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Topic Review
Hedgehog Signaling Pathway
The hedgehog (Hh) pathway is a sophisticated conserved cell signaling pathway that plays an essential role in controlling cell specification and proliferation, survival factors, and tissue patterning formation during embryonic development.
  • 2.2K
  • 10 Jan 2022
Topic Review
Spermidine
Spermidine, a natural polyamine, exists in almost all human tissues, exhibiting broad properties like anti-aging, autophagy induction, anti-inflammation, anti-oxidation, cell proliferation activation, and ion channel regulation.
  • 2.2K
  • 04 Aug 2022
Topic Review
Graphics Environment Manager
GEM (for Graphics Environment Manager) was an operating environment created by Digital Research (DRI) for use with the DOS operating system on Intel 8088 and Motorola 68000 microprocessors. GEM is known primarily as the graphical user interface (GUI) for the Atari ST series of computers, and was also supplied with a series of IBM PC-compatible computers from Amstrad. It also was available for standard IBM PC, at the time when the 6 MHz IBM PC AT (and the very concept of a GUI) was brand new. It was the core for a small number of DOS programs, the most notable being Ventura Publisher. It was ported to a number of other computers that previously lacked graphical interfaces, but never gained popularity on those platforms. DRI also produced X/GEM for their FlexOS real-time operating system with adaptations for OS/2 Presentation Manager and the X Window System under preparation as well.
  • 2.2K
  • 20 Oct 2022
Topic Review
Ceramic-Based Hybrid Supercapacitors
Supercapacitors (SCs) have attracted considerable attention among various energy storage devices due to their high specific capacity, high power density, long cycle life, economic efficiency, environmental friendliness, high safety, and fast charge/discharge rates. SCs are devices that can store large amounts of electrical energy and release it quickly, making them ideal for use in a wide range of applications. They are often used in conjunction with batteries to provide a power boost when needed and can also be used as a standalone power source. They can be used in various potential applications, such as portable equipment, smart electronic systems, electric vehicles, and grid energy storage systems.
  • 2.2K
  • 02 Nov 2022
Topic Review
Govardhana Sila
A Govardhana Shila is rock from the Govardhan Hill in Braj. Govardhan Hill holds a unique position in Hindu scriptures related to Krishna, the land called Vrij where He was born. Known as Govardhan or Giriraj and being the sacred center of Braj, it is identified as a natural form of Krishna. Indian art overwhelmingly prefers the iconic image, but some aniconism does occur in folk worship, early Buddhism, Shiva's Banalinga, and Vishnu's Saligrama Sila (murthi)). They have solar significance, and their use in worship predates the Hindu period in India . The stone is usually brown in color. Govardhan, a very famous place of Hindu pilgrimage, is located 26 km west of Mathura (154 km from New Delhi) on the state highway to Deeg. Govardhan is located on a narrow sandstone hill known as Giriraj which is about 8 km in length. When Chaitanya Mahaprabhu did parikrama (circumambulation) of Govardhana Hill while visiting Vrindavana in 1515 AD, he did not walk on the hill because he considered Govardhana as non-different from Lord Krishna. Therefore, traditionally Vaishnavas don’t step on Govardhan hill.
  • 2.2K
  • 01 Dec 2022
Topic Review
DPP4 Inhibitors on COVID19 Outcomes
Although relatively new in the therapeutic landscape for managing type 2 diabetes (T2D), dipeptidyl-peptidase 4 (DPP4) inhibitors have gained widespread popularity, due to their glycemic efficacy, low risk of hypoglycemic episodes and oral route of administration. DPP4, a cell-bound serine protease abundantly expressed on lymphocytes, epithelial and endothelial cells, plays critical roles in the modulation of glucose homeostasis and inflammatory immune responses. Also, given its potential to serve as an adjunctive functional receptor for the emerging Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) to gain entry into the host, inhibition of DPP4 has been proposed as an alternative and multifaceted strategy to prevent severe clinical manifestations of the SARS-CoV-2 related illness (COVID-19), which are commonly observed in T2D patients. However, the inherent risk of mast cells hyper-activation and the lack of a clear demonstration of SARS-CoV-2 binding to DPP4, may raise some concerns and controversy.
  • 2.2K
  • 06 Nov 2020
Topic Review
Nanostructured Materials-Enabled Biosensors
A biosensor is an integrated receptor-transducer device, which can convert a biological response into an electrical signal.
  • 2.2K
  • 18 Mar 2021
Topic Review
Collagen D-Band Periodicity
The molecules follow a quarter-staggered fashion packing, which leads to the formation of the so call D-band periodicity. This D-band periodicity is a repeating banding pattern of about 67 nm (depending on the different tissue) and includes gap and overlap regions. Collagen fibrils form bundles and fibers by appropriate alignment.
