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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
Nanojoining
Nanojoining is the process of joining two or more surfaces together using nanomaterials as the primary building blocks. This includes, but is not limited to, nanosoldering, nanobrazing, nanowelding, nanoscale diffusion bonding, and additive manufacturing. Note that, like with conventional soldering and brazing, only the filler metal undergoes melting, not the base material. Nanomaterials are materials in which at least one dimension 100 nm or less and include 0-D (e.g. nanoparticles, 1-D (e.g. nanowires and nanorods), 2-D (e.g. graphene), and 3-D (e.g. nanofoam) materials. Nanomaterials exhibit several notable properties that allow joining to occur at temperatures lower than the melting temperature of their bulk counterpart. For example, the melting temperature of Ag is 961.78 °C, but Ag nanomaterials begin to melt at a much lower temperature that is dependent depending on the size and shape. These properties include high surface area to volume ratio, the Gibbs-Thompson effect, and high surface energy. The low joining temperature of nanomaterials has been exploited numerous times for flexible electronics, printable electronics, and soldering applications; only within the last two decades have they been explored for high-temperature joining applications (>450 °C).
  • 2.7K
  • 07 Jul 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
LINC Complex in Sperm Development
The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men.
  • 2.7K
  • 04 Dec 2020
Topic Review
Responsive Traffic Signaling System Using Graph Theory/VDM-SL
The Responsive Traffic Signaling System Using Graph Theory and Vienna Development Method Specification Language (VDM-SL) is a robust traffic monitoring and signaling system that improves signal efficiency by providing a responsive scheme; appropriate routes; a mechanism for emergency vehicles and pedestrians in real-time using VDM-SL formal method and graph theory. A formal model is constructed by considering objects, such as wireless sensors and cameras that are used for collecting information. Graph theory is used to represent the network and find appropriate routes. Unified Modeling Language is used to design the system requirements. The graph-based framework is converted into a formal model by using VDM-SL. The model has been validated and analyzed using many facilities available in the VDM-SL toolbox. 
  • 2.7K
  • 01 Nov 2021
Topic Review
Sustainable Innovation Strategies for Increased Competition among Companies
Companies have concerns about environmental issues, translated into the implementation of sustainable practices in their business models, not because they are legal obligations, but because they incorporate sustainability in their strategic vision. Thus, companies add considerable value to their value chain and obtain a better strategic positioning in relation to competitors. There are companies intend to implement innovative sustainable practices and that some companies have a business model that already incorporates sustainability strategies. 
  • 2.7K
  • 09 Jun 2022
Topic Review
Hormones for Oral Bone and Periodontal Tissue Engineering
Hormones are unique regulatory chemicals that govern fertility, growth, maturation, and microenvironmental maintenance, in addition to power generation, usage, and storage. Hormones play a fundamental function in the maintenance of the integrity of both periodontium and bone. Bone tissue is made up of many cell types and an extracellular matrix that is mostly made up of collagen proteins. Bone’s primary roles are structural support, mechanical motions, blood cell formation, and tissue preservation; it also serves as a depot of calcium and phosphate ions in the body.
  • 2.7K
  • 26 Jul 2022
Topic Review
Shinbutsu-shūgō
Shinbutsu-shūgō (神仏習合, "syncretism of kami and buddhas"), also called Shinbutsu-konkō (神仏混淆, "jumbling up" or "contamination of kami and buddhas"), is the syncretism of Buddhism and kami worship that was Japan's only organized religion up until the Meiji period. Beginning in 1868, the new Meiji government approved a series of laws that separated Japanese native kami worship, on one side, from Buddhism which had assimilated it, on the other. When Buddhism was introduced from China in the Asuka period (6th century), rather than discarding the old belief system, the Japanese tried to reconcile the two, assuming both were true. As a consequence, Buddhist temples (寺, tera) were attached to local Shinto shrines (神社, jinja) and vice versa and devoted to both kami and buddhas. The local religion and foreign Buddhism never quite fused, but remained however inextricably linked all the way to the present day, always interacting. The depth of the resulting influence of Buddhism on local religious beliefs can be seen for example in the fact that much of Shinto's conceptual vocabulary and even the types of Shinto shrines we see today, with a large worship hall and religious images, are themselves of Buddhist origin. The formal separation of Buddhism from Shinto took place only as recently as the end of the 19th century; however, in many ways, the blending of the two still continues. The term shinbutsu shūgō itself was coined during the early modern era (17th century) to refer to the amalgamation of kami and buddhas in general, as opposed to specific currents within Buddhism which did the same, e.g. Ryōbu Shintō and Sannō Shintō. The term may have a negative connotation of bastardization and randomness.
