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Topic Review
Intel MCS-51
The Intel MCS-51 (commonly termed 8051) is a single chip microcontroller (MCU) series developed by Intel in 1980 for use in embedded systems. The architect of the Intel MCS-51 instruction set was John H. Wharton. Intel's original versions were popular in the 1980s and early 1990s and enhanced binary compatible derivatives remain popular today. It is an example of a complex instruction set computer, and has separate memory spaces for program instructions and data. Intel's original MCS-51 family was developed using N-type metal-oxide-semiconductor (NMOS) technology like its predecessor Intel MCS-48, but later versions, identified by a letter C in their name (e.g., 80C51) use complementary metal–oxide–semiconductor (CMOS) technology and consume less power than their NMOS predecessors. This made them more suitable for battery-powered devices. The family was continued in 1996 with the enhanced 8-bit MCS-151 and the 8/16/32-bit MCS-251 family of binary compatible microcontrollers. While Intel no longer manufactures the MCS-51, MCS-151 and MCS-251 family, enhanced binary compatible derivatives made by numerous vendors remain popular today. Some derivatives integrate a digital signal processor (DSP). Beyond these physical devices, several companies also offer MCS-51 derivatives as IP cores for use in field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC) designs.
  • 7.0K
  • 14 Oct 2022
Topic Review
Hazard
A hazard is an agent which has the potential to cause harm to a vulnerable target. The terms "hazard" and "risk" are often used interchangeably. However, in terms of risk assessment, they are two very distinct terms. A hazard is any agent that can cause harm or damage to humans, property, or the environment. Risk is defined as the probability that exposure to a hazard will lead to a negative consequence, or more simply, a hazard poses no risk if there is no exposure to that hazard. Hazards can be dormant or potential, with only a theoretical probability of harm. An event that is caused by interaction with a hazard is called an incident. The likely severity of the undesirable consequences of an incident associated with a hazard, combined with the probability of this occurring, constitute the associated risk. If there is no possibility of a hazard contributing towards an incident, there is no risk. Hazards can be classified as different types in several ways. One of these ways is by specifying the origin of the hazard. One key concept in identifying a hazard is the presence of stored energy that, when released, can cause damage. Stored energy can occur in many forms: chemical, mechanical, thermal, radioactive, electrical, etc. Another class of hazard does not involve release of stored energy, rather it involves the presence of hazardous situations. Examples include confined or limited egress spaces, oxygen-depleted atmospheres, awkward positions, repetitive motions, low-hanging or protruding objects, etc. Hazards may also be classified as natural, anthropogenic, or technological. They may also be classified as health or safety hazards, by the populations that may be affected, and the severity of the associated risk. In most cases a hazard may affect a range of targets, and have little or no effect on others. Identification of hazards assumes that the potential targets are defined, and is the first step in performing a risk assessment.
  • 7.0K
  • 26 Oct 2022
Topic Review
Rolls-Royce Phantom VII
The Rolls-Royce Phantom VII is a full-sized luxury saloon car made by Rolls-Royce Motor Cars. Launched in 2003, it was the first Rolls-Royce developed and introduced after BMW purchased the right to use the Rolls-Royce name and logo in 1998. It is credited with successfully reviving the Rolls-Royce brand and restoring Rolls-Royce's reputation as a maker of luxury cars. The Phantom Drophead Coupé and Phantom Coupé are two-door derivatives of the Phantom launched in 2007 and 2008, respectively. From 2003 until the launch of the smaller Ghost in 2009, the Phantom was the only car produced by Rolls-Royce. The Phantom acted as the company's flagship model, but was less exclusive than all previous Phantoms (none of which surpassed the 600 per year).
  • 7.0K
  • 05 Dec 2022
Topic Review
UAV-based IoT
The Internet of Things (IoT), which consists of a large number of small low-cost devices, has become a leading solution for smart cities, smart agriculture, smart buildings, smart grids, e-healthcare, etc. Integrating unmanned aerial vehicles (UAVs) with IoT can result in an airborne UAV-based IoT (UIoT) system and facilitate various value-added services from sky to ground. In addition to wireless sensors, various kinds of IoT devices are connected in UIoT, making the network more heterogeneous. In a UIoT system, for achieving high throughput in an energy-efficient manner, it is crucial to design an efficient medium access control (MAC) protocol because the MAC layer is responsible for coordinating access among the IoT devices in the shared wireless medium. Thus, various MAC protocols with different objectives have been reported for UIoT.
