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Topic Review
Ceramic Materials for Biomedical Applications
The word “biomaterial” refers to a substance or a mix of materials of synthetic or natural origin interacting with biological systems. The main purpose of biomaterials is to support the healing or replacement of an organ in a human body that has been altered by a disease or an accidental event and to successfully restore function and sometimes aesthetic features without endangering human life. Biomaterials can be classified according to their chemical nature as metallic, polymeric, ceramic, and composite, and can also be biologically derived. The term “ceramic” (from the Greek word κεραμικό: “keramikò,” which means “burnt stuff”), a word that is also found in ancient texts, indicates any heat-treated material derived from clayey raw materials through a process called firing. Generally speaking, ceramics are inorganic materials consisting of metallic and non-metallic components chemically bonded together by means of ionic or prevalently ionic bonds with a variable degree of covalent character. 
  • 4.4K
  • 07 Apr 2023
Topic Review
Runx2 and Osteoblasts
Runx2 is essential for osteoblast differentiation, chondrocyte maturation, and transdifferentiation of terminally differentiated chondrocytes into osteoblasts. During osteoblast differentiation, Runx2 is weakly expressed in uncommitted mesenchymal cells, and its expression is upregulated in preosteoblasts, reaches the maximal level in immature osteoblasts, and is down-regulated in mature osteoblasts. Runx2 enhances the proliferation of osteoblast progenitors by directly regulating Fgfr2 and Fgfr3. Runx2 enhances the proliferation of suture mesenchymal cells and induces their commitment into osteoblast lineage cells through the direct regulation of hedgehog (Ihh, Gli1, and Ptch1), Fgf (Fgfr2 and Fgfr3), Wnt (Tcf7, Wnt10b, and Wnt1), and Pthlh (Pthr1) signaling pathway genes, and Dlx5. Runx2 heterozygous mutation causes open fontanelle and sutures because more than half of the Runx2 gene dosage is required for the induction of these genes in suture mesenchymal cells. Runx2 induces the proliferation of osteoblast progenitors and their differentiation into osteoblasts through reciprocal regulation via major signaling pathways, including Fgf, hedgehog, Wnt, and Pthlh, and transcription factors, including Sp7 and Dlx5. Runx2 also regulates the expression of bone matrix protein genes, including Col1a1, Col1a2, Spp1, and Bglap/Bglap2. Bglap/Bglap2 (osteocalcin) aligns biological apatite parallel to the collagen fibrils, which is important for bone strength, but osteocalcin does not play a role as a hormone in the pancreas, testis, and muscle. 
  • 4.4K
  • 22 Apr 2021
Topic Review
Mercury's Magnetic Field
Mercury's magnetic field is approximately a magnetic dipole (meaning the field has only two magnetic poles) apparently global, on planet Mercury. Data from Mariner 10 led to its discovery in 1974; the spacecraft measured the field's strength as 1.1% that of Earth's magnetic field. The origin of the magnetic field can be explained by dynamo theory. The magnetic field is strong enough near the bow shock to slow the solar wind, which induces a magnetosphere.
  • 4.4K
  • 15 Nov 2022
Topic Review
Herbalism
Herbalism (also herbal medicine) is the study of botany and use of plants intended for medicinal purposes. Plants have been the basis for medical treatments through much of human history, and such traditional medicine is still widely practiced today. Modern medicine makes use of many plant-derived compounds as the basis for evidence-based pharmaceutical drugs. Although phytotherapy may apply modern standards of effectiveness testing to herbs and medicines derived from natural sources, few high-quality clinical trials and standards for purity or dosage exist. The scope of herbal medicine is sometimes extended to include fungal and bee products, as well as minerals, shells and certain animal parts. The term, phytomedicine, may also refer to the science of pathology and damage to plants, the causes thereof, their manifestations, development, dissemination, methods for maintaining plant health, and measures used to control plant diseases and their causes. Herbal medicine is sometimes also used to refer to paraherbalism or phytotherapy, which is the alternative and pseudoscientific practice of using of extracts of plant or animal origin as supposed medicines or health-promoting agents. Phytotherapy differs from plant-derived medicines in standard pharmacology because it does not isolate and standardize the compounds from a given plant believed to be biologically active. It relies on the false belief that preserving the complexity of substances from a given plant with less processing is safer and potentially more effective. There is no evidence that either condition applies. Herbal dietary supplements most often fall under this category.
