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Topic Review
Saline Lakes
Saltwater lakes around the world are drying at a rapid rate. These lakes are present in arid and semi-arid regions where evaporation exceeds precipitation. The Aral Sea and Lake Urmia are examples for such rapidly drying lakes. These two lakes have lost up to 90% of their former area in the past 50 years.  
  • 2.3K
  • 28 Oct 2020
Topic Review
Curcumin: Biochemistry and Antitumoral Action
Curcumin is a pigment with a strong yellow colour found and the main active component of Curcuma longa, a perennial Zingiberaceae plant native to southwest India, but now grown across the South and Southeast Asia, especially in China and India. It is used for centuries as a spice and currently it is viewed as a nutraceutical due to the increasing number of scientific studies demonstrating its anti-oxidant, anti-inflammatory, anti-tumoral and cancer preventive properties. Its chemical structure comprises two aromatic ring systems with o-methoxy phenol groups connected by a seven-carbon linker consisting of an α,β-unsaturated β-diketone with tautomerism when in solution.
  • 2.3K
  • 07 Feb 2021
Topic Review
Acrylamide in Bakery Products
Acrylamide is a contaminant as defined in Council Regulation (EEC) No 315/93 and as such, it is considered a chemical hazard in the food chain. The toxicity of acrylamide has been acknowledged since 2002, among its toxicological effects on humans being neurotoxicity, genotoxicity, carcinogenicity, and reproductive toxicity. Acrylamide has been classified as carcinogenic in the 2A group, with human exposure leading to progressive degeneration of the peripheral and central nervous systems characterized by cognitive and motor abnormalities. Bakery products (bread, crispbread, cakes, batter, breakfast cereals, biscuits, pies, etc.) are some of the major sources of dietary acrylamide.
  • 2.3K
  • 21 May 2021
Topic Review
CO in Fresh Meat Packaging
Modified atmosphere packaging (MAP) of foods has been a promising area of research, but much remains to be known regarding the use of unconventional gases such carbon monoxide (CO). The use of CO for meat and seafood packaging is not allowed in most countries due to the potential toxic effect, and its use is controversial in some countries. The commercial application of CO in food packaging was not then considered feasible because of possible environmental hazards for workers. CO has previously been reported to mask muscle foods’ spoilage, and this was the primary concern raised for the prohibition, as this may mislead consumers. 
  • 2.3K
  • 05 Jul 2021
Topic Review
HS-SPME-GC–MS Volatile Profile Characterization of Peach
The volatile compounds of eight peach varieties (Prunus persica L.)—“Filina”, “Gergana”, “Ufo-4”, “July lady”, “Laskava”, “Flat Queen”, “Evmolpiya”, and “Morsiani 90”—growing in Bulgaria were analyzed for the first time. Gas chromatography–mass spectrometry (GC–MS) analysis and the HS-SPME technique revealed the presence of 65 volatile compounds; the main identified components were aldehydes, esters, and fatty acids. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative quantities of the identified volatile compounds depended on the studied peach variety. The results obtained could be successfully applied for the metabolic chemotaxonomy of peaches.
  • 2.3K
  • 10 Feb 2022
Topic Review
Empirical Theory of Perception
An empirical theory of perception is a type of explanation for how percepts form. These theories hold that sensory systems incorporate information about the statistical properties of the natural world into their design and relate incoming stimuli to this information, rather than analyzing sensory stimulation into its components or features.
