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Wannacry
The WannaCry ransomware attack was a worldwide cyberattack in May 2017 by the WannaCry ransomware cryptoworm, which targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the Bitcoin cryptocurrency. It propagated through EternalBlue, an exploit developed by the United States National Security Agency (NSA) for older Windows systems. EternalBlue was stolen and leaked by a group called The Shadow Brokers a month prior to the attack. While Microsoft had released patches previously to close the exploit, much of WannaCry's spread was from organizations that had not applied these, or were using older Windows systems that were past their end-of-life. These patches were imperative to organizations' cyber security but many were not implemented due to ignorance of their importance. Some have claimed a need for 24/7 operation, aversion to risking having formerly working applications breaking because of patch changes, lack of personnel or time to install them, or other reasons. The attack began at 07:44 UTC on 12 May 2017 and was halted a few hours later at 15:03 UTC by the registration of a kill switch discovered by Marcus Hutchins. The kill switch prevented already infected computers from being encrypted or further spreading WannaCry. The attack was estimated to have affected more than 200,000 computers across 150 countries, with total damages ranging from hundreds of millions to billions of United States dollar . Security experts believed from preliminary evaluation of the worm that the attack originated from North Korea or agencies working for the country. In December 2017, the United States and United Kingdom formally asserted that North Korea was behind the attack. A new variant of WannaCry forced Taiwan Semiconductor Manufacturing Company (TSMC) to temporarily shut down several of its chip-fabrication factories in August 2018. The virus spread to 10,000 machines in TSMC's most advanced facilities.
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  • 23 Oct 2022
Topic Review
Prisoners of War in Islam
The rules and regulations concerning prisoners of war in Islam are covered in manuals of Islamic jurisprudence, based upon Islamic teachings, in both the Qur'an and hadith. The historical legal principles governing the treatment of prisoners of war, in shar'iah, Islamic law, (in the traditional madhabs schools of Islamic jurisprudence), was then a significant improvement over the pre-existing norms of society during Muhammad's time (see Early reforms under Islam). Men, women, and children may all be taken as prisoners of war under traditional interpretations of Islamic law. Generally, a prisoner of war could be, at the discretion of the military leader, freed, ransomed, exchanged for Muslim prisoners, or kept in bondage. In earlier times, the ransom sometimes took an educational dimension, where a literate prisoner of war could secure his or her freedom by teaching ten Muslims to read and write. Some Muslim scholars hold that a prisoner may not be ransomed for gold or silver, but may be exchanged for Muslim prisoners.
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  • 23 Oct 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.
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  • 23 Oct 2022
Topic Review
Muscle
Muscle is a soft tissue found in most animals, and is one of the four basic animal tissues, along with nervous tissue, epithelium, and connective tissue. Muscle cells contain protein filaments called myofilaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis. Muscle tissue is derived from the embryonic mesodermal germ layer in a process known as myogenesis. There are three types of muscle, of which skeletal and cardiac muscle are striated and smooth muscle is not. Muscle action can be classified as being either voluntary or involuntary. Cardiac and smooth muscles contract without conscious thought and are termed involuntary, whereas the skeletal muscles contract upon command. Skeletal muscles in turn can be divided into fast and slow twitch fibers. Muscles are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast twitch fibers. These chemical reactions produce adenosine triphosphate (ATP) molecules that are used to power the movement of the myosin heads. The term muscle is derived from the Latin musculus meaning "little mouse" perhaps because of the shape of certain skeletal muscles or because contracting muscles look like mice moving under the skin.
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  • 22 Oct 2022
Topic Review
Ionized Water
A water ionizer (also known as an alkaline ionizer) is a home appliance which claims to raise the pH of drinking water by using electrolysis to separate the incoming water stream into acidic and alkaline components. The alkaline stream of the treated water is called alkaline water. Proponents claim that consumption of alkaline water results in a variety of health benefits, making it similar to the alternative health practice of alkaline diets. Such claims violate basic principles of chemistry and physiology. There is no medical evidence for any health benefits of alkaline water. Extensive scientific evidence has completely debunked these claims. The machines originally became popular in Japan and other East Asian countries before becoming available in the United States and Europe.
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  • 22 Oct 2022
Topic Review
Trique Language
The Triqui (/ˈtriːki/), or Trique, languages are Oto-Manguean languages of Mexico spoken by the Trique people of the state of Oaxaca and the state of Baja California (due to recent population movements). They belong to the Mixtecan branch together with the Mixtec languages and Cuicatec.
