Tuesday, 18 June 2019

Magnitude 5.8 Earthquake in Sichaun Province China kills at least 12 people.

The United States Geological Survey recorded a Magnitude 5.8 Earthquake at a depth of 10 km, in Changning County in Sichaun Province, China, at about 10.55 pm local time (about 2.55 pm GMT) on Monday 17 June 2019. The quake is reported to have several buildings to have collapsed in Changning and Qixian counties, as well as some damage in Xuyong County. A total of twelve people have been reported dead so far, eight in Changning and four in Qixian, with 134 reports of injuries, and the number of both dead and injured is expected to rise as search teams work their way through the debris. The area has been hit by a number of large aftershocks.

Rescue workers on a collapsed building in Changning County, Sichuan, following an Earthquake on 17 June 2019. Reuters.

Much of western China and neighbouring areas of Central Asia and the Himalayas, are prone to Earthquakes caused by the impact of the Indian Plate into Eurasia from the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. When two tectonic plates collide in this way and one or both are oceanic then one will be subducted beneath the other (if one of the plates is continental then the other will be subducted), but if both plates are continental then subduction will not fully occur, but instead the plates will crumple, leading to folding and uplift (and quite a lot of Earthquakes). The collision of the Indian and Eurasian plates has lead to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

 The movement of India into Eurasia over the last 71 million years. USGS.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.
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Monday, 17 June 2019

Acidaminococcus provencensis: A new species of Firmicute Bacteria.

Firmicutes are a group of Bacteria which are not typically pathogenic, but which includes a few species such as Staphylococcus aureus and Listeria monocytogenes which can cause food poisoning or skin infections, as well as more dangerous species such as Clostridium perfringens (Gas Gangrene) and Bacillus anthracis (Anthrax) which are normally soil-dwelling Bacteria, but which can cause lethal infections due to the toxins which they produce. Members of the genus Acidaminococcus are anaerobic Bacteria (Bacteria which do not require oxygen) which are able to obtain energy solely from the breakdown of amino acids. Members of this genus have been found living in the guts of Humans and Pigs, with high levels associated with stunted growth in Human children.

In a paper published in the journal New Microbes and New Infections on 14 June 2019, Tatsuki Takakura of the Analytical & Medical Solution Business Group at the Hitachi High-Technologies Corporation and the Institut Hospitalo-Universitaire Méditerranée-Infection in Marseille, Hussein Anani of Microbes Evolution Phylogeny and Infections at Aix-Marseille Université, Amaël Fadlane and Anthony Fontanini, also of the Institut Hospitalo-Universitaire Méditerranée-Infection, Didier Raoult, again of the Institut Hospitalo-Universitaire Méditerranée-Infection and of Microbes Evolution Phylogeny and Infections at Aix-Marseille Université, and Jacques Yaacoub Bou Khalil, once again of the Institut Hospitalo-Universitaire Méditerranée-Infection, describe a new species of Acidaminococcus isolated from a Human stool sample collected at the Hospital de la Timone in Marseille as part of a random screening program.

The new species is named Acidaminococcus provencensis, meaning 'from Provence'. When cultured in Colombia agar enriched with 5% sheep’s blood in strict anaerobic conditions at 37°C, it formed circular colonies of white, cocci-shaped (spherical) Bacterial cells with an average mean diameter of 0.8 μm. These cells were identified as belonging to a new species of Acidaminococcus by 16S rRNA gene sequencing.

Scanning electron micrograph of colony of Acidaminococcus provencensis. Takakura et al. (2019).

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Sunday, 16 June 2019

Heliotropium pakistanicum: A new species of Heliotrope from Pakistan.

Heliotropes, Heliotropium, are herbaceous plants in the Borage Family, Boraginaceae, found in tropical, subtropical and temperate regions around the world. The genus is extremely specious, with over 300 described species. The name Heliotrope means 'Sun turn', from the belief that these plants turned their flowers to follow the Sun, though they do not actually do this. Heliotropes are cultivated as ornamental garden plants, and sometimes to produce dyes from their purple flowers, but they are not considered edible and some species are toxic to livestock.

In a paper published in the journal Planta Daninha on 13 June 2019, Humaira Shaheen of COMSATS University Islamabad, Daniel Potter of the University of California, Davis, and Mirza Faisal Qaseem and Rahmatullah Qureshi of the Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, describe a new species of Heliotrope from the Thal Desert of Punjab Province, Pakistan.

The new species is named Heliotropium pakistanicum, in reference to the country where it was found. It is a succulent herbaceous plant reaching about 60 cm in height, with fleshy stems growing from a woody base. 6-15 small yellow and green flowers are produced in April. The species appears to be endemic to the Thal Desert (i.e. not be found anywhere else).

