Search | Encyclopedia MDPI

Your browser does not fully support modern features. Please upgrade for a smoother experience.

Subject:

Sort by:

Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)

Filter:

All Topic Review Biography Peer Reviewed Entry Video Entry

Topic Review

In orbital mechanics (subfield of celestial mechanics), Gauss's method is used for preliminary orbit determination from at least three observations (more observations increases the accuracy of the determined orbit) of the orbiting body of interest at three different times. The required information are the times of observations, the position vectors of the observation points (in Equatorial Coordinate System), the direction cosine vector of the orbiting body from the observation points (from Topocentric Equatorial Coordinate System) and general physical data. Carl Friedrich Gauss developed important mathematical techniques (summed up in Gauss's methods) which were specifically used to determine the orbit of Ceres. The method shown following is the orbit determination of an orbiting body about the focal body where the observations were taken from, whereas the method for determining Ceres' orbit requires a bit more effort because the observations were taken from Earth while Ceres orbits the Sun.

3.5K
10 Nov 2022

Topic Review

Sesame (Sesamum indicum L.) is an important oilseed crop with well-developed value chains. It is Ethiopia’s most valuable export commodity after coffee (Coffea arabica L.), contributing to socioeconomic development. The productivity of the crop is low and stagnant in Ethiopia and other major sesame growing regions in sub-Saharan Africa (<0.6 t/ha) due to a multitude of production constraints. The low yield of sesame is attributable to a lack of high-yielding and well-adapted varieties, susceptibility to capsule shattering, the prevalence of biotic and abiotic stresses, and a lack of modern production technologies such as optimal agronomic managing practices, row planters, harvesters, and storage facilities.

3.5K
17 Jan 2022

Topic Review

Biofilm and Pathogen Inhibition in Cooling Towers Using Natural Chemistry

Industrial comfort cooling and process cooling typically employ water evaporative cooling towers (CTs) to dissipate reject heat. This warm water, enriched with nutrient materials scrubbed from the air or in source water, provides a nurturing environment for a wide variety of neutrophilic microorganisms, some of which are human pathogens. For example, cases of Legionella pneumophila infection have been traced to CT Systems that have become pubic hazards in recent years. Typically, one or more toxic microbicides are applied to control the problem. This article highlights two case studies that utilize ultra-softened (<0.3 mg/L total hardness), highly-concentrated chemical components, naturally present in almost all makeup water sources used by CT Systems, that can generate high-pH, high-TDS cooling water. At sufficient concentrations, these two natural parameters are hostile to microorganisms, including protozoa and slime-forming (biofilm) bacteria that harbor pathogens. Field testing for Adenosine Tri-Phosphate (ATP), reported in Relative Light Units (RLU), provides a quick, sensitive method to detect all water-borne microbiological activity present in CT Systems and verifies the effectiveness of the anti-microbial program by quantifiable data, reported as ATP-RLU.

3.5K
28 Oct 2020

Topic Review

Wild Animal Suffering

Wild animal suffering is the suffering experienced by nonhuman animals living outside of direct human control, due to harms such as disease, injury, parasitism, starvation and malnutrition, dehydration, weather conditions, natural disasters, and killings by other animals, as well as psychological stress. Some estimates indicate that the vast majority of individual animals in existence live in the wild. A vast amount of natural suffering has been described as an unavoidable consequence of Darwinian evolution and the pervasiveness of reproductive strategies which favor producing large numbers of offspring, with a low amount of parental care and of which only a small number survive to adulthood, the rest dying in painful ways, has led some to argue that suffering dominates happiness in nature. The topic has historically been discussed in the context of the philosophy of religion as an instance of the problem of evil. More recently, starting in the 19th-century, a number of writers have considered the suspected scope of the problem from a secular standpoint as a general moral issue, one that humans might be able to take actions toward preventing. There is considerable disagreement around this latter point as many believe that human interventions in nature, for this reason, should not take place because of practicality, valuing ecological preservation over the well-being and interests of individual animals, considering any obligation to reduce wild animal suffering implied by animal rights to be absurd, or viewing nature as an idyllic place where happiness is widespread. Some have argued that such interventions would be an example of human hubris, or playing God and use examples of how human interventions, for other reasons, have unintentionally caused harm. Others, including animal rights writers, have defended variants of a laissez-faire position, which argues that humans should not harm wild animals, but that humans should not intervene to reduce natural harms that they experience. Advocates of such interventions argue that animal rights and welfare positions imply an obligation to help animals suffering in the wild due to natural processes. Some have asserted that refusing to help animals in situations where humans would consider it wrong not to help humans is an example of speciesism. Others argue that humans intervene in nature constantly—sometimes in very substantial ways—for their own interests and to further environmentalist goals. Human responsibility for enhancing existing natural harms has also been cited as a reason for intervention. Some advocates argue that humans already successfully help animals in the wild, such as vaccinating and healing injured and sick animals, rescuing animals in fires and other natural disasters, feeding hungry animals, providing thirsty animals with water, and caring for orphaned animals. nThey also assert that although wide-scale interventions may not be possible with our current level of understanding, they could become feasible in the future with improved knowledge and technologies. For these reasons, they claim it is important to raise awareness about the issue of wild animal suffering, spread the idea that humans should help animals suffering in these situations and encourage research into effective measures which can be taken in the future to reduce the suffering of these individuals, without causing greater harms.

