Sunday, 18 August 2019

Siberian mine evacuated after fire breaks out.

A coal mine in the Kemerovo Oblast of Siberia had to be evacuated after a fire broke out on Saturday 17 August 2019. The incident happened at the Gramoteyevskaya Coal Mine in Belovsky District at about 1.10 am local time, due to a fault on a conveyor belt. Forty eight workers were in the mine at the time, forty three of whom were able to make their way out unaided, with the remaining five waiting in a safe area until they could be led out by rescue workers (many modern mines have isolated safe areas with separate ventilation systems and communications, enabling miners to wait out exactly this sort of problem). Nobody was hurt in the incident, and the evacuation was of a purely precautionary nature.

The approximate location of the Gramoteyevskaya Coal Mine. Google Maps.

Coal is formed when buried organic material, principally wood, in heated and pressurised, forcing off hydrogen and oxygen (i.e. water) and leaving more-or-less pure carbon. Methane is formed by the decay of organic material within the coal. There is typically little pore-space within coal, but the methane can be trapped in a liquid form under pressure. Fire is much feared in coal mines due to this combination of flammable gas and solids, with methane and coal dust both potentially explosive when they come into contact with naked flames. To make matters worse, the limited oxygen supply in mines often means that such fires will involve incomplete combustion, in which all the oxygen is used up, but instead of forming carbon dioxide forms the much more deadly carbon dioxide, with potentially lethal consequences for anyone in the mine.

See also...
Follow Sciency Thoughts on Facebook.

Saturday, 17 August 2019

Leptarctus primus: Determining the diet of a Miocene Carnevoran.

Leptarctus primus is an Carnevoran Mammal known from the Miocene of the United States. Its relatioship to modern groups is somewhat uncertain, with the species previously regarded as a Bear or a Raccoon, and currently thought to be related to the Mustelids (Weasels, Badgers and Otters). Similarly the diet of Leptarctus primus, and therefore the ecological nich it occupied, has been the subject of some debate, with its skull being interpreted as suggesting a diet similar to that of the carnivorous American Badger, Taxidea taxus, the omnivorous Raccoon, Procyon lotor, the leaf-eating Koala, Phascolarctus cinereus, the frugivorous Kinkajou, Potos flavus, the insectivorous Bat-eared Fox, Otocyon megalotis, or the omnivorous Raccoon Dog, Nyctereutes procyonoides.

In a paper published in the Journal of Vertebrate Paleontology on 22 February 2019, Alixandra Prybyla of the Department of Ecology, Evolution, and Environmental Biology at Columbia University, and the Division of Paleontology at the American Museum of Natural History, Zhijie Jack Tseng of the Department of Pathology and Anatomical Sciences at the State University of New York, Buffalo, and John Flynn, also of the Division of Paleontology at the American Museum of Natural History, and of the Department of Earth and Environmental Science at Columbia University, and the Richard Gilder Graduate School, describe the results of a study of Leptarctus primus in which computer simulation of cranial biomechanics is used to compare it to a variety of living species.

Prybyla et al. CT-scanned the crania of a number specimens using high-resolution micro-computed tomography with the GE v|tome|x s 180/240 kV dual-tube HRX μCT system at the Microscopy and Imaging Facility of the American Museum of Natural History. As well as several specimens of Leptarctus primus, the study included Hypsoparia bozemanensis, a second Miocene North American Carnavoran, which is known only from a single fragmentary specimen, and which some palaeontologists ague is a specimen of Leptarctus primus, as well as the Eocene Carnivoran Oodectes herpestoides, and the Eocene Hyeanadont Creodont Thinocyon velox. The study also included the modern Ring-tailed Cat, Bassariscus astutus, Wolverine, Gulo gulo, Kinkajou, Potos flavus, Eastern Spotted Skunk, Spilogale putorius, American Badger, Taxidea taxus, Grey Fox, Urocyon cinereoargenteus, Wolf, Canis lupus, Black-backed Jackal, Canis mesomelas, Polar Bear, Ursus maritimus, Brown Bear, Ursus arctos, African Wild Dog, Lycaon pictus, Spotted Hyena, Crocuta crocuta, Brown Hyena, Parahyaena brunnea, Red Panda, Ailurus fulgens, Leopard, Panthera pardus, Javan Mongoose, Herpestes javanicus, Striped Skunk, Mephitis mephitis, and the Raccoon, Procyon lotor.

Leptarctus primus skull reconstructions and models. (A) AMNH FM 25385, reconstruction of missing or damaged morphology, accounted for in virtual reconstruction: occipital condyles, anterior cranial crushing, and a loss of maxillary canines. The protrusion of the left sagittal crest has broken off; it has not been reattached. The neotype (AMNH FM 18241) of Leptarctus primus was used as a reference for the reconstruction. (B) CTscanned, evaluated to identify collapsed elements and holes, and slice artifacts produced by the coronal image stack compilation smoothed in Mimics to create a computerised model of the original skull. (C) model (B)’s triangular surface elements lowered via the ‘decimation function’ to a more uniform number (between 200,000 and 280,000 finite elements), reducing the topical quality of the mesh but standardising it with other models. Because canines are lacking in AMNH FM 18241, the canines were transferred digitally from the best-preserved Leptarctus specimen (AMNH FM 54198) in the collection. Prybyla et al. (2019).

