Both black and white mantas can be seen together in some locations, however, the white underside coloration is always more dominant. Both Manta birostris and Manta alfredi species have a black coloration. These mantas are predominantly black on their ventral surface with small spots or patches of white. The most extreme difference in manta coloration comes with the “black manta”. These spot patterns are unique to each manta and can be used for accurate identification. Typically, Manta birostris has few spots ventrally with wide gray bands along the back edge of the wings. Manta alfredi has big blotchy spot patterns ventrally located. While the dorsal coloration is relatively similar in mantas worldwide, their ventral side can be very different. Typically, manta rays are black dorsally with white dorsal shoulder bars. Manta alfredi is the species of manta ray that is sighted on the Kona manta ray night tours. The species is widespread in tropical waters and found in the Atlantic, Indian, and Pacific oceans. Manta birostris is occasionally sighted along the Kona Coast. This species is commonly sighted near shore around coral reefs, often times in residential groups. Manta alfredi is a smaller species that has an average size of 11’ across. They are regularly sighted at offshore islands, oceanic seamounts, and submarine ridge systems. Manta birostris are located in the Atlantic, Indian and Pacific oceans. ![]() ![]() Manta birostris typically roam the open ocean and are migratory. When furled, these fins were thought to resemble a devil’s horns.īased on a study conducted by Marshall (2009), manta rays are divided into two different species: Manta birostris and Manta alfredi. To make the fins more streamlined, devil rays can roll up these flexible appendages. When unfurled, the fins help to funnel in food and water into the mouth. Devil rays share the common characteristic of cephalic or head fins. ![]() Manta rays belong to the family of rays referred to as devil rays, scientifically called Mobulidae. A stingray's mouth is located on the underside of its body whereas the mouth of the manta ray is along the front edge of its body. Stingrays dwell on the ocean bottom, but manta rays live in the open ocean. One of the biggest differences between manta rays and stingrays is that manta rays do NOT have a tail "stinger" or barb like stingrays. Both have flattened body shapes and wide pectoral fins that are fused to the head. They do possess a tooth band that is more like sandpaper along the lower jaw only. Unlike many shark species, manta rays do NOT have sharp teeth. Sharks and rays are grouped together in a sub-class called Elasmobranchii. ![]() Sharks and rays are cartilaginous fishes and belong to the scientific classification Chondrichthyes. Like many other open ocean animals, manta rays have countershading coloration - dark on the topside (dorsal side) and light on the underside (ventral side). Their broad blanket-like bodies earned them the name manta that means cloak or blanket in Spanish. With a diamond shaped body and wing spans reaching over 20’ across, manta rays are one of the largest animals in the ocean. Their side or pectoral fins have evolved into wide triangular wings that they use to easily propel themselves through the water. Manta rays are large sea animals that live in tropical, sub-tropical, and temperate waters worldwide.
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![]() When visibility reaches less than 5 miles, smoke has reached an unhealthy level. ![]() You may want to remain indoors or limit time outdoors during the worst of the smoke, especially if you suffer from heart or respiratory issues or are very young or old, according to the Colorado Department of Public Health and Environment. What you should do to protect yourself from the wildfire smoke ![]() The province has seen 292 wildfires this season.Īround 1 million acres have burned in western Canada this year. Neighboring British Columbia has 92 active fires, nearly 30% which are out of control. The province has seen 515 wildfires already this season. Alberta has nearly 80 wildfires actively burning, with nearly 30% out of control. Western Canada has been hit hard by wildfires as unprecedented heat has struck the area, according the National Oceanic and Atmospheric Administration. What's causing the smoke to pour into Colorado? Make sure to check out our fire and smoke map at /fires. Still, unusually sensitive people should continue to reduce prolonged or heavy exertion through Wednesday afternoon, the agency said. The Colorado Department of Public Health and Environment said Wednesday wildfire smoke will linger across northeastern Colorado but that concentrations have gradually decreased and air quality should continue to improve during the day on Wednesday. It added people should avoid travel into the burn areas Wednesday afternoon and those living in or near flash flood prone areas should have a plan and be ready to take action if a flash flood warning is issued. Those thunderstorms will bring an elevated risk of flash flooding to the Cameron Peak Fire burn scar, the weather service said. (Photo by Hyoung Chang/The Denver Post) By Kieran. Air quality is expected to improve Wednesday afternoon and evening as thunderstorms enter Colorado, according to the National Weather Service in Boulder. Smoke from a wildfire burning near Lake George hangs in the air south of Florissant in Teller county, Colorado on Friday, March 31, 2023. Around 10 years after the Death Eaters first surfaced, a Seer named Sybill Trelawney made a prophecy about a boy who would have the power to defeat Voldemort forever. ![]() The Death Eaters first existed over 11 years before the events of the books, torturing and murdering Muggles (people without magical abilities), as well as anyone who opposed them, including wizards who support Muggles (such as the Weasley family). They were mentioned the first time directly in Harry Potter and the Prisoner of Azkaban. The group had also been mentioned indirectly in Harry Potter and the Philosopher's Stone and in Harry Potter and the Chamber of Secrets, when followers of Voldemort were mentioned. The Death Eaters as a group first appeared in the novel Harry Potter and the Goblet of Fire, although individual members of the group, such as Severus Snape, Lucius Malfoy, and Peter Pettigrew had appeared in earlier books in the series. Their typical attire includes black hooded robes and masks. Their primary opposition is the Order of the Phoenix.