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Topic Review
Pliny the Younger on Christians
Pliny the Younger, the Roman governor of Bithynia et Pontus (now in modern Turkey) wrote a letter to Emperor Trajan around 112 AD and asked for counsel on dealing with Christians. The letter (Epistulae X.96) details an account of how Pliny conducted trials of suspected Christians who appeared before him as a result of anonymous accusations and asks for the Emperor's guidance on how they should be treated. Neither Pliny nor Trajan mentions the crime that Christians had committed, except for being a Christian; and other historical sources do not provide a simple answer to what that crime could be, but a likely element may be the stubborn refusal of Christians to worship Roman gods; making them appear as objecting to Roman rule. Pliny states that he gives Christians multiple chances to affirm they are innocent and if they refuse three times, they are executed. Pliny states that his investigations have revealed nothing on the Christians' part but harmless practices and "depraved, excessive superstition." However, Pliny seems concerned about the rapid spread of this "superstition"; and views Christian gatherings as a potential starting point for sedition. The letter is the first pagan account to refer to Christianity, providing key information on early Christian beliefs and practices and how these were viewed and dealt with by the Romans. The letter and Trajan's reply indicate that at the time of its writing there was no systematic and official Empire-wide persecution of Christians. Trajan's reply also offers valuable insight into the relationship between Roman provincial governors and Emperors and indicates that at the time Christians were not sought out or tracked down by imperial orders, and that persecutions could be local and sporadic.
  • 4.9K
  • 14 Nov 2022
Topic Review
Non-invasive Imaging Technology
Non-invasive imaging technology is a commonly used diagnostic tool in modern medicine. Commonly used are computed tomography (CT), positron emission tomography (PET), ultrasound (US), PAI (photoacoustic imaging) and MRI (magnetic resonance imaging) . This review explores the use of these modalities for imaging biodegradable implants.
  • 4.9K
  • 27 Jul 2021
Topic Review
Submarine Cables Radial Water Barrier
The submarine cables manufacturing industry is growing very rapidly. Solutions used so far, usually adapted from designs of land cables, do not fulfil the new, more demanding requirements. The phenomenon of water ingress into insulation and its absorption are basic factors determining the service life of submarine cables. The radial water barrier is the only effective component of cable design that may guarantee the required minimum 30-year longevity of submarine cables.
  • 4.9K
  • 01 Jun 2021
Topic Review
Epoxide Synthesis and Ring-Opening Reactions
This entry concentrates on some examples of success stories from the synthesis of approved medicines and drug candidates using epoxide chemistry in the development of robust and efficient syntheses at large scale. The focus is on those parts of each synthesis related to the substrate-controlled/diastereoselective and catalytic asymmetric synthesis of epoxide intermediates and their subsequent ring-opening reactions with various nucleophiles. These are described in the form of case studies of high profile pharmaceuticals spanning a diverse range of indications and molecular scaffolds such as heterocycles, terpenes, steroids, peptidomimetics, alkaloids and main stream small molecules. Representative examples include, but are not limited to the antihypertensive diltiazem, the antidepressant reboxetine, the HIV protease inhibitors atazanavir and indinavir, efinaconazole and related triazole antifungals, tasimelteon for sleep disorders, the anticancer agent carfilzomib, the anticoagulant rivaroxaban the antibiotic linezolid and the antiviral oseltamivir. Emphasis is given on aspects of catalytic asymmetric epoxidation employing metals with chiral ligands particularly with the Sharpless and Jacobsen–Katsuki methods as well as organocatalysts such as the chiral ketones of Shi and Yang, Pages's chiral iminium salts and typical chiral phase transfer agents.
  • 4.9K
  • 09 Oct 2020
Topic Review
Pathophysiology of Osteoporosis
Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss.
  • 4.9K
  • 15 Nov 2022
Topic Review
Drone Detection and Defense Systems
Drones are small and low-cost unmanned aerial vehicles (UAVs). With the decrease in the cost and size of drones in recent years, their number has also increased exponentially. As such, the concerns regarding security aspects that are raised by their presence are also becoming more serious.
