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Topic Review
Deep Learning-based Contactless PPG Methods
Physiological measurements are widely used to determine a person’s health condition. Photoplethysmography (PPG) is a physiological measurement method that is used to detect volumetric changes in blood in vessels beneath the skin. Medical devices based on PPG have been introduced to measure different physiological measurements including heart rate (HR), respiratory rate, heart rate variability (HRV), oxyhemoglobin saturation, and blood pressure. Due to its low cost and non-invasive nature, PPG is utilized in many devices such as finger pulse oximeters, sports bands, and wearable sensors. PPG-based physiological measurements can be categorized into two types: contact-based and contactless.
  • 2.7K
  • 08 Jun 2021
Topic Review
Interleukin-4 and Interleukin-13 Induced Atopic Dermatitis
Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with widespread barrier dysfunction and T helper 2 (Th2) cytokines. AD is an imbalance in the Th2 immune response where there is an increase in the gene expression levels of major Th2 cytokines during the acute phase.
  • 2.7K
  • 07 Mar 2022
Topic Review
Social Networking and Psychology
Social media began in the form of generalized online communities. These online communities formed on websites like Geocities.com in 1994, Theglobe.com in 1995, and Tripod.com in 1995. Many of these early communities focused on social interaction by bringing people together through the use of chat rooms. The chat rooms encouraged users to share personal information, ideas, or even personal web pages. Later the social networking community Classmates took a different approach by simply having people link to each other by using their personal email addresses. By the late 1990s, social networking websites began to develop more advanced features to help users find and manage friends. These newer generation of social networking websites began to flourish with the emergence of SixDegrees.com in 1997, Makeoutclub in 2000, Hub Culture in 2002, and Friendster in 2002. However, the first profitable mass social networking website was the South Korean service, Cyworld. Cyworld initially launched as a blog-based website in 1999 and social networking features were added to the website in 2001. Other social networking websites emerged like Myspace in 2002, LinkedIn in 2003, and Bebo in 2005. In 2009, the social networking website Facebook (launched in 2004) became the largest social networking website in the world. Active users of Facebook increased from just a million in 2004 to over 750 million by the year 2011. Making internet-based social networking both a cultural and financial phenomenon.
  • 2.7K
  • 07 Nov 2022
Topic Review
Pharmacognosy
Pharmacognosy is the study of medicinal drugs derived from plants or other natural sources. The American Society of Pharmacognosy defines pharmacognosy as "the study of the physical, chemical, biochemical and biological properties of drugs, drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources". It is also defined as the study of crude drugs.
  • 2.7K
  • 09 Nov 2022
Topic Review
Spectrum
A spectrum (plural spectra or spectrums) is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors in visible light after passing through a prism. As scientific understanding of light advanced, it came to apply to the entire electromagnetic spectrum. It thereby became a mapping of a range of magnitudes (wavelengths) to a range of qualities, which are the perceived "colors of the rainbow" and other properties which correspond to wavelengths that lie outside of the visible light spectrum. Spectrum has since been applied by analogy to topics outside optics. Thus, one might talk about the "spectrum of political opinion", or the "spectrum of activity" of a drug, or the "autism spectrum". In these uses, values within a spectrum may not be associated with precisely quantifiable numbers or definitions. Such uses imply a broad range of conditions or behaviors grouped together and studied under a single title for ease of discussion. Nonscientific uses of the term spectrum are sometimes misleading. For instance, a single left–right spectrum of political opinion does not capture the full range of people's political beliefs. Political scientists use a variety of biaxial and multiaxial systems to more accurately characterize political opinion. In most modern usages of spectrum there is a unifying theme between the extremes at either end. This was not always true in older usage.
  • 2.7K
  • 11 Nov 2022
Topic Review
Phthalocyanine Blue BN
Phthalocyanine Blue BN, also called by many names (EINECS 205-685-1), is a bright, crystalline, synthetic blue pigment from the group of phthalocyanine dyes. Its brilliant blue is frequently used in paints and dyes. It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids. It has the appearance of a blue powder, insoluble in most solvents including water.
  • 2.7K
  • 01 Dec 2022
Topic Review
E-Textiles for Sports and Fitness Sensing
E-textiles have emerged as a fast-growing area in wearable technology for sports and fitness due to the soft and comfortable nature of textile materials and the capability for smart functionality to be integrated into familiar sports clothing.
