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Topic Review
Law of Social Cycle
The law of social cycle is a social cycle theory developed by Prabhat Ranjan Sarkar. It is based on the theory of human historical motivity based on "the ancient spiritual ideas of the Vedas". The theory was developed in the 1950s and expanded by Ravi Batra since the 1970s, Johan Galtung and Sohail Inayatullah since the 1990s and others.
  • 2.6K
  • 14 Nov 2022
Topic Review
History and Implementations of ZFS
The history and implementations of ZFS covers the development of the ZFS file system. ZFS began as part of the Sun Microsystems Solaris operating system in 2001. Large parts of Solaris - including ZFS - were published under an open source license as OpenSolaris for around 5 years from 2005, before being placed under a closed source license when Oracle Corporation acquired Sun in 2009/2010. During 2005 - 2010, the open source version of ZFS was ported to Linux, Mac OS X (continued as MacZFS) and FreeBSD. In 2010, the illumos project forked a recent version of OpenSolaris, to continue its development as an open source project, including ZFS. In 2013 the co-ordination of open source ZFS moved to an umbrella organization, OpenZFS, which allowed any person or organization that wished to use the open source version of ZFS, to collaborate in developing and maintaining a single common version of ZFS. illumos remains very closely involved with OpenZFS. As of 2018, there are two main implementations of ZFS, both quite similar: Oracle's implementation, which is closed source and part of Solaris, and OpenZFS, which is widely used to provide ZFS on many unix-like operating systems.
  • 2.6K
  • 23 Nov 2022
Topic Review
Wind Energy Conversion Systems Based on Synchronous Generator
Since 20th century, electricity has been widely available, and a large portion of it is produced using coal and gas. Because of its adaptability and simplicity of delivery, electricity is a premium kind of energy. Global demand is rising because of rising consumer electronics, associated industrial activities, and greater consumer access in emerging nations. The most reliable and progressive renewable energy source is wind power. Utilizing the highest amount of wind power available and operating the wind turbine (WT) at its maximum energy conversion output is essential for the rapid adoption of wind generators in electrical grids. To complete this, a wind energy conversion system (WECS) must track or run at the maximum power point.
  • 2.6K
  • 23 Mar 2023
Topic Review
Love Letter
A love letter is a romantic way to express feelings of love in written form. Whether delivered by hand, mail, carrier pigeon, or romantically left in a secret location, the letter may be anything from a short and simple message of love to a lengthy explanation of feelings. Love letters may 'move through the widest range of emotions – devotion, disappointment, grief and indignation, self-confidence, ambition, impatience, self-reproach and resignation'.
  • 2.6K
  • 17 Nov 2022
Topic Review
Cultural Values in Water Management and Governance
Water is a fundamental resource for ecological and economic imperatives across the globe, contributing to the sustenance of livelihoods, food production and energy generation. Despite its importance, water resources are increasingly under threat due to overexploitation, pollution, scarcity, depletion and issues of accessibility/affordability. In addition to these threats, competitive water uses and strong interdependencies across different productive sectors. As such, “water crises” have been repeatedly identified among the top five global risks since 2012, with the international community acknowledging that water crises are regularly a crisis of management and/or governance. Cultural values associated with water management revolve around anthropocentrism, whereas values associated with water governance revolve around concepts of provenance/places. Implementation of ToC/cultural values is limited in practical applications, and an example is provided on how to improve on that. It's suggested that a succinct theory of culture such as Schwartz’s cultural values be considered to be an alternative to capture a greater heterogeneity across the breadth of water governance/management-related and basin-specific contexts. 
