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Topic Review
Datasets in the Field of Click Fraud Detection
Researchers go over the most relevant datasets to detect and prevent ad click fraud using AI techniques. Private/non-open-source datasets, as well as those related to other fraud types, such as ad or impression fraud, are excluded. 
  • 4.5K
  • 13 Feb 2023
Topic Review
GaN(0001) Surfaces
Herein, the surface properties of gallium nitride (GaN) of the wurtzite form, (0001) oriented are presented. X-ray and UV photoelectron spectroscopies (XPS, UPS) were employed to show chemical and physical characters of the surface . Basic information about electronic structure of various doped GaN(0001) surfaces as well as surface Fermi level pinning are discussed.
  • 4.5K
  • 10 Feb 2021
Topic Review
The Biological Effects of Retinoids in the Skin
In the early 20th century, retinol (commonly known as vitamin A) was isolated and characterized as an essential nutrient for human health. Retinoids are natural and synthetic vitamin A derivatives that are effective for the prevention and the treatment of non-melanoma skin cancers. The effects of retinoid signaling on skin physiology have been studied extensively.
  • 4.5K
  • 01 Nov 2022
Topic Review
Postbiological Evolution
Postbiological evolution is a form of evolution which has transitioned from a biological paradigm, driven by the propagation of genes, to a nonbiological (e.g., cultural or technological) paradigm, presumably driven by some alternative replicator (e.g., memes or temes), and potentially resulting in the extinction, obsolescence, or trophic reorganization of the former. Researchers anticipating a postbiological universe tend to describe this transition as marked by the maturation and potential convergence of high technologies, such as artificial intelligence or nanotechnology.
  • 4.5K
  • 25 Nov 2022
Topic Review
DNA Repair Pathways in Folate Deficiency and NTDs
DNA repair pathways are essential for ensuring normal DNA synthesis, genomic stability, and integrity, which are required for a multitude of cellular processes such as cell proliferation, differentiation, cell cycle, apoptosis, and the development of tissues and organs. Defects or inappropriateness in DNA repair pathways are associated with detrimental health effects, including birth defects, cancer, and neurodegenerative diseases. DNA repair genes are over-expressed at the early stages of normal embryonic development in order to reduce possible replication errors and genotoxic damage. The occurrence of NTDs may be related to the abnormality or deletion of various DNA repair pathways. Due to the link between folate deficiency and NER not being particularly evident, the progress of DNA repair pathways (BER, MMR, DSBR) and NTDs with folate deficiency was reviewed here.
  • 4.5K
  • 16 Mar 2023
Topic Review
Synechocystis sp.: A Model Microorganism
Synechocystis sp. is a unicellular, spherical, non-nitrogen-fixing cyanobacterium with 0.7–8 µm in diameter and no or fine and colorless mucilage layer . The cell envelop of Synechocystis sp. contains the outer membrane, a peptidoglycan layer, and cytoplasmic membrane. The thylakoid membranes, derived from the cytoplasmic membrane, cover the peripheral region of the cell . From cyanobacteria to higher plants, thylakoid membranes are the site of photosynthesis converged near the cytoplasmic membrane. Thylakoid centers, fibrous coated cylindrical structures, 40–50 nm in diameter and 50–1000 nm in length, establish and maintain thylakoid membrane organization
  • 4.5K
  • 15 Apr 2022
Topic Review
Xylitol’s Benefits to Skin
Xylitol has been widely documented to have dental health benefits, such as reducing the risk for dental caries. In skin, xylitol has been reported to improve barrier function and suppress the growth of potential skin pathogens. 
  • 4.5K
  • 06 Oct 2021
Topic Review
Nonparametric Limits of Agreement
The assessment of agreement in method comparison and observer variability analysis of quantitative measurements is usually done by the Bland-Altman Limits of Agreement, where the paired differences are implicitly assumed to follow a normal distribution. Whenever this assumption does not hold, the 2.5% and 97.5% percentiles are obtained by quantile estimation. In the literature, empirical quantiles have been used for this purpose. In this simulation study, we applied both sample, subsampling, and kernel quantile estimators as well as other methods for quantile estimation to sample sizes between 30 and 150 and different distributions of the paired differences. The performance of 15 estimators in generating prediction intervals was measured by their respective coverage probability for one newly generated observation. Our results indicated that sample quantile estimators based on one or two order statistics outperformed all the other estimators and can be used for deriving nonparametric Limits of Agreement. For sample sizes exceeding 80 observations, more advanced quantile estimators, such as the Harrell-Davis and estimators of Sfakianakis-Verginis type, which use all the observed differences, performed likewise well, but may be considered intuitively more appealing than simple sample quantile estimators that are based on only two observations per quantile.
