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Topic Review
Historic Timber Structures with Stainless Steel
The use of stainless steel components, particularly in new constructions, has experienced a huge increase in recent times. Stainless steel is now widely used for both non-structural applications and as ribbed reinforcement bars for concrete, members (beams, columns, ties, etc.) in trusses, bridges and buildings. Similar to structural carbon steel, stainless steel elements can be hot rolled and fabricated or cold rolled formed. 
  • 2.6K
  • 28 Mar 2022
Topic Review
European Green Deal
The European Green Deal, approved 2020, is a set of policy initiatives by the European Commission with the overarching aim of making the European Union (EU) climate neutral in 2050. An impact assessed plan will also be presented to increase the EU's greenhouse gas emission reductions target for 2030 to at least 50% and towards 55% compared with 1990 levels. The plan is to review each existing law on its climate merits, and also introduce new legislation on the circular economy, building renovation, biodiversity, farming and innovation. The president of the European Commission, Ursula von der Leyen, stated that the European Green Deal would be Europe's "man on the moon moment". Von der Leyen appointed Frans Timmermans as Executive Vice President of the European Commission for the European Green Deal. On 13 December 2019, the European Council decided to press ahead with the plan, with an opt-out for Poland . On 15 January 2020, the European Parliament voted to support the deal as well, with requests for higher ambition. The European Commission's climate change strategy, launched in 2020, is focused on a promise to make Europe a net-zero emitter of greenhouse gases by 2050 and to demonstrate that economies will develop without increasing resource usage. However, the Green Deal has measures to ensure that nations that are already reliant on fossil fuels are not left behind in the transition to renewable energy.
  • 2.6K
  • 21 Oct 2022
Topic Review
Applications of Smart Drug Delivery Devices
The internet of things (IoT) plays a vital role in smart drug delivery systems. It is an emerging field that offers promising solutions for improving the efficacy, safety, and patient compliance of drug therapies. IoT-based drug delivery systems leverage advanced devices, sophisticated sensors, and smart tools to monitor and analyse the health matrices of the patient in real-time, allowing for personalised and targeted drug delivery. This technology is implemented through various types of devices, including wearable and implantable devices such as infusion pumps, smart pens, inhalers, and auto-injectors. However, the development and implementation of IoT-based drug delivery systems pose several challenges, such as ensuring data security and privacy, regulatory compliance, compatibility, and reliability.
  • 2.6K
  • 10 Jul 2023
Topic Review
Paeonia Suffruticosa
Paeonia suffruticosa is a name used for a group of culture varieties of tree peonies that are the result of hybridisation with species exclusively belonging to the subsection Vaginatae. The common name used in China is mǔdān (Chinese: 牡丹). Plants belonging to this group have been cultivated for millennia in China, initially only as a source of traditional Chinese medicine particularly the skin of its roots (牡丹皮; mǔdān pí). Already early on the plant was also cultivated for its ornamental value, and it is highly revered in Chinese culture.
  • 2.6K
  • 30 Nov 2022
Topic Review
Cost-Effective Zinc–Iron Redox Flow Batteries
Zinc–iron redox flow batteries (ZIRFBs) possess intrinsic safety and stability and have low electrolyte cost. ZBRFB refers to an redox flow batterie (RFB) in which zinc is used as the electrochemically active substance in the electrolyte solutions. The zinc electrode has a reversible anode potential. Zinc ions are stable in both alkaline and acidic environments, even in a neutral electrolyte, and the electrochemical reaction rate is relatively fast. 
  • 2.6K
  • 08 Dec 2022
Topic Review
GVL Production with Levulinic Acid
Levulinic acid (LA) is considered as one of the “Top 10” building blocks for future bio-refineries as proposed by the US Department of Energy. It is  one of the most important platform molecules for the production of fine chemicals and fuels based on its compatibility with existing processes, market economics, and industrial ability to serve as a platform for the synthesis of important derivatives. Hydrogenation of LA to produce γ-valerolactone (GVL) is an active area of research due to the potential of GVL to be used as a biofuel in its own right and for its subsequent transformation into hydrocarbon fuels. This paper contains a new design for a simple, cost effective, and safe hydrogenation reactor for the transformation of levulinic acid to γ-valerolactone (GVL) by utilizing high boiling point organic fluid. The hydrogenation reactor is composed of a heating source—organic fluid (called “DOWTHERM A” or “thermex”) and the catalytic reactor. The advantages of high boiling temperature fluids, along with advances in hydrocracking and reforming technologies driven by the oil and gas industries, make the organic concept more suitable and safer (water coming in contact with liquid metal is well understood in the metallurgical industry to be a steam explosion hazard) for heating the hydrogenation reactor. COMSOL multi-physics software version 4.3b was applied in this work and simultaneously solves the continuity, Navier-Stokes (fluid flow), energy (heat transfer), and diffusion with chemical reaction kinetics equations. It was shown that the heat flux supplied by the DOWTHERM A organic fluid could provide the necessary heat flux required for maintaining the hydrogenation process. It was found that the mass fractions of hydrogen and levulinic acid decreased along the reactor axis. The GVL mass fraction increased along the reactor axis.
