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Market engineering
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Process
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Implementation In this stage, the thoroughly evaluated design is realized and implemented as a software system. The market system can either be implemented from scratch or the prototype developed in the evaluation stage can be enhanced in an evolutionary process. This phase is supported by traditional software engineering concepts and tools, such as UML, design patterns, or the Rational Unified Process. The output of this phase is a fully implemented electronic market with the institutional rules and the business model.
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Market engineering
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Process
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Introduction In the last stage of the process, the electronic market is introduced. The introduction of the electronic market initiates its operation cycle.
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Market engineering
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Computer-aided market engineering
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The Computer-Aided Market Engineering (CAME) tool suite meet2trade showcases a service engineering approach to the development of electronic markets as a service offering (Weinhardt et al. 2006, Neumann et al. 2005). For e-markets, the market operator—as service provider decides the following prerequisites that characterize the complex service: the products that will be traded; the market rules to match demand and supply; the IT infrastructure of the trading platform; the business structure trefies defining the value proposition; and the business model to derive revenue from the service offering.
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Market engineering
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Computer-aided market engineering
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The CAME tool suite provides a conceptual framework for designing e-markets, a process model to guide the design, and methods and tools supporting these design steps. These tasks are inherently interdisciplinary. The strategic task of defining the segment, in which the e-market is intended to operate, is primarily a management and marketing endeavor. The design of the market mechanisms that describe the flow of the negotiation process, pertains to economics. Implementing the market mechanisms as a running service system is mainly a software engineering task.
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Market engineering
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Computer-aided market engineering
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The CAME approach extends state-of-the-art methods, as it tackles all problems associated with the design of e-markets holistically. For example, Knowledge-based Auction Design Support (KADS) enables the market operator to decide on the principal auction format. Auction Runtime Environment (ARTE) and Adaptive Client (AC) support the transformation of the concept into an instantiation of a running auction format, supporting embodiment and detail design. Lastly, Agent-based Simulation Environment (AMASE) and Experimental System (MES) provide extensive testing functionalities. Prototypes can be generated and tested on-the-fly, improving the design process considerably.
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Market engineering
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Computer-aided market engineering
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This research work focuses on how to design and operate market services, how to gain knowledge for this task, and how to provide this knowledge to those who need to set up auctions, exchanges, or e-procurement platforms. CAME epitomizes an SSME approach and meet2trade workbench showcases an integrated outcome of service sciences, management, and engineering.
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Market engineering
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Literature
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Kolitz, K. and C. Weinhardt (2006). MES - Ein Experimentalsystem zur Untersuchung elektronischer Märkte. MKWI 2006, Passau, Germany.
Neumann, D. (2004). Market Engineering - A Structured Design Process for Electronic Markets. Fakultät für Wirtschaftswissenschaften. Karlsruhe, Universität Karlsruhe (TH).
Neumann, D., J. Maekioe, et al. (2005). CAME - A Toolset for Configuring Electronic Markets. ECIS, Regensburg.
Roth, A. E. (2000). Game Theory as a Tool for Market Design. Game Practice: Contributions from Applied Game Theory. F. Patrone, I. Garcia-Jurado and S. Tijs. Dordrecht, Kluwer: 7-18.
Roth, A. E. (2002). "The Economist as Engineer: Game Theory, Experimental Economics and Computation as Tools for Design Economics". Econometrica. 70 (4): 1341–1378. CiteSeerX 10.1.1.61.3706. doi:10.1111/1468-0262.00335.
Smith, V. (2003). Markets, Institutions and Experiments. Encyclopedia of Cognitive Science. L. Nadel. London, Nature Publishing Group. 2: 991-998.
Weinhardt, C.; Holtmann, C.; et al. (2003). "Market Engineering". Wirtschaftsinformatik. 45 (6): 635–640. doi:10.1007/bf03250926. S2CID 218840818.
Weinhardt, C.; Neumann, D.; et al. (2006). "Computer-aided Market Engineering". Communications of the ACM. 49 (7): 79. doi:10.1145/1139922.1139953. S2CID 19352393.
Wurman, Wellman and Walsh (1998). "The Michigan Internet AuctionBot: A Configurable Auction Server for Human and Software Agents" (Proceedings of the 2nd International Conference on Autonomous Agents)
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Rotavirus cis-acting replication element
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Rotavirus cis-acting replication element
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This family represents a rotavirus cis-acting replication element (CRE) found at the 3'-end of rotavirus mRNAs. The family is thought to promote the synthesis of minus strand RNA to form viral dsRNA.
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Pokémon DS
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Pokémon DS
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Pokémon DS may refer to these video games in the Pokémon series for Nintendo DS. It is widely accepted as the peak of Pokémon.
Pokémon Diamond and Pearl Pokémon Platinum Pokémon HeartGold and SoulSilver Pokémon Black and White Pokémon Black 2 and White 2 Pokémon Ranger Pokémon Ranger: Shadows of Almia Pokémon Ranger: Guardian Signs Pokémon Mystery Dungeon: Blue Rescue Team Pokémon Mystery Dungeon: Explorers of Time and Explorers of Darkness Pokémon Mystery Dungeon: Explorers of Sky Pokémon Dash Pokémon Trozei!
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Geometric complexity theory
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Geometric complexity theory
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Geometric complexity theory (GCT), is a research program in computational complexity theory proposed by Ketan Mulmuley and Milind Sohoni. The goal of the program is to answer the most famous open problem in computer science – whether P = NP – by showing that the complexity class P is not equal to the complexity class NP.
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Geometric complexity theory
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Geometric complexity theory
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The idea behind the approach is to adopt and develop advanced tools in algebraic geometry and representation theory (i.e., geometric invariant theory) to prove lower bounds for problems. Currently the main focus of the program is on algebraic complexity classes. Proving that computing the permanent cannot be efficiently reduced to computing determinants is considered to be a major milestone for the program. These computational problems can be characterized by their symmetries. The program aims at utilizing these symmetries for proving lower bounds.
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Geometric complexity theory
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Geometric complexity theory
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The approach is considered by some to be the only viable currently active program to separate P from NP. However, Ketan Mulmuley believes the program, if viable, is likely to take about 100 years before it can settle the P vs. NP problem.The program is pursued by several researchers in mathematics and theoretical computer science. Part of the reason for the interest in the program is the existence of arguments for the program avoiding known barriers such as relativization and natural proofs for proving general lower bounds.
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Conservation biology of parasites
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Conservation biology of parasites
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A large proportion of living species on Earth live a parasitic way of life. Parasites have traditionally been seen as targets of eradication efforts, and they have often been overlooked in conservation efforts. In the case of parasites living in the wild – and thus harmless to humans and domesticated animals – this view is changing. The conservation biology of parasites is an emerging and interdisciplinary field that recognizes the integral role parasites play in ecosystems. Parasites are intricately woven into the fabric of ecological communities, with diverse species occupying a range of ecological niches and displaying complex relationships with their hosts.