  • 2.7K
  • 24 Oct 2022
Topic Review
Tiva-C LaunchPad
The Tiva-C (a.k.a. TM4C) LaunchPads are inexpensive self-contained, single-board microcontrollers, about the size of a credit card, featuring an ARM Cortex-M4F 32-bit CPU operating at 80 to 120 MHz, manufactured by Texas Instruments. The TM4C Series TM4C123G LaunchPad is an upgrade from TI's Stellaris LaunchPad adding support options for motion control PWMs and USB Host functionality. The more recently released TM4C1294 Connected LaunchPad is the first cloud-connected offering in TI's LaunchPad ecosystem and provides a solid foundation for beginning and evaluating embedded IoT designs. There are many I/O pins (40 to 80 depending upon version) that have multi-personality. This means that they can be easily configured as digital inputs or outputs, analog inputs and outputs or other functions, allowing a great variety of applications, are just the multiple serial ports have the ability to interface with more items such as test cards or other communication modules, etc. Among those pins there are included the GND and POWER (3.3 V) pins. The clock is 80 or 120 MHz (vers based), which makes them 5 to over 7 times faster than the Arduino Uno's 16 MHz ATmega328P microcontroller. As with any Cortex M4, the CPU has some DSP (digital signal processor) instructions, with some limitations. One can do signal processing, for example, sampling a human voice with a good quality, able to be processed in MATLAB. The CPU contains the optional floating-point unit with single-precision floating point operations supported. They have an additional USB port which can act as USB host, allowing the connection of multiple devices and the "Connected" one has an integrated 10/100 Ethernet MAC+PHY for Internet connectivity. They also have a temperature sensor and on-board LED(s) and RGB LED(s), which allows you to generate various colors by combining the three basic colors (red, blue and green) of the additive color synthesis. The Tiva/TM4C LaunchPads come preloaded with software to demonstrate many of the capabilities of the ARM microcontroller and with a quickstart application to get up and running within minutes.
  • 2.7K
  • 01 Dec 2022
Topic Review
Ethyl Acetate Hydrogenation
Ethyl acetate hydrogenation is the reverse reaction of ethanol dehydrogenation. Tuthenium complexes acting in homogeneous phase, at very low temperatures, promote both ethanol dehydrogenation and ethylacetate hydrogenation.
  • 2.7K
  • 30 Mar 2023
Topic Review
Naturally alkaloids as Antimicrobial agents
Antibiotic resistance is a serious threat to public health and new antimicrobial compounds are urgently needed. One of the most promising classes for the development of new antimicrobials are plant-derived alkaloids.
  • 2.7K
  • 25 Aug 2020
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
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
Rhamnus (Genus)
Rhamnus is a genus of about 110 accepted species of shrubs or small trees, commonly known as buckthorns in the family Rhamnaceae. Its species range from 1 to 10 meters tall (rarely to 15 m) and are native mainly in east Asia and North America, but found throughout the temperate and subtropical Northern Hemisphere, and also more locally in the subtropical Southern Hemisphere in parts of Africa and South America. Both deciduous and evergreen species occur. The leaves are simple, 3 to 15 centimeters long, and arranged alternately or in opposite pairs, or almost paired (subopposite). One distinctive character of many buckthorns is the way the veination curves upward towards the tip of the leaf. The plant bears fruits which are black or red berry-like drupe. The name is due to the woody spine on the end of each twig in many species. In the United States , Buckthorn is considered an invasive species by many local jurisdictions and state governments, such as Minnesota or Wisconsin.
  • 2.7K
  • 31 Oct 2022
Topic Review
Neurological Effects of Tualang Honey
Tualang honey exerted neurological effects namely nootropic, antinociceptive, stress-relieving, anti-depressant, and anxiolytic. These effects are attributed to its antioxidant and anti-inflammatory properties.
  • 2.7K
  • 23 Sep 2021
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
Whole-Brain Models
Whole-brain models are sets of equations that describe the dynamics and interactions between neural populations in different brain regions. Most whole-brain models are built considering three basic elements: brain parcellation, anatomical connectivity matrix, and local dynamics.
  • 2.7K
  • 21 Oct 2020
Topic Review
Metal Nanoclusters
Metal nanoclusters (NCs), comprising only a few to roughly hundreds of metal atoms, have a metal core-protective agent shell structure. Owing to the size of metal NCs approaching the Fermi wavelength of electrons, the spatial confinement of free electrons in metal NCs generates discrete electronic transitions, thereby exhibiting intriguing molecular-like properties. Therefore, metal NCs are deemed to bridge the gap between molecules and nanoparticles.
  • 2.7K
  • 01 Dec 2020
Topic Review
PYHIN Proteins
Pyrin and hematopoietic interferon-inducible nuclear (HIN) domain (PYHIN) proteins have originally emerged as sensors of exogenous DNA and stimulators of the innate immune response. Recent studies, however, indicate that nuclear PYHIN protein family members restrict viral replication by silencing gene expression, in a sensing-independent fashion. Not surprisingly, viruses evolved diverse ways to overcome such cellular defences.
  • 2.7K
  • 14 Jan 2021
Topic Review
Eye Involvement in Wilson’s Disease
Wilson’s disease (WD) is an autosomal recessive genetic disorder due to a mutation of the ATP7B gene, resulting in impaired hepatic copper excretion and accumulation in various tissues. Ocular findings are one of the hallmarks of the disease. Many ophthalmological manifestations have been described and new techniques are currently available to improve their diagnosis and to follow their evolution. The most common ocular findings seen in WD patients are Kayser–Fleischer ring (KFR) and sunflower cataracts. Other ocular manifestations may involve retinal tissue, visual systems and eye mobility. Diagnosis and follow-up under decoppering treatment of these ocular findings are generally easily performed with slit-lamp examination (SLE). However, new techniques are available for the precocious detection of ocular findings due to WD and may be of great value for non-experimented ophthalmologists and non-ophthalmologists practitioners. 
  • 2.7K
  • 18 Aug 2022
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