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Topic Review
Quadruple and Quintuple Innovation Helix (Q2IH) Framework
The quadruple along with the quintuple innovation helix framework was co-developed by Elias G. Carayannis and David F.J. Campbell, with the quadruple helix being described in a 2009 article and the quintuple helix in a 2010 article. It extends and expands substantially the triple helix model of innovation economics as the framework introduces civil society and the environment as pillars and focal points of policy and practice. In particular, civil society emphasizes the role of bottom-up initiatives complementing top-down government, university and industry policies and practices, and the environment emphasizes the sustainability priorities and exigencies that need to inform and moderate top-down policies and practices as well as bottom-up initiatives. Within the quintuple helix, these represent the sine qua non of smart, sustainable and inclusive growth. The quintuple helix views the natural environments of society and the economy as drivers for knowledge production and innovation, thus defining opportunities for the knowledge society and knowledge economy. The quintuple helix can be described in terms of the models of knowledge that it extends, the five subsystems (helices) it incorporates, and the steps involved in the circulation of knowledge. How to define these new helices has been debated and some researchers see them as additional helices while some see them as different types of helix which overarch the previous helices.
  • 11.6K
  • 22 Nov 2022
Topic Review
Bearing (Navigation)
In navigation, bearing is the horizontal angle between the direction of an object and another object, or between it and that of true north.
  • 11.6K
  • 05 Dec 2022
Topic Review
Artificial Intelligence in Education (AIED)
Artificial Intelligence in Education (AIED) has 3 meanings : The first is “education for understanding AI,” which aims to develop the ability to understand and handle AI. The second is “education using AI,” which applies AI to effective teaching and learning in each subject. The third is “AI expert training,” which cultivates experts who develop AI and teachers who teach AI.
  • 11.6K
  • 27 Jul 2021
Topic Review
Partition (Number Theory)
In number theory and combinatorics, a partition of a positive integer n, also called an integer partition, is a way of writing n as a sum of positive integers. Two sums that differ only in the order of their summands are considered the same partition. (If order matters, the sum becomes a composition.) For example, 4 can be partitioned in five distinct ways: 4 3 + 1 2 + 2 2 + 1 + 1 1 + 1 + 1 + 1 The order-dependent composition 1 + 3 is the same partition as 3 + 1, and the two distinct compositions 1 + 2 + 1 and 1 + 1 + 2 represent the same partition 2 + 1 + 1. A summand in a partition is also called a part. The number of partitions of n is given by the partition function p(n). So p(4) = 5. The notation λ ⊢ n means that λ is a partition of n. Partitions can be graphically visualized with Young diagrams or Ferrers diagrams. They occur in a number of branches of mathematics and physics, including the study of symmetric polynomials and of the symmetric group and in group representation theory in general.
  • 11.6K
  • 04 Nov 2022
Topic Review
Media Ecology
Media ecology theory is the study of media, technology, and communication and how they affect human environments. The theoretical concepts were proposed by Marshall McLuhan in 1964, while the term media ecology was first formally introduced by Neil Postman in 1968. Ecology in this context refers to the environment in which the medium is used – what they are and how they affect society. Neil Postman states, "if in biology a 'medium' is something in which a bacterial culture grows (as in a Petri dish), in media ecology, the medium is 'a technology within which a [human] culture grows.'" In other words, "Media ecology looks into the matter of how media of communication affect human perception, understanding, feeling, and value; and how our interaction with media facilitates or impedes our chances of survival. The word ecology implies the study of environments: their structure, content, and impact on people. An environment is, after all, a complex message system which imposes on human beings certain ways of thinking, feeling, and behaving." Media ecology argues that media act as extensions of the human senses in each era, and communication technology is the primary cause of social change. McLuhan is famous for coining the phrase, "the medium is the message", which is an often-debated phrase believed to mean that the medium chosen to relay a message is just as important (if not more so) than the message itself. McLuhan proposed that media influence the progression of society, and that significant periods of time and growth can be categorized by the rise of a specific technology during that period. Additionally, scholars have compared media broadly to a system of infrastructure that connect the nature and culture of a society with media ecology being the study of "traffic" between the two.
