The citric acid cycle (CAC)—also known as the Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins. The Krebs cycle is used by organisms that respire (as opposed to organisms that ferment) to generate energy, either by anaerobic respiration or aerobic respiration. In addition, the cycle provides precursors of certain amino acids, as well as the reducing agent NADH, that are used in numerous other reactions. Its central importance to many biochemical pathways suggests that it was one of the earliest components of metabolism and may have originated abiogenically. Even though it is branded as a 'cycle', it is not necessary for metabolites to follow only one specific route; at least three alternative segments of the citric acid cycle have been recognized.The name of this metabolic pathway is derived from the citric acid (a tricarboxylic acid, often called citrate, as the ionized form predominates at biological pH) that is consumed and then regenerated by this sequence of reactions to complete the cycle. The...

Shaki Waterfall (Armenian: Շաքիի ջրվեժ) is a waterfall in Armenia, with a height of 18 m. It is located in Syunik Province.The Shaki Waterfall is situated 6 km from the town of Sisian. On the left side of the river Vorotan's gorge, basalt lava flows have solidified to form a ledge 18 meters high from which the waterfall cascades down. Gallery See also Geography of ArmeniaReferences External links Media related to Shaki Waterfall at Wikimedia Commons

The Odyssey (; Ancient Greek: Ὀδύσσεια, romanized: Odýsseia, Attic Greek: [o.dýs.seː.a]) is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the Iliad, the poem is divided into 24 books. It follows the Greek hero Odysseus, king of Ithaca, and his journey home after the Trojan War. After the war, which lasted ten years, his journey lasted for ten additional years, during which time he encountered many perils and all his crew mates were killed. In his absence, Odysseus was assumed dead, and his wife Penelope and son Telemachus had to contend with a group of unruly suitors who were competing for Penelope's hand in marriage. The...

The Odyssey (; Ancient Greek: Ὀδύσσεια, romanized: Odýsseia, Attic Greek: [o.dýs.seː.a]) is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the Iliad, the poem is divided into 24 books. It follows the Greek hero Odysseus, king of Ithaca, and his journey home after the Trojan War. After the war, which lasted ten years, his journey lasted for ten additional years, during which time he encountered many perils and all his crew mates were killed. In his absence, Odysseus was assumed dead, and his wife Penelope and son Telemachus had to contend with a group of unruly suitors who were competing for Penelope's hand in marriage. The...

The Odyssey (; Ancient Greek: Ὀδύσσεια, romanized: Odýsseia, Attic Greek: [o.dýs.seː.a]) is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the Iliad, the poem is divided into 24 books. It follows the Greek hero Odysseus, king of Ithaca, and his journey home after the Trojan War. After the war, which lasted ten years, his journey lasted for ten additional years, during which time he encountered many perils and all his crew mates were killed. In his absence, Odysseus was assumed dead, and his wife Penelope and son Telemachus had to contend with a group of unruly suitors who were competing for Penelope's hand in marriage. The...

In DOS memory management, extended memory refers to memory above the first megabyte (220 bytes) of address space in an IBM PC or compatible with an 80286 or later processor. The term is mainly used under the DOS and Windows operating systems. DOS programs, running in real mode or virtual x86 mode, cannot directly access this memory, but are able to do so through an application programming interface called the Extended Memory Specification (XMS). This API is implemented by a driver (such as HIMEM.SYS) or the operating system, which takes care of memory management and copying memory between conventional and extended memory, by temporarily switching the processor into protected mode. In this context, the term "extended memory" may refer to either the whole of the extended memory or only the portion available through this API. Extended memory can also be accessed directly by DOS programs running in protected mode using VCPI or DPMI, two (different and incompatible) methods of using protected mode under DOS. Extended memory should not be confused with expanded memory (EMS), an earlier method for expanding the IBM PC...

The Journal of Medical Ethics is a monthly peer-reviewed academic journal covering the field of bioethics that was established in 1975. According to the Journal Citation Reports, the journal has a 2019 impact factor of 2.021, ranking it fourth out of 16 journals in the category "Medical Ethics" and 11th out of 55 journals in the category "Ethics". Editors-in-chief The editor-in-chief is John McMillan (University of Otago). Previous editors have been: Julian Savulescu (University of Oxford) (2011–2018 and 2001–2004), Søren Holm (Cardiff University) and John Harris (University of Manchester, (jointly, 2004–2011), Raanan Gillon (Imperial College London, 1980–2001), and Alastair Campbell (University of Edinburgh, 1975–1980, founding editor). See also List of ethics journalsReferences External links Official website

Hydrology (from Ancient Greek ὕδωρ (húdōr) 'water', and -λογία (-logía) 'study of') is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and drainage basin sustainability. A practitioner of hydrology is called a hydrologist. Hydrologists are scientists studying earth or environmental science, civil or environmental engineering, and physical geography. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management.Hydrology subdivides into surface water hydrology, groundwater hydrology (hydrogeology), and marine hydrology. Domains of hydrology include hydrometeorology, surface hydrology, hydrogeology, drainage-basin management, and water quality. Oceanography and meteorology...

A Kendrick extrication device (KED) is a device used in extrication of victims of traffic collisions from motor vehicles. Commonly carried on ambulances, a KED is typically used by an emergency medical technician, paramedic, or another first responder. It was originally designed for extrication of race car drivers. Typically used in conjunction with a cervical collar, a KED is a semi-rigid brace that secures the head, neck and torso in an anatomically neutral position. Its use is claimed to reduce the possibility of additional injuries to these regions during extrication, although its value has been questioned, as there is a lack of evidence to support its use. The original KED was designed by Richard Kendrick in 1978. Description Typically there are two head straps, three torso straps, and two legs straps which are used to adequately secure the KED to the victim. Unlike a long spine board or litter, the KED uses a series of wooden or polymer bars in a nylon jacket, allowing the responders to immobilize the neck and upper spine and remove the victim from the vehicle or other confined space. Although a KED can also be used...

21st century skills comprise skills, abilities, and learning dispositions that have been identified as being required for success in 21st century society and workplaces by educators, business leaders, academics, and governmental agencies. This is part of a growing international movement focusing on the skills required for students to master in preparation for success in a rapidly changing, digital society. Many of these skills are also associated with deeper learning, which is based on mastering skills such as analytic reasoning, complex problem solving, and teamwork. These skills differ from traditional academic skills in that they are not primarily content knowledge-based.During the latter decades of the 20th century and into the 21st century, society has undergone an accelerating pace of change in economy and technology. Its effects on the workplace, and thus on the demands on the educational system preparing students for the workforce, have been significant in several ways. Beginning in the 1980s, government, educators, and major employers issued a series of reports identifying key skills and implementation strategies to steer students and workers towards meeting...