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Topic Review
Gastric Cancer Classification
Gastric cancer(GC) is the fourth most common cause of cancer-related mortalities worldwide. The incidence rate of GC rises progressively with age, the median age at diagnosis is 70 years. GC is a multifactorial disease, and both environmental and genetic factors have a role in its aetiology. Regarding the age of diagnosis, it is divided into early-onset gastric carcinoma (EOGC; 45 years or younger) and conventional GC (CGC; older than 45). EOGC relies mostly on genetic factors and therefore provides a unique model to study genetic alterations in GCs.
  • 5.0K
  • 27 Oct 2020
Topic Review
Pathophysiology of Osteoporosis
Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss.
  • 5.0K
  • 15 Nov 2022
Topic Review
Spider Silk with Inorganic Nanomaterials
High-performance functional biomaterials are becoming increasingly requested. Numerous natural and artificial polymers have already demonstrated their ability to serve as a basis for bio-composites. Spider silk offers a unique combination of desirable aspects such as biocompatibility, extraordinary mechanical properties, and tunable biodegradability, which are superior to those of most natural and engineered materials. Modifying spider silk with various inorganic nanomaterials with specific properties has led to the development of the hybrid materials with improved functionality. The purpose of using these inorganic nanomaterials is primarily due to their chemical nature, enhanced by large surface areas and quantum size phenomena. Functional properties of nanoparticles can be implemented to macro-scale components to produce silk-based hybrid materials, while spider silk fibers can serve as a matrix to combine the benefits of the functional components. Therefore, it is not surprising that hybrid materials based on spider silk and inorganic nanomaterials are considered extremely promising for potentially attractive applications in various fields, from optics and photonics to tissue regeneration. This review summarizes and discusses evidence of the use of various kinds of inorganic compounds in spider silk modification intended for a multitude of applications. It also provides an insight into approaches for obtaining hybrid silk-based materials via 3D printing.
  • 5.0K
  • 29 Sep 2020
Topic Review
List of DOS Commands
This article presents a list of commands used by DOS operating systems, especially as used on x86-based IBM PC compatibles (PCs). Other DOS operating systems are not part of the scope of this list. In DOS, many standard system commands were provided for common tasks such as listing files on a disk or moving files. Some commands were built into the command interpreter, others existed as external commands on disk. Over the several generations of DOS, commands were added for the additional functions of the operating system. In the current Microsoft Windows operating system, a text-mode command prompt window, cmd.exe, can still be used.
  • 5.0K
  • 14 Oct 2022
Topic Review Peer Reviewed
Characteristics, Impacts and Trends of Urban Transportation
Economic growth, urban development and the prosperity of the automobile industry have driven a huge shift in global urban transportation from walking to public transportation and then to automobiles. Private mobility has become an important part of residents’ daily trips. Cities, especially automobile-dependent cities, face a variety of negative impacts such as increased commuting distances, higher congestion costs, traffic accidents, traffic pollution including climate change, etc. Therefore, how to balance the relationship between people’s growing demand for private motorization with the development of urbanization, modernization and motorization and the huge economic, social and environmental costs brought about by them, so as to realize the sustainable development of cities and transportation, is the main problem facing cities around the world. The entry focuses on trends in the sustainable development of urban transportation such as restrictions in private car ownership and use, electrification of urban transportation, intelligent transportation systems (including shared mobility, customized buses and Mobility as a Service/MaaS) and transit-oriented development (TOD). China, as the largest global automobile producer and consumer, represents and leads the growth and evolution of other emerging countries.
  • 5.0K
  • 15 Jun 2022
Topic Review
Meta-Intelligence
The concept of meta-intelligence is as a way of understanding the relations of control and coordination among creative, analytical, practical, and wisdom-based approaches to problem solving (Sternberg n.d.b). An approach involves a complex of intellectual skills and attitudes applied to one or more problems.