Heliotropium pakistanicum. Shaheen et al. (2019).

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Saturday, 15 June 2019

Asteroid 2011 TC4 passes the Earth.

Asteroid 2011 TC4 passed by the Earth at a distance of about 12 732 000 km (33.1 times the average  distance between the Earth and the Moon, or 8.51% of the distance between the Earth and the Sun), slightly after midnight GMT on Wednesday 12 June 2019. There was no danger of the asteroid hitting us, though were it to do so it would have presented a significant threat. 2011 TC4 has an estimated equivalent diameter of 160-520 m (i.e. it is estimated that a spherical object with the same volume would be 180-570 m in diameter), and an object of this size would be predicted to be capable of passing through the Earth's atmosphere relatively intact, impacting the ground directly with an explosion that would be between about 6000 and 470 000 times as powerful as the Hiroshima bomb. Such an impact would result in an impact crater between 2.5 and 8 km in diameter and devastation on a global scale, as well as climatic effects that would last decades or even centuries.

The calculated orbit of 2018 XG5. JPL Small Body Database.

2011 TC4 was discovered on 3 October 2011 by the University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount Lemmon in the Catalina Mountains north of Tucson. The designation 2011 TC1 implies that the asteroid was the 27th object (asteroid C1 - in numbering asteroids the letters A-Y, excluding I, are assigned numbers from 1 to 24, with a number added to the end each time the alphabet is ended, so that A = 1, A1 = 25, A2 = 49, etc., which means that C1 = 3 + (24 X 1) = 27)) discovered in the first half of October 2011 (period 2011 T).

2011 TC4 has an 666 day orbital period and an eccentric orbit tilted at an angle of 3.13° to the plane of the Solar System, which takes it from 0.41 AU from the Sun (i.e. 41% of he average distance at which the Earth orbits the Sun, and slightly outside the orbit of the planet Mercury) to 2.57 AU from the Sun (i.e. 257% of the average distance at which the Earth orbits the Sun, and somewhat more than the orbit of the planet Mars). It is therefore classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). This means that close encounters between the asteroid and Earth are extremely common, with the last having occurred in November 2011 and the next predicted in October 2022. As an asteroid probably larger than 150 m in diameter that occasionally comes within 0.05 AU of the Earth, 2010 GT7 is also classified as a Potentially Hazardous Asteroid.
2010 GT7 also has frequent close encounters with the planets Mercury, which it last came close to in September 2014 and is  next predicted to pass in November 2033, Venus, which it last came close to in June 2001 and is predicted to pass again in December 2033, and Mars, which it last came close to in February 1968 and is next predicted to pass in October 2193. Asteroids which make close passes to multiple planets are considered to be in unstable orbits, and are often eventually knocked out of these orbits by these encounters, either being knocked onto a new, more stable orbit, dropped into the Sun, knocked out of the Solar System or occasionally colliding with a planet.
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Thursday, 13 June 2019

Danish airport worker struck by lightning.

A Danish airport worker is being treated in hospital after being struck by lightning on Wednesday 12 June 2019. The 58-year-old man was working at Copenhagen Airport when a thunderstorm broke suddenly in the evening, and was struck in the airport grounds. He was rushed to the Rigshospitalet, where his condition is described as 'not dangerous'. A house in the town of Dragør, just outside Copenhagen, was also struck by lightning, resulting in a small fire, though nobody was injured in this incident.

Copenhagen Airport. Google Maps.

Thunderstorms occur when warm, moist bodies of air encounter cooler, drier air packages. The warm air rises over the cooler air until it rises above its dew point (the point where it cools to far to retain its water content as vapour), and the water precipitates out, falling as rain, sleet or hail.

Warm moist air passing over the surface of the Earth acts as an electrical generator, creating a negative charge in the cloud tops and a positive charge at the ground (or occasionally in a second cloud layer). The atmosphere acts as an electrical insulator, allowing this potential to build up, until water begins to precipitate out. This allows a channel of ionised air to form, carrying a current between the clouds and the ground, which we perceive as lightning.

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Muntiacus gigas: A new specimen of the Giant Muntjac from the Early Holocene of northern Vietnam.

