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Topic Review
Microbiological Hazards in Dairy
In Africa, milk production, processing and consumption are integral part of the traditional food supply, with dairy products being a staple component of recommended healthy diets. In this article, we highlight the main microbial food safety hazards in the dairy chain in African. These include risk factors associated with various steps in the dairy chain including primary production, milk collection, storage, packaging, transportation and distribution, traditional milk processing as well as consumer practices.
  • 2.4K
  • 28 Oct 2020
Topic Review
Dream Chronicles
Dream Chronicles, originally titled Dream Chronicles: The Endless Slumber, is an adventure, hidden object, and puzzle casual game developed by KatGames and published by PlayFirst. It is the first installment in the series. Set in a mystical world where mortal and fairy realms collide, the game tells the story of a mortal woman named Faye who is the only being able to awaken from a powerful fairy's dream spell. She embarks on an adventure through a dream world to find her fairy husband and save her hometown. To solve the mystery, players must complete puzzles and search for clues leading to the whereabouts of Faye's husband. As the first part of the first trilogy, Dream Chronicles spawned two direct sequels, Dream Chronicles 2 and Dream Chronicles, which were released in 2008 and 2009 respectively.
  • 2.4K
  • 12 Oct 2022
Topic Review
Multispectral Image
Multispectral imaging captures image data within specific wavelength ranges across the electromagnetic spectrum. The wavelengths may be separated by filters or detected with the use of instruments that are sensitive to particular wavelengths, including light from frequencies beyond the visible light range, i.e. infrared and ultra-violet. Spectral imaging can allow extraction of additional information the human eye fails to capture with its visible receptors for red, green and blue. It was originally developed for military target identification and reconnaissance. Early space-based imaging platforms incorporated multispectral imaging technology to map details of the Earth related to coastal boundaries, vegetation, and landforms. Multispectral imaging has also found use in document and painting analysis. Multispectral imaging measures light in a small number (typically 3 to 15) of spectral bands. Hyperspectral imaging is a special case of spectral imaging where often hundreds of contiguous spectral bands are available.
  • 2.4K
  • 21 Oct 2022
Topic Review
Venus (Planet)
Venus is the second-closest planet to the Sun, orbiting it every 224.7 Earth days. After Earth's Moon, it is the brightest object in the night sky, reaching an apparent magnitude of −4.6. As an inferior planet from Earth it never appears to venture far from the Sun, and its elongation reaches a maximum of 47.8°. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset, and is often referred to as the Morning Star or as the Evening Star. A terrestrial planet, it is sometimes called Earth's "sister planet", as the two are similar in size and bulk composition. The planet is covered with an opaque layer of highly reflective clouds and its surface cannot be seen from space in visible light, making it a subject of great speculation until some of its secrets were revealed by planetary science in the 20th century. Venus has the densest atmosphere of the terrestrial planets, consisting mostly of carbon dioxide, and the atmospheric pressure at the planet's surface is 90 times that of the Earth. Venus' surface has been mapped in detail only in the last 20 years. It shows evidence of extensive volcanism, and some of its volcanoes may still be active today. In contrast to the constant crustal movement seen on Earth, Venus is thought to undergo periodic episodes of plate tectonics, in which the crust is subducted rapidly within a few million years separated by stable periods of a few hundred million years. The planet is named after Venus, the Roman goddess of love, and most of its surface features are named after famous and mythological women. The adjective Venusian is commonly used for items related to Venus, though the Latin adjective is the rarely used Venereal; the now-archaic Cytherean is still occasionally encountered.
  • 2.4K
  • 01 Nov 2022
Topic Review
Prostate-Specific Membrane Antigen
Prostate-specific membrane antigen (PSMA) is a transmembrane protein that is overexpressed in prostate cancer and correlates with the aggressiveness of the disease. PSMA is a promising target for positron emission tomography (PET) imaging and theranostics in prostate cancer patients validated in recent prospective trials. Several clinical trials are currently ongoing to define the role of PSMA targeting radioligands in different settings and to evaluate the potential of other PSMA-based therapeutic modalities in prostate cancer.
  • 2.4K
  • 11 May 2021
Topic Review
Ras-Associated Protein 1 in Cancer
Metastasis is known as the most life-threatening event in cancer patients. In principle, the immune system can prevent tumor development. However, dysfunctional T cells may fail to eliminate the tumor cells effectively and provide additional survival advantages for tumor proliferation and metastasis. Constitutive activation of Ras-associated protein1 (Rap1) has not only led to T cell anergy, but also inhibited autophagy and supported cancer progression through various oncogenic events. Inhibition of Rap1 activity with its negative regulator, Rap1GAP, impairs tumor progression. However, active Rap1 reduces tumor invasion in some cancers, indicating that the pleiotropic effects of Rap1 signaling in cancers could be cancer-specific. All in all, targeting Rap1 signaling and its regulators could potentially control carcinogenesis, metastasis, chemoresistance and immune evasion. Rap1GAP could be a promising therapeutic target in combating cancer. 
