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A Flea's Fantastic Jump Takes More Than Muscle | Deep Look
A Flea's Fantastic Jump Takes More Than Muscle | Deep Look Ambakisye-Okang Dukuzumurenyi 28 Views • 5 years ago

Before they can bite your cat or dog, these little "itch hikers" make an amazing leap 100 times faster than the blink of an eye. So how do they do it?

DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.---Spring is here, and with it, the start of flea season. With the warming weather, people and their pets are spending more time outside — which increases the chances of bringing home a hungry “itch hiker.”While pet owners curse the tiny insects and look for a way to rid them from their homes, it turns out fleas actually perform some remarkable athletic feats, like jumping 50 times their height — the equivalent of a human jumping 300 feet — or leaping so fast that they take off 100 times faster than the blink of an eye.No larger than a sesame seed and flattened side to side, fleas can slip through fur with ease. Their jump is so fast they seem to simply vanish and reappear somewhere else.“It's there and then it's gone,” said Gregory Sutton, a professor of biomechanics at the University of Lincoln in the United Kingdom.

--- What do flea eggs look like?After feeding on blood, adult fleas mate and lay eggs. The eggs drop out of their host animal’s fur or feathers and into their bedding or nest. The eggs are translucent white and very small. At 0.5mm the eggs are about the size of a grain of salt.

--- Why do fleas bite me?Blood is a protein-rich food for fleas. Adult fleas feed on blood before they can procreate.

--- Why does my dog/cat keep getting fleas?Fleas are nest parasites. Their eggs fall from the host animal into its bedding where they hatch. The worm-like larvae feed on organic debris (including the adult fleas’ feces) in the bedding. They then curl up into a cocoon and undergo metamorphosis into their adult form. Flea baths tend to kill the fleas currently on the pet, but there may still be flea eggs and larvae in the pet’s bedding. When those young fleas mature they may reinfest the pet.

Read the entire article on KQED Science:
https://www.kqed.org/science/1....957872/a-fleas-fanta

For more information:Why do Large Animals Never Actuate Their Jumps with Latch-Mediated Springs? Because They can Jump Higher Without Them. (Gregory P Sutton, Elizabeth Mendoza, Emanuel Azizi, Sarah J Longo, Jeffrey P Olberding, Mark Ilton, Sheila N Patek)https://academic.oup.com/icb/a....rticle/59/6/1609/554

President Isaias Afwerki | Talk to Al Jazeera [2010]
President Isaias Afwerki | Talk to Al Jazeera [2010] Ambakisye-Okang Dukuzumurenyi 33 Views • 5 years ago

Twenty years after the liberation from Ethiopia, Eritrea, Africa's youngest nation, has emerged as strategically vital to the stability of the region and the wider global agenda. Eritrea is struggling to balance the needs of its people with the perceived threats to the nation.Al Jazeera's Jane Dutton conducts a rare interview with Isaisas Afewerki, the president of Eritrea.Al Jazeera confronted him with the allegations about Eritrea's ties with Iran, Hamas, al Shabab in Somalia and rebel groups in Sudan and Houthis in Yemen."This is a deliberate distortion of facts, where is the evidence, these are fabrications, where is your evidence?", he said."How possibly could one blame Eritrea for sympathising or supporting one group over another in Somalia we have never done that." he said. When asked about Eritrea's relation with Ethiopia today and the border dispute he said: "This border issue war was a senseless conflict instigated by the US."It is a cover up for the failures of the misguided policies of the United States in the horn of Africa for the last 20 years."It is not a problem with Ethiopia we have worked with these people for almost two decades to remove a government in Ethiopia, and we want to see a relationship between Eritrea and Ethiopia based on mutual respect and common interest," he said."There is no presence for Iran in this region, Eritrea is not for sale, not for Iran, Israel, the United States or anybody," he said.