  • 7.0K
  • 07 Dec 2020
Topic Review
Key Oil Palm Pests and Their Managements
Oil palm, Elaeis guineensis Jacq. (Arecales: Arecaceae), is a multipurpose plantation crop that is extensively grown in the humid tropics across Asia, Africa and the Americas for palm oil and other uses such as sauces, soap, wine, fertilizer (ashes), roofing (leaves), building material (trunk), medicines (roots), and ornamental purposes. Oil palm is attacked by numerous insect species globally, including defoliators, leaf/fruit scrapers, borers and sap feeders. The common oil palm pest management methods include synthetic insecticides, biopesticides, semiochemical lures, cultural practices, and integrated approaches.
  • 7.0K
  • 04 Jan 2023
Topic Review
Propranolol in Post-Traumatic Stress Disorder
Propranolol, a non-cardioselective β1,2 blocker, is most commonly recognised for its application in the therapy of various cardiovascular conditions, such as hypertension, coronary artery disease, and tachyarrhythmias. However, due to its ability to cross the blood–brain barrier and affinity towards multiple macromolecules, not only adrenoreceptors, it has also found application in other fields. For example, it is one of the very few medications successfully applied in the treatment of stage fright. 
  • 7.0K
  • 07 Sep 2022
Topic Review
Synthesis of Fragrances via Cycloaddition or Formal Cycloaddition
Fragrances, short for fragrance ingredients, is a type of compounds with a sweet smell or pleasant odor that has wide applications in the fine chemical industry, especially in perfumes, cosmetics, detergents and food additives. Since the discovery of the Diels–Alder reaction, the cycloaddition of π reactants serves as one of the most powerful methods for the construction of carbocycles, which has a broad application in the fragrance industry.
  • 7.0K
  • 21 Jun 2022
Topic Review
Vishvakarman
Vishvakarman (Sanskrit: विश्वकर्मन्, Viśvakarman; lit. "all creating") is the Personification of ultimate reality and deity of the creative power. He is believed to be one of the ancient architect or engineer who created and taught building of ancient monuments, architectures in Bharat, now India. According to the Rigveda It/He is considered to be the architect, divine engineer of universe from before the advent of time.
  • 7.0K
  • 29 Sep 2022
Topic Review
Aquaporin Inhibitors
Aquaporins (AQPs) are water channel proteins that are essential to life, being expressed in all kingdoms. In humans, there are 13 AQPs, at least one of which is found in every organ system. The structural biology of the AQP family is well-established and many functions for AQPs have been reported in health and disease. AQP expression is linked to numerous pathologies including tumor metastasis, fluid dysregulation, and traumatic injury. The targeted modulation of AQPs therefore presents an opportunity to develop novel treatments for diverse conditions. Various techniques such as video microscopy, light scattering and fluorescence quenching have been used to test putative AQP inhibitors in both AQP-expressing mammalian cells and heterologous expression systems. The inherent variability within these methods has caused discrepancy and many molecules that are inhibitory in one experimental system (such as tetraethylammonium, acetazolamide, and anti-epileptic drugs) have no activity in others. Some heavy metal ions (that would not be suitable for therapeutic use) and the compound, TGN-020, have been shown to inhibit some AQPs. Clinical trials for neuromyelitis optica treatments using anti-AQP4 IgG are in progress. However, these antibodies have no effect on water transport. More research to standardize high-throughput assays is required to identify AQP modulators for which there is an urgent and unmet clinical need.
  • 7.0K
  • 06 Sep 2021
Topic Review
List of Academic Journals by Preprint Policy
This is a list of academic journals by their submission policies regarding the use of preprints prior to publication, such as the arXiv, and bioRxiv. Journals focusing on physics and mathematics are excluded because they routinely accept manuscripts that have been posted to preprint servers. Publishers' policies on self-archiving (including preprint versions) can also be found at SHERPA/RoMEO.
  • 7.0K
  • 29 Dec 2022
Topic Review
Context Collapse
Context collapse refers to the phenomenon in digital communication where distinct social spheres or contexts intersect, leading to challenges in managing audience expectations, privacy boundaries, and self-presentation. It occurs when content intended for one audience becomes visible to multiple, potentially disparate audiences, blurring the boundaries between personal, professional, and social identities online. Context collapse often raises concerns about privacy, authenticity, and social repercussions in digital environments.