This data set was used to create a three dimensional stress distribution maps of the crania, showing where stress would be applied during biting, where the greatest bite force would be applied, and the strength of this bite force, with a view to understanding the feeding mechanics of Leptarctus primus, and therefore estimate its ecological role.

Von Mises stress distributions in crania of extinct Leptarctus primus and extant Taxidea taxus, Potos flavus, Lycaon pictus, and Gulo gulo. Unilateral bites are shown for the right upper tooth row, with C (canine), P2 (second premolar), P3 (third premolar), P4 (fourth premolar), and M1 (first molar). Cooler (darker) shades indicate lower stress; warmer (lighter) shades indicate higher stress. Prybyla et al. (2019).

Leptarctus primus was found to be most similar to the American Badger, Taxidea taxus, a primarily carnivorous species, which has some omnivorous habits. The diet of the American Badger comprises mostly small Vertebrates, such as Snakes, and Birds, supplemented secondarily by opportunistic omnivorous feeding on Insects, eggs, seeds, Fungi, etc.. It also shows some similarities to the African Wild Dog, Lycaon pictus, another largely carnivorous species the omnivorous Raccoon, Procyon lotor, and the Wolverine, Gulo gulo, a carnivore which feeds largely on scavenged carrion, but again is opportunistically omnivorous.

See also...
Follow Sciency Thoughts on Facebook.

Leopard attack thwarted by Dog in Darjeeling.

A Dog has thwarted a Leopard attack on its owner in the town of Sonada in Darjeeling District, West Bengal State, India. The incident happened on Wednesday 14 August 2019, when Aruna Lama, 58, heard a disturbance in a storage area beneath her kitchen, where the family kept some live Chickens. She went to investigate the noise, and when she opened the door, was pounced on by a Leopard, which seized her by the head and trying to drag her away. The Leopard quickly abandoned the attack when it was set upon by the family Dog, a four-year-old Tibetan Mastiff Cross called, Tiger, who was adopted by the family in 2017 after being found in a half-starved state. Confronted with the angry Dog the Leopard fled the scene, with Dog in pursuit, and has not been seen since, though officials from the Indian Forest Service are attempting to capture it for relocation.

Aruna Lama, 58, of Sonada in Darjeeling, saved from a Leopard attack by her Dog on 14 August 2019. Times of India.

Leopards are considered to be Vulnerable under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, with the Indian subspecies, Panthera pardus fusca, considered to be particularly vulnerable due to India's rapidly rising Human population, which has resulted in agriculture and other Human activities expanding into many former wilderness areas. For this reason the Indian Forest Service usually try to relocate Leopards that come into conflict with Humans to more remote areas, preferably within national parks, though the extent to which local people co-operate is variable.

Tiger, a four-year-old Tibetan Mastiff cross that saved his owner from a Leopard attack in Darjeeling on 14 August 2019. Times of India.

See also...
Follow Sciency Thoughts on Facebook.

Friday, 16 August 2019

Three dead as Tropical Storm Krosa makes landfall in Japan.

Three people have died and more than fifty more have been injured after Tropical Storm Krosa made landfall on Honshū Islands, Japan, close to Kure City in Hiroshima Prefecture, at about 3.00 pm local time on Thursday 15 August 2019. Neneko Mori, 11, died after being swept out to sea with her sister near Shimoda City; her body was later recovered at Shizuoka on the other side of Suruga Bay, her sister was able to swim back to shore alive. In Hyogo Prefecture fisherman Noriyuki Kumabuchi, 71, died after being swept into a river, and in in Onomichi in Hiroshima Prefecture an 82-year-old man died after being swept into the sea while tyong up a boat.

Large waves associated with Tropical Storm Krosa at Shirahama in Wakayama Prefecture. Tatsuya Onishi/Mainichi.
Wakayama Prefecture

The storm brought with it very high rainfall, with 869.5 mm of rain recorded in three hours at Yanase in Kochi Prefecture. This triggered a number of landslides, which are not thought to have caused any injuries but which have blocked roads in some areas. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. Other transport networks have also been disrupted, with numerous flights and rail services cancelled due to the storm.

Waves associated with Tropical Storm Krosa in Miyazaki Prefecture. Kyodo News/Reuters.

Tropical storms are caused by the warming effect of the Sun over tropical seas. As the air warms it expands, causing a drop in air pressure, and rises, causing air from outside the area to rush in to replace it. If this happens over a sufficiently wide area then the inrushing winds will be affected by centrifugal forces caused by the Earth's rotation (the Coriolis effect). This means that winds will be deflected clockwise in the northern hemisphere and anti-clockwise in the southern hemisphere, eventually creating a large, rotating Tropical Storm. They have different names in different parts of the world, with those in the northwest Pacific being referred to as typhoons.