Fidel Castro por Carlos Moore.
Fidel Castro por Carlos Moore. Ambakisye-Okang Dukuzumurenyi 35 Views • 5 years ago

Fidel Castro por Carlos Moore.
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Carlos Moore (Nascido Charles Moore Wedderburn em Cuba, em 1942), é um escritor, pesquisador e cientista social dedicado ao registro da história e da cultura negra.
É conhecido internacionalmente pela luta contra o racismo, pelo panafricanismo e por ter escrito a biografia autorizada do cantor, saxofonista e ativista nigeriano Fela Kuti:"Fela, Esta vida Puta"

Biografia
Sua família era formada por pessoas de diversas ilhas das Antilhas: o pai biológico era de Trinidad e os pais dele, seus avós, eram de Barbados; o pai que o adotou era jamaicano e a mãe era natural de ilhas da região.
Ele viveu em Cuba até os 15 anos e mudou-se para Nova Iorque, Estados Unidos, em 1958. Lá conheceu Maya Angelou, com quem aprendeu muito sobre justiça racial e o pensamento intelectual negro. Retornou a Cuba em seguida juntando-se ao movimento revolucionário liderado por Fidel Castro. Ele concordava com os princípios revolucionários, mas discordava das autoridades sobre a discriminação racial persistente em Cuba.
Depois de ser preso algumas vezes, deixa a ilha em 1963, rumo à França. Lá ele conhece outros ativistas negros como o senegalês Alioune Diop e o filósofo poeta da Martinica Aimé Césaire e passa a trabalhar como jornalista na Agence France-Presse. Na França, inicia sua vida acadêmica e trabalha também como jornalista.
Ao longo de sua carreira como militante, esteve ao lado de Malcolm X, Cheikh Anta Diop, Aimé Césaire, Stokely Carmichael, Lelia Gonzalez, Walterio Carbonell, Abdias Nascimento, Harold Cruse, Alex Haley.
Desde 2000 ele vive no Brasil com a família, aproveitando para escrever suas memórias e conhecer mais da cultura latino-americana.
Vida acadêmica
Sua carreira como acadêmico e pesquisador foi marcada pelo título de Doutor em Etnologia, em 1979, e Doutorado em Ciências Humanas, em 1983, ambos pela Universidade de Paris-7.
Entre 1984 e 2000 foi Professor Visitante na Universidade Internacional da Flórida (EUA), Universidade do Caribe (Trinidad-Tobago), e Universidade do Caribe Francês (Martinica e Guadalupe).

Obras
Marxismo e a questão racial: Karl Marx e Friederich Engels frente ao racismo e à escravidão. Belo Horizonte: Nandyala Editora, 2010.
• Pichón: Race and Revolution in Castro´s Cuba, Chicago : Lawrence Hill Books, 2008.
• A África que Incomoda: sobre a problematização do legado africano no quotidiano brasileiro, Belo Horizonte: Nandyala Editora, 2008.
• Racismo e Sociedade: Novas bases epistemológicas para entender o racismo, Belo Horizonte: Mazza Edições, 2007.
• African Presence in the Americas, Trenton, NJ : Africa World Press, 1995;
• Castro, the Blacks, and Africa, Los Angeles : CAAS/UCLA, 1989.
• Were Marx and Engels Racists? - The prolet-Aryan outlook of Marx and Engels, Chicago : IPE, 1972.

Revealing the Leopard | Documentary
Revealing the Leopard | Documentary Ambakisye-Okang Dukuzumurenyi 51 Views • 5 years ago

The leopard (Panthera pardus) is a member of the Felidae family with a wide range in some parts of Africa and tropical Asia, from Siberia, South and West Asia to across most of sub-Saharan Africa. It is listed as Near Threatened on the IUCN Red List because it is declining in large parts of its range due to habitat loss and fragmentation, and hunting for trade and pest control. It is regionally extinct in Hong Kong, Singapore, Kuwait, Syria, Libya and Tunisia.

The leopard /ˈlɛpərd/ is the smallest of the four "big cats" in the genus Panthera. Compared to other members of the Felidae, the leopard has relatively short legs and a long body with a large skull. It is similar in appearance to the jaguar, but is smaller and more slightly built. Its fur is marked with rosettes similar to those of the jaguar, but the leopard's rosettes are smaller and more densely packed, and do not usually have central spots as the jaguars do.

Both leopards and jaguars that are melanistic are known as black panthers.The species' success in the wild is in part due to its opportunistic hunting behavior, its adaptability to habitats, its ability to run at speeds approaching 58 kilometres per hour (36 mph), its unequaled ability to climb trees even when carrying a heavy carcass,[2] and its notorious ability for stealth. The leopard consumes virtually any animal that it can hunt down and catch. Its habitat ranges from rainforest to desert terrains.

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