  • 2.6K
  • 30 Oct 2020
Topic Review
Christian Republic
A Christian republic is a government that is both Christian and republican. Jean-Jacques Rousseau and John Locke considered the idea to be an impossibility and a self-contradiction, but for different reasons. As of the 21st century, the only countries in the world with a republican form of government and with Christianity as the established religion are Argentina, Costa Rica, Finland, Greece, Armenia, Samoa, Iceland, and Malta. Some other republics, such as Georgia, Peru, Guatemala, Panama, El Salvador, and Paraguay, give some credit or preference to Christianity, but without establishing it as the religion of the state. Others, such as Hungary, and Zambia, describe themselves as Christian countries. In A Letter Concerning Toleration, Locke wrote that "there is absolutely no such thing, under the Gospel, as a Christian Commonwealth". By this he meant that political authority cannot be validly founded upon Christianity. Rousseau, in On the Social Contract (in book 4, chapter 8), echoed this, saying that "I am mistaken in saying 'a Christian republic'; the two words are mutually exclusive.". However, Rousseau's point was subtly different, in that he was asserting that a civic identity cannot be moulded out of Christianity. David Walsh, founder of the National Institute on Media and the Family, acknowledges that there is a "genuine tension ... between Christianity and the political order" that Rousseau was acknowledging, arguing that "many Christians would, after all, agree with him that a 'Christian republic' is a contradiction in terms" and that the two live "in an uneasy relationship in actual states, and social cohesion has often been bought at the price of Christian universalism". Robert Neelly Bellah has observed that most of the great republican theorists of the Western world have shared Rousseau's concerns about the mutually exclusive nature of republicanism and Christianity, from Machiavelli (more on which later) to Alexis de Tocqueville. Rousseau's thesis is that the two are incompatible because they make different demands upon the virtuous man. Christianity, according to Rousseau, demands submission (variously termed "servitude" or "slavery" by scholars of his work) to imposed authority and resignation, and requires focus upon the unworldly; whereas republicanism demands participation rather than submission, and requires focus upon the worldly. Rousseau's position on Christianity is not universally held. Indeed, it was refuted by, amongst others, his friend Antoine-Jacques Roustan in a reply to the Social Contract. Rousseau's thesis has a basis in the prior writings of Niccolò Machiavelli, whom Rousseau called a "bon citoyen et honnête homme" and who alongside Montesquieu was one of Rousseau's sources for republican philosophy. In his Discoursi Machiavelli observes that Christianity in practice has not met the ideals of its foundation, and that the resultant corruption leads, when mixed with secular political ideals, to something that is neither good religion nor good politics. Further, he argues, whilst Christianity does not preclude love for one's country, it does require citizens to endure damage to republican government, stating that the best civic virtue in regards to a republic is to show no mercy to the republic's enemies and to put to death or to enslave the inhabitants of an opposing city that has been defeated.
  • 2.6K
  • 14 Oct 2022
Topic Review
Cyanobacteria
Cyanobacteria (blue-green microalgae) are ubiquitous, Gram-negative photoautotrophic prokaryotes. They are considered as one of the most efficient sources of bioactive secondary metabolites.
  • 2.6K
  • 15 Jan 2021
Topic Review
The Belt and Road Initiative
The Belt and Road Initiative (BRI), proposed by Chinese President Xi Jinping in 2013, is an international initiative with vital implications for the economy, society, culture, and the environment. Consisting of the "Silk Road Economic Belt" and the "21st Century Maritime Silk Road", the BRI was inherited and developed from the ancient Silk Road that played an essential role in connecting the West with the East on various socio-economic levels with its spirit of peace, friendship, inclusiveness, openness, and mutual benefit for many centuries.
