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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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Mapogo Lion Coalition
The Mapogo lion coalition was a band of male South African lions that controlled the Sabi Sand region in Kruger National Park. The coalition became infamous for their sheer power and strength in taking over and dominating an area of approximately 70,000 ha (170,000 acres). It is believed the Mapogos killed in excess of 100 lions and cubs in a little over a year. The statistics may be higher given their coverage of such large territories. At its peak, the coalition consisted of six males - the leader Makulu (also spelled as Makhulu), Rasta, Scar, Pretty Boy, Kinky Tail and Mr. T.
  • 21.8K
  • 09 Oct 2022
Topic Review
Snakes and Ladders
Snakes and Ladders, known originally as Moksha Patam, is an ancient Indian board game for two or more players regarded today as a worldwide classic. It is played on a game board with numbered, gridded squares. A number of "ladders" and "snakes" are pictured on the board, each connecting two specific board squares. The object of the game is to navigate one's game piece, according to die rolls, from the start (bottom square) to the finish (top square), helped by climbing ladders but hindered by falling down snakes. The game is a simple race based on sheer luck, and it is popular with young children. The historic version had its roots in morality lessons, on which a player's progression up the board represented a life journey complicated by virtues (ladders) and vices (snakes). The game is also sold under other names such as Chutes and Ladders, Bible Ups and Downs, etc., some with a morality motif; a morality Chutes and Ladders was published by Milton Bradley starting from 1943.
  • 19.2K
  • 09 Oct 2022
Topic Review
Solid Phase Extraction
Solid-phase extraction (SPE) is an extractive technique by which compounds that are dissolved or suspended in a liquid mixture are separated from other compounds in the mixture according to their physical and chemical properties. Analytical laboratories use solid phase extraction to concentrate and purify samples for analysis. Solid phase extraction can be used to isolate analytes of interest from a wide variety of matrices, including urine, blood, water, beverages, soil, and animal tissue. SPE uses the affinity of solutes dissolved or suspended in a liquid (known as the mobile phase) for a solid through which the sample is passed (known as the stationary phase) to separate a mixture into desired and undesired components. The result is that either the desired analytes of interest or undesired impurities in the sample are retained on the stationary phase. The portion that passes through the stationary phase is collected or discarded, depending on whether it contains the desired analytes or undesired impurities. If the portion retained on the stationary phase includes the desired analytes, they can then be removed from the stationary phase for collection in an additional step, in which the stationary phase is rinsed with an appropriate eluent. Many of the adsorbents/materials are the same as in chromatographic methods, but SPE is distinctive, with aims separate from chromatography, and so has a unique niche in modern chemical science.
  • 2.1K
  • 29 Sep 2022
Topic Review
Congregation for the Doctrine of the Faith
The Congregation for the Doctrine of the Faith (Latin: Congregatio pro Doctrina Fidei; CDF) is the oldest among the nine congregations of the Roman Curia. It was founded to defend the church from heresy; today, it is the body responsible for promulgating and defending Catholic doctrine. Formerly known as the Supreme Sacred Congregation of the Roman and Universal Inquisition, it is informally known in many Catholic countries as the Holy Office, and between 1908 and 1965 was officially known as the Supreme Sacred Congregation of the Holy Office. Founded by Pope Paul III in 1542, the congregation's sole objective is to "spread sound Catholic doctrine and defend those points of Christian tradition which seem in danger because of new and unacceptable doctrines." Its headquarters are at the Palace of the Holy Office, just outside Vatican City. The congregation employs an advisory board including cardinals, bishops, priests, lay theologians, and canon lawyers. The current Prefect is Archbishop Luis Ladaria Ferrer, who was appointed by Pope Francis for a five-year term beginning July 2017.
  • 6.5K
  • 29 Sep 2022
Topic Review
Islamic State
An Islamic state is a form of government based on Islamic law. As a term, it has been used to describe various historical polities and theories of governance in the Islamic world. As translation of the Arabic term dawlah islāmiyyah (Arabic: دولة إسلامية) it refers to a modern notion associated with political Islam (Islamism). The concept of the modern Islamic state has been articulated and promoted by ideologues such as Abul A'la Maududi, Ayatollah Ruhollah Khomeini, Israr Ahmed or Sayyid Qutb. Implementation of Islamic law plays an important role in modern theories of the Islamic state, as it did in classical Islamic political theories. However, the modern theories also make use of notions that did not exist before the modern era. Today, many Muslim countries have incorporated Islamic law, wholly or in part, into their legal systems. Certain Muslim states have declared Islam to be their state religion in their constitutions, but do not apply Islamic law in their courts. Islamic states which are not Islamic monarchies are usually referred to as Islamic republics.