  • 2.3K
  • 20 Oct 2022
Topic Review
Damen Stan Patrol Vessel
The Dutch shipbuilding firm The Damen Group, designs and manufactures a wide variety of vessels, including a range of related patrol vessels known generally as the Damen Stan Patrol Vessels. The Damen Stan patrol vessel designs' names include a four digit code, where the first two digits are the vessel's length, in metres, and the second two digits are its width. Over a dozen nations have classes of vessels based on the Damen Stan 4207 patrol vessel design, which are 42 metres (138 ft) long and 7 metres (23 ft) wide. The United States Coast Guard's Sentinel class cutters, based on the Damen Stan 4708 patrol vessel design, are 47 metres (154 ft) long and 8 metres (26 ft) wide. In the late 1990s three 41 patrol vessels were built for service in the Dutch Antilles, and experience with those vessels informed the later designs of the 4207 and 4708. Rather than design vessels that were strictly for naval use, the underlying Damen Stan patrol vessel designs do not include weapons, or a sensor suite. The designs have been adapted for constabulary duties, and for fishery and environmental patrols. According to Sanjay Badri-Maharaj, of the -Institute for Defence Studies and Analyses, described how adding an autocannon and military class sensor suite to the USCG's Sentinel class boosted its cost per vessel from $20 million United States dollar to $65 million. In recent years Damen has developed Damen Stan patrol vessels based on their Sea Axe bow design. The Stan 4207 design are 42.8-metre (140 ft) patrol vessels. They are 7.1 metres (23 ft) wide, and can travel at 22 knots (41 km/h; 25 mph). They are designed to carry a complement of approximately a dozen. The Stan 4708 are 46.8 metres (154 ft) long, 8.11 metres (26.6 ft) wide, have a maximum speed of 23.8 knots (44.1 km/h; 27.4 mph), and carry a complement of 16-24.
  • 2.3K
  • 29 Nov 2022
Topic Review
Origin of Ugrians
Both genetic and archaeological data indicate the admixture of the Mezhovskaya population with northern forest hunters in the late Bronze Age, which gave rise to a “proto-Ugric” community. This finding is consistent with the linguistic reconstruction of the proto-Ugric language. Genetic data indicate an admixture of proto-Hungarians with early Sarmatians and early Huns, and the first admixture can be reconciled with the formation of the Gorokhovo culture and its integration into the early Sarmatian Prokhorovka culture, while the second admixture corresponds to the transformation of the Sargat and Sarmatian cultures due to Xiongnu invasions.
  • 2.3K
  • 08 Aug 2023
Topic Review
Shoebill (Balaeniceps rex)
The Shoebill (Balaeniceps rex), also known as the whalehead or shoe-billed stork, is a large, rare avian species native to the freshwater swamps and wetlands of tropical East Africa. Recognizable by its massive, shoe-shaped bill and prehistoric appearance, the shoebill occupies a unique phylogenetic position within the order Pelecaniformes, with no close living relatives. It is listed as Vulnerable by the International Union for Conservation of Nature (IUCN) due to its small and declining population.
  • 2.3K
  • 19 Jun 2025
Topic Review
Rangelands Livestock Production Systems
Rangelands as referred to herein can be defined as uncultivated lands that provide multiple ecosystem services for society, sustain habitat for grazing and browsing animals, and support the livelihoods of pastoralists and ranchers [1][2]. Under this definition rangelands comprise up to 70% of the world’s land area and include natural grasslands, deserts, temperate forests, and tropical forests [1]. Greenhouse gases (GHGs) released into the lower atmosphere mainly by the burning of fossil fuels and other anthropogenic activities have caused the earth’s temperature to rise by 1 °C since the 1860s [3][4]. If GHG emissions continue to rise, an increase in global temperature up to 3 to 5 °C is projected by the end of this century [4]. Extreme weather events are already increasing in frequency and severity in the US and globally [3][4][5]. Global concern is growing over the possibility that eventual irreversible, catastrophic climate change will result in massive loss of human livelihoods and mortality through adverse impacts on food production systems over both croplands and rangelands [3][4][6][7][8][9][10][11][12].
  • 2.3K
  • 05 Nov 2020
Topic Review
Food Packaging
Demand for food packaging is on the rise as a result of increasing global demand for food due to population growth. Most of the food packaging are used on-the-go and are single-use plastics that are disposed of within a short space of time. The bulk of this plastic waste has found its way into the environment contaminating land, water and the food chain. The food industry is encouraged to reduce, reuse and recycle packaging materials. 
  • 2.3K
  • 09 Apr 2021
Topic Review
Silver Nanoparticles in Plant Disease Management
Exploration of nanoparticles (NPs) for various biological and environmental applications has become one of the most important attributes of nanotechnology. Due to remarkable physicochemical properties, silver nanoparticles (AgNPs) are the most explored and used NPs in wide-ranging applications. Also, they have proven to be of high commercial use since they possess great chemical stability, conductivity, catalytic activity, and antimicrobial potential. Though several methods including chemical and physical methods have been devised, biological approaches using organisms such as bacteria, fungi, and plants have emerged as economical, safe, and effective alternatives for the biosynthesis of AgNPs. Recent studies highlight the potential of AgNPs in modern agricultural practices to control the growth and spread of infectious pathogenic microorganisms since the introduction of AgNPs effectively reduces plant diseases caused by a spectrum of bacteria and fungi.
