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Topic Review
Ali in the Quran
The majority of Islamic commentators do not believe that Ali ibn Abu Talib (Arabic: عَـلِي ابْـن أَبُـو طَـالِـب) is mentioned explicitly in the Quran. However, Shi'ite scholars and some Sunni scholars interpret many Quranic verses as referring to Ali. Shi'ite scholars also believe other Imams have been referred in the Quran. They believe Imams are referred to as "the signs of Allah, the way, the straight path, the light of Allah, the inheritors of the Book, the people of knowledge, the holders of authority and other such designations," Shi'ite sources state, Muhammad al-Baqir answers: "Allah revealed Salat to his Prophet but never said of three or four Rakats, revealed Zakat but did not mention to its details, revealed Hajj but did not count its Tawaf and the Prophet interpreted their details. Allah revealed this verse and Prophet said this verse is about Ali, Hasan, Husayn and the other Twelve Imams." Shi'ite scholars, thus, have argued that a quarter of Qur'anic verses are stating the station of imams. Such a view is rejected by Sunni scholars, who argue that some of these verses instead refer to the Quraysh or Muhammad's wives.
  • 16.9K
  • 14 Oct 2022
Topic Review
6061 Aluminium Alloy
6061 (Unified Numbering System (UNS) designation A96061) is a precipitation-hardened aluminium alloy, containing magnesium and silicon as its major alloying elements. Originally called "Alloy 61S", it was developed in 1935. It has good mechanical properties, exhibits good weldability, and is very commonly extruded (second in popularity only to 6063). It is one of the most common alloys of aluminum for general-purpose use. It is commonly available in pre-tempered grades such as 6061-O (annealed), tempered grades such as 6061-T6 (solutionized and artificially aged) and 6061-T651 (solutionized, stress-relieved stretched and artificially aged).
  • 16.9K
  • 22 Nov 2022
Topic Review
Philippine Hokkien
Philippine Hokkien (Chinese: 咱儂話; Pe̍h-ōe-jī: Lán-lâng-ōe; literally: 'our people's language'), is the variant of Hokkien as spoken by about 98.7% of the ethnic Chinese population of the Philippines. A mixed version that involves this language with Tagalog and English is Hokaglish.
  • 16.9K
  • 06 Oct 2022
Topic Review
Solar Power Plants in Iran
The world’s electricity generation has increased with renewable energy technologies such as solar (solar power plant), wind energy (wind turbines), heat energy, and even ocean waves. Iran is in the best condition to receive solar radiation due to its proximity to the equator (25.2969° N). In 2020, Iran was able to supply only 900 MW (about 480 solar power plants and 420 MW home solar power plants) of its electricity demand from solar energy, which is very low compared to the global average. Yazd, Fars, and Kerman provinces are in the top ranks of Iran, with the production of approximately 68, 58, and 47 MW using solar energy, respectively. Iran also has a large area of vacant land for the construction of solar power plants.
  • 16.8K
  • 07 Jan 2022
Topic Review
Impact of Nanotechnology
The impact of nanotechnology extends from its medical, ethical, mental, legal and environmental applications, to fields such as engineering, biology, chemistry, computing, materials science, and communications. Major benefits of nanotechnology include improved manufacturing methods, water purification systems, energy systems, physical enhancement, nanomedicine, better food production methods, nutrition and large-scale infrastructure auto-fabrication. Nanotechnology's reduced size may allow for automation of tasks which were previously inaccessible due to physical restrictions, which in turn may reduce labor, land, or maintenance requirements placed on humans. Potential risks include environmental, health, and safety issues; transitional effects such as displacement of traditional industries as the products of nanotechnology become dominant, which are of concern to privacy rights advocates. These may be particularly important if potential negative effects of nanoparticles are overlooked. Whether nanotechnology merits special government regulation is a controversial issue. Regulatory bodies such as the United States Environmental Protection Agency and the Health and Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles. The organic food sector has been the first to act with the regulated exclusion of engineered nanoparticles from certified organic produce, firstly in Australia and the UK, and more recently in Canada , as well as for all food certified to Demeter International standards
  • 16.8K
  • 18 Oct 2022
Topic Review
Smart Clothing
Smart clothing can be defined as the intelligent system that senses and reacts to the changes and stimuli of the environment and the wearer’s conditions, such as electrical, thermal and magnetic ones. Smart clothing has various functions (e.g., protection, temperature regulation, monitoring, entertainment, expression of personality, etc.) and embodies many features (e.g., efficient, intelligent, computable, etc.), combining cutting-edge technologies in related fields such as electronic information, sensors and materials. Smart clothing has emerged to meet consumers’ personalized needs in healthcare, work, entertainment, etc., and has rapidly become a hotspot in the clothing industry and research field. However, as smart clothing gets popular, sustainability issues are becoming increasingly prominent during its development and circulation. 
