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Topic Review
Sublevel Caving Production Scheduling
Production scheduling determines the most beneficial mining sequence over the life of mine. Developing a schedule that meets all mining aspects can substantially reduce mining costs and increase profitability. Among all underground mining methods, the sublevel caving (SLC) method is a common method with moderate development requirements, high production rate, and high degree of mechanization and flexibility. None of the manual planning methods and heuristic algorithms used in commercial software will lead to a truly optimal schedule. In sublevel caving, mathematical programming models, particularly mixed-integer programming, have been applied to provide an operationally feasible multi-time period's schedule. However, confined blasting conditions, chaotic material flow, and frequent mixing of ore and waste while loading broken ore at the drawpoint make sublevel caving method unique to produce a holistic plan.
  • 5.2K
  • 27 Aug 2021
Topic Review
Biodiesel from Castor Oil
An attractive alternative to the use of fossil fuels is biodiesel, which can be obtained from a variety of feedstock through different transesterification systems such as ultrasound, microwave, biological, chemical, among others. The efficient and cost-effective biodiesel production depends on several parameters such as free fatty acid content in the feedstock, transesterification reaction efficiency, alcohol: oil ratio, catalysts type, and several parameters during the production process. However, biodiesel production from vegetable oils is under development, causing the final price of biodiesel to be higher than diesel derived from petroleum. An alternative to decrease the production costs will be the use of economical feedstocks and simple production processes. Castor oil is an excellent raw material in terms of price and quality, but especially this non-edible vegetable oil does not have any issues or compromise food security. Recently, the use of castor oil has attracted attention for producing and optimizing biodiesel production, due to the high content of ricinoleic fatty acid and the possibility to esterify with only methanol, which assures low production costs. Additionally, biodiesel from castor oil has different advantages over conventional diesel. Some of them are biodegradable, non-toxic, renewable, they can be used alone, low greenhouse gas emission, among others. This review discusses and analyzes different transesterification processes, technologies, as well as different technical aspects during biodiesel production using castor oil as a feedstock.
  • 5.2K
  • 28 Oct 2020
Topic Review
Jaguar S-Type
The Jaguar S-Type was an executive car that debuted at the 1998 Birmingham Motor Show and was marketed by Jaguar for model years 1999-2008, reviving the nameplate of the company's 1963-68 S-Type as a four-door notchback saloon. The S-Type received a mild facelift for model year 2005. The 2002 S-Type 4.2 Supercharged V8 at the time, was the fastest road production saloon car in the world. The S-Type was discontinued in late 2007 and replaced by the XF.
  • 5.2K
  • 09 Nov 2022
Topic Review
Statistical Correlations of Criminal Behaviour
The statistical correlations of criminal behavior explore the associations of specific non-criminal factors with specific crimes. The field of criminology studies the dynamics of crime. Most of these studies use correlational data; that is, they attempt to identify various factors are associated with specific categories of criminal behavior. Such correlational studies led to hypotheses about the causes of these crimes. The Handbook of Crime Correlates (2009) is a systematic review of 5200 empirical studies on crime that have been published worldwide. A crime consistency score represents the strength of relationships. The scoring depends on how consistently a statistically significant relationship was identified across multiple studies. The authors claim that the review summarizes most of what is currently known about the variables associated with criminality. Writing in 2019, criminologist Greg Ridgeway argued that criminology was still trying to conclusively determine what causes crime.