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Conservation biology of parasites
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Conservation biology of parasites
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The rationale for parasite conservation extends beyond their intrinsic value and ecological roles. Parasites offer potential benefits to human health and well-being. Many parasites produce bioactive compounds with pharmaceutical properties, which can be utilized in drug discovery and development. Understanding and conserving parasite biodiversity not only contributes to the preservation of ecosystems but also holds promise for medical advancements and novel therapeutic interventions.
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Conservation biology of parasites
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Parasite role in ecosystems
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Ranging from microscopic pathogens to larger organisms such as worms and arthropods, parasites exhibit remarkable diversity in their life cycles, transmission strategies, and host relationships. They can be found in virtually every ecosystem on Earth, including terrestrial, freshwater, and marine environments. Parasites often rely on one or multiple host species to complete their life cycle, and their presence can have profound effects on host populations, communities, and even entire ecosystems. One of the fundamental aspects of parasite ecology is their role as a trophic level within the food web. Parasites can occupy various positions within the trophic hierarchy, acting as predators, consumers, or even decomposers. They regulate host populations by influencing host behavior, growth, and reproduction. Furthermore, parasites can indirectly shape community dynamics by mediating interactions between host species and influencing the distribution and abundance of other organisms within the ecosystem.Despite their ecological significance, parasites have historically received less attention in conservation efforts compared to other groups of organisms. However, in recent years, there has been a growing recognition of the importance of parasite conservation. Ecologists and conservation biologists have emphasized the need for research to understand the ecological roles of parasites, as well as the threats they face and the potential consequences of their decline or extinction. Integrating parasite conservation into broader conservation frameworks is crucial for maintaining the integrity and functionality of ecosystems.
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Conservation biology of parasites
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Conservation approaches
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Conservation approaches for animal parasites encompass a range of strategies tailored to their unique characteristics and conservation requirements. Assessing the conservation status of parasites poses challenges, as traditional criteria such as those developed by the IUCN may not adequately capture the specific threats and vulnerabilities of these organisms. Efforts often focus on conserving host species, recognizing that protecting the host also benefits associated parasites. This includes habitat conservation, management of host populations, and minimizing anthropogenic impacts.Nuances arise in parasite conservation when considering translocating species or implementing captive breeding programs. It is essential to consider the potential effects on parasite populations and ensure that appropriate measures are in place to safeguard their survival. In situ conservation, which involves the preservation and management of parasites within their natural habitats, is a key approach. Additionally, ex situ conservation methods, such as maintaining parasite populations in controlled environments, can serve as a safety net for critically endangered species.
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Conservation biology of parasites
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Endangered parasite species
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A note published in 1990 pointed out that the captive breeding and reintroduction program to save the black-footed ferret would cause the loss of its specific parasites and demanded "equal rights for parasites". A paper in 1992 warned that not only the loss of certain host species from the wild, but host population bottlenecks or the fragmentation of host populations would predictably lead to the extinction of host-specific parasites. The paper also noted that parasites exert selective pressures upon their host populations that increase host genetic diversity. At first, this view met with open scepticism. However, it became clear that the co-extinction of hosts and their specific parasites is likely to increase the current estimates of extinction rates significantly. A decade later, a study focusing on highly host-specific groups such as fig wasps, parasites, butterflies, and myrmecophil butterflies estimated the number of parasites put at risk by the endangered status of the host at about 6300. Other authors argued that host-specific parasite faunae have an unexpected advantage for conservation scientists. Their genealogies and population genetic patterns may help to illuminate their hosts' evolutionary and demographic history. Recently, scientists suggested that rich parasite faunae are inevitably needed for healthy ecosystem functioning and also that parasites and mutualists are the most endangered species on Earth. Even vets have started to argue about the conservational values of parasite species.A recent study on parasites of coral reef fish suggested that extinction of a coral reef fish species would eventually result in the coextinction of at least ten species of parasites. Although this number might seem high, the study included only large parasites such as parasitic worms and crustaceans, but not microparasites such as Myxosporea and Microsporidia.
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Conservation biology of parasites
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Examples of parasite conservation
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The list below follows that of Mey (2005) Acutifrons caracarensis parasite of the extinct Guadalupe caracara (Caracara lutosa), Guadalupe Island, Mexico; Longimenopon dominicanum parasite of the extinct Guadalupe storm petrel, Oceanodroma macrodactyla, Guadelupe Island, Mexico; Rallicola piageti parasite of the possibly extinct New Caledonian rail (Gallirallus lafresnayanus), New Caledonia; Coloceras hemiphagae parasite of the extinct Norfolk Island pigeon (Hemiphaga novaeseelandiae spadicea), Norfolk Island, New Zealand; Coloceras restinctus parasite of the extinct Norfolk Island pigeon (Hemiphaga novaeseelandiae spadicea), Norfolk Island, New Zealand; Rallicola extinctus parasite of the extinct huia (Heteralocha acutirostris), New Zealand; Philopteroides xenicus parasite of the extinct bushwren (Xenicus longipes), New Zealand; Psittacobrosus bechsteini parasite of the extinct Cuban red macaw (Ara tricolor), Cuba; Colpocephalum californici, parasite of the California condor (Gymnogyps californianus). The host was saved by a captive breeding and repatriation program, but the parasite was lost, deliberately killed whenever it was found during the program.Additionally, Columbicola extinctus is a parasite of the extinct passenger pigeon (Ectopistes migratorius). However, recent taxonomic studies show that it is conspecific with the lice living on band-tailed pigeon (Columba fasciata), thus it is not extinct.
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Equalization (communications)
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Equalization (communications)
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In telecommunication, equalization is the reversal of distortion incurred by a signal transmitted through a channel. Equalizers are used to render the frequency response—for instance of a telephone line—flat from end-to-end. When a channel has been equalized the frequency domain attributes of the signal at the input are faithfully reproduced at the output. Telephones, DSL lines and television cables use equalizers to prepare data signals for transmission.
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Equalization (communications)
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Equalization (communications)
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Equalizers are critical to the successful operation of electronic systems such as analog broadcast television. In this application the actual waveform of the transmitted signal must be preserved, not just its frequency content. Equalizing filters must cancel out any group delay and phase delay between different frequency components.
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Equalization (communications)
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Analog telecommunications
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Audio lines Early telephone systems used equalization to correct for the reduced level of high frequencies in long cables, typically using Zobel networks. These kinds of equalizers can also be used to produce a circuit with a wider bandwidth than the standard telephone band of 300 Hz to 3.4 kHz. This was particularly useful for broadcasters who needed "music" quality, not "telephone" quality on landlines carrying program material. It is necessary to remove or cancel any loading coils in the line before equalization can be successful. Equalization was also applied to correct the response of the transducers, for example, a particular microphone might be more sensitive to low frequency sounds than to high frequency sounds, so an equalizer would be used to increase the volume of the higher frequencies (boost), and reduce the volume of the low frequency sounds (cut).
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Equalization (communications)
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Analog telecommunications
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Television lines A similar approach to audio was taken with television landlines with two important additional complications. The first of these is that the television signal is a wide bandwidth covering many more octaves than an audio signal. A television equalizer consequently typically requires more filter sections than an audio equalizer. To keep this manageable, television equalizer sections were often combined into a single network using ladder topology to form a Cauer equalizer.