  • 5.3K
  • 29 Sep 2022
Topic Review
Nag (Missile)
The Nag missile (IAST: Nāga; en: Cobra), also called "Prospina" for the land-attack version, is an India n third-generation, all-weather, fire-and-forget, lock-on after launch, anti-tank guided missile (ATGM) with an operational range of 500 m to 20 km. It has a single-shot hit probability of 90% and a ten-year, maintenance-free shelf life. The Nag has five variants under development: a land version, for a mast-mounted system; the helicopter-launched Nag (HELINA) also known as Dhruvastra; a "man-portable" version (MPATGM); an air-launched version which will replace the current imaging infra-red (IIR) to millimetric-wave (mmW) active radar homing seeker; and the Nag Missile Carrier (NAMICA) "tank buster", which is a modified BMP-2 Infantry Fighting Vehicle (IFV) produced under license in India by Ordnance Factory Medak (OFMK). Development of the Nag is part of the Integrated Guided Missile Development Program (IGMDP), run by Defence Research and Development Organisation (DRDO). It is manufactured by Bharat Dynamics Limited (BDL). India's Ministry of Defence (MoD) announced on 19 July 2019 that the missile was ready for production. The Defence Research and Development Organization (DRDO) successfully completed the final trial of Nag anti-tank missile using a live warhead on a dud tank at Pokhran army ranges at 6.45 am on Oct 21, 2020.
  • 8.8K
  • 09 Oct 2022
Topic Review
Firmware
In computing, firmware is a specific class of computer software that provides the low-level control for a device's specific hardware. Firmware, such as the BIOS of a personal computer, may contain basic functions of a device, and may provide hardware abstraction services to higher-level software such as operating systems. For less complex devices, firmware may act as the device's complete operating system, performing all control, monitoring and data manipulation functions. Typical examples of devices containing firmware are embedded systems, home and personal-use appliances, computers, and computer peripherals. Firmware is held in non-volatile memory devices such as ROM, EPROM, EEPROM, and Flash memory. Updating firmware requires ROM integrated circuits to be physically replaced, or EPROM or flash memory to be reprogrammed through a special procedure. Some firmware memory devices are permanently installed and cannot be changed after manufacture. Common reasons for updating firmware include fixing bugs or adding features to the device.
  • 2.3K
  • 29 Sep 2022
Topic Review
DASH7 Alliance
The DASH7 Alliance (D7A) is a group of companies and universities managing the evolution of the Dash7 Alliance protocol. The goal of the group is to create a complete interoperable RF technology to exchange data for wireless sensor networks and devices at a block scale (300m–1 km). Initially created with the participation of the US DoD and Lockheed Martin in 2009, the group evolved from RFID military needs (ISO-18000-7 support group role), to an industrial generic requirement. The Dash7 Alliance continued to forge an extensive experience in high reliability 433 MHz networks and extended it to 868/915 MHz. Unlike other protocols, Dash7 Alliance published layered based protocols to ensure interoperability up to the file exchange layers. A complete Open Source implementation, OSS-7, as well as industrial implementations enabled to create a certification lab and organize regular plugfest. The DASH7 Alliance was a privately held, 501(c)3 not-for-profit trade association founded in February 2009 and headquartered in San Ramon, California. Since 2015, it is a European NGO based in Brussels, Belgium.
  • 1.1K
  • 29 Sep 2022
Topic Review
Saltation
In biology, saltation (from la saltus 'leap, jump') is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps. Speciation, such as by polyploidy in plants, can sometimes be achieved in a single and in evolutionary terms sudden step. Evidence exists for various forms of saltation in a variety of organisms.
  • 5.8K
  • 29 Sep 2022
Topic Review
Eukaryotic Ribosome (80S)
Ribosomes are a large and complex molecular machine that catalyzes the synthesis of proteins, referred to as translation. The ribosome selects aminoacylated transfer RNAs (tRNAs) based on the sequence of a protein-encoding messenger RNA (mRNA) and covalently links the amino acids into a polypeptide chain. Ribosomes from all organisms share a highly conserved catalytic center. However, the ribosomes of eukaryotes (animals, plants, fungi, and many unicellular organisms with a nucleus) are much larger than prokaryotic (bacterial and archaeal) ribosomes and subject to more complex regulation and biogenesis pathways. Eukaryotic ribosomes are also known as 80S ribosomes, referring to their sedimentation coefficients in Svedberg units, because they sediment faster than the prokaryotic (70S) ribosomes. Eukaryotic ribosomes have two unequal subunits, designated small subunit (40S) and large subunit (60S) according to their sedimentation coefficients. Both subunits contain dozens of ribosomal proteins arranged on a scaffold composed of ribosomal RNA (rRNA). The small subunit monitors the complementarity between tRNA anticodon and mRNA, while the large subunit catalyzes peptide bond formation.
  • 8.7K
  • 14 Apr 2023
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