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Topic Review
Lifshitz Theory of Van Der Waals Force
In condensed matter physics and physical chemistry, the Lifshitz theory of van der Waals forces, sometimes called the macroscopic theory of van der Waals forces, is a method proposed by Evgeny Mikhailovich Lifshitz in 1954 for treating van der Waals forces between bodies which does not assume pairwise additivity of the individual intermolecular forces; that is to say, the theory takes into account the influence of neighboring molecules on the interaction between every pair of molecules located in the two bodies, rather than treating each pair independently.
  • 3.1K
  • 03 Nov 2022
Topic Review
Informal Learning
Informal learning is characterized “by a low degree of planning and organizing in terms of the learning context, learning support, learning time, and learning objectives”. It differs from formal learning, non-formal learning, and self-regulated learning, because it has no set objective in terms of learning outcomes, but an intent to act from the learner’s standpoint (e.g., to solve a problem). Typical mechanisms of informal learning include trial and error or learning-by-doing, modeling, feedback, and reflection. For learners this includes heuristic language building, socialization, enculturation, and play. Informal learning is a pervasive ongoing phenomenon of learning via participation or learning via knowledge creation, in contrast with the traditional view of teacher-centered learning via knowledge acquisition. Estimates suggest that about 70-90 percent of adult learning takes place informally and outside educational institutions. The term is often conflated, however, with non-formal learning, and self-directed learning. It is widely used in the context of corporate training and education in relation to return on investment (ROI), or return on learning (ROL). It is also widely used when referring to science education, in relation to citizen science, or informal science education. The conflated meaning of informal and non-formal learning explicates mechanisms of learning that organically occur outside the realm of traditional instructor-led programs, e.g., reading self-selected books, participating in self-study programs, navigating performance support materials and systems, incidental skills practice, receptivity of coaching or mentoring, seeking advice from peers, or participation in communities of practice, to name a few. Informal learning is common in communities where individuals have opportunities to observe and participate in social activities. Advantages of informal learning cited include flexibility and adaptation to learning needs, direct transfer of learning into practice, and rapid resolution of (work-related) problems. For improving employees' performance, task execution is considered the most important source of learning.
  • 3.1K
  • 12 Dec 2022
Topic Review
Volumetric Muscle Loss
Volumetric muscle loss (VML) is the massive wasting of skeletal muscle tissue due to traumatic events or surgical ablation. This pathological condition exceeds the physiological healing process carried out by the muscle itself, which owns remarkable capacity to restore damages but only when limited in dimensions. Upon VML occurring, the affected area is severely compromised, heavily influencing the affected person’s quality of life. Overall, this condition is often associated with chronic disability, which makes the return to duty of highly specialized professional figures (e.g., military personnel or athletes) almost impossible. The actual treatment for VML is based on surgical conservative treatment followed by physical exercise; nevertheless, the results, in terms of either lost mass and/or functionality recovery, are still poor. On the other hand, the efforts of the scientific community are focusing on reconstructive therapy aiming at muscular tissue void volume replenishment by exploiting biomimetic matrix or artificial tissue implantation. Reconstructing strategies represent a valid option to build new muscular tissue not only to recover damaged muscles, but also to better socket prosthesis in terms of anchorage surfaces and reinnervation substrates for reconstructed mass. 
  • 3.1K
  • 26 May 2021
Topic Review
Land Use Transitions
Land use transition refers to the changes in land use morphologies, including dominant morphology and recessive morphology, of a certain region over a certain period of time driven by socio-economic change and innovation, and it usually corresponds to the transformation of the socio-economic development stage. The dominant morphology refers to the land use structure with features such as the quantity and spatial pattern of land use types. While the recessive morphology includes the land use features in the aspects of quality, property rights, management mode, input, output and function.
  • 3.1K
  • 17 Sep 2021
Topic Review
In-Wheel Motor Drive Systems for Electric Vehicles
There has been significant attention given to the electrification of transportation due to concerns about fossil fuel depletion and environmental pollution. Conventional drive systems typically include a clutch, reduction gear, and mechanical differential, which results in power loss, noise, vibration, and additional maintenance. However, in-wheel motor drive technology eliminates the need for these components, providing benefits such as higher system efficiency, improved wheel control, and increased passenger comfort.
  • 3.1K
  • 21 Aug 2023
Topic Review
Dolomite as a Filler in a Polymer Composite
Polymers are being used in many applications all around the world. However, there are some drawbacks in the properties of polymers that could hamper their usage in certain applications. Therefore, a new material polymer composite was introduced. A polymer composite is a polymer-based material with the addition of a filler. Many researchers have reported the improvement in the properties of a polymer when a filler was introduced. This helps minimize the disadvantages of using a polymer. Fillers are materials added to resins or binders (polymer/concrete/metal/ceramic) to improve their specific properties as they are turned into a new form of material called a “composite.” Dolomite is a type of sedimentary carbonate rock that consists mainly of dolomite mineral. The use of dolomite in a polymer composite system has gained increasing attention in recent years after researchers successfully proved that it is capable of improving mechanical and physical properties of various polymeric materials. 
