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Topic Review
Lithium-Ion Battery Fire Suppression
Lithium-ion Batteries (LiBs) hazards, techniques for mitigating risks, the suppression of LiB fires and identification of shortcomings for future improvement were thoroughly reviewed. Water is identified as an efficient cooling and suppressing agent and water mist is considered the most promising technique to extinguish LiBs fire. 
  • 6.6K
  • 29 Apr 2021
Topic Review
Design Challenges and Limitations of Injectable Hydrogels
Injectable hydrogels (IHs) are smart biomaterials and are the most widely investigated and versatile technologies, which can be either implanted or inserted into living bodies with minimal invasion. Their unique features, tunable structure and stimuli-responsive biodegradation properties make these IHs promising in many biomedical applications, including tissue engineering, regenerative medicines, implants, drug/protein/gene delivery, cancer treatment, aesthetic corrections and spinal fusions. Regarding their current prospective and ongoing research, hydrogel formulations have some limitations in their applications, clinical practices and sustainability. Many hydrogel systems (natural/synthetic), such as thermosensitive hydrogels, are free-flowing sols at a low temperature, while upon raising to body temperature (physiological temperature), they are converted to a stable visco-elastic gel phase, such as poly (phosphazene), pluronic and poly (N-isopropyl acrylamide). 
  • 6.6K
  • 08 Apr 2022
Topic Review
Gaia Hypothesis
The Gaia hypothesis (/ˈɡaɪ.ə/), also known as the Gaia theory, Gaia paradigm, or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet. The hypothesis was formulated by the chemist James Lovelock and co-developed by the microbiologist Lynn Margulis in the 1970s. Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. The suggestion that the theory should be called "the Gaia hypothesis" came from Lovelock's neighbour, William Golding. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis. Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth. The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.
  • 6.6K
  • 07 Nov 2022
Topic Review
Iridology
Iridology (also known as iridodiagnosis or iridiagnosis) is an alternative medicine technique whose proponents claim that patterns, colors, and other characteristics of the iris can be examined to determine information about a patient's systemic health. Practitioners match their observations to iris charts, which divide the iris into zones that correspond to specific parts of the human body. Iridologists see the eyes as "windows" into the body's state of health. Iridologists claim they can use the charts to distinguish between healthy systems and organs in the body and those that are overactive, inflamed, or distressed. Iridologists claim this information demonstrates a patient's susceptibility towards certain illnesses, reflects past medical problems, or predicts later health problems. As opposed to evidence-based medicine, iridology is not supported by quality research studies and is widely considered pseudoscience. The features of the iris are one of the most stable features on the human body throughout life. The stability of iris structures is the foundation of the biometric technology which uses iris recognition for identification purposes. In 1979, Bernard Jensen, a leading American iridologist, and two other iridology proponents failed to establish the basis of their practice when they examined photographs of the eyes of 143 patients in an attempt to determine which ones had kidney impairments. Of the patients, forty-eight had been diagnosed with kidney disease, and the rest had normal kidney function. Based on their analysis of the patients' irises, the three iridologists could not detect which patients had kidney disease and which did not.
  • 6.6K
  • 04 Nov 2022
Topic Review
Bureaucracy
Bureaucracy is a concept that refers to a formal organizational structure characterized by a hierarchical arrangement of tasks, authority, and responsibilities. Rooted in the principles of efficiency, rationality, and specialization, bureaucracy represents a system of administration designed to streamline decision-making processes, facilitate coordination, and ensure the efficient functioning of complex organizations. The term is often associated with administrative entities, government agencies, and large corporations, where intricate tasks require systematic management.