  • 2.7K
  • 26 Feb 2024
Topic Review
Public Interest Registry
Public Interest Registry is a Reston, Virginia-based not-for-profit created by the Internet Society in 2002 to manage the .ORG top-level domain. It took over operation of .ORG in January 2003 and launched the .NGO and .ONG top-level domains in March 2015. In November 2019, it was announced the Public Interest Registry would be sold by the Internet Society to private equity investment firm Ethos Capital for 1.135 billion USD, but in April 2020, ICANN decided to reject the sale.
  • 2.7K
  • 05 Dec 2022
Topic Review
Stereoselective Synthesis of Chiral Molecules
Metal/lipase-combo catalyzed dynamic kinetic resolution (DKR) of racemic chiral alcohols is a general and practical process to obtain the corresponding enantiopure esters R with quantitative conversion. The use of known Ru-catalysts as well as newly developed homogeneous and heterogeneous metal catalysts (Fe, V) contributed to make the DKR process more sustainable and to expand the substrate scope of the reaction. In addition to classical substrates, challenging allylic alcohols, tertiary alcohols, C1-and C2-symmetric biaryl diols turned out to be competent substrates. Synthetic utility further emerged from the integration of this methodology into cascade reactions leading to linear/cyclic chiral molecules with high ee through the formation of multiple bonds, in a one-pot procedure. 
  • 2.7K
  • 08 Oct 2021
Topic Review
Echinacea purpurea (L.) Moench
Echinacea purpurea (L.) Moench (EP)is a perennial herbaceous flowering plant, commonly known as purple coneflower and it belongs to the Asteraceae family. The Echinacea genus is originally from North America, in the United States, and its species are widely distributed throughout. There are nine different species of Echinacea, but only three of them are used as medicinal plants with wide therapeutic uses: Echinacea purpurea (L.) Moench, Echinacea pallida (Nutt.) Nutt. and Echinacea angustifolia DC. Several significant groups of bioactive compounds with pharmacological activities have been isolated from Echinacea species. Numerous beneficial effects have been demonstrated about these compounds.
  • 2.7K
  • 20 May 2022
Topic Review
Sustainable Use of RAP Materials for Pavement Construction
RAP is suitable for re-construction or re-surfacing roads. RAP contains well-graded fine aggregates covered with asphalt cement and must be properly crushed and categorised. The four most frequently used processes for recycling RAP conserve natural resources and make pavement construction sustainable.
  • 2.7K
  • 24 Jun 2022
Topic Review
The Concept of Integrated Municipal Solid Waste Management
Municipal solid waste (MSW) management is one of the key challenges of environmental, economic and social importance. It is a global problem regardless of economic development level and political orientation, and also applies to a country such as Belarus. 
  • 2.7K
  • 08 Feb 2023
Topic Review
ELVs Recycling in Developing Countries
End-of-life vehicle is a vehicle that has reached the end of its useful life and requires proper treatment.
  • 2.7K
  • 28 Sep 2021
Topic Review
Recrystallization
In chemistry, recrystallization is a technique used to purify chemicals. By dissolving both impurities and a compound in an appropriate solvent, either the desired compound or impurities can be removed from the solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, recrystallization can refer to the natural growth of larger ice crystals at the expense of smaller ones.
  • 2.7K
  • 14 Oct 2022
Topic Review
Search Engine Manipulation Effect
The search engine manipulation effect (SEME) is the change in consumer preferences from manipulations of search results by search engine providers. SEME is one of the largest behavioral effects ever discovered. This includes voting preferences. A 2015 study indicated that such manipulations could shift the voting preferences of undecided voters by 20 percent or more and up to 80 percent in some demographics. The study estimated that this could change the outcome of upwards of 25 percent of national elections worldwide. On the other hand, Google denies secretly re-ranking search results to manipulate user sentiment, or tweaking ranking specially for elections or political candidates.
  • 2.7K
  • 02 Dec 2022
Topic Review
Ignition of Fires from Electrical Causes
In a number of countries, somewhere around 20% of reported building fires are due to electrical faults or failures. There can be a number of mechanisms responsible, but arcing in air and hot-surface ignitions of combustible materials are important causes. Details of these two mechanisms are reviewed. It is shown that even though arcing in air produces temperatures greatly higher than the ignition temperature of any ignitable solid, this does not always result in ignition. With regards to ignitions from hot surfaces or objects, it is shown that the area of the hot object presented to the ignitable material is a crucial variable.