  • 4.4K
  • 11 Oct 2022
Topic Review
A Certain Magical Index
A Certain Magical Index (Japanese: とある魔術の禁書目録 (インデックス), Hepburn: Toaru Majutsu no Indekkusu)[lower-alpha 1] is a Japanese light novel series written by Kazuma Kamachi and illustrated by Kiyotaka Haimura, which has been published by ASCII Media Works under their Dengeki Bunko imprint since April 2004. The plot is set in a world where supernatural abilities exist. The light novels focus on Toma Kamijo, a young high school student in Academy City who has an unusual ability, as he encounters an English nun named Index. His ability and relationship with Index proves dangerous to other sorcerers and Espers who want to discover the secrets behind him and Index, as well as the city. Yen Press have licensed the novels in North America. A manga adaptation by Chuya Kogino began serialization in Monthly Shōnen Gangan from May 2007. J.C.Staff produced two 24-episode anime series between 2008 and 2011. An animated film was released in February 2013. The anime adaptations are licensed in North America by Funimation. A 26-episode third season aired between 2018 and 2019, licensed by Funimation. The side-story manga series, A Certain Scientific Railgun, began serialization in Dengeki Daioh in February 2007. A second side-story manga series, A Certain Scientific Accelerator, began serialization in Dengeki Daioh in December 2013.
  • 4.4K
  • 19 Oct 2022
Topic Review
Anatomy of the Rumen Affecting the Microbiome
The rumen is a complex organ that is critical for its host to convert low-quality feedstuffs into energy. The conversion of lignocellulosic biomass to volatile fatty acids and other end products is primarily driven by the rumen microbiome and its interaction with the host. Importantly, the rumen is demarcated into five distinct rumen sacs as a result of anatomical structure, resulting in variable physiology among the sacs. 
  • 4.4K
  • 23 Mar 2023
Topic Review Peer Reviewed
Wooden Additional Floor in Finland
One of the most effective ways to cover real estate development and renovation processes by improving functionality and energy efficiency is wooden additional floor construction. The scattered information is mapped out, organized, and collated on the current state of the art and the benefits of this practice including its different stages, focusing on the case of Finland. The topic is presented in an accessible and understandable discourse for non-technical readers. By highlighting the benefits and opportunities of this sustainable application, it will contribute to increasing the awareness of wooden additional floor construction, which has many advantages, and therefore to gain more widespread use in Finland and other countries.
  • 4.4K
  • 14 Apr 2022
Topic Review
Certis CISCO
Coordinates: 1°19′16.88″N 103°53′30.67″E / 1.3213556°N 103.8918528°E / 1.3213556; 103.8918528 Certis CISCO Security Private Limited, formerly CISCO Security Private Limited, is one of the five commercial Auxiliary Police forces authorized to provide armed security officers to government organizations as well as private companies or individuals in Singapore. It has its roots as a department of the Singapore Police Force (SPF), which branched out as the Commercial and Industrial Security Corporation, a statutory board with a monopoly over most areas of the local private armed security industry. From 1 June 2005, the statutory board was dissolved and Cisco Security Pte Ltd was formed upon its corporatisation as a fully owned subsidiary of Temasek Holdings, and inaugurated on 5 July 2005. The abbreviation of the former statutory board, "CISCO", was retained due to its reputation in the local market. The company was renamed as Certis CISCO Security Pte Ltd on 13 September 2007. Cisco Annual Security Report on 20 January 2016 reveals a decline in defender confidence and the increased impact of industrialized attackers. As the oldest Auxiliary Police Force with a monopoly over most of the private armed security sector in Singapore for 33 years, CISCO maintains a visible presence in many key establishments, including the private residences of VVIPs. They were deployed in major events such as the Singapore 2006 IMF Meetings, the New Year Countdown at Marina Bay in 2007 and 2008, the Chingay Parade and the Thaipusam processions. They also continue to dominate some services such as the transportation of valuables, most visibly in the form of delivering cash to automated teller machines.