  • 2.6K
  • 18 Mar 2022
Biography
George Robert Carruthers
George Robert Carruthers (born October 1, 1939) is an award-winning African-American inventor, physicist, and space scientist. Carruthers invented the ultraviolet camera/spectograph for NASA to use when it launched Apollo 16 in 1972. His work also demonstrated that molecular hydrogen exists in the interstellar medium. In 2003, Carruthers was inducted into the National Inventor's Hall of Fame. He
  • 2.6K
  • 15 Nov 2022
Topic Review
List of Vulnerable Plants
As of September 2016, the International Union for Conservation of Nature (IUCN) lists 5430 vulnerable plant species. 25% of all evaluated plant species are listed as vulnerable. The IUCN also lists 244 subspecies and 235 varieties as vulnerable. No subpopulations of plants have been evaluated by the IUCN. For a species to be assessed as vulnerable to extinction the best available evidence must meet quantitative criteria set by the IUCN designed to reflect "a high risk of extinction in the wild". Endangered and critically endangered species also meet the quantitative criteria of vulnerable species, and are listed separately. See: List of endangered plants, List of critically endangered plants. Vulnerable, endangered and critically endangered species are collectively referred to as threatened species by the IUCN. Additionally 1674 plant species (7.6% of those evaluated) are listed as data deficient, meaning there is insufficient information for a full assessment of conservation status. As these species typically have small distributions and/or populations, they are intrinsically likely to be threatened, according to the IUCN. While the category of data deficient indicates that no assessment of extinction risk has been made for the taxa, the IUCN notes that it may be appropriate to give them "the same degree of attention as threatened taxa, at least until their status can be assessed." This is a complete list of vulnerable plant species, subspecies and varieties evaluated by the IUCN.
  • 2.6K
  • 05 Dec 2022
Topic Review
Cell Finishing Process Chain
The cell finishing process is the final stage in the production of a battery cell. Almost one third of the production costs of a battery cell are related to this part of the production. It includes a series of steps and technologies aimed at optimizing the battery cell’s performance, quality, and safety. The process is divided into three categories: pre-treatment, formation procedure, and quality testing. The order of the processes and the time required for each step can vary depending on the manufacturer and the cell format.
  • 2.6K
  • 14 Apr 2023
Topic Review
pH Responsive Polyurethane for Biomedical and Drug Delivery
pH-responsive polymers are polymers that respond to changes in environmental pH. They can be classified into: (A) polymers with ionizable moieties; and (B) polymers that contain acid-labile linkages. pH-responsive polyurethanes demonstrated good biological response and sustainability in biomedical applications and drug delivery. They have been used as controlled drug delivery systems for oral administration, intravaginal administration, and targeted drug delivery systems for chemotherapy treatment. 
  • 2.6K
  • 12 May 2022
Topic Review
Artificial Uterus
An artificial uterus (or artificial womb) is a hypothetical device that would allow for external pregnancy by growing a fetus outside the body of an organism that would normally carry the fetus to term. An artificial uterus, as a replacement organ, would have many applications. It could be used to assist male or female couples in the development of a fetus. This can potentially be performed as a switch from a natural uterus to an artificial uterus, thereby moving the threshold of fetal viability to a much earlier stage of pregnancy. In this sense, it can be regarded as a neonatal incubator with very extended functions. It could also be used the for initiation of fetal development. An artificial uterus could also help make fetal surgery procedures at an early stage an option instead of having to postpone them until term of pregnancy. In 2016 scientists published two studies regarding human embryos developing for thirteen days within an ecto-uterine environment. Currently, a 14-day rule prevents human embryos from being kept in artificial wombs longer than 14 days. This rule has been codified into law in twelve countries. In 2017 fetal researchers at the Children's Hospital of Philadelphia published a study showing they had grown premature lamb fetuses for four weeks in an extra-uterine life support system.