  • 2.2K
  • 06 Apr 2022
Topic Review
Modification of the Surface of Wood with Plasma
Wood modification is an excellent and increasingly used method to expand the application of woody materials. Traditional methods, such as chemical or thermal, have been developed for the targeted improvement of some selected properties, unfortunately typically at the expense of others. These methods generally alter the composition of wood, and thus its mechanical properties, and enhance dimensional stability, water resistance, or decrease its susceptibility to microorganisms. Although conventional methods achieve the desired properties, they require a lot of energy and chemicals, therefore research is increasingly moving towards more environmentally friendly processes. The advantage of modern methods is that in most cases, they only modify the surface and do not affect the structure and mechanical properties of the wood, while reducing the amount of chemicals used. Cold plasma surface treatment is one of the cheapest and easiest technologies with a limited burden on the environment
  • 2.2K
  • 27 May 2022
Topic Review
The Bioavailability of Drugs
Drug bioavailability is a crucial aspect of pharmacology, affecting the effectiveness of drug therapy. Understanding how drugs are absorbed, distributed, metabolized, and eliminated in patients’ bodies is essential to ensure proper and safe treatment. In addition to biochemical activity, bioavailability also plays a critical role in achieving the desired therapeutic effects. This may seem obvious, but it is worth noting that a drug can only produce the expected effect if the proper level of concentration can be achieved at the desired point in a patient’s body. Given the differences between patients, drug dosages, and administration forms, understanding and controlling bioavailability has become a priority in pharmacology. 
  • 2.2K
  • 03 Jan 2024
Topic Review
Stationary Action Principle
The stationary action principle – also known as the principle of least action – is a variational principle that, when applied to the action of a mechanical system, yields the equations of motion for that system. The principle states that the trajectories (i.e. the solutions of the equations of motion) are stationary points (a.k.a. critical points) of the system's action functional. The term "least action" is a historical misnomer since the principle has no minimality requirement: the value of the action functional need not be minimal (even locally) on the trajectories. The principle can be used to derive Newtonian, Lagrangian and Hamiltonian equations of motion, and even general relativity (see Einstein–Hilbert action). In relativity, a different action must be minimized or maximized. The classical mechanics and electromagnetic expressions are a consequence of quantum mechanics. The stationary action method helped in the development of quantum mechanics. In 1933, the physicist Paul Dirac demonstrated how this principle can be used in quantum calculations by discerning the quantum mechanical underpinning of the principle in the quantum interference of amplitudes. Subsequently Julian Schwinger and Richard Feynman independently applied this principle in quantum electrodynamics. The principle remains central in modern physics and mathematics, being applied in thermodynamics, fluid mechanics, the theory of relativity, quantum mechanics, particle physics, and string theory and is a focus of modern mathematical investigation in Morse theory. Maupertuis' principle and Hamilton's principle exemplify the principle of stationary action. The action principle is preceded by earlier ideas in optics. In Ancient Greece , Euclid wrote in his Catoptrica that, for the path of light reflecting from a mirror, the angle of incidence equals the angle of reflection. Hero of Alexandria later showed that this path was the shortest length and least time. Scholars often credit Pierre Louis Maupertuis for formulating the principle of least action because he wrote about it in 1744 and 1746. However, Leonhard Euler discussed the principle in 1744, and evidence shows that Gottfried Leibniz preceded both by 39 years.
  • 2.2K
  • 14 Oct 2022
Topic Review
Diels–Alder Cycloaddition Reactions
Diels–Alder cycloaddition reaction is one of the most powerful strategies for the construction of six-membered carbocyclic and heterocyclic systems, in most cases with high regio- and stereoselectivity. An insight into the most relevant advances on sustainable Diels–Alder reactions since 2010 is provided. Various environmentally benign solvent systems are discussed, namely bio-based derived solvents, polyethylene glycol, deep eutectic solvents, supercritical carbon dioxide, water and water-based aqueous systems.
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  • 25 Mar 2022
Topic Review
Impact of Virtual Reality on Tourism
As an advanced technology, virtual reality (VR) could contribute substantially to the tourism industry, but differently than existing technologies. In fact, VR creates artificial environments like the real world, which are thus immersive virtual environments that are also more realistic. These features might foster attraction and engagement from additional tourists and improve their perceptions of different destinations (e.g., theme parks, cultural heritage centers, or museums).