  • 6.6K
  • 25 Jan 2024
Topic Review Peer Reviewed
Solar Chimney Applications in Buildings
A solar chimney is a renewable energy system used to enhance the natural ventilation in a building based on solar and wind energy. It is one of the most representative solar-assisted passive ventilation systems attached to the building envelope. It performs exceptionally in enhancing natural ventilation and improving thermal comfort under certain climate conditions. The ventilation enhancement of solar chimneys has been widely studied numerically and experimentally. The assessment of solar chimney systems based on buoyancy ventilation relies heavily on the natural environment, experimental environment, and performance prediction methods, bringing great difficulties to quantitative analysis and parameterization research. With the increase in volume and complexity of modern building structures, current studies of solar chimneys have not yet obtained a unified design strategy and corresponding guidance. Meanwhile, combining a solar chimney with other passive ventilation systems has attracted much attention. The solar chimney-based integrated passive-assisted ventilation systems prolong the service life of an independent system and strengthen the ventilation ability for indoor cooling and heating. However, the progress is still slow regarding expanded applications and related research of solar chimneys in large volume and multi-layer buildings, and contradictory conclusions appear due to the inherent complexity of the system.
  • 6.6K
  • 13 Apr 2022
Topic Review
Traditional Chinese Timekeeping
The traditional Chinese time systems refers to the time standards for divisions of the day used in China until the introduction of the Shixian calendar in 1628 at the beginning of the Qing dynasty.
  • 6.6K
  • 30 Oct 2022
Topic Review Peer Reviewed
Cuteness and Its Emotional Responses
Cuteness is commonly associated with visual features such as large eyes, a disproportionately large head, round body shapes, and small size. While these traits are most often observed in infants and young animals, they also appear in inanimate objects and digital representations intentionally designed to evoke emotional appeal. Drawing on developmental psychology, behavioral science, neuroscience, and cultural studies, this paper examines five core emotional responses to cute stimuli: caretaking, socializing, whimsical, cute aggression, and kama muta (the feeling of being emotionally moved). These responses emerge from an interplay between evolutionary mechanisms, such as caregiving instincts, and cultural frameworks that shape how cuteness is perceived, expressed, and valued. The analysis highlights not only biological foundations but also cultural moderators, with particular attention to gender differences and the pervasive role of kawaii aesthetics in Japan’s popular culture, communication, and everyday life. This paper provides an overview of these emotional responses, situates them within their theoretical foundations and broader psychological and social implications, and proposes a framework for future research.
  • 6.6K
  • 17 Sep 2025
Topic Review
Plant-Mediated Nanoparticle Synthesis
The green synthesis of nanoparticles(NPs) is gaining attention owing to its facilitation of the development of alternative, sustainable, safer, less toxic and environment-friendly approaches. Thus, green nanotechnology using plant extract opens up new possibilities for the synthesis of novel nanoparticles with the desirable characteristics required for developing biosensors, biomedicine, cosmetics and nano-biotechnology, and in electrochemical, catalytic, antibacterial, electronics, sensing and other applications. 
  • 6.6K
  • 02 Mar 2022
Topic Review
β-Adrenergic Stimulation
β-adrenergic receptor stimulation (β-ARS) is a physiological mechanism that regulates cardiovascular function under stress conditions or physical exercise, producing a positive inotropic (enhanced contraction), lusitropic (faster relaxation), and chronotropic (increased heart rate) effect. 
  • 6.6K
  • 04 Aug 2021
Topic Review
Transmission Dynamics of COVID-19
COVID-19 is pneumonia caused by a novel coronavirus which is an emerging infectious disease, and outbreaks in more than 200 countries around the world. Consequently, the spread principles and prevention and control measures of COVID-19 have become a global problem to be solved. Here, we pose a series of dynamical models to reveal the transmission mechanisms of COVID-19. Based on these mathematical models, data fitting and spread trend of COVID-19 are explored to show the propagation law between human populations. We hope that our work may provide some useful insights for effective control of the COVID-19.