  • 5.2K
  • 29 Nov 2022
Topic Review
Lysenkoism
Lysenkoism (Russian: Лысенковщина, romanized: Lysenkovshchina, [ɫɨˈsɛnkəfɕːʲɪnə], Ukrainian: лисенківщина, Template:IPA-uk) was a political campaign led by Trofim Lysenko against genetics and science-based agriculture in the mid-20th century, rejecting natural selection in favour of a form of Lamarckism, as well as expanding upon the techniques of vernalization and grafting. In time, the term has come to be identified as any deliberate distortion of scientific facts or theories for purposes that are deemed politically, religiously or socially desirable. More than 3,000 mainstream biologists were dismissed or imprisoned, and numerous scientists were executed in the campaign to suppress scientific opponents. The president of the Agriculture Academy, Nikolai Vavilov, who had been Lysenko's mentor, but later denounced him, was sent to prison and died there, while Soviet genetics research was effectively destroyed. Research and teaching in the fields of neurophysiology, cell biology, and many other biological disciplines were harmed or banned. Other countries of the Eastern Bloc including the People's Republic of Poland, the Republic of Czechoslovakia, and the German Democratic Republic accepted Lysenkoism as the official "new biology", to varying degrees, as did the People's Republic of China for some years. The government of the USSR supported the campaign, and Joseph Stalin personally edited a speech by Lysenko in a way that reflected his support for what would come to be known as Lysenkoism, despite his skepticism toward Lysenko's assertion that all science is class-oriented in nature. Lysenko served as the director of the Soviet Union's Lenin All-Union Academy of Agricultural Sciences.
  • 5.2K
  • 02 Nov 2022
Topic Review
Tuskegee Syphilis Experiment
The Tuskegee Study of Untreated Syphilis in the African American Male was a clinical study conducted between 1932 and 1972 by the United States Public Health Service. The purpose of this study was to observe the natural history of untreated syphilis; the African-American men in the study were only told they were receiving free health care from the Federal government of the United States. The Public Health Service started the study in 1932 in collaboration with Tuskegee University (then the Tuskegee Institute), a historically black college in Alabama. Investigators enrolled in the study a total of 600 impoverished, African-American sharecroppers from Macon County, Alabama. Of these men, 399 had latent syphilis, with a control group of 201 men who were not infected. As an incentive for participation in the study, the men were promised free medical care, but were deceived by the PHS, who disguised placebos, ineffective methods, and diagnostic procedures as treatment. The men who had syphilis were never informed of their diagnosis, despite the risk of infecting others, and the fact that the disease could lead to blindness, deafness, mental illness, heart disease, bone deterioration, collapse of the central nervous system, and death.. According to the Centers for Disease Control and Prevention, the men were told that they were being treated for "bad blood,” a colloquialism that described various conditions such as syphilis, anemia and fatigue. "Bad blood"—specifically the collection of illnesses the term included—was a leading cause of death within the southern African-American community. The men were initially told that the study was only going to last six months, but it was extended to 40 years. After funding for treatment was lost, the study was continued without informing the men that they would never be treated. None of the infected men were treated with penicillin despite the fact that by 1947, the antibiotic had become the standard treatment for syphilis. Study clinicians could have chosen to treat all syphilitic subjects and close the study, or split off a control group for testing with penicillin. Instead, they continued the study without treating any participants; they withheld treatment and information about it from the subjects. In addition, scientists prevented participants from accessing syphilis treatment programs available to other residents in the area. The study continued, under numerous Public Health Service supervisors, until 1972, when a leak to the press resulted in its termination on November 16 of that year. The victims of the study, all African-American, included numerous men who died of syphilis, 40 wives who contracted the disease and 19 children born with congenital syphilis. The 40-year Tuskegee Study of Untreated Syphilis in the African American Male study was a major violation of ethical standards. Researchers knowingly failed to treat participants appropriately after penicillin was proven to be an effective treatment for syphilis and became widely available. Moreover, participants remained ignorant of the study clinicians’ true purpose, which was to observe the natural course of untreated syphilis. The revelation in 1972 of study failures by a whistleblower, Peter Buxtun, led to major changes in U.S. law and regulation concerning the protection of participants in clinical studies. Now studies require informed consent, communication of diagnosis and accurate reporting of test results. The Tuskegee Syphilis Study, cited as "arguably the most infamous biomedical research study in U.S. history," led to the 1979 Belmont Report and to the establishment of the Office for Human Research Protections (OHRP). It also led to federal laws and regulations requiring institutional review boards for the protection of human subjects in studies involving them. The OHRP manages this responsibility within the United States Department of Health and Human Services (HHS). On May 16, 1997, President Bill Clinton formally apologized on behalf of the United States to victims of the study.