  • 4.4K
  • 08 Nov 2022
Topic Review
Weather Radar
The history of Weather Radar (abbreviation of RAdio Detecting And Ranging) begins during World War II, when military radar operators noticed extraneous echoes showing up on their display. David Atlas was one of the pioneers of radar meteorology, along with John Stewart Marshall, Walter Palmer and Richard Doviak. Weather radars send pulses of electromagnetic energy into the atmosphere, a microsecond of long microwave radiation to identify the presence of hydrometeors.
  • 4.4K
  • 17 Feb 2022
Topic Review
Sustainable Consumer Behavior
Sustainable Consumer Behavior, namely a new sustainable consumer model, refers to major shifts in buying and consumption habits. Nevertheless, these shifts were lagging as consumers resisted change in the comfort of old habits. This comfort was shaken up by the COVID-19 outbreak that forced us to rethink every aspect of our lives. Therefore, this crisis context seems the perfect opportunity to shift towards the sustainable consumer model.
  • 4.4K
  • 09 Jun 2021
Topic Review
Methanol
Methanol, an alcohol with an odor similar to that of ethanol, has been described to exist in low concentrations in the human organism and occurs naturally at a low level in most spirits, without conferring health risk if it exists within the legal limits. 
  • 4.4K
  • 20 Jan 2021
Topic Review
List of Intel Core I7 Microprocessors
The following is a list of Intel Core i7 brand microprocessors. Introduced in 2008, the Core i7 line of microprocessors are intended to be used by high-end users.
  • 4.4K
  • 24 Nov 2022
Biography
Robert Noyce
Robert Norton Noyce (December 12, 1927 – June 3, 1990), nicknamed "the Mayor of Silicon Valley," was an American physicist who co-founded Fairchild Semiconductor in 1957 and Intel Corporation in 1968. He is also credited (along with Jack Kilby) with the realization of the first integrated circuit or microchip that fueled the personal computer revolution and gave Silicon Valley its name.[1][2]
  • 4.4K
  • 08 Dec 2022
Topic Review
Centrifugal Fan
A centrifugal fan is a mechanical device for moving air or other gases in a direction at an angle to the incoming fluid. Centrifugal fans often contain a ducted housing to direct outgoing air in a specific direction or across a heat sink; such a fan is also called a blower, blower fan, biscuit blower, or squirrel-cage fan (because it looks like a hamster wheel). These fans increase the speed and volume of an air stream with the rotating impellers. Centrifugal fans use the kinetic energy of the impellers to increase the volume of the air stream, which in turn moves against the resistance caused by ducts, dampers and other components. Centrifugal fans displace air radially, changing the direction (typically by 90°) of the airflow. They are sturdy, quiet, reliable, and capable of operating over a wide range of conditions. Centrifugal fans are constant-displacement or constant-volume devices, meaning that, at a constant fan speed, a centrifugal fan moves a relatively constant volume of air rather than a constant mass. This means that the air velocity in a system is fixed even though the mass flow rate through the fan is not. Centrifugal fans are not positive-displacement devices and centrifugal fans have certain advantages and disadvantages when contrasted with positive-displacement blowers: centrifugal fans are more efficient, whereas positive-displacement blowers may have a lower capital cost. The centrifugal fan has a drum shape composed of a number of fan blades mounted around a hub. As shown in the animated figure, the hub turns on a driveshaft mounted in bearings in the fan housing. The gas enters from the side of the fan wheel, turns 90 degrees and accelerates due to centrifugal force as it flows over the fan blades and exits the fan housing.
  • 4.4K
  • 23 Oct 2022
Topic Review
Tudor Rose
The Tudor rose (sometimes called the Union rose) is the traditional floral heraldic emblem of England and takes its name and origins from the House of Tudor, which united the House of Lancaster and the House of York. The Tudor rose consists of five white inner petals, representing the House of York, and five red outer petals to represent the House of Lancaster.
  • 4.4K
  • 16 Nov 2022
Topic Review
Plagioclase
Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continuous solid solution series, more properly known as the plagioclase feldspar series. This was first shown by the German mineralogist Johann Friedrich Christian Hessel (1796–1872) in 1826. The series ranges from albite to anorthite endmembers (with respective compositions NaAlSi3O8 to CaAl2Si2O8), where sodium and calcium atoms can substitute for each other in the mineral's crystal lattice structure. Plagioclase in hand samples is often identified by its polysynthetic crystal twinning or 'record-groove' effect. Plagioclase is a major constituent mineral in the Earth's crust, and is consequently an important diagnostic tool in petrology for identifying the composition, origin and evolution of igneous rocks. Plagioclase is also a major constituent of rock in the highlands of the Moon. Analysis of thermal emission spectra from the surface of Mars suggests that plagioclase is the most abundant mineral in the crust of Mars. Its name comes from Ancient Greek plágios (πλάγιος 'oblique') + klásis ((κλάσις 'fracture'), in reference to its two cleavage angles.