  • 4.9K
  • 10 Mar 2022
Topic Review
Thomson Reuters Business Classification
The Thomson Reuters Business Classification (TRBC) is an industry classification of global companies, developed in 2004; it is owned and operated by Thomson Reuters and is also the basis for Thomson Reuters Indices.
  • 4.9K
  • 28 Nov 2022
Topic Review
Laser Powder Bed Fusion
Laser powder bed fusion (LPBF) is the most used metal additive manufacturing technique, and it is based on the efficient interaction between a high-energy laser and a metal powder feedstock. The reuse of the powder feedstock is crucial to make the process cost-efficient and environmentally friendly. However, since studies of the mechanical and microstructural properties of parts produced with reused powders show scattered results, a closer look to the powder, heat source and shielding gas properties and to how they interact during the LPBF process is presented.  
  • 4.9K
  • 29 Oct 2020
Topic Review
Biosynthesis Pathway and Metabolism of Isoflavones
Isoflavones have been widely studied and have attracted extensive attention in fields ranging from chemotaxonomy and plant physiology to human nutrition and medicine. Isoflavones are often divided into three subgroups: simple O-substituted derivatives, prenylated derivatives, and glycosides. Simple O-substituted isoflavones and their glycosides, such as daidzein (daidzin), genistein (genistin), glycitein (glycitin), biochanin A (astroside), and formononetin (ononin), are the most common ingredients in legumes and are considered as phytoestrogens for daily dietary hormone replacement therapy due to their structural similarity to 17-β-estradiol. On the basis of the known estrogen-like potency, these above isoflavones possess multiple pharmacological activities such as antioxidant, anti-inflammatory, anticancer, anti-angiogenetic, hepatoprotective, antidiabetic, antilipidemic, anti-osteoporotic, and neuroprotective activities. 
  • 4.9K
  • 22 Sep 2022
Topic Review
False Position Method
In mathematics, the false position method or regula falsi is a very old method for solving an equation in one unknown, that, in modified form, is still in use. In simple terms, the method is the trial and error technique of using test ("false") values for the variable and then adjusting the test value according to the outcome. This is sometimes also referred to as "guess and check". Versions of the method predate the advent of algebra and the use of equations. As an example, consider problem 26 in the Rhind papyrus, which asks for a solution of (written in modern notation) the equation x + x/4 = 15. This is solved by false position, using a technique that predates formally written equations. First, guess that x = 4 to obtain, on the left, 4 + 4/4 = 5. This guess is a good choice since it produces an integer value. However, 4 is not the solution of the original equation, as it gives a value which is three times too small. To compensate, multiply x (currently set to 4) by 3 and substitute again to get 12 + 12/4 = 15, verifying that the solution is x = 12. Modern versions of the technique employ systematic ways of choosing new test values and are concerned with the questions of whether or not an approximation to a solution can be obtained, and if it can, how fast can the approximation be found.
  • 4.9K
  • 15 Nov 2022
Topic Review
Monkeypox Virus
Monkeypox virus (MPXV) is a double-stranded DNA virus belonging to the Orthopox genus in the family Poxviridae. It has a zoonotic origin and MPXV infected wild rodents and primates have been found in central Africa. In humans, symptoms of MPXV infection include fever, head and muscle ache, lymphadenopathy and a characteristic rash that develops into papules, vesicles and pustules which eventually scab over and heal. Monkeypox is less often fatal (case fatality rates range from less than 1% to 3.6% depending on geographic localisation, viral clade and age group) than smallpox (up to 30%) caused by a related Variola virus. MPXV used to be endemic in sub-Saharan Africa, infecting wild animals and occasionally causing zoonotic outbreaks. Exotic animal trade and international travel combined with the increasing susceptibility of the human population due to lack of vaccination facilitated the spread of MPXV to new areas. Since April 2022, over 15.000 of MPX cases have been detected in >60 non-endemic countries around the world, predominantly among men who have sex with men, making it the largest described MPXV outbreak known to date.