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Equalization (communications)
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Analog telecommunications
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The second issue is that phase equalization is essential for an analog television signal. Without it dispersion causes the loss of integrity of the original wave-shape and is seen as smearing of what were originally sharp edges in the picture.
Analog equalizer types Zobel network Lattice phase equalizer Bridged T delay equalizer
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Equalization (communications)
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Digital telecommunications
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Modern digital telephone systems have less trouble in the voice frequency range as only the local line to the subscriber now remains in analog format, but DSL circuits operating in the MHz range on those same wires may suffer severe attenuation distortion, which is dealt with by automatic equalization or by abandoning the worst frequencies. Picturephone circuits also had equalizers.
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Equalization (communications)
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Digital telecommunications
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In digital communications, the equalizer's purpose is to reduce intersymbol interference to allow recovery of the transmit symbols. It may be a simple linear filter or a complex algorithm.
Digital equalizer types Linear equalizer: processes the incoming signal with a linear filter MMSE equalizer: designs the filter to minimize E[|e|2], where e is the error signal, which is the filter output minus the transmitted signal.
Zero-forcing equalizer: approximates the inverse of the channel with a linear filter.
Decision feedback equalizer: augments a linear equalizer by adding a filtered version of previous symbol estimates to the original filter output.
Blind equalizer: estimates the transmitted signal without knowledge of the channel statistics, using only knowledge of the transmitted signal's statistics.
Adaptive equalizer: is typically a linear equalizer or a DFE. It updates the equalizer parameters (such as the filter coefficients) as it processes the data. Typically, it uses the MSE cost function; it assumes that it makes the correct symbol decisions, and uses its estimate of the symbols to compute e, which is defined above.
Viterbi equalizer: Finds the maximum likelihood (ML) optimal solution to the equalization problem. Its goal is to minimize the probability of making an error over the entire sequence.
BCJR equalizer: uses the BCJR algorithm (also called the Forward-backward algorithm) to find the maximum a posteriori (MAP) solution. Its goal is to minimize the probability that a given bit was incorrectly estimated.
Turbo equalizer: applies turbo decoding while treating the channel as a convolutional code.
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Superimposed code
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Superimposed code
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A superimposed code such as Zatocoding is a kind of hash code that was popular in marginal punched-card systems.
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Superimposed code
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Marginal punched-card systems
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Many names, some of them trademarked, have been used for marginal punched-card systems: edge-notched cards, slotted cards, E-Z Sort, Zatocards, McBee, McBee Keysort, Flexisort, Velom, Rocket, etc.
The center of each card held the relevant information—typically the name and author of a book, research paper, or journal article on a nearby shelf; and a list of subjects and keywords.
Some sets of cards contained all the information required by the user on the card itself, handwritten, typewritten, or on microfilm (aperture card).
Every card in a stack had the same set of pre-punched holes.
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Superimposed code
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Marginal punched-card systems
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The user would find the particular cards relevant to a search by aligning the holes in the set of cards (using a card holder or card tray), inserting one or more knitting-needle-like rods all the way through the stack, so the desired cards (which had been notched or cut open) fell out from the irrelevant cards in the collection (left un-notched), which remain on the needle(s).
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Superimposed code
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Marginal punched-card systems
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A user could repeat this selection many times to form a complex Boolean searching query.
A card that was relevant to 2 or more subjects would have the slot(s) for each of those subjects cut out, so that card would drop out when either one or the other or both subjects was selected .
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Superimposed code
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Marginal punched-card systems
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The "superimposed code" coding systems, such as Zatocoding, saved space by entering several or all subjects in the same field; such a "superimposed code" stores much more information in less space, but at the cost of occasional "false" selections.Once you have a collection of index cards, one per book, research paper, or journal article in a library, with a list of keywords (subjects) discussed in a particular book written on that book's card, the "obvious way" to code those subjects is to count up the total number of subjects used in the entire collection R, make a row of R holes near the top of every card, and for each subject actually discussed in a particular book, cut a slot from the hole corresponding to that subject in the card corresponding to that book.
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Superimposed code
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Marginal punched-card systems
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Naturally, this also requires a separate list of every subject used in the collection that indicates which hole is punched for each subject.
Unfortunately, there may be thousands of distinct subjects in the collection, and it is impractical to punch thousands of holes in every card.
While it may not seem possible to use less than 1 hole per subject, superimposed code systems can solve this problem.
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Superimposed code
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Superimposed codes
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The Zatocoding system of information retrieval was developed by Calvin Mooers in 1947.Calvin Mooers invented Zatocoding at M.I.T., a mechanical information retrieval system based on superimposed codes, and formed the Zator Company in 1947 to commercialize its applications.
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Superimposed code
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Superimposed codes
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The particular superimposed code used in that system is called Zatocoding, while the marginal-punched card information retrieval system as a whole is called "Zator".Setting up a superimposed code for a particular library goes something like this: Going through every card in the index, a list of all R subjects used in this particular library is created, and the maximum number of subjects r actually written on a single card is noted. (For example, say we have 8000 subjects, and the librarian decides to index only the top r=4 subjects per book).
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Superimposed code
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Superimposed codes
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The librarian looks at the physical edge-notched card, and notes the number of holes N in each card. (If N >= R, then we could use the "obvious way" mentioned above—the whole point of Zatocoding is that it works even when N is much less than R).
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Superimposed code
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Superimposed codes
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The librarian chooses some number n of slots per subject—typically n=N(1−2−1r) On the list of all R subjects, for each subject write down which holes will be slotted for that subject. Rather than slotting one hole per subject in "the obvious way", a superimposed code will slot n holes per subject. (There are several ways to pick these patterns—those distinguish between the various superimposed codes; we discuss them below).
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Superimposed code
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Superimposed codes
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When a new book comes in, make a new card for it: Get a blank card with the standard N holes in it and write down the name of the book, etc. in the middle.
Write down the subjects covered by the book on the card.
For each of the top r subjects, look up that subject in the big list, and see which n slots to cut for that subject, and cut them.
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Superimposed code
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Superimposed codes
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When the card is finished, it may have up to r*n slots cut into it—but more likely at least some of the subject slot patterns overlapped, resulting in only v < r*n slots.Later, when we need to find books on some particular subject, we look up that subject in our list of all R subjects, find the corresponding slot pattern of n slots, and put n needles are through the whole stack in that pattern.
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Superimposed code
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Superimposed codes
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All of the cards that have been cut with that pattern will fall out.
It is possible that a few other, undesired cards may also fall out—cards who have several subjects whose hole patterns overlap in such a way as to mimic the desired pattern.
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Superimposed code
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Superimposed codes
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The probability F of some undesired card with v slots cut in it falling through when we select some pattern of n needles is approximately F=(vN)n Most systems have a N large enough and r small enough such that, v < N/2 (i.e., the card is less than half-punched), so that probability of an undesired card falling through is less than F<(12)n .There are several different ways to choose which holes will be slotted for each subject.
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Superimposed code
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Superimposed codes
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(Several variations of Zatocoding were developed. Bourne describes a variant "for newer retrieval systems that require high performance of the superimposed coding system", using an approach Mooers published in 1959.) Zatocoding Setting up a Zatocode for a particular list of R subjects goes something like this: For the first subject, pick n of the N slots randomly.
