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Topic Review
Thin-Film Materials by RF Sputtering
We report on the development of several different thin-film material systems prepared by RF magnetron sputtering at Edith Cowan University nanofabrication labs. While focusing on the RF sputtering process optimizations for new or the previously underexplored material compositions and multilayer structures, we disclose several unforeseen material properties and behaviours. We communicate research results related to the design, prototyping, and practical fabrication of high-performance magneto-optic (MO) materials, oxide based sensor components, and transparent heat regulation coatings for advanced construction and solar windows.
  • 3.8K
  • 30 Oct 2020
Topic Review
Environmental Orientation and Environment Commitment
Environmental orientation reflects the extent to which employees recognize the legitimacy of environmental issues and the impact that the firm has on those issues. It is an essential part of the strategic disposition of any organization that translates into business operations and how operating in an environmentally sustainable way is perceived by different members of the organization. Environmental commitment practices ranged from having a formal environmental plan to a dedicated board or committee looking after the environmental issues. Drivers of environmental commitment can be identified on the continuum of internal to external drivers. The environmental orientation is one of the drivers of environmental commitment by firms as it can prompt the organizational leaders to take pro-environmental initiatives. When environmentalism is part of corporate identity, environmental commitment becomes a moral obligation.
  • 3.8K
  • 04 Aug 2021
Topic Review
Instituto Superior Técnico
Instituto Superior Técnico (IST, also known as TECNICO LISBOA) is a public school of engineering and technology , part of Universidade de Lisboa (University of Lisbon). Founded in 1911, IST is the largest and most prestigious school of engineering in Portugal, having a large degree of scientific and financial autonomy. Its alumni have held prominent positions in both the private and public sectors of Portuguese society, having produced numerous CEOs, government ministers, 2 Prime Ministers of Portugal, and 1 Secretary-General of the United Nations. Some Rankings: Instituto Superior Técnico - World's TOP 50 Eng Univ 2018 Instituto Superior Técnico. World's 8th Best Civil Eng Univ 2017 IST, since its foundation, has been the largest school of engineering, science and technology in Portugal, at undergraduate and postgraduate levels. It has three campi, all located in the Greater Lisbon area (Alameda in Lisbon, Taguspark in Oeiras and Tecnológico e Nuclear Campus in Loures), and consists of ten Departments that are responsible for teaching the undergraduate and postgraduate programmes. Each Department is organised in sections, which group together specific subjects within its scientific area. In addition, the laboratories of the several Departments are an important source of support to the teaching and research activities carried out at IST. IST offers 18 undergraduate programmes attended by more than 6,000 students, covering a wide range of areas of knowledge, including not only all the traditional engineering specializations, but also other modern areas such as Biomedical Engineering, Aerospace and Physics Engineering. Over 4,500 students are enrolled in 33 masters, 31 doctoral and several specialized programmes. IST has produced 1,292 Ph.D. holders. IST is also actively involved in several networks and international programmes to promote student mobility, both at undergraduate and postgraduate levels. Through a large number of agreements with other institutions worldwide, IST participates in more than 20 Dual Master programmes, and joint PhD programmes with MIT, CMU, UT-Austin and EPFL. IST benefits from an IBM supercomputer built in 2007, which is one of the most powerful in Portugal (1.6 TFLOPS as of 2007).
  • 3.8K
  • 30 Nov 2022
Topic Review
History of Life
The history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils. The similarities among all known present-day species indicate that they have diverged through the process of evolution from a common ancestor. Only a very small percentage of species have been identified: one estimate claims that Earth may have 1 trillion species. However, only 1.75–1.8 million have been named and 1.8 million documented in a central database. These currently living species represent less than one percent of all species that have ever lived on Earth. The earliest evidence of life comes from biogenic carbon signatures and stromatolite fossils discovered in 3.7 billion-year-old metasedimentary rocks from western Greenland. In 2015, possible "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. In March 2017, putative evidence of possibly the oldest forms of life on Earth was reported in the form of fossilized microorganisms discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada, that may have lived as early as 4.28 billion years ago, not long after the oceans formed 4.4 billion years ago, and not long after the formation of the Earth 4.54 billion years ago. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean Epoch and many of the major steps in early evolution are thought to have taken place in this environment. The evolution of photosynthesis, around 3.5 Ga, eventually led to a buildup of its waste product, oxygen, in the atmosphere, leading to the great oxygenation event, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles) dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions. Sexual reproduction, which involves the fusion of male and female reproductive cells (gametes) to create a zygote in a process called fertilization is, in contrast to asexual reproduction, the primary method of reproduction for the vast majority of macroscopic organisms, including almost all eukaryotes (which includes animals and plants). However the origin and evolution of sexual reproduction remain a puzzle for biologists though it did evolve from a common ancestor that was a single celled eukaryotic species. Bilateria, animals having a left and a right side that are mirror images of each other, appeared by 555 Ma (million years ago). Algae-like multicellular land plants are dated back even to about 1 billion years ago, although evidence suggests that microorganisms formed the earliest terrestrial ecosystems, at least 2.7 Ga. Microorganisms are thought to have paved the way for the inception of land plants in the Ordovician period. Land plants were so successful that they are thought to have contributed to the Late Devonian extinction event. (The long causal chain implied seems to involve the success of early tree archaeopteris (1) drew down CO2 levels, leading to global cooling and lowered sea levels, (2) roots of archeopteris fostered soil development which increased rock weathering, and the subsequent nutrient run-off may have triggered algal blooms resulting in anoxic events which caused marine-life die-offs. Marine species were the primary victims of the Late Devonian extinction.) Ediacara biota appear during the Ediacaran period, while vertebrates, along with most other modern phyla originated about 525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but most of this group became extinct in the Permian–Triassic extinction event 252 Ma. During the recovery from this catastrophe, archosaurs became the most abundant land vertebrates; one archosaur group, the dinosaurs, dominated the Jurassic and Cretaceous periods. After the Cretaceous–Paleogene extinction event 66 Ma killed off the non-avian dinosaurs, mammals increased rapidly in size and diversity. Such mass extinctions may have accelerated evolution by providing opportunities for new groups of organisms to diversify.