Muntjacs, Muntiacus spp., are small solitary Deer found across South, Southeast, and East Asia, though with their earliest fossils found in the Miocene of Central Europe. The genus currently contains about a dozen species, with several having only been described in the last few decades. The living Giant Muntjac was first described from northern Vietnam as Megamuntiacus vuquangensis, in 1994, being placed in a separate genus on account of its larger size, though this was later considered to be erroneous, as the species is not sufficiently genetically distinct to justify this. It was then realised that the species was identical to one described from Hemudu, a Middle Holocene (6000-7000 years old) Neolithic site in Zhejiang Province in eastern China, as Muntiacus gigas, in 1990, and then thought to represent an extinct Muntjac species. Since the Chinese specimen was named first, this name takes precedence, and is considered the valid name for the species. The species is currently confined to the Annamite Mountains of Vietnam, Laos, and Cambodia, with this range inferred mostly from hunting trophies in museum collections, and is currently considered to be Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, with a high likelyhood of going extinct within the next 20 years. However, the presence of the species in the Middle Holocene of eastern China suggests that the species once had a much greater range.

In a paper published in the journal Royal Society Open Science on 13 March 2019, Christopher Stimpson of the School of Natural and Built Environment at Queen’s University Belfast, Benjamin Utting of the Department of Archaeology at the University of Cambridge, Shawn O’Donnell, also of the School of Natural and Built Environment at Queen’s University Belfast, Nguyen Huong of the Institute of Archaeology at the Vietnam Academy of Social Sciences, Thorsten Kahlert, again of the School of Natural and Built Environment at Queen’s University Belfast, Bui Manh of the Department of Tourism of Ninh Bình Province, Vietnam, Pham Khanh of the Tràng An Landscape Complex Management Board, and Ryan Rabett, once again of the School of Natural and Built Environment at Queen’s University Belfast, describe a new specimen of Muntiacus gigas from an Early Holocene archaeological site in the Tràng An World Heritage Area in Ninh Binh Province, northern Vietnam.

The Tràng An World Heritage Area lies on the southern margin of the Red River Delta in Ninh Binh Province, northern Vietnam, and comprises a karstified (eroded) limestone massif covered by forest that rises from the coastal plain. The Hang Boi Cave Complex is an archaeological site within this area, comprising a series of interconnecting caverns with a southeast-facing entrance, which shows signs of having been inhabited during the Late Pleistocene and Early Holocene,

The specimen in the study (HBC-27587) comes from a midden pile at the entrance to the cave, comprising largely Mollusc shells, but also bones from other Mammals, Birds and Turtles. The specimen is a partial mandible (jaw bone) identified on the basis of bone and tooth anatomy as belonging to Muntiacus gigas. The specimen has been dated to between 11 100 and 11 400 years old.

Specimen HBC-27587 shown in lateral (b), medial (c), dorsal (d ) views and occlusal surfaces of m2 and m3 (e). All scale bars ¼ 20 mm. Stimpson et al. (2019).

The presence of Muntiacus gigas in the Early Holocene of northern Vietnam is not surprising, given that the species is known to have ranged as far as eastern China in the past. However the environment at Hang Boi is very different to that occupied by the species today, suggesting that it has altered its habits in response to Human pressure; modern Giant Muntjacs are found in dense forests in the Annamite Mountains, sometimes at 1200 m above sealevel. However the Tràng An specimen, while it may have been carried a short distance by Humans before being deposited, appears to have lived in a very different environment, on a lowland plane at most 200 m above sealevel, which is interpreted as having been covered by an open Oak woodland during the early Holocene.

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Wednesday, 12 June 2019

Crocodiles killed in the Solomon Islands after villager eaten earlier this month.

Police officers have killed four large Crocodiles Kolombangara Island in the Solomons, following the death of a villager believed to have been eaten by one of the animals earlier this month. The man went missing on 2 June 2019 while swimming near Kaza Village. Human remains thought to belong to the missing man were found in the stomach of a four metre Crocodile. The Solomon Islands are home to a population of Saltwater Crocodiles, Crocodylus porosus, which has grown steadily since the hunting of Crocodiles for their skins was banned 30 years ago. In recent years this has lead to a growing conflict between Humans and Crocodiles, as rising numbers of both species has brought them closer together, resulting in more Crocodile attacks on Humans, and more frequent organised culls of Crocodiles in return.

A Crocodile killed during a cull in the Solomon Islands in 2018. Peter Iroga/Facebook.

Crocodile attacks on Humans are relatively rare, but they are opportunistic ambush predators and will potentially attack anything going close to the water. Saltwater Crocodiles have a particularly poor reputation for such behaviour, being the largest species of Crocodile and notoriously aggressive. These Crocodiles are one of the few Crocodile species not considered vulnerable to extinction, being found from India to Australia  and inhabiting many areas that Humans shun, such as Mangrove forests and islands without fresh water.

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