  • 2.2K
  • 30 Oct 2023
Topic Review
Yuktibhāṣā
Yuktibhāṣā (Malayalam: യുക്തിഭാഷ, lit. 'Rationale'), also known as Gaṇita-yukti-bhāṣā:xxi and Gaṇitanyāyasaṅgraha (Compendium of Astronomical Rationale), is a major treatise on mathematics and astronomy, written by the India n astronomer Jyesthadeva of the Kerala school of mathematics around 1530. The treatise, written in Malayalam, is a consolidation of the discoveries by Madhava of Sangamagrama, Nilakantha Somayaji, Parameshvara, Jyeshtadeva, Achyuta Pisharati, and other astronomer-mathematicians of the Kerala school. It also exists in a Sanskrit version, with unclear author and date, composed as a rough translation of the Malayalam original. The work contains proofs and derivations of the theorems that it presents. Modern historians used to assert, based on the works of Indian mathematics that first became available, that early Indian scholars in astronomy and computation lacked in proofs, but Yuktibhāṣā demonstrates otherwise. Some of its important topics include the infinite series expansions of functions; power series, including of π and π/4; trigonometric series of sine, cosine, and arctangent; Taylor series, including second and third order approximations of sine and cosine; radii, diameters and circumferences; and tests of convergence. Yuktibhāṣā mainly gives rationale for the results in Nilakantha's Tantra Samgraha. It is considered an early text on the ideas of calculus, predating Newton and Leibniz by centuries. The treatise was largely unnoticed outside India, as it was written in the local language of Malayalam. In modern times, due to wider international cooperation in mathematics, the wider world has taken notice of the work. For example, both Oxford University and the Royal Society of Great Britain have given attribution to pioneering mathematical theorems of Indian origin that predate their Western counterparts.
  • 2.2K
  • 21 Nov 2022
Topic Review
Additive Manufacturing of Magnesium-Based Alloys through Laser-Based Approach
Magnesium alloys continue to be important in the context of modern and lightweight technologies. The increased use of Mg each year indicates a rise in demand for alloys containing Mg. With additive manufacturing (AM), components can be produced directly in a net shape, providing new ideas relating to the new prospects for Mg-based materials. 
  • 2.2K
  • 23 Nov 2022
Topic Review
SDA Bocconi School of Management
SDA Bocconi School of Management (SDA standing for Scuola di Direzione Aziendale) is the graduate business school of Bocconi University. SDA Bocconi offers executive, custom and MBA programs, as well as specialized masters, and regularly takes on research projects on commission. SDA Bocconi School of Management also has an offshore presence in Mumbai, India called the SDA Bocconi Asia Center. In 1998, SDA Bocconi was the first school in Italy to be accredited by EQUIS and is now one of only 100 business schools worldwide to hold the "triple crown", having been accredited by three international accreditation associations: AACSB, EQUIS and AMBA (Association of MBAs). The School has also been accredited by CSQNet and holds the ISO 9001:2000 quality rating from the Funded Projects Services Center.
  • 2.2K
  • 23 Nov 2022
Topic Review
Office Online
Office Online (known before 2014 as Office Web Apps and as of July 2019 as Office) is an online office suite offered by Microsoft, which allows users to create and edit files using lightweight Microsoft Office web apps: Word, Excel, PowerPoint and OneNote. The offering also includes Outlook.com, People, Calendar and OneDrive, all of which are accessible from a unified app switcher. Users can install the on-premises version of this service, called Office Online Server, in private clouds in conjunction with SharePoint, Microsoft Exchange Server and Microsoft Lync Server.
  • 2.2K
  • 25 Nov 2022
Topic Review
Influencer Engagement on Social Media
The interactive capabilities of social media (SM) can provide a conceptual parallel to the conversational nature underlying the concept of engagement. For example, SM users’ interactions with specific brands are concrete manifestations of engagement marked by varying degrees of affective and/or cognitive and/or behavioral investment.
  • 2.2K
  • 19 Oct 2023
Topic Review
Applications of Metallic Glasses
Metallic glasses can be a perfect alternative to conventional crystalline biomaterials (such as 316L stainless steel, Ti or Ti-based alloys, Zr or Zr-based alloys, Co-Cr alloys, etc.) when used as coatings for surgical devices and implants inside the human body. Owing to their outstanding electrocatalytic activity and durability, metallic glasses can be considered prominent candidates for energy-storage and -conversion devices, such as fuel and electrolysis cells, and batteries. Metallic-glass systems are gaining substantial momentum in the micro- and nano-imprinting of optoelectronic devices.
  • 2.2K
  • 19 Dec 2023
Topic Review
Antigen Presentation of SARS-CoV-2 mRNA Vaccines
Infection with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019 (COVID-19), which has reached pandemic proportions. A number of effective vaccines have been produced, including mRNA vaccines and viral vector vaccines, which are now being implemented on a large scale in order to control the pandemic. The mRNA vaccines are composed of viral Spike S1 protein encoding mRNA incorporated in a lipid nanoparticle and stabilized by polyethylene glycol (PEG). The mRNA vaccines are novel in many respects, including cellular uptake and the intracellular routing, processing, and secretion of the viral protein. Because of space restrictions, viral vector vaccines not discussed in detail. The antigen presentation routes in MHC class I and class II, in relation to the induction of virus-neutralizing antibodies and cytotoxic T-lymphocytes, will be reviewed. In rare cases, mRNA vaccines induce unwanted immune mediated side effects. In rare cases, the mRNA-based vaccines may lead to an anaphylactic reaction. This reaction may be triggered by PEG. The intracellular routing of PEG and potential presentation in the context of CD1 will be discussed. 
  • 2.2K
  • 11 Oct 2021
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