  • 4.5K
  • 27 Oct 2020
Topic Review
Power
In physics, power is the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt, equal to one joule per second. In older works, power is sometimes called activity. Power is a scalar quantity. Power is related to other quantities; for example, the power involved in moving a ground vehicle is the product of the traction force on the wheels and the velocity of the vehicle. The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. Likewise, the power dissipated in an electrical element of a circuit is the product of the current flowing through the element and of the voltage across the element.
  • 4.5K
  • 31 Oct 2022
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.
  • 4.5K
  • 12 Jul 2021
Topic Review
Big-Box Store
A big-box store (also supercenter, superstore, or megastore) is a physically large retail establishment, usually part of a chain of stores. The term sometimes also refers, by extension, to the company that operates the store. The store may sell general dry goods, in which case it is a department store, or may be limited to a particular specialty (such establishments are often called "category killers") or may also sell groceries, in which case some countries (mostly in Europe) use the term hypermarket. Typical architectural characteristics include the following: Commercially, big-box stores can be broken down into two categories: general merchandise (examples include Walmart, Kmart and Target), and specialty stores (such as Home Depot, Barnes & Noble, or Best Buy) which specialize in goods within a specific range, such as hardware, books, or consumer electronics respectively. In the late 20th and early 21st centuries, many traditional retailers—such as Tesco and Praktiker opened stores in the big-box-store format in an effort to compete with big-box chains, which are expanding internationally as their home markets reach maturity.
  • 4.5K
  • 26 Oct 2022
Topic Review
Access Economy
The access economy is a business model where goods and services are traded on the basis of access rather than ownership: it refers to renting things temporarily rather than selling them permanently. The term arose as a correction to the term sharing economy because major players in the sharing economy, such as Airbnb, Zipcar, and Uber, are commercial enterprises whose businesses do not involve any sharing. This model uses a technology platform, often accessed via mobile phone, to connect suppliers willing to rent assets (e.g., apartments for rent or cars for transportation services) with consumers. This movement was worth around $26 billion a year in 2015. The number of persons involved in the access economy is not easily measured. The "access economy" or "on-demand economy" poses regulatory and political challenges, such as: defining the nature of the employment relationship; designing regulations to safeguard parties to these transactions; the loss of taxes and corporate access that results from moving away from small locally owned companies to large remote technology companies; and the bypassing of local regulations (such as the requirement for taxi drivers to provide wheelchair vans, or provide drivers 24-7).
  • 4.5K
  • 04 Nov 2022
Topic Review
Tetraspanins of extracellular vesicles
Tetraspanins are transmembrane proteins with ability to interact with each other and with other non-tetraspanin partners, building up a complex called tetraspanin web. This dynamic structure participates in many cellular processes. Although currently, the tetraspanin proteins found in extracellular vesicles are mostly applied as markers, increasing evidence points to their role in extracellular vesicle biogenesis, cargo selection, cell targeting, and cell uptake under both physiological and pathological conditions.
  • 4.5K
  • 02 Nov 2020
Topic Review
Flow-Induced Vibration
Flow-induced vibration (FIV) of bluff body structures is a classical bidirectional flow–structure interaction problem, which is linked to various fluid dynamics phenomena (e.g., boundary-layer separation, vortex formation and shedding, hydrodynamic loading on the structures) as well as structure vibrations.
  • 4.5K
  • 01 Dec 2022
Topic Review
Biocontrol Agents
Biocontrol agents (BCAs) are living organisms and their derivatives that act against plant diseases and pests via direct antagonistic effects but also indirectly via the induction of plant resistance. They have been proposed as an alternative to standard fungicides but their disease management capacity is usually incomplete and heavily relies on uncontrollable environmental conditions. An integrated approach of combining BCAs with fungicides can reduce the fungicide doses to manage plant diseases and thereby their residual effects that affect the environment and human health.
