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Topic Review
Chemical Waste
Chemical waste is waste , that is made from chemicals that are mostly produced by large factories. Chemical waste can damage , the environment and cause health problems and as such may fall under regulations such as COSHH in the United Kingdom or the Clean Water Act and Resource Conservation and Recovery Act in the United States . In the U.S., the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA), as well as state and local regulations also regulate chemical use and disposal. The disposal and handling of radioactive waste is a particular focus for regulatory bodies due to the environmental and health risks of radiation and the challenges of safe disposal. Chemical waste may or may not be classed as hazardous waste. A chemical hazardous waste is a solid, liquid, or gaseous material that displays either a "Hazardous Characteristic" or is specifically "listed" by name as hazardous waste. There are four characteristics chemical wastes may have to be considered hazardous. These are ignitability, corrosivity, reactivity, and toxicity. This type of hazardous waste must be categorized as to its identity, constituents, and hazards so that it may be safely handled and managed. Chemical waste is a broad term and encompasses many types of materials. The Material Safety Data Sheet (MSDS), Product data sheet or Label can provide a list of constituents. These sources should state whether this chemical waste is a waste that needs special disposal.
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  • 24 Oct 2022
Topic Review
Printed and Flexible Sensors
Printed sensors fabricated on flexible platforms such as paper, plastic and textiles have been implemented for wearable applications in the biomedical, defense, food, and environmental industries.
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  • 18 Dec 2020
Topic Review
Hydrogen Production in Arctic Region
The development of markets for low-carbon energy sources requires reconsideration of issues related to extraction and use of oil and gas. Significant reserves of hydrocarbons are concentrated in Arctic territories, e.g., 30% of the world’s undiscovered natural gas reserves and 13% of oil. Associated petroleum gas, natural gas and gas condensate could be able to expand the scope of their applications. Natural gas is the main raw material for the production of hydrogen and ammonia, which are considered promising primary energy resources of the future, the oxidation of which does not release CO2. Complex components contained in associated petroleum gas and gas condensate are valuable chemical raw materials to be used in a wide range of applications.
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  • 17 Apr 2024
Topic Review
EntreComp Questionnaire for Entrepreneurship Competencies
The European Entrepreneurship Competence Framework (EntreComp) offers a comprehensive description of the knowledge, skills, and attitudes that people need to develop for an entrepreneurial mindset. Entrepreneurship competencies have usually been equated to management skills, but it is assumed that entrepreneurship activities cannot be narrowed to the management of business, since it requires a wider range of competencies. In particular, the European Council adopted the concept of entrepreneurship competencies as a set of abilities with the potential of shaping society through value creation at a social, cultural, or financial level with the sense of entrepreneurship as one of the eight key competencies necessary for a knowledge-based society.
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  • 18 Mar 2022
Biography
Longping Yuan
The father of hybrid rice, academician Longping Yuan, passed away on 22 May 2021, in Changsha, Hunan Province, China. He was born into an intellectual family in Beijing in September 1930. Due to Japanese aggression, he received his education at different primary and high schools around China from 1936 to 1949 and developed a keen interest in gardening and agronomy during this period. From Augu
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  • 29 Aug 2022
Topic Review
Hamzanama
The Hamzanama (Persian/Urdu: حمزه نامه Hamzenâme, Epic of Hamza) or Dastan-e-Amir Hamza (Persian/Urdu: داستان امیر حمزه Dâstâne Amir Hamze, "Adventures of Amir Hamza") narrates the legendary exploits of Amir Hamza, or Hamza ibn Abdul-Muttalib, an uncle of Muhammad. Most of the stories are extremely fanciful, "a continuous series of romantic interludes, threatening events, narrow escapes, and violent acts". The Hamzanama chronicles the fantastic adventures of Hamza as he and his band of heroes fight against the enemies of Islam. The stories, from a long-established oral tradition, were written down in Persian, the language of the courts of Persianate societies, in multiple volumes presumably in the era of Mahmud of Ghazni. In the West, the work is best known for the enormous illustrated manuscript commissioned by the Mughal emperor Akbar about 1562. The text augmented the story, as traditionally told in dastan performances. The dastan (storytelling tradition) about Amir Hamza persists far and wide up to Bengal and Arakan, as the Mughal Empire controlled those territories. The longest version of the Hamzanama exists in Urdu and contains 46 volumes in approximately over 45,000 pages.