For the second subject, pick n of the N slots randomly—but make sure this pattern is not identical to the first subject.
...
For the R'th subject, pick n of the N slots randomly—but make sure it's not identical to any previous subject.
Other superimposed codes A Zatocode requires a code book that lists every subject and a randomly generated notch code associated with each one.
Other "direct" superimposed codes have a fixed hash function for transforming the letters in (one spelling of) a subject into a notch code.
Such codes require a much shorter code book that describes the translation of letters in a word to the corresponding notch code, and can in principle easily add new subjects without changing the code book.A Bloom filter can be considered a kind of superimposed code.
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Archives of Toxicology
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Archives of Toxicology
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Archives of Toxicology is a peer-reviewed medical journal covering all aspects of toxicology. It was established in 1930 as Sammlung von Vergiftungsfällen, renamed in 1954 into Archiv für Toxikologie and obtained its current title in 1974. The journal is published by Springer Science+Business Media and the editor-in-chief is Jan G. Hengstler (Leibniz Research Centre for Working Environment and Human Factors).
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Archives of Toxicology
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Abstracting and indexing
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The journal is abstracted and indexed in: According to the Journal Citation Reports, the journal has a 2020 impact factor of 5.153.
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Neuromuscular therapy
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Neuromuscular therapy
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Neuromuscular Therapy (NMT) is an approach to soft tissue manual therapy. It has been shown to be effective in the treatment of many conditions, although not all pathologies have shown treatment effects which persist over time.
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Sodium gluconate
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Sodium gluconate
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Sodium gluconate is a compound with formula NaC6H11O7. It is the sodium salt of gluconic acid. Its E number is E576. Sodium gluconate is widely used in textile dyeing, printing and metal surface water treatment. It is also used as a chelating agent, a steel surface cleaning agent, a cleaning agent for glass bottles, and as a chelating agent for cement, plating and alumina dyeing industries. It is a white powder that is very soluble in water.
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Lob wedge
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Lob wedge
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A lob wedge, also known as a lofted wedge or an L-Wedge, is a wedge used in the sport of golf, known for being one of the shortest-hitting clubs and providing the most loft on a shot. Lob wedges are used to produce shots with a very high arc, and are most often used for shots over hazards and other obstructions. Due to the high arc of the shot the lob wedge, like the other wedges in the set of irons, produces little roll after landing on the putting green and can even be used to produce backspin if necessary. Lob wedges are one of the newest additions to the modern collection of golf clubs and, along with the sand wedge and gap wedge, were not included prior to 1931.
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Lob wedge
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Design
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Lob wedges are part of the iron family of golf clubs and are designed for short, high arc shots. Lob wedges and ultra lob wedges are designed with the shortest shafts and the highest loft of all golf clubs. Regular lob wedges may come in a variety of lofts, usually starting around 56 degrees and approaching 60. While those above 60 degrees are rare, often up to 64 degrees, they do exist and are referred to as "x-wedges", extreme lob wedges, or ultra lob wedges. Other differences between the lob wedge and the rest of the wedge family include the less pronounced flange on the sole allowing the club to slide under the ball more easily and less degrees of bounce (often between 0–10 degrees). The low bounce was designed out of the necessity of professionals who found that the higher bounce sand wedge was making it difficult to produce the spin they desired, especially out of tight lies Ultra lob wedge An ultra lob wedge is used to hit a shot with higher and shorter trajectory than a standard lob wedge. This club is labeled "UL" and has a loft of about 64° and has the highest loft of any golf club. It is used for specialized, extremely high-angle shots such as from the "lip" of a bunker. This wedge is generally made by speciality companies and some argue that their purpose is redundant, as other wedges can be "opened" for extra loft in situations calling for such a high launch angle. Furthermore, to get consistent results, this club requires skill – in particular, distance judgment is always key with such a lofted club. It can be noted that different lengths of swing will often yield a similar distance but with varying trajectories and thus roll (on the green).
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Lob wedge
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Use
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Lob wedges can be used for a variety of shots including pitch and runs and pitching over an obstacle, particularly shots requiring a very high arc, a large amount of backspin or both. Pitching over an obstacle is used in situations where a hazard of some sort, usually a water hazard, bunker or tree, is located in the line of the shot between the ball's current location and the target (often on the putting green). By utilizing a lob wedge for these short shots, the ball is carried much higher in the air than with a standard iron causing significantly less roll on the landing surface. This is most often important for short shots into difficult pin placements. Before the invention of the lob wedge, or to create a shot similar to the lob wedge, the golfer was required to perform the shot with a sand wedge or pitching wedge and to modify the shot by cutting across the ball making a glancing blow, a much riskier shot.
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Lob wedge
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History
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Traditional sets of golf irons did not always include the lob wedge. Before 1931, golfers used a single wedge, known as a "jigger", similar to the modern day pitching wedge. After 1931, additional wedges entered the golf bag starting with the sand wedge. The lob wedge was first envisioned by Dave Pelz, a former physicist for NASA, who recognized the need for higher loft wedges (at the time 60 degrees) due to the increasing complexity of the putting greens being designed at the time. This concept was taken up by the professional golfer Tom Kite, who began using the lob wedge professionally on tour spurring other professionals to follow his lead. The mainstream lob wedge was invented by Karsten Solheim, the founder of the PING line of golf products, possibly after experimenting by gluing a potato chip to a straw. Solheim was also responsible for naming the club the "L Wedge" or the "Lob Wedge", as it is currently known today.
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HTC Desire 510
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HTC Desire 510
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The HTC Desire 510 is a mid-range Android smartphone released by HTC in 2014.
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HTC Desire 510
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HTC Desire 510
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The phone received mixed reviews. Eugene Kim of PC Magazine noted that despite having a 64-bit processor, the phone "under-delivers on most other fronts". Matt Hanson of TechRadar noted the phone's 4G connectivity and low price, but also that the phone made budget compromises on its internal storage, screen and camera. Andrew Hoyle of CNET was more positive, noting that despite the phone's unimpressive specifications, its price tag was very reasonable because it offered 4G connectivity at a low price.
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Heinz Werner's orthogenetic principle
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Heinz Werner's orthogenetic principle
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Heinz Werner's orthogenetic principle is a foundation for current theories of developmental psychology and developmental psychopathology. Initially proposed in 1940, it was formulated in 1957 and states that "wherever development occurs it proceeds from a state of relative globality and lack of differentiation to a state of increasing differentiation, articulation, and hierarchic integration." It is an example of an organismic theory based on the intrinsic activity of living systems and is parallel to Piaget's genetic epistemology both emphasizing a holistic view of development.
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Heinz Werner's orthogenetic principle
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Heinz Werner's orthogenetic principle
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In contrast to stage theories of development such as Sigmund Freud's description of psychosexual development that posited a particular sequence of behavior, Werner's principle provides a direction for development that can be applied to any behavioral domain. He asserted that the principle provided a single framework for understanding change in child psychology, psychopathology, ethnopsychology, and individual differences. He believed that although the content of these areas may be different, there was a formal similarity of the sequences within each domain moving from the global to the hierarchically integrated.