  • 3.8K
  • 18 Oct 2022
Topic Review
Cellulose and Cellulose Derivatives
Among the biomaterials, cellulose is the most abundant, cheap, sustainable, chemical reactive and modifiable natural macromolecular compound on the Earth. It is a carbohydrate homopolymer, which is composed of repeating long linear chains of β-anhydro-D-glucopyranose units, linked together by an ether bond between -OH group of C4, and the C1 carbon atom, via a β-1,4-glycosidic bond.
  • 3.8K
  • 10 Feb 2023
Topic Review
Enzymatic Transesterification in Biodiesel Production
       Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.        Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.
  • 3.8K
  • 30 Oct 2020
Topic Review
Grid Connected Photovoltaic Inverters
       The installation of photovoltaic (PV) system for electrical power generation has gained a substantial interest in the power system for clean and green energy. However, having the intermittent characteristics of photovoltaic, its integration with the power system may cause certain uncertainties (voltage fluctuations, harmonics in output waveforms, etc.) leading towards reliability and stability issues. In PV systems, the power electronics play a significant role in energy harvesting and the integration of grid-friendly power systems. Therefore, the reliability, efficiency, and cost-effectiveness of power converters are of main concern in the system design and are mainly dependent on the applied control strategy. 
  • 3.8K
  • 26 Aug 2020
Topic Review
88 Modern Constellations
In contemporary astronomy, the sky is divided into 88 regions called constellations, generally based on the asterisms (which are also called "constellations") of Greek and Roman mythology. The number of 88, along with the contemporary scientific notion of "constellation", was conventioned in 1922 by the International Astronomical Union in order to establish a universal pattern for professional astronomers, who defined constellations from then on as regions of the sky separated by arcs of right ascensions and declinations and grouped by asterisms of their historically most important stars, which cover the entire celestial sphere. The constellations along the ecliptic are called the zodiac. The ancient Sumerians, and later the Greeks (as recorded by Ptolemy), established most of the northern constellations in international use today. When explorers mapped the stars of the southern skies, European and American astronomers proposed new constellations for that region, as well as ones to fill gaps between the traditional constellations. Not all of these proposals caught on, but in 1922, the International Astronomical Union (IAU) adopted the modern list of 88 constellations. After this, Eugène Joseph Delporte drew up precise boundaries for each constellation, so that every point in the sky belonged to exactly one constellation.
  • 3.8K
  • 08 Oct 2022
Topic Review
Application of Zeolite in Cancer Therapy
Zeolites and zeolitic imidazolate frameworks (ZIFs) are widely studied as drug carrying nanoplatforms to enhance the specificity and efficacy of traditional anticancer drugs. 
  • 3.8K
  • 29 Dec 2021
Topic Review
Medical Implantable Antenna Technology
Implantable antennas are mandatory to transfer data from implants to the external world wirelessly. Smart implants can be used to monitor and diagnose the medical conditions of the patient. The dispersion of the dielectric constant of the tissues and variability of organ structures of the human body absorb most of the antenna radiation. 
  • 3.8K
  • 02 Jul 2021
Topic Review
Hydrogen Storage Technologies for Railway Engineering
According to the specific requirements of railway engineering, a techno-economic comparison for onboard hydrogen storage technologies is conducted to discuss their feasibility and potentials for hydrogen-powered hybrid trains. Physical storage methods, including compressed hydrogen (CH2), liquid hydrogen (LH2), and cryo-compressed hydrogen (CcH2), and material-based (chemical) storage methods, such as ammonia, liquid organic hydrogen carriages (LOHCs), and metal hydrides, are carefully discussed in terms of their operational conditions, energy capacity, and economic costs.
