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Topic Review
Hole-Transporting Layer in Perovskite Solar Cells
Organic-inorganic halide perovskite solar cells (PSCs) have received particular attention because of the high-power conversion efficiencies (PCEs), facile fabrication route and low cost. The hole-transporting layer (HTL) play an important role in PSCs to effectively extract holes from the perovskite film and to transport holes to the metal electrode in normal PSCs. 
  • 5.1K
  • 09 Aug 2022
Topic Review
Ural–Altaic Languages
Ural–Altaic, Uralo-Altaic or Uraltaic is a linguistic convergence zone and former language-family proposal uniting the Uralic and the Altaic (in the narrow sense) languages. It is generally now agreed that even the Altaic languages most likely do not share a common descent: the similarities among Turkic, Mongolic and Tungusic are better explained by diffusion and borrowing. The term continues to be used for the central Eurasian typological, grammatical and lexical convergence zone. Indeed, "Ural-Altaic" may be preferable to "Altaic" in this sense. For example, J. Janhunen states that "speaking of 'Altaic' instead of 'Ural-Altaic' is a misconception, for there are no areal or typological features that are specific to 'Altaic' without Uralic." Originally suggested in the 18th century, the genealogical and racial hypotheses remained debated into the mid-20th century, often with disagreements exacerbated by pan-nationalist agendas. It had many proponents in Britain. Since the 1960s, the proposed language family has been widely rejected. A relationship between the Altaic, Indo-European and Uralic families was revived in the context of the Nostratic hypothesis, which was popular for a time, with for example Allan Bomhard treating Uralic, Altaic and Indo-European as coordinate branches. However, Nostratic too is now mostly rejected.
  • 5.1K
  • 31 Oct 2022
Topic Review
Fluid Catalytic Cracking
The fluid catalytic cracking (FCC) process is an alternative olefin production technology, with lower CO2 emission and higher energy-saving.
  • 5.1K
  • 23 Feb 2021
Topic Review
Blading (Professional Wrestling)
In professional wrestling, blading is the practice of intentionally cutting oneself to provoke bleeding. It is also known as "juicing", "gigging", or "getting color". Similarly, a blade is an object used for blading and a bladejob is a specific act of blading. The act is usually done a good length into the match as the blood will mix with the flowing sweat to make it look like much more blood is flowing from the wound than there actually is. The preferred area for blading is usually the forehead, as scalp wounds bleed profusely and heal easily. Legitimate, unplanned bleeding which occurs outside the storyline is called "juicing the hard way".
  • 5.1K
  • 24 Oct 2022
Topic Review
Types of Aluminium Matrix Composites
Al alloy has very attractive properties required in the production of aerospace, automotive, electrical and electronic, sports and recreational components/equipment. Its low strength and low wear resistance have challenged its applications in some other critical industrial utilities. Nonetheless, the invention of metal composites has removed such barriers. The addition of one or more reinforcements to Al has helped in the creation of aluminium matrix composites (AMCs), which has not only increased the global utilization of Al alloy, but has been a major source of global revenue and job. 
  • 5.1K
  • 20 Oct 2022
Biography
Pandurang Shastri Athavale
Pandurang Shastri Athavale (19 October 1920 – 25 October 2003), also known as Dadaji, which literally translates as "elder brother" in Marathi, was an Indian activist, philosopher, spiritual leader, social revolutionary,[1] and religion reformist, who founded the Swadhyaya Parivar (Swadhyaya Family) in 1954.[2] Swadhyaya is a self-study process based on the Bhagavad Gita which has spread acros
  • 5.1K
  • 02 Dec 2022
Topic Review
Closed Graph
In mathematics, particularly in functional analysis and topology, closed graph is a property of functions. A function f : X → Y between topological spaces has a closed graph if its graph is a closed subset of the product space X × Y. A related property is open graph. This property is studied because there are many theorems, known as closed graph theorems, giving conditions under which a function with a closed graph is necessarily continuous. One particularly well-known class of closed graph theorems are the closed graph theorems in functional analysis.
  • 5.1K
  • 18 Oct 2022
Topic Review
Energy Technology
Energy technology is an interdisciplinary engineering science having to do with the efficient, safe, environmentally friendly, and economical extraction, conversion, transportation, storage, and use of energy, targeted towards yielding high efficiency whilst skirting side effects on humans, nature, and the environment. For people, energy is an overwhelming need, and as a scarce resource, it has been an underlying cause of political conflicts and wars. The gathering and use of energy resources can be harmful to local ecosystems and may have global outcomes. Energy is also the capacity to do work. We can get energy from food. Energy can be of different forms such as kinetic, potential, mechanical, heat, light etc. Energy is required for individuals and the whole society for lighting, heating, cooking, running, industries, operating transportation and so forth. Basically there are two types of energy depending on the source s they are; 1.Renewable Energy Sources 2.Non-Renewable Energy Sources
  • 5.1K
  • 11 Nov 2022
Topic Review
Effects of Creatine Supplementation on Brain Function
Creatine, a nitrogenous organic compound derived from reactions involving the amino acids arginine, glycine, and methionine, is important for resynthesizing ATP, particularly during times of increased metabolic demand (e.g., sleep deprivation, mental health conditions, or neurological diseases). Creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. 
