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Topic Review
Education on Renewable Energy in Secondary Schools
Education is key to advancing a society that can achieve the Sustainable Development Goals (SDGs). One SDG is shifting energy consumption from fossil fuels to renewable energy (RE) sources to reduce environmental damage and prevent global warming. Awareness must be instilled among citizens at an early age (as early as secondary school) to motivate students to pursue higher education and careers in RE concepts and technologies.
  • 3.1K
  • 25 Jul 2022
Topic Review
Great Oxygenation Event
The Great Oxygenation Event, the beginning of which is commonly known in scientific media as the Great Oxidation Event (GOE, also called the Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust, Oxygen Revolution, or Great Oxidation) was the biologically induced appearance of dioxygen (O2) in Earth's atmosphere. Geological, isotopic, and chemical evidence suggests that this major environmental change happened around 2.45 billion years ago (2.45 Ga), during the Siderian period, at the beginning of the Proterozoic eon. The causes of the event remain unclear. (As of 2016), the geochemical and biomarker evidence for the development of oxygenic photosynthesis before the Great Oxidation Event has been mostly inconclusive. Oceanic cyanobacteria, which evolved into coordinated (but not multicellular or even colonial) macroscopic forms more than 2.3 billion years ago (approximately 200 million years before the GOE), are believed to have become the first microbes to produce oxygen by photosynthesis. Before the GOE, any free oxygen they produced was chemically captured by dissolved iron or by organic matter. The GOE started when oxygen produced by the cyanobacteria started escaping into the atmosphere, after other oxygen reservoirs were filled. The increased production of oxygen set Earth's original atmosphere off-balance. Free oxygen is toxic to obligate anaerobic organisms, and the rising concentrations may have destroyed most such organisms at the time. A spike in chromium contained in ancient rock-deposits formed underwater shows the accumulation had been washed off from the continental shelves. Chromium is not easily dissolved and its release from rocks would have required the presence of a powerful acid. One such acid, sulfuric acid (H2SO4), might have formed through bacterial reactions with pyrite. Mats of oxygen-producing cyanobacteria can produce a thin layer, one or two millimeters thick, of oxygenated water in an otherwise anoxic environment even under thick ice; before oxygen started accumulating in the atmosphere, these organisms would already have adapted to oxygen. Additionally, the free oxygen would have reacted with atmospheric methane, a greenhouse gas, greatly reducing its concentration and triggering the Huronian glaciation, possibly the longest episode of glaciation in Earth's history and called "snowball Earth". Eventually, the evolution of aerobic organisms that consumed oxygen established an equilibrium in its availability. Free oxygen has been an important constituent of the atmosphere ever since.
  • 3.1K
  • 10 Nov 2022
Topic Review
Quantum-classical system
A quantum-classical system is a system consisting of two interacting subsystems, one of which behaves classically, and the other requires a quantum description. 
  • 3.1K
  • 29 Oct 2020
Topic Review
CD33 Expression
Acute myeloid leukemia (AML), the most frequent acute leukemia in adults, has been historically treated with infusional cytarabine (ara-c) + daunorubicin (3 + 7) for at least 40 years. The first “target therapy” to be introduced was the monoclonal anti-CD33 gemtuzumab ozogamicin (GO) in 2004.
  • 3.1K
  • 29 Jul 2021
Biography
Saint Sava
Saint Sava (Serbian: Свети Сава / Sveti Sava, pronounced [sʋɛ̂ːtiː sǎːʋa], 1174 – 14 January 1236), known as The Enlightener, was a Serbian prince and Orthodox monk, the first Archbishop of the autocephalous Serbian Church, the founder of Serbian law, and a diplomat. Sava, born as Rastko (Serbian Cyrillic: Растко), was the youngest son of Serbian Grand Prince Stefan Nem
  • 3.1K
  • 16 Nov 2022
Topic Review
Students' Union
A students' union, student government, free student union, student senate, students' association, guild of students, or government of student body is a student organization present in many colleges, universities, and high schools. In higher education, the students' union is often accorded its own building on the campus, dedicated to social, organizational activities, representation, and academic support of the membership. In the United States, student union often only refers to a physical building owned by the university with the purpose of providing services for students without a governing body. This building is also referred to as a student activity center, although the Association of College Unions International (largely US-based) has hundreds of campus organizational members. Outside the US, student union and students' union refer to a representative body, as distinct from a student activity centre.
