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Topic Review
Soling
The Soling is an International open keelboat class designed by Jan Linge from Norway in 1965. In 1968, it was selected to be an Olympic class for the Games of the XX Olympiad in Kiel 1972 (GER). The Soling maintained this status until her final appearance at the 2000 Olympics. The Soling is a strong boat designed for any wind and sea condition. The boats are one-design originating from an authorized single plug and mould and made of glass reinforced polyester, making competition as equal as possible. The lifetime of a Soling is long. Those produced in the early days are still in competition (more than 50 years after being built). At the 2019 North American Championship the 5th place was taken by a German team (GER 1) sailing a refurbished Soling build in 1968. Characteristic for the Soling is the droop-hiking technique. Since 2008, the Soling is one of the Vintage Yachting Classes at the Vintage Yachting Games.
  • 1.8K
  • 03 Nov 2022
Topic Review
Oral Glucose Tolerance Test
The oral glucose tolerance test (OGTT) has been the mainstay for diagnosing gestational diabetes for decades. However, this test is cumbersome, deeply flawed, and has reduced reproducibility. In this review, we explore a history of the OGTT, its reproducibility, and the many factors that can impact its results with an emphasis on pregnancy.
  • 1.8K
  • 02 Feb 2021
Topic Review
Scour Protections Design Optimization
The offshore wind is the sector of marine renewable energy with the highest commercial development at present. The margin to optimise offshore wind foundations is considerable, thus attracting both the scientific and the industrial community. Due to the complexity of the marine environment, the foundation of an offshore wind turbine represents a considerable portion of the overall investment. An important part of the foundation’s costs relates to the scour protections, which prevent scour effects that can lead the structure to reach the ultimate and service limit states. Presently, the advances in scour protections design and its optimisation for marine envi-ronments face many challenges, and the latest findings are often bounded by stakeholder’s strict confidential policies.
  • 1.8K
  • 23 Mar 2021
Topic Review
Dietary Management of Chronic Diarrhoea
Chronic diarrhoea affects up to 14% of adults, it impacts on quality of life and its cause can be variable. Patients with chronic diarrhoea are presented with a plethora of dietary recommendations, often sought from the internet or provided by those who are untrained or inexperienced. Once a diagnosis is made, or serious diagnoses are excluded, dietitians play a key role in the management of chronic diarrhoea. The dietitian’s role varies depending on the underlying cause of the diarrhoea, with a wide range of dietary therapies available. Dietitians also have an important role in educating patients about the perils and pitfalls of dietary therapy.
  • 1.8K
  • 29 Apr 2021
Topic Review
Copper-Catalyzed Intramolecular Borylative Coupling with Imines
Copper-catalyzed enantioselective borylative cyclization with various electrophiles via difunctionalization of unsaturated hydrocarbons is a powerful tool for the generation of interesting boron-containing carbocycles and heterocycles processes involving a chiral organocopper intermediate. Alkenes, allenes, and alkynes are versatile and easily accessible substrates that can be subjected to a wide range of reactions to produce densely functionalized, enantioenriched products.
  • 1.8K
  • 17 Jul 2022
Topic Review
The Biological Activities of Marine Exopolysaccharides
The unique living environment of marine microorganisms endows them with the potential to produce novel compounds with diverse biological activities. Exopolysaccharide (EPS) is a high molecular weight carbohydrate polymer secreted by microorganisms during growth and metabolism. The complex and diverse structures of EPS endow them with unique biological activities and functions. 
  • 1.8K
  • 23 Aug 2022
Topic Review
Curcumin
Natural products have been used in medicine for thousands of years, in the recent times they gained a significant popularity globally due to their potential health benefits. Phytochemicals regulate differential gene expression to modulate various cellular pathways implicated in cellular protection. Curcumin is a natural dietary polyphenol extracted from Curcuma Longa L. with different biological and pharmacological effects. One of the important targets of curcumin is TLR-4, the receptor which plays a key role in the modulation of the immune responses and stimulate the production of inflammatory chemokines and cytokines. Different studies have demonstrated that curcumin attenuates inflammatory response via TLR-4 acting directly on receptor, or by its downstream pathway. Curcumin bioavailability is low, so the use of exosomes, as nano drug delivery, could improve the efficacy of curcumin in inflammatory diseases. The focus of this review is to explore the therapeutic effect of curcumin interacting with TLR-4 receptor and how this modulation could improve the prognosis of neuroinflammatory and rheumatic diseases.