  • 4.9K
  • 21 Jul 2022
Topic Review
Anti-Fungal Efficacy of Flavonoids
The prevalence of fungal infections is growing at an alarming pace and the pathogenesis is still not clearly understood. Recurrence of these fungal diseases is often due to their evolutionary avoidance of antifungal resistance. The development of suitable novel antimicrobial agents for fungal diseases continues to be a major problem in the current clinical field. Hence, it is urgently necessary to develop surrogate agents that are more effective than conventional available drugs. Among the remarkable innovations from earlier investigations on natural-drugs, flavonoids are a group of plant-derived substances capable of promoting many valuable effects on humans. The identification of flavonoids with possible antifungal effects at small concentrations or in synergistic combinations could help to overcome this problem. A combination of flavonoids with available drugs is an excellent approach to reduce the side effects and toxicity.
  • 4.9K
  • 10 Jun 2021
Topic Review
Carbon-Based Quantum Dots for Supercapacitors
Carbon-based Quantum dots (C-QDs) are carbon-based materials that experience the quantum confinement effect, which results in superior optoelectronic properties. In recent years, C-QDs have attracted attention significantly and have shown great application potential as a high-performance supercapacitor device. C-QDs (either as a bare electrode or composite) give a new way to boost supercapacitor performances in higher specific capacitance, high energy density, and good durability. This review comprehensively summarizes the up-to-date progress in C-QD applications either in a bare condition or as a composite with other materials for supercapacitors. The current state of the three distinct C-QD families used for supercapacitors including carbon quantum dots, carbon dots, and graphene quantum dots is highlighted. 
  • 4.9K
  • 28 Sep 2021
Topic Review
Psychoneuroendocrineimmunology (PNEI)
Psychoneuroendocrineimmunology (PNEI) brings together knowledge acquired since the 1930s from endocrinology, immunology, neuroscience, and psychology. With PNEI, a model of research and interpretation of health and disease is emerging, which sees the human body as a structured and interconnected unit, where the psychological and biological systems are mutually coordinated. In the PNEI view, many factors could influence mental health, with the endocrine system involved in mediating the effects of environmental stress on mental health and inflammation in the onset and course of psychiatric disorders as a result of individual and collective conditions and behaviors.  PNEI paradigm configures the possibilities of going beyond the historical and philosophical contrast between mind and body, as well as the scientific antithesis of the twentieth century, between medicine and psychology, overcoming their respective reductionism, which assigns the body to the first and the psyche to the second.   
  • 4.9K
  • 11 Aug 2021
Topic Review
Coping (Psychology)
In psychology, coping means to invest own conscious effort, to solve personal and interpersonal problems, in order to try to master, minimize or tolerate stress and conflict. The psychological coping mechanisms are commonly termed coping strategies or coping skills. The term coping generally refers to adaptive (constructive) coping strategies. That is strategies which reduce stress. In contrast, other coping strategies may be coined as maladaptive, if they increase stress. Maladaptive coping is therefore also described, when looking at the outcome, as non-coping. Furthermore, the term coping generally refers to reactive coping, i.e. the coping response which follows the stressor. This differs from proactive coping, in which a coping response aims to neutralize a future stressor. Subconscious or non-conscious strategies (e.g. defense mechanisms) are generally excluded from the area of coping. The effectiveness of the coping effort depends on the type of stress, the individual, and the circumstances. Coping responses are partly controlled by personality (habitual traits), but also partly by the social environment, particularly the nature of the stressful environment.
