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Topic Review
Magic Number
In nuclear physics, a magic number is a number of nucleons (either protons or neutrons, separately) such that they are arranged into complete shells within the atomic nucleus. As a result, atomic nuclei with a 'magic' number of protons or neutrons are much more stable than other nuclei. The seven most widely recognized magic numbers as of 2019 are 2, 8, 20, 28, 50, 82, and 126 (sequence A018226 in the OEIS). For protons, this corresponds to the elements helium, oxygen, calcium, nickel, tin, lead and the hypothetical unbihexium, although 126 is so far only known to be a magic number for neutrons. Atomic nuclei consisting of such a magic number of nucleons have a higher average binding energy per nucleon than one would expect based upon predictions such as the semi-empirical mass formula and are hence more stable against nuclear decay. The unusual stability of isotopes having magic numbers means that transuranium elements could theoretically be created with extremely large nuclei and yet not be subject to the extremely rapid radioactive decay normally associated with high atomic numbers. Large isotopes with magic numbers of nucleons are said to exist in an island of stability. Unlike the magic numbers 2–126, which are realized in spherical nuclei, theoretical calculations predict that nuclei in the island of stability are deformed. Before this was realized, higher magic numbers, such as 184, 258, 350, and 462 (sequence A033547 in the OEIS), were predicted based on simple calculations that assumed spherical shapes: these are generated by the formula [math]\displaystyle{ 2(\tbinom n1+ \tbinom n2+\tbinom n3) }[/math] (see Binomial coefficient). It is now believed that the sequence of spherical magic numbers cannot be extended in this way. Further predicted magic numbers are 114, 122, 124, and 164 for protons as well as 184, 196, 236, and 318 for neutrons. However, more modern calculations predict 228 and 308 for neutrons, along with 184 and 196.
  • 2.0K
  • 03 Nov 2022
Topic Review
Flavanols and Methylxanthines in Cocoa
Despite the health benefits associated with the ingestion of the bioactive compounds in cocoa, the high concentrations of polyphenols and methylxanthines in the raw cocoa beans negatively influence the taste, confer the astringency and bitterness, and affect the stability and digestibility of the cocoa products. It is, therefore, necessary to process cocoa beans to develop the characteristic color, taste, and flavor, and reduce the astringency and bitterness, which are desirable in cocoa products. 
  • 2.0K
  • 08 Feb 2023
Topic Review
Development of Rudimentary Structure of Mammary Gland
The mammary gland is a compound, branched tubuloalveolar structure and a major characteristic of mammals. The mammary gland has evolved from epidermal apocrine glands, the skin glands as an accessory reproductive organ to support postnatal survival of offspring by producing milk as a source of nutrition. The mammary gland development begins during embryogenesis as a rudimentary structure that grows into an elementary branched ductal tree and is embedded in one end of a larger mammary fat pad at birth. At the onset of ovarian function at puberty, the rudimentary ductal system undergoes dramatic morphogenetic change with ductal elongation and branching. During pregnancy, the alveolar differentiation and tertiary branching are completed, and during lactation, the mature milk-producing glands eventually develop. The early stages of mammary development are hormonal independent, whereas during puberty and pregnancy, mammary gland development is hormonal dependent. The mammary gland develops as a rudimentary structure from a thickening under the ventral skin during embryogenesis. This rudimentary structure grows into a rudimentary branched ductal tree embedded in one end of a larger mammary fat pad at birth. The embryonic development of the mammary gland is a series of several hormone-independent specialized events.
  • 2.0K
  • 18 Apr 2022
Topic Review
Cyanobacteria and Microalgae Antibacterial Peptides
Cyanobacteria and microalgae are oxygen-producing photosynthetic unicellular organisms encompassing a great diversity of species, which are able to grow under all types of extreme environments and exposed to a wide variety of predators and microbial pathogens. The antibacterial compounds described for these organisms include organic compounds such as  alkaloids, fatty acids, indoles, macrolides, phenols, pigments and terpenes, among others, but the peptides have an special pharmacological appeal, due to their broad chemical space, achieved by their dual biosynthetic alternatives in cyanobacteria, the ribosomal synthesis, or a polypeptide assembly through the non-ribosomal peptide synthases. This diversity ensures a broad range of biological properties with a large pharmacological potential.   