  • 1.8K
  • 08 Nov 2021
Topic Review
Obliterative Bronchiolitis
Obliterative bronchiolitis (OB), also known as constrictive bronchiolitis and popcorn lung, is a disease that results in obstruction of the smallest airways of the lungs (bronchioles) due to inflammation. Symptoms include a dry cough, shortness of breath, wheezing and feeling tired. These symptoms generally get worse over weeks to months. It is not related to cryptogenic organizing pneumonia, previously known as bronchiolitis obliterans organizing pneumonia. Causes include breathing in toxic fumes, respiratory infections, connective tissue disorder or complications following a bone marrow or heart-lung transplant. Symptoms may not occur until two to eight weeks following toxic exposure or infection. The underlying mechanism involves inflammation that results in scar tissue formation. Diagnosis is by CT scan, pulmonary function tests or lung biopsy. A chest X-ray is often normal. While the disease is not reversible, treatments can slow further worsening. This may include the use of corticosteroids or immunosuppressive medication. A lung transplant may be offered. Outcomes are often poor, with most people dying in months to years. Obliterative bronchiolitis is rare in the general population. It, however, affects about 75% of people by ten years following a lung transplant and up to 10% of people who have received a bone marrow transplant from someone else. The condition was first clearly described in 1981. Prior descriptions occurred as early as 1956, with the term "bronchiolitis obliterans" used first by Reynaud in 1835.
  • 1.8K
  • 03 Nov 2022
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
Pseudorabies Virus
Pseudorabies, or Aujeszky’s disease, is a notifiable worldwide infection of domestic and feral swine that causes economic losses for the swine industry. In domestic pigs, the virus is responsible for nervous and/or respiratory symptoms; in pregnant sows, it is one of the major causes of stillbirth, mummification, embryonic death, and infertility (SMEDI). It is known that PRV infection in wild boar is associated with low pathogenicity and attenuated or absent symptomatology, but limited information is available about the ability of the virus to infect the foetuses of infected wild boar pregnant sows. Due to scarce information about the reproductive consequences, we investigate the possible intrauterine vertical transmission of the virus in wild boar pregnant sow living in a highly infected area. A number of 54 hunted wild boar were sampled during 2018–2019, and blood, genital and nasal swabs, placenta, and fetuses were collected for serological and molecular investigations. A seroprevalence of 74% (40/54) was detected, while 1/24 pregnant sow and 1/24 pooled foetuses tested positive by PCR (gene gB). This is the first evidence of viral detection in foetuses from seropositive pregnant wild boar. This finding suggests the possible pathogenetic role of PRV on pregnancy in wild boar and the existence of an additional transmission route.
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  • 28 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
Quorum Sensing Regulation
Quorum sensing is a type of chemical communication by which bacterial populations control expression of their genes in a coordinated manner. This regulatory mechanism is commonly used by pathogens to control the expression of genes encoding virulence factors and that of genes involved in the bacterial adaptation to variations in environmental conditions. In phytopathogenic bacteria, several mechanisms of quorum sensing have been characterized. In this review, we describe the different quorum sensing systems present in phytopathogenic bacteria, such as those using the signal molecules named N-acyl-homoserine lactone (AHL), diffusible signal factor (DSF), and the unknown signal molecule of the virulence factor modulating (VFM) system. We focus on studies performed on phytopathogenic bacteria of major importance, including Pseudomonas, Ralstonia, Agrobacterium, Xanthomonas, Erwinia, Xylella,Dickeya, and Pectobacterium spp. For each system, we present the mechanism of regulation, the functions targeted by the quorum sensing system, and the mechanisms by which quorum sensing is regulated.
  • 1.8K
  • 05 Mar 2021
Topic Review
Polymyxins–Curcumin Combination Antimicrobial Therapy
The emergence of antimicrobial resistance in Gram-negative bacteria poses a huge health challenge. The therapeutic use of polymyxins (i.e., colistin and polymyxin B) is commonplace due to high efficacy and limiting treatment options for multidrug-resistant Gram-negative bacterial infections. Nephrotoxicity and neurotoxicity are the major dose-limiting factors that limit the therapeutic window of polymyxins; nephrotoxicity is a complication in up to ~60% of patients. The emergence of polymyxin-resistant strains or polymyxin heteroresistance is also a limiting factor. These caveats have catalyzed the search for polymyxin combinations that synergistically kill polymyxin-susceptible and resistant organisms and/or minimize the unwanted side effects. Curcumin—an FDA-approved natural product—exerts many pharmacological activities. Recent studies showed that polymyxins–curcumin combinations showed a synergistically inhibitory effect on the growth of bacteria (e.g., Gram-positive and Gram-negative bacteria) in vitro. Moreover, curcumin co-administration ameliorated colistin-induced nephrotoxicity and neurotoxicity by inhibiting oxidative stress, mitochondrial dysfunction, inflammation and apoptosis.
  • 1.8K
  • 28 May 2021
Topic Review
Canadian Goldenrod
Perennial herb Solidago canadensis L. (Asteraceae: Astereae), originating in North America, was brought and introduced into middle Europe as an ornamental, schizanthus, and melliferous plant in the middle of the 18th century. In the end, it unintentionally spread from the gardens to the natural environment. 
