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Topic Review
Freeze-Drying of Foods
Freeze-drying is a process in which water is sublimated by the direct transition of water from solid (ice) to vapor, thus omitting the liquid state, and then desorbing water from the “dry” layer.
  • 3.4K
  • 16 Nov 2020
Topic Review
Embryonic Development
In developmental biology, embryonic development, also known as embryogenesis, is the development of an animal or plant embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell, (spermatozoon). Once fertilized, the ovum becomes a single diploid cell known as a zygote. The zygote undergoes mitotic divisions with no significant growth (a process known as cleavage) and cellular differentiation, leading to development of a multicellular embryo after passing through an organizational checkpoint during mid-embryogenesis. In mammals, the term refers chiefly to the early stages of prenatal development, whereas the terms fetus and fetal development describe later stages.
  • 3.4K
  • 28 Apr 2023
Topic Review
PDP-10
Digital Equipment Corporation (DEC)'s PDP-10, later marketed as the DECsystem-10, is a mainframe computer family manufactured beginning in 1966 and discontinued in 1983. 1970s models and beyond were marketed under the DECsystem-10 name, especially as the TOPS-10 operating system became widely used. The PDP-10's architecture is almost identical to that of DEC's earlier PDP-6, sharing the same 36-bit word length and slightly extending the instruction set (but with improved hardware implementation). Some aspects of the instruction set are unusual, most notably the byte instructions, which operate on bit fields of any size from 1 to 36 bits inclusive, according to the general definition of a byte as a contiguous sequence of a fixed number of bits. The PDP-10 was found in many university computing facilities and research labs during the 1970s, the most notable being Harvard University's Aiken Computation Laboratory, MIT's AI Lab and Project MAC, Stanford's SAIL, Computer Center Corporation (CCC), ETH (ZIR), and Carnegie Mellon University. Its main operating systems, TOPS-10 and TENEX, were used to build out the early ARPANET. For these reasons, the PDP-10 looms large in early hacker folklore. Projects to extend the PDP-10 line were eclipsed by the success of the unrelated VAX superminicomputer, and the cancellation of the PDP-10 line was announced in 1983. By late 1980 DEC reportedly had sold "about 1500 DECsystem-10s."
  • 3.4K
  • 04 Nov 2022
Topic Review
Online Diary
An online diary is a personal diary or journal that is published on the World Wide Web on a personal website or a diary-hosting website.
  • 3.4K
  • 02 Nov 2022
Topic Review
The Biomechanics of Cartilage
Articular cartilage (AC) sheathes joint surfaces and minimizes friction in diarthrosis. The resident cell population, chondrocytes, are surrounded by an extracellular matrix and a multitude of proteins, which bestow their unique characteristics. AC is characterized by a zonal composition (superficial (tangential) zone, middle (transitional) zone, deep zone, calcified zone) with different mechanical properties. An overview is given about different testing (load tests) methods as well as different modeling approaches.
  • 3.4K
  • 14 Apr 2021
Topic Review
Kaharingan
Kaharingan is a folk religion professed by many Dayaks in Kalimantan, Indonesia; particularly Central Kalimantan, although many have converted to Christianity or Islam. The word means life, and this belief system includes a concept of a supreme deity—although this may be the result of the need to conform to the idea of "One Supreme God" (Ketuhanan yang Maha Esa), which is the first principle of the Indonesian state ideology Pancasila. Hindu-Javanese influence can be seen in this religion, and the Indonesian government views it as a form of Hinduism because the Indonesian government recognizes only six official religions, and Kaharingan is not one of them. The main festival of Kaharingan is the Tiwah festival, which lasts for thirty days, and involves the sacrifice of many animals like buffaloes, cows, pigs and chickens, as offerings to the Supreme God. The supreme God in Kaharingan is called Ranying. In addition, the religion has ritual offerings called Yadnya, places of worship called Balai Basarah or Balai Kaharingan and a holy book called Panaturan, Talatah Basarah (group of prayers) and Tawar (a guide to seek God's help by giving rice).
  • 3.4K
  • 02 Nov 2022
Topic Review
Energy Condition
In relativistic classical field theories of gravitation, particularly general relativity, an energy condition is a generalization of the statement "the energy density of a region of space cannot be negative" in a relativistically-phrased mathematical formulation. There are multiple possible alternative ways to express such a condition such that can be applied to the matter content of the theory. The hope is then that any reasonable matter theory will satisfy this condition or at least will preserve the condition if it is satisfied by the starting conditions. Energy conditions are not physical constraints per se, but are rather mathematically imposed boundary conditions that attempt to capture a belief that "energy should be positive". Many energy conditions are known to not correspond to physical reality—for example, the observable effects of dark energy are well-known to violate the strong energy condition. In general relativity, energy conditions are often used (and required) in proofs of various important theorems about black holes, such as the no hair theorem or the laws of black hole thermodynamics.