  • 11.5K
  • 23 Oct 2022
Topic Review
Peculiarities of Tumor Cell Metabolism for Cancer Treatment
In tumor cells, ketolysis “via” succinyl-CoA: 3-oxoacid-CoAtransferase (SCOT) and acetyl-CoA acetyltransferase 1 (ACAT1) is a major source of mitochondrial acetyl-CoA. Active ACAT1 tetramers stabilize by tyrosine phosphorylation, which facilitates the SCOT reaction and ketolysis. Tyrosine phosphorylation of pyruvate kinase PK M2 has the opposite effect, stabilizing inactive dimers, while pyruvate dehydrogenase (PDH), which is already inhibited by phosphorylation, is acetylated by ACAT1 and is doubly locked. This closes the glycolytic supply of acetyl-CoA. In addition, since tumor cells must synthesize fatty acids to create new membranes, they automatically turn off the degradation of fatty acids into acetyl-CoA (“via” the malonyl-CoA brake for the fatty acid carnityl transporter). Thus, inhibiting SCOT the specific ketolytic enzyme and ACAT1 should hold back tumor progression. However, tumor cells are still able to take up external acetate and convert it into acetyl-CoA in their cytosol “via” an acetyl-CoA synthetase, which feeds the lipogenic pathway; additionally, inhibiting this enzyme would make it difficult for tumor cells to form new lipid membrane and survive.
  • 11.5K
  • 21 Feb 2023
Topic Review
Emerging Technologies
According to G. Veletsianos, from a general point of view, an emerging technology is “a new tool with promising potential”. However, an emerging technology is generally defined according to the field in which it is analyzed. B.R. Martin describes an emerging technology as a technology the use of which will benefit many sectors of the economy and/or society. Other important characteristics of emerging technology, according to D. Rotolo, D. Hicks and B. R. Martin, include radical novelty, relatively fast growth, coherence, and prominent impact. Which refers to the crucial following contexts: aspect of future time, anticipation, uncertainty and Industry 4.0. the following definition of an emerging technology has been created by the author – „Emerging technology in Industry 4.0 is a technology the development of which, from today’s point of view, is uncertain and not obvious, but through complex anticipatory research, it is possible to identify its potential radical impact in selected areas, e.g., social, technological, economic, scientific.”
  • 11.5K
  • 10 Dec 2021
Topic Review
Eyelash Curler
An eyelash curler is a hand-operated mechanical device for curling eyelashes for cosmetic purposes. Usually only the upper eyelashes are curled.
  • 11.5K
  • 25 Nov 2022
Topic Review
Humid Continental Climate
A humid continental climate is a climatic region defined by Russo-German climatologist Wladimir Köppen in 1900, typified by four distinct seasons and large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold in the northern areas) winters. Precipitation is usually distributed throughout the year. The definition of this climate regarding temperature is as follows: the mean temperature of the coldest month must be below −3 °C (26.6 °F) and there must be at least four months whose mean temperatures are at or above 10 °C (50 °F). In addition, the location in question must not be semi-arid or arid. The Dfb, Dwb and Dsb subtypes are also known as hemiboreal. Humid continental climates are generally found roughly between latitudes 40° N and 60° N, within the central and northeastern portions of North America, Europe, and Asia. They are much less commonly found in the Southern Hemisphere due to the larger ocean area at that latitude and the consequent greater maritime moderation. In the Northern Hemisphere some of the humid continental climates, typically in Hokkaido, Northern Honshu, Sakhalin island, Scandinavia, Nova Scotia, and Newfoundland are heavily maritime-influenced, with relatively cool summers and winters being just below the freezing mark. More extreme humid continental climates found in northeast China , southern Siberia, the Canadian Prairies, and the Great Lakes region of the American Midwest and Central Canada combine hotter summer maxima and colder winters than the marine-based variety.
  • 11.5K
  • 29 Sep 2022
Topic Review
Types of Electrochemical Sensors
The world of sensors is diverse and is advancing at a rapid pace due to the fact of its high demand and constant technological improvements. Electrochemical sensors provide a low-cost and convenient solution for the detection of variable analytes and are widely utilized in agriculture, food, and oil industries as well as in environmental and biomedical applications. The popularity of electrochemical sensing stems from two main advantages: the variability of the reporting signals, such as the voltage, current, overall power output, or electrochemical impedance, and the low theoretical detection limits that originate from the differences in the Faradaic and nonFaradaic currents.
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  • 09 Nov 2022
Topic Review
The Hook
The Hook, or The Hookman, is an urban legend about a killer with a pirate-like hook for a hand attacking a couple in a parked car. The story is thought to date from at least the mid-1950s, and gained significant attention when it was reprinted in the advice column Dear Abby in 1960. It has since become a morality archetype in popular culture, and has been referenced in various horror films.
