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Topic Review
Organic Residues and Soils
The management of large volumes of organic residues generated in different livestock, urban, agricultural and industrial activities is a topic of environmental and social interest. The high organic matter content of these residues means that their application as soil organic amendments in agriculture is considered one of the more sustainable options, as it could solve the problem of the accumulation of uncontrolled wastes while improving soil quality and avoiding its irreversible degradation. However, the behavior of pesticides applied to increase crop yields could be modified in the presence of these amendments in the soil.
  • 1.4K
  • 29 Apr 2021
Topic Review
Operation Bertram
Operation Bertram was a Second World War deception operation practised by the Allied forces in Egypt led by Bernard Montgomery, in the months before the Second Battle of El Alamein in 1942. Bertram was devised by Dudley Clarke to deceive Erwin Rommel about the timing and location of the Allied attack. The operation consisted of physical deceptions using dummies and camouflage, designed and made by the British Middle East Command Camouflage Directorate led by Geoffrey Barkas. These were accompanied by electromagnetic deceptions codenamed Operation Canwell, using false radio traffic. All of these were planned to make the Axis believe that the attack would take place to the south, far from the coast road and railway, about two days later than the real attack. Bertram consisted of the creation of the appearance of army units where none existed and in concealing armour, artillery and matériel. Dummy tanks and guns were made mainly of local materials including calico and palm-frond hurdles. Real tanks were disguised as trucks, using light "Sunshield" canopies. Field guns and their limbers were also disguised as trucks, their real wheels visible, under a simple box-shaped "Cannibal" canopy to give the shape of a truck. Petrol cans were stacked along the sides of existing revetted trenches, hidden in the shadows. Food was stacked in piles of boxes and draped with camouflage nets to resemble trucks. Trucks were parked openly in the tank assembly area for some weeks. Real tanks were similarly parked openly, far behind the front. Two nights before the attack, the tanks replaced the trucks, being covered with "Sunshields" before dawn. The tanks were replaced that same night with dummies in their original positions, so the armour remained seemingly two or more days' journey behind the front line. To reinforce the impression that the attack was not ready, a dummy water pipeline was constructed, at an apparent rate of 5 mi (8.0 km) per day. Some days' worth remained to be built at the time of the attack; dummy tanks, guns and supplies were constructed to the south. After the battle, the captured German panzerarmee general Wilhelm Ritter von Thoma told Montgomery that he had believed the Allies had at least one more armoured division than they did and that the attack would be in the south. Rommel's stand-in, general Georg Stumme, thought the attack would not begin for several weeks. Bertram had succeeded; when announcing the victory at El Alamein in the House of Commons, Winston Churchill praised the camouflage operation.
  • 1.4K
  • 02 Nov 2022
Topic Review
Echoic Memory
Echoic memory is the sensory memory that registers specific to auditory information (sounds). Once an auditory stimulus is heard, it is stored in memory so that it can be processed and understood. Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Since echoic memories are heard once, they are stored for slightly longer periods of time than iconic memories (visual memories). Auditory stimuli are received by the ear one at a time before they can be processed and understood. For instance, hearing the radio is very different from reading a magazine. A person can only hear the radio once at a given time, while the magazine can be read over and over again. It can be said that the echoic memory is like a "holding tank" concept, because a sound is unprocessed (or held back) until the following sound is heard, and only then can it be made meaningful. This particular sensory store is capable of storing large amounts of auditory information that is only retained for a short period of time (3–4 seconds). This echoic sound resonates in the mind and is replayed for this brief amount of time shortly after being heard. Echoic memory encodes only moderately primitive aspects of the stimuli, for example pitch, which specifies localization to the non-association brain regions.
  • 1.4K
  • 21 Oct 2022
Topic Review
Microbial Biofertilizers in Rhizosphere Management
The world’s human population continues to increase, posing a significant challenge in ensuring food security as soil nutrients and fertility decrease with time. Thus, there is a need to increase agricultural productivity to meet the growing population's food demands. A high level of chemical fertilizers to increase food production is damaging ecological balance and human health. It is becoming too expensive for many farmers to afford. The exploitation of beneficial soil microorganisms as a substitute for chemical fertilizers in food production is one potential solution to this conundrum. Microorganisms, such as plant growth-promoting rhizobacteria and mycorrhizal fungi, have demonstrated their ability to formulate biofertilizers in the agricultural sector, providing plants with nutrients required to enhance their growth, increase yield, manage abiotic and biotic stress, and prevent phytopathogens attack. Beneficial soil microbes have been reported to produce some volatile organic compounds beneficial to plants. The amendment of these microbes with locally available organic materials and nanoparticles is currently used to formulate biofertilizers to increase plant productivity.
  • 1.4K
  • 22 Mar 2021
Topic Review
Cellulose Derivatives-Based Dressings for Wound-Healing Management
Notwithstanding the progress regarding wound-healing management, the treatment of the majority of skin lesions still represents a serious challenge for biomedical and pharmaceutical industries. Thus, the attention of the researchers has turned to the development of novel materials based on cellulose derivatives. Cellulose derivatives are semi-synthetic biopolymers, which exhibit high solubility in water and represent an advantageous alternative to water-insoluble cellulose. These biopolymers possess excellent properties, such as biocompatibility, biodegradability, sustainability, non-toxicity, non-immunogenicity, thermo-gelling behavior, mechanical strength, abundance, low costs, antibacterial effect, and high hydrophilicity. They have an efficient ability to absorb and retain a large quantity of wound exudates in the interstitial sites of their networks and can maintain optimal local moisture. Cellulose derivatives also represent a proper scaffold to incorporate various bioactive agents with beneficial therapeutic effects on skin tissue restoration. Due to these suitable and versatile characteristics, cellulose derivatives are attractive and captivating materials for the development of multiple biomedical and pharmaceutical applications, such as wound dressings, drug delivery devices, and tissue engineering.