  • 2.0K
  • 14 Jan 2021
Topic Review
Rumen
The rumen is the first digester in the digestive system of ruminants, which is located on the left side of the abdominal cavity. Rumen occupying almost the entire left abdominal cavity. In its front part is the rumen vestibule, which connects with the esophagus through the cardia. Rumen microbes anaerobically ferment complex lignocellulose plant materials which cannot be directly utilized by a host, into monomers which are further degraded into different microbial end-products, including volatile fatty acids, hydrogen, carbon dioxide, methane, and other fermentation products necessary for essential metabolic pathways. The complex rumen microbiome network is dominated by bacteria, archaea, protozoa, and anaerobic fungi.
  • 2.0K
  • 23 Feb 2021
Topic Review
Magnetic Holography
The principle of magnetic holograms and its application to holographic memory are reviewed. A magnetic hologram was recorded through a thermomagnetic recording as a difference in magnetization direction and reconstructed with the magneto-optical effect. To achieve a bright reconstruction image, it is important to record deep magnetic fringes on the materials with large Faraday rotation coefficients. This technique was applied to the holographic memory using transparent magnetic garnets as a recording material. The first reconstruction image was dark and noisy, but improvements in the recording conditions resulted in error-free recording and reconstruction of the magnetic hologram. To form deep magnetic fringes, insertion of heat dissipation (HD) layers into recording layer was proposed. It was found that this HD multilayer medium showed diffraction efficiency higher than that of a single layer medium, and error-free recording and reconstruction were also achieved, using magnetic assisted recording. These results suggest that HD multilayer media have potential applications in recording media of magnetic holographic data storage. In future, a high recording density technique, such as multiple recording, should be developed.
  • 2.0K
  • 24 Jun 2021
Topic Review
Marginal Oil Resources
The term “marginal oil resource” refers to an oil reservoir that has hydrocarbon resource preservation but cannot meet the criteria of resources under the U.S Securities and Exchange Commission (SEC) standards. When oilfields step into their late life, most of their economic petroleum reserves have been well developed, and their focuses need to be switched to their intact marginal resources.
  • 2.0K
  • 14 Mar 2022
Topic Review
New Human Resource Management Practices on Innovation Performance
The conventional set of human resource management practices as an important source should create a flexible and innovative view to maintain the significant effects in unique organizational strategies that distinguish committed employees, wherever continuous innovation is essential for gaining organizational sustainability. The competitive and unpredictable situation requires new human resource practices (NHRM) to deal with problems in the organizations to enhance their climate, contribute and heighten innovation performance. This shifts the entire scenario to technological processes such as E-recruitment selection, training, reward systems, employee involvement in decision-making, and teamwork linked strongly with organizational performance and HR outcomes. Evolutionary research is required on HRM practices because different researchers have indicated that the studies are scarce, as such research examines the relationship between NHRM and innovation performance. 
  • 2.0K
  • 24 Mar 2022
Biography
George Albert Smith
George Albert Smith (Film pioneer, 4 January 1864 – 17 May 1959) was an English stage hypnotist, psychic, magic lantern lecturer, Fellow of the Royal Astronomical Society, inventor and a key member of the loose association of early film pioneers dubbed the Brighton School by French film historian Georges Sadoul. He is best known for his controversial work with Edmund Gurney at the Society for
  • 2.0K
  • 15 Nov 2022
Topic Review
Complementarity
In physics, complementarity is a conceptual aspect of quantum mechanics that Niels Bohr regarded as an essential feature of the theory. The complementarity principle holds that objects have certain pairs of complementary properties which cannot all be observed or measured simultaneously. An example of such a pair is position and momentum. Bohr considered one of the foundational truths of quantum mechanics to be the fact that setting up an experiment to measure one quantity of a pair, for instance the position of an electron, excludes the possibility of measuring the other, yet understanding both experiments is necessary to characterize the object under study. In Bohr's view, the behavior of atomic and subatomic objects cannot be separated from the measuring instruments that create the context in which the measured objects behave. Consequently, there is no "single picture" that unifies the results obtained in these different experimental contexts, and only the "totality of the phenomena" together can provide a completely informative description.
