cholesterol levels are high | https://en.wikipedia.org/wiki?curid=6437 | 186,087 |
In situ capping of subaqueous waste It is important to know all of the regulatory standards in place for the desired location of the ISC. All ISC must comply with the requirements in the Resource Conservation and Recovery Act (RCRA) and the Toxic Substances Control Act (TSCA), although the ability of in-situ capping to meet those standards in the long term has not been successfully researched and studied enough due to lack of data. Cap design, which includes the composition and dimensions of the components, is probably the most important aspect of in-situ capping. The cap designs “must be compatible with available construction and placement techniques” along with meeting the three previously mentioned criteria above. The cap designs usually are over small areas with small volumes of contaminants. The cap is usually constructed with many layers of granular media, armor stone, and geotextiles. Presently, laboratory tests and models of the various processes involved (advection, diffusion, bioturbation, consolidation, erosion), limited field experience, and monitoring data drive cap design. Since data and field experience is limited a conservative approach is used when designing an in-situ cap. This approach uses the idea that the many different components are additive and no cap component provides a dual function, although a component may provide a dual function in actual practice. The six general steps for in-situ cap design, provided by Palermo et al | https://en.wikipedia.org/wiki?curid=25256459 | 325,182 |
Pirate radio The navy took it a step further and declared it was illegal to listen to radio or possess a receiver or transmitter in the US, but there were doubts they had the authority to issue such an order even in war time. The ban on radio was lifted in the US in late 1919. In 1924, New York City station WHN was accused by the American Telephone and Telegraph Company (AT&T) of being an "outlaw station" for violating trade licenses which permitted only AT&T stations to sell airtime on their transmitters. As a result of the AT&T interpretation a landmark case was heard in court, which even prompted comments from Secretary of Commerce Herbert Hoover when he took a public stand in the station's defense. Although AT&T won its case, the furor created was such that those restrictive provisions of the transmitter license were never enforced. In 1926, WJAZ in Chicago changed its frequency to one previously reserved for Canadian stations without getting permission to make the change, and was charged by the federal government with "wave piracy". The resulting legal battle found that the Radio Act of 1912 did not allow the U.S. government to require stations to operate on specific frequencies, and the result was the passage of the Radio Act of 1927 to strengthen the government's regulatory authority. While Mexico issued radio station XERF with a license to broadcast, the power of its 250 kW transmitter was far greater than the maximum of 50 kW authorized for commercial use by the government of the United States of America | https://en.wikipedia.org/wiki?curid=175990 | 499,102 |
Bethlem Royal Hospital Problems with the building were soon noted as the steam heating did not function properly, the basement galleries were damp and the windows of the upper storeys were unglazed "so that the sleeping cells were either exposed to the full blast of cold air or were completely darkened". Although glass was placed in the windows in 1816, the Governors initially supported their decision to leave them unglazed on the basis that it provided ventilation and so prevented the build-up of "the disagreable effluvias peculiar to all madhouses". Faced with increased admissions and overcrowding, new buildings, designed by the architect Sydney Smirke, were added from the 1830s. The wing for criminal lunatics was increased to accommodate a further 30 men while additions to the east and west wings, extending the building's facade, provided space for an additional 166 inmates and a dome was added to the hospital chapel. At the end of this period of expansion Bethlem had a capacity for 364 patients. The late eighteenth and early nineteenth centuries are typically seen as decisive in the emergence of new attitudes towards the management and treatment of the insane. Increasingly, the emphasis shifted from the external control of the mad through physical restraint and coercion to their moral management whereby self-discipline would be inculcated through a system of reward and punishment | https://en.wikipedia.org/wiki?curid=373047 | 309,176 |
Quintuple bond In 2007 the shortest-ever metal–metal bond (180.28 pm) was reported to exist also in a compound containing a quintuple chromium-chromium bond with diazadiene bridging ligands. Other metal–metal quintuple bond containing complexes that have been reported include quintuply bonded dichromium with [6-(2,4,6-triisopropylphenyl)pyridin-2-yl](2,4,6-trimethylphenyl)amine bridging ligands and a dichromium complex with amidinate bridging ligands. Synthesis of quintuple bonds is usually achieved through reduction of a dimetal species using potassium graphite. This adds valence electrons to the metal centers, giving them the needed number of electrons to participate in quintuple bonding. Below is a figure of a typical quintuple bond synthesis. In 2009 a dimolybdenum compound with a quintuple bond and two diamido bridging ligands was reported with a Mo–Mo bond length of 202 pm. The compound was synthesised starting from potassium octachlorodimolybdate (which already contains a Mo quadruple bond) and a lithium amidinate, followed by reduction with potassium graphite: As stated above metal-metal quintuple bonds have a σπδ configuration. Among the five bonds present between the metal centers, one is a sigma bond, two are pi bonds, and two are delta bonds. The σ-bond is the result of mixing between the d orbital on each metal center. The first π-bond comes from mixing of the d orbitals from each metal while the other π-bond comes from the d orbitals on each metal mixing | https://en.wikipedia.org/wiki?curid=2779670 | 22,342 |