  • 2.6K
  • 30 May 2022
Topic Review
Secret Chiefs
In various occult movements, Secret Chiefs are said to be transcendent cosmic authorities, a spiritual hierarchy responsible for the operation and moral calibre of the cosmos, or for overseeing the operations of an esoteric organization that manifests outwardly in the form of a magical order or lodge system. Their names and descriptions have varied through time, dependent upon those who reflect their experience of contact with them. They are variously held to exist on higher planes of being or to be incarnate; if incarnate, they may be described as being gathered at some special location, such as Shambhala, or scattered through the world working anonymously. One early and influential source on these entities is Karl von Eckartshausen, whose The Cloud upon the Sanctuary, published in 1795, explained in some detail their character and motivations. Several 19th and 20th century occultists claimed to belong to or to have contacted these Secret Chiefs and made these communications known to others, including H.P. Blavatsky (who called them the "Tibetan Masters" or Mahatmas), C.W. Leadbeater and Alice A. Bailey (who called them Masters of the Ancient Wisdom), Guy Ballard and Elizabeth Clare Prophet (who called them Ascended Masters)[citation needed], Aleister Crowley (who used the term to refer to members of the upper three grades of his order, A∴A∴), Dion Fortune (who called them the "esoteric order"), and Max Heindel (who called them the "Elder Brothers").
  • 2.6K
  • 29 Nov 2022
Topic Review
Legume Use in Extrusion Cooking
The traditional perception that legumes would not be suitable for extrusion cooking is now completely outdated. In the recent years an increasing number of researches have been conducted to assess the behavior of various types of legume flours in extrusion cooking, proving that legumes have excellent potential for the production of extruded ready-to-eat foods by partially or totally replacing cereals. There are optimal processing conditions for legume-based and legume-added extruded foods, which allow to improve the expansion ratio and give the extrudates the spongy and crisp structure expected by consumers. The extrusion cooking process has also a positive effect on the nutritional characteristics of legumes, because induces important modifications on starch and proteins, enhancing their digestibility, and reduces the content of trypsin inhibitors, lectins, phytic acid, and tannins. Therefore, the extrusion of legume flours is a viable strategy to improve their nutritional features while reducing home preparation time, so as to increase the consumption of these sustainable crops.
  • 2.6K
  • 27 Oct 2020
Topic Review
Nitric Oxide in Stem Cell Biology
Nitric oxide (NO) is a highly reactive gas with a brief life span, synthesized by the enzyme nitric oxide synthase (NOS) through L-arginine oxidation to L-citrulline. The dual role of NO in embryonic stem cells (ESCs) has been previously reported, preserving pluripotency and cell survival or inducing differentiation with a dose-dependent pattern. In this line, high doses of NO have been used in vitro cultures to induce focused differentiation toward different cell lineages being a key molecule in the regenerative medicine field. Moreover, optimal conditions to promote pluripotency in vitro are essential for their use in advanced therapies.
  • 2.6K
  • 15 Apr 2022
Topic Review
Extraction of Polycyclic Aromatic Hydrocarbons from Environmental Samples
Polycyclic aromatic hydrocarbons (PAHs) comprise a group of chemical compounds consisting of two or more fused benzene rings. PAHs exhibit hydrophobicity and low water solubility, while some of their members are toxic substances resistant to degradation. Due to their low levels in environmental matrices, a preconcentration step is usually required for their determination. Nowadays, there is a wide variety of sample preparation techniques, including micro-extraction techniques (e.g., solid-phase microextraction and liquid phase microextraction) and miniaturized extraction techniques (e.g., dispersive solid-phase extraction, magnetic solid-phase extraction, stir bar sorptive extraction, fabric phase sorptive extraction etc.). 
  • 2.6K
  • 02 Aug 2022
Topic Review
War on Women
War on Women is a slogan in United States politics used to describe certain Republican Party policies and legislation as a wide-scale effort to restrict women's rights, especially reproductive rights. Prominent Democrats such as Nancy Pelosi and Barbara Boxer, as well as feminists, have used the phrase to criticize proponents of these laws as trying to force their social views on women through legislation. The slogan has been used to describe Republican policies in areas such as access to reproductive health services, particularly birth control and abortion services; the prosecution of criminal violence against women; the definition of rape for the purpose of the public funding of abortion; and workplace discrimination against women. While used in other contexts, and prior to 2010, it became a common slogan in American political discourse after the 2010 congressional elections. The term is often used to describe opposition to the contraceptive mandate in Obamacare and policies to defund women's health organizations that perform abortions, such as Planned Parenthood. The concept again gained attention in the 2016 U.S. presidential election, when Republican nominee Donald Trump drew notice for a history of inflammatory statements and actions toward women. The phrase and the concept have been criticized by Republicans and some pro-life Democrats. Republican National Committee chairman Reince Priebus described it as an over-simplified fiction advanced by Democrats and the media while other Republicans contended that such rhetoric was used as a distraction from President Barack Obama and the Democrats' handling of the economy. In August 2012, Todd Akin's controversial comments regarding pregnancy and rape sparked renewed media focus on the concept. Republicans have tried to turn the phrase against Democrats by using it to argue hypocrisy for not critiquing sex scandals of members within their Party who have cheated, sexted, and harassed women; and for not supporting bills to combat sex-selective abortion.
