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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.
  • 3.9K
  • 10 Feb 2023
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
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
Sexual Identity
Sexual identity is how one thinks of oneself in terms of to whom one is romantically or sexually attracted. Sexual identity may also refer to sexual orientation identity, which is when people identify or dis-identify with a sexual orientation or choose not to identify with a sexual orientation. Sexual identity and sexual behavior are closely related to sexual orientation, but they are distinguished, with identity referring to an individual's conception of themselves, behavior referring to actual sexual acts performed by the individual, and sexual orientation referring to romantic or sexual attractions toward persons of the opposite sex or gender, the same sex or gender, to both sexes or more than one gender, or to no one. Historical models of sexual identity have tended to view its formation as a process undergone only by sexual minorities, while more contemporary models view the process as far more universal and attempt to present sexual identity within the larger scope of other major identity theories and processes.
  • 3.8K
  • 25 Oct 2022
Topic Review
Industrialization
Industrialization is the process of transforming an economy from primarily agrarian and manual labor-based into one dominated by manufacturing and industry. It involves the widespread adoption of mechanized production methods, the establishment of factories, and the utilization of advanced technologies to increase productivity. This societal shift, historically associated with the 18th and 19th centuries, has profound implications for economic structures, labor markets, and overall societal development.
  • 3.8K
  • 25 Jan 2024
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
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
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
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
Low-GWP Refrigerants (Pure and Blended)
Low global warming potential (GWP) refrigerants for the next-generation air conditioning systems have been investigated with target domestic applications. High-GWP refrigerants are mostly used in climate control applications such as heating, ventilation and air conditioning (HVAC) and refrigeration systems. 
  • 3.8K
  • 15 Nov 2022
Topic Review
Other
In phenomenology, the terms the Other and the Constitutive Other identify the other human being, in their differences from the Self, as being a cumulative, constituting factor in the self-image of a person; as acknowledgement of being real; hence, the Other is dissimilar to and the opposite of the Self, of Us, and of the Same. The Constitutive Other is the relation between the personality (essential nature) and the person (body) of a human being; the relation of essential and superficial characteristics of personal identity that corresponds to the relationship between opposite, but correlative, characteristics of the Self, because the difference is inner-difference, within the Self. The condition and quality of Otherness (the characteristics of the Other) is the state of being different from and alien to the social identity of a person and to the identity of the Self. In the discourse of philosophy, the term Otherness identifies and refers to the characteristics of Who? and What? of the Other, which are distinct and separate from the Symbolic order of things; from the Real (the authentic and unchangeable); from the æsthetic (art, beauty, taste); from political philosophy; from social norms and social identity; and from the Self. Therefore, the condition of Otherness is a person's non-conformity to and with the social norms of society; and Otherness is the condition of disenfranchisement (political exclusion), effected either by the State or by the social institutions (e.g., the professions) invested with the corresponding socio-political power. Therefore, the imposition of Otherness alienates the person labelled as "the Other" from the centre of society, and places him or her at the margins of society, for being the Other. The term Othering describes the reductive action of labelling and defining a person as a subaltern native, as someone who belongs to the socially subordinate category of the Other. The practice of Othering excludes persons who do not fit the norm of the social group, which is a version of the Self; likewise, in human geography, the practice of othering persons means to exclude and displace them from the social group to the margins of society, where mainstream social norms do not apply to them, for being the Other.
  • 3.8K
  • 09 Nov 2022
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
The Physics of Flows in a Curved Channel
Microchannels with curved geometries have been employed for many applications in microfluidic devices in the past decades. The Dean vortices generated in such geometries have been manipulated using different methods to enhance the performance of devices in applications such as mixing, droplet sorting, and particle/cell separation. Understanding the effect of the manipulation method on the Dean vortices in different geometries can provide crucial information to be employed in designing high-efficiency microfluidic devices.
  • 3.8K
  • 25 Dec 2023
Topic Review
The Modulation Recognition Method Based on Deep Learning
Deep learning is a powerful artificial intelligence technology that can learn features from a large amount of data and fit nonlinear networks, so it is widely used in the fields of computer vision, natural language processing, and speech recognition, and has achieved tremendous success. Since mobile communication networks are able to generate large amounts of different types of data at a very fast pace, relevant researchers have applied deep learning to the field of communication, bringing opportunities for the development of communication technologies. For example, signal modulation identification in wireless communication can be done using deep learning techniques, and deep learning-based modulation identification methods have better robustness than traditional AMR methods and higher accuracy rates. There are many excellent neural networks in deep learning, such as convolutional neural network (CNN), recurrent neural network (RNN), etc. Among them, CNN is good at processing image data and RNN is good at processing sequence signals. CNN and RNN are widely used in AMR. The application of these neural networks to deep learning is discussed.
  • 3.8K
  • 08 Oct 2022
Topic Review
Domestic Turkey
The domestic turkey (Meleagris gallopavo domesticus) is a large fowl, one of the two species in the genus Meleagris and the same species as the wild turkey. Although turkey domestication was thought to have occurred in central Mesoamerica at least 2,000 years ago, recent research suggests a possible second domestication event in the southwestern United States between 200 BC and AD 500. However, all of the main domestic turkey varieties today descend from the turkey raised in central Mexico that was subsequently imported into Europe by the Spanish in the 16th century. The domestic turkey is a popular form of poultry, and it is raised throughout temperate parts of the world, partially because industrialized farming has made it very cheap for the amount of meat it produces. Female domestic turkeys are referred to as hens, and the chicks may be called poults or turkeylings. In the United States, the males are referred to as toms, while in the United Kingdom and Ireland, males are stags. The great majority of domestic turkeys are bred to have white feathers because their pin feathers are less visible when the carcass is dressed, although brown or bronze-feathered varieties are also raised. The fleshy protuberance atop the beak is the snood, and the one attached to the underside of the beak is known as a wattle. The English-language name for this species results from an early misidentification of the bird with an unrelated species which was imported to Europe through the country of Turkey. The Latin species name gallopāvō means "chicken peacock".
  • 3.8K
  • 18 Nov 2022
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 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
Thread Protocol
The increasing demand for Internet of Things (IoT) applications has resulted in vast amounts of data, requiring the utilization of big data analytics. The integration of big data analytics in IoT-based smart cities can greatly benefit from the development of wireless communication protocols, among which the Thread protocol has emerged as a promising option. Thread is IEEE 802.15.4 based and has advanced capabilities like mesh networking, IPv6 support, and multiple gateways providing no single point of failure.
  • 3.8K
  • 14 Jul 2023
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
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
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