  • 2.6K
  • 27 Sep 2022
Topic Review
Years of Living Dangerously
Years of Living Dangerously is an American documentary television series focusing on global warming. The first season was broadcast in the US in 2014 on Showtime. It won an Emmy Award as Outstanding Documentary or Nonfiction Series. The second season aired on the National Geographic Channel in 2016. Executive producers included James Cameron, Arnold Schwarzenegger, and series creators Joel Bach and David Gelber (formerly of 60 Minutes). Joseph Romm and Heidi Cullen were the chief science advisors. The weekly episodes featured celebrity hosts with a history of environmental activism and well-known journalists with a background in environmental reportage. These "correspondents" traveled the world and throughout the U.S. to interview experts and ordinary people affected by, and seeking solutions to, the effects of global warming. They acted as reporters and proxies for the audience, asking questions to find out people's opinions and to discover the scientific evidence. The final episode of season one featured an interview of President Barack Obama. Episodes explored the effects of rising sea levels, historic droughts and flooding, water scarcity, ocean acidification, deforestation and the rapidly increasing extinction rate of species, but also focused on "solutions that individuals, communities, companies and even governments can use to address worldwide climate change", including cheaper solar and wind energy, advancing battery technology and electric cars. Hosts included Cameron, Schwarzenegger, Harrison Ford, Ian Somerhalder, America Ferrera, David Letterman, Gisele Bündchen, Jack Black, Matt Damon, Jessica Alba, Sigourney Weaver, and various other actors and journalists. Schwarzenegger reflected on how the series tries to make the issue of climate change resonate with the public: "I think the environmental movement only can be successful if we are simple and clear and make it a human story. We will tell human stories in this project. The scientists would never get the kind of attention that someone in show business gets." Cameron elaborated: "We didn’t use our celebrities as talking head experts, because they’re not climate experts. They were concerned, intelligent, curious citizens who were out to find answers. They were functioning as journalists." Newsweek said that the celebrity hosts "lend sparks to an issue that sends most viewers for the exits".
  • 2.6K
  • 01 Nov 2022
Topic Review
Bt Brinjal
The Bt brinjal is a suite of transgenic brinjals (also known as an eggplant or aubergine) created by inserting a crystal protein gene (Cry1Ac) from the soil bacterium Bacillus thuringiensis into the genome of various brinjal cultivars. The insertion of the gene, along with other genetic elements such as promoters, terminators and an antibiotic resistance marker gene into the brinjal plant is accomplished using Agrobacterium-mediated genetic transformation. The Bt brinjal has been developed to give resistance against lepidopteron insects, in particular the Brinjal Fruit and Shoot Borer (Leucinodes orbonalis)(FSB). Mahyco, an Indian seed company based in Jalna, Maharashtra, has developed the Bt brinjal. The genetically modified brinjal event is termed Event EE 1, and Mahyco have also applied for approval of two brinjal hybrids. The Event EE 1 was introgressed by plant breeding into various local varieties by University of Agricultural Sciences, Dharwad and Tamil Nadu Agricultural University, Coimbatore. Some of the cultivars of brinjal include: Malpur local, Manjari gota, Kudachi local, Udupi local, 112 GO, and Pabkavi local. It was approved for commercialization in India in 2009, but - after an apparent public outcry and rounds of debates in which representatives from Mahyco, the scientific community, and NGO's spoke on the topic - the then Indian Environment Minister, Jairam Ramesh, facilitated a moratorium on its release until further, unspecified, tests were conducted. Bt brinjal was approved for commercial release in Bangladesh in 2013.
  • 2.6K
  • 28 Nov 2022
Topic Review
Paper-Based Sensors Application
Paper-based sensors are getting increasing attention for reliable indoor/outdoor onsite detection with non-expert operation due to low cost, portability, easy disposal, and high accuracy, as well as bulky reduced laboratory equipment. They have become powerful analysis tools in trace detection with ultra-low detection limits and extremely high accuracy, resulting in their great popularity in biological detection, environmental inspection, and other applications. However, the current paper-based sensors still encounter insufficiencies such as harsh storage, short shelf time, singleplex analyte detection, disability of holographic strain detection, and low reproducibility for direct detection of the actual sample without pretreatment. Efforts should be made to paper-based sensors with those concerns before their broad commercial application. 
  • 2.6K
  • 22 Sep 2021
Topic Review
Performance Paradox
The performance paradox is a theory set forth by Marshall W. Meyer and Vipin Gupta in 1994, which posits that organizations are able to maintain control by not knowing what exactly performance is. This theory is based on several facts of performance, namely that the number and type of performance measurements that exist are increasing at a rapid rate and that these new metrics tend to be weakly correlated with old ones.