Ion track Negative surface charges can be occupied by firmly bound protons. At low pH (high proton concentration), the wall charge is completely neutralized. Surface conductivity vanishes. Due to the dependence of surface conductivity on pH, the channel becomes a pH sensor. Current rectifying pores: Asymmetric pores are obtained by one-sided etching. The geometric asymmetry translates into a conduction asymmetry. The phenomenon is similar to an electrical valve. The pore has two characteristic conduction states, open and closed. Above a certain voltage the valve opens. Below a certain voltage the valve closes. Thermo-responsive channel: Obtained by lining a channel with a thermo-responsive gel. Bio-sensor: Chemical modification of the channel wall changes its interaction with passing particles. Different wall claddings bind to specific molecules and delay their passage. In this sense, the wall "recognizes" the passing particle. As an example, DNA fragments are selectively bound by their complementary fragments. The attached molecules reduce the channel volume. The induced resistance change reflects the molecule's concentration. Anisotropic conduction: A platform covered with many free standing wires acts as large area field emitter. Magnetic multilayers: Nano-wires consisting of alternating magnetic/nonmagnetic layers act as magnetic sensors. As an example, cobalt/copper nanowires are obtained from an electrolyte containing both metals. At low voltage, pure copper is deposited while cobalt resists electro-deposition | https://en.wikipedia.org/wiki?curid=33558290 | 77,127 |
International Marine Contractors Association IMCA has developed a comprehensive body of knowledge in the form of a suite of over 250 published guidance documents, technical information notes, DVDs and safety promotional materials which are internationally recognised as authoritative and establish standards of good practice in the marine contracting industry. IMCA has published guidance documents in the following fields: IMCA provides an internationally recognised certification scheme for three specialist diving disciplines: IMCA organises an annual programme of meetings and events all over the world, including regional meetings, briefing sessions, technical seminars and workshops on specific industry related issues. The Association's flagship event takes place every two years with an agenda combining business and strategic issues featuring senior executives and technical sessions. IMCA also supports a number of conferences and exhibitions hosted by other organisations which share a common interest of its members. | https://en.wikipedia.org/wiki?curid=19985865 | 220,835 |
Biotechnology and genetic engineering in Bangladesh In September 1993, the government of Bangladesh formed a National Committee on Biotechnology Product Development to select potential biotechnological projects which could be leased out for commercialisation. In collaboration with BAPTC, the Ministry of Science and Technology organised a workshop on Biosafety Regulation in 1997, after which a task force was formed to formulate biosafety guidelines and biosafety regulations in the light of the regulation of the workshop. In the late 1990s, Bangladesh became a member of the International Centre for Genetic Engineering and Biotechnology (ICGEB). In 1999, the National Institute of Biotechnology was established as the centre of excellence in biotechnological education. To accelerate multidimensional biotechnological research, in 2006, the government adopted the national policy guidelines on biotechnology which was approved by the National Task force on biotechnology. In 2012, the cabinet approved the draft of "National Biotechnology Policy, 2012" which was aimed at eradicating poverty through increasing productivity in agriculture and industrial sectors. In 2008, with the funding of the government, the University of Dhaka, DataSoft IT firm and Bangladesh Jute Research Institute initiated a collaborative genome research program on jute under the leadership of Dr. Maqsudul Alam who had previously sequenced the genomes of papaya and rubber | https://en.wikipedia.org/wiki?curid=39882238 | 221,965 |
Stochastic drift In probability theory, stochastic drift is the change of the average value of a stochastic (random) process. A related concept is the drift rate, which is the rate at which the average changes. For example, a process that counts the number of heads in a series of formula_1 fair coin tosses has a drift rate of 1/2 per toss. This is in contrast to the random fluctuations about this average value. The stochastic mean of that coin-toss process is 1/2 and the drift rate of the stochastic mean is 0, assuming 1=heads and 0=tails. Longitudinal studies of secular events are frequently conceptualized as consisting of a trend component fitted by a polynomial, a cyclical component often fitted by an analysis based on autocorrelations or on a Fourier series, and a random component (stochastic drift) to be removed. In the course of the time series analysis, identification of cyclical and stochastic drift components is often attempted by alternating autocorrelation analysis and differencing of the trend. Autocorrelation analysis helps to identify the correct phase of the fitted model while the successive differencing transforms the stochastic drift component into white noise. can also occur in population genetics where it is known as genetic drift. A "finite" population of randomly reproducing organisms would experience changes from generation to generation in the frequencies of the different genotypes. This may lead to the fixation of one of the genotypes, and even the emergence of a new species | https://en.wikipedia.org/wiki?curid=2486019 | 513,684 |