  • 16.8K
  • 19 Apr 2022
Topic Review
The Evolution of Computers
This research explores the evolution of computing from the earliest mechanical devices to the latest cutting-edge technologies. It covers the development of electronic computers in the 1940s and their impact on military, scientific, and business operations. Mainframe computers of the 1950s and 1960s are discussed, including their role in business computing and financial innovation. The personal computer revolution of the 1970s and the rise of mobile computing in the 1980s and 2000s are also examined. The research concludes with a look at the latest developments in computing, including quantum computing and artificial intelligence, and the potential impact of these technologies on society. It emphasizes the importance of working together to address the challenges of emerging technologies and ensuring their ethical and equitable use.
  • 16.8K
  • 22 May 2023
Topic Review
Understanding Sexual Agency
Debates on human agency, not least female and sexual agency, have permeated the social scientific literature and health educational practice during multiple decades now. This article provides a review of recent agency debates, illustrating how criticisms of traditional conceptions of (sexual) agency have led to a notable diversification of the concept. We propose a comprehensive, inclusive description of sexual agency, focusing on the navigation of goals and desires in the wider structural context, and acknowledging the many forms sexual agency may take. We argue there is no simple relation between sexual agency and sexual health. We propose the following description: Sexual agency refers to a continuum of dynamic, everyday, situated modalities of action related to sexuality in which agents navigate (contrarieties between) personal goals, desires and preferences on the one, and personal living conditions, normative expectations and the wider structural context on the other hand. A diversity of internal (e.g. self-identification) and/or external goals (e.g. maintain social relationships or challenge the status quo) motivate and direct sexually agentic behavior. Sexual agency may aim for change as well as for endurance, continuity and stability. It may be overt or tacit. It varies with individual (e.g. temporal orientation) as well as situational variables (e.g. novelty). Sexual agency may reproduce but also resist and renegotiate (aspects of) prevailing norms and the status quo. There is no simple relation between sexual agency and sexual health or well-being. Modalities of action as well as the constructiveness of their (multiple) effects always depend on personal frames of reference as well as on the opportunities and restrictions provided by the (immediate and distant) personal and structural context, including moral and ideological frameworks and dominant sexual stories.
  • 16.7K
  • 21 Oct 2021
Topic Review
Relative Hour (Jewish Law)
Relative hour (Hebrew singular: shaʿah zǝmanit / שעה זמנית; plural: shaʿot - zǝmaniyot / שעות זמניות), sometimes called halachic hour, seasonal hour and variable hour, is a term used in rabbinic Jewish law that assigns 12 hours to each day and 12 hours to each night, all throughout the year. A relative hour has no fixed radical, but changes with the length of each day - depending on summer (when the days are long and the nights are short), and on winter (when the days are short and the nights are long). Even so, in all seasons a day is always divided into 12 hours, and a night is always divided into 12 hours, which inevitably makes for a longer hour or a shorter hour. All of the hours mentioned by the Sages in either the Mishnah or Talmud, or in other rabbinic writings, refer strictly to relative hours. Another feature of this ancient practice is that, unlike the standard modern 12-hour clock that assigns 12 o'clock pm for noon time, in the ancient Jewish tradition noon time was always the sixth hour of the day, whereas the first hour began with the break of dawn, by most exponents of Jewish law, and with sunrise by the Vilna Gaon and Rabbi Hai Gaon. 12:o'clock am (midnight) was also the sixth hour of the night, whereas the first hour of the night began when the first three stars appeared in the night sky.
  • 16.7K
  • 19 Oct 2022
Topic Review
Power Electronic Switches
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less ‘forgotten’ power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch.
  • 16.6K
  • 29 Dec 2020
Topic Review
Magnoliophyta
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (/ˌændʒiəˈspɜːrmiː/), commonly called angiosperms. The term "angiosperm" is derived from the Greek words angeion ('container, vessel') and sperma ('seed'), and refers to those plants that produce their seeds enclosed within a fruit. They are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. Angiosperms were formerly called Magnoliophyta (/mæɡˌnoʊliˈɒfətə, -əˈfaɪtə/). Like gymnosperms, angiosperms are seed-producing plants. They are distinguished from gymnosperms by characteristics including flowers, endosperm within their seeds, and the production of fruits that contain the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous, over 300 million years ago. The closest fossil relatives of flowering plants are uncertain and contentious. The earliest angiosperm fossils are in the form of pollen around 134 million years ago during the Early Cretaceous. Over the course of the Cretaceous, angiosperms explosively diversified, becoming the dominant group of plants across the planet by the end of the period, corresponding with the decline and extinction of previously widespread gymnosperm groups. The origin and diversification of the angiosperms is often known as "Darwin's abominable mystery".