  • 5.0K
  • 11 May 2021
Topic Review
Strain
In chemistry, a molecule experiences strain when its chemical structure undergoes some stress which raises its internal energy in comparison to a strain-free reference compound. The internal energy of a molecule consists of all the energy stored within it. A strained molecule has an additional amount of internal energy which an unstrained molecule does not. This extra internal energy, or strain energy, can be likened to a compressed spring. Much like a compressed spring must be held in place to prevent release of its potential energy, a molecule can be held in an energetically unfavorable conformation by the bonds within that molecule. Without the bonds holding the conformation in place, the strain energy would be released.
  • 5.0K
  • 04 Nov 2022
Topic Review
Probabilistic Slope Stability Evaluation
Evaluating the stability of slopes in soil is an important, interesting, and challenging aspect of civil engineering. Despite the advances that have been made, evaluating the stability of slopes remains a challenge. Slope failures are often caused by processes that increase shear stresses or decrease shear strengths of the soil mass [4, 9]. Water plays a role in many of the processes that reduce strength; water is also involved in many types of loads on slopes that increase shear stresses. Another factor involved in most slope failures is the presence of soils that contain clay minerals. In concept, any slope with a factor of safety above 1.0 should be stable [6, 10]. In practice, however, the level of stability is seldom considered acceptable unless the factor of safety is significantly greater than 1.0. In this study an attempt has been done to perform stability analyses corresponding to several different conditions, reflecting different stages in the life of the new railway embankment found in Ethiopia. As various parameters are involved and determined based on correlations, the probabilistic approach was employed to scrutinize the effects of uncertainty on the likelihood of failure. There is no problem with performing a single analysis in which the embankment is considered to be drained and is treated in terms of effective stresses, and in which the clay foundation material is considered to be undrained and is treated in terms of total stresses (during end-of-construction analysis). This is because equilibrium in terms of total stresses must be satisfied for both total and effective stress analyses [2]. The inertia slope stability analysis was used. Since the foundation materials are overconsolidated cohesive soils such as stiff to very stiff clays that tend to dilate during the seismic shaking. The embankment is also expected to be well graded compacted granular material [12]. The critical factor of safety for the railway embankment during short term analysis was found to be 2.199. However, it has increased by 17.6% during the long term analysis (i.e., 2.585). Typical minimum factor of safety used in slope design are about 1.5 for normal long-term loading conditions and about 1.3 for end-of- construction conditions.  Apart from that, the minimum short term and long term factor of safety were reduced by 44.5% and 35.9% respectively, due to the introduction of the horizontal seismic load in the limit equilibrium analysis. According to Hynes-Griffin and Franklin (1984) criteria [8] the minimum factor of safety for ~1m tolerable displacement is 1. However, the minimum factor of safety during the pseudostatic analysis (i.e., 1.221) was found to be 22% higher than the required minimum factor of safety. Beside, Newmark’s deformation analysis has been done to predict slope displacement. However, the analysis predicted zero permanent slope displacement. Since; the Newmark (1965) method assumes no deformation of the slope during the earthquake if the pseudostatic factor of safety is greater than 1.0. The more realistic probability of failure is likely in between of 0% and 6.9 %. The sensitivity analysis showed that, the cohesion of the clay layer (i.e., layer II) governs the stability of the railway embankment.
  • 5.0K
  • 30 Oct 2020
Topic Review
Wake
In fluid dynamics, a wake may either be: 1. the region of recirculating flow immediately behind a moving or stationary blunt body, caused by viscosity, which may be accompanied by flow separation and turbulence, or 2. the wave pattern on the water surface downstream of an object in a flow, or produced by a moving object (e.g. a ship), caused by density differences of the fluids above and below the free surface and gravity (or surface tension).