  • 1.8K
  • 04 Mar 2022
Topic Review
Wetland Resources in South Africa
Wetlands are important ecosystems with physical and socioeconomic benefits. A wetland is defined as an area of soil covered with water or has water close to its surface all year or at some periods of the year. They are necessary for people’s livelihoods but not usually considered important.
  • 1.8K
  • 13 Jun 2022
Topic Review
Functional Materials for Wearable Sensors
With the recent development of flexible electronic materials, smart transducers, and wireless systems, wearable sensor technology has gained significant interest in the realization of personalized medical care. The design and development of flexible/stretchable dry electrodes with good adherence to biological tissues is in great demand due to the complex attributes of the human body. However, the major difficulty is finding the appropriate materials with good flexibility and conductivity, although some other relevant features such as bio-compatibility, durability, weight, size, etc.
  • 1.8K
  • 05 Sep 2022
Topic Review
Geologic Modelling
Geologic modelling, geological modelling or geomodelling is the applied science of creating computerized representations of portions of the Earth's crust based on geophysical and geological observations made on and below the Earth surface. A geomodel is the numerical equivalent of a three-dimensional geological map complemented by a description of physical quantities in the domain of interest. Geomodelling is related to the concept of Shared Earth Model; which is a multidisciplinary, interoperable and updatable knowledge base about the subsurface. Geomodelling is commonly used for managing natural resources, identifying natural hazards, and quantifying geological processes, with main applications to oil and gas fields, groundwater aquifers and ore deposits. For example, in the oil and gas industry, realistic geologic models are required as input to reservoir simulator programs, which predict the behavior of the rocks under various hydrocarbon recovery scenarios. A reservoir can only be developed and produced once; therefore, making a mistake by selecting a site with poor conditions for development is tragic and wasteful. Using geological models and reservoir simulation allows reservoir engineers to identify which recovery options offer the safest and most economic, efficient, and effective development plan for a particular reservoir. Geologic modelling is a relatively recent subdiscipline of geology which integrates structural geology, sedimentology, stratigraphy, paleoclimatology, and diagenesis; In 2-dimensions (2D), a geologic formation or unit is represented by a polygon, which can be bounded by faults, unconformities or by its lateral extent, or crop. In geological models a geological unit is bounded by 3-dimensional (3D) triangulated or gridded surfaces. The equivalent to the mapped polygon is the fully enclosed geological unit, using a triangulated mesh. For the purpose of property or fluid modelling these volumes can be separated further into an array of cells, often referred to as voxels (volumetric elements). These 3D grids are the equivalent to 2D grids used to express properties of single surfaces. Geomodelling generally involves the following steps:
  • 1.8K
  • 06 Oct 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
Diversity (Business)
The business case for diversity stems from the progression of the models of diversity within the workplace since the 1960s. In the United States, the original model for diversity was situated around affirmative action drawing from equal opportunity employment objectives implemented in the Civil Rights Act of 1964. Equal employment opportunity was centered around the idea that any individual academically or physically qualified for a specific job could strive for (and possibly succeed) at obtaining the said job without being discriminated against based on identity. This compliance-based model gave rise to the idea that tokenism was the reason an individual was hired into a company when they differed from the dominant group. Dissatisfaction from minority groups eventually altered and/or raised the desire to achieve perfect employment opportunities in every job. The social justice model evolved next and extended the idea that individuals outside the dominant group should be given opportunities within the workplace, not only because it was instituted as a law, but because it was the right thing to do. Kevin Sullivan an ex-vice president of Apple Inc. said that "diversity initiatives must be sold as business, not social work." This model still revolved around the idea of tokenism, but it also brought in the notion of hiring based on a "good fit".In the deficit model, it is believed that organizations that do not have a strong diversity inclusion culture will invite lower productivity, higher absenteeism, and higher turnover which will result in higher costs to the company. Establishments with more diversity are less likely to have successful unionization attempts.
  • 1.8K
  • 02 Nov 2022
Topic Review
Bose–Hubbard Model
The Bose–Hubbard model gives a description of the physics of interacting spinless bosons on a lattice. It is closely related to the Hubbard model which originated in solid-state physics as an approximate description of superconducting systems and the motion of electrons between the atoms of a crystalline solid. The model was first introduced by Gersch and Knollman in 1963 in the context of granular superconductors. (The term 'Bose' in its name refers to the fact that the particles in the system are bosonic.) The model rose to prominence in the 1980s after it was found to capture the essence of the superfluid-insulator transition in a way that was much more mathematically tractable than fermionic metal-insulator models. The Bose–Hubbard model can be used to describe physical systems such as bosonic atoms in an optical lattice, as well as certain magnetic insulators. Furthermore, it can also be generalized and applied to Bose–Fermi mixtures, in which case the corresponding Hamiltonian is called the Bose–Fermi–Hubbard Hamiltonian.
  • 1.8K
  • 10 Nov 2022
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