  • 2.0K
  • 14 Nov 2022
Topic Review
Structure and Genome Organization of SARS-CoV-2
Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) belongs to the realm Riboviria, order Nidovirales, suborder Cornidovirineae, family Coronaviridae, subfamily Orthocoronavirinae, genus Betacoronavirus (lineage B), subgenus Sarbecovirus, and the species severe acute respiratory syndrome-related coronavirus. SARS-CoV-2 is a positive-sense, single stranded RNA virus whose genome size is ~29,903 bp.
  • 2.0K
  • 17 Nov 2022
Topic Review Video
3D Visualisation in Railway Tunnel SubSurface Inspection
Railway Tunnel SubSurface Inspection (RTSSI) is essential for targeted structural maintenance. ‘Effective’ detection, localisation and characterisation of fully concealed features (i.e., assets, defects) is the primary challenge faced by RTSSI engineers, particularly in historic masonry tunnels. Clear conveyance and communication of gathered information to end-users poses the less frequently considered secondary challenge.
  • 2.0K
  • 22 Nov 2022
Topic Review
Unmanned Aerial Vehicle Routing Problems
Unmanned aerial vehicle (UAV) routing is transitioning from an emerging topic to a growing research area as the 3D flexible utilization of airspace, promogulated by UAVs, is a potential game-changer in solving the urban air mobility challenge by allowing to reshape transportation and logistics in the future. This has revealed a need to classify different types of research and examine the general characteristics of the research area. This research aims to assist in identifying the main topics and emerging research streams and provides a published overview of the current state and contributions to the area of the UAV routing problem (UAVRP) and a general categorization of the vehicle routing problem (VRP) followed by a UAVRP classification with a graphical taxonomy based on the analysis of UAVRP current status. To achieve this, an analysis of the existing research contributions promulgated in this domain is conducted. This analysis is used to identify the current state of UAVRP and the gaps related to the UAVs’ flight dynamics and weather conditions, which significantly influence the fuel consumption of the UAV when modeling the UAVRP.
  • 2.0K
  • 14 Jul 2020
Topic Review
Management of Herbaceous/Horticultural Crops
Preserving soil quality and increasing soil water availability is an important challenge to ensure food production for a growing global population. As demonstrated by several studies, conservative crop management, combined with soil cover and crop diversification, can significantly reduce soil and water losses. 
  • 2.0K
  • 07 May 2021
Topic Review
Agricultural Fertilization in Europe
Fertilizers stand at the base of current agricultural practices, providing the nutrient sustainment required for growing plants.
  • 2.0K
  • 30 Jul 2021
Topic Review
Molecular Inversion Probe
Molecular Inversion Probe (MIP) belongs to the class of Capture by Circularization molecular techniques for performing genomic partitioning, a process through which one captures and enriches specific regions of the genome. Probes used in this technique are single stranded DNA molecules and, similar to other genomic partitioning techniques, contain sequences that are complementary to the target in the genome; these probes hybridize to and capture the genomic target. MIP stands unique from other genomic partitioning strategies in that MIP probes share the common design of two genomic target complementary segments separated by a linker region. With this design, when the probe hybridizes to the target, it undergoes an inversion in configuration (as suggested by the name of the technique) and circularizes. Specifically, the two target complementary regions at the 5’ and 3’ ends of the probe become adjacent to one another while the internal linker region forms a free hanging loop. The technology has been used extensively in the HapMap project for large-scale SNP genotyping as well as for studying gene copy alterations and characteristics of specific genomic loci to identify biomarkers for different diseases such as cancer. Key strengths of the MIP technology include its high specificity to the target and its scalability for high-throughput, multiplexed analyses where tens of thousands of genomic loci are assayed simultaneously.
