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Bergamot Oil: Botany, Production, Pharmacology
Bergamot essential oil (BEO) is the result of the mechanical manipulation (cold pressing) of the exocarp (flavedo) of the hesperidium of Citruslimon (L.) Osbeck Bergamot Group (synonym Citrus × bergamia Risso & Poit.), resulting in the bursting of the oil cavities embedded in the flavedo and the release of their contents. It is chemically dominated by monoterpene hydrocarbons (i.e., limonene), but with significant percentages of oxygenated monoterpenes (i.e., linalyl acetate) and of non-volatile oxygen heterocyclic compounds (i.e., bergapten). 
  • 2.7K
  • 13 Apr 2022
Topic Review
Synthetic Applications of Lawesson’s Reagent in Organic Synthesis
Lawesson’s reagent (LR) is a well-known classic example of a compound with unique construction and unusual chemical behavior, with a wide range of applications in synthetic organic chemistry. Its main functions were rounded for the thionation of various carbonyl groups in the early days. Now its use can help the chemistry community to understand innovative ideas. These include constructing biologically valuable heterocycles, coupling reactions, and the thionation of natural compounds.
  • 2.7K
  • 27 Nov 2021
Topic Review
Amino Acid Catabolism
Amino acids have been extensively studied in nutrition, mainly as key elements for maintaining optimal protein synthesis in the body as well as precursors of various nitrogen-containing compounds. However, it is now known that amino acid catabolism is an important element for the metabolic control of different biological processes, although it is still a developing field to have a deeper understanding of its biological implications. The mechanisms involved in the regulation of amino acid catabolism now include the contribution of the gut microbiota to amino acid oxidation and metabolite generation in the intestine, the molecular mechanisms of transcriptional control, and the participation of specific miRNAs involved in the regulation of amino acid degrading enzymes. In addition, molecules derived from amino acid catabolism play a role in metabolism as they are used in the epigenetic regulation of many genes.
  • 2.7K
  • 02 Aug 2023
Topic Review
Applications of Photosynthetic Systems
       In biological and life science applications photosynthesis is an important process that involves the absorption and transformation of sunlight into chemical energy. During the photosynthesis process, the light photons are captured by the green chlorophyll pigments in their photosynthetic antennae and further funneled to the reaction center. One of the mostimportant light harvesting complexes that are highly important in the study of photosynthesis is the membrane-attached Fenna-Matthews-Olson (FMO) complex found in the green sulfur bacteria. In this review, we discuss the mathematical formulations and computational modeling of some of the light harvesting complexes including FMO. The most recent research developments in the photosynthetic light harvesting complexes are thoroughly discussed. The theoretical background related to the spectral density, quantum coherence and density functional theory (DFT) has been elaborated.Further, details about the transfer and excitation of energy in different sites of the FMO complex along with other vital photosynthetic light harvesting complexes have also been provided. In particular, we will review recent results on spectral density, quantum coherence, quantum entanglement and excitonic energies of different pigments in the light harvesting complexes. We will also discuss the issues pertinent to the highest occupied orbital (HOMO) and lowest unoccupiedorbital (LUMO) energies for all the bacteriochlorophyll utilizing the time-dependent DFT. These results would be helpful in studying the excitonic dynamics of the light harvesting complexes among different applications. Finally, we conclude this review by providing the current and potential applications in environmental science, energy, health and medicine, where such mathematical and computational studies of the photosynthesis and the light harvesting complexes can be readily integrated.
  • 2.7K
  • 26 Oct 2020
Topic Review
Dagor Dagorath
The Dagor Dagorath (Sindarin for Battle of Battles) is a fictional battle described in the legendarium of J. R. R. Tolkien. As Tolkien's works were conceived as a fictional "forgotten history" of the world, the Dagor Dagorath represents the coming End of the World, and is often referred to as simply "The End". As Tolkien originally wrote it, The Silmarillion ends with a prophecy by Mandos about the end of the world. The published Silmarillion ends instead with the last paragraph of Valaquenta. This was because Tolkien had abandoned the idea of the "second prophecy of Mandos", and the Valaquenta text, much later, contradicted it openly. However, references to the final battle remain in the published Silmarillion, such as a statement at the end of the Akallabêth that Ar-Pharazôn and his mortal warriors who had set foot on Aman were buried by falling hills, imprisoned in the Caves of the Forgotten until the "Last Battle and Day of Doom". Christopher Tolkien sees the account as similar to the Nordic legend of Ragnarök and J. R. R. Tolkien also made this connection in some of his letters.