  • 2.3K
  • 15 Aug 2022
Topic Review
Gâteaux Derivative
In mathematics, the Gâteaux differential or Gâteaux derivative is a generalization of the concept of directional derivative in differential calculus. Named after René Gâteaux, a French mathematician who died young in World War I, it is defined for functions between locally convex topological vector spaces such as Banach spaces. Like the Fréchet derivative on a Banach space, the Gâteaux differential is often used to formalize the functional derivative commonly used in the calculus of variations and physics. Unlike other forms of derivatives, the Gâteaux differential of a function may be nonlinear. However, often the definition of the Gâteaux differential also requires that it be a continuous linear transformation. Some authors, such as (Tikhomirov 2001), draw a further distinction between the Gâteaux differential (which may be nonlinear) and the Gâteaux derivative (which they take to be linear). In most applications, continuous linearity follows from some more primitive condition which is natural to the particular setting, such as imposing complex differentiability in the context of infinite dimensional holomorphy or continuous differentiability in nonlinear analysis.
  • 2.3K
  • 25 Oct 2022
Topic Review
Heavy Metals Removal from Contaminated Soil by Phytoremediation
Pollution from heavy metals is one of the significant environmental concerns facing the world today. Human activities, such as mining, farming, and manufacturing plant operations, can allow them access to the environment. Heavy metals polluting soil can harm crops, change the food chain, and endanger human health. Thus, the overarching goal for humans and the environment should be the avoidance of soil contamination by heavy metals. Heavy metals persistently present in the soil can be absorbed by plant tissues, enter the biosphere, and accumulate in the trophic levels of the food chain. The removal of heavy metals from contaminated soil can be accomplished using various physical, synthetic, and natural remediation techniques (both in situ and ex situ). The most controllable (affordable and eco-friendly) method among these is phytoremediation. The removal of heavy metal defilements can be accomplished using phytoremediation techniques, including phytoextraction, phytovolatilization, phytostabilization, and phytofiltration.
  • 2.3K
  • 21 Jul 2023
Topic Review
Algal Synthesis of Metallic Nanoparticles
Metal nanoparticles (NPs) have received much attention for potential applications in medicine (mainly in oncology, radiology and infectiology), due to their intriguing chemical, electronical, catalytical, and optical properties such as surface plasmon resonance (SPR) effect. They also offer ease in controlled synthesis and surface modification (e.g., tailored properties conferred by capping/protecting agents including N-, P-, COOH-, SH-containing molecules and polymers such as thiol, disulfide, ammonium, amine, and multidentate carboxylate), which allows (i) tuning their size and shape (e.g., star-shaped and/or branched) (ii) improving their stability, monodispersity, chemical miscibility, and activity, (iii) avoiding their aggregation and oxidation over time, (iv) increasing their yield and purity. The bottom-up approach, where the metal ions are reduced in the NPs grown in the presence of capping ligands, has been widely used compared to the top-down approach. Besides the physical and chemical synthesis methods, the biological method is gaining much consideration. Indeed, several drawbacks have been reported for the synthesis of NPs via physical (e.g., irradiation, ultrasonication) and chemical (e.g., electrochemisty, reduction by chemicals such as trisodium citrate or ascorbic acid) methods (e.g., cost, and/ortoxicity due to use of hazardous solvents, low production rate, use of huge amount of energy). However, (organic or inorganic) eco-friendly NPs synthesis exhibits a sustainable, safe, and economical solution. Thereby, a relatively new trend for fast and valuable NPs synthesis from (live or dead) algae (i.e., microalgae, macroalgae and cyanobacteria) has been observed, especially because of its massive presence on the Earth's crust and their unique properties (e.g., capacity to accumulate and reduce metallic ions, fast propagation).  This work highlights affordable, fast, eco-friendly, efficient and safe strategies to produce nanoparticles for theranostic purposes. 
