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Topic Review
Role of Instagram Travel Influencers in sustainable tourism
Instagram is a critical tool for the selection of tourism destinations. Instagram travel influencers seem to play a significant role in this process, often using geo-location data to make their posts even more impactful. However, there is no evidence of them performing such a role in sustainable destinations, although these destinations are increasing and to a large extent are the future in tourism.
  • 1.8K
  • 08 Dec 2023
Topic Review
Heavy Metal Soil Contamination Detection Using Geochemistry and Field Spectroradiometry
Technological advances in hyperspectral remote sensing have been widely applied in heavy metal soil contamination studies, as they are able to provide assessments in a rapid and cost-effective way. The present work investigates the potential role of combining field and laboratory spectroradiometry with geochemical data of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) in quantifying and modelling heavy metal soil contamination (HMSC) for a floodplain site located in Wales, United Kingdom. The study objectives were to: (i) collect field- and lab-based spectra from contaminated soils by using ASD FieldSpec® 3, where the spectrum varies between 350 and 2500 nm; (ii) build field- and lab-based spectral libraries; (iii) conduct geochemical analyses of Pb, Zn, Cu and Cd using atomic absorption spectrometer; (iv) identify the specific spectral regions associated to the modelling of HMSC; and (v) develop and validate heavy metal prediction models (HMPM) for the aforementioned contaminants, by considering their spectral features and concentrations in the soil. Herein, the field- and lab-based spectral features derived from 85 soil samples were used successfully to develop two spectral libraries, which along with the concentrations of Pb, Zn, Cu and Cd were combined to build eight HMPMs using stepwise multiple linear regression. The results showed, for the first time, the feasibility to predict HMSC in a highly contaminated floodplain site by combining soil geochemistry analyses and field spectroradiometry. The generated models help for mapping heavy metal concentrations over a huge area by using space-borne hyperspectral sensors. The results further demonstrated the feasibility of combining geochemistry analyses with filed spectroradiometric data to generate models that can predict heavy metal concentrations.
  • 1.8K
  • 30 Oct 2020
Topic Review
Latency Compensated Visual-Inertial Odometry
In visual-inertial odometry (VIO), inertial measurement unit (IMU) dead reckoning acts as the dynamic model for flight vehicles while camera vision extracts information about the surrounding environment and determines features or points of interest. With these sensors, the most widely used algorithm for estimating vehicle and feature states for VIO is an extended Kalman filter (EKF). The design of the standard EKF does not inherently allow for time offsets between the timestamps of the IMU and vision data. In fact, sensor-related delays that arise in various realistic conditions are at least partially unknown parameters. A lack of compensation for unknown parameters often leads to a serious impact on the accuracy of VIO systems and systems like them. To compensate for the uncertainties of the unknown time delays, this study incorporates parameter estimation into feature initialization and state estimation. Moreover, computing cross-covariance and estimating delays in online temporal calibration correct residual, Jacobian, and covariance. Results from flight dataset testing validate the improved accuracy of VIO employing latency compensated filtering frameworks. The insights and methods proposed here are ultimately useful in any estimation problem (e.g., multi-sensor fusion scenarios) where compensation for partially unknown time delays can enhance performance.
  • 1.8K
  • 29 Apr 2021
Topic Review
Druggable genetic alterations in NSCLC
Lung cancer is the leading cause of death for malignancy worldwide. Its molecular profiling has enriched our understanding of cancer initiation and progression and has become fundamental to provide guidance on treatment with targeted therapies. Testing the presence of driver mutations in specific genes in lung tumors has thus radically changed the clinical management and outcomes of the disease. Numerous studies performed with traditional sequencing methods have investigated the occurrence of such mutations in lung cancer, and new insights regarding their frequency and clinical significance are continuously provided with the use of last generation sequencing technologies.
  • 1.8K
  • 15 Jan 2021
Topic Review
Deep and Meaningful E-Learning
Deep and meaningful e-learning should be an essential outcome of quality education.
  • 1.8K
  • 25 Mar 2021
Topic Review
Machine Learning in Intraoperative Neurophysiological Monitoring
Intraoperative neurophysiological monitoring (IONM) is being applied to a wide range of surgical fields as a diagnostic tool to protect patients from neural injuries that may occur during surgery. However, several contributing factors complicate the interpretation of IONM, and it is labor- and training-intensive. Meanwhile, machine learning (ML)-based medical research has been growing rapidly, and many studies on the clinical application of ML algorithms have been published.
  • 1.8K
  • 24 Aug 2022
Topic Review
Scanning Kelvin Probe
In microscopy, a scanning Kelvin probe (SKP) is a non-contact, non-destructive scanning probe microscopy (SPM) technique used to measure the work function of the sample under study. By raster scanning in the x,y plane the work function of the sample can be locally mapped for correlation with sample features. It is predominantly used to measure corrosion and coatings. It is closely related to the Kelvin probe force microscope (KPFM) technique.