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User interface markup language
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User interface markup language
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A user interface markup language is a markup language that renders and describes graphical user interfaces and controls. Many of these markup languages are dialects of XML and are dependent upon a pre-existing scripting language engine, usually a JavaScript engine, for rendering of controls and extra scriptability.
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User interface markup language
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User interface markup language
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The concept of the user interface markup languages is primarily based upon the desire to prevent the "re-invention of the wheel" in the design, development and function of a user interface; such re-invention comes in the form of coding a script for the entire user interface. The typical user interface markup language solidifies often re-used program or script code in the form of markup, making it easier to focus upon design of a user interface in an understandable dialect as opposed to focus on function.
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User interface markup language
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User interface markup language
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User interface markup languages, like most markup and programming languages, rely upon sub-application runtimes to interpret and render the markup code as program code that can be processed and put out in the desired form. In XML-based user interface markup languages, the markup is usually interpreted and represented as a tree of nodes that may be manipulated at runtime by the application's code or dynamically loaded user script.
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User interface markup language
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User interface markup languages
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XFD XFD, which stands for XML Form Definition is the user interface markup language behind STARLIMS product ([1]), developed by Abbott Informatics. STARLIMS product has an entire ecosystem of runtime and design time tools to run and create visual forms using XFD language. STARLIMS v10 is powered by an XFD runtime developed using Microsoft .NET Framework and hosted in Internet Explorer browser. STARLIMS v11 introduces an additional XFD engine based on a server-side transformation engine that transforms the XFD into HTML5 compatible data designed to run on any HTML5 compliant browser. XFD is programmable in JavaScript based language.
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User interface markup language
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User interface markup languages
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QML QML is a cross-platform markup language for creating hardware-accelerated OpenGL-powered user interfaces for devices ranging from mobile to desktop. QML interfaces are manipulated using the JavaScript language. QML is part of the Qt software framework.
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User interface markup language
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User interface markup languages
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MXML MXML is the XML-based user interface markup language introduced by Macromedia in March 2004. It is now part of the Open Source (http://opensource.adobe.com) Adobe Flex SDK version 4. MXML files compile into Flash SWF via the Flex SDK, and are rendered either on the internet browser, via Adobe Flash plug-in, or as stand-alone cross-platform applications, via the Open Source Adobe AIR SDK.
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User interface markup language
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User interface markup languages
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UIML OASIS UIML is an XML-based standard user interface markup languages. It is an open standard where implementation is not restricted to a single vendor.
XUL The primary interface language of Mozilla Foundation products is XUL. XUL documents are rendered by the Gecko engine, which also renders XHTML and SVG documents. It cooperates with many existing standards and technologies, including CSS, JavaScript, DTD and RDF.
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User interface markup language
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User interface markup languages
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UsiXML UsiXML (which stands for User Interface Extensible Markup Language) is an XML-compliant markup language that describes the UI for multiple contexts of use such as Character User Interfaces (CUIs), Graphical User Interfaces (GUIs), Auditory User Interfaces, and Multimodal User Interfaces. In other words, interactive applications with different types of interaction techniques, modalities of use, and computing platforms can be described in a way that preserves the design independently from peculiar characteristics of physical computing platform.
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User interface markup language
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User interface markup languages
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WTKX WTKX is an XML-based markup language used for building Apache Pivot applications. Though it is most commonly used for defining the structure of an application's user interface, it can be used to declaratively construct any type of Java object hierarchy.
XAL eXtensible Application Language is the Markup language of Nexaweb's Enterprise Web 2.0 Suite. Developers can use this language to define applications that will run as a Java Client or an Ajax Client.
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User interface markup language
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User interface markup languages
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SVG Scalable Vector Graphics is a markup language for graphics proposed by the W3C that can support rich graphics for web and mobile applications. While SVG is not a user interface language, it includes support for vector/raster graphics, animation, interaction with the DOM and CSS, embedded media, events and scriptability. When these features are used in combination, rich user interfaces are possible.
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User interface markup language
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User interface markup languages
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SVG can also be superimposed upon another XML-compatible user interface markup language, such as XUL and XForms, as the graphics-rich portion of a user interface.
TUIX TUIX is an XML based markup language for defining user interfaces in Tribiq CMS. Developers can define both the appearance of the interfaces and their interactions. The TUIX files from different Plugins are merged before rendering facilitating easy modification of existing interfaces and addition of new functionality.
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User interface markup language
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User interface markup languages
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XAML XAML is a markup system that underlies user interface components of Microsoft's .NET Framework 3.0 and above. Its scope is more ambitious than that of most user interface markup languages, since program logic and styles are also embedded in the XAML document. Functionally, it can be seen as a combination of XUL, SVG, CSS, and JavaScript into a single XML schema.
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User interface markup language
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User interface markup languages
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Some people are critical of this design, as many standards (such as those already listed) exist for doing these things. However, it is expected to be developed with a visual tool where developers do not even need to understand the underlying markups.
I3ML I3ML is a proprietary thin client Application Delivery mechanism developed by CoKinetic Systems Corp, with client support provided by a browser plugin that will render windows-like applications over an HTTP infrastructure with minimal bandwidth needs.
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User interface markup language
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User interface markup languages
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OpenLaszlo (LZX) OpenLaszlo is a runtime environment that comprises a runtime environment and an interface definition language (Laszlo XML - LZX). LZX is a declarative user interface language which defines the widgets, application layout and scripting elements (using JavaScript) to create your application. LZX is runtime agnostic with the currently supported runtime being within Macromedia/Adobe Flash. An experimental runtime called Laszlo "Legals" that will allow OpenLaszlo (LZX) applications run in multiple runtime environments, such as DHTML/AJAX.
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User interface markup language
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User interface markup languages
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HMVCUL Hierarchical Model View Controller User Interface Language (HMVCUL) is an XML markup user interface language which supports the creation and chaining of atomic MVC triad components used in constructing HMVC GUI applications. The associated runtime provides methods which enable configuration of properties, data binding and events of each of the MVC triad elements (widget, controller, model). The runtime accomplishes this by mapping XML elements defined in an HMVCUL file to objects inside the framework, attributes to properties or to events. Chaining is accomplished by following the tree structure described inside the HMVCUL file.
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User interface markup language
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User interface markup languages
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WasabiXML WasabiXML is an XML markup language that is used to define the graphical interface in Wasabi powered applications. It is most commonly used with Winamp for making Winamp skins. WasabiXML had been developed by Nullsoft for Winamp, but it is also usable with other applications with the Wasabi SDK.
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User interface markup language
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User interface markup languages
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The root element in WasabiXML is <WasabiXML> (for Winamp skins, it is also <WinampAbstractionLayer>). The <skininfo> element shows the information for a skin. The graphical interface is held by the <container> element and the basic viewable GUI element is <layout>. Following is an example for a simple GUI with a button element: WasabiXML supports many GUI elements including: <button> <text> <vis> <eqvis> <layer> <animatedlayer> <groupdef> used in conjunction with <group><groupdef> allows the developer to define a group of GUI objects which can be re-used anywhere in the skin. Wasabi also supports XUI's which are nothing but <groups> powered by a MAKI script allowing developers to create GUI components (widgets) of their own adding to modularity.
