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Topic Review
Newgrounds
Newgrounds (collectively Newgrounds.com, Inc.) is an American online entertainment and social media website and company. It hosts user-generated content such as gaming, filming, audio and artwork composition in four respective website categories. While AOL and Geocities had statically hosted user-generated content, Newgrounds provided visitor-driven voting and ranking of user-generated animations. The site's founder and owner, Thomas "Tom" Fulp, founded the site and company in 1995 and produces in-house content over at the headquarters and offices, based in the Glenside neighborhood of Cheltenham Township, Pennsylvania.
  • 4.1K
  • 19 Oct 2022
Topic Review
Tree of Life
The tree of life or universal tree of life is a metaphor, model and research tool used to explore the evolution of life and describe the relationships between organisms, both living and extinct, as described in a famous passage in Charles Darwin's On the Origin of Species (1859). {{Blockquote Tree diagrams originated in the medieval era to represent genealogical relationships. Phylogenetic tree diagrams in the evolutionary sense date back to the mid-nineteenth century. The term phylogeny for the evolutionary relationships of species through time was coined by Ernst Haeckel, who went further than Darwin in proposing phylogenic histories of life. In contemporary usage, tree of life refers to the compilation of comprehensive phylogenetic databases rooted at the last universal common ancestor of life on Earth. Two public databases for the tree of life are TimeTree, for phylogeny and divergence times, and the Open Tree of Life, for phylogeny.
  • 4.1K
  • 18 Oct 2022
Topic Review
Physical Activity Patterns
Although “physical activity pattern” (PAP) is a widely used expression, its precise meaning remains vague. Indeed, PAP is sometimes used to describe physical activity (PA) levels/intensities, however the term is also applied to express how PA averages differ among group,  between different days (i.e., week and weekend days), across seasons (e.g., summer, winter), and between school and vacation time. A lack of a formal definition for PAP has not prevented researchers from using a vast array of instruments to measure PA (accelerometers, pedometers, questionnaires, direct observations, and heart rate monitors) in an attempt to capture PAP. Discrepancies also exist in how PAP has been expressed with researchers using daily mean PA, heart rate frequency, number of daily steps, time engaged in certain types of activity, and/or engagement in sports activities. Researchers have also used numerous statistical procedures in their attempts to capture PAP. Notwithstanding this diversity, we suggest that PAP should be used to jointly capture similarities/dissimilarities as well as stabilities/changes in children’s PA at an intra-personal level. PAP should be used to best describe individual streams of behaviours, and not exclusively PA levels/intensities. A formal and clear definition of PAP would support important, systematic, and coherent lines of empirical enquiry.
  • 4.1K
  • 24 Apr 2021
Topic Review
Carbohydrates, Deep and REM Sleep
Carbohydrate quantity was shown to affect sleep architecture, and especially N3 and REM sleep stages. Alterations in both quantity and quality of carbohydrate intake showed a significant effect on sleep initiation. Variations in carbohydrate quality significantly affected measures of sleep continuation. Further studies are needed to assess the effect of long-term carbohydrate interventions on sleep. 
  • 4.1K
  • 28 Sep 2021
Topic Review
Economy Car
An economy car is an automobile that is designed for low-cost purchase and operation. Typical economy cars are small (compact or subcompact), lightweight, and inexpensive to buy. Economy car designers are forced by stringent design constraints to be inventive. Many innovations in automobile design were originally developed for economy cars, such as the Ford Model T and the Austin Mini. The alternative approach, other than innovating to build a low-cost car, is to build a stripped-down, no-frills version of a conventional car. Gordon Murray, the Formula 1 and McLaren F1 designer, said when designing his new Murray T.25 city car: "I would say that building a car to sell for six thousand pounds and designing that for a high-volume production, where you have all the quality issues under control, is a hundred times more difficult than designing a McLaren F1, or even a racing car. It is certainly the biggest challenge I've ever had from a design point of view."
  • 4.1K
  • 17 Oct 2022
Topic Review
High Performance Liquid Chromatography with Fluorescence Detection Methods
Steroids are compounds widely available in nature and synthesized for therapeutic and medical purposes. Although several analytical techniques are available for the quantification of steroids, their analysis is challenging due to their low levels and complex matrices of the samples. The efficiency and quick separation of the high performance liquid chromatography (HPLC) combined with the sensitivity, selectivity, simplicity, and cost-efficiency of fluorescence, make HPLC coupled to fluorescence detection (HPLC-FLD) an ideal tool for routine measurement and detection of steroids.
