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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Effects of Stress on Memory
The effects of stress on memory include interference with a person's capacity to encode memory and the ability to retrieve information. During times of stress, the body reacts by secreting stress hormones into the bloodstream. Stress can cause acute and chronic changes in certain brain areas which can cause long-term damage. Over-secretion of stress hormones most frequently impairs long-term delayed recall memory, but can enhance short-term, immediate recall memory. This enhancement is particularly relative in emotional memory. In particular, the hippocampus, prefrontal cortex and the amygdala are affected. One class of stress hormone responsible for negatively affecting long-term, delayed recall memory is the glucocorticoids (GCs), the most notable of which is cortisol. Glucocorticoids facilitate and impair the actions of stress in the brain memory process. Cortisol is a known biomarker for stress. Under normal circumstances, the hippocampus regulates the production of cortisol through negative feedback because it has many receptors that are sensitive to these stress hormones. However, an excess of cortisol can impair the ability of the hippocampus to both encode and recall memories. These stress hormones are also hindering the hippocampus from receiving enough energy by diverting glucose levels to surrounding muscles. Stress affects many memory functions and cognitive functioning of the brain. There are different levels of stress and the high levels can be intrinsic or extrinsic. Intrinsic stress level is triggered by a cognitive challenge whereas extrinsic can be triggered by a condition not related to a cognitive task. Intrinsic stress can be acutely and chronically experienced by a person. The varying effects of stress on performance or stress hormones are often compared to or known as "inverted-u" which induce areas in learning, memory and plasticity. Chronic stress can affect the brain structure and cognition. Studies considered the effects of both intrinsic and extrinsic stress on memory functions, using for both of them Pavlovian conditioning and spatial learning. In regard to intrinsic memory functions, the study evaluated how stress affected memory functions that was triggered by a learning challenge. In regard to extrinsic stress, the study focused on stress that was not related to cognitive task but was elicited by other situations. The results determined that intrinsic stress was facilitated by memory consolidation process and extrinsic stress was determined to be heterogeneous in regard to memory consolidation.[clarification needed] Researchers found that high stress conditions were a good representative of the effect that extrinsic stress can cause on memory functioning.[clarification needed] It was also proven that extrinsic stress does affect spatial learning whereas acute extrinsic stress does not.[clarification needed]
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  • 27 Oct 2022
Topic Review
Wila (Lichen)
Wila (Bryoria fremontii) is a dark brown, hair-like lichen that grows hanging from trees in western North America, and northern Europe and Asia. Wila grows abundantly in some areas, and is an important traditional food for many First Nations in North America.
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  • 27 Oct 2022
Topic Review
Christian
A Christian (/ˈkrɪstʃən, -tiən/ (listen)) is a person who follows or adheres to Christianity, an Abrahamic, monotheistic religion based on the life and teachings of Jesus Christ. "Christian" derives from the Koine Greek word Christós (Χριστός), a translation of the Biblical Hebrew term mashiach (Biblical Hebrew: מָשִׁיחַ). While there are diverse interpretations of Christianity which sometimes conflict, they are united in believing that Jesus has a unique significance. The term "Christian" is also used as an adjective to describe anything associated with Christianity, or in a proverbial sense "all that is noble, and good, and Christ-like." According to a 2011 Pew Research Center survey, there were 2.2 billion Christians around the world in 2010, up from about 600 million in 1910. By 2050, the Christian population is expected to exceed 3 billion. According to a 2012 Pew Research Center survey Christianity will remain the world's largest religion in 2050, if current trends continue. Today, about 37% of all Christians live in the Americas, about 26% live in Europe, 24% live in sub-Saharan Africa, about 13% live in Asia and the Pacific, and 1% live in the Middle East and North Africa. About half of all Christians worldwide are Catholic, while more than a third are Protestant (37%). Orthodox communions comprise 12% of the world's Christians. Other Christian groups make up the remainder. Christians make up the majority of the population in 158 countries and territories. 280 million Christians live as a minority. Christians have significantly influenced and contributed to human progress in many fields including philanthropy, philosophy,:15 ethics, literature, business and economics, fine arts and architecture, music, theatre and medicine, as well as science and technology, both historically and in modern times.
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  • 27 Oct 2022
Topic Review
Red Eye
A red eye is an eye that appears red due to illness or injury. It is usually injection and prominence of the superficial blood vessels of the conjunctiva, which may be caused by disorders of these or adjacent structures. Conjunctivitis and subconjunctival hemorrhage are two of the less serious but more common causes. Management includes assessing whether emergency action (including referral) is needed, or whether treatment can be accomplished without additional resources. Slit lamp examination is invaluable in diagnosis but initial assessment can be performed using a careful history, testing vision (visual acuity), and carrying out a penlight examination.
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  • 27 Oct 2022
Topic Review
Factors of Polymer Weathering
The aging of natural and artificial polymeric materials is a natural phenomenon in metals, glass, minerals and other inorganic materials. The main environmental parameters influencing the degradation of polymeric materials is daylight combined with the effects of temperature, moisture and oxygen. These act as the main parameters of stress for outdoor weathering.