  • 5.0K
  • 08 Nov 2022
Topic Review
Ecolinguistics
Ecolinguistics, or ecological linguistics, emerged in the 1990s as a new paradigm of linguistic research, widening sociolinguistics to take into account not only the social context in which language is embedded, but also the ecological context of the living systems and physical enviornment that life depends on. Michael Halliday's 1990 paper New ways of Meaning: the challenge to applied linguistics is often credited as a seminal work which provided the stimulus for linguists to consider the ecological context and consequences of language. Among other things, the challenge that Halliday put forward was to make linguistics relevant to overarching contemporary issues, particularly the widespread destruction of the ecosystems that life depends on. The main example Halliday gave was that of 'economic growth', describing how 'countless texts repeated daily all around the world contain a simple message: growth is good. Many is better than few, more is better than less, big is better than small, grow is better than shrink', which leads to ecologically destructive consequences.
  • 5.0K
  • 21 Nov 2022
Topic Review
Drone Detection and Defense Systems
Drones are small and low-cost unmanned aerial vehicles (UAVs). With the decrease in the cost and size of drones in recent years, their number has also increased exponentially. As such, the concerns regarding security aspects that are raised by their presence are also becoming more serious.
  • 5.0K
  • 10 Mar 2022
Topic Review
Desalination in Mexico
Since the sixteenth century, water desalination systems have been developed. Mexico is a country that faces a severe water shortage, mainly due to its territorial extension, because the concentration of water resources is located in the southern zone of the country, while the main industrial activity is carried out in the north (which presents scarcity conditions). The distance and the technical limitations of transporting water between the northern and southern zones make water desalination the main tool to combat water stress in Mexico.
  • 5.0K
  • 16 Nov 2022
Topic Review
Electrocardiogram Sensor
It is well-known that cardiovascular disease is one of the major causes of death worldwide nowadays. Electrocardiogram (ECG) sensor is one of the tools commonly used by cardiologists to diagnose and detect signs of heart disease with their patients. Since fast, prompt and accurate interpretation and decision is important in saving the life of patients from sudden heart attack or cardiac arrest, many innovations have been made to ECG sensors. However, the use of traditional ECG sensors is still prevalent in the clinical settings of many medical institutions.
  • 5.0K
  • 10 Feb 2021
Topic Review
North–South Commuter Railway
The North–South Commuter Railway (NSCR), also known as the Clark–Calamba Railway, is a 148 km (92 mi) urban rail transit line being constructed in Luzon. It will run from New Clark City in Capas, Tarlac to Calamba, Laguna with 36 stations, with historic stations to be restored. Originally planned in the 1990s, the project has been repetitively halted after disagreements on funding and allegations of overpricing. The first proposal was the 32 km (20 mi) "Manila–Clark rapid railway" with Spain, and during the 2000s, the NorthRail project with China that was discontinued in 2011. The present line is under the Duterte administration and is to be aided with Japanese financing. It was initially reported to have a total length of 180 km (110 mi), though it was reduced to 148 kilometers (92 mi) after a segment to Los Baños was scrapped. The railway system is expected to cost ₱777.55 billion (US$14.95 billion), making it one of the most expensive projects of the Build! Build! Build! Infrastructure Program. Partial operations will begin by 2021, and full operations is expected to begin by 2025. The NSCR will comprise two sections corresponding to the Philippine National Railways' old main lines; the 91 km (57 mi) fully-elevated NSCR North which is being built over the mostly-defunct North Main Line in northern Metro Manila and Central Luzon, and the 56 km (35 mi) NSCR South which will use the existing PNR Metro Commuter Line infrastructure between Tutuban and Calamba, which were historically parts of the South Main Line and will have elevated, at-grade and depressed sections. The project's construction is divided into three phases with the NSCR North being separated between the 38 km (24 mi) NSCR North 1 commuter line between Tutuban and Malolos, and the 53 kilometres (33 mi) NSCR North 2 regional line from Malolos to New Clark City. It will also be linked to existing and future railway lines such as Line 8, Line 9, the Calamba–Bicol South Main Line and Calamba–Batangas City Railway.
  • 5.0K
  • 09 Oct 2022
Topic Review
Digital Image Correlation
Digital Image Correlation (DIC) is a non-invasive imaging technique that has been used in a significant number of research fields to measure the strain fields across the surface of a body. This entry gives a basic overview of how the DIC method came to be, both in two and three dimensions and some information about the more recent development of DIC in the X-ray spectrum. 