3.5K
29 Sep 2022

Topic Review

Machine Learning for Plant Breeding/Biotechnology

Classical univariate and multivariate statistics are the most common methods used for data analysis in plant breeding and biotechnology studies. Evaluation of genetic diversity, classification of plant genotypes, analysis of yield components, yield stability analysis, assessment of biotic and abiotic stresses, prediction of parental combinations in hybrid breeding programs, and analysis of in vitro-based biotechnological experiments are mainly performed by classical statistical methods. Despite successful applications, these classical statistical methods have low efficiency in analyzing data obtained from plant studies, as the genotype, environment, and their interaction (G × E) result in nondeterministic and nonlinear nature of plant characteristics. Large-scale data flow, including phenomics, metabolomics, genomics, and big data, must be analyzed for efficient interpretation of results affected by G × E. Nonlinear nonparametric machine learning techniques are more efficient than classical statistical models in handling large amounts of complex and nondeterministic information with "multiple-independent variables versus multiple-dependent variables" nature. Neural networks, partial least square regression, random forest, and support vector machines are some of the most fascinating machine learning models that have been widely applied to analyze nonlinear and complex data in both classical plant breeding and in vitro-based biotechnological studies. High interpretive power of machine learning algorithms has made them popular in the analysis of plant complex multifactorial characteristics. The classification of different plant genotypes with morphological and molecular markers, modeling and predicting important quantitative characteristics of plants, the interpretation of complex and nonlinear relationships of plant characteristics, and predicting and optimizing of in vitro breeding methods are the examples of applications of machine learning in conventional plant breeding and in vitro-based biotechnological studies. Precision agriculture is possible through accurate measurement of plant characteristics using imaging techniques and then efficient analysis of reliable extracted data using machine learning algorithms. Perfect interpretation of high-throughput phenotyping data is applicable through coupled machine learning-image processing. This entry shows how nonlinear machine learning algorithms can be used in different branches of classical plant breeding and in vitro-based methods. An idea is provided at the end of the entry that shows how coupled image processing-machine learning (especially deep CNN) could be used to identify the ploidy level of plants. It could be used in laboratories without flowcytometry equipment and/or in plant species without an established chromosome counting protocol.

3.5K
17 Feb 2021

Topic Review

Addiction Psychology

Professionals view addiction as a disease or a choice. One model is referred to as the disease model of addiction. The second model is the choice model of addiction. Researchers argue that the addiction process is like the disease model with a target organ being the brain, some type of defect, and symptoms of the disease. Addiction is like the choice model with a disorder of genes, a reward, memory, stress, and choice. Both models result in compulsive behavior. Substance addictions relate to drugs, alcohol, and smoking. Process addictions relate to non-substance-related behaviors such as gambling, spending, sexual activity, gaming, the internet, and food. Psychologists' oldest definition of addiction is that the addict has a lack of self-control from something that has an awarding effect that keeps you coming back . The addicted party wants to abstain, but they can't resist the temptation. Addicts lose control over their actions. It is viewed that an addict battles with their addiction and wanting abstinence and gain control over their actions.