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  • 24 Oct 2022
Topic Review
BBM
BBM, also known by its full name BlackBerry Messenger, was a proprietary mobile instant messenger and videotelephony application included on BlackBerry devices that allows messaging and voice calls between BlackBerry OS, BlackBerry 10, iOS, Android, and Windows Mobile users. The consumer edition for iOS and Android, BBM Consumer, was developed by Indonesian company Emtek under licence from BlackBerry Limited (formerly known as Research In Motion). The consumer edition for BlackBerry OS and BlackBerry 10, as well as the paid enterprise edition, called BBM Enterprise (BBMe, formerly known as BBM Protected), were developed fully by BlackBerry Limited and continue to function. BBM Consumer for Android and iOS was shut down on 31 May 2019, however the paid enterprise version of the software, BBMe, is still supported on these platforms. Messages sent via BBM were sent over the Internet and used the BlackBerry PIN system. In the past, many service providers allowed sign-in to BBM using a dedicated BlackBerry data plan. Exchanging messages was possible to a single person or via dedicated discussion or chat groups, which allowed multiple BlackBerry devices to communicate in a single session. In addition to offering text-based instant messages, BBM also allowed users to send pictures, voicenotes (audio recordings), files (up to 16 MB), share real time location on a map, stickers and a wide selection of emojis. Communication was possible only among BlackBerry devices, until late 2013 when BBM was released on iOS and Android systems. Over 300 million Stickers were shared. Daily, approximately 150,000 BBM Voice Calls were placed. There were more than 190 million BBM users worldwide as of 2015, and BlackBerry infrastructure handled 30 petabytes of data traffic each month by early 2013. BBM was the original "mobile-first" messaging service, and was popular for a while before it started to lose out to rivals. As of April 2016, Indonesia was the only country where BBM was the most popular messaging app – installed on 87.5% of Android devices in the country.
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  • 24 Nov 2022
Topic Review
GM B Platform
The B platform (also known as the B body) is a full-size rear-wheel drive car platform produced by General Motors from 1926 to 1996. Originally made for Oldsmobile and Buick, all of General Motors's five main makes would use it at some point. It was closely related to the original rear-wheel drive GM C and GM D platforms, and was used for convertibles, hardtops, coupes, sedans, and station wagons. With approximately 12,960,000 units built, divided across four marques, the 1965-70 B platform is the fourth best selling automobile platform in history after the Volkswagen Beetle, Ford Model T and the Lada Riva. Originally, the B platform was used for Buick and Oldsmobile products, with the first GM A platform for Chevrolet and Oakland, and the above GM C and D platforms devoted to Cadillac. During the General Motors Companion Make Program, Vikings and Marquettes were also manufactured on this platform, as were La Salles from 1936 to 1940. The B platform was used for the Pontiac Streamliner Torpedo and Streamliner, the Oldsmobile L-Series, Series 70 and Series 88, the Buick Special and Century, the LaSalle Series 50 and the Cadillac Series 60, Series 61 and Series 63. The B platform became GM's base model platform in 1958, when all existing Chevrolet products were upgraded to the B platform. For the 1959 model year, the previous A and B bodies were built on the new B platform that lasted until 1996. During this period, the B was the most modest of GM's three full-sized platforms, slotting below the upscale C and the luxury D. The A platform designation would be resurrected by GM in 1964 for a new series of intermediate-sized cars including the Chevrolet Chevelle, Pontiac Tempest, Oldsmobile Cutlass and Buick Skylark.
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  • 24 Nov 2022
Topic Review
Receptor-Like Kinases
Receptors form the crux for any biochemical signaling. Receptor-like kinases (RLKs) are conserved protein kinases in eukaryotes that establish signaling circuits to transduce information from outer plant cell membrane to the nucleus of plant cells, eventually activating processes directing growth, development, stress responses, and disease resistance. Plant RLKs share considerable homology with the receptor tyrosine kinases (RTKs) of the animal system, differing at the site of phosphorylation. Typically, RLKs have a membrane-localization signal in the amino-terminal, followed by an extracellular ligand-binding domain, a solitary membrane-spanning domain, and a cytoplasmic kinase domain. The functional characterization of ligand-binding domains of the various RLKs has demonstrated their essential role in the perception of extracellular stimuli, while its cytosolic kinase domain is usually confined to the phosphorylation of their substrates to control downstream regulatory machinery. Identification of the several ligands of RLKs, as well as a few of its immediate substrates have predominantly contributed to a better understanding of the fundamental signaling mechanisms. In the model plant Arabidopsis, several studies have indicated that multiple RLKs are involved in modulating various types of physiological roles via diverse signaling routes. Here, we summarize recent advances and provide an updated overview of transmembrane RLKs in Arabidopsis.