  • 1.8K
  • 30 Oct 2022
Topic Review
Photometry
Photometry, from Greek photo- ("light") and -metry ("measure"), is a technique used in astronomy that is concerned with measuring the flux or intensity of light radiated by astronomical objects. This light is measured through a telescope using a photometer, often made using electronic devices such as a CCD photometer or a photoelectric photometer that converts light into an electric current by the photoelectric effect. When calibrated against standard stars (or other light sources) of known intensity and colour, photometers can measure the brightness or apparent magnitude of celestial objects. The methods used to perform photometry depend on the wavelength region under study. At its most basic, photometry is conducted by gathering light and passing it through specialized photometric optical bandpass filters, and then capturing and recording the light energy with a photosensitive instrument. Standard sets of passbands (called a photometric system) are defined to allow accurate comparison of observations. A more advanced technique is spectrophotometry that is measured with a spectrophotometer and observes both the amount of radiation and its detailed spectral distribution. Photometry is also used in the observation of variable stars, by various techniques such as, differential photometry that simultaneously measures the brightness of a target object and nearby stars in the starfield or relative photometry by comparing the brightness of the target object to stars with known fixed magnitudes. Using multiple bandpass filters with relative photometry is termed absolute photometry. A plot of magnitude against time produces a light curve, yielding considerable information about the physical process causing the brightness changes. Precision photoelectric photometers can measure starlight around 0.001 magnitude. The technique of surface photometry can also be used with extended objects like planets, comets, nebulae or galaxies that measures the apparent magnitude in terms of magnitudes per square arcsecond. Knowing the area of the object and the average intensity of light across the astronomical object determines the surface brightness in terms of magnitudes per square arcsecond, while integrating the total light of the extended object can then calculate brightness in terms of its total magnitude, energy output or luminosity per unit surface area.
  • 1.8K
  • 11 Nov 2022
Biography
John C. Baez
John Carlos Baez (/ˈbaɪɛz/; born June 12, 1961) is an American mathematical physicist and a professor of mathematics at the University of California, Riverside (UCR)[1] in Riverside, California. He has worked on spin foams in loop quantum gravity, applications of higher categories to physics, and applied category theory. Baez is also the author of This Week's Finds in Mathematical Physics,[2
  • 1.8K
  • 25 Nov 2022
Topic Review
Ionic Liquids for CO2 Capture
Ionic Liquids (ILs) are the molten salts with a melting point lower than 100 °C and behave as a liquid at room temperature. ILs properties can be altered by the careful selection of the anion and cation. ILs have bulky organic cations with low molecular symmetry and small organic/inorganic anions that are in their molten form in their pure states under ambient conditions. Global warming is one of the major problems in the developing world, and one of the major causes of global warming is the generation of carbon dioxide (CO2) because of the burning of fossil fuels. Burning fossil fuels to meet the energy demand of households and industries is unavoidable. The current commercial and experimental techniques used for capturing and storing CO2 have serious operational and environmental constraints. The amine-based absorption technique for CO2 capture has a low absorption and desorption ratio, and the volatile and corrosive nature of the solvent further complicates the situation. To overcome all of these problems, researchers have used ionic liquids (ILs) and deep eutectic solvents (DESs) as a replacement for commercial amine-based solvents. ILs and DESs are tunable solvents that have a very low vapor pressure, thus making them an ideal medium for CO2 capture. Moreover, most ILs and DESs have low toxicity and can be recycled without a significant loss in their CO2 capture capability.
  • 1.8K
  • 23 Dec 2022
Topic Review
Antifungals Used in Exotic Avian and Reptile Species
Exotic animals are typically non-domesticated and non-indigenous to the geographical region they inhabit. Fungal diseases are widespread and have led to the decline of multifarious exotic animals. Fatal dermatomycoses caused by Nannizziopsis spp. have been reported in captive reptiles, despite treatment with antifungals. Dermatomycoses such as those caused by the fungal complex Chrysosporium anamorph of Nannizziopsis vriesii (CANV) are emerging infectious diseases in reptiles, with increasing prevalence and spread across geographical regions and, unfortunately, increasing antifungal resistance patterns. Likewise, the most common fungal disease in avians, aspergillosis, has a high mortality rate. 
  • 1.8K
  • 10 Aug 2023
Topic Review
Vascular Endothelial Glycocalyx
Vascular endothelial cells are a monolayer of cells that comprise the innermost layer of cells in the vascular system, including arteries, veins, and capillaries, and serve a barrier function for the blood vessels surrounding all organs and in direct contact with the blood flowing through the vascular lumen.