3.5K
03 Nov 2022

Topic Review

Since the early life of humankind on the Earth, nature represents the most powerful source for his major needs from food, energy, and therapeutics. Oceans cover more than 70% of Earth’s surface, and therefore, they continue to offer exceptional scaffolds improving the quality of human life. According to the National Oceanic and Atmospheric Administration (United States Department of Commerce), marine microbes represent 98% of ocean biomass. From more than 300,000 described organisms, 12,000 novel compounds have been discovered attracting great interest in the last decades. Marine macroalgae are rich sources of either sulfated or non-sulfated polysaccharides with a wide range of interesting medical applications. Fucoidan is a marine polysaccharide isolated mainly from brown macroalgae with interesting and promising pharmacological activities. Several articles discussed and proved the potential, versatile, and promising pharmacological activities of fucoidans.

3.5K
17 Dec 2020

Topic Review

Maladjustment is a term used in psychology to refer the "inability to react successfully and satisfactory to the demand of one's environment". The term maladjustment can be refer to a wide range of social, biological and psychological conditions. Maladjustment can be both intrinsic or extrinsic. Intrinsic maladjustment is the disparities between the needs, motivations and evaluations of an individual, with the actual reward gain through experiences. Extrinsic maladjustment on the other hand, is refer to when an individual's behavior is does not meet the cultural or social expectation of society. The causes of maladjustment can be attributed to a wide variety of factors, including: family environment, personal factors, and school-related factors. Maladjustment affects an individual's development and the ability to maintain a positive interpersonal relationship with others. Often maladjustment emerges during early stages of childhood, when a child is in the process of learning methods to solve problem that occurs in interpersonal relationship in their social network. A lack of intervention for individuals who are maladjusted can cause negative effects later on in life.

3.5K
30 Nov 2022

Topic Review Peer Reviewed

Mucormycosis—Emerging Fungal Threats

Mucormycosis is an opportunistic fungal infection due to organisms of the Zygomycetes class and the order of Mucorales that can cause various types of infections. In recent years, an increasing phenomenon has been observed—invasive fungal infections especially in the healthcare setting. Among immucompromised patients, an important clinical emergency could be represented by mucormycosis. The epidemiology of mucormycosis has shown an alarming trend and its incidence is rising globally. Four elements are fundamental for a successful treatment: rapid diagnosis, reduction of predisposing factors (if possible), surgical debridement of infected tissues, and appropriate antifungal therapy.

3.5K
13 Apr 2022

Topic Review

Jilly Juice is a quack pseudomedicine in the form of a fermented drink that is falsely claimed by its proponents to be able to cure an assortment of conditions, including cancer and autism spectrum disorders, as well as regenerate missing limbs, reverse the effects of aging, and "cure" homosexuality. No studies have proven any of these claims, nor has the Food and Drug Administration (FDA) approved the recipe. The juice, composed of water, salt, and fermented cabbage or kale, is falsely claimed to expunge Candida (a yeast) and parasitic worms. Scientific evidence has shown that this treatment is not only ineffective, but is also toxic with potentially deadly adverse effects.[lower-alpha 1] Jilly Juice was conceived by Jillian Mai Thi Epperly, who has no medical or scientific background. She has garnered media scrutiny for her baseless claims that Jilly Juice can help treat medical conditions, and petitions and other efforts have been made to ban the product and its promotion from social media. Followers of Epperly have been dubbed members of a "poop cult", and by 2017, had formed a now-defunct Facebook group made up of over 58,000 members. In 2018, the Federal Trade Commission (FTC) warned Epperly that it is against the law to advertise a product's health benefits without proper scientific support.

3.5K
04 Nov 2022

Topic Review

Eurabia is a political neologism, a portmanteau of Europe and Arabia, used to describe a far-right anti-Muslim conspiracy theory, involving globalist entities allegedly led by French and Arab powers, to Islamise and Arabise Europe, thereby weakening its existing culture and undermining a previous alignment with the United States and Israel. The term was first used in the 1970s as the title of a newsletter and the concept itself developed by Bat Ye'or (pen name of Gisèle Littman) in the early 2000s and is described in her 2005 book titled Eurabia: The Euro‐Arab Axis. Benjamin Lee of the Centre for Research and Evidence on Security Threats at the University of Lancaster describes her work as arguing that Europe "has surrendered to Islam and is in a state of submission (described as dhimmitude) in which Europe is forced to deny its own culture, stand silently by in the face of Muslim atrocities, accept Muslim immigration, and pay tribute through various types of economic assistance." According to the theory, the blame rests with a range of groups including communists, fascists, the media, universities, mosques and Islamic cultural centres, European bureaucrats, and the Euro-Arab Dialogue. The term has gained some public interest and has been used and discussed across a wide range of the political spectrum, including right-wing activists, self-described "conservatives" and counter-jihad and other anti-Islamism activists. Bat Ye'or's "mother conspiracy theory" has been used for further subtheories. The narrative grew important in expressing anti-Islamist sentiments and was used by movements like Stop Islamisation of Europe. It gained renewed interest after the September 11 attacks and the use of the term by 2011 Norway attacker, Anders Behring Breivik. Ye'or's thesis has come under criticism by scholars, which intensified after Breivik's crime. The conspiracy has been described as having resemblance to the anti-Semitic Protocols of the Elders of Zion. Eurabia is also discussed in classical anti-Europeanism, a strong influence in the culture of the United States and in the notion of American exceptionalism, which sometimes sees Europe on the decline or as a rising rival power, or, as is the case here, both.