  • 1.4K
  • 29 Mar 2022
Topic Review
Prion
Prions are misfolded proteins that have the ability to transmit their misfolded shape onto normal variants of the same protein. They characterize several fatal and transmissible neurodegenerative diseases in humans and many other animals. It is not known what causes a normal protein to misfold, but the resulting abnormal three-dimensional structure confers infectious properties by collapsing nearby protein molecules into the same shape. The word prion is derived from the term, "proteinaceous infectious particle". In comparison to all other known infectious agents such as viroids, viruses, bacteria, fungi, and parasites, all of which contain nucleic acids (DNA, RNA, or both), the hypothesized role of a protein as an infectious agent stands in contrast. Prion isoforms of the prion protein (PrP), whose specific function is uncertain, are hypothesized as the cause of transmissible spongiform encephalopathies (TSEs), including scrapie in sheep, chronic wasting disease (CWD) in deer, bovine spongiform encephalopathy (BSE) in cattle (commonly known as "mad cow disease") and Creutzfeldt–Jakob disease (CJD) in humans. All known prion diseases in mammals affect the structure of the brain or other neural tissue; all are progressive, have no known effective treatment, and are always fatal. Until 2015, all known mammalian prion diseases were caused by the prion protein (PrP); however, in 2015 it was hypothesized that multiple system atrophy (MSA) was caused by a prion form of alpha-synuclein. Prions are a type of intrinsically disordered protein, which change their conformation unless they are bound to a specific partner such as another protein. With a prion, two protein chains are stabilized if one binds to another in the same conformation. The probability of this happening is low, but once it does the combination of the two is very stable. Then more units can get added, making a sort of "fibril". Prions form abnormal aggregates of proteins called amyloids, which accumulate in infected tissue and are associated with tissue damage and cell death. Amyloids are also responsible for several other neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. A prion disease is a type of proteopathy, or disease of structurally abnormal proteins. In humans, prions are believed to be the cause of Creutzfeldt–Jakob disease (CJD), its variant (vCJD), Gerstmann–Sträussler–Scheinker syndrome (GSS), fatal familial insomnia (FFI), and kuru. There is also evidence suggesting prions may play a part in the process of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS); these have been termed prion-like diseases. Several yeast proteins have also been identified as having prionogenic properties, as well as a protein involved in modification of synapses during the formation of memories (see Eric Kandel § Molecular changes during learning). Prion replication is subject to epimutation and natural selection just as for other forms of replication, and their structure varies slightly between species. Prion aggregates are stable, and this structural stability means that prions are resistant to denaturation by chemical and physical agents: they cannot be destroyed by ordinary disinfection or cooking. This makes disposal and containment of these particles difficult.
  • 1.4K
  • 14 Nov 2022
Topic Review
Colorectal Cancer Cells
The majority of deaths related to colorectal cancer (CRC) are associated with the metastatic process. Alternative therapeutic strategies, such as traditional folk remedies, deserve attention for their potential ability to attenuate the invasiveness of CRC cells. The aim of this study is to investigate the biological activity of brown Cuban propolis (CP) and its main component nemorosone (NEM) and to describe the molecular mechanism(s) by which they inhibit proliferation and metastatic potential of 2 CRC cell lines. CP and NEM significantly decreased cell viability and inhibited clonogenic capacity of CRC cells in a dose and time-dependent manner, by arresting the cell cycle in the G0/G1 phase and inducing apoptosis. Furthermore, CP and NEM downregulated BCL2 gene expression and upregulated the expression of the proapoptotic genes TP53 and BAX, with a consequent activation of caspase 3/7. They also attenuated cell migration and invasion by inhibiting MMP9 activity, increasing E-cadherin and decreasing β-catenin and vimentin expression, proteins involved in the epithelial–mesenchymal transition (EMT). NEM, besides displaying antiproliferative activity on CRC cells, is able to decrease their metastatic potential by modulating EMT-related molecules. These findings provide new insights about the antitumoral properties of CP, due to NEM content.  
  • 1.4K
  • 01 Nov 2020
Topic Review
Bisphenols
Bisphenols (BPs), and especially bisphenol A (BPA), are known endocrine disruptors (EDCs), capable of interfering with estrogen and androgen activities, as well as being suspected of other health outcomes.
  • 1.4K
  • 28 Oct 2020
Topic Review
Callose
Callose is a β-(1,3)-D-glucan polysaccharide with some β-1,6-branches that exists in all multicellular green algae and higher plants.
  • 1.4K
  • 27 Apr 2021
Topic Review
Taekwondo Training and Obesity
Taekwondo training is an effective exercise that can prevent or positively improve obesity. In addition, Taekwondo has value as a lifestyle sport that can contribute to the promotion of human health, not just bounded in the field of martial arts and sports.
  • 1.4K
  • 24 Nov 2021
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