  • 5.2K
  • 07 Nov 2022
Topic Review
Toxicological Risks of the Cobalt–Chromium Alloys in Dentistry
Cobalt–chromium (Co-Cr) alloys have been used for a long period of time in dentistry, but several risk factors remain involved. The toxicological risk of Co-Cr dental alloys is actually a sensitive subject with the European regulatory changes, namely regulation (EU) 2017/745 and annex VI to the CLP regulation (EC) 1972/2008. Studies assessing Co-Cr dental alloys’ biocompatibility are urgently needed.
  • 5.2K
  • 22 Feb 2023
Topic Review
Secularity
Secularity (from Latin saeculum, "worldly" or "of a generation") is the state of being separate from religion, or of not being exclusively allied with or against any particular religion. Historically, the word secular was not related or linked to religion, but was a freestanding term in Latin which would relate to any mundane endeavour. However, the term, saecula saeculorum (saeculōrum being the genitive plural of saeculum) as found in the New Testament in the Vulgate translation (circa 410) of the original Koine Greek phrase εἰς τοὺς αἰῶνας τῶν αἰώνων (eis toùs aionas ton aiṓnōn), e.g. at Galatians 1:5, was used in the early Christian church (and is still used today), in the doxologies, to denote the coming and going of the ages, the grant of eternal life, and the long duration of created things from their beginning to forever and ever. The idea of a dichotomy between religion and the secular originated in the European Enlightenment. Furthermore, since religion and secular are both Western concepts that were formed under the influence of Christian theology, other cultures do not necessarily have words or concepts that resemble or are equivalent to them. In many cultures, "little conceptual or practical distinction is made between 'natural' and 'supernatural' phenomena" and the very notions of religious and nonreligious dissolve into unimportance, nonexistence, or unawareness, especially since people have beliefs in other supernatural or spiritual things irrespective of belief in God or gods. Conceptions of what is and what is not religion vary in contemporary East Asia as well. The shared term for "irreligion" or "no religion" (無宗教, Chinese pron. wú zōngjiào, Japanese pron. mu shūkyō) with which the majority of East Asian populations identify themselves implies non-membership in one of the institutional religions (such as Buddhism and Christianity) but not necessarily non-belief in traditional folk religions collectively represented by Chinese Shendao (shén dào) and Japanese Shinto (both meaning "ways of gods").[lower-alpha 1] In modern Japan, religion has negative connotation since it is associated with foreign belief systems so many identify as "nonreligious" (mushukyo), but this does not mean they have a complete rejection or absence of beliefs and rituals relating to supernatural, metaphysical, or spiritual things. In the Meiji era, the Japanese government consciously excluded Shinto from the category of religion in order to enforce State Shinto while asserting their state followed American-mandated requirements for freedom of religion; this has fed into the contemporary Japanese experience of "secularity" as well as the government's regulation of religious beliefs and institutions from the Meiji era into the present day. One can regard eating and bathing as examples of secular activities, because there may not be anything inherently religious about them. Nevertheless, some religious traditions see both eating and bathing as sacraments, therefore making them religious activities within those world views. Saying a prayer derived from religious text or doctrine, worshipping through the context of a religion, performing corporal and spiritual works of mercy, and attending a religious seminary school or monastery are examples of religious (non-secular) activities. The "secular" is experienced in diverse ways ranging from separation of religion and state to being anti-religion or even pro-religion, depending on the culture. For example, the United States has both separation of church and state and pro-religiosity in various forms such as protection of religious freedoms; France has separation of church and state (and French Revolution was strongly anti-religious); the Soviet Union was anti-religion; in India, people feel comfortable identifying as secular while participating in religion; and in Japan, since the concept of "religion" is not indigenous to Japan, people state they have no religion while doing what appears to be religion to Western eyes. A related term, secularism, involves the principle that government institutions and their representatives should remain separate from religious institutions, their beliefs, and their dignitaries. Many businesses and corporations, and some governments operate on secular lines. This stands in contrast to theocracy, government with deity as its highest authority.