  • 2.3K
  • 27 Oct 2020
Topic Review
Chinese Herbal Medicines for Sepsis Treatment
Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection; the pathophysiology of sepsis is complex. The incidence of sepsis is steadily increasing, with worldwide mortality ranging between 30% and 50%. Current treatment approaches mainly rely on the timely and appropriate administration of antimicrobials and supportive therapies, but the search for pharmacotherapies modulating the host response has been unsuccessful. Chinese herbal medicines, i.e., Chinese patent medicines, Chinese herbal prescriptions, and single Chinese herbs, play an important role in the treatment of sepsis through multicomponent, multipathway, and multitargeting abilities and have been officially recommended for the management of COVID-19.
  • 2.3K
  • 01 Nov 2021
Topic Review
Fish Exposed to Ammonia Nitrogen
Ammonia nitrogen is the major oxygen-consuming pollutant in aquatic environments. Exposure to ammonia nitrogen in the aquatic environment can lead to bioaccumulation in fish, and the ammonia nitrogen concentration is the main determinant of accumulation. In most aquatic environments, fish are at the top of the food chain and are most vulnerable to the toxic effects of high levels of ammonia nitrogen exposure. In fish exposed to toxicants, ammonia-induced toxicity is mainly caused by bioaccumulation in certain tissues. Ammonia nitrogen absorbed in the fish enters the circulatory system and affects hematological properties. Ammonia nitrogen also breaks balance in antioxidant capacity and causes oxidative damage. In addition, ammonia nitrogen affects the immune response and causes neurotoxicity because of the physical and chemical toxicity. 
  • 2.3K
  • 23 Nov 2021
Topic Review
Hydrogel Adsorbents
The performance of hydrogel adsorbents depends on the constituents of the gels and the functions produced by the polymer networks of the gels. Research on hydrogels utilizing the characteristic functions of polymer networks has increased over the last decade. The functions of polymer networks are key to the development of advanced adsorbents for the removal of various pollutants.
  • 2.3K
  • 15 Jun 2022
Topic Review
Macchi C.200
The Macchi C.200 Saetta (Italian: Lightning), or MC.200, was a fighter aircraft developed and manufactured by Aeronautica Macchi in Italy. It was operated in various forms by the Regia Aeronautica (Italian Air Force) who used the type throughout the Second World War. The C.200 was designed by Mario Castoldi, Macchi's lead designer, to serve as a modern monoplane fighter aircraft, furnished with retractable landing gear and powered by a radial engine. It possessed excellent maneuverability and the C.200's general flying characteristics left little to be desired. Stability in a high-speed dive was exceptional, but it was underpowered and underarmed in comparison to its contemporaries. Early on, there were a number of crashes caused by stability problems, nearly resulting in the grounding of the type, which was ultimately addressed via aerodynamic modifications to the wing. From the time Italy entered the Second World War on 10 June 1940, until the signing of the armistice of 8 September 1943, the C. 200 flew more operational sorties than any other Italian aircraft. The Saetta saw operational service in Greece, North Africa, Yugoslavia, across the Mediterranean and the Soviet Union (where it obtained an excellent kill to loss ratio of 88 to 15). Its very strong all-metal construction and air-cooled engine made the aircraft ideal for conducting ground attack missions; several units flew it as a fighter-bomber. Over 1,000 aircraft had been constructed by the end of the war.
  • 2.3K
  • 31 Oct 2022
Topic Review
Reduce (Parallel Pattern)
Reduce is a collective communication primitive used in the context of a parallel programming model to combine multiple vectors into one, using an associative binary operator [math]\displaystyle{ \oplus }[/math]. Every vector is present at a distinct processor in the beginning. The goal of the primitive is to apply the operator in the order given by the processor-indices to the vectors until only one is left. The reduction of sets of elements is an integral part of programming models such as Map Reduce, where a function is applied (mapped) to all elements before they are reduced. Other parallel algorithms use reduce as a primary operation to solve more complex problems. The Message Passing Interface implements it in the operations MPI_Reduce and MPI_Allreduce, with the difference that the result is available at one (root) processing unit or all of them. Closely related to reduce is the broadcast operation, which distributes data to all processors. Many reduce algorithms can be used for broadcasting by reverting them and omitting the operator.
  • 2.3K
  • 05 Dec 2022
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