  • 2.4K
  • 23 Sep 2020
Topic Review
Bacillus Species and Heavy Metals
 Heavy metals are one of the major pollutants that contribute to the escalating problem of environmental pollution, being primarily introduced in sensitive ecological habitats through industrial effluents, wastewater, as well as sewage of various industries. Microbial bioremediation, particularly the use of bacteria, has gained attention due to the feasibility and efficiency of using them in removing heavy metals from contaminated environments. Bacteria have several methods of processing heavy metals through general resistance mechanisms, biosorption, adsorption, and efflux mechanisms. Bacillus spp. are model Gram-positive bacteria that have been studied extensively for their biosorption abilities and molecular mechanisms that enable their survival as well as their ability to remove and detoxify heavy metals.
  • 2.4K
  • 09 Aug 2021
Topic Review
Bioethanol Production of Distillery Stillage
Distillery stillage has a high energy potential (13.6 MJ/kg TS, 10.4 MJ/kg COD), which indicates that it can be processed via anaerobic digestion and is a suitable substrate for conversion into energy.
  • 2.4K
  • 16 Nov 2021
Topic Review
COROT-7b
COROT-7b (previously named COROT-Exo-7b) is an exoplanet orbiting around the star COROT-7, in the constellation Monoceros, at 489 light years from Earth. It was first detected photometrically by the French-led COROT mission and reported in February 2009. Until the announcement of Kepler-10b in January 2011, it was the smallest exoplanet to have its diameter measured, at 1.58 times that of the Earth (which would give it a volume 3.95 times Earth's), and the first potential extrasolar terrestrial planet to be found. The planet has a very short orbital period, revolving around its host star in about 20 hours. Combination of the planet's diameter derived from transit data with the planet's mass derived from radial velocity measurements, meant that the density of CoRoT-7b was about the same as that of Earth and, therefore, that CoRoT-7b was made of rock like Earth and was not a gas giant like Jupiter. The radial velocity observations of CoRoT-7 also detected a second super-Earth, CoRoT-7c, which has a mass 8.4 times that of Earth and orbits every 3.7 days at a distance of 6.9 million km (4.3 million miles).
  • 2.4K
  • 19 Oct 2022
Topic Review
The Quest of the Historical Jesus
The Quest of the Historical Jesus (German: Geschichte der Leben-Jesu-Forschung, literally "History of Life-of-Jesus Research") is a 1906 work of Biblical historical criticism written by Albert Schweitzer during the previous year, before he began to study for a medical degree. The original edition was translated into English by William Montgomery and published in 1910. An expanded second German edition was published during 1913, containing theologically significant revisions and expansions. This expanded edition was not published in English until 2001.
  • 2.4K
  • 03 Nov 2022
Topic Review
Cappadocia (Roman Province)
Template:Infobox Former Subdivision Cappadocia was a province of the Roman Empire in Anatolia (modern central-eastern Turkey), with its capital at Caesarea. It was established in 17 AD by the Emperor Tiberius (ruled 14-37 AD), following the death of Cappadocia's last king, Archelaus. Cappadocia was an imperial province, meaning that its governor (legatus Augusti) was directly appointed by the emperor. During the latter 1st century, the province also incorporated the regions of Pontus and Armenia Minor.
  • 2.4K
  • 08 Nov 2022
Topic Review
Sustainable Total Productive Maintenance
Sustainable Total Productive Maintenance (STPM) arose in 2021 as a promising, new concept to fill the lack of sustainability in Total Productive Maintenance (TPM) and allow companies to overcome its implementation barriers. It revolves around increasing the understanding of the systems approach and contributing to setting contemporary companies’ sustainable ideology by supporting orientation toward sustainability from a sustainable maintenance perspective. However, STPM is still in its infancy and is viewed as a complement to the traditional TPM approach and is based on its pillars. 
  • 2.4K
  • 18 Sep 2023
Topic Review
Determining Number of Clusters in a Data Set
For a certain class of clustering algorithms (in particular k-means, k-medoids and expectation–maximization algorithm), there is a parameter commonly referred to as k that specifies the number of clusters to detect. Other algorithms such as DBSCAN and OPTICS algorithm do not require the specification of this parameter; hierarchical clustering avoids the problem altogether. The correct choice of k is often ambiguous, with interpretations depending on the shape and scale of the distribution of points in a data set and the desired clustering resolution of the user. In addition, increasing k without penalty will always reduce the amount of error in the resulting clustering, to the extreme case of zero error if each data point is considered its own cluster (i.e., when k equals the number of data points, n). Intuitively then, the optimal choice of k will strike a balance between maximum compression of the data using a single cluster, and maximum accuracy by assigning each data point to its own cluster. If an appropriate value of k is not apparent from prior knowledge of the properties of the data set, it must be chosen somehow. There are several categories of methods for making this decision.