  • 5.1K
  • 09 Jun 2022
Topic Review Peer Reviewed
Helen Nemanjić (1250–1314)
Queen Helen Nemanjić (?–Brnjaci near Zubin Potok, February 8, 1314) was a Serbian medieval queen and consort of King Stefan Uroš I (r. 1243–1276), the fifth ruler of the Serbian Nemanide dynasty. She was the mother of the kings Stefan Dragutin and Stefan Uroš II Milutin. Today, she is known as Helen of Anjou (Jelena Anžujska in Serbian) although her real name was most probably Heleni Angelina (Ελένη Aγγελίνα). She was the founder of the Serbian Orthodox monastery of Gradac as well as four Franciscan abbeys in Kotor, Bar, Ulcinj, and Shkodër. Together with her sons, Kings Stefan Dragutin and Stefan Uroš II Milutin she helpedrenovation of Benedictine abbey of Sts. Sergius and Bacchus near Shkodër on Boyana river in present-day Albania. After the death of her husband, she ruled Zeta and Travunija until 1306. She was known for her religious tolerance and charitable and educational endeavors. She was elevated to sainthood by the Serbian Orthodox Church. Along with Empress Helen, the wife of Serbian Emperor Stefan Uroš IV Dušan, Queen Helen was the most frequently painted woman of Serbian medieval art. Six of her portraits can be found in the monumental painting ensembles of the Serbian medieval monasteries of Sopoćani, Gradac, Arilje, Đurđevi Stupovi (Pillars of St. George), and Gračanica, as well as on two icons and one seal. Queen Helen is also the only female Serbian medieval ruler whose vita was included in the famous collection of the “Lives of Serbian Kings and Archbishops” by Archbishop Danilo II, a prominent church leader, warrior, and writer. 
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  • 13 Apr 2022
Topic Review
Myeloid-Derived Suppressor Cells
Myeloid-derived suppressor cells (MDSCs) are heterogeneous cells derived from bone marrow. They are precursors of dendritic cells, macrophages and/or granulocytes. They have the ability to significantly inhibit immune cell responses.
  • 5.1K
  • 27 Oct 2020
Topic Review
Humic Substances
Humic substances are a very important part of our soil.  The topic is description of the structure of humic substances using NMR.  The NMR part is divided into two parts, liquid and solid state NMR.  The assignment of NMR spectra are discussed and the structural elements that can be deduced from the spectral information.  Principal Component Analysis is used as a tool to categorize the information.  Structural models are discussed.
  • 5.1K
  • 16 Jul 2024
Topic Review
Application of Analog-to-Digital Converter in Ultrasonic Imaging System
The ADC, a bridge between the analog world and the digital world, converts the analog signals to digital so that the analog signal in the baseband can be processed by the back-end computer or microprocessor.
  • 5.1K
  • 17 Jan 2022
Topic Review
Internal Monologue
An internal monologue, also called self-talk, inner speech, inner discourse or internal discourse, is a person's inner voice which provides a running verbal monologue of thoughts while they are conscious. It is usually tied to a person's sense of self. It is particularly important in planning, problem solving, self-reflection, self-image, critical thinking, emotions, and subvocalization (reading in one's head). As a result, it is relevant to a number of mental disorders, such as depression, and treatments like cognitive behavioural therapy which seek to alleviate symptoms by providing strategies to regulate cognitive behaviour. It may reflect both conscious and subconscious beliefs. In some cases people may think of inner speech as coming from an external source, as with schizophrenic auditory hallucinations. Additionally, not everyone has a verbal internal monologue (see § Absence of an internal monologue). The looser flow of thoughts and experiences, verbal or not, is called a stream of consciousness, which can also refer to a related technique in literature. In a theory of child development formulated by Lev Vygotsky, inner speech has a precursor in private speech (talking to oneself) at a young age.
  • 5.1K
  • 15 Nov 2022
Topic Review
Effects of Global Warming
The effects of global warming or climate damage include far-reaching and long-lasting changes to the natural environment, to ecosystems and human societies caused directly or indirectly by human emissions of greenhouse gases. It also includes the economic and social changes which stem from living in a warmer world. Human caused climate change is one of the threats to sustainability. Many physical impacts of global warming are already visible, including extreme weather events, glacier retreat, changes in the timing of seasonal events (e.g., earlier flowering of plants), sea level rise, and declines in Arctic sea ice extent. The future impact of global warming depends on the extent to which nations implement prevention efforts and reduce greenhouse gas emissions. Ocean acidification is not a consequence of global warming, but instead has the same cause: increasing atmospheric carbon dioxide. Climate change has already impacted ecosystems and humans as well. In combination with climate variability, it makes food insecurity worse in many places and puts pressure on fresh water supply. This in combination with extreme weather events, leads to negative effects on human health. Rising temperatures threaten development because of negative effects on economic growth in developing countries. The social impact of climate change will be further affected by society's efforts to prepare and adapt. Global warming already contributes to migration in different parts of the world. Near-term climate change policies significantly affect long-term climate change impacts. Stringent mitigation policies might be able to limit global warming (in 2100) to around 2 °C or below, relative to pre-industrial levels. Without mitigation, increased energy demand and extensive use of fossil fuels might lead to global warming of around 4 °C. Higher magnitudes of global warming would be more difficult to adapt to, and would increase the risk of negative impacts.