 A tree uprooted by Tropical Storm Kroda in Hiroshima. Kyodo News.

Despite the obvious danger of winds of this speed, which can physically blow people, and other large objects, away as well as damaging buildings and uprooting trees, the real danger from these storms comes from the flooding they bring. Each drop millibar drop in air-pressure leads to an approximate 1 cm rise in sea level, with big tropical storms capable of causing a storm surge of several meters. This is always accompanied by heavy rainfall, since warm air over the ocean leads to evaporation of sea water, which is then carried with the storm. These combined often lead to catastrophic flooding in areas hit by tropical storms.

See also...
Follow Sciency Thoughts on Facebook.

Seventeen missing in landslide in Sichuan Province, China.

Seventeen people are still missing after a landslide hit construction workers working in a railroad in Ganluo County in in Siichaun slightly before 12.45 pm on Wednesday 14 August, The incident buried about 70 metres of the Lianghong-Aidai section of the Chengdu-Kunming Railway, while maintenance work was being carried out. Eleven people were pulled from the debris alive, but it is becoming increasingly unlikely that further survivors will be found as time passes. The landslide was the latest in a series of events in the area, triggered by exceptionally heavy rains across South China this summer. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

A section of the Chengdu-Kunming Railway, buried by a landslide on 14 August 2019. Liu Zhongjun/China Daily.

The climate of Sichuan Province is heavily influenced by the Asian Summer Monsoon, with heavy rainfall common in the summer. Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate. This situation is particularly intense in South Asia, due to the presence of the Himalayas. High mountain ranges tend to force winds hitting them upwards, which amplifies the South Asian Summer Monsoon, with higher winds leading to more upward air movement, thus drawing in further air from the sea.

Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

See also...
Follow Sciency Thoughts on Facebook.

Thursday, 15 August 2019

Camper attacked by Wolf in Banff National Park.

A New Jersey man is recovering after being attacked by a Wolf in Banff National Park in Alberta Province, Canada. Matthew Rispoli was sleeping in a tent with his wife and two sons at about 1.00 am on Friday 9 August 2019, when a solitary adult male Grey Wolf, Canis lupis, ripped through the side of the tent and seized Mr Rispoli by the arm, initiating a struggle lasting several minutes, during which Mr Rispoli was unable to dislodge the Wolf, but the Wolf was unable to drag him away. This struggle ended abruptly when a neighbouring camper kicked the Wolf, causing it to flee. The Wolf was later shot by trackers from Parks Canada, who were able to confirm its identity using DNA swabbed from Mr Rispoli's wounds.

American tourist Matthew Rispoli, attacked by a Wolf in the Banff National Park. CNN.

Wolf attacks on Humans are exceptionally rare, as we are difficult prey for them, and hard to subdue, with Parks Canada only having recorded two previous incidents, one in British Columbia and one in Ontario. The Wolf in the Banf Park attack is reported to have been severely underweight, at about 35 kg, compared to a typical healthy adult bodyweight of 45-70 kg, and was presumably having trouble feeding by itself; Wolves are pack animals and often have trouble capturing prey on their own.

See also...
Follow Sciency Thoughts on Facebook.

Asteroid PS1 passes the Earth.

Asteroid 2019 PS1 passed by the Earth at a distance of about 827 000 km (2.01 times the average  0distance between the Earth and the Moon, or 0.55% of the distance between the Earth and the Sun), slightly before 5.30 pm GMT on Friday 9 August 2019. There was no danger of the asteroid hitting us, though were it to do so it would not have presented a significant threat. 2019 PS1 has an estimated equivalent diameter of 8-26 m (i.e. it is estimated that a spherical object with the same volume would be 8-26 m in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) in the atmosphere between 35 and 20 km above the ground, with only fragmentary material reaching the Earth's surface.

 The calculated orbit of 2019 PS1. JPL Small Body Database.

2019 PS1 was discovered on 10 August 2018 (the day after its closest approach to the Earth) by the Zwicky Transient Facility at Palomar Observatory in California. The designation 2019 PS1 implies that it was the 42nd asteroid (asteroid S1 - 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 S1 = 18 + (24 X 1) = 42) discovered in the first half of August 2019 (period 2019 P).

2019 PS1 has a 703 day orbital period and an eccentric orbit tilted at an angle of 2.00° to the plane of the Solar System, which takes it from 0.90 AU from the Sun (i.e. 90% of he average distance at which the Earth orbits the Sun) to 2.19 AU from the Sun (i.e. 219% of the average distance at which the Earth orbits the Sun, and considerably outside 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 occasionally occur, with the last having occurred in March this year, and the next predicted for April 2021.

See also...
Follow Sciency Thoughts on Facebook.