  • 4.5K
  • 16 Dec 2020
Topic Review
Properties of Seashells
Researchers around the world have conducted extensive experiments with waste seashells in the form of seashell aggregates and seashell powder. The physical, mechanical, and durability properties of seashell concrete are largely determined by the properties of the aggregates and powders that make up the shell.
  • 4.5K
  • 21 Mar 2024
Topic Review
List of Intel Celeron Microprocessors
The Celeron is a family of microprocessors from Intel targeted at the low-end consumer market. CPUs in the Celeron brand have used designs from sixth- to eighth-generation CPU microarchitectures.
  • 4.5K
  • 06 Dec 2022
Topic Review
Charivari
Charivari, shivaree, chivaree, or skimmington (ride) was a folk custom in which a mock parade was staged through a community accompanied by a discordant mock serenade. Since the crowd aimed to make as much noise as possible by beating on pots and pans or anything that came to hand these parades are often referred to as rough music. Parades were of three types. In the first, and generally most violent form, a wrongdoer or wrongdoers might be dragged from their home or place of work and paraded by force through a community. In the process they were subject to the derision of the crowd, they might be pelted and frequently a victim or victims were dunked at the end of the proceedings. A safer form involved a neighbour of the wrongdoer impersonating the victim whilst being carried through the streets. The impersonator was obviously not himself punished and he often cried out or sang ribald verses mocking the wrongdoer. In the common form, an effigy was employed instead, abused and often burnt at the end of the proceedings. Communities used "rough music" to express their disapproval of different types of violation of community norms. For example, they might target marriages of which they disapproved such as a union between an older widower and much younger woman, or the too early remarriage by a widow or widower. Villages also used charivari in cases of adulterous relationships, against wife beaters, and unmarried mothers. It was also used as a form of shaming upon husbands who were beaten by their wives and had not stood up for themselves. In some cases, the community disapproved of any remarriage by older widows or widowers. Charivari is the original French word, and in Canada it is used by both English and French speakers. Chivaree became the common variant in Ontario, Canada. In the United States, the term shivaree is more common. As species of popular justice rituals Charivaric events were carefully planned and they were often staged at times of traditional festivity thereby blending delivering justice and celebration.
  • 4.5K
  • 17 Oct 2022
Topic Review
Sadhu
A sadhu (IAST: sādhu (male), sādhvī or sādhvīne (female)), also spelled saddhu, is a religious ascetic, mendicant (monk) or any holy person in Hinduism and Jainism who has renounced the worldly life. They are sometimes alternatively referred to as jogi, sannyasi or vairagi. It literally means one who practises a ″sadhana″ or keenly follows a path of spiritual discipline. Although the vast majority of sādhus are yogīs, not all yogīs are sādhus. The sādhu is solely dedicated to achieving mokṣa (liberation), the fourth and final aśrama (stage of life), through meditation and contemplation of Brahman. Sādhus often wear simple clothing, such saffron-coloured clothing in Hinduism, white or nothing in Jainism, symbolising their sannyāsa (renunciation of worldly possessions). A female mendicant in Hinduism and Jainism is often called a sadhvi, or in some texts as aryika.
  • 4.5K
  • 10 Nov 2022
Topic Review
Backbone Chain
In polymer science, the backbone chain of a polymer is the longest series of covalently bonded atoms that together create the continuous chain of the molecule. This science is subdivided into the study of organic polymers, which consist of a carbon backbone, and inorganic polymers which have backbones containing only main group elements. In biochemistry, organic backbone chains make up the primary structure of macromolecules. The backbones of these biological macromolecules consist of central chains of covalently bonded atoms. The characteristics and order of the monomer residues in the backbone make a map for the complex structure of biological polymers (see Biomolecular structure). The backbone is, therefore, directly related to biological molecules’ function. The macromolecules within the body can be divided into four main subcategories, each of which are involved in very different and important biological processes: proteins, carbohydrates, lipids, and nucleic acids. Each of these molecules has a different backbone and consists of different monomers each with distinctive residues and functionalities. This is the driving factor of their different structures and functions in the body. Although lipids have a "backbone," they are not true biological polymers as their backbone is a three carbon molecule, glycerol, with longer substituent "side chains." For this reason, only proteins, carbohydrates, and nucleic acids should be considered as biological macromolecules with polymeric backbones.
  • 4.5K
  • 21 Nov 2022
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