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  • 03 Mar 2023
Topic Review
Mechanisms of anticoagulant drugs
Anticoagulant drugs have been used to prevent and treat thrombosis. However, they are associated with risk of hemorrhage. Therefore, prior to their clinical use, it is important to assess the risk of bleeding and thrombosis. In case of older anticoagulant drugs like heparin and warfarin, dose adjustment is required owing to narrow therapeutic ranges. The established monitoring methods for heparin and warfarin are activated partial thromboplastin time (APTT)/anti-Xa assay and prothrombin time – international normalized ratio (PT-INR), respectively. Since 2008, new generation anticoagulant drugs, called direct oral anticoagulants (DOACs), have been widely prescribed to prevent and treat several thromboembolic diseases. Although the use of DOACs without routine monitoring and frequent dose adjustment has been shown to be safe and effective, there may be clinical circumstances in specific patients when measurement of the anticoagulant effects of DOACs is required. Recently, anticoagulation therapy has received attention when treating patients with coronavirus disease 2019 (COVID-19).
  • 11.5K
  • 23 Feb 2023
Topic Review
Six-factor Model of Psychological Well-being
The Six-factor Model of Psychological Well-being is a theory developed by Carol Ryff which determines six factors which contribute to an individual's psychological well-being, contentment, and happiness. Psychological well-being consists of positive relationships with others, personal mastery, autonomy, a feeling of purpose and meaning in life, and personal growth and development. Psychological well-being is attained by achieving a state of balance affected by both challenging and rewarding life events.
  • 11.4K
  • 20 Oct 2022
Topic Review
Bryophyllum Pinnatum
Bryophyllum pinnatum, also known as the air plant, cathedral bells, life plant, miracle leaf, and Goethe plant is a succulent plant native to Madagascar , which is a popular houseplant and has become naturalized in tropical and subtropical areas. It is distinctive for the profusion of miniature plantlets that form on the margins of its phylloclades, a trait it has in common with some other members of its genus. Many people also currently call this plant Kalanchoe pinnata. It is a succulent, perennial plant, about 1 m (39 in) tall, with a fleshy cylindrical stem and a reddish color for the youngest and it flowers most of the year. The specific epithet "pinnata" is the feminine form of the Latin adjective pinnatus, meaning "winged, pinnate".
  • 11.4K
  • 30 Nov 2022
Topic Review
List of ASTM International Standards (F)
This is a list of ASTM International standards for "Materials for Specific Applications".
  • 11.4K
  • 24 Nov 2022
Topic Review
Anaphase Bridges
Anaphase bridges are DNA threads stretching between the two DNA masses as cells attempt to segregate them during anaphase. Anaphase bridges arise from unresolved DNA intertwines between sister chromatids. Sister chromatid intertwines (SCIs) naturally arise during DNA replication and represent a non-proteinaceous source of cohesion between sister chromatids. SCIs and are mainly resolved in S phase, although some do persist and must be fully removed during mitosis to allow faithful chromosome segregation and avoid the arising of DNA lesions and genome instability, a hallmark of cancer development. As complete resolution of SCIs only occurs during chromosome segregation, it is not clear whether intertwines that persist in mitosis are simply an unwanted leftover or whether they have a functional role.
  • 11.4K
  • 04 Sep 2020
Topic Review
High Dynamic Range (Display and Formats)
High Dynamic Range (HDR) is a video and image technology that improves the way light is represented. It overcomes the limits of the standard format that is named Standard Dynamic Range (SDR). HDR offers the possibility to represent substantially brighter highlights, darker shadows, more details in both sides and more colorful colors than what was previously possible. HDR do not increase display's capabilities, rather it allows to make better use of displays that have high brightness, contrast and colors capabilities. Not all HDR displays have the same capabilities and HDR contents will thus look different depending the display used. HDR emerged first for videos in 2014. HDR10, HDR10+, Dolby Vision and HLG are common HDR formats. Some still pictures formats do also support HDR.
  • 11.4K
  • 01 Nov 2022
Topic Review
Electric Arc Furnace Slag
EAF slag is a non-metallic by-product that consists mainly of silicates and oxides formed during the process of refining the molten steel. Raw EAF slag often appears as grey or black colored lumps, depending on its ferrous oxide content. This type of slag generally has a rough surface texture, with a surface pore diameter of 0.01–10 μm.
  • 11.4K
  • 26 Oct 2020
Topic Review
Soil Bioremediation
Petroleum hydrocarbons, heavy metals and agricultural pesticides have mutagenic, carcinogenic, immunotoxic and teratogenic effects and cause drastic changes in soil physicochemical and microbiological characteristics, thereby representing a serious danger to health and environment. Therefore, soil pollution urgently requires the application of a series of physicochemical and biological techniques and treatments to minimize the extent of damage. Among them, bioremediation has been shown to be an alternative that can offer an economically viable way to restore polluted areas.
  • 11.4K
  • 27 Oct 2020
Topic Review
Plasmons
Researchers briefly review applications of surface-plasmon polariton modes, related to the design and fabrication of electro–optical circuits.
  • 11.4K
  • 14 Jan 2025
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