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User interface markup language
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User interface markup languages
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WasabiXML has an XML namespace 'Wasabi::' which defines common GUI's without having the need to declare their image paths.
MARIA MARIA is a universal, declarative, multiple abstraction level, XML-based language for modelling interactive applications in ubiquitous environments.
FXML FXML is a XML-based language for defining the user interface of JavaFX applications.
Other Other markup languages incorporated into existing frameworks are: VTML for Macromedia HomeSiteApple's Interface Builder .xib format Some of these are compiled into binary forms.
In avionics, the ARINC 661 standard prescribes a binary format to define user interfaces in glass cockpits.
Borland VCL forms (.dfm and .lfm) are text files describing the windows of Delphi and Lazarus applications. They are compiled into the final executable in binary format, and use RTTI to function.
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Holt-Dern process
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Holt-Dern process
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The Holt-Dern process is a method by which silver and gold can be extracted from low-grade ores.The method was applied in mining at Park City, Utah and in the Tintic Mining District at the Tintic Smelter Site. It was named for George Dern and T.P. Holt.
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HIST2H3C
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HIST2H3C
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Histone H3.2 is a protein that in humans is encoded by the HIST2H3C gene.
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HIST2H3C
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Function
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Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. This structure consists of approximately 146 bp of DNA wrapped around a nucleosome, an octamer composed of pairs of each of the four core histones (H2A, H2B, H3, and H4). The chromatin fiber is further compacted through the interaction of a linker histone, H1, with the DNA between the nucleosomes to form higher order chromatin structures. This gene is intronless and encodes a member of the histone H3 family. Transcripts from this gene lack polyA tails; instead, they contain a palindromic termination element. This gene is found in a histone cluster on chromosome 1. This gene is one of four histone genes in the cluster that are duplicated; this record represents the telomeric copy.
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HIST2H3C
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Interactions
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HIST2H3C has been shown to interact with NCOA6.
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Bromargyrite
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Bromargyrite
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Bromyrite or bromargyrite is a natural mineral form of silver bromide found mainly in Mexico and Chile. Hardness is 1.5 to 2. Related are chlorargyrite and iodyrite.
It was first described in 1859 for an occurrence in Plateros, Zacatecas, Mexico where it occurred in a silver deposit as an oxidation product of primary ore minerals. It occurs in arid environments along with native silver, iodargyrite and smithsonite along with iron and manganese oxide minerals.
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Functional electrical stimulation
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Functional electrical stimulation
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Functional electrical stimulation (FES) is a technique that uses low-energy electrical pulses to artificially generate body movements in individuals who have been paralyzed due to injury to the central nervous system. More specifically, FES can be used to generate muscle contraction in otherwise paralyzed limbs to produce functions such as grasping, walking, bladder voiding and standing. This technology was originally used to develop neuroprostheses that were implemented to permanently substitute impaired functions in individuals with spinal cord injury (SCI), head injury, stroke and other neurological disorders. In other words, a person would use the device each time he or she wanted to generate a desired function. FES is sometimes also referred to as neuromuscular electrical stimulation (NMES).FES technology has been used to deliver therapies to retrain voluntary motor functions such as grasping, reaching and walking. In this embodiment, FES is used as a short-term therapy, the objective of which is restoration of voluntary function and not lifelong dependence on the FES device, hence the name functional electrical stimulation therapy, FES therapy (FET or FEST). In other words, the FEST is used as a short-term intervention to help the central nervous system of the person to re-learn how to execute impaired functions, instead of making the person dependent on neuroprostheses for the rest of her or his life. Initial Phase II clinical trials conducted with FEST for reaching and grasping, and walking were carried out at KITE, the research arm of the Toronto Rehabilitation Institute.
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Functional electrical stimulation
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Principles
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Neurons are electrically active cells. In neurons, information is coded and transmitted as a series of electrical impulses called action potentials, which represent a brief change in cell electric potential of approximately 80–90 mV. Nerve signals are frequency modulated; i.e. the number of action potentials that occur in a unit of time is proportional to the intensity of the transmitted signal. Typical action potential frequency is between 4 and 12 Hz. An electrical stimulation can artificially elicit this action potential by changing the electric potential across a nerve cell membrane (this also includes the nerve axon) by inducing electrical charge in the immediate vicinity of the outer membrane of the cell.FES devices take advantage of this property to electrically activate nerve cells, which then may go on to activate muscles or other nerves. However, special care must be taken in designing safe FES devices, as electric current through tissue can lead to adverse effects such as decrease in excitability or cell death. This may be due to thermal damage, electroporation of the cell membrane, toxic products from electrochemical reactions at the electrode surface, or over-excitation of the targeted neurons or muscles. Typically FES is concerned with stimulation of neurons and nerves. In some applications, FES can be used to directly stimulate muscles, if their peripheral nerves have been severed or damaged (i.e., denervated muscles). However, the majority of the FES systems used today stimulate the nerves or the points where the junction occurs between the nerve and the muscle. The stimulated nerve bundle includes motor nerves (efferent nerves—descending nerves from the central nervous system to muscles) and sensory nerves (afferent nerves—ascending nerves from sensory organs to the central nervous system).
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Functional electrical stimulation
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Principles
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The electrical charge can stimulate both motor and sensory nerves. In some applications, the nerves are stimulated to generate localized muscle activity, i.e., the stimulation is aimed at generating direct muscle contraction. In other applications, stimulation is used to activate simple or complex reflexes. In other words, the afferent nerves are stimulated to evoke a reflex, which is typically expressed as a coordinated contraction of one or more muscles in response to the sensory nerve stimulation.
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Functional electrical stimulation
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Principles
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When a nerve is stimulated, i.e., when sufficient electrical charge is provided to a nerve cell, a localized depolarization of the cell wall occurs resulting in an action potential that propagates toward both ends of the axon. Typically, one "wave" of action potentials will propagate along the axon towards the muscle (orthodromic propagation) and concurrently, as the other "wave" of action potentials will propagate towards the cell body in the central nervous system (antidromic propagation). While the direction of propagation in case of the antidromic stimulation and the sensory nerve stimulation is the same, i.e., towards the central nervous system, their end effects are very different. The antidromic stimulus has been considered an irrelevant side effect of FES. However, in recent years a hypothesis has been presented suggesting the potential role of the antidromic stimulation in neurorehabilitation. Typically, FES is concerned with orthodromic stimulation and uses it to generate coordinated muscle contractions.
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Functional electrical stimulation
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Principles
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In the case where sensory nerves are stimulated, the reflex arcs are triggered by the stimulation on sensory nerve axons at specific peripheral sites. One example of such a reflex is the flexor withdrawal reflex. The flexor withdrawal reflex occurs naturally when a sudden, painful sensation is applied to the sole of the foot. It results in flexion of the hip, knee and ankle of the affected leg, and extension of the contralateral leg in order to get the foot away from the painful stimulus as quickly as possible. The sensory nerve stimulation can be used to generate desired motor tasks, such as evoking flexor withdrawal reflex to facilitate walking in individuals following stroke, or they can be used to alter reflexes or the function of the central nervous system. In the later case, the electrical stimulation is commonly described by the term neuromodulation.