  • 3.4K
  • 07 Nov 2022
Topic Review
α-Lactalbumin
α-Lactalbumin (α-LA) is a small (Mr 14,200), acidic (pI 4-5), Ca2+-binding protein. α-LA is a regulatory component of lactose synthase enzyme system. α-LA is very important in infant nutrition since it constitutes a large part of the whey and total protein in human milk. The protein possesses a single strong Ca2+-binding site, which can also bind Mg2+, Mn2+, Na+, K+, and some other metal cations. It contains several distinct Zn2+-binding sites. Physical properties of α-LA strongly depend on the occupation of its metal binding sites by metal ions. In the absence of bound metal ions α-LA is in the molten globule-like state. The binding of metal ions, and especially of Ca2+, increases stability of α-LA against action of heat, various denaturing agents, and proteases, while the binding of Zn2+ to the Ca2+-loaded protein decreases its stability and causes its aggregation. The thermal unfolding of apo-α-LA takes place in the temperature region from 10 to 30 °C. The binding of Ca2+ under the conditions of low ionic strength shifts the thermal transition to higher temperatures by more than 40 °C. The binding of Mg2+, Na+, and K+ increases protein stability as well. The stronger an ion binds to the protein, the more pronounced the thermal transition shift. All four classes of surfactants (anionic, cationic, non-ionic, and zwitterionic) denature α-LA and the denaturation involves at least one intermediate. The position of any denaturation transition in α-LA (half-transition temperature, half-transition pressure, half-transition denaturant concentration) depends upon metal ion concentration in solution (especially if this metal ion is Ca2+). Therefore, values of denaturation temperature or urea or guanidine hydrochloride denaturing concentration are relatively meaningless for α-LA without specifying the metal ion content(s) and their solution concentration(s). At a neutral or slightly acidic pH at a physiological temperature, α-LA can associate with membranes. The conformations of the membrane-bound protein range from native-like to molten globule-like states. At a low pH, α-LA penetrates the interior of the negatively charged membranes and exhibits a molten globule conformation. Depending on external conditions, α-LA can form amyloid fibrils, amorphous aggregates, nanoparticles, and nanotubes. At pH 2, α-LA in the classical molten globule conformation can form amyloid fibrils. Some of these aggregated states of α-LA (nanoparticles, nanotubes) can be used in practical applications such as drug delivery to tissues and organs. The structure and self-assembly behavior of α-LA are governed by a subtle balance between hydrophobic and polar interactions and this balance can be finely tuned through the addition of selected substances. Small size nanoparticles of α-LA (100 to 200 nm) can be obtained with the use of various desolvating agents. Partially hydrolyzed α-LA can form nanotubes. α-LA and some of its fragments possess bactericidal and antiviral activities. Complexes of partially unfolded α-LA with oleic acid showed significant cytotoxicity to various tumor and bacterial cells. α-LA in such complexes plays a role of a delivery carrier of cytotoxic fatty acid molecules into tumor cells across the cell membrane. Cytotoxic protein–oleic acid complexes possess a common core-shell structure, where an oily core is made of a micellar oleic acid, whereas a proteinaceous shell, which stabilizes the oleic acid micelle, is formed from the flexible, partially unfolded proteins. These complexes called liprotides (lipids and partially denatured proteins), which are potential novel anti-tumorous drugs, can be considered as molten globular containers filled with the toxic oil.
  • 3.4K
  • 31 Aug 2020
Topic Review
Discover Card
Discover is a credit card brand issued primarily in the United States. It was introduced by Sears in 1985. When launched, Discover did not charge an annual fee and offered a higher-than-normal credit limit, features that were disruptive to the existing credit card industry. A subsequent innovation was "Cashback Bonus" on purchases. Most cards with the Discover brand are issued by Discover Bank, formerly the Greenwood Trust Company. Discover transactions are processed through the Discover Network payment network. In 2005, Discover Financial Services acquired Pulse, an electronic funds transfer network, allowing it to market and issue debit and ATM cards. In February 2006, Discover Financial Services announced that it would begin offering Discover Debit cards to other financial institutions, made possible by the acquisition of Pulse. Discover is the fourth largest credit card brand in the U.S., behind Visa, MasterCard and American Express, with nearly 44 million cardholders.