  • 2.0K
  • 02 Nov 2022
Topic Review
Milk Exosomes
Milk contains various extracellular vesicles and non-vesicular structures: exosomes (with diameter 40-100 nm), vesicles of other size, fat globules (with diameter 4-6 mkm, containing milk fat globule membranes), and their aggregates. Due to the biocompatibility of milk exosomes, these vesicles have a wide potential as vehicles for oral delivery of therapeutically relevant molecules (drugs and therapeutic nucleic acids).
  • 2.0K
  • 21 Sep 2020
Topic Review
Benefits of Mass Vaccination Programs
Since the late 1940s, mass vaccination programs in the USA have contributed to the significantly reduced morbidity and mortality of infectious diseases. To assist the evaluation of the benefits of mass vaccination programs, the number of individuals who would have suffered death or permanent disability in the USA in 2014, had mass vaccination never been implemented, was estimated for measles, mumps, rubella, tetanus, diphtheria, pertussis, polio, Haemophilus influenzae type b (Hib), hepatitis B, varicella, and human papillomavirus (HPV). The estimates accounted for mortality and morbidity trends observed for these infections prior to mass vaccination and the impact of advances in standard of living and health care. The estimates also considered populations with and without known factors leading to an elevated risk of permanent injury from infection. Mass vaccination prevented an estimated 20 million infections and 12,000 deaths and permanent disabilities in 2014, including 10,800 deaths and permanent disabilities in persons at elevated risk. Though 9000 of the estimated prevented deaths were from liver cirrhosis and cancer, mass vaccination programs have not, at this point, shown empirical impacts on the prevalence of those conditions. Future studies can refine these estimates, assess the impact of adjusting estimation assumptions, and consider additional risk factors that lead to heightened risk of permanent harm from infection.
  • 2.0K
  • 16 Oct 2020
Topic Review
Nanocellulose-Reinforced Rubber Matrix Composites
Research and development of nanocellulose (NC) and nanocellulose-reinforced composite materials have garnered substantial interest in recent years. Rubber is a common material with a large array of applications, greatly attributed to its mechanical strength and versatility. When rubber is extracted from its natural source, it needs to undergo a compounding stage where fillers are added to reinforce the material prior to further processing. The application of nanocellulose and its variants as a substitute of conventional fillers like carbon black (CB) and silica could further reduce environmental impacts and cost as it is derived from organic biomass. Incorporation of nanocellulose as a reinforcing material could also be extended to synthetic rubber composites to carry out a similar function of improving mechanical integrity.
  • 2.0K
  • 04 Mar 2021
Topic Review
Irisin and Incretin Hormones
Incretins are gut hormones that potentiate glucose-stimulated insulin secretion (GSIS) after meals. Glucagon-like peptide-1 (GLP-1) is the most investigated incretin hormone, synthesized mainly by L cells in the lower gut tract. GLP-1 promotes β-cell function and survival and exerts beneficial effects in different organs and tissues. Irisin, a myokine released in response to a high-fat diet and exercise, enhances GSIS. Similar to GLP-1, irisin augments insulin biosynthesis and promotes accrual of β-cell functional mass. In addition, irisin and GLP-1 share comparable pleiotropic effects and activate similar intracellular pathways. The insulinotropic and extra-pancreatic effects of GLP-1 are reduced in type 2 diabetes (T2D) patients but preserved at pharmacological doses. GLP-1 receptor agonists (GLP-1RAs) are therefore among the most widely used antidiabetes drugs, also considered for their cardiovascular benefits and ability to promote weight loss. Irisin levels are lower in T2D patients, and in diabetic and/or obese animal models irisin administration improves glycemic control and promotes weight loss. This review aims to describe the similarities between GLP-1 and irisin and to propose a new potential axis involving the gut, muscle, and endocrine pancreas that controls energy homeostasis.
  • 2.0K
  • 10 Mar 2021
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