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  • 27 Oct 2020
Topic Review
Dera
A dera is a type of socio-religious organization in northern India . Jacob Copeman defines the deras as "monasteries or the extended residential sites of religious leaders; frequently just glossed as sect". Several deras started out as non-orthodox Sikh sects, and many of them are now centres of distinct non-Sikh religious movements. Many Deras have attracted a large number of outcast Dalits, who earlier embraced Sikhism to escape the Hindu casteism, but felt socially excluded by the Jat Sikh-dominated clerical establishment.
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  • 31 Oct 2022
Topic Review
GLP-1R Signaling
Glucagon-like peptide-1 receptor (GLP-1R) is a critical therapeutic target for type 2 diabetes mellitus (T2DM). The GLP-1R cellular signaling mechanism relevant to insulin secretion and blood glucose regulation has been extensively studied. Numerous drugs targeting GLP-1R have entered clinical treatment. Novel functional molecules with reduced side effects and enhanced therapeutic efficacy are still in high demand. 
  • 2.8K
  • 06 Feb 2023
Topic Review
Pichia kluyveri in Wine Technology
The surfaces of grapes are covered by different yeast species that are important in the first stages of the fermentation process. In recent years, non-Saccharomyces yeasts such as Torulaspora delbrueckii, Lachancea thermotolerans, Metschnikowia pulcherrima, and Pichia kluyveri have become popular with regard to winemaking and improved wine quality. For that reason, several manufacturers started to offer commercially available strains of these non-Saccharomyces species. P. kluyveri stands out, mainly due to its contribution to wine aroma, glycerol, ethanol yield, and killer factor. 
  • 2.8K
  • 18 Feb 2021
Topic Review
Primary Health Care Approach in Liberia
The World Health Organization (WHO) defines health policy as decisions, plans, and actions that are undertaken to achieve specific health care goals within a society. Primary health care (PHC), a holistic approach to health, was proposed at Alma-Ata  and has been the guiding principle for the health system rebuilding of Liberia, a post-conflict, low-income country.
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  • 18 Feb 2022
Topic Review
Geobiology
Geobiology is a field of scientific research that explores the interactions between the physical Earth and the biosphere. It is a relatively young field, and its borders are fluid. There is considerable overlap with the fields of ecology, evolutionary biology, microbiology, paleontology, and particularly soil science and biogeochemistry. Geobiology applies the principles and methods of biology, geology, and soil science to the study of the ancient history of the co-evolution of life and Earth as well as the role of life in the modern world. Geobiologic studies tend to be focused on microorganisms, and on the role that life plays in altering the chemical and physical environment of the pedosphere, which exists at the intersection of the lithosphere, atmosphere, hydrosphere and/or cryosphere. It differs from biogeochemistry in that the focus is on processes and organisms over space and time rather than on global chemical cycles. Geobiological research synthesizes the geologic record with modern biologic studies. It deals with process - how organisms affect the Earth and vice versa - as well as history - how the Earth and life have changed together. Much research is grounded in the search for fundamental understanding, but geobiology can also be applied, as in the case of microbes that clean up oil spills. Geobiology employs molecular biology, environmental microbiology, organic geochemistry, and the geologic record to investigate the evolutionary interconnectedness of life and Earth. It attempts to understand how the Earth has changed since the origin of life and what it might have been like along the way. Some definitions of geobiology even push the boundaries of this time frame - to understanding the origin of life and to the role that humans have played and will continue to play in shaping the Earth in the Anthropocene.