  • 2.7K
  • 14 Oct 2022
Topic Review
Memory Span
In psychology and neuroscience, memory span is the longest list of items that a person can repeat back in correct order immediately after presentation on 50% of all trials. Items may include words, numbers, or letters. The task is known as digit span when numbers are used. Memory span is a common measure of working memory and short-term memory. It is also a component of cognitive ability tests such as the WAIS. Backward memory span is a more challenging variation which involves recalling items in reverse order.
  • 2.7K
  • 20 Oct 2022
Topic Review
Acer Aspire Laptops
Acer Aspire (stylized as Λspire or ΛSPIRE) is a series of personal computers by Acer Inc. aimed at the casual household user or for small business use. The Aspire series covers both desktop computers and laptops. Acer developed the series in order to cover from essentials to high performances. Many of the Aspire laptops, such as model 8920G, have built in Blu-ray drives, 5.1 audio outputs and transflective displays. Acer was the first to include these drives in laptops. Most Aspire laptops have water-resistant screens, such as the 1410 and the 5741 Z. In 2007, Acer introduced the Gemstone series that marked a milestone in the Acer Aspire line. As with many Windows laptops, different models may have different specification in different parts of the world.
  • 2.7K
  • 20 Oct 2022
Topic Review
Grandfather Paradox
The grandfather paradox is a paradox of time travel in which inconsistencies emerge through changing the past. The name comes from the paradox's description: a person travels to the past and kills their own grandfather before the conception of their father or mother, which prevents the time traveller's existence. Despite its title, the grandfather paradox does not exclusively regard the contradiction of killing one's own grandfather to prevent one's birth. Rather, the paradox regards any action that alters the past, since there is a contradiction whenever the past becomes different from the way it was.
  • 2.7K
  • 18 Nov 2022
Topic Review
Shafa'ah
Shafa'ah (Arabic: شفاعه, "intercession"; Turkish: şefaat; Urdu: shafaat‎), in Islam is the act of pleading to God by an intimate friend of God (Muslim saint) for forgiveness. Shafa' a close meaning to Tawassul, which is the act of resorting to intimate friends of God to ask forgiveness. The word Shafa'ah is taken from shaf (شَّفْعُ) which means even as opposed to odd. The interceder, therefore, adds his own recommendation to that of petitioner so that the number of pleaders becomes even. Meaning the weak plea of the petitioner become strong by the prestige of the intercessor. Accordingly, Shafa'ah is a form of prayer to request God by the sake of those who are near to Him in order that as a member of the believing community one could hope for the intercession of the intercessors and hence deliverance from eternal damnation though not necessarily from temporary one. Shafa'ah has lately come to be among the most controversial concepts within Islamic thought. This is because some verses of the Quran negate it, if taken into consideration alone, stating that no intercession would be accepted in the day of resurrection. However, some other verses confirm it declaring that only God has the right to intercede in the next life. Finally, a third kind of verses state that some people have the authority to intercede by permission of God. Wahhabies, taking the first two kinds of these verses as true, believe that there is no intercessor but Allah, and say that whoever believes in intercession of anyone other than God is not a Muslim, rather is a polytheist (heretic). Others believe that while intercession should not be a means of emboldening people to committing sins, it should be considered as a ray of hope which lead sinners to the right path after they have wronged themselves. Belief in the intercession of Muhammad developed after his death by both Sunnis and Shiites, however among the Shiite the idea of mediation was extended to include The Twelve Imams and other intimate friends of God too.
  • 2.7K
  • 21 Nov 2022
Topic Review
Poly (Butylene Succinate) and PBS Copolyesters Degradation
The impact of plastics on the environment can be mitigated by employing biobased and/or biodegradable materials (i.e., bioplastics) instead of the traditional “commodities”. Poly (butylene succinate) (PBS) emerges as one of the most promising alternatives due to its good mechanical, thermal, and barrier properties, making it suitable for use in a wide range of applications. Nevertheless, less information regarding PBS biodegradation is available, as research is still ongoing. PBS degradation methods include hydrolytic degradation, enzymatic degradation, and biodegradation in environmental conditions, such as burial, activated sludge, and compost.
  • 2.7K
  • 22 Mar 2022
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