  • 4.9K
  • 17 Oct 2022
Topic Review
Intercultural Competence
Intercultural competence is a range of cognitive, affective, and behavioural skills that lead to effective and appropriate communication with people of other cultures. Effective intercultural communication relates to behaviors that culminate with the accomplishment of the desired goals of the interaction and all parties involved in the situation. Appropriate intercultural communication includes behaviors that suit the expectations of a specific culture, the characteristics of the situation, and the level of the relationship between the parties involved in the situation. It also takes into consideration one's own cultural norms and the best appropriate, comfortable compromise between the different cultural norms. It's very important for someone to be culturally competent at work and at school. Individuals that are effective and appropriate in intercultural situations display high levels of cultural self-awareness and understand the influence of culture on behavior, values, and beliefs. Intercultural competence is achieved through a set of skills that includes cognitive, affective, and behavioral processes. Cognitive processes imply the understanding of situational and environmental aspects of intercultural interactions and the application of intercultural awareness, which is affected by the understanding of the self and own culture. Self-awareness in intercultural situations refers to the ability of self-monitoring in such interactions to censor anything not acceptable to another culture. On the other hand, cultural awareness leads the individual to an understanding of how his/her own culture determines feelings, thoughts, and personality. Affective processes define the emotions that span during intercultural interactions. These emotions are strongly related to self-concept, open-mindedness, non-judgementalism, and social relaxation. In general, positive emotions generate respect for other cultures and their differences. Behavioral processes refer to how effectively and appropriately the individual directs actions to achieve goals. Actions during intercultural interactions are influenced by the ability to clearly convey a message, proficiency with the foreign language, flexibility and management of behavior, and social skills.
  • 4.9K
  • 26 Oct 2022
Topic Review
Scientific Tourism
Scientific tourism (ST) is a transversal approach to tourism development and management that can be applied in the evolution of many segments, from rural, to ecotourism or mass tourism.  ST focuses on contributing to the resilience of communities and territories by building shared knowledge and understanding of essential socio-ecological characteristics and dynamics.  The website of the ST network (scientific-tourism.org), defines ST as an activity where visitors participate in the generation and dissemination of scientific knowledge being developed by research and development centers. Mao and Bourlon described ST using a spectrum of levels and thematic approaches, organized around the four overarching categories: (1) adventure tourism with a scientific dimension, (2) cultural tourism with a scientific dimension, (3) scientific eco-volunteering, and (4) scientific research-based tourism. The authors suggested that, in many cases, the four forms of ST were complementary, and could simultaneously occur or merge within the scope of a destination or project. While this approach to ST incorporates many of the concepts of learning tourism, it differs in that it is grounded in the perspective of scientific knowledge generation and dissemination. Scientific tourism (ST) development builds on the scientific heritage of a geography, by matching researchers with local actors in an ongoing process that leads to shared understanding and the creation of new knowledge that can support the conservation and resilience of communities and their natural and socio-cultural settings. Through purposeful grounding of tourism in science, local communities can become more engaged with the socio-ecological systems in which they live and become empowered to innovate the ways in which tourism evolves.
  • 4.9K
  • 23 Sep 2021
Topic Review
CYP3A4
CYP3A4 is a low specificity isoenzyme of the CYPs family, which contributes to the metabolism of approximately 50% of all marketed drugs. Induction or inhibition of CYP3A4 activity results in the varied oral bioavailability and unwanted drug-drug, drug-food, and drug-herb interactions.
  • 4.9K
  • 01 Sep 2021
Topic Review
Dome C
Dome C, also known as Dome Circe, Dome Charlie or Dome Concordia, located at Antarctica at an elevation of 3,233 metres (10,607 ft) above sea level, is one of several summits or "domes" of the Antarctic Ice Sheet. Dome C is located on the Antarctic Plateau, 1,100 kilometres (680 mi) inland from the French research station at Dumont D'Urville, 1,100 kilometres (680 mi) inland from the Australian Casey Station and 1,200 kilometres (750 mi) inland from the Italian Zucchelli station at Terra Nova Bay. Russia's Vostok Station is 560 kilometres (350 mi) away. Dome C is the site of the Concordia Research Station, jointly operated by France and Italy.
  • 4.9K
  • 04 Nov 2022
Topic Review
The Resilient City
A resilient city can be defined as a community that has the capacity to manage unexpected events and face stresses and shocks, preserving and innovating its social, economic, and infrastructural system.
  • 4.9K
  • 21 Jul 2021
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