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  • 27 Oct 2022
Topic Review
Occultism in Nazism
Nazism and occultism describes a range of theories, speculation and research into the origins of Nazism and its possible relation to various occult traditions. Such ideas have been a part of popular culture since at least the early 1940s, during World War II, and gained renewed popularity starting in the 1960s. There are documentaries and books on the topic, among the most significant are The Morning of the Magicians (1960) and The Spear of Destiny (1972). Nazism and occultism has also been featured in numerous films, novels, comic books and other fictional media. Some good examples are the film Raiders of the Lost Ark (1981) and the comic book series Hellboy. Historian Nicholas Goodrick-Clarke analyzed the topic in The Occult Roots of Nazism in which he argued there were in fact links between some ideals of Ariosophy and Nazi ideology. He also analyzed the problems of the numerous popular occult historiography books written on the topic. He sought to separate empiricism and sociology from the modern mythology of Nazi occultism that exists in many books which "have represented the Nazi phenomenon as the product of arcane and demonic influence". He considered most of these to be "sensational and under-researched".
  • 3.3K
  • 27 Oct 2022
Topic Review
Asynchronous Transfer Mode
Asynchronous Transfer Mode (ATM) is a telecommunications standard defined by ANSI and ITU (formerly CCITT) for digital transmission of multiple types of traffic, including telephony (voice), data, and video signals in one network without the use of separate overlay networks. ATM was developed to meet the needs of the Broadband Integrated Services Digital Network, as defined in the late 1980s, and designed to integrate telecommunication networks. It can handle both traditional high-throughput data traffic and real-time, low-latency content such as voice and video. ATM provides functionality that uses features of circuit switching and packet switching networks. It uses asynchronous time-division multiplexing, and encodes data into small, fixed-sized network packets. In the ISO-OSI reference model data link layer (layer 2), the basic transfer units are generically called frames. In ATM these frames are of a fixed (53 octets or bytes) length and specifically called cells. This differs from approaches such as IP or Ethernet that use variable sized packets or frames. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the data exchange begins. These virtual circuits may be either permanent, i.e. dedicated connections that are usually preconfigured by the service provider, or switched, i.e. set up on a per-call basis using signaling and disconnected when the call is terminated. The ATM network reference model approximately maps to the three lowest layers of the OSI model: physical layer, data link layer, and network layer. ATM is a core protocol used in the SONET/SDH backbone of the public switched telephone network (PSTN) and in the Integrated Services Digital Network (ISDN), but has largely been superseded in favor of next-generation networks based in Internet Protocol (IP) technology, while wireless and mobile ATM never established a significant foothold.
  • 1.6K
  • 27 Oct 2022
Topic Review
Technology Forecasting
Technology forecasting attempts to predict the future characteristics of useful technological machines, procedures or techniques. Researchers create technology forecasts based on past experience and current technological developments. Like other forecasts, technology forecasting can be helpful for both public and private organizations to make smart decisions. By analyzing future opportunities and threats, the forecaster can improve decisions in order to achieve maximum benefits. Today, most countries are experiencing huge social and economic changes, which heavily rely on technology development. By analyzing these changes, government and economic institutions could make plans for future developments. However, not all of historical data can be used for technology forecasting, forecasters also need to adopt advanced technology and quantitative modeling from experts’ researches and conclusions.
  • 5.2K
  • 27 Oct 2022
Topic Review
Social Infrastructure
Social infrastructure is a general term referring to a class of internet services which allow websites or mobile devices to integrate social functionality into their application user experience. Such functionality includes social login, sharing, commenting, activity feeds, online identity storage, gamification and others. The technologies and services comprising social infrastructure are made available by a variety of sources including social network providers such as Facebook, Twitter, LinkedIn, and Google. Third-party providers like Gigya, Livefyre, Hull, Echo, BazaarVoice, Janrain, Loginradius, AddThis, and ShareThis provide services that allow applications to integrate social functionality using multiple social networks. While each provider offers a different range of social functionality to applications, all providers offer their own set of tools, plugins, SDKs and APIs to ensure their platform is accessible across as many devices as possible. Using standard programming languages (HTML, JavaScript, PHP, Java, Objective-C, etc.), applications can interface with social infrastructure from desktops, laptops, mobile phones and tablets. Indian ICT company United Telecoms Limited has implemented social infrastructure projects targeting health exchanges, tsunami warning systems, city surveillance, broadband and communication systems for rapid transportation systems.
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  • 27 Oct 2022
Topic Review
Music Without Sound
Music without sound can refer to music that falls outside the range of human hearing (typically 20 Hz–20 kHz) or to compositions, such as visual music, that are analogous to or suggestive of conventional music but in media other than sound, such as color, shape, position, motion and literature (see Discursive music below). It is commonly taken for granted that music is wont to be performed or recorded, but some sound works simply won't fit on a disc or on stage, being either extremely discreet (like Robin Minard's Silent Music) or incomplete (Varèse's Unfinished music). Additionally, silence can be regarded as the via negativa of music and has induced long lasting fascination to music composers of all kinds. A composer deals with the absence of sound as much as they deal with sounds. Therefore, this article includes several examples of apophasis in music (like Algorithmic music or Gesture Music).
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  • 27 Oct 2022
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