  • 4.3K
  • 25 Nov 2022
Topic Review
Polymer-Derived Ceramics
Ceramics derived from organic polymer precursors, which have exceptional mechanical and chemical properties that are stable up to temperatures slightly below 2000 °C, are referred to as polymer-derived ceramics (PDCs).
  • 4.3K
  • 09 Feb 2021
Topic Review
Calcium in Wound Healing
Calcium is a critical coagulation factor during hemostasis and a key signaling molecule for a variety of signaling pathways that regulate angiogenesis. In addition, the calcium ion has also been shown to act as a fundamental cue, directing the cellular functions of different types of cells during wound healing. Calcium plays a vital role as the extracellular signaling molecule and intracellular second messenger for keratinocytes and fibroblasts.
  • 4.3K
  • 12 Jul 2021
Topic Review Peer Reviewed
Benefits of Badminton for Preventing Cognitive Decline and Dementia
Badminton is one of the most popular racket sports played by all age groups worldwide. Anyone can practice and play badminton as a leisure or competitive sport, regardless of age, experience, or skill level. It does not require physical contact among players or expensive equipment. Compared with closed-skill exercises (e.g., running and swimming), open-skill exercises (e.g., badminton and table tennis) have been reported to significantly improve cognitive function and prevent cognitive decline. This mini review aimed to investigate the findings related to badminton intervention for cognitive function, with attention to the modifiable risk factors of dementia in adults. Additionally, we outlined the characteristics of badminton’s physical demands. This narrative review encompassed studies reported from 2013 to 2023 from multiple databases, including PubMed and Google Scholar. Keywords such as “badminton”, “dementia”, “cognitive function”, “physical activity”, and “depression” were used to identify relevant articles. Various studies, including randomized controlled trials, cohort studies, and case–control studies, were selected to provide a comprehensive overview of badminton intervention. Quantitative data analysis suggests that at a cognitive level, high-intensity badminton can enhance cognitive function with at least 10 min of play once weekly or 20 min of play once weekly on average, whereas moderate-intensity badminton can be effective when played for at least 30 min once weekly or 35 min twice weekly on average. For modifiable risk factors, recreational badminton for about 3 h weekly could effectively manage blood pressure. For body fat percentage and fasting serum glucose levels, recreational badminton for about 10 h weekly exerted positive effects. For depressive states, a moderate-intensity badminton program for 100 min weekly was effective. For lipid profiles associated with dementia occurrence, prolonged badminton intervention for more than 3 months may be beneficial. The characteristics presented here indicate that intervention with regular badminton exercise could effectively improve cognitive function and prevent cognitive decline in older adults.
  • 4.3K
  • 18 Jun 2024
Topic Review
Vocabulary Development
Vocabulary development is a process by which people acquire words. Babbling shifts towards meaningful speech as infants grow and produce their first words around the age of one year. In early word learning, infants build their vocabulary slowly. By the age of 18 months, infants can typically produce about 50 words and begin to make word combinations. In order to build their vocabularies, infants must learn about the meanings that words carry. The mapping problem asks how infants correctly learn to attach words to referents. Constraints theories, domain-general views, social-pragmatic accounts, and an emergentist coalition model have been proposed to account for the mapping problem... From an early age, infants use language to communicate. Caregivers and other family members use language to teach children how to act in society. In their interactions with peers, children have the opportunity to learn about unique conversational roles. Through pragmatic directions, adults often offer children cues for understanding the meaning of words. Throughout their school years, children continue to build their vocabulary. In particular, children begin to learn abstract words. Beginning around age 3–5, word learning takes place both in conversation and through reading. Word learning often involves physical context, builds on prior knowledge, takes place in social context, and includes semantic support. The phonological loop and serial order short-term memory may both play an important role in vocabulary development.
  • 4.3K
  • 14 Nov 2022
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