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Functional electrical stimulation
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Principles
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Nerves can be stimulated using either surface (transcutaneous) or subcutaneous (percutaneous or implanted) electrodes. The surface electrodes are placed on the skin surface above the nerve or muscle that needs to be "activated". They are noninvasive, easy to apply, and generally inexpensive. Until recently the common belief in the FES field has been that due to the electrode-skin contact impedance, skin and tissue impedance, and current dispersion during stimulation, much higher-intensity pulses are required to stimulate nerves using surface stimulation electrodes as compared to the subcutaneous electrodes.
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Functional electrical stimulation
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Principles
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(This statement is correct for all commercially available stimulators except MyndMove stimulator (developed my Milos R. Popovic), which has implemented a new stimulation pulse that allows the stimulator to generate muscle contractions without causing discomfort during stimulation, which is a common problem with commercially available transcutaneous electrical stimulation systems, based on US Patents 8,880,178 (2014), 9,440,077 (2016), and 9,592,380 (2016) and related foreign patents.)A major limitation of the transcutaneous electrical stimulation is that some nerves, for example those innervating the hip flexors, are too profound to be stimulated using surface electrodes. This limitation can be partly addressed by using arrays of electrodes, which can use several electrical contacts to increase selectivity.Subcutaneous electrodes can be divided into percutaneous and implanted electrodes. The percutaneous electrodes consist of thin wires inserted through the skin and into muscular tissue close to the targeted nerve. These electrodes typically remain in place for a short period of time and are only considered for short-term FES interventions. However, it is worth mentioning that some groups, such as Cleveland FES Center, have been able to safely use percutaneous electrodes with individual patients for months and years at a time. One of the drawbacks of using the percutaneous electrodes is that they are prone to infection and special care has to be taken to prevent such events.
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Functional electrical stimulation
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Principles
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The other class of subcutaneous electrodes is implanted electrodes. These are permanently implanted in the consumer's body and remain in the body for the remainder of the consumer's life. Compared to surface stimulation electrodes, implanted and percutaneous electrodes potentially have higher stimulation selectivity, which is a desired characteristics of FES systems. To achieve higher selectivity while applying lower stimulation amplitudes, it is recommended that both cathode and anode are in the vicinity of the nerve that is stimulated. The drawbacks of the implanted electrodes are they require an invasive surgical procedure to install, and, as is the case with every surgical intervention, there exists a possibility of infection following implantation.
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Functional electrical stimulation
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Principles
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Typical stimulation protocols used in clinical FES involves trains of electric pulses. Biphasic, charged balanced pulses are employed as they improve the safety of electrical stimulation and minimize some of the adverse effects. Pulse duration, pulse amplitude and pulse frequency are the key parameters that are regulated by the FES devices. The FES devices can be current or voltage regulated. Current regulated FES systems always deliver the same charge to the tissue regardless of the skin/tissue resistance. Because of that, the current regulated FES systems do not require frequent adjustments of the stimulation intensity. The voltage regulated devices may require more frequent adjustments of the stimulation intensity as the charge that they deliver changes as the skin/tissue resistance changes. The properties of the stimulation pulse trains and how many channels are used during stimulation define how complex and sophisticated FES-induced function is. The system can be as simple such as FES systems for muscle strengthening or they can be complex such as FES systems used to deliver simultaneous reaching and grasping, or bipedal locomotion.Note: This paragraph was developed in part using material from the following reference. For more information on FES please consult that and other references provided in the paragraph.
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Functional electrical stimulation
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History
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Electrical stimulation had been utilized as far back as ancient Egypt, when it was believed that placing torpedo fish in a pool of water with a human was therapeutic. FES - which involves stimulating the target organ during a functional movement (e.g., walking, reaching for an item) - was initially referred to as functional electrotherapy by Liberson. It was not until 1967 that the term functional electrical stimulation was coined by Moe and Post, and used in a patent entitled, "Electrical stimulation of muscle deprived of nervous control with a view of providing muscular contraction and producing a functionally useful moment". Offner's patent described a system used to treat foot drop.
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Functional electrical stimulation
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History
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The first commercially available FES devices treated foot drop by stimulating the peroneal nerve during gait. In this case, a switch, located in the heel end of a user's shoe, would activate a stimulator worn by the user.
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Functional electrical stimulation
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Common applications
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Spinal cord injury Injuries to the spinal cord interfere with electrical signals between the brain and the muscles, resulting in paralysis below the level of injury. Restoration of limb function as well as regulation of organ function are the main application of FES, although FES is also used for treatment of pain, pressure, sore prevention, etc. Some examples of FES applications involve the use of neuroprostheses that allow the people with paraplegia to walk, stand, restore hand grasp function in people with quadriplegia, or restore bowel and bladder function. High intensity FES of the quadriceps muscles allows patients with complete lower motor neuron lesion to increase their muscle mass, muscle fiber diameter, improve ultrastructural organization of contractile material, increase of force output during electrical stimulation and perform FES assisted stand-up exercises.
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Functional electrical stimulation
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Common applications
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Walking in spinal cord injury Kralj and his colleagues described a technique for paraplegic gait using surface stimulation, which remains the most popular method in use today. Electrodes are placed over the quadriceps muscles and peroneal nerves bilaterally. The user controls the neuroprosthesis with two pushbuttons attached to the left and right handles of a walking frame, or on canes or crutches. When the neuroprosthesis is turned on, both quadriceps muscles are stimulated to provide a standing posture.Kralj's approach was extended by Graupe et al. into a digital FES system that employs the power of digital signal processing to result in the Parastep FES system, based on US Patents 5,014,705 (1991), 5,016,636 (1991), 5,070,873 (1991), 5,081,989 (1992), 5,092,329 (1992) and related foreign patents. The Parastep system became the first FES system for standing and walking to receive the US FDA approval (FDA, PMA P900038, 1994) and become commercially available.
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Functional electrical stimulation
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Common applications
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The Parastep's digital design allows a considerable reduction in rate of patient-fatigue by drastically reducing of stimulation pulse-width (100–140 microseconds) and pulse-rate (12–24 per sec.), to result, in walking times of 20–60 minutes and average walking distances of 450 meters per walk, for adequately trained thoracic-level complete paraplegics patients who complete training that includes daily treadmill sessions, with some patients exceeding one mile per walk. Also, Parestep-based walking was reported to result in several medical and psychological benefits, including restoration of near-normal blood flow to lower extremities and holding of bone density decline.Walking performance with the Parastep system greatly depends on rigorous upper body conditioning-training and on a completing 3–5 months of a daily one–two-hour training program which includes 30 of more minutes of treadmill training.An alternative approach to the above techniques is the FES system for walking developed using the Compex Motion neuroprosthesis, by Popovic et al. . Compex Motion neuroprosthesis for walking is an eight to sixteen channel surface FES system used to restore voluntary walking in stroke and spinal cord injury individuals. This system does not apply peroneal nerve stimulation to enable locomotion. Instead, it activates all relevant lower limb muscles in a sequence similar to the one that brain uses to enable locomotion. The hybrid assistive systems (HAS) and the RGO walking neuroprostheses are devices that also apply active and passive braces, respectively. The braces were introduced to provide additional stability during standing and walking. A major limitation of neuroprostheses for walking that are based on surface stimulation is that the hip flexors cannot be stimulated directly. Therefore, hip flexion during walking must come from voluntary effort, which is often absent in paraplegia, or from the flexor withdrawal reflex. Implanted systems have the advantage of being able to stimulate the hip flexors, and therefore, to provide better muscle selectivity and potentially better gait patterns. Hybrid systems with exoskeleton have been also proposed to solve this problem. These technologies have been found to be successful and promising, but at the present time these FES systems are mostly used for exercise purposes and seldom as an alternative to wheelchair mobility.