ĭeath Eaters recognise one another by the Dark Mark, a sigil branded on each of their left forearms that allows Voldemort to summon any of them instantly. ![]() They attempt to create a new order within the Ministry of Magic by spreading fear through the wizarding community and murdering those who speak out against them. They are a radical group of wizards and witches, led by the dark wizard Lord Voldemort, who seek to purify the wizarding community by eliminating wizards and witches born to non-magical parents. The Death Eaters are characters featured in the Harry Potter series of novels and films. In Carol Clover's seminal 1992 study, "Men, Women, and Chain Saws," she writes that in occult and paranormal films, those who are "open" to being in tune with the paranormal are always gendered as being more "feminine." "Occult films code emotional openness as feminine, and figure those who indulge in it, male and female, as physically opened, penetrated," she writes. "Stranger Things" and the frustrations of Gen X's '80s nostalgia habitīeyond these hints subtle or big, fans of the horror genre might have known Will Byers was always going to be gay. Hopper asks if the boy is, and Joyce, exasperated, shouts: "He's missing! Is what he is." Later on in Season 3, Will is peeved that his friends' girlfriends have distracted the boys from their Dungeons & Dragons play, and Mike hollers at Will, "It's not my fault you don't like girls!" In a hushed tone, Joyce says that her ex-husband used to call the boy "queer," almost mouthing the word so no one would hear her. If this clue wasn't enough, the scene at the police station then becomes more heavy-handed in foreshadowing Will's sexuality. most." She then adds, "Look, he's a sensitive kid." In the '80s, "sensitive kid" usually signaled someone wasn't being heteronormative in terms of their performance of stereotypical gender roles. Though Hopper thinks Will might be off playing hooky, Joyce disagrees: "He's not like you, Hopper. ![]() Way back in the very first episode, after Will first disappears, his mom Joyce Byers (Winona Ryder) seeks local police chief, Hopper's (David Harbour) help. While fans may have missed these brief moments, they certainly were there in prior seasons. And it's this latter fact especially that paved the way for Will Byers' coming out.īut first, let's take a look back at the instances of coded language. ![]() not conforming with society's strict views of masculinity) were unfairly linked with the monstrous. The 1980s was also a time when cisgender boys and men considered "too feminine" (i.e. But this shyness is pretty faithful to the 1980s, a time when coded language was often employed to identify someone as queer. The show doesn't actually say he's gay outright. Fans who completed Volume 2 of "Stranger Things" Season 4 will know Will Byers (Noah Schnapp) has finally, in a roundabout way, come out as gay. ![]() Similar guidelines are used for gears, bearings, engines, etc., to assure the lubricant flows to the various components at low temperature start-up and protects against wear at operating temperature.įigure 1 demonstrates the various temperature operating ranges for a given operating viscosity range. OEMs also specify the minimum viscosity for the system during operation to minimize metal-to-metal contact and wear. Hydraulic pump OEMs identify the maximum viscosity allowed at system start-up to ensure the fluid will flow and avoid pump damage due to cavitation (see the February 2022 TLT Lubrication Fundamentals article titled Air entrainment, aeration, cavitation and foaming: How are they related?). The temperatures at which the oil reaches the maximum and minimum allowable viscosities determines the operating range. Thus, original equipment manufacturers (OEMs) specify maximum and minimum allowable viscosities to protect their equipment. This is important because lubricated equipment is subject to extreme temperatures: cold at start-up until the unit has warmed up, potentially to extremely hot at times. Non-EP lubricant grades are rust and oxidation inhibited, only EP Lubricants are mild Extreme Pressure type.Oil viscosity varies with temperature so much so that an oil’s viscosity should always be qualified with the temperature at which the viscosity is measured. Note: Compounded oils must have 3-10% suitable animal fats. ![]() The American Gear Manufacturers Association (AGMA) and the International Standards Organization (ISO) have established viscosity standards for hydraulic fluids and industrial gear lubricants.įollowing are the AGMA Lubricant Numbers, the corresponding ISO Grade and the viscosity ranges: Axle and Manual Transmission Lubricant Viscosity ClassificationĪGMA and ISO Viscosity Grade Classifications.Following is a table with the SAE gear lubricant viscosity grades: For instance, an SAE 80W gear lubricant may have the same viscosity as an SAE 20W or SAE 30 engine oil and SAE 90 gear lubricant viscosity can be similar to that of an SAE 40 or SAE 50 engine oil. A gear lubricant and an engine oil having the same viscosity will have widely different SAE viscosity grade designations as defined in the two viscosity classifications. Gear lubricant viscosity grades should not be confused with engine oil viscosity grades. The Society of Automotive Engineers (SAE) has devised a method for classifying the viscosity characteristics of gear lubricants as well. Following is the API description: SAE Viscosity Grades for Gear Lubricants ![]() The automotive and petroleum industries in cooperation with the American Society of Testing and Materials (ASTM), Society of Automotive Engineers (SAE) and the American Petroleum Institute (API) have developed a service classification system to serve as a guide for recommending and marketing gear lubricants. ![]() Viscosity Temperature Chart API Service Designation for Gear Lubricants SAE Viscosity Grades for Engine Oils – SAE J300 Dec 99 The chart shown at the bottom of the page graphically represents the viscosity-temperature relationship of the SAE grading system with lines drawn to show the viscosity characteristics for several popular motor oils. The Society of Automotive Engineers (SAE) viscosity grading system for engine oils consists of “W” grades that define low temperature viscosities and “straight” grades that put further limits on high temperature viscosities. |