  • 16.6K
  • 28 Nov 2022
Topic Review
Fifth Generation Computer
The Fifth Generation Computer Systems (FGCS) was an initiative by Japan's Ministry of International Trade and Industry (MITI), begun in 1982, to create computers using massively parallel computing and logic programming. It was to be the result of a government/industry research project in Japan during the 1980s. It aimed to create an "epoch-making computer" with supercomputer-like performance and to provide a platform for future developments in artificial intelligence. There was also an unrelated Russian project also named as a fifth-generation computer (see Kronos (computer)). Ehud Shapiro, in his "Trip Report" paper (which focused the FGCS project on concurrent logic programming as the software foundation for the project), captured the rationale and motivations driving this project: The term "fifth generation" was intended to convey the system as being advanced. In the history of computing hardware, computers using vacuum tubes were called the first generation; transistors and diodes, the second; integrated circuits, the third; and those using microprocessors, the fourth. Whereas previous computer generations had focused on increasing the number of logic elements in a single CPU, the fifth generation, it was widely believed at the time, would instead turn to massive numbers of CPUs for added performance. The project was to create the computer over a ten-year period, after which it was considered ended and investment in a new "sixth generation" project would begin. Opinions about its outcome are divided: either it was a failure, or it was ahead of its time.
  • 16.6K
  • 21 Oct 2022
Topic Review
Ballistic Missile
A ballistic missile follows a ballistic trajectory to deliver one or more warheads on a predetermined target. These weapons are only guided during relatively brief periods of flight—most of their trajectory is unpowered, being governed by gravity and air resistance if in the atmosphere. Shorter range ballistic missiles stay within the Earth's atmosphere, while longer-ranged intercontinental ballistic missiles (ICBMs), are launched on a sub-orbital flight trajectory and spend most of their flight out of the atmosphere. These weapons are in a distinct category from cruise missiles, which are aerodynamically guided in powered flight.
  • 16.6K
  • 05 Nov 2022
Topic Review
Overhead Camshaft
Overhead camshaft, commonly abbreviated to OHC, is a valvetrain configuration which places the camshaft of an internal combustion engine of the reciprocating type within the cylinder heads ("above" the pistons and combustion chambers) and drives the valves or lifters in a more direct manner compared with overhead valves (OHV) and pushrods.
  • 16.5K
  • 21 Nov 2022
Topic Review
List of Anatomy Mnemonics
This is a list of human anatomy mnemonics, categorized and alphabetized. For mnemonics in other medical specialties, see this list of medical mnemonics.
  • 16.5K
  • 24 Nov 2022
Topic Review
Boarhounds
Boarhounds are hunting dogs bred for hunting wild boar. The most commonly used for this purpose are hounds, dachshunds or terriers, but pointers, spitz or retrievers can also be used. The dog should be courageous, persistent, passionate, disciplined, sharp and obedient. Hunting in this group of dogs can be carried out individually and for such breeds are used small and collective breeds as well as medium and large breeds of dogs.
  • 16.5K
  • 16 Jun 2021
Topic Review
DPPH Radical Scavenging Assay
The 1,1-diphenyl-2-picrylhydrazil (DPPH) radical removal is one of the most widely applied and used methods in food and pharmaceutical applications. DPPH method gives a better response for mostly phenolic compounds and then for compounds with limited polarity. In the case of polar and phenolic compounds, adding water to the reaction medium, that is, aqueous methanol, gives better results. When testing low-polarity compounds, ethyl acetate with a radical is suitable. DPPH reaction rates depend on the steric accessibility of the radical site rather than the chemical properties of the tested antioxidant compounds. The rate at which DPPH reacts with antioxidants depends on the varying ratios of mixed single-electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms. The reaction mechanisms of DPPH∙ scavenging and responses are modified by many environmental and experimental factors.
  • 16.5K
  • 08 Sep 2023
Biography
René Sotelo
René Sotelo (6 November 1962) is a Venezuelan robotic surgeon, urologist-oncologist and university professor.[1][2] Sotelo received his medical degree from Central University of Venezuela[3] and his residency in General Surgery and Urology was at Domingo Luciani Hospital, Venezuela. He completed fellowship in Urologic Oncology at the Hospital Padre Machado in Caracas, Venezuela; training in
  • 16.4K
  • 18 Nov 2022
Topic Review
Coumarin
Coumarin (2H-1-benzopyran-2-one) is an oxygen containing heterocycle and belongs to the subcategory of lactones.
  • 16.4K
  • 06 Jan 2021
Topic Review
Cost of Electricity by Source
The distinct methods of electricity generation can incur significantly different costs and these costs can occur at significantly different times relative to when the power is used. Also, calculations of these costs can be made at the point of connection to a load or to the electricity grid (ie they may or may not include the transmission costs). The costs include the initial capital, and the costs of continuous operation, fuel, and maintenance as well as the costs of de-commissioning and remediating any environmental damage. For comparing different methods, it is useful to compare costs per unit of energy which is typically given per kilowatt-hour or megawatt-hour. This type of calculation assists policymakers, researchers and others to guide discussions and decision-making but is usually complicated by the need to take account of differences in timing by means of a discount rate.
  • 16.4K
  • 13 Oct 2022
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