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Topic Review
Water Quality Degradation
Water quality degradation is happened through the natural processes that influence the surface water and groundwater quality by various sources such as climate changes, natural disasters, geological factors, soil-matrix, and hyporheic exchange. Water could also be contaminated by anthropogenic factors. Anthropogenic pollutants are substances caused by human actions, mostly resulting from land-use practices. 
  • 17.2K
  • 05 Feb 2022
Topic Review
6061 Aluminium Alloy
6061 (Unified Numbering System (UNS) designation A96061) is a precipitation-hardened aluminium alloy, containing magnesium and silicon as its major alloying elements. Originally called "Alloy 61S", it was developed in 1935. It has good mechanical properties, exhibits good weldability, and is very commonly extruded (second in popularity only to 6063). It is one of the most common alloys of aluminum for general-purpose use. It is commonly available in pre-tempered grades such as 6061-O (annealed), tempered grades such as 6061-T6 (solutionized and artificially aged) and 6061-T651 (solutionized, stress-relieved stretched and artificially aged).
  • 17.2K
  • 22 Nov 2022
Topic Review
Hydrogen Storage and Transportation
In the current hydrocarbon economy, transportation is fueled primarily by petroleum. Burning of hydrocarbon fuels emits carbon dioxide and other pollutants. The supply of economically usable hydrocarbon resources in the world is limited, and the demand of hydrocarbon fuels is increasing, particularly in China, India and other countries. Proponents of a world-scale hydrogen economy argue that hydrogen can be environmentally cleaner source of energy to end-users, particularly in transportation applications, without release of pollutants (such as particulate matter) or carbon dioxide at the point of end use. A recent analysis asserted that “most of the hydrogen supply chain pathways would release significantly less carbon dioxide into the atmosphere than would gasoline used in hybrid electric vehicles” and that significant reductions in carbon dioxide emissions would be possible if carbon capture or carbon sequestration methods were utilized at the site od energy or hydrogen production. Hydrogen storage can be distributed continuously in pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system also pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels. Furthermore, hydrogen is regenerative and environment friendly. But two difficulties with hydrogen are that hydrogen is just an energy carrier and has a low critical temperature of 35 K, i.e., hydrogen is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific surface area (at T< 100K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent and ionic compounds (at ambient pressure), oxidation of reactive metals e.g., Li, Na, Mg, Al, Zn with water. These metals easily react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can be thermally reduced to the metals in a solar furnace. In conclusion, routes for the transmission and storage of hydrogen for chemical processes, and hydrogen-based energy systems are increasing their establishment. Here, these routes are described, considering their attractions and difficulties.
  • 17.1K
  • 18 Jun 2021
Topic Review
Magnoliophyta
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (/ˌændʒiəˈspɜːrmiː/), commonly called angiosperms. The term "angiosperm" is derived from the Greek words angeion ('container, vessel') and sperma ('seed'), and refers to those plants that produce their seeds enclosed within a fruit. They are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. Angiosperms were formerly called Magnoliophyta (/mæɡˌnoʊliˈɒfətə, -əˈfaɪtə/). Like gymnosperms, angiosperms are seed-producing plants. They are distinguished from gymnosperms by characteristics including flowers, endosperm within their seeds, and the production of fruits that contain the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous, over 300 million years ago. The closest fossil relatives of flowering plants are uncertain and contentious. The earliest angiosperm fossils are in the form of pollen around 134 million years ago during the Early Cretaceous. Over the course of the Cretaceous, angiosperms explosively diversified, becoming the dominant group of plants across the planet by the end of the period, corresponding with the decline and extinction of previously widespread gymnosperm groups. The origin and diversification of the angiosperms is often known as "Darwin's abominable mystery".
  • 17.1K
  • 28 Nov 2022
Topic Review
Adolescents Malnutrition
Adolescents are young individuals that are between the ages of 10 and 19 years old.  Malnutrition refers to deficiencies, excesses or imbalances in an individual intake of energy and/or nutrients 
  • 17.1K
  • 16 Jul 2021
Topic Review
Smart Clothing
Smart clothing can be defined as the intelligent system that senses and reacts to the changes and stimuli of the environment and the wearer’s conditions, such as electrical, thermal and magnetic ones. Smart clothing has various functions (e.g., protection, temperature regulation, monitoring, entertainment, expression of personality, etc.) and embodies many features (e.g., efficient, intelligent, computable, etc.), combining cutting-edge technologies in related fields such as electronic information, sensors and materials. Smart clothing has emerged to meet consumers’ personalized needs in healthcare, work, entertainment, etc., and has rapidly become a hotspot in the clothing industry and research field. However, as smart clothing gets popular, sustainability issues are becoming increasingly prominent during its development and circulation. 