  • 7.0K
  • 08 Feb 2024
Topic Review
Acoustic Extinguishing
In the fire-extinguishing process, in principle, one of the components in the fire tetrahedron must be removed. For example, a natural gas fire occurring on a stovetop burner can be extinguished in various ways: Eliminating the fuel source by shutting off the gas supply may be the first option. Another option is to completely cover the flame to block any oxidizer that is present, such as oxygen in the air, during combustion.
  • 7.0K
  • 25 Mar 2022
Topic Review
Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA)
Perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCA) recognize heterogeneous antigens, including myeloperoxidase (MPO), lactoferrin, elastase, cathepsin-G and bactericidal/permeability-increasing protein. Although P-ANCA have diagnostic utility in vasculitides, they may also be found in patients with various other systemic autoimmune rheumatic diseases (SARDs). Nevertheless, the clinical significance and the targets recognized by P-ANCA in such patients remain unclear. For this purpose, herein we investigated the occurrence of ANCA-related antigenic specificities in 82 P-ANCA-positive sera by multiplex ELISA, as well as their association with other autoantibodies. The P-ANCA-positive sera corresponded to patients with vasculitides (n = 24), systemic lupus erythematosus (n = 28), antiphospholipid syndrome (n = 5), Sjögren’s syndrome (n = 7), rheumatoid arthritis (n = 3), systemic scleroderma (n = 1), sarcoidosis (n = 1) and Hashimoto′s thyroiditis (n = 13). In most P-ANCA-positive patients studied (51/82, 62.3%), these autoantibodies occurred in high titers (>1:160). The analysis of P-ANCA-positive sera revealed reactivity to MPO in only 50% of patients with vasculitides, whereas it was infrequent in the other disease groups studied. Reactivity to other P-ANCA-related autoantigens was also rarely detected. Our findings support that high P-ANCA titers occur in SARD. The P-ANCA-positive staining pattern is associated with MPO specificity in vasculitides, while in other autoimmune diseases, it mostly involves unknown autoantigens. 
  • 7.0K
  • 27 Aug 2021
Topic Review
Antiparasitic Mebendazole for the Treatment of Brain Cancers
Cancer ranks as a leading cause of death and a significant barrier to increasing life expectancy in every country. According to estimates from the World Health Organization (WHO) in 2019, cancer is the first or second leading cause of death before age 70 in 112 of 183 countries and ranks third or fourth in 23 countries. Tumor treatments usually consist of chemotherapy, radiotherapy, surgery, targeted therapy, immunotherapy, and endocrine therapy that can be used individually or in combination, depending on the stage and type of tumor and diagnosis. Several factors reduce the practical improvement of a cancer patient’s prognosis. Drug-untreatable targets, chemoresistance, tumor heterogeneity, and metastases formation are significant barriers to the effective cure of cancer patients. Despite intense preclinical and clinical research efforts, the survival rate of patients suffering from the most aggressive cancer types has not yet improved, mainly due to therapeutic failure. Moreover, nearly all anticancer medications on the market have serious adverse effects; therefore, new, safer anticancer drugs are desirable.
  • 7.0K
  • 19 Jan 2023
Topic Review
Hungarian Soviet Republic
The Hungarian Soviet Republic, literally the Republic of Councils in Hungary (Hungarian: Magyarországi Tanácsköztársaság), also known as the Hungarian Socialist Federative Soviet Republic (Hungarian: Magyarországi Szocialista Szövetséges Tanácsköztársaság) was a short-lived (133 days) communist rump state. When the Republic of Councils in Hungary was established in 1919, it controlled approximately 23% of the territory of Hungary's classic pre-World War I territories (325 411 km2). It was the successor of the first Hungarian People's Republic and lasted from only 21 March to 1 August 1919. Though the de jure leader of the Hungarian Soviet Republic was president Sándor Garbai, the de facto power was in the hands of foreign minister Béla Kun, who maintained direct contact with Lenin via radiotelegraph. It was Lenin who gave the direct orders and advice to Béla Kun via constant radio communication with the Kremlin. It was the second socialist state in the world to be formed, preceded by only the October Revolution in Russia which brought the Bolsheviks to power. The Hungarian Republic of Councils had military conflicts with the Kingdom of Romania, the Kingdom of Serbs, Croats and Slovenes and the evolving Czechoslovakia. It ended on 1 August 1919 when Hungarians sent representatives to negotiate their surrender to the Romanian forces. Due to the mistranslation, it is often referred to as "Hungarian Soviet republic" in English sources, despite the literal name "Republic of Councils in Hungary" was chosen for the purpose to avoid any strong ethnic connotation with Hungarian people, and express the Proletarian internationalist doctrine of the new Communist regime.