  • 3.4K
  • 01 Nov 2022
Topic Review
Association between Membrane Proteins and Disease
Cell membranes, including membrane carrier proteins, membrane channel proteins and ATP drive pumps, are the main transporters. Membrane transporters have wide, but specific tissue distributions. They can impact on multiple endogenous and xenobiotic processes. Transport proteins constitute approximately 10% of most proteomes and play vital roles in the translocation of solutes across the membranes of all organisms. The receptor proteins on the cell membrane are also important structures involved in substrate transport and signal communication. The obstacles of cell transport-related proteins directly lead to the lack or excess of certain substances in cells.
  • 3.4K
  • 04 Nov 2021
Topic Review
Rada (Fiqh)
Raḍāʿ or riḍāʿa (Arabic: رضاع, رضاعة  pronounced [rɪˈdˤɑːʕ(æ)], "breastfeeding") is a technical term in Sunni Islamic jurisprudence (fiqh) meaning "the suckling which produces the legal impediment to marriage of foster-kinship", and refers to the fact that under Sunni jurispurdence, a wet nurse is considered related to the infant she nurses. The term derives from the infinitive noun of the Arabic word radiʿa or radaʿa ("he sucked the breast of his mother"). Often it is translated as "fosterage" or "milk kinship". The concept of radāʿ derives from Islamic and pre-Islamic notions concerning the state of blood relations whereby a wet nurse (and her close relations) and the baby she is nursing (and his or her close family) are deemed related to one another (a status known as mahram) through the act of breastfeeding. One important consequence is that the wet nurse and her family are forbidden to marry the baby and members of the baby's family (e.g. the nursling's biological brother with the milk-mother's biological daughter). Conversely, the milk-relationship allows usually forbidden familiarities between the two groups, (e.g. if the nursling is male, when he becomes an adult he may view the milk-mother and her close female relatives unveiled or in private, exactly as if he were a relation). Thus, according to some Sahih hadith, nursing an adult male could be used as a workaround to Islamic gender segregation, so that a male may be allowed in proximity to the nursing woman, her sisters and her daughters.
  • 3.4K
  • 14 Nov 2022
Topic Review
Ibrexafungerp
Ibrexafungerp is a first-in-class IV/oral triterpenoid antifungal agent. Similar in mechanism of action to echinocandins, ibrexafungerp inhibits (1→3)-β-D-glucan synthase, a key component of the fungal cell wall, resulting in fungicidal activity against Candida spp. Ibrexafungerp demonstrates broad in vitro activity against Candida spp.,Aspergillus spp., dimorphic fungi Pneumocystis and other emerging yeasts and mold pathogens including azole and echinocandin-resistant isolates. It is currently in late clinical development for treatment and prevention of vulvovaginal candidiasis. Other ongoing trials include treatment of serious fungal infections, including, invasive candidiasis, Candida auris infections, invasive aspergillosis and refractory fungal disease in patients not responding to or who are intolerant to standard of care .
  • 3.4K
  • 17 Mar 2021
Topic Review
Zellige
Zellige (Arabic: [zˈliʑ]; Arabic: الزليج; also zelige or zellij) is mosaic tilework made from individually chiseled geometric tiles set into a plaster base. This form of Islamic art is one of the main characteristics of Moroccan architecture. It consists of geometrically patterned mosaics, used to ornament walls, ceilings, fountains, floors, pools and tables.
  • 3.4K
  • 06 Oct 2022
Topic Review
Ferritin
Ferritin is a universal intracellular protein that stores iron and releases it in a controlled fashion. The protein is produced by almost all living organisms, including archaea, bacteria, algae, higher plants, and animals. It is the primary intracellular iron-storage protein in both prokaryotes and eukaryotes, keeping iron in a soluble and non-toxic form. In humans, it acts as a buffer against iron deficiency and iron overload. Ferritin is found in most tissues as a cytosolic protein, but small amounts are secreted into the serum where it functions as an iron carrier. Plasma ferritin is also an indirect marker of the total amount of iron stored in the body; hence, serum ferritin is used as a diagnostic test for iron-deficiency anemia. Aggregated ferritin transforms into a toxic form of iron called hemosiderin. Ferritin is a globular protein complex consisting of 24 protein subunits forming a hollow nanocage with multiple metal–protein interactions. Ferritin that is not combined with iron is called apoferritin.