  • 17.1K
  • 19 Apr 2022
Topic Review
Davidic Line
The Davidic line or House of David (Hebrew: בית דוד‎, romanized: Beit David) refers to the lineage of the Israelite king David through texts in the Hebrew Bible, the New Testament, and through the succeeding centuries. According to the Bible, David, of the Tribe of Judah, was the third king of the United Monarchy of Israel and Judah. He was later succeeded by his son, Solomon. After Solomon's death, the ten northern tribes rejected the Davidic line, refusing to accept Solomon's son, Rehoboam, and instead chose as king Jeroboam and formed the northern Kingdom of Israel. The southern tribes of Judah and Benjamin remained loyal to the House of David, and this kingdom came to be known as the Kingdom of Judah. All subsequent kings of Judah, except Athaliah, are said to be direct descendants of David. The kingdom fell to the Neo-Babylonian Empire in 587/6 BCE. The Hasmoneans, who established their own monarchy in Judea in the 2nd century BCE, were not considered connected to the Davidic line nor to the Tribe of Judah. In Judaism and Christianity, the Davidic Line is the bloodline from which the Hebrew Messiah has a patrilineal descent. In Jewish eschatology, the Messiah is a future Jewish king from the Davidic line, who is expected to rule the Jewish people during the Messianic Age and world to come. The Christian gospels claim that Jesus descends from the Davidic line and is therefore the legitimate Hebrew Messiah. The New Testament books of Matthew and Luke give two different accounts of the genealogy of Jesus that trace back to David.
  • 17.1K
  • 02 Dec 2022
Topic Review
Ali in the Quran
The majority of Islamic commentators do not believe that Ali ibn Abu Talib (Arabic: عَـلِي ابْـن أَبُـو طَـالِـب) is mentioned explicitly in the Quran. However, Shi'ite scholars and some Sunni scholars interpret many Quranic verses as referring to Ali. Shi'ite scholars also believe other Imams have been referred in the Quran. They believe Imams are referred to as "the signs of Allah, the way, the straight path, the light of Allah, the inheritors of the Book, the people of knowledge, the holders of authority and other such designations," Shi'ite sources state, Muhammad al-Baqir answers: "Allah revealed Salat to his Prophet but never said of three or four Rakats, revealed Zakat but did not mention to its details, revealed Hajj but did not count its Tawaf and the Prophet interpreted their details. Allah revealed this verse and Prophet said this verse is about Ali, Hasan, Husayn and the other Twelve Imams." Shi'ite scholars, thus, have argued that a quarter of Qur'anic verses are stating the station of imams. Such a view is rejected by Sunni scholars, who argue that some of these verses instead refer to the Quraysh or Muhammad's wives.
  • 17.1K
  • 14 Oct 2022
Topic Review
Solar Power Plants in Iran
The world’s electricity generation has increased with renewable energy technologies such as solar (solar power plant), wind energy (wind turbines), heat energy, and even ocean waves. Iran is in the best condition to receive solar radiation due to its proximity to the equator (25.2969° N). In 2020, Iran was able to supply only 900 MW (about 480 solar power plants and 420 MW home solar power plants) of its electricity demand from solar energy, which is very low compared to the global average. Yazd, Fars, and Kerman provinces are in the top ranks of Iran, with the production of approximately 68, 58, and 47 MW using solar energy, respectively. Iran also has a large area of vacant land for the construction of solar power plants.
  • 17.0K
  • 07 Jan 2022
Topic Review
Understanding Sexual Agency
Debates on human agency, not least female and sexual agency, have permeated the social scientific literature and health educational practice during multiple decades now. This article provides a review of recent agency debates, illustrating how criticisms of traditional conceptions of (sexual) agency have led to a notable diversification of the concept. We propose a comprehensive, inclusive description of sexual agency, focusing on the navigation of goals and desires in the wider structural context, and acknowledging the many forms sexual agency may take. We argue there is no simple relation between sexual agency and sexual health. We propose the following description: Sexual agency refers to a continuum of dynamic, everyday, situated modalities of action related to sexuality in which agents navigate (contrarieties between) personal goals, desires and preferences on the one, and personal living conditions, normative expectations and the wider structural context on the other hand. A diversity of internal (e.g. self-identification) and/or external goals (e.g. maintain social relationships or challenge the status quo) motivate and direct sexually agentic behavior. Sexual agency may aim for change as well as for endurance, continuity and stability. It may be overt or tacit. It varies with individual (e.g. temporal orientation) as well as situational variables (e.g. novelty). Sexual agency may reproduce but also resist and renegotiate (aspects of) prevailing norms and the status quo. There is no simple relation between sexual agency and sexual health or well-being. Modalities of action as well as the constructiveness of their (multiple) effects always depend on personal frames of reference as well as on the opportunities and restrictions provided by the (immediate and distant) personal and structural context, including moral and ideological frameworks and dominant sexual stories.