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  • 21 Oct 2022
Topic Review
In-Space Propulsion Technologies
Proposed in-space propulsion technologies describe the propulsion technologies that could meet future space science and exploration needs. These propulsion technologies are intended to provide effective exploration of our Solar System and will permit mission designers to plan missions to "fly anytime, anywhere, and complete a host of science objectives at the destinations" and with greater reliability and safety. With a wide range of possible missions and candidate propulsion technologies, the question of which technologies are "best" for future missions is a difficult one. A portfolio of propulsion technologies should be developed to provide optimum solutions for a diverse set of missions and destinations. In-space propulsion begins where the upper stage of the launch vehicle leaves off; performing the functions of primary propulsion, reaction control, station keeping, precision pointing, and orbital maneuvering. The main engines used in space provide the primary propulsive force for orbit transfer, planetary trajectories and extra planetary landing and ascent. The reaction control and orbital maneuvering systems provide the propulsive force for orbit maintenance, position control, station keeping, and spacecraft attitude control.
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  • 21 Oct 2022
Topic Review
Biblical Apocrypha
The biblical apocrypha (from the Greek ἀπόκρυφος, apókruphos, meaning "hidden") denotes the collection of apocryphal ancient books found in some editions of Christian Bibles in a separate section between the Old and New Testaments or as an appendix after the New Testament. Some Christian Churches include some or all of the same texts within the body of their version of the Old Testament. Although the term apocrypha had been in use since the 5th century, it was in Luther's Bible of 1534 that the Apocrypha was first published as a separate intertestamental section. To this date, the Apocrypha is "included in the lectionaries of Anglican and Lutheran Churches." Moreover, the Revised Common Lectionary, in use by most mainline Protestants including Methodists and Moravians, lists readings from the Apocrypha in the liturgical kalendar, although alternate Old Testament scripture lessons are provided. The preface to the Apocrypha in the Geneva Bible explained that while these books "were not received by a common consent to be read and expounded publicly in the Church," and did not serve "to prove any point of Christian religion save in so much as they had the consent of the other scriptures called canonical to confirm the same," nonetheless, "as books proceeding from godly men they were received to be read for the advancement and furtherance of the knowledge of history and for the instruction of godly manners." Later, during the English Civil War, the Westminster Confession of 1647 excluded the Apocrypha from the canon and made no recommendation of the Apocrypha above "other human writings", and this attitude towards the Apocrypha is represented by the decision of the British and Foreign Bible Society in the early 19th century not to print it (see below). Today, "English Bibles with the Apocrypha are becoming more popular again" and they are often printed as intertestamental books. Most of the books of the Protestant Apocrypha are called deuterocanonical by Catholics per the Council of Trent and all of them are called anagignoskomena by the Eastern Orthodox per the Synod of Jerusalem. The Anglican Communion accepts "the Apocrypha for instruction in life and manners, but not for the establishment of doctrine (Article VI in the Thirty-Nine Articles)", and many "lectionary readings in The Book of Common Prayer are taken from the Apocrypha", with these lessons being "read in the same ways as those from the Old Testament". The first Methodist liturgical book, The Sunday Service of the Methodists, employs verses from the Apocrypha, such as in the Eucharistic liturgy. The Protestant Apocrypha contains three books (3 Esdras, 4 Esdras and the Prayer of Manasseh) that are accepted by many Eastern Orthodox Churches and Oriental Orthodox Churches as canonical, but are regarded as non-canonical by the Catholic Church and are therefore not included in modern Catholic Bibles.
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  • 21 Oct 2022
Topic Review
Multispectral Image
Multispectral imaging captures image data within specific wavelength ranges across the electromagnetic spectrum. The wavelengths may be separated by filters or detected with the use of instruments that are sensitive to particular wavelengths, including light from frequencies beyond the visible light range, i.e. infrared and ultra-violet. Spectral imaging can allow extraction of additional information the human eye fails to capture with its visible receptors for red, green and blue. It was originally developed for military target identification and reconnaissance. Early space-based imaging platforms incorporated multispectral imaging technology to map details of the Earth related to coastal boundaries, vegetation, and landforms. Multispectral imaging has also found use in document and painting analysis. Multispectral imaging measures light in a small number (typically 3 to 15) of spectral bands. Hyperspectral imaging is a special case of spectral imaging where often hundreds of contiguous spectral bands are available.
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  • 21 Oct 2022
Topic Review
List of Open Formats
An open format is a file format for storing digital data, defined by a published specification usually maintained by a standards organization, and which can be used and implemented by anyone. For example, an open format can be implemented by both proprietary and free and open source software, using the typical software licenses used by each. In contrast to open formats, closed formats are considered trade secrets. Open formats are also called free file formats if they are not encumbered by any copyrights, patents, trademarks or other restrictions (for example, if they are in the public domain) so that anyone may use them at no monetary cost for any desired purpose. Open formats (in alphabetical order) include:
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  • 21 Oct 2022
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