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Functional electrical stimulation
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Common applications
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Stroke and upper limb recovery In the acute stage of stroke recovery, the use of cyclic electrical stimulation has been seen to increase the isometric strength of wrist extensors. In order to increase strength of wrist extensors, there must be a degree of motor function at the wrist spared following the stroke and have significant hemiplegia. Patients who will elicit benefits of cyclic electrical stimulation of the wrist extensors must be highly motivated to follow through with treatment. After 8 weeks of electrical stimulation, an increase in grip strength can be apparent. Many scales, which assess the level of disability of the upper extremities following a stroke, use grip strength as a common item. Therefore, increasing strength of wrist extensors will decrease the level of upper extremity disability.
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Functional electrical stimulation
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Common applications
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Patients with hemiplegia following a stroke commonly experience shoulder pain and subluxation; both of which will interfere with the rehabilitation process. Functional electrical stimulation has been found to be effective for the management of pain and reduction of shoulder subluxation, as well as accelerating the degree and rate of motor recovery. Furthermore, the benefits of FES are maintained over time; research has demonstrated that the benefits are maintained for at least 24 months.
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Functional electrical stimulation
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Common applications
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Drop foot Drop foot is a common symptom in hemiplegia, characterized by a lack of dorsiflexion during the swing phase of gait, resulting in short, shuffling strides. It has been shown that FES can be used to effectively compensate for the drop foot during the swing phase of the gait. At the moment just before the heel off phase of gait occurs, the stimulator delivers a stimulus to the common peroneal nerve, which results in contraction of the muscles responsible for dorsiflexion. There are currently a number of drop foot stimulators that use surface and implanted FES technologies. Drop foot stimulators have been used successfully with various patient populations, such as stroke, spinal cord injury and multiple sclerosis.
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Functional electrical stimulation
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Common applications
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The term "orthotic effect" can be used to describe the immediate improvement in function observed when the individual switches on their FES device compared to unassisted walking. This improvement disappears as soon as the person switches off their FES device. In contrast, a "training" or "therapeutic effect" is used to describe a long term improvement or restoration of function following a period of using the device which is still present even when the device is switched off. A further complication to measuring an orthotic effect and any long term training or therapeutic effects is the presence of a so-called "temporary carry over effect". Liberson et al., 1961 was the first to observe that some stroke patients appeared to benefit from a temporary improvement in function and were able to dorsiflex their foot for up to an hour after the electrical stimulation had been turned off. It has been hypothesised that this temporary improvement in function may be linked to a long term training or therapeutic effect.
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Functional electrical stimulation
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Common applications
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Stroke Hemiparetic stroke patients, who are impacted by the denervation, muscular atrophy, and spasticity, typically experience an abnormal gait pattern due to muscular weakness and the incapacity to voluntary contract certain ankle and hip muscles at the appropriate walking phase. Liberson et al., (1961) were the first to pioneer FES in stroke patients. More recently, there have been a number of studies that have been conducted in this area. A systematic review conducted in 2012 on the use of FES in chronic stroke included seven randomized controlled trials with a total of 231 participants. The review found a small treatment effect for using FES for the 6-minute walking test.
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Functional electrical stimulation
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Common applications
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Multiple sclerosis FES has also been found to be useful for treating foot drop in people with multiple sclerosis. The first use was reported in 1977 by Carnstam et al., who found that it was possible to generate strength increases through using peroneal stimulation. A more recent study examined the use of FES compared to an exercise group and found that although there was an orthotic effect for the FES group, no training effect in walking speed was found. Further qualitative analysis including all participants from the same study found improvements in activities of daily living and a reduced number of falls for those using FES compared with exercise. A further small scale (n=32) longitudinal observational study has found evidence for a significant training effect through using FES.
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Functional electrical stimulation
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Common applications
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With NMES treatment there were measurable gains in ambulatory function.However, a further large observational study (n=187) was supportive of previous findings and found a significant improvement in orthotic effect for walking speed.
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Functional electrical stimulation
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Common applications
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Cerebral palsy FES has been found to be useful for treating the symptoms of cerebral palsy. A recent randomised controlled trial (n=32) found significant orthotic and training effects for children with unilateral spastic cerebral palsy. Improvements were found in gastrocnemius spasticity, community mobility and balance skills. A recent comprehensive literature review of the area of using electrical stimulation and FES to treat children with disabilities mostly included studies on children with cerebral palsy. The reviewers summarised the evidence as the treatment having the potential to improve a number of different areas including muscle mass and strength, spasticity, passive range of motion, upper extremity function, walking speed, positioning of the foot and ankle kinematics. The review further concludes that adverse events were rare and the technology is safe and well tolerated by this population. The applications of FES for children with cerebral palsy are similar to those for adults. Some common applications of FES devices include stimulation of muscles whilst mobilizing to strengthen muscle activity, to reduce muscle spasticity, to facilitate initiation of muscle activity, or to provide a memory of movement.
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Functional electrical stimulation
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Common applications
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National Institute for Health and Care Excellence Guidelines (NICE) (UK) NICE have issued full guidelines on the treatment of drop foot of central neurological origin (IPG278). NICE have stated that "current evidence on the safety and efficacy (in terms of improving gait) of functional electrical stimulation (FES) for drop foot of central neurological origin appears adequate to support the use of this procedure provided that normal arrangements are in place for clinical governance, consent and audit".
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Functional electrical stimulation
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In popular culture
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Mark Coggins' novel No Hard Feelings (2015) features a female protagonist with a spinal cord injury who regains mobility via advanced FES technology developed by a fictional biomedical startup.
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Gestonorone acetate
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Gestonorone acetate
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Gestonorone acetate, or gestronol acetate, also known as norhydroxyprogesterone acetate, is a progestin of the 19-norprogesterone and 17α-hydroxyprogesterone groups which was developed in the early 1960s but was never marketed. It is the C17α acetate ester of gestronol (17α-hydroxy-19-norprogesterone).
Gestonorone acetate has been found to consistently inhibit ovulation at an oral dosage of 10 mg/day in combination with 50 μg/day oral ethinylestradiol. Weak or no endometrial effects were observed at an oral dosage of 100 mg/day, basal vacuoles appeared at 130 to 140 mg/day, and full endometrial secretory transformation occurred at 220 mg/day.
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