  • 6.6K
  • 28 Oct 2020
Topic Review
Keto–Enol Tautomerism
In organic chemistry, keto–enol tautomerism refers to a chemical equilibrium between a keto form (a ketone or an aldehyde) and an enol (an alcohol). The keto and enol forms are said to be tautomers of each other. The interconversion of the two forms involves the movement of an alpha hydrogen atom and the reorganisation of bonding electrons; hence, the isomerism qualifies as tautomerism. A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important for some reactions. The deprotonated intermediate in the interconversion of the two forms, referred to as an enolate anion, is important in carbonyl chemistry, in large part because it is a strong nucleophile. Normally, the keto–enol tautomerization chemical equilibrium is highly thermodynamically driven, and at room temperature the equilibrium heavily favors the formation of the keto form. A classic example for favoring the keto form can be seen in the equilibrium between vinyl alcohol and acetaldehyde (K = [enol]/[keto] ≈ 3 × 10−7). However, it is reported that in the case of vinyl alcohol, formation of a stabilized enol form can be accomplished by controlling the water concentration in the system and utilizing the kinetic favorability of the deuterium-produced kinetic isotope effect (kH+/kD+ = 4.75, kH2O/kD2O = 12). Deuterium stabilization can be accomplished through hydrolysis of a ketene precursor in the presence of a slight stoichiometric excess of heavy water (D2O). Studies show that the tautomerization process is significantly inhibited at ambient temperatures ( kt ≈ 10−6 M/s), and the half-life of the enol form can easily be increased to t1/2 = 42 minutes for first-order hydrolysis kinetics. Another exception is the 1,3-diketones, such as acetylacetone (2,4-pentanedione), which favor the enol form.
  • 6.6K
  • 24 Oct 2022
Topic Review
Sesquiterpene Lactones
Sesquiterpene lactones, a vast group of terpenoids isolated from Asteraceae family species, exhibit a wide variety of biological activities and several of them are already available on the medicines market, such as artemisinin. Here are presented and discussed the most recent and impactful results in vivo, preclinical and clinical studies, involving a selection of ten sesquiterpene lactones (alantolactone, arglabin, costunolide, cynaropicrin, helenalin, inuviscolide, lactucin, parthenolide, thapsigargin and tomentosin) and some of their derivatives.
  • 6.6K
  • 28 Oct 2020
Topic Review
2010–14 Portuguese Financial Crisis
2010–14 Portuguese financial crisis was part of the more wider downturn of the Portuguese economy that started in 2001 and possibly ended in 2016–17. The period from 2010 to 2014 was probably the hardest and more challenging part of the entire economic crisis; this period includes the 2011–14 international bailout to Portugal and was marked by an intense austerity policy, intenser than in any other period of the wider 2001–17 crisis. Economic growth stalled in Portugal in 2001–02; following years of internal economic crisis, the (international) Great Recession started to hit Portugal in 2008 and eventually led to the country being unable to repay or refinance its government debt without the assistance of third parties. To prevent an insolvency situation in the debt crisis, Portugal applied in April 2011 for bail-out programs and drew a cumulated €78.0 billion from the International Monetary Fund (IMF), the European Financial Stabilisation Mechanism (EFSM), and the European Financial Stability Facility (EFSF). Portugal leaved bailout in May 2014, the same year that positive economic growth re-appeared following three years of recession. The government achieved a 2.1% budget deficit in 2016 (the lowest since the restoration of democracy in 1974) and in 2017 the economy grew 2.7% (the highest growth rate since 2000). Greece and Ireland also went into a debt crisis in 2010. Together these debt crisis of these three countries marked the start of the European sovereign debt crisis.
  • 6.6K
  • 06 Oct 2022
Topic Review
LGBT Social Movements
Lesbian, gay, bisexual, and transgender (LGBT) social movements are social movements that advocate for LGBT people in society. Social movements may focus on equal rights, such as the 2000s movement for same-sex marriage, or they may focus on liberation, as in the gay liberation movement of the 1960s and 1970s. Earlier movements focused on self-help and self-acceptance, such as the homophile movement of the 1950s. Although there is not a primary or an overarching central organization that represents all LGBT people and their interests, numerous LGBT rights organizations are active worldwide. The earliest organizations to support LGBT rights were formed in the early 20th century. A commonly stated goal among these movements is social equality for LGBT people, but there is still denial of full LGBT rights. Some have also focused on building LGBT communities or worked towards liberation for the broader society from biphobia, homophobia, and transphobia. There is a struggle for LGBT rights today. LGBT movements organized today are made up of a wide range of political activism and cultural activity, including lobbying, street marches, social groups, media, art, and research.
