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Topic Review
Gas Chromatography - Vacuum Ultraviolet Spectroscopy (GC-VUV)
Gas Chromatography - Vacuum Ultraviolet (GC-VUV) spectroscopy is a universal detection platform for gas chromatography. The first benchtop detector was introduced in 2014 with detection capabilities between 120 - 240 nm. This portion of the ultraviolet spectrum had historically been restricted to bright source synchrotron facilities due to significant background absorption challenges inherent to working within the wavelength range. Further detector platform development has extended the wavelength detection range out from 120 - 430 nm. VUV detection provides both qualitative and quantitative spectral information for most gas phase compounds. GC-VUV spectral data is three dimensional (time, absorbance, wavelength) and specific to chemical structure. Nearly all compounds absorb in the VUV region of the electromagnetic spectrum with the exception of carrier gases hydrogen, helium, and argon. The high energy, short wavelength VUV photons probe electronic transitions in almost all chemical bonds including ground state to excited state. The result is spectral "fingerprints" that are specific to individual compound structure and can be readily identified by the VUV library. Unique VUV spectra enable closely related compounds such as structural isomers to be clearly differentiated. VUV detectors complement mass spectrometry, which struggles with characterizing constitutional isomers and compounds with low mass quantitation ions. VUV spectra can also be used to deconvolve analyte co-elution, resulting in an accurate quantitative representation of individual analyte contribution to the original response. This characteristically lends itself to significantly reducing GC runtimes through flow rate-enhanced chromatographic compression. VUV spectroscopy follows the simple linear relationship between absorbance and concentration described by the Beer-Lambert Law resulting in more accurate retention time-based identification. VUV absorbance spectra also exhibit feature similarity within compound classes, meaning VUV detectors can rapidly compound class characterization in complex samples through compound spectral shape and retention index information. Advances in technology reduces the typical group analysis data processing time from 15-30 minutes to <1 minute per sample.
  • 3.4K
  • 17 Nov 2022
Topic Review
Flashline Mars Arctic Research Station
The Flashline Mars Arctic Research Station (FMARS) is the first of two simulated Mars habitats (or Mars Analog Research Stations) established and maintained by the Mars Society.
  • 3.4K
  • 10 Oct 2022
Topic Review
The Shoot Apical Meristem
The shoot apical meristem (SAM) gives rise to the aerial structure of plants by producing lateral organs and other meristems. The SAM is responsible for plant developmental patterns, thus determining plant morphology and, consequently, many agronomic traits such as the number and size of fruits and flowers and kernel yield.
  • 3.4K
  • 01 Feb 2024
Topic Review
Motorcycle Market
In many cities, urbanization has led to a rapid increase in the demand for mobility. Most of this new demand has been satisfied by the individual private transport industry, within which motorcycles have an important share: around 30% of the vehicles in the world are motorcycles. Thus, the motorcycle market has experienced an upward trend, especially in developing countries. That uncontrolled growth brings along mobility, accidents, and environment-related issues that concern policy-makers. Research trends regarding this matter evidence that greenhouse gas emissions, sustainability, environmental impact, and developing countries are the topics of greater interest for researchers. In addition, taking into account the needs of modern cities, sustainable modes of transport such as electric and shared mobility are compulsory as a priority on governments' agendas. 
  • 3.4K
  • 26 Oct 2021
Topic Review
Mobile Launcher Platform
A mobile launcher platform, also known as mobile launch platform, is a steel structure used to support a large multistage space vehicle which is assembled (stacked) vertically in an integration facility (e.g. the Vehicle Assembly Building) and then transported by a crawler-transporter (CT) to a launch pad. This becomes the support structure for launch. Alternatives to this method include horizontal assembly and transport to the pad, as used by Russia; and assembling the vehicle vertically on the launch pad, as the United States used for smaller launch vehicles. The use of mobile launcher platforms dates back to the "Integrate-Transfer-Launch" (ITL) concept developed in 1965 for the Titan III launched from Cape Canaveral Space Launch Complex 40 and 41, and was adopted in 1966 for the Saturn V vehicle launched from Kennedy Space Center Launch Complex 39. Launch Complex 39 and 41 continue to use this concept.
  • 3.4K
  • 11 Nov 2022
Topic Review
Computer-Vision-Based Water Level Measurement
Water level measurement is an important component of hydrological monitoring and water resources management. Information such as runoff, water supply volumes and flood discharge is usually calculated based on water level measurement. To alleviate the problems associated with manual and contact measurements, the computer-vision-based approaches rely on the automatic acquisition and analysis of water surface images. Images allow the capture of water surfaces without interruption to provide insight into the continuous change of water level. Computer vision can automatically acquire and understand the meaningful information in images, such as the scope of water surface area, water line, gauge characters, etc., to obtain faster recognition speed and more accurate and stable results than human in the water level measurement task.