  • 2.7K
  • 10 Aug 2023
Topic Review
Cell Lines from Strawberry Fruits
Fleshy fruits are crucial in a healthy human diet but highly perishable due to their delicate texture at full ripe stage. Tomato and strawberry are leading crops which belongs to this fleshy fruit category, as well as models for ripening of climacteric and non-climateric fruits, respectively. In this regard, cell cultures derived from strawberry fruit at different developmental stages have been obtained to evaluate their potential use to study different aspects of strawberry ripening. Callus from leaf and cortical tissue of unripe-green, white, and mature-red strawberry fruits were induced in a medium supplemented with 11.3 M 2,4-dichlorophenoxyacetic acid (2,4-D) under darkness. This 2,4-D chemical reagent is an herbicide which mimics the action of the natural plant hormone auxin, widely used in plant cell culture. The transfer of the established callus from darkness to light induced the production of anthocyanin. The replacement of 2,4-D by abscisic acid (ABA) noticeably increased anthocyanin accumulation in green-fruit callus. Cell walls were isolated from the different fruit cell lines and from fruit receptacles at equivalent developmental stages and sequentially fractionated to obtain fractions enriched in soluble pectins, ester bound pectins, xyloglucans (XG), and matrix glycans tightly associated with cellulose microfibrils. These fractions were analyzed by cell wall carbohydrate microarrays. In fruit receptacle samples, pectins were abundant in all fractions, including those enriched in matrix glycans. The amount of pectin increased from green to white stage, and later these carbohydrates were solubilized in red fruit. Apparently, XG content was similar in white and red fruit, but the proportion of galactosylated XG increased in red fruit. Cell wall fractions from callus cultures were enriched in extensin and displayed a minor amount of pectins. Stronger signals of extensin antibodies were detected in sodium carbonate fraction, suggesting that these proteins could be linked to pectins. Overall, the results obtained suggest that fruit cell lines could be used to analyze hormonal regulation of color development in strawberry but that the cell wall remodelling process associated with fruit softening might be masked by the high presence of extensin in callus cultures.
  • 2.7K
  • 24 Nov 2020
Topic Review
Wasp Venom Biochemical Components
Wasps, members of the order Hymenoptera, are distributed in different parts of the world, including Brazil, Thailand, Japan, Korea, and Argentina. The lifestyles of the wasps are solitary and social. Social wasps use venom as a defensive measure to protect their colonies, whereas solitary wasps use their venom to capture prey. Chemically, wasp venom possesses a wide variety of enzymes, proteins, peptides, volatile compounds, and bioactive constituents, which include phospholipase A2, antigen 5, mastoparan, and decoralin. The bioactive constituents have anticancer, antimicrobial, and anti-inflammatory effects. However, the limited quantities of wasp venom and the scarcity of advanced strategies for the synthesis of wasp venom’s bioactive compounds remain a challenge facing the effective usage of wasp venom. Solid-phase peptide synthesis is currently used to prepare wasp venom peptides and their analogs such as mastoparan, anoplin, decoralin, polybia-CP, and polydim-I. 
  • 2.7K
  • 23 Mar 2021
Topic Review
Bow Shocks in Astrophysics
Bow shocks form the boundary between a magnetosphere and an ambient (or at least surrounding) magnetized medium. This occurs when the magnetic field of an astrophysical object interacts with the nearby flowing ambient plasma. For example, when the solar wind, flowing with a relative speed of order 400 km/s, encounters the magnetic field of Earth, a bow shape boundary forms. For Earth and other magnetized planets, it is the boundary at which the speed of the stellar wind abruptly drops as a result of its approach to the magnetopause. For stars, this boundary is typically the edge of the astrosphere, where the stellar wind meets the interstellar medium.
  • 2.7K
  • 27 Oct 2022
Topic Review
HADOPI Law
The French HADOPI law or Creation and Internet law (French: Haute Autorité pour la Diffusion des Œuvres et la Protection des droits d'auteur sur Internet, pronounced [ot‿ɔtɔʁite puʁ la difyzjɔ̃ dɛz‿œvʁ e la pʁɔtɛksjɔ̃ de dʁwa d‿otœʁ syʁ ɛ̃tɛʁnɛt]; or, loosely in English, "Supreme Authority for the Distribution of Works and Protection of Copyright on the Internet") was introduced during 2009, providing what is known as a graduated response as a means to encourage compliance with copyright laws. HADOPI is the acronym of the government agency created to administer it. The part of the HADOPI law that allowed for suspension of Internet access to a repeat infringer was revoked on 8 July 2013 by the French government because that penalty was considered to be disproportionate. The power to impose fines or other sanctions on repeat infringers remains in effect. In January 2022, the Hadopi agency merged with the High Audiovisual Council (CSA), to form the Regulatory Authority for Audiovisual and Digital Communication (Autorité de régulation de la communication audiovisuelle et numérique; ARCOM).
  • 2.7K
  • 04 Nov 2022
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