  • 3.8K
  • 23 Sep 2022
Topic Review
Scale Relativity
Scale relativity is a geometrical and fractal space-time physical theory. Relativity theories (special relativity and general relativity) are based on the notion that position, orientation, movement and acceleration cannot be defined in an absolute way, but only relative to a system of reference. The scale relativity theory proposes to extend the concept of relativity to physical scales (time, length, energy, or momentum scales), by introducing an explicit "state of scale" in coordinate systems. This extension of the relativity principle using fractal geometries to study scale transformations was originally introduced by Laurent Nottale, based on the idea of a fractal space-time theory first introduced by Garnet Ord, and by Nottale and Jean Schneider. The construction of the theory is similar to previous relativity theories, with three different levels: Galilean, special and general. The development of a full general scale relativity is not finished yet.
  • 3.8K
  • 14 Oct 2022
Topic Review
Application of PEDOT
Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is a highly important and attractive conducting polymer as well as commercially available in organic electronics, including electrochemical and electronic chemosensors, due to its unique features such as excellent solution-fabrication capability and miscibility, high and controllable conductivity, excellent chemical and electrochemical stability, good optical transparency and biocompatibility.
  • 3.8K
  • 26 Apr 2021
Topic Review
Monounsaturated Fat
In biochemistry and nutrition, monounsaturated fatty acids (abbreviated MUFAs, or more plainly monounsaturated fats) are fatty acids that have one double bond in the fatty acid chain with all of the remainder carbon atoms being single-bonded. By contrast, polyunsaturated fatty acids (PUFAs) have more than one double bond.
  • 3.8K
  • 30 Oct 2022
Topic Review
Poaching
Poaching has been defined as the illegal hunting or capturing of wild animals, usually associated with land use rights. According to Encyclopædia Britannica, poaching was performed by impoverished peasants for subsistence purposes and a supplement for meager diets. Poaching was as well set against the hunting privileges of nobility and territorial rulers. By contrast, stealing domestic animals (as in cattle raiding, for example) classifies as theft, not as poaching. Since the 1980s, the term "poaching" has also referred to the illegal harvesting of wild plant species. In agricultural terms, the term 'poaching' is also applied to the loss of soils or grass by the damaging action of feet of livestock which can affect availability of productive land, water pollution through increased runoff and welfare issues for cattle.
  • 3.8K
  • 24 Nov 2022
Topic Review
Rhinitis: Classification, Types, Pathophysiology
Rhinitis describes a pattern of symptoms as a result of nasal inflammation and/or dysfunction of the nasal mucosa. It is an umbrella entity that includes many different subtypes, several of which escape of complete characterization. Rhinitis is considered as a pathologic condition with considerable morbidity and financial burden on health care systems worldwide. Its economic impact is further emphasized by the fact that it represents a risk factor for other conditions such as sinusitis, asthma, learning disabilities, behavioral changes, and psychological impairment. Rhinitis may be associated with many etiologic triggers such as infections, immediate-type allergic responses, inhaled irritants, medications, hormonal disturbances, and neural system dysfunction. 
  • 3.8K
  • 01 Aug 2021
Topic Review
Wood-Eating Insects and Wood Eaters
Dead wood is rich in sugars and can serve as an energy source when digested, but it lacks other nutrients, preventing the growth, development, and maturation of saproxylophages. Prokaryotic N fixation partially mitigates the limitations on saproxylophages by the scarcity of N, often the most limiting nutrient, what does not mitigate co-limitation by other physiologically essential nutrients. Fungal transport can shape nutrient dynamics early in wood decay, rearranging extremely scarce nutritional composition of dead wood environment during its initial stage of decomposition and assisting saproxylophage growth and development. This nutritional enrichment of dead wood creates a nutritional niche for xylophages that allows them to grow, develop, and reach maturity. Therefore, xylophagous insects (considered as “wood-eaters”) are unable to gather the necessary amounts of nutritional elements from pure dead wood to grow and mature, but instead must utilize fungal tissues.
  • 3.8K
  • 30 Oct 2020
Topic Review
Salinity Stress in Plants
Plant growth and development is adversely affected by different kind of stresses. One of the major abiotic stresses, salinity, causes complex changes in plants by influencing the interactions of genes. 
  • 3.8K
  • 05 Feb 2021
Topic Review Video Peer Reviewed
Role of Happiness when Evaluating Society
Happiness, or life satisfaction, has become an important factor when considering what should be the objective of a society. Understanding the nature of happiness is thus important. The text offers a biological—specifically evolutionary—framework, which suggests that happiness can be described as the net impact of positive and negative feelings. It follows that a key issue is to explain what these feelings are about. The present situation and options for improving the score of happiness are discussed.
  • 3.8K
  • 13 Apr 2022
Topic Review
Nickel-Copper Alloys
Nickel-Copper (Ni-Cu) alloys exhibit simultaneously high strength and toughness (particularly, at cryogenic temperatures), excellent corrosion resistance, and may show good wear resistance. Therefore, they are widely used for manufacturing of (i) structural components of equipment in the chemical, oil, and marine industries, (ii) resistors and contacts in electrical and electronic equipment, (iii) corrosion resistant coatings, and (iv) fuel cells. Processing technologies includes bar forging, plate and tube rolling, wire drawing, heat treatment (for certain alloy compositions), powder and wire arc additive manufacturing, electrodeposition.
  • 3.8K
  • 26 Oct 2020
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