  • 5.1K
  • 01 Nov 2022
Topic Review
Chi-Square Distribution
In probability theory and statistics, the chi-square distribution (also chi-squared or χ2-distribution) with k degrees of freedom is the distribution of a sum of the squares of k independent standard normal random variables. The chi-square distribution is a special case of the gamma distribution and is one of the most widely used probability distributions in inferential statistics, notably in hypothesis testing and in construction of confidence intervals. This distribution is sometimes called the central chi-square distribution, a special case of the more general noncentral chi-square distribution. The chi-square distribution is used in the common chi-square tests for goodness of fit of an observed distribution to a theoretical one, the independence of two criteria of classification of qualitative data, and in confidence interval estimation for a population standard deviation of a normal distribution from a sample standard deviation. Many other statistical tests also use this distribution, such as Friedman's analysis of variance by ranks.
  • 5.1K
  • 11 Nov 2022
Topic Review
Naturopathy
Naturopathy, or naturopathic medicine, is a form of alternative medicine. It employs an array of pseudoscientific practices branded as "natural", "non-invasive", or promoting "self-healing". The practices of naturopaths, the practitioners of naturopathic medicine, vary widely and are difficult to generalize. Treatments range from outright quackery, like homeopathy, to widely accepted practices like psychotherapy. The ideology and methods of naturopathy are based on vitalism and folk medicine rather than evidence-based medicine (EBM), although some practitioners may use techniques supported by EBM. Naturopathic practitioners commonly recommend against following modern medical practices, including but not limited to medical testing, drugs, vaccinations, and surgery. Instead, naturopathic practice relies on unscientific notions, often leading naturopaths to diagnoses and treatments that have no factual merit. Naturopathy is considered by the medical profession to be ineffective and harmful, raising ethical issues about its practice. In addition to condemnations and criticism from the medical community, such as the American Cancer Society, naturopaths have repeatedly been denounced as and accused of being charlatans and practicing quackery. Naturopaths are known for their frequent campaigning for legal recognition in the United States . It is illegal in two U.S. states and tightly regulated in many others. Some states have lax regulations, however, and may allow naturopaths to perform minor surgery or even prescribe drugs. While some schools exist for naturopaths, and some jurisdictions allow such practitioners to call themselves doctors, the lack of accreditation and scientific medical training means they lack the competency of true medical doctors.
  • 5.1K
  • 24 Oct 2022
Topic Review
Borderland
The word “borderland” has many meanings; however, it is most often considered from the geographical and sociological, or, in other words, spatial and cultural perspective. The borderland is an area or a territory located near the border or far away from the centre. Within the borderland, socio-cultural contact takes place between various nations or ethnic groups. This is where the “new people and their culture” are formed. A borderland is sometimes precisely delimited, e.g., based on natural objects such as rivers or mountain ranges, or on administrative attributes. It is, however, most frequently determined on the basis of settlement geography. Its actual area and range are determined by migrations, colonisation, and cultural diversity of its inhabitants .
  • 5.1K
  • 19 Jul 2021
Topic Review
Frame of Reference
In physics, a frame of reference (or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix (locate and orient) the coordinate system and standardize measurements within that frame. For n dimensions, n + 1 reference points are sufficient to fully define a reference frame. Using rectangular (Cartesian) coordinates, a reference frame may be defined with a reference point at the origin and a reference point at one unit distance along each of the n coordinate axes. In Einsteinian relativity, reference frames are used to specify the relationship between a moving observer and the phenomenon or phenomena under observation. In this context, the phrase often becomes "observational frame of reference" (or "observational reference frame"), which implies that the observer is at rest in the frame, although not necessarily located at its origin. A relativistic reference frame includes (or implies) the coordinate time, which does not correspond across different frames moving relatively to each other. The situation thus differs from Galilean relativity, where all possible coordinate times are essentially equivalent.
  • 5.1K
  • 21 Oct 2022
Topic Review
Descendants of the Bounty Mutineers
The descendants of the Bounty mutineers and their Tahitian consorts include the modern-day Pitcairn Islanders as well as a little less than half of the population of Norfolk Island. Their descendants also live in New Zealand, Australia, and the United States. Because of the scarcity of people on the island, many of the mutineers' children and grandchildren intermarried, with some marrying cousins and second cousins. Occasionally a new person would arrive on the island bringing with them a new surname (like the American Samuel Russell Warren, whose descendants still live on the island today).
  • 5.1K
  • 25 Oct 2022
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