  • 5.2K
  • 27 Oct 2022
Topic Review
Family in Medieval Society
One of the periods with the greatest social, cultural, and religious changes was, without a doubt, the European medieval period. The concept of “Family” was one of the fields that gradually evolved, from individuals who shared the same biological lineage, to members of the same “House”. One of the ways to study the concept of “Family” in ancient periods is through a bioarchaeological perspective, where both anthropology and genetics have proven to be essential disciplines for studying “Families”. Through burial rituals, observing whether the graves were single or multiple, as is carried out in the study of human remains, it discusses the profound contribution of anthropology to the “Family” investigation, through mobility studies, the investigation of biological sex, observing certain congenital anomalies or, even, the study of certain ancient infectious diseases. Concerning genetics, the study of bones or teeth allows us to determine whether individuals were from the same close family or if they belonged to the same lineage through the maternal and paternal sides, being one of the only scientific ways of proposing social relationships between individuals, such as that created through adoption.
  • 5.2K
  • 28 Feb 2024
Topic Review
Sustainability and Sharing Economy
The sharing economy is usually related to sustainability, and it is framed as: (a) an economic opportunity, (b) a more sustainable form of consumption and (c) a pathway to an equitable and sustainable economy. 
  • 5.2K
  • 30 Oct 2024
Topic Review
Diffused Religion Beyond Secularization
Diffused religion theory concerns the capacity of a dominant religion in a country to remain solid for centuries.
  • 5.2K
  • 01 Nov 2020
Topic Review
Health Effects of 8-Prenylnaringenin
8-Prenylnaringenin is a natural compound biosynthesised in the lupulin glands of the hop inflorescences. It is the substance with the highest estrogenic activity known so far in the plant kingdom. As estrogens have many targets in animals and humans, the health effects of 8-prenylnaringenin can be either beneficial or adverse depending on the physiological status of the consumers.
  • 5.2K
  • 08 Feb 2023
Topic Review
Charlotte's Web (Cannabis)
Charlotte's Web is a high-cannabidiol (CBD), low-tetrahydrocannabinol (THC) Cannabis strain marketed as a dietary supplement under federal law of the United States. It is produced by the Stanley brothers in Colorado. It does not induce the psychoactive "high" typically associated with recreational marijuana strains that are high in THC. In September 2014, the Stanleys announced that they would ensure that the product consistently contained less than 0.3% THC. Charlotte's Web is named after Charlotte Figi, born (2006-10-18) October 18, 2006 (age 16), whose story has led to her being described as "the girl who is changing medical marijuana laws across America." Her parents and physicians say she experienced a reduction of her epileptic seizures brought on by Dravet syndrome after her first dose of medical marijuana at five years of age. Her usage of Charlotte's Web was first featured in the 2013 CNN documentary "Weed". Media coverage increased demand for Charlotte's Web and similar products high in CBD, which has been used to treat epilepsy in toddlers and children. It was originally called "Hippie's Disappointment" as it was a strain that had high CBD and could not induce a "high". While anecdotal reports have sparked interest in treatment with cannabinoids, there is not enough evidence to draw conclusions with certainty about their safety or efficacy. Physicians worry that some parents are willing to try treatments before proper research has been conducted, and that they may be disappointed. They are "alarmed by parallels to past miracle-cure manias later proved false..." and "...wary of the heightened placebo effect in treatments involving children, when reports of progress depend on the view of parents."