  • 3.4K
  • 14 Oct 2022
Topic Review
FAO Country Profiles
The FAO Country Profiles are a multilingual web portal which repackages the Food and Agriculture Organization of the United Nations (FAO) information archive on its global activities in agriculture and food security in a single area and catalogues it exclusively by country and thematic areas. The organization aims to offer decision-makers, researchers and project formulators around the world a fast and reliable way to access country-specific information on national food security situations without the need to search individual databases and systems. It aids FAO's database by providing a simple interface containing interactive maps and charts.
  • 3.4K
  • 09 Nov 2022
Topic Review
Mac Transition to Apple Silicon
The Mac transition to Apple Silicon is the planned two-year process of introducing ARM64-based Apple silicon to, and deprecating Intel's x86-64 from, Apple's Macintosh line of computers. CEO Tim Cook announced the plan in his WWDC keynote address on June 22, 2020. The transition is the third time Apple has migrated Macintosh to a new instruction set architecture (ISA). The first was the switch from the Mac's original Motorola 68000 series architecture to the new PowerPC platform in 1994, and the second was the transition from PowerPC to Intel x86, which was formally announced in June 2005. Apple first utilized the ARM architecture in 1993 in its Newton personal digital assistant, and since then has extensively deployed it throughout other product lines including iPhone, iPad, iPod, and Apple Watch. Apple has designed its own custom ARM chips since 2009.
  • 3.4K
  • 02 Nov 2022
Topic Review
End-of-Life Vehicle Management Systems in Southeast Aisa
End-of-life vehicle (ELV) management is becoming increasingly important as the automotive industry is one of the world’s most critical sectors and is rapidly expanding. ELV management is essential for environmental protection and wellbeing under Sustainable Development Goal (SDG) 3, provides more jobs under SDG 8, and promotes a circular economy under SDG 11. All these factors contribute to the importance of ELV management as a research topic. ELV management is well-positioned and an emerging research area particularly on ELV recycling systems in Europe, Japan, Korea, Taiwan and China. Immature ELV management systems in Malaysia, Thailand and Indonesia are the reason that no specific ELV laws and regulations exist, as well as why there are no precise ELV statistics. Nevertheless, there have been growing concerns about ELV management, as evidenced by environmental regulations and programs aimed at better management of ELV recycling in these countries.
  • 3.4K
  • 21 Nov 2022
Topic Review
Biomass Wastes Produce Carbon Dots
The fluorescent carbon dot is a novel type of carbon nanomaterial. In comparison with semiconductor quantum dots and fluorescence organic agents, it possesses significant advantages such as excellent photostability and biocompatibility, low cytotoxicity and easy surface functionalization, which endow it a wide application prospect in fields of bioimaging, chemical sensing, environmental monitoring, disease diagnosis and photocatalysis as well. Biomass waste is a good choice for the production of carbon dots owing to its abundance, wide availability, eco-friendly nature and a source of low cost renewable raw materials such as cellulose, hemicellulose, lignin, carbohydrates and proteins, etc.
  • 3.4K
  • 18 Feb 2021
Topic Review
Bhikkhu
A bhikkhu (Pali: भिक्खु Sanskrit: भिक्षु , bhikṣu) is an ordained male monastic ("monk") in Buddhism. Male and female monastics ("nun", bhikkhunī, Sanskrit bhikṣuṇī) are members of the Buddhist community. The lives of all Buddhist monastics are governed by a set of rules called the prātimokṣa or pātimokkha. Their lifestyles are shaped to support their spiritual practice: to live a simple and meditative life and attain nirvana. A person under the age of 20 cannot be ordained as a bhikkhu or bhikkhuni but can be ordained as a śrāmaṇera or śrāmaṇērī.
  • 3.4K
  • 31 Oct 2022
Topic Review
Time Geography
Time geography or time-space geography is an evolving transdisciplinary perspective on spatial and temporal processes and events such as social interaction, ecological interaction, social and environmental change, and biographies of individuals. Time geography "is not a subject area per se", but rather an integrative ontological framework and visual language in which space and time are basic dimensions of analysis of dynamic processes. Time geography was originally developed by human geographers, but today it is applied in multiple fields related to transportation, regional planning, geography, anthropology, time-use research, ecology, environmental science, and public health. According to Swedish geographer Bo Lenntorp: "It is a basic approach, and every researcher can connect it to theoretical considerations in her or his own way."
  • 3.4K
  • 13 Nov 2022
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