  • 3.1K
  • 09 Aug 2022
Topic Review
Book of Dzyan
The Book of Dzyan (comprising the Stanzas of Dzyan) is a reputedly ancient text of Tibetan origin. The Stanzas formed the basis for The Secret Doctrine (1888), one of the foundational works of the theosophical movement, by Helena Petrovna Blavatsky.
  • 3.0K
  • 21 Nov 2022
Topic Review
Applications of Facial Scanners in Dentistry
Facial scanning accuracy has proven to be clinically acceptable for use in dental applications. Accuracy is measured by comparing the scan to a control model and measuring the deviations between the two. Scanners with deviation values less than 2 mm are considered acceptable. Deviation values for facial scanners range between 140 and 1330 μm. Reported accuracy for most facial scanners was approximately 500 μm, which is within the limits for clinical acceptability. 
  • 3.0K
  • 06 Dec 2022
Topic Review
Q'eqchi' Language
The Q'eqchi' language, also spelled Kekchi, K'ekchi', or kekchí, is one of the Mayan languages, spoken within Q'eqchi' communities in Guatemala and Belize.
  • 3.0K
  • 14 Oct 2022
Topic Review
Microalga Haematococcus pluvialis
The freshwater microalga Haematococcus pluvialis is well known as the cell factory for natural astaxanthin, which composes up to 4–7% of its total dry weight. The bioaccumulation of astaxanthin in H. pluvialis cysts seems to be a very complex process that depends on different stress conditions during its cultivation. The red cysts of H. pluvialis develop thick and rigid cell walls under stress growing conditions.
  • 3.0K
  • 03 Mar 2023
Topic Review
Mushroom Poisoning
Mushroom poisoning is poisoning resulting from the ingestion of mushrooms that contain toxic substances. Its symptoms can vary from slight gastrointestinal discomfort to death in about 10 days. Mushroom toxins are secondary metabolites produced by the fungus. Mushroom poisoning is usually the result of ingestion of wild mushrooms after misidentification of a toxic mushroom as an edible species. The most common reason for this misidentification is a close resemblance in terms of color and general morphology of the toxic mushrooms species with edible species. To prevent mushroom poisoning, mushroom gatherers familiarize themselves with the mushrooms they intend to collect, as well as with any similar-looking toxic species. The safety of eating wild mushrooms may depend on methods of preparation for cooking.
  • 3.0K
  • 19 Oct 2022
Topic Review
Contributions of Chromatography to the Science Progress
Chromatography was born approximately one century ago and has undergone outstanding technological improvements in innovation, research, and development since then that has made it fundamental to advances in knowledge at different levels, with a relevant impact on the well-being and health of individuals. Chromatography boosted a comprehensive and deeper understanding of the complexity and diversity of human–environment interactions and systems, how these interactions affect our life, and the several societal challenges currently facing, namely those related to the sustainability of our planet and the future generations. From the life sciences, which allowed to identify endogenous metabolites relevant to disease mechanisms, to the OMICS field, nanotechnology, clinical and forensic analysis, drug discovery, environment, and “foodprint”, among others, the wide range of applications of today’s chromatographic techniques is impressive. This is fueled by a great variability of powerful chromatographic instruments currently available, with very high sensitivity, resolution, and identification capacity, that provide a strong basis for an analytical platform able to support the challenging demands of the postgenomic and post COVID-19 eras. 
  • 3.0K
  • 02 Sep 2022
Biography
Michel de Montaigne
Michel Eyquem de Montaigne (/mɒnˈteɪn/ mon-TAYN;[1] French: [miʃɛl ekɛm də mɔ̃tɛɲ]; 28 February 1533 – 13 September 1592[2]), also known as Lord of Montaigne, was one of the most significant philosophers of the French Renaissance. He is known for popularizing the essay as a literary genre. His work is noted for its merging of casual anecdotes[3] and autobiography with intellectual
  • 3.0K
  • 05 Dec 2022
Topic Review
Weichselian Glaciation
Weichselian glaciation[upper-alpha 1] refers to the last glacial period and its associated glaciation in northern parts of Europe. In the Alpine region it corresponds to the Würm glaciation. It was characterized by a large ice sheet (the Fenno-Scandian ice sheet) that spread out from the Scandinavian Mountains and extended as far as the east coast of Schleswig-Holstein, the March of Brandenburg and Northwest Russia. In Northern Europe it was the youngest of the glacials of the Pleistocene ice age. The preceding warm period in this region was the Eemian interglacial. The last cold period began about 115,000 years ago and ended 11,700 years ago. Its end corresponds with the end of the Pleistocene epoch and the start of the Holocene. The German geologist Konrad Keilhack (de) (1858-1944) named Weichselian glaciation using the German-language name (Weichsel) of the River Vistula (Polish: Wisła) in present-day Poland.