  • 3.1K
  • 01 Dec 2022
Topic Review
Properties of Anthocyanins
Anthocyanins are a subgroup of flavonoids, which are a prevalent and numerous class of secondary plant metabolites, that all share the C6-C3-C6 flavan or 2-phenyl-benzodihydorpyrane skeleton.
  • 3.1K
  • 14 Sep 2021
Topic Review
Hybrid Biocomposites
Bio-based composites are reinforced polymeric materials in which one of the matrix and reinforcement components or both are from bio-based origins. The biocomposite industry has recently drawn great attention for diverse applications, from household articles to automobiles. This is owing to their low cost, biodegradability, being lightweight, availability, and environmental concerns over synthetic and nonrenewable materials derived from limited resources like fossil fuel. The focus has slowly shifted from traditional biocomposite systems, including thermoplastic polymers reinforced with natural fibers, to more advanced systems called hybrid biocomposites. Hybridization of bio-based fibers/matrices and synthetic ones offers a new strategy to overcome the shortcomings of purely natural fibers or matrices. By incorporating two or more reinforcement types into a single composite, it is possible to not only maintain the advantages of both types but also alleviate some disadvantages of one type of reinforcement by another one. 
  • 3.1K
  • 13 Dec 2020
Topic Review
Layered Oxide Cathodes
Layered intercalation compounds are the dominant cathode materials for rechargeable Li-ion batteries. In this review, we discuss the topology of the layered structure and explain how the structure (1) sets the voltage slope trends among various alkali ions, (2) is critically limited to certain transition metals due to their electronic structure, and (3) controls the alkali diffusion mechanism. 
  • 3.1K
  • 17 Jun 2021
Topic Review
Nanotechnology in Horticultural Crops
Nanotechnology shows high potential in the improvement of agricultural productivity thus aiding future food security. In horticulture, maintaining quality as well as limiting the spoilage of harvested fruit and vegetables is a very challenging task. Various kinds of nanomaterials have shown high potential for increasing productivity, enhancing shelf-life, reducing post-harvest damage and improving the quality of horticultural crops. Antimicrobial nanomaterials as nanofilm on harvested products and/or on packaging materials are suitable for the storage and transportation of vegetables and fruits. Nanomaterials also increase the vitality of the cut flower. Nanofertilizers are target-specific, slow releasing and highly efficient in increasing vegetative growth, pollination and fertility in flowers, resulting in increased yield and improved product quality for fruit trees and vegetables. Formulated nanopesticides are target-specific, eco-friendly and highly efficient. Nanosensors facilitate up-to-date monitoring of growth, plant disease, and pest attack in crop plants under field conditions. These novel sensors are used to precisely identify the soil moisture, humidity, population of crop pests, pesticide residues and figure out nutrient requirements.  