  • 5.2K
  • 02 Nov 2022
Topic Review
Faster-Than-Light Communication
Superluminal communication is a hypothetical process in which information is sent at faster-than-light (FTL) speeds. The current scientific consensus is that faster-than-light communication is not possible, and to date it has not been achieved in any experiment. Under present knowledge superluminal communication is impossible because, in a Lorentz-invariant theory, it could be used to transmit information into the past. This contradicts causality and leads to logical paradoxes. A number of theories and phenomena related to superluminal communication have been proposed or studied, including tachyons, quantum nonlocality, and wormholes.
  • 5.2K
  • 19 Oct 2022
Topic Review
Chi square statistic
The Chi-Square test is based on a series of assumptions frequently used in the statistical analysis of experimental data. The main weakness of the chi-square test is that is very accurate only in convergence (in large size samples), and for small sample sizes is exposed to errors of both types (type I and type II). On two scenarios of use - goodness of fit and contingencies assessment (2x2 tables of contingency) - here are discussed different aspects involving it. Further knowledge on the regard of the type of the error in contingencies assessment push further the analysis of the data, while in the same time opens the opportunity to devise a method for filling the gaps in contingencies (e.g. censored data), both scenarios being discussed here in detail. A program designed to fill the gaps in the assumption of the association is provided.
  • 5.2K
  • 24 Dec 2020
Topic Review
Purification of Biodiesel Glycerol from Waste Oils
To facilitate the glycerol purification, it is important to know the composition of glycerol from the biodiesel obtained from waste oils and how these oils and the type of biodiesel synthesis influence the glycerol composition. First, different glycerol impurities were studied based on the oil origin and the used catalysts. Thus, the glycerol impurities are detailed to show their influence on the glycerol or on its transformation in other products. Different glycerol characterization techniques were used to determine the purity level and properties of glycerol. The main interest of this part is to describe different methods to purify glycerol and to understand its composition and its utilization.
  • 5.2K
  • 20 May 2022
Topic Review
Identity
Identity refers to the distinct and unique set of characteristics, qualities, beliefs, and affiliations that define an individual or a group. It encompasses various aspects, including personal attributes, cultural heritage, social roles, and a sense of belonging. Identity is dynamic, shaped by personal experiences, societal influences, and the interactions between individuals and their broader cultural, social, and historical contexts. It plays a crucial role in shaping how individuals perceive themselves and how they are perceived by others. Additionally, identity can be expressed through factors such as ethnicity, nationality, gender, religion, and personal values, contributing to the richness and diversity of human experiences.
  • 5.2K
  • 25 Jan 2024
Topic Review
Western European Colonialism and Colonization
File:SierraLeoneHofstra3.1.tiff European colonialism and colonization was the policy or practice of acquiring full or partial political control over other societies and territories, creating a colony, occupying it with settlers, and exploiting it economically. Research suggests, the current conditions of postcolonial countries have roots in colonial actions and policies. For example, colonial policies, such as the type of rule implemented, the nature of investments, and identity of the colonizers, are cited as impacting postcolonial states. Examination of the state-building process, economic development, and cultural norms and mores shows the direct and indirect consequences of colonialism on the postcolonial states.
  • 5.2K
  • 04 Nov 2022
Topic Review
Fault-Tolerant Control
Fault-tolerant controllers (FTCs) can be defined as controllers that are able to tolerate faults and keep the control performance in the ideal range in the presence of faults. FTC approaches can be categorized into two main categories: Passive FTCs and Active FTC. Passive FTCs are not dependent on fault detection and isolation (FDI) modules and can keep the desired controller performance without considering the type and size of fault. Active FTCs are equipped with the FDI module and behave differently to different kinds of fault.
  • 5.2K
  • 27 Oct 2020
Topic Review
Textile Production
The textile production is constantly increasing by offering products to fashion, style and marketing needs, or even to progressively competitive technical challenges. The perspective of innovation and development is in contrast with the highly polluting impact on the surroundings of this industrial activity.
  • 5.2K
  • 09 Feb 2021
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