  • 3.4K
  • 26 Sep 2023
Topic Review
Additive Manufacturing Technology in Railway Infrastructure Systems
Additive manufacturing technologies, well known as three-dimensional printing (3DP) technologies, have been applied in many industrial fields, including aerospace, automobiles, shipbuilding, civil engineering and nuclear power. However, despite the high material utilization and the ability to rapidly construct complex shaped structures of 3D printing technologies, the application of additive manufacturing technologies in railway track infrastructure is still at the exploratory stage. 
  • 3.4K
  • 07 Jan 2022
Topic Review
Interplay between Polyphenols and Lysyl Oxidase Enzymes
Collagen, the most abundant structural protein found in mammals, plays a vital role as a constituent of the extracellular matrix (ECM) that surrounds cells. Collagen fibrils are strengthened through the formation of covalent cross-links, which involve complex enzymatic and non-enzymatic reactions. Lysyl oxidase (LOX) is responsible for catalyzing the oxidative deamination of lysine and hydroxylysine residues, resulting in the production of aldehydes, allysine and hydroxyallysine. These intermediates undergo spontaneous condensation reactions, leading to the formation of immature cross-links, which are the initial step in the development of mature covalent cross-links. Additionally, non-enzymatic glycation contributes to the formation of abnormal cross-linking in collagen fibrils. During glycation, specific lysine and arginine residues in collagen are modified by reducing sugars, leading to the creation of Advanced Glycation End-products (AGEs). These AGEs have been associated with changes in the mechanical properties of collagen fibers.
  • 3.4K
  • 13 Jul 2023
Topic Review
Roman Engineering
The ancient Romans were famous for their advanced engineering accomplishments, although some of their inventions were improvements on older ideas, concepts and inventions. Technology for bringing running water into cities was developed in the east, but transformed by the Romans into a technology inconceivable in Greece. The architecture used in Rome was strongly influenced by Greek and Etruscan sources. Roads were common at that time, but the Romans improved their design and perfected the construction to the extent that many of their roads are still in use today. Their accomplishments surpassed most other civilizations of their time, and after their time, and many of their structures have withstood the test of time to inspire others, especially during the Renaissance. Moreover, their contributions were described in some detail by authors such as Vitruvius, Frontinus and Pliny the Elder, so there is a printed record of their many inventions and achievements.
  • 3.4K
  • 27 Oct 2022
Topic Review
Remediation of Petroleum Contaminated Soils
Due to the development of the petroleum industrial, numerous petroleum pollutants are discharged into the soil, destroying the structure and properties of the soil, and even endangering the health of plants and humans. Microbial remediation and combined microbial methods remediation of petroleum-contaminated soil are currently recognized remediation technologies, which have the advantages of no secondary pollution, low cost and convenient operation. This entry includes the sources and composition of petroleum pollutants and their harm to soil, plants and humans. Subsequently, the focus is on the mechanism of microbial method and combined microbial methods to degrade petroleum pollutants. Finally, the challenges of the current combined microbial methods are pointed out.
  • 3.3K
  • 28 Sep 2021
Topic Review
Ultrasound Examination in Nail Apparatus Assessment in Psoriasis
The assessment of psoriatic nail changes in everyday practice is based exclusively on clinical symptoms that do not reflect the entire disease process in the nail apparatus. The use of imaging methods, especially widely available and inexpensive ultrasonography, creates the possibility of additional revealing and assessing grayscale of morphological changes of the ventral nail plate, nail bed, and matrix, as well as the attachment of the finger extensor tendon to the distal phalanx. What is more, it enables the assessment of inflammation severity in the power Doppler technique. A qualitative classification of nail plate morphological changes corresponding to the severity of psoriatic nail changes has been developed so far and attempts are being made to develop a quantitative method to assess not only the presence of changes but also the severity of inflammation. 
  • 3.3K
  • 20 May 2022
Topic Review
Neurodegenerative Diseases
Neurodegenerative diseases are affecting more and more people around the world. Current therapies only treat the symptoms and not the causes of the disease. However, the pathophysiology of these diseases is now better known. In the case of Alzheimer's disease and Parkinson's disease, some common mechanisms have been identified. One of the first known mechanisms is the accumulation of proteins: α-synuclein (Parkinson's disease), Tau (Alzheimer's disease) and β-amyloid (Alzheimer's disease and Parkinson's disease) proteins. Protein accumulation is related to a disruption of mitochondrial activity associated with cell death and oxidative stress. Inflammation is also another important mechanism, which is disrupted in these pathologies.
  • 3.3K
  • 15 Sep 2023
Topic Review
Visible-Light Photoredox Catalysis for the Thiol-Ene/Yne Reactions
Visible-light photoredox catalysis has been established as a popular and powerful tool for organic transformations owing to its inherent characterization of environmental friendliness and sustainability in the past decades. The thiol-ene/yne reactions, the direct hydrothiolation of alkenes/alkynes with thiols, represents one of the most efficient and atom-economic approaches for the carbon-sulfur bonds construction. In traditional methodologies, harsh conditions such as stoichiometric reagents or a specialized UV photo-apparatus were necessary suffering from various disadvantages. In particular, visible-light photoredox catalysis has also been demonstrated to be a greener and milder protocol for the thiol-ene/yne reactions in recent years. Additionally, unprecedented advancements have been achieved in this area during the past decade.