  • 17.0K
  • 21 Oct 2021
Topic Review
Impact of Nanotechnology
The impact of nanotechnology extends from its medical, ethical, mental, legal and environmental applications, to fields such as engineering, biology, chemistry, computing, materials science, and communications. Major benefits of nanotechnology include improved manufacturing methods, water purification systems, energy systems, physical enhancement, nanomedicine, better food production methods, nutrition and large-scale infrastructure auto-fabrication. Nanotechnology's reduced size may allow for automation of tasks which were previously inaccessible due to physical restrictions, which in turn may reduce labor, land, or maintenance requirements placed on humans. Potential risks include environmental, health, and safety issues; transitional effects such as displacement of traditional industries as the products of nanotechnology become dominant, which are of concern to privacy rights advocates. These may be particularly important if potential negative effects of nanoparticles are overlooked. Whether nanotechnology merits special government regulation is a controversial issue. Regulatory bodies such as the United States Environmental Protection Agency and the Health and Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles. The organic food sector has been the first to act with the regulated exclusion of engineered nanoparticles from certified organic produce, firstly in Australia and the UK, and more recently in Canada , as well as for all food certified to Demeter International standards
  • 16.9K
  • 18 Oct 2022
Topic Review
Classification of Green Solvents
Green solvents, such as bio-based (derived from renewable sources), water-based (dissolved in water), supercritical fluids (above their critical point), and deep eutectic solvents (formed by mixing two or more components), offer alternatives to conventional organic solvents for bio-oil extraction. These solvents are characterized by being non-toxic, non-volatile, recyclable, and biodegradable.
  • 16.9K
  • 16 Aug 2023
Topic Review
Boarhounds
Boarhounds are hunting dogs bred for hunting wild boar. The most commonly used for this purpose are hounds, dachshunds or terriers, but pointers, spitz or retrievers can also be used. The dog should be courageous, persistent, passionate, disciplined, sharp and obedient. Hunting in this group of dogs can be carried out individually and for such breeds are used small and collective breeds as well as medium and large breeds of dogs.
  • 16.9K
  • 16 Jun 2021
Topic Review
Relative Hour (Jewish Law)
Relative hour (Hebrew singular: shaʿah zǝmanit / שעה זמנית; plural: shaʿot - zǝmaniyot / שעות זמניות), sometimes called halachic hour, seasonal hour and variable hour, is a term used in rabbinic Jewish law that assigns 12 hours to each day and 12 hours to each night, all throughout the year. A relative hour has no fixed radical, but changes with the length of each day - depending on summer (when the days are long and the nights are short), and on winter (when the days are short and the nights are long). Even so, in all seasons a day is always divided into 12 hours, and a night is always divided into 12 hours, which inevitably makes for a longer hour or a shorter hour. All of the hours mentioned by the Sages in either the Mishnah or Talmud, or in other rabbinic writings, refer strictly to relative hours. Another feature of this ancient practice is that, unlike the standard modern 12-hour clock that assigns 12 o'clock pm for noon time, in the ancient Jewish tradition noon time was always the sixth hour of the day, whereas the first hour began with the break of dawn, by most exponents of Jewish law, and with sunrise by the Vilna Gaon and Rabbi Hai Gaon. 12:o'clock am (midnight) was also the sixth hour of the night, whereas the first hour of the night began when the first three stars appeared in the night sky.
  • 16.9K
  • 19 Oct 2022
Topic Review
The Evolution of Computers
This research explores the evolution of computing from the earliest mechanical devices to the latest cutting-edge technologies. It covers the development of electronic computers in the 1940s and their impact on military, scientific, and business operations. Mainframe computers of the 1950s and 1960s are discussed, including their role in business computing and financial innovation. The personal computer revolution of the 1970s and the rise of mobile computing in the 1980s and 2000s are also examined. The research concludes with a look at the latest developments in computing, including quantum computing and artificial intelligence, and the potential impact of these technologies on society. It emphasizes the importance of working together to address the challenges of emerging technologies and ensuring their ethical and equitable use.