  • 6.6K
  • 11 Nov 2022
Topic Review
Flocculus (Cerebellar)
The flocculus (Latin: tuft of wool, diminutive) is a small lobe of the cerebellum at the posterior border of the middle cerebellar peduncle anterior to the biventer lobule. Like other parts of the cerebellum, the flocculus is involved in motor control. It is an essential part of the vestibulo-ocular reflex, and aids in the learning of basic motor skills in the brain. It is associated with the nodulus of the vermis; together, these two structures compose the vestibular part of the cerebellum. At its base, the flocculus receives input from the inner ear's vestibular system and regulates balance. Many floccular projections connect to the motor nuclei involved in control of eye movement.
  • 6.6K
  • 02 Nov 2022
Topic Review
Material Extrusion Additive Manufacturing of Metal
Material extrusion additive manufacturing of metal (metal MEX), which is one of the 3D printing processes, has gained more interests because of its simplicity and economics. Metal MEX process is similar to the conventional metal injection moulding (MIM) process, consisting of feedstock preparation of metal powder and polymer binders, layer-by-layer 3D printing (metal MEX) or injection (MIM) to create green parts, debinding to remove the binders and sintering to create the consolidated metallic parts.
  • 6.6K
  • 02 Jun 2022
Topic Review
Paradigm Shift
A paradigm shift refers to a fundamental change in the underlying assumptions, beliefs, or frameworks that guide a particular field of knowledge or practice. It represents a transformative departure from established models of thought, leading to a reevaluation of existing principles and often opening new avenues for understanding and problem-solving within that domain.
  • 6.6K
  • 25 Jan 2024
Topic Review
Artificial Flower
Artificial flowers are imitations of natural flowering plants used for commercial or residential decoration. They are sometimes made for scientific purposes (the collection of glass flowers at Harvard University, for example, illustrates the flora of the United States). Artificial plants vary widely from mass-produced varieties that are distinguishable from real plants by casual observation to highly detailed botanical or artistic specimens. Materials used in their manufacture have included painted linen and shavings of stained horn in ancient Egypt, gold and silver in ancient Rome, rice-paper in China , silkworm cocoons in Italy, colored feathers in South America, and wax and tinted shells. Modern techniques involve carved or formed soap, nylon netting stretched over wire frames, ground clay, and mass-produced injection plastic mouldings. Polyester has been the main material for manufacturing artificial flowers since the 1970s. Most artificial flowers in the market nowadays are made of polyester fabric.
  • 6.6K
  • 05 Sep 2025
Topic Review
Technology and Society
Technology society and life or technology and culture refers to the inter-dependency, co-dependence, co-influence, and co-production of technology and society upon one another. Evidence for this synergy has been found since humanity first started using simple tools. The inter-relationship has continued as modern technologies such as the printing press and computers have helped shape society. The first scientific approach to this relationship occurred with the development of tektology, the "science of organization", in early twentieth century Imperial Russia. In modern academia, the interdisciplinary study of the mutual impacts of science, technology, and society, is called science and technology studies. The simplest form of technology is the development and use of basic tools. The prehistoric discovery of how to control fire and the later Neolithic Revolution increased the available sources of food, and the invention of the wheel helped humans to travel in and control their environment. Developments in historic times have lessened physical barriers to communication and allowed humans to interact freely on a global scale, such as the printing press, telephone, and Internet. Technology has developed advanced economies, such as the modern global economy, and has led to the rise of a leisure class. Many technological processes produce by-products known as pollution, and deplete natural resources to the detriment of Earth's environment. Innovations influence the values of society and raise new questions in the ethics of technology. Examples include the rise of the notion of efficiency in terms of human productivity, and the challenges of bioethics. Philosophical debates have arisen over the use of technology, with disagreements over whether technology improves the human condition or worsens it. Neo-Luddism, anarcho-primitivism, and similar reactionary movements criticize the pervasiveness of technology, arguing that it harms the environment and alienates people. However, proponents of ideologies such as transhumanism and techno-progressivism view continued technological progress as beneficial to society and the human condition.
  • 6.6K
  • 24 Nov 2022
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