Summary

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.

Expand All
Entries
Topic Review
List of German Aircraft Projects, 1939–45
The aircraft in this list include prototype versions of aircraft used by the German Luftwaffe during World War II and unfinished wartime experimental programmes. In the former, development can stretch back to the 1920s and in the latter the project must have started between 1939-1945.
  • 5.2K
  • 14 Oct 2022
Topic Review
Death of Ali Abdulhadi Mushaima
Ali Abdulhadi Saleh Jafar Mushaima (Arabic: علي عبدالهادي صالح جعفر مشيمع) (26 August 1989 – 14 February 2011) was a 21-year-old Bahraini who on Monday 14 February 2011, the "Bahraini Day of Rage", became the first fatality of the Bahraini Uprising. He died on his way to hospital from injuries he received when he was hit in the back by birdshot pellets fired from close range (two to five meters) by security forces (riot police)(pp228–9) during the Bahraini uprising (2011–present). According to Nabeel Rajab, head of Bahrain Centre for Human Rights, Mushaima was participating in a protest in Al Daih, in Manama's outskirt, when he was shot. In a rare televised speech the King of Bahrain, Hamad bin Isa Al Khalifa, announced that the deaths of Ali Abdulhadi Mushaima and Fadhel Al-Matrook would be investigated. Bahrain's Interior Minister said that legal steps would be taken if the use of the weapon had been unwarranted. Details of the investigation were disclosed in the report of the Bahrain Independent Commission of Inquiry, established by King Hamad to look into events in the Bahraini uprising. The investigation failed to identify any culprits in the killing of Mushaima.(p229) The Commission concluded that Mushaima's death resulted from the "use of excessive force by police officers," and "that there was no justification for the use of lethal force."(p229)
  • 1.0K
  • 14 Oct 2022
Topic Review
Nitroaldol Reaction
The Henry Reaction (also referred to as the nitro-aldol reaction) is a classic carbon–carbon bond formation reaction in organic chemistry. Discovered in 1895 by the Belgian chemist Louis Henry (1834-1913), it is the combination of a nitroalkane and an aldehyde or ketone in the presence of a base to form β-Nitro alcohols. This type of reaction is commonly referred to as a "nitro-aldol" reaction (nitroalkane, aldehyde, and alcohol) It is nearly analogous to the aldol reaction that had been discovered 23 years prior that couples two carbonyl compounds to form β-hydroxy carbonyl compounds known as "aldols" (aldehyde and alcohol). The Henry reaction is a useful technique in the area of organic chemistry due to the synthetic utility of its corresponding products, as they can be easily converted to other useful synthetic intermediates. These conversions include subsequent dehydration to yield nitroalkenes, oxidation of the secondary alcohol to yield α-nitro ketones, or reduction of the nitro group to yield β-amino alcohols. Many of these uses have been exemplified in the syntheses of various pharmaceuticals including the β-blocker (S)-propranolol, the HIV protease inhibitor Amprenavir (Vertex 478), and construction of the carbohydrate subunit of the anthracycline class of antibiotics, L-Acosamine. The synthetic scheme of the L-Acosamine synthesis can be found in the Examples section of this article.
  • 2.9K
  • 14 Oct 2022
Topic Review
Hypervitaminosis D
Hypervitaminosis D is a state of vitamin D toxicity. The normal range for blood concentration is 30.0 to 74.0 nanograms per milliliter (ng/mL).
  • 813
  • 14 Oct 2022
Topic Review
Protein Chemical Shift Re-referencing
Protein chemical shift re-referencing is a post-assignment process of adjusting the assigned NMR chemical shifts to match IUPAC and BMRB recommended standards in protein chemical shift referencing. In NMR chemical shifts are normally referenced to an internal standard that is dissolved in the NMR sample. These internal standards include tetramethylsilane (TMS), 4,4-dimethyl-4-silapentane-1-sulfonic acid (DSS) and trimethylsilyl propionate (TSP). For protein NMR spectroscopy the recommended standard is DSS, which is insensitive to pH variations (unlike TSP). Furthermore, the DSS 1H signal may be used to indirectly reference 13C and 15N shifts using a simple ratio calculation . Unfortunately, many biomolecular NMR spectroscopy labs use non-standard methods for determining the 1H, 13C or 15N “zero-point” chemical shift position. This lack of standardization makes it difficult to compare chemical shifts for the same protein between different laboratories. It also makes it difficult to use chemical shifts to properly identify or assign secondary structures or to improve their 3D structures via chemical shift refinement. Chemical shift re-referencing offers a means to correct these referencing errors and to standardize the reporting of protein chemical shifts across laboratories.