3.5K
16 Nov 2022

Topic Review

Catenin beta-1, also known as β-catenin, is a protein that in humans is encoded by the CTNNB1 gene. β-catenin is a dual function protein, involved in regulation and coordination of cell–cell adhesion and gene transcription. In humans, the CTNNB1 protein is encoded by the CTNNB1 gene. In Drosophila, the homologous protein is called armadillo. β-catenin is a subunit of the cadherin protein complex and acts as an intracellular signal transducer in the Wnt signaling pathway. It is a member of the catenin protein family and homologous to γ-catenin, also known as plakoglobin. Beta-catenin is widely expressed in many tissues. In cardiac muscle, beta-catenin localizes to adherens junctions in intercalated disc structures, which are critical for electrical and mechanical coupling between adjacent cardiomyocytes. Mutations and overexpression of β-catenin are associated with many cancers, including hepatocellular carcinoma, colorectal carcinoma, lung cancer, malignant breast tumors, ovarian and endometrial cancer. Alterations in the localization and expression levels of beta-catenin have been associated with various forms of heart disease, including dilated cardiomyopathy. β-catenin is regulated and destroyed by the beta-catenin destruction complex, and in particular by the adenomatous polyposis coli (APC) protein, encoded by the tumour-suppressing APC gene. Therefore, genetic mutation of the APC gene is also strongly linked to cancers, and in particular colorectal cancer resulting from familial adenomatous polyposis (FAP).

3.5K
01 Dec 2022

Topic Review

Duckweed is the smallest and fastest-growing aquatic plant, and has advantages including simple processing and the ability to grow high biomass in smaller areas.

3.5K
20 Feb 2021

Topic Review

HVAC Systems of Smart Building

Early fault detection and diagnosis in heating, ventilation and air conditioning (HVAC) systems may reduce the damage of equipment, improving the reliability and safety of smart buildings, generating social and economic benefits. Data models for fault detection and diagnosis are increasingly used for extracting knowledge in the supervisory tasks. This article proposes an autonomic cycle of data analysis tasks (ACODAT) for the supervision of the building’s HVAC systems. Data analysis tasks incorporate data mining models for extracting knowledge from the system monitoring, analyzing abnormal situations and automatically identifying and taking corrective actions. This article shows a case study of a real building’s HVAC system, for the supervision with our ACODAT, where the HVAC subsystems have been installed over the years, providing a good example of a heterogeneous facility. The proposed supervisory functionality of the HVAC system is capable of detecting deviations, such as faults or gradual increment of energy consumption in similar working conditions. The case study shows this capability of the supervisory autonomic cycle, usually a key objective for smart buildings.

3.5K
01 Jun 2021

Topic Review

Res Publica Christiana

In medieval and early modern Western political thought, the respublica or res publica Christiana refers to the international community of Christian peoples and states. As a Latin phrase, res publica Christiana combines Christianity with the originally Roman idea of the res publica ("republic" or "commonwealth") to describe this community and its well-being. A single English word with somewhat comparable meaning is Christendom; it is also translated as "the Christian Commonwealth".