  • 4.1K
  • 01 Aug 2022
Topic Review
Purple Tomatoes
Purple tomatoes represent a recent variant of tomato fruits characterized by a purple coloration, not present in the more common red fruited varieties. This peculiar pigmentation is due to the presence of anthocyanins. These are plant secondary metabolites responsible for red, purple and blue colorations of flowers, fruits and leaves in many species. They are usually assumed with the diet, being rich sources mostly represented by red and purple fruits or dark vegetables (e.g., berries, cherries, plums, grapes, black beans, red onions, eggplant, red cabbage, purple sweet potatoes). As other polyphenolic compounds, they can provide many health benefits, and, as a consequence, their consumption can be helpful in reducing the incidence of cardiovascular, metabolic and degenerative or chronic diseases and of certain types of cancer. Tomato fruits are naturally rich of carotenoids, vitamins and polyphenols, but do not contain anthocyanins, due to mutations in their specific biosynthetic pathway. However, in recent years, either through genetic engineering or introgression by breeding of specific gene variants using wild relatives, this biosynthetic block has been overcome. This allowed the production of the new tomatoes’ phenotypes characterized by purple pigmentation localized only on the fruit peel or in both peel and flesh. In purple tomatoes, the high concentrations of anthocyanins that can be achieved, and not to the detriment of other metabolites, represent a real added nutritional value of these fruits.
  • 4.1K
  • 15 Jan 2021
Topic Review
Step-Down Partial Power DC-DC Converters
Photovoltaic (PV) systems made-up by two-stages of energy conversion are attractive from the operation point view. It is because the MPPT range is extended, due to the voltage decoupling between the PV system and the dc-link. Nevertheless, the additional conversion stage increases the volume, cost and power converter losses. Therefore, in large-scale PV systems formed by series connection of PV modules, most of commercial inverters are based on a single-stage system. The concept of partial power converters (PPC), previously implemented as a step-up stage, has not fully covered all PV applications. In this work, a PPC performing step-down operation is proposed and analyzed for a PV string application. This concept is actually interesting from the industry point of view, since with the new isolation standards of PV modules reaching 1500V, larger strings are currently starting to become popular. Since grid connection remains below 690V, larger strings impose more demanding operation for single-stage central inverters (required to operate at lower modulation indexes and demand higher blocking voltage devices). 
  • 4.1K
  • 01 Nov 2020
Topic Review
Translation
In molecular biology and genetics, translation is the process in which ribosomes in the cytoplasm or endoplasmic reticulum synthesize proteins after the process of transcription of DNA to RNA in the cell's nucleus. The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain, or polypeptide. The polypeptide later folds into an active protein and performs its functions in the cell. The ribosome facilitates decoding by inducing the binding of complementary tRNA anticodon sequences to mRNA codons. The tRNAs carry specific amino acids that are chained together into a polypeptide as the mRNA passes through and is "read" by the ribosome. Translation proceeds in three phases: In prokaryotes (bacteria and archaea), translation occurs in the cytosol, where the large and small subunits of the ribosome bind to the mRNA. In eukaryotes, translation occurs in the cytoplasm or across the membrane of the endoplasmic reticulum in a process called co-translational translocation. In co-translational translocation, the entire ribosome/mRNA complex binds to the outer membrane of the rough endoplasmic reticulum (ER) and the new protein is synthesized and released into the ER; the newly created polypeptide can be stored inside the ER for future vesicle transport and secretion outside the cell, or immediately secreted. Many types of transcribed RNA, such as transfer RNA, ribosomal RNA, and small nuclear RNA, do not undergo translation into proteins. A number of antibiotics act by inhibiting translation. These include anisomycin, cycloheximide, chloramphenicol, tetracycline, streptomycin, erythromycin, and puromycin. Prokaryotic ribosomes have a different structure from that of eukaryotic ribosomes, and thus antibiotics can specifically target bacterial infections without any harm to a eukaryotic host's cells.
  • 4.1K
  • 14 Nov 2022
Topic Review
The Transactional Distance Theory and Distance Learning Contexts
Moore established transactional distance theory (TDT) to grasp transactional distance in the context of distance learning. Research using TDT in distance, open, and online learning environments has been undertaken. However, there are information gaps about what constitutes progress, future directions, and research deficits pertaining to TDT in the context of distance education. TDT research in distance learning integrates various theories and models; nevertheless, there is a movement toward acceptance models and how to incorporate more relevant theories within the framework of distance learning. Future studies should integrate other aspects such as student motivation, student acceptance of technology, and student preparedness and desire to utilize technology in learning environments. As most research samples students, a research gap involving instructors and heterogeneous groups is proposed. It is projected that quantitative research will predominate in the future, leaving qualitative and mixed approaches as areas of investigation. 