  • 16.9K
  • 22 May 2023
Biography
René Sotelo
René Sotelo (6 November 1962) is a Venezuelan robotic surgeon, urologist-oncologist and university professor.[1][2] Sotelo received his medical degree from Central University of Venezuela[3] and his residency in General Surgery and Urology was at Domingo Luciani Hospital, Venezuela. He completed fellowship in Urologic Oncology at the Hospital Padre Machado in Caracas, Venezuela; training in
  • 16.9K
  • 18 Nov 2022
Topic Review
List of Anatomy Mnemonics
This is a list of human anatomy mnemonics, categorized and alphabetized. For mnemonics in other medical specialties, see this list of medical mnemonics.
  • 16.9K
  • 24 Nov 2022
Topic Review
Power Electronic Switches
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less ‘forgotten’ power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch.
  • 16.8K
  • 29 Dec 2020
Topic Review
Fifth Generation Computer
The Fifth Generation Computer Systems (FGCS) was an initiative by Japan's Ministry of International Trade and Industry (MITI), begun in 1982, to create computers using massively parallel computing and logic programming. It was to be the result of a government/industry research project in Japan during the 1980s. It aimed to create an "epoch-making computer" with supercomputer-like performance and to provide a platform for future developments in artificial intelligence. There was also an unrelated Russian project also named as a fifth-generation computer (see Kronos (computer)). Ehud Shapiro, in his "Trip Report" paper (which focused the FGCS project on concurrent logic programming as the software foundation for the project), captured the rationale and motivations driving this project: The term "fifth generation" was intended to convey the system as being advanced. In the history of computing hardware, computers using vacuum tubes were called the first generation; transistors and diodes, the second; integrated circuits, the third; and those using microprocessors, the fourth. Whereas previous computer generations had focused on increasing the number of logic elements in a single CPU, the fifth generation, it was widely believed at the time, would instead turn to massive numbers of CPUs for added performance. The project was to create the computer over a ten-year period, after which it was considered ended and investment in a new "sixth generation" project would begin. Opinions about its outcome are divided: either it was a failure, or it was ahead of its time.
  • 16.8K
  • 21 Oct 2022
Topic Review
Injection
An injection (often and usually referred to as a "shot" in US English, a "jab" in UK English, or a "jag" in Scottish English and Scots) is the act of administering a liquid, especially a drug, into a person's body using a needle (usually a hypodermic needle) and a syringe. An injection is considered a form of parenteral drug administration; it does not involve absorption in the digestive tract. This allows the medication to be absorbed more rapidly and avoid the first pass effect. There are many types of injection, which are generally named after the body tissue the injection is administered into. This includes common injections such as subcutaneous, intramuscular, and intravenous injections, as well as less common injections such as intraperitoneal, intraosseous, intracardiac, intraarticular, and intracavernous injections. Injections are among the most common health care procedures, with at least 16 billion administered in developing and transitional countries each year. Of these, 95% are used in curative care or as treatment for a condition, 3% are to provide immunizations/vaccinations, and the rest are used for other purposes, including blood transfusions. The term injection is sometimes used synonymously with inoculation, but injection does not only refer to the act of inoculation. Injections generally administer a medication as a bolus (or one-time) dose, but can also be used for continuous drug administration. After injection, a medication may be designed to be released slowly, called a depot injection, which can produce long-lasting effects. An injection necessarily causes a small puncture wound to the body, and thus may cause localized pain or infection. The occurrence of these side effects varies based on injection location, the substance injected, needle gauge, procedure, and individual sensitivity. Rarely, more serious side effects including gangrene, sepsis, and nerve damage may occur. Fear of needles, also called needle phobia, is also common and may result in anxiety and fainting before, during, or after an injection. To prevent the localized pain that occurs with injections the injection site may be numbed or cooled before injection and the person receiving the injection may be distracted by a conversation or similar means. To reduce the risk of infection from injections, proper aseptic technique should be followed to clean the injection site before administration. If needles or syringes are reused between people, or if an accidental needlestick occurs, there is a risk of transmission of bloodborne diseases such as HIV and hepatitis. Unsafe injection practices contribute to the spread of bloodborne diseases, especially in less-developed countries. To combat this, safety syringes exist which contain features to prevent accidental needlestick injury and reuse of the syringe after it is used once. Furthermore, recreational drug users who use injections to administer the drugs commonly share or reuse needles after an injection. This has led to the development of needle exchange programs and safe injection sites as a public health measure, which may provide new, sterile syringes and needles to discourage the reuse of syringes and needles. Used needles should ideally be placed in a purpose-made sharps container which is safe and resistant to puncture. Some locations provide free disposal programs for such containers for their citizens.
  • 16.7K
  • 04 Nov 2022
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