  • 3.1K
  • 08 Oct 2021
Topic Review
Bon Festival
Obon (お盆) or just Bon (盆) is a Japanese Buddhist custom to honor the spirits of one's ancestors. This Buddhist–Confucian custom has evolved into a family reunion holiday during which people return to ancestral family places and visit and clean their ancestors' graves when the spirits of ancestors are supposed to revisit the household altars. It has been celebrated in Japan for more than 500 years and traditionally includes a dance, known as Bon Odori. The festival of Obon lasts for three days; however, its starting date varies within different regions of Japan. When the lunar calendar was changed to the Gregorian calendar at the beginning of the Meiji era, the localities in Japan responded differently, which resulted in three different times of Obon. Shichigatsu Bon (Bon in July) is based on the solar calendar and is celebrated around the 15th of July in eastern Japan (Kantō region such as Tokyo, Yokohama and the Tōhoku region), coinciding with Chūgen. Hachigatsu Bon (Bon in August), based on the lunar calendar, is celebrated around the 15th of August and is the most commonly celebrated time. Kyū Bon (Old Bon) is celebrated on the 15th day of the ninth month of the lunar calendar, and so differs each year, which appears between August 8 and September 7. One exception was in 2008 and 2019, when the solar and lunar calendar matched, and so Hachigatsu Bon and Kyū Bon were celebrated on the same day. Kyū Bon is celebrated in areas such as the northern part of the Kantō region, Chūgoku region, Shikoku, and Okinawa Prefecture. These three festival days are not listed as public holidays, but it is customary for people to be given leave.
  • 3.1K
  • 23 Oct 2022
Topic Review
Progress of 2D Semiconductor-based photocatalysts
A complete view of basic principles and mechanisms with regard to improving the structure stability, physical and chemical properties of the low dimensional semiconductor-based photocatalysts is presented here. Various 2D semiconductor-based photocatalysts show a high electrochemical property and photocatalytic performance due to their ultrathin character, high specific surface area with more activity sites, tunable bandgap to absorb sunlight and versatile options in structural assembly with other nanosheets. At present, most photocatalysts still need rare or expensive noble metals to improve the photocatalytic activity, which inhibits their commercial-scale application extremely. Thus, developing less costly, earth-abundant semiconductor-based photocatalysts with the efficient conversion of sunlight energy remains the primary challenge. A concise overview of different types of 2D semiconductor-mediated photocatalysts is given to figure out the advantages and disadvantages for mentioned semiconductor-based photocatalysis, including the structural property and stability, synthesize method, electrochemical property, and optical properties for H2/O2 production half-reaction along with overall water splitting.
  • 3.1K
  • 21 Oct 2020
Topic Review
Chaldean Oracles
The Chaldean Oracles are a set of spiritual and philosophical texts widely used by Neoplatonist philosophers from the 3rd to the 6th century C.E. While the original texts have been lost, they have survived in the form of fragments consisting mainly of quotes and commentary by Neoplatonist writers. They were likely to have originally formed a single mystery-poem, which may have been in part compiled, in part received via trance, by Julian the Chaldean, or more likely, his son, Julian the Theurgist in the 2nd century C.E. Later Neoplatonists, such as Iamblichus and Proclus, rated them highly. The 4th-century Emperor Julian (not to be confused with Julian the Chaldean or Julian the Theurgist) suggests in his Hymn to the Magna Mater that he was an initiate of the God of the Seven Rays, and was an adept of its teachings. When Christian Church Fathers or other Late Antiquity writers credit "the Chaldeans", they are probably referring to this tradition. An analysis of the Chaldean Oracles demonstrates an inspiration for contemporary gnostic teachings: fiery emanations initiate from the transcendental First Paternal Intellect, from whom the Second Intellect, the Demiurge comprehends the cosmos as well as himself. Within the First Intellect, a female Power, designated Hecate, is, like Sophia, the mediating World-Soul. At the base of all lies created Matter, made by the Demiurgic Intellect. The matter farthest from the Highest God (First Father / Intellect) was considered a dense shell from which the enlightened soul must emerge, shedding its bodily garments. A combination of ascetic conduct and correct ritual are recommended to free the soul from the confines of matter and limitations, and to defend it against the demonic powers lurking in some of the realms between Gods and mortals.
  • 3.1K
  • 14 Nov 2022
Topic Review
Literature
This is a list of encyclopedias as well as encyclopedic and biographical dictionaries published on the subject of literature in any language.