  • 2.6K
  • 07 Nov 2022
Topic Review
Lugnut (Transformers)
Lugnut is the name of several fictional characters from the Transformers universe. Both are Decepticon jets who are loyal to Megatron.
  • 2.6K
  • 18 Nov 2022
Topic Review
Grain Boundary Sliding
Grain Boundary Sliding (GBS) is a material deformation mechanism where grains slide against each other. This occurs in polycrystalline material under external stress at high homologous temperature (above ~0.4) and low strain rate and is intertwined with creep. Homologous temperature describes the operating temperature relative to the melting temperature of the material. There are mainly two types of grain boundary sliding: Rachinger sliding, and Lifshitz sliding. Grain boundary sliding usually occurs as a combination of both types of sliding. Boundary shape often determines the rate and extent of grain boundary sliding. Many people have developed estimations for the contribution of grain boundary sliding to the total strain experienced by various groups of materials, such as metals, ceramics, and geological materials. Grain boundary sliding contributes a significant amount of strain, especially for fine grain materials and high temperatures. It has been shown that Lifshitz grain boundary sliding contributes about 50-60% of strain in Nabarro-Herring diffusion creep. This mechanism is the primary cause of ceramic failure at high temperatures due to the formation of glassy phases at their grain boundaries. 
  • 2.6K
  • 30 Nov 2022
Topic Review
Cyclops (Genus)
Cyclops is one of the most common genera of freshwater copepods, comprising over 400 species. Together with other similar-sized non-copepod fresh-water crustaceans, especially cladocera, they are commonly called water fleas. The name Cyclops comes from the Cyclops of Greek mythology which shares the quality of having a single large eye, which may be either red or black in Cyclops.
  • 2.6K
  • 14 Oct 2022
Topic Review
Lead (Pb)
Human exposure to lead can occur in a variety of ways, all of which involve exposure to potentially toxic elements as environmental pollutants. Lead enters the body via ingestion and inhalation from sources such as soil, food, lead dust and lead in products of everyday use and in the workplace. The aim of this review is to describe the toxic effects of lead on the human body from conception to adulthood, and to review the situation regarding lead toxicity in Poland. Results: Pb is very dangerous when it is absorbed and accumulates in the main organs of the body, where it can cause a range of symptoms that vary from person to person, the time of exposure and dose. Lead in adults can cause an increase in blood pressure, slow nerve conduction, fatigue, mood swings, drowsiness, impaired concentration, fertility disorders, decreased sex drive, headaches, constipation and, in severe cases, encephalopathy or death. Conclusions: Exposure to lead in Poland remains an important public health problem. This review will cover the range of lead exposures, from mild to heavy. Public health interventions and policies also are needed to reduce occupational and environmental exposure to this element.
  • 2.6K
  • 05 Nov 2020
Topic Review
Patagonian Berries
In this review, we focus on five fruit species growing in Patagonia with high potential as a functional food (i.e., maqui, murta, calafate, arrayán, and Chilean strawberry); giving a little background on the fruit quality; and discussing the recent research data available—regarding the particular compound profile, their processing, and clinical assays— of these Patagonian berries.
  • 2.6K
  • 01 Jul 2021
Topic Review
Current Virtual Inertia Topologies
The use of power electronic inverters leads to the dissociation of sources and loads and lowering the power system inertia. Under power imbalance, this drop causes an elevated rate of change in frequency and frequency divergences, which has a notable impact on the system’s frequency stability. As a result, enhanced control techniques for grid-tied electronic converters are required to secure the power system’s stability and support. The virtual-synchronous generator (VSG) control is used to mimic the dynamics of a rotating synchronous generator and improve the power system’s stability.
  • 2.6K
  • 30 Nov 2022
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