  • 3.3K
  • 11 Feb 2022
Topic Review
Molecular Characterization of XX Maleness
Androgens and anti-Müllerian hormone (AMH), secreted by the foetal testis, are responsible for the development of male reproductive organs and the regression of female anlagen. Virilization of the reproductive tract in association with the absence of Müllerian derivatives in the XX foetus implies the existence of testicular tissue, which can occur in the presence or absence of SRY. Recent advancement in the knowledge of the opposing gene cascades driving to the differentiation of the gonadal ridge into testes or ovaries during early foetal development has provided insight into the molecular explanation of XX maleness.
  • 3.3K
  • 13 Oct 2021
Topic Review
SO2 Poisoning Mechanism
The selective catalytic reduction (SCR) has been widely used in industrial denitrification owing to its high denitrification efficiency, low operating costs, and simple operating procedures. However, coal containing a large amount of sulfur will produce SO2 during combustion, which makes the catalyst easy to be deactivated, thus limiting the application of this technology. This review summarizes the latest NH3-SCR reaction mechanisms and the deactivation mechanism of catalyst in SO2-containing flue gas. Some strategies are summarized for enhancing the poison-resistance through modification, improvement of support, the preparation of complex oxide catalyst, optimizing the preparation methods, and acidification. The mechanism of improving sulfur resistance of catalysts at low temperatures is summarized, and the further development of the catalyst is also prospected. This paper could provide a reference and guidance for the development of SO2 resistance of the catalyst at low temperatures.
  • 3.3K
  • 09 Nov 2020
Topic Review
Cinema Therapy
Cinema therapy or movie therapy is a form of expressive therapy - like art, music and dance therapy - for medical and mental health issues. It is also used as a form of self-help. Cinema therapy was created and popularized by Dr. Gary Solomon, the first to write on using movies as therapy. The movement started to catch up again in 2019 with the featured documentary "Calypsonians" by director Anghelo Taylor, unlike the creation of Dr. Gary Solomon, Anghelo Taylor wrote the CinemaTherapy Manifesto, that starts with one simple principle "In order for cinema therapy truly exist the filmmaker must have an internal search, question or problem to solve inside himself but that relates with the rest of humanity or with specific community. Once the filmmaker and his crew engage in the process of filmmaking, they start healing by the revelation and situations that happen along the process of making a film. In the end, the result of that process will be a medicine for all the viewers as human beings. But everything starts with the deep intention that the filmmaker has when making the film"
  • 3.3K
  • 14 Feb 2026
Topic Review
Fluorescent Polymers Conspectus
The development of luminescent materials is critical to humankind. The Nobel Prizes awarded in 2008 and 2010 for research on the development of green fluorescent proteins and super-resolved fluorescence imaging are proof of this (2014). Fluorescent probes, smart polymer machines, fluorescent chemosensors, fluorescence molecular thermometers, fluorescent imaging, drug delivery carriers, and other applications make fluorescent polymers (FPs) exciting materials. 
  • 3.3K
  • 22 Mar 2022
Topic Review
Synthesis of MoS2
Molybdenum disulfide (MoS2), with a two-dimensional (2D) structure, has attracted huge research interest due to its unique electrical, optical, and physicochemical properties. MoS2 has been used as a co-catalyst for the synthesis of novel heterojunction composites with enhanced photocatalytic hydrogen production under solar light irradiation. Nanostructured MoS2 can be fabricated via both top-down and bottom-up approaches.
  • 3.3K
  • 10 Jun 2022
Topic Review
Somatic Cell Nuclear Transfer
Somatic cell nuclear transfer (SCNT) is a technique for generating embryos with genomic information identical to that of donor cells. SCNT has presented various insights into the process of de-differentiation by cellular reprogramming.  Now authors are focusing on the challenge of understanding the potential of pluripotent stem cells and the safe use. Moreover, stem cells from livestock have provided many potential to the academic field as well as medical and industrial applications.
  • 3.3K
  • 12 May 2021
Topic Review
Pentacene and Its Derivatives Deposition Methods
Pentacene is a well-known conjugated organic molecule with high mobility and a sensitive photo response. It is widely used in electronic devices, such as in organic thin-film transistors (OTFTs), organic light-emitting diodes (OLEDs), photodetectors, and smart sensors. With the development of flexible and wearable electronics, the deposition of good-quality pentacene films in large-scale organic electronics at the industrial level has drawn more research attention. Several methods are used to deposit pentacene thin films. The thermal evaporation technique is the most frequently used method for depositing thin films, as it has low contamination rates and a well-controlled deposition rate. Solution-processable methods such as spin coating, dip coating, and inkjet printing have also been widely studied because they enable large-scale deposition and low-cost fabrication of devices. 
  • 3.3K
  • 18 Apr 2022
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