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Adverse Health Effects from Lunar Dust Exposure
The respirable fraction of lunar dusts may be toxic to humans. NASA has therefore determined that an exposure standard is necessary to limit the amount of respirable airborne lunar dusts to which astronauts will be exposed. The nominal toxicity that is expected from ordinary mineral dust may be increased for lunar dusts due to the large and chemically reactive surfaces of the dust grains. Human exposures to mineral dusts during industrial operations and from volcanic eruptions give researchers some sense of the relative toxicity of lunar dust, although the Earth-based analogs have serious limitations. Animal and cellular studies provide further evidence that mineral dusts can be somewhat toxic. Earth-based research of mineral dust has shown that freshly fractured surfaces are chemically reactive and can elicit an increased toxic response. Since lunar dust is formed in space vacuum from highly energetic processes, the grain surfaces can be expected to be indefinitely reactive on the lunar surface. NASA predicts that this chemical reactivity will change once the dust is brought into a habitable environment. Dust from lunar soil that was carried into spacecraft during the Apollo missions proved to be a nuisance. The lack of gravity, or the existence of microgravity, increases the time during which dust remains airborne, thereby increasing the probability that these dust particles will be inhaled. Lunar dust particles that are generated by impaction in a deep vacuum have complex shapes and highly reactive surfaces that are coated with a thin layer of vapor-deposited mineral phase. Airborne mineral dust in a variety of forms has been shown to present a serious health hazard to ground-based workers. Crew members who will be at a lunar outpost can be directly exposed to lunar dust in several ways. After crew members perform spacewalks or EVAs, they will introduce into the habitat a large quantity of dust that will have collected on spacesuits and boots. Cleaning of the suits between EVAs and changing of the Environmental Control Life Support System (ECLSS) filters are other operations that could result in direct exposure to lunar dusts. In addition, if the final spacesuit design is based on the current spacesuit design, EVAs may cause dermal injuries, and the introduction of lunar dusts into the suits' interior, which may enhance skin abrasions. When the crew leaves the lunar surface and returns to microgravity, the dust that is introduced into the crew return vehicle will "float," thus increasing the opportunity for ocular and respiratory injury.
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Topic Review
WannaCry Ransomware Attack
The WannaCry ransomware attack was a worldwide cyberattack in May 2017 by the WannaCry ransomware cryptoworm, which targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the Bitcoin cryptocurrency. It propagated through EternalBlue, an exploit developed by the United States National Security Agency (NSA) for older Windows systems. EternalBlue was stolen and leaked by a group called The Shadow Brokers a month prior to the attack. While Microsoft had released patches previously to close the exploit, much of WannaCry's spread was from organizations that had not applied these, or were using older Windows systems that were past their end-of-life. These patches were imperative to organizations' cyber security but many were not implemented due to ignorance of their importance. Some have claimed a need for 24/7 operation, aversion to risking having formerly working applications breaking because of patch changes, lack of personnel or time to install them, or other reasons. The attack began at 07:44 UTC on 12 May 2017 and was halted a few hours later at 15:03 UTC by the registration of a kill switch discovered by Marcus Hutchins. The kill switch prevented already infected computers from being encrypted or further spreading WannaCry. The attack was estimated to have affected more than 200,000 computers across 150 countries, with total damages ranging from hundreds of millions to billions of United States dollar . Security experts believed from preliminary evaluation of the worm that the attack originated from North Korea or agencies working for the country. In December 2017, the United States and United Kingdom formally asserted that North Korea was behind the attack. A new variant of WannaCry forced Taiwan Semiconductor Manufacturing Company (TSMC) to temporarily shut down several of its chip-fabrication factories in August 2018. The virus spread to 10,000 machines in TSMC's most advanced facilities.
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Topic Review
Philosophy of Technology
The philosophy of technology is a sub-field of philosophy that studies the nature of technology and its social effects. Philosophical discussion of questions relating to technology (or its Greek ancestor techne) dates back to the very dawn of Western philosophy. The phrase "philosophy of technology" was first used in the late 19th century by German-born philosopher and geographer Ernst Kapp, who published a book titled Elements of a Philosophy of Technology (German title: Grundlinien einer Philosophie der Technik).
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Topic Review
Distributed Ledger Technology Law
Distributed ledger technology law ("DLT law") (also called Blockchain law,, Lex Cryptographia or Algorithmic legal order ) is not yet defined and recognized but an emerging field of law due to the recent dissemination of distributed ledger technology application in business and governance environment.
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Topic Review
Evolution of Dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 243-233 Ma (million years ago) from the Anisian to the Carnian ages, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present in 98% of bootstraps. It is diagnosed by many features including loss of the postfrontal on the skull and an elongate deltopectoral crest on the humerus. In March 2017, scientists reported a new way of classifying the dinosaur family tree, based on newer and more evidence than available earlier. According to the new classification, the original dinosaurs, arising 200 million years ago, were small, two-footed omnivorous animals with large grasping hands. Descendants (for the non-avian dinosaurs) lasted until 66 million years ago.