  • 7.0K
  • 20 Oct 2022
Topic Review
Human Genetic Clustering
Human genetic clustering is the degree to which human genetic variation can be partitioned into a small number of groups or clusters. A leading method of analysis uses mathematical cluster analysis of the degree of similarity of genetic data between individuals and groups in order to infer population structures and assign individuals to hypothesized ancestral groups. A similar analysis can be done using principal component analysis, and several recent studies deploy both methods. Analysis of genetic clustering examines the degree to which regional groups differ genetically, the categorization of individuals into clusters, and what can be learned about human ancestry from this data. There is broad scientific agreement that a relatively small fraction of human genetic variation occurs between populations, continents, or clusters. Researchers of genetic clustering differ, however, on whether genetic variation is principally clinal or whether clusters inferred mathematically are important and scientifically useful.
  • 7.0K
  • 23 Nov 2022
Topic Review Peer Reviewed
High-Speed Railway
Union Internationale des Chemins (UIC) defines the high-speed railway (HSR) as a high-speed railway system that contains the infrastructure and the rolling stock. The infrastructure can be newly built dedicated lines enabled for trains to travel with speed above 250 km/h or upgraded conventional lines with a speed up to 200 or even 220 km/h. HSR requires specially built trains with increased power to weight ratio and must have an in-cab signalling system as traditional signalling systems are incapable of above 200 km/h.
  • 7.0K
  • 18 Apr 2022
Topic Review
Microalgae/Cyanobacteria in Biodegradation of Plastics
Cyanobacteria (e.g., Synechocystis sp. PCC 6803, and Synechococcus elongatus PCC 7942), which are photosynthetic prokaryotes and were previously identified as blue-green algae, are currently under close attention for their abilities to capture solar energy and the greenhouse gas carbon dioxide for the production of high-value products. In the last few decades, these microorganisms have been exploited for different purposes (e.g., biofuels, antioxidants, fertilizers, and ‘superfood’ production). Microalgae (e.g., Chlamydomonas reinhardtii, and Phaeodactylum tricornutum) are also suitable for environmental and biotechnological applications based on the exploitation of solar light. In recent years, several studies have been targeting the utilization of microorganisms for plastic bioremediation. Among the different phyla, the employment of wild-type or engineered cyanobacteria may represent an interesting, environmentally friendly, and sustainable option (e.g., mismanaged plastics as source of carbons for their cultivation: the connection between their simultaneous utilization for biofuels or chemicals production and microplastics consumption on the surface of basins).
  • 7.0K
  • 05 Jan 2021
Topic Review
Contact Lens Materials - A Materials Science Perspective
Contact lens materials are typically based on polymer- or silicone-hydrogel, with additional manufacturing technologies employed to produce the final lens. These processes are simply not enough to meet the increasing demands from CLs and the ever-increasing number of contact lens (CL) users. New materials and engineering offer increasing functionality or improved properties over previous generations.
  • 7.0K
  • 27 Jan 2022
Topic Review
Revolutions of 1848
The Revolutions of 1848, known in some countries as the Springtime of the Peoples or the Springtime of Nations, were a series of political upheavals throughout Europe in 1848. It remains the most widespread revolutionary wave in European history. The revolutions were essentially democratic and liberal in nature, with the aim of removing the old monarchical structures and creating independent nation-states. The revolutions spread across Europe after an initial revolution began in France in February. Over 50 countries were affected, but with no significant coordination or cooperation among their respective revolutionaries. Some of the major contributing factors were widespread dissatisfaction with political leadership, demands for more participation in government and democracy, demands for freedom of the press, other demands made by the working class, the upsurge of nationalism, the regrouping of established government forces, and the European Potato Failure, which triggered mass starvation, migration, and civil unrest. The uprisings were led by temporary coalitions of reformers, the middle classes ("the bourgeoisie") and workers. However, the coalitions did not hold together for long. Many of the revolutions were quickly suppressed; tens of thousands of people were killed, and many more were forced into exile. Significant lasting reforms included the abolition of serfdom in Austria and Hungary, the end of absolute monarchy in Denmark, and the introduction of representative democracy in the Netherlands. The revolutions were most important in France, the Netherlands, Italy, the Austrian Empire, and the states of the German Confederation that would make up the German Empire in the late 19th and early 20th century.
  • 6.9K
  • 05 Dec 2022
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