3.5K
18 Oct 2022

Topic Review

Christian Contemplation

Christian contemplation, from contemplatio (Latin; Greek θεωρία, theoria), refers to several Christian practices which aim at "looking at", "gazing at", "being aware of" God or the Divine. It includes several practices and theological concepts, and until the sixth century the practice of what is now called mysticism was referred to by the term contemplatio, c.q. theoria. Christianity took up the use of both the Greek (theoria) and Latin (contemplatio, contemplation) terminology to describe various forms of prayer and the process of coming to know God. Eastern and Western traditions of Christianity grew apart as they incorporated the general notion of theoria into their respective teachings. The Catechism of the Catholic Church states that, "the Christian tradition comprises three major expressions of the life of prayer: vocal prayer, meditation, and contemplative prayer. They have in common the recollection of the heart." Three stages are discerned in contemplative practice, namely purgative contemplation, contemplation proper, and the vision of God.

3.5K
28 Oct 2022

Topic Review

The phylum "Bacteroidetes" is composed of three large classes of Gram-negative, nonsporeforming, anaerobic or aerobic, and rod-shaped bacteria that are widely distributed in the environment, including in soil, sediments, and sea water, as well as in the guts and on the skin of animals. Although some Bacteroides spp. can be opportunistic pathogens, many "Bacteroidetes" are symbiotic species highly adjusted to the gastrointestinal tract. Bacteroides are highly abundant in intestines, reaching up to 1011 cells g−1 of intestinal material. They perform metabolic conversions that are essential for the host, such as degradation of proteins or complex sugar polymers. "Bacteroidetes" colonize the gastrointestinal tract already in infants, as non-digestible oligosaccharides in mother milk support the growth of both Bacteroides and Bifidobacterium spp. Bacteroides spp. are selectively recognized by the immune system of the host through specific interactions.

3.5K
21 Jul 2025

Topic Review

Time geography or time-space geography is an evolving transdisciplinary perspective on spatial and temporal processes and events such as social interaction, ecological interaction, social and environmental change, and biographies of individuals. Time geography "is not a subject area per se", but rather an integrative ontological framework and visual language in which space and time are basic dimensions of analysis of dynamic processes. Time geography was originally developed by human geographers, but today it is applied in multiple fields related to transportation, regional planning, geography, anthropology, time-use research, ecology, environmental science, and public health. According to Swedish geographer Bo Lenntorp: "It is a basic approach, and every researcher can connect it to theoretical considerations in her or his own way."

3.5K
13 Nov 2022

Topic Review

Pocket-Sized Computer

Pocket-sized computer describes the post-programmable calculator / pre-smartphone pocket-sized portable-office hardware devices that included the earlier DOS-based palmtops and subsequent Windows-CE handhelds, as well as a few other terms, primarily covering the 1980s through 2007. Sometimes called Pocket-sized computing devices, they were a series of internally different devices, and included Handheld ("Pocket-sized handheld computing device"), and the earlier-introduced Palmtop ("Pocket-sized palmtop computing device") and "pocket-sized palmtop computer." The New York Times used the term "palmtop/handheld." The media called "the first computer that fits in your palm and weighs less than a pound" and its early day competitors a palmtop. Although the word "handheld" was used before Microsoft's 1996 introduction of Windows CE, a lawsuit by Palm, Inc pushed Microsoft's use of the new term Handheld PC. By 2007, the iPhone began to replace prior portable office devices, and by a decade later there were indications that "SmartGlasses" might be their replacement.

3.5K
28 Nov 2022

Topic Review

Comparison of Different Types of Palatal Expanders

Maxillary bone contraction is caused by genetics or ambiental factors and is often accompanied by dental crowding, with the possibility of canine inclusion, crossbite, class II and III malocclusion, temporomandibular joint disorder, and obstructive sleep apnea (OSAS). Transverse maxillary deficits, in which the maxillary growth is unusually modest, are frequently treated with maxillary expansion. The purpose herein is to compare the dental and skeletal effects of different types of expanders, particularly the Leaf Expander, rapid and slow dental-anchored or skeletal-anchored maxillary expanders.

3.5K
04 Aug 2023

Page
of
2853

Featured Entry Collections

>>

Featured Reprints

>>

Encyclopedia of Digital Society, Industry 5.0 and Smart City

Encyclopedia of Digital Society, Industry 5.0 and Smart City
Chief Editor: Sandro Serpa

Encyclopedia of Engineering

Encyclopedia of Social Sciences

Encyclopedia of Social Sciences
Chief Editor: Kum Fai Yuen

Encyclopedia of Medieval Royal Iconography

Encyclopedia of Medieval Royal Iconography
Published Version (2022) >>
Chief Editor: Mirko Vagnoni

Academic Video Service

Feedback

Top