  • 5.0K
  • 29 Oct 2020
Topic Review
China Lake Grenade Launcher
The China Lake Model (or China Lake pump-action grenade launcher) is a pump-action grenade launcher that was developed by the Special Projects Division of the Naval Air Weapons Station (NAWS), which provided equipment to United States Navy SEALs.
  • 5.0K
  • 18 Nov 2022
Topic Review
Swisscom
Swisscom AG is a major telecommunications provider in Switzerland. Its headquarters are located at Worblaufen near Bern. The Switzerland owns 51.0 percent of Swisscom AG. According to its own published data, Swisscom holds a market share of 60% for mobile, 67% for broadband and 33% for TV telecommunication in Switzerland. Its Italian subsidiary Fastweb is attributed 16% of private clients and 29% of corporate clients share of Italian broadband and is also active in the mobile market. The Swiss telegraph network was first set up in 1852, followed by telephones in 1877. The two networks were combined with the postal service in 1920 to form the PTT (Postal Telegraph and Telephone). It struggled to develop a homegrown digital network, with the first digital exchange launched in 1986, but pioneered the NATEL A mobile service in 1978 and the GSM-based NATEL D offering a digital service in 1993. The Swiss telecommunications market was deregulated in 1997. Telecom PTT was spun off and rebranded Swisscom ahead of a partial privatisation in 1997 which has left the Swiss government with a 51% stake. Besides pioneering the first mobile telephone network NATEL A, the present-day Swisscom owns the protected brand NATEL, which is used and known only in Switzerland . 25% of Swisscom Mobile was sold to Vodafone in 2001. Since then, Swisscom has bought a majority stake in Italy's second-biggest telecom company Fastweb and invested in areas such as hospitality support, cloud services, mobile solutions and billing.
  • 5.0K
  • 29 Nov 2022
Topic Review
Epoxide Synthesis and Ring-Opening Reactions
This entry concentrates on some examples of success stories from the synthesis of approved medicines and drug candidates using epoxide chemistry in the development of robust and efficient syntheses at large scale. The focus is on those parts of each synthesis related to the substrate-controlled/diastereoselective and catalytic asymmetric synthesis of epoxide intermediates and their subsequent ring-opening reactions with various nucleophiles. These are described in the form of case studies of high profile pharmaceuticals spanning a diverse range of indications and molecular scaffolds such as heterocycles, terpenes, steroids, peptidomimetics, alkaloids and main stream small molecules. Representative examples include, but are not limited to the antihypertensive diltiazem, the antidepressant reboxetine, the HIV protease inhibitors atazanavir and indinavir, efinaconazole and related triazole antifungals, tasimelteon for sleep disorders, the anticancer agent carfilzomib, the anticoagulant rivaroxaban the antibiotic linezolid and the antiviral oseltamivir. Emphasis is given on aspects of catalytic asymmetric epoxidation employing metals with chiral ligands particularly with the Sharpless and Jacobsen–Katsuki methods as well as organocatalysts such as the chiral ketones of Shi and Yang, Pages's chiral iminium salts and typical chiral phase transfer agents.
  • 5.0K
  • 09 Oct 2020
Topic Review
Submarine Cables Radial Water Barrier
The submarine cables manufacturing industry is growing very rapidly. Solutions used so far, usually adapted from designs of land cables, do not fulfil the new, more demanding requirements. The phenomenon of water ingress into insulation and its absorption are basic factors determining the service life of submarine cables. The radial water barrier is the only effective component of cable design that may guarantee the required minimum 30-year longevity of submarine cables.
  • 5.0K
  • 01 Jun 2021
Topic Review
South Korean Transitional Periods from Imitation to Innovation
The technology transfer and development model of South Korea is unique. After other countries refused to license and transfer modern technologies to this country, Korea resorted to its national research system to add innovative content to its imitative products. 
  • 5.0K
  • 23 Mar 2022
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