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  • 14 Oct 2022
Topic Review
Al-Shifa Pharmaceutical Factory
The Al-Shifa (الشفاء, Arabic for "healing") pharmaceutical factory in Khartoum North, Sudan, was constructed between 1992 and 1996 with components imported from Germany , India , Italy, Sweden, Switzerland , Thailand and the United States . It was opened on 12 July 1997 and bombed by the United States on 20 August 1998. The industrial complex was composed of four buildings. It was the largest pharmaceutical factory in Khartoum and employed over 300 workers, producing medicine both for human and veterinary use. The factory was destroyed in 1998 by a missile attack launched by the United States government, killing one employee and wounding eleven. The U.S. government claimed that the factory was used for the processing of VX nerve agent and that the owners of the plant had ties to the terrorist group al-Qaeda. These justifications for the bombing were disputed by the owners of the plant, the Sudanese government, and other governments. American officials later acknowledged "that the evidence that prompted President Clinton to order the missile strike on the Shifa plant was not as solid as first portrayed. Indeed, officials later said that there was no proof that the plant had been manufacturing or storing nerve gas, as initially suspected by the Americans, or had been linked to Osama bin Laden, who was a resident of Khartoum in the 1980s." The attack took place a week after the Monica Lewinsky scandal and two months after release of the film Wag the Dog, prompting some commentators to describe the attack as a distraction for the public from the scandal.
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Topic Review
Chinese Information Operations and Information Warfare
Informatized warfare of China is the implementation of information warfare (IW) within the Chinese military. Laid out in the Chinese Defence White Paper of 2008, informatized warfare includes the utilization of information-based weapons and forces, including battlefield management systems, precision-strike capabilities, and technology-assisted command and control (C4ISR). However, some media and analyst report also uses the term to describe the political and espionage effort from the Chinese state.
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  • 14 Oct 2022
Topic Review
Dref Friction Spinning
Friction Spinning or Dref Spinning is a textile technology that suitable for spinning coarse counts of yarns and technical core-wrapped yarns. Dref yarns are bulky, with low tensile strength making them suitable for blankets and mop yarns, they can be spun from asbestos, carbon fibres and make filters was water systems.[clarification needed] Yarns such as Rayon and Kevlar can be spun using this method. The technology was developed around 1975 by Dr. Ernst Fehrer.
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Topic Review
Alpha-Amanitin
alpha-Amanitin or α-amanitin is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the mushroom genus Amanita, one being the death cap (Amanita phalloides) as well as the destroying angel, a complex of similar species, principally A. virosa and A. bisporigera. It is also found in the mushrooms Galerina marginata and Conocybe filaris. The oral -1">50 of amanitin is 100 μg/kg for rats. Unlike most cyclic peptides, amatoxins (and phallotoxins) are synthesized on ribosomes. The genes encoding the proprotein for α-amanitin belong to the same family as those that encode for phallacidin (a phallotoxin).
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Topic Review
Addax
The addax (Addax nasomaculatus), also known as the white antelope and the screwhorn antelope, is an antelope native to the Sahara Desert. The only member of the genus Addax, it was first described scientifically by Henri de Blainville in 1816. As suggested by its alternative name, the pale antelope has long, twisted horns - typically 55 to 80 cm (22 to 31 in) in females and 70 to 85 cm (28 to 33 in) in males. Males stand from 105 to 115 cm (41 to 45 in) at the shoulder, with females at 95 to 110 cm (37 to 43 in). They are sexually dimorphic, as the females are smaller than the males. The colour of the coat depends on the season - in the winter, it is greyish-brown with white hindquarters and legs, and long, brown hair on the head, neck, and shoulders; in the summer, the coat turns almost completely white or sandy blonde. The addax mainly eats grasses and leaves of any available shrubs, leguminous herbs and bushes. They are well-adapted to exist in their desert habitat, as they can live without water for long periods of time. Addax form herds of five to 20 members, consisting of both males and females. They are led by the oldest female. Due to its slow movements, the addax is an easy target for its predators: humans, lions, leopards, cheetahs and African wild dogs. Breeding season is at its peak during winter and early spring. The natural habitat of the addax are arid regions, semideserts and sandy and stony deserts. The addax is a critically endangered species of antelope, as classified by the IUCN. Although extremely rare in its native habitat due to unregulated hunting, it is quite common in captivity. The addax was once abundant in North Africa; however it is currently only native to Chad, Mauritania, and Niger. It is extirpated from Algeria, Egypt, Libya, Sudan, and Western Sahara, but has been reintroduced into Morocco and Tunisia.
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