  • 4.1K
  • 10 Feb 2023
Topic Review
The Luminous Fungi of Japan
Luminous fungi have long attracted public attention in Japan, from old folklore and fiction to current tourism, children’s toys, games, and picture books. 25 species of luminous fungi have been discovered in Japan, which correspond to approximately one-fourth of the globally recognized species. This species richness is arguably due to the abundant presence of mycophiles looking to find new mushroom species and a tradition of night-time activities, such as firefly watching, in Japan.
  • 4.1K
  • 31 May 2023
Topic Review
Wearable Stretch Sensors
Wearable sensors are beneficial for continuous health monitoring, movement analysis, rehabilitation, evaluation of human performance. Wearable stretch sensors are increasingly being used for human movement monitoring. The content presented provides a review of wearable stretch sensors as well the design, development and validation of a wearable soft-robotic-stretch sensors. 
  • 4.1K
  • 25 Feb 2021
Topic Review
Phenolic Compounds and Its Linkage
Medicinal plants, along with cereals, fruits, herbs, and vegetables, are the main sources of phenolic compounds, of which nearly 10,000 have been reported in nature to date. They are secondary metabolites produced by plants to protect them from abiotic factors (e.g., drought, extreme temperatures, floods, heavy metals, pH, radiation, salinity, and soils) and biotic factors, such as animals and pathogens attack.
  • 4.1K
  • 29 Apr 2022
Topic Review
Phospholipids
Phospholipids are unique and versatile molecules. They are of natural occurrence and the main components in cellular membranes. Arranged as a lipid bilayer, phospholipids play a significant role in the structure and functionality of biological membranes. They are amphiphilic and consist of a hydrophilic headgroup and a lipophilic/hydrophobic tail.
  • 4.1K
  • 04 Feb 2021
Topic Review
Social Stratification
Social stratification is the hierarchical arrangement of individuals or groups in a society based on various attributes such as wealth, social status, and power. This system categorizes people into different strata, influencing their access to resources, opportunities, and privileges. Social stratification is a pervasive phenomenon that shapes social interactions and plays a crucial role in determining an individual's life chances and societal positioning.
  • 4.1K
  • 25 Jan 2024
Topic Review
Earwax
Earwax, also known by the medical term cerumen, is a brown, orange, red, yellowish or gray waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, and provides protection against bacteria, fungi, and water. Earwax consists of dead skin cells, hair, and the secretions of cerumen by the ceruminous and sebaceous glands of the outer ear canal. Major components of earwax are long chain fatty acids, both saturated and unsaturated, alcohols, squalene, and cholesterol. Excess or compacted cerumen is the buildup of ear wax causing a blockage in the ear canal and it can press against the eardrum or block the outside ear canal or hearing aids, potentially causing hearing loss.
  • 4.1K
  • 07 Nov 2022
Topic Review
Antibacterial Designs for Implantable Medical Devices
The uses of implantable medical devices are safer and more common since sterilization methods and techniques were established a century ago; however, device-associated infections (DAIs) are still frequent and becoming a leading complication as the number of medical device implantations keeps increasing.
  • 4.1K
  • 01 Aug 2022
Topic Review
Ketamine and Driving, Cognitive, and Motor Ability
Ketamine is a medication that has many medical purposes but also has been used illicitly by people for its dissociative properties. While driving under the influence of drugs, drivers are more likely to be involved in and cause more accidents than drivers who do not drive under the influence.  A study with ketamine and a ketamine-like medication, rapasitnel, showed that those who were given ketamine experienced more sleepiness and had decreased self-reported motivation and confidence in their driving abilities. Moreover, there seem to be significant differences in the acute versus persistent effects of ketamine, as well as the anesthetic versus subanesthetic doses, both in terms of effects and outcomes. These divergent effects complicate the clinical uses of ketamine, specifically involving driving, drowsiness, and cognitive abilities. 
  • 4.1K
  • 16 Mar 2023
Topic Review
Three-Dimensional Printing of Living Mycelium-Based Composites
The construction industry makes a significant contribution to global CO2 emissions. Material extraction, processing, and demolition account for most of its environmental impact. As a response, there is an increasing interest in developing and implementing innovative biomaterials that support a circular economy, such as mycelium-based composites. The mycelium is the network of hyphae of fungi. Mycelium-based composites are renewable and biodegradable biomaterials obtained by ceasing mycelial growth on organic substrates, including agricultural waste.
  • 4.1K
  • 04 Sep 2023
Topic Review
Zone Refining
Zone refining is a technology of deeply purifying metals. Its essence is to use the difference in solubility of impurity elements in the solid and molten state of the main metal to precipitate the impurities or change the distribution of the impurity elements. It provides an effective and easy method for preparing high-purity metals. 
  • 4.1K
  • 18 May 2021
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