  • 3.0K
  • 14 Oct 2022
Topic Review
Secondary Marine Metabolites
Secondary marine metabolites are defined as molecules with a molecular weight ranging between 100 to 1000 Da and, unlike primary marine metabolites, are often found to be unique to an organism or a specific taxonomic group of the marine source. Other than marine macroorganisms such as algae, sponges, or corals, specifically marine fungi and bacteria have shown to produce novel secondary metabolites with unique as well as diverse chemical structures that may hold the key for developing novel drugs or drug leads. Secondary marine metabolites have been found in both prokaryotic and eukaryotic microorganisms, with unicellular bacteria (e.g., Bacillus sp., Pseudomonas sp.), eukaryotic fungi (e.g., Penicillium sp., Aspergillus sp.), filamentous actinomyces (e.g., Streptomyces sp.), and terrestrial plants being the most frequently studied and versatile producers. A potential clarification why organisms produce a high assortment of bioactive secondary marine metabolites is that these molecules furnish producers with a specific advantage against competing organisms and, furthermore, act as an adaptation to ecological conditions.
  • 3.0K
  • 30 Sep 2020
Topic Review
Permanent Magnet Synchronous Motor
The most common special features and demands of the PMSMs are described in the appearance of the motor’s failures caused by uncontrolled temperature rise. In addition, heat sources and energy losses, including copper loss, core loss versus motor speed, and output power, are analyzed. Various cooling strategies are listed and discussed. Scope of this review is to develop PMSM for a heavy duty green mobility with the smart light weight materials and with the enhanced cooling approaches.
  • 3.0K
  • 30 Mar 2021
Topic Review
Solution-Processed Organic Phototransistors and Their Recent Developments
Today, more disciplines are intercepting each other, giving rise to “cross-disciplinary” research. Technological advancements in material science and device structure and production have paved the way towards development of new classes of multi-purpose sensory devices. Organic phototransistors (OPTs) are photo-activated sensors based on organic field-effect transistors that convert incident light signals into electrical signals. The organic semiconductor (OSC) layer and three-electrode structure of an OPT offer great advantages for light detection compared to conventional photodetectors and photodiodes, due to their signal amplification and noise reduction characteristics. Solution processing of the active layer enables mass production of OPT devices at significantly reduced cost. The chemical structure of OSCs can be modified accordingly to fulfil detection at various wavelengths for different purposes. Organic phototransistors have attracted substantial interest in a variety of fields, namely biomedical, medical diagnostics, healthcare, energy, security, and environmental monitoring. Lightweight and mechanically flexible and wearable OPTs are suitable alternatives not only at clinical levels but also for point-of-care and home-assisted usage.
  • 3.0K
  • 27 Jan 2022
Topic Review
International Council of Societies of Industrial Design
The International Council of Societies of Industrial Design (Icsid) was founded in 1957 from a group of international organizations focused on industrial design. Today Icsid is a worldwide society that promotes better design around the world, and has since been renamed the World Design Organization in January 2017. Today, WDO includes over 140 member organizations in more than 40 nations, representing an estimated 150,000 designers. The primary aim of the association is to advance the discipline of industrial design at an international level. To do this, WDO undertakes a number of initiatives of global appeal to support the effectiveness of industrial design in an attempt to address the needs and aspirations of people around the world, to improve the quality of life, as well as help to improve the economy of nations throughout the world. WDO holds United Nations Special Consultative Status which empowers them to make change, and works towards addressing the United Nations Sustainable Development Goals.
  • 3.0K
  • 29 Nov 2022
Topic Review
Strain Rate Sensitivity
Strain rate is a parameter related with dynamic loading phenomena, which are common in industrial applications.
  • 3.0K
  • 06 Sep 2021
Topic Review
High-Dynamic-Range Imaging
In photography and videography, HDR or high-dynamic-range imaging is the set of techniques used to reproduce a greater range of luminosity than that which is possible with standard photographic techniques. Standard techniques allow differentiation only within a certain range of brightness. Outside this range, no features are visible because in the brighter areas everything appears pure white, and pure black in the darker areas. The ratio between the maximum and the minimum of the tonal value in an image is known as the dynamic range. HDR is useful for recording many real-world scenes containing very bright, direct sunlight to extreme shade, or very faint nebulae. High-dynamic-range (HDR) images are often created by capturing and then combining several different, narrower range, exposures of the same subject matter. The two primary types of HDR images are computer renderings and images resulting from merging multiple low-dynamic-range (LDR) or standard-dynamic-range (SDR) photographs. HDR images can also be acquired using special image sensors, such as an oversampled binary image sensor. Due to the limitations of printing and display contrast, the extended luminosity range of input HDR images has to be compressed to be made visible. The method of rendering an HDR image to a standard monitor or printing device is called tone mapping. This method reduces the overall contrast of an HDR image to facilitate display on devices or printouts with lower dynamic range, and can be applied to produce images with preserved local contrast (or exaggerated for artistic effect). "HDR" may refer to the overall process, to the HDR imaging process, or to HDR imaging represented on a low-dynamic-range display such as a screen or standard .jpg image.
  • 3.0K
  • 28 Oct 2022
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