  • 3.1K
  • 28 Apr 2023
Topic Review
Photolyase
Photolyase is a protein that has various functions, among which is the repair of DNA damaged from exposure to UV rays from the sun.
  • 3.1K
  • 30 Sep 2022
Topic Review
Conductive Fibers
As one of the most impressive materials for wearable sensors, conductive fibers can be made from a variety of raw sources via diverse preparation strategies.
  • 3.1K
  • 28 Apr 2022
Topic Review
The Interaction between Urban and Rural Areas
The relationships and interactions between rural and urban spaces have long been of interest to territorial sciences. However, approaches to these issues have evolved in line with the changing characteristics of the two types of territories, reflecting new relationships and structures. 
  • 3.1K
  • 26 Aug 2022
Topic Review
Polyphenylsulfone Membrane
Polyphenylsulfone (PPSU) membranes are of fundamental importance for many applications such as water treatment, gas separation, energy, electronics, and biomedicine, due to their low cost, controlled crystallinity, chemical, thermal, and mechanical stability. Numerous research studies have shown that modifying surface properties of PPSU membranes influences their stability and functionality. Therefore, the modification of the PPSU membrane surface is a pressing issue for both research and industrial communities.
  • 3.1K
  • 10 Mar 2022
Topic Review
Breastfeeding
Breastfeeding, also known as nursing, is the feeding of babies and young children with milk from a woman's breast. Health professionals recommend that breastfeeding begin within the first hour of a baby's life and continue as often and as much as the baby wants. During the first few weeks of life babies may nurse roughly every two to three hours and the duration of a feeding is usually ten to fifteen minutes on each breast. Older children feed less often. Mothers may pump milk so that it can be used later when breastfeeding is not possible. Breastfeeding has a number of benefits to both mother and baby, which infant formula lacks. Deaths of an estimated 820,000 children under the age of five could be prevented globally every year with increased breastfeeding. Breastfeeding decreases the risk of respiratory tract infections and diarrhea, both in developing and developed countries. Other benefits include lower risks of asthma, food allergies, type 1 diabetes, and leukemia. Breastfeeding may also improve cognitive development and decrease the risk of obesity in adulthood. Mothers may feel pressure to breastfeed, but in the developed world children generally grow up normally when bottle fed. Benefits for the mother include less blood loss following delivery, better uterus shrinkage, and less postpartum depression. Breastfeeding delays the return of menstruation and fertility, a phenomenon known as lactational amenorrhea. Long term benefits for the mother include decreased risk of breast cancer, cardiovascular disease, and rheumatoid arthritis. Breastfeeding is less expensive than infant formula. Health organizations, including the World Health Organization (WHO), recommend breastfeeding exclusively for six months. This means that no other foods or drinks other than possibly vitamin D are typically given. After the introduction of foods at six months of age, recommendations include continued breastfeeding until one to two years of age or more. Globally about 38% of infants are only breastfed during their first six months of life. In the United States, about 75% of women begin breastfeeding and about 13% only breastfeed until the age of six months. Medical conditions that do not allow breastfeeding are rare. Mothers who take certain recreational drugs and medications should not breastfeed. Smoking, limited amounts of alcohol, or coffee are not reasons to avoid breastfeeding.
  • 3.1K
  • 11 Nov 2022
Topic Review
Exercise influence on calcium-phosphorous metabolism
Exercise perturbs homeostasis, alters the levels of circulating mediators and hormones, and increases the demand by skeletal muscles and other vital organs for energy substrates. Exercise also affects bone and mineral metabolism, particularly calcium and phosphate, both of which are essential for muscle contraction, neuromuscular signaling, biosynthesis of adenosine triphosphate (ATP), and other energy substrates. Parathyroid hormone (PTH) is involved in the regulation of calcium and phosphate homeostasis. Understanding the e ects of exercise on PTH secretion is fundamental for appreciating how the body adapts to exercise.
  • 3.1K
  • 26 Aug 2020
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