  • 2.6K
  • 20 Oct 2022
Topic Review
Animal Foods' Lactic Acid Bacteria
A variety of lactic acid bacteria (LAB) strains, which are either part of the autochthonous microbiota or introduced into animal products, have potential beneficial applications for the preservation of such products and/or for consumer health. Many foods obtained from fermented products of animal origin, such as meat, fish, and dairy, contain living microorganisms that are phylogenetically similar to probiotic LAB as part of the microbiota that directs their fermentation process and is responsible for their unique character. Fermented foods, such as cultured milk, yogurt, cheese, fermented sausage, and certain types of wine, are obtained through enzymatic reactions resulting from controlled microbial growth, in which the main microbial effectors comprise, primarily, LAB and their metabolites.
  • 2.6K
  • 17 Jan 2022
Topic Review
Scarr-Rowe Effect
In behavioral genetics, the Scarr-Rowe effect, also known as the Scarr-Rowe hypothesis, refers to the proposed moderating effect of low socioeconomic status on the heritability of children's IQ. According to this hypothesis, lower socioeconomic status and greater exposure to social disadvantage during childhood leads to a decrease in the heritability of IQ, as compared to children raised in more advantaged environments. It is considered an example of gene–environment interaction. This hypothesized effect was first proposed by Sandra Scarr, who found support for it in a 1971 study of twins in Philadelphia, and these results were replicated by David C. Rowe in 1999. A 2015 meta-analysis found the effect was predominant in the United States while less evident in societies with robust child welfare systems.
  • 2.6K
  • 10 Nov 2022
Topic Review
Cryptomeria japonica
Cryptomeria japonica, a commercially important tree throughout Asia and the Azores Archipelago (Portugal), is currently waste/by-products of wood processing that can be converted into eco-friendly and high added-value products, such as essential oils (EOs), with social, environmental and economic impacts.
  • 2.6K
  • 07 Dec 2021
Topic Review
BCR-ABL1 Tyrosine Kinase Complex Signaling Transduction
The constitutively active BCR-ABL1 tyrosine kinase, found in t(9;22)(q34;q11) chromosomal translocation-derived leukemia, initiates an extremely complex signaling transduction cascade that induces a strong state of resistance to chemotherapy. Targeted therapies based on tyrosine kinase inhibitors (TKIs), such as imatinib, dasatinib, nilotinib, bosutinib, and ponatinib, have revolutionized the treatment of BCR-ABL1-driven leukemia, particularly chronic myeloid leukemia (CML). However, TKIs do not cure CML patients, as some develop TKI resistance and the majority relapse upon withdrawal from treatment. Importantly, although BCR-ABL1 tyrosine kinase is necessary to initiate and establish the malignant phenotype of Ph-related leukemia, in the later advanced phase of the disease, BCR-ABL1-independent mechanisms are also in place. 
  • 2.6K
  • 09 Feb 2022
Topic Review
Heritage Tourism in Mexico
Tourism activity in general, with the heritage tourism sector in particular, represented the second inflow of foreign currency to Mexico in 2019 (pre-pandemic), with more than USD 24 million. According to local polls, the main purpose of travel is leisure. However, more than half of tourists (local and foreigner) who visit Mexico enjoy/visit an archaeological site, a museum, and/or a local community.
  • 2.6K
  • 01 Apr 2022
Topic Review
Uranium Mineralization of Fossil Wood
Sandstone-hosted uranium deposits commonly contain abundant organic matter, including fossil logs. The precipitation of uranium minerals is often related to reducing environments associated with these organic materials. Below the water table, uranium is likely to be precipitated as uraninite (UO2), but in drier zones a variety of uranium minerals may be found. These minerals may occur as replacements for cellular tissue, or as surface crusts or fracture fillings.
  • 2.6K
  • 28 Oct 2020
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