Motherboard Prior to the invention of the microprocessor, the digital computer consisted of multiple printed circuit boards in a card-cage case with components connected by a backplane, a set of interconnected sockets. In very old designs, copper wires were the discrete connections between card connector pins, but printed circuit boards soon became the standard practice. The Central Processing Unit (CPU), memory, and peripherals were housed on individual printed circuit boards, which were plugged into the backplane. The ubiquitous S-100 bus of the 1970s is an example of this type of backplane system. The most popular computers of the 1980s such as the Apple II and IBM PC had published schematic diagrams and other documentation which permitted rapid reverse-engineering and third-party replacement motherboards. Usually intended for building new computers compatible with the exemplars, many motherboards offered additional performance or other features and were used to upgrade the manufacturer's original equipment. During the late 1980s and early 1990s, it became economical to move an increasing number of peripheral functions onto the motherboard. In the late 1980s, personal computer motherboards began to include single ICs (also called Super I/O chips) capable of supporting a set of low-speed peripherals: keyboard, mouse, floppy disk drive, serial ports, and parallel ports | https://en.wikipedia.org/wiki?curid=19945 | 419,329 |
Electricity market These criteria have been largely adopted in the US, Australia, New Zealand and Singapore. The system price in the day-ahead market is, in principle, determined by matching offers from generators to bids from consumers at each node to develop a classic supply and demand equilibrium price, usually on an hourly interval, and is calculated separately for subregions in which the system operator's load flow model indicates that constraints will bind transmission imports. The theoretical prices of electricity at each node on the network is a calculated "shadow price", in which it is assumed that one additional kilowatt-hour is demanded at the node in question, and the hypothetical incremental cost to the system that would result from the optimized redispatch of available units establishes the hypothetical production cost of the hypothetical kilowatt-hour. This is known as "locational marginal pricing" (LMP) or "nodal pricing" and is used in some deregulated markets, most notably in the Midcontinent Independent System Operator, PJM Interconnection, ERCOT, New York, and New England markets in the US, New Zealand, and in Singapore. In practice, the LMP algorithm described above is run, incorporating a security-constrained, least-cost dispatch calculation (see below) with supply based on the generators that submitted offers in the day-ahead market, and demand based on bids from load-serving entities draining supplies at the nodes in question | https://en.wikipedia.org/wiki?curid=215909 | 394,805 |
Biochemistry More recently, Andrew Z. Fire and Craig C. Mello received the 2006 Nobel Prize for discovering the role of RNA interference (RNAi), in the silencing of gene expression. Around two dozen chemical elements are essential to various kinds of biological life. Most rare elements on Earth are not needed by life (exceptions being selenium and iodine), while a few common ones (aluminum and titanium) are not used. Most organisms share element needs, but there are a few differences between plants and animals. For example, ocean algae use bromine, but land plants and animals seem to need none. All animals require sodium, but some plants do not. Plants need boron and silicon, but animals may not (or may need ultra-small amounts). Just six elements—carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus—make up almost 99% of the mass of living cells, including those in the human body (see composition of the human body for a complete list). In addition to the six major elements that compose most of the human body, humans require smaller amounts of possibly 18 more. The four main classes of molecules in biochemistry (often called biomolecules) are carbohydrates, lipids, proteins, and nucleic acids. Many biological molecules are polymers: in this terminology, monomers are relatively small macromolecules that are linked together to create large macromolecules known as polymers. When monomers are linked together to synthesize a biological polymer, they undergo a process called dehydration synthesis | https://en.wikipedia.org/wiki?curid=3954 | 296,284 |
Action potential Action potentials cannot propagate through the membrane in myelinated segments of the axon. However, the current is carried by the cytoplasm, which is sufficient to depolarize the first or second subsequent node of Ranvier. Instead, the ionic current from an action potential at one node of Ranvier provokes another action potential at the next node; this apparent "hopping" of the action potential from node to node is known as saltatory conduction. Although the mechanism of saltatory conduction was suggested in 1925 by Ralph Lillie, the first experimental evidence for saltatory conduction came from Ichiji Tasaki and Taiji Takeuchi and from Andrew Huxley and Robert Stämpfli. By contrast, in unmyelinated axons, the action potential provokes another in the membrane immediately adjacent, and moves continuously down the axon like a wave. Myelin has two important advantages: fast conduction speed and energy efficiency. For axons larger than a minimum diameter (roughly 1 micrometre), myelination increases the conduction velocity of an action potential, typically tenfold. Conversely, for a given conduction velocity, myelinated fibers are smaller than their unmyelinated counterparts. For example, action potentials move at roughly the same speed (25 m/s) in a myelinated frog axon and an unmyelinated squid giant axon, but the frog axon has a roughly 30-fold smaller diameter and 1000-fold smaller cross-sectional area | https://en.wikipedia.org/wiki?curid=156998 | 181,496 |
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