  • 2.4K
  • 22 Nov 2022
Topic Review
Membrane Processes for Microplastic Removal
The world plastic production is constantly growing, with production rising from 335 million tons in 2016 to 348 million tons in 2017. The significant and continuous increase in the production of plastics causes an enormous amount of plastic waste on the land entering the aquatic environment. Furthermore, wastewater treatment plants (WWTPs) are reported as the main source of microplastic and nanoplastic in the effluents, since they are not properly designed for this purpose. Among the tertiary treatment processes, membrane operations can offer an effective solution to the microplastic and nanoplastic pollution in the effluents.
  • 2.4K
  • 24 Dec 2021
Topic Review
Exploring Coastal Access in South Africa
Coastal spaces have been highly contested terrains in South Africa, dating from the colonial period to the present time. Inclusive documentation of the history of coastal access in South Africa is inadequate. The alienation of the African majority from coastal access in South Africa has been systematically executed through various legislations. Although 1994 (democratic era) ushered in a political change, coastal spaces in South Africa still reflect historical racial divide, with former Caucasian areas well-endowed with facilities whilst others are still underdeveloped. The lack of access to coastal resources remains a challenge to many previously disadvantaged communities, owing to South Africa’s history of Apartheid. Apartheid spatial planning remains a factor that undermines equitable access to the coast.
  • 2.4K
  • 07 Apr 2022
Topic Review
Lactobacillus Vaccine
Lactobacillus vaccines are used in the therapy and prophylaxis of non-specific bacterial vaginitis and trichomoniasis. The vaccines consist of specific inactivated strains of Lactobacilli, called "aberrant" strains in the relevant literature dating from the 1980s. These strains were isolated from the vaginal secretions of patients with acute colpitis. The lactobacilli in question are polymorphic, often shortened or coccoid in shape and do not produce an acidic, anti-pathogenic vaginal environment. A colonization with aberrant lactobacilli has been associated with an increased susceptibility to vaginal infections and a high rate of relapse following antimicrobial treatment. Intramuscular administration of inactivated aberrant lactobacilli provokes a humoral immune response. The production of specific antibodies both in serum and in the vaginal secretion has been demonstrated. As a result of the immune stimulation, the abnormal lactobacilli are inhibited, the population of normal, rod-shaped lactobacilli can grow and exert its defense functions against pathogenic microorganisms.
  • 2.4K
  • 17 Oct 2022
Topic Review
Japanese Zen
Zen is the Japanese variant of Chan Buddhism, a Mahayana school that strongly emphasizes dhyana concentration-meditation. This practice, according to Zen proponents, gives insight into one's true nature, or the emptiness of inherent existence, which opens the way to a liberated way of living.
  • 2.4K
  • 04 Nov 2022
Topic Review
Derealization
Derealization is an alteration in the perception of the external world, causing sufferers to perceive it as unreal, distant, distorted or falsified. Other symptoms include feeling as if one's environment is lacking in spontaneity, emotional coloring, and depth. It is a dissociative symptom that may appear in moments of severe stress. Derealization is a subjective experience pertaining to a person's perception of the outside world, while depersonalization is a related symptom characterized by dissociation towards one's own body and mental processes. The two are commonly experienced in conjunction with one another, but are also known to occur independently. Chronic derealization is fairly rare, and may be caused by occipital–temporal dysfunction. Experiencing derealization for long periods of time or having recurring episodes can be indicative of many psychological disorders, and can cause significant distress among sufferers. However, temporary derealization symptoms are commonly experienced by the general population a few times throughout their lives, with a lifetime prevalence of up to 26-74% and a prevalence of 31–66% at the time of a traumatic event.
  • 2.4K
  • 29 Nov 2022
Topic Review
GNSS Positioning Calculation
The global navigation satellite system (GNSS) positioning for receiver's position is derived through the calculation steps, or algorithm, given below. In essence, a GNSS receiver measures the transmitting time of GNSS signals emitted from four or more GNSS satellites (giving the pseudorange) and these measurements are used to obtain its position (i.e., spatial coordinates) and reception time.
  • 2.4K
  • 05 Dec 2022
Topic Review
Defining Infidelity
The experience of infidelity can be a traumatic affair that ruptures an individual's expectation of their most significant person. Its impact can cause significant emotional, psychological, and cognitive dysfunction for all parties involved. And although its definition is fluid, infidelity can occur in several different ways.
  • 2.4K
  • 10 Mar 2023
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