  • 1.8K
  • 30 Dec 2020
Topic Review
China Automotive Firms' Efficiency Evaluation
DEA (Data Envelopment Analysis), as a methodology for the efficiency evaluation of Decision-Making Units (DMUs) with multiple inputs and outputs, is widely used in various areas. The basic idea of DEA is to fit a non-parametric efficient production frontier with DMUs and measure the efficiency relative to the best-performance observations in the sample. In this paper, the China’s listed firms in the automotive industry are seen as the DMUs, and our goal is to measure the efficiency of each DMU and identity the ones that use the inputs more efficiently than the others that have resources over-utilized, namely, the firms can reduce the inputs while the outputs remains constant (input-oriented) rather than the firms can increase the outputs while their inputs remains constant (output-oriented). Therefore, the input-oriented model of DEA is appropriate for our research.
  • 1.8K
  • 06 Mar 2021
Topic Review
Cardiovascular Diseases and Stem Cells
This entry provides an update on previous and current research in the field of Cardiovascular diseases (CVDs), a class of disorders affecting the heart or blood vessels. Despite progress in clinical research and therapy, CVDs still represent the leading cause of mortality and morbidity worldwide. The hallmarks of cardiac diseases include inflammation, fibrosis, scar tissue, hyperplasia, hypertrophy, abnormal ventricular remodeling, and cardiomyocyte death, which is an irreversible process that induces heart failure with progressive and dramatic consequences. Both genetic and environmental factors pathologically contribute to the development of CVDs, but the precise causes that trigger cardiac diseases and their progression are still largely unknown. In this scenario, the possibility to generate patient-specific cardiac cells from induced pluripotent stem cells (iPSCs) represents a powerful platform for the investigation of these life-threatening disorders.
  • 1.8K
  • 26 Oct 2020
Topic Review
Design of Sustainable Flexible Pavement
The conventional methodologies for the design of flexible pavements are not adequate in providing solutions that meet the diverse sustainability challenges. Therefore, developing new methodologies and frameworks for the design of flexible pavement has become a priority for most highway agencies. On the other hand, there is no sound sustainable flexible pavement framework at the design phase that considers the key engineering performance, environmental impact, and economic benefits of sustainability metrics. Hence, premature failure of flexible pavements has become a common problem leading to a growing demand for sustainable pavement. Pavement engineers need to have access to tools that permit them to design flexible pavements capable of providing sustainable solutions under various complex scenarios and uncertainties.
  • 1.8K
  • 10 Jan 2022
Topic Review
Near-Infrared Spectroscopy Coupled to Hyperspectral Imaging
Near-infrared (800–2500 nm; NIR) spectroscopy coupled to hyperspectral imaging (NIR-HSI) has greatly enhanced its capability and thus widened its application and use across various industries. This non-destructive technique that is sensitive to both physical and chemical attributes of virtually any material can be used for both qualitative and quantitative analyses.
  • 1.8K
  • 18 Mar 2022
Topic Review
Laxogenin C
Laxogenin C (LGC) is a natural spirostanol deriving from plant hormone which has shown anti-inflammatory, antibacterial, and growth-regulating activities.
  • 1.8K
  • 12 Apr 2022
Topic Review
The Effect of Perceptions on Tourism
Today, tourism plays an important role in the economic and financial development of countries, and its impact is greater than ever. Therefore, for sustainable economic and financial growth and well-planned development, public and private investments should be directed to areas of priority tourism development. 
  • 1.8K
  • 12 Jul 2022
Topic Review
Subsea Power Cable Health Management
Subsea power cables are critical assets for electrical transmission and distribution networks, and highly relevant to regional, national, and international energy security and decarbonization given the growth in offshore renewable energy generation. Existing condition monitoring techniques are restricted to highly constrained online monitoring systems that only prioritize internal failure modes, representing only 30% of cable failure mechanisms, and has limited capacity to provide precursor indicators of such failures or damages.
  • 1.8K
  • 13 Sep 2023
Topic Review
Biostimulants in Plant
Adverse environmental conditions due to climate change, combined with declining soil fertility, threaten food security. Modern agriculture is facing a pressing situation where novel strategies must be developed for sustainable food production and security. Biostimulants, conceptually defined as non-nutrient substances or microorganisms with the ability to promote plant growth and health, represent the potential to provide sustainable and economically favorable solutions that could introduce novel approaches to improve agricultural practices and crop productivity. Current knowledge and phenotypic observations suggest that biostimulants potentially function in regulating and modifying physiological processes in plants to promote growth, alleviate stresses, and improve quality and yield. 
  • 1.8K
  • 23 Jan 2021
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