  • 739
  • 14 Oct 2022
Topic Review
Forgiveness Scale
A forgiveness scale is a psychological test that attempts to measure a person's willingness to forgive. A true definition of forgiveness is debated by many researchers, yet Hargrave suggests that forgiveness refers to releasing resentment towards an offender. Forgiveness is a complex phenomenon which involves cognitive, affective, behavioural, motivational, decisional and interpersonal elements. Forgiveness is thought to be central to human functioning and important in restoring interpersonal relationships. It is an effective intervention to problems caused by anger, depression, drug abuse, guilt and moral development. Due to the different conceptualisations of forgiveness, different scales have been developed to measure the ability in different ways. Examples of forgiveness scales include the Forgiveness scale of the Interpersonal Relationship Resolution Scale; the Marital Offence-Specific Forgiveness Scale; the Workplace Forgiveness Scale; and the Tendency to Forgive scale. Forgiveness can also be measured via methods which are not empirical scales. These may come in the form of biological measures; such as chemical, central and peripheral physiological measures, as well as behavioural measures; and measures of self forgiveness. Studies have found that compared to participants without past suicide attempts, those with past suicide attempts scored on the Forgiveness Scale as being significantly less believing of forgiveness by others, were less likely to forgive themselves, and to a lesser degree, were less forgiving of others.
  • 2.4K
  • 14 Oct 2022
Topic Review
Ridge
Ridges (regions of increased gene expression) are domains of the genome with a high gene expression; the opposite of ridges are antiridges. The term was first used by Caron et al. in 2001. Characteristics of ridges are: Gene dense, Contain many C and G nucleobases, Genes have short introns, High SINE repeat density, Low LINE repeat density.
  • 959
  • 18 Oct 2022
Topic Review
Engine Control Unit
An engine control unit (ECU), also commonly called an engine control module (ECM) is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by reading values from a multitude of sensors within the engine bay, interpreting the data using multidimensional performance maps (called lookup tables), and adjusting the engine actuators. Before ECUs, air–fuel mixture, ignition timing, and idle speed were mechanically set and dynamically controlled by mechanical and pneumatic means. If the ECU has control over the fuel lines, then it is referred to as an electronic engine management system (EEMS). The fuel injection system has the major role of controlling the engine's fuel supply. The whole mechanism of the EEMS is controlled by a stack of sensors and actuators.
  • 5.3K
  • 14 Oct 2022
Topic Review
New ICT
New ICT is an open, customer-driven ecosystem which is proposed by the information technology company Huawei. In simple terms, the new ICT fully converges IT and CT technologies to offer large-scale communication, storage, and processing capabilities. The new ICT works as a flexible, agile platform to adapt to ever-changing business goals, system environments, and application configurations. The new ICT era has three compelling characteristics: business-driven development, agile innovation, and a new ecosystem.
  • 566
  • 14 Oct 2022
Topic Review
Earth Hour
Earth Hour is a worldwide movement organized by the World Wildlife Fund (WWF). The event is held annually, encouraging individuals, communities, and businesses to turn off non-essential electric lights, for one hour, from 8:00 to 9:00 p.m. on the last Saturday of March, as a symbol of commitment to the planet. It was started as a lights-off event in Sydney, Australia, in 2007. Occasionally, in years when Holy Saturday falls on the last Saturday of March, Earth Hour is moved a week early rather than its usual date.
  • 1.3K
  • 14 Oct 2022
  • Page
  • of
  • 863

Other Entry Collections

>>