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  • 04 Nov 2022
Biography
Hugh Herr
Hugh Herr (born October 25, 1964) is an American rock climber, engineer, and biophysicist. The youngest of five siblings of a Mennonite family from Lancaster, Pennsylvania, Hugh Herr was a prodigy rock climber: by age eight, he had scaled the face of the 11,627-foot (3,544 m) Mount Temple in the Canadian Rockies, and by 17 he was acknowledged to be one of the best climbers in the United Stat
  • 2.8K
  • 10 Nov 2022
Topic Review
Femicides in Honduras
The femicides in Honduras is a concept which designates the murders committed against women within the Central American country of Honduras since 1990. According to the Penal Code in force until 2018, the crime of feminicide is incurred, when a man or men kill a woman for reasons of gender, with hatred and contempt for her condition as a woman. Between 2002 and 2013 3,923 women were murdered in Honduras. The number of femicides makes up 9.6% of the total number of homicides in the country. In 2013, 53 women were killed every month and, as it occurs in the rest of murders, more than 90% of the cases have gone unpunished by the law. In many of these femicides, the women are also burned, raped, and tortured beforehand. Between 2010 and 2013 the number of femicides in Honduras increased by 65%. The local national authorities have been accused of inaction by the population, given that in many cases it has not been cleared the responsibility of said felonies. There are a few government and non-government organizations that provide support to the mothers and relatives of victims of femicide. In 2015, the Honduran government allocated 30 million Honduran lempiras to the creation of a special unit in the 2016 budget for femicide investigation.
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  • 18 Nov 2022
Topic Review
The Structure and Function of Integrins
Integrins are heterodimeric transmembrane proteins that mediate adhesive connections between cells and their surroundings, including surrounding cells and the extracellular matrix (ECM). They modulate tissue mechanics and regulate intracellular signaling, including cell generation, survival, proliferation, and differentiation, and the up-regulation of integrins in tumor cells has been confirmed to be associated with tumor development, invasion, angiogenesis, metastasis, and therapeutic resistance. Thus, integrins are expected to be an effective target to improve the efficacy of tumor therapy. A variety of integrin-targeting nanodrugs have been developed to improve the distribution and penetration of drugs in tumors, thereby, improving the efficiency of clinical tumor diagnosis and treatment. 
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  • 29 Jun 2023
Topic Review
Self-Assembly Based on DNA Nanotechnology
Using DNA self-assembly, materials can be controlled at the nano scale to achieve atomic- or nano-scaled fabrication. The programmability and addressability of DNA molecules can be applied to realize the self-assembly of materials from the bottom-up, which is called DNA nanotechnology. DNA nanotechnology does not focus on the biological functions of DNA molecules, but combines them into motifs, and then assembles these motifs to form ordered two-dimensional (2D) or three-dimensional (3D) lattices. These lattices can serve as general templates to regulate the assembly of guest materials.
  • 2.8K
  • 18 May 2021
Topic Review
Melanin
Melanin (/ˈmɛlənɪn/ (listen); from Greek: μέλας, romanized: melas, lit. 'black, dark') is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against UV radiation. Melanin (neuromelanin) functions as the catalyst of all cellular functions within an organism. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research has been undertaken to investigate its efficacy in treating neurodegenerative disorders such as Parkinson's. Allomelanin and pyomelanin are two types of nitrogen-free melanin. In the human skin, melanogenesis is initiated by exposure to UV radiation, causing the skin to darken. Eumelanin is an effective absorbent of light; the pigment is able to dissipate over 99.9% of absorbed UV radiation. Because of this property, eumelanin is thought to protect skin cells from UVA and UVB radiation damage, reducing the risk of folate depletion and dermal degradation. It is considered that exposure to UV radiation is associated with increased risk of malignant melanoma, a cancer of melanocytes (melanin cells). Studies have shown a lower incidence for skin cancer in individuals with more concentrated melanin, i.e. darker skin tone.
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  • 28 Sep 2022
Topic Review
Reconnaissance Satellite
A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. The first generation type (i.e., Corona and Zenit) took photographs, then ejected canisters of photographic film which would descend back down into Earth's atmosphere. Corona capsules were retrieved in mid-air as they floated down on parachutes. Later, spacecraft had digital imaging systems and downloaded the images via encrypted radio links. In the United States, most information available is on programs that existed up to 1972, as this information has been declassified due to its age. Some information about programs prior to that time is still classified, and a small amount of information is available on subsequent missions. A few up-to-date reconnaissance satellite images have been declassified on occasion, or leaked, as in the case of KH-11 photographs which were sent to Jane's Defence Weekly in 1984.
  • 2.8K
  • 03 Nov 2022
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