Jurassica Nephila

Un equipo de científicos ha descubierto el fósil más grande de una araña encontrado hasta el momento. Data del Jurásico Medio, hace unos 165 millones de años, cuando los dinosaurios dominaban la Tierra y ha sido publicado en la revista Biology Letters. Los investigadores la han 'bautizado' como Jurassica nephila. Aunque su cuerpo no era excesivamente grande, sus patas podían alcanzar hasta los 15 cm de longitud, lo que convierte a este ejemplar "en el fósil arácnido más grande conocido", señala Paul Selden, profesor de la Universidad de Kansas (EE.UU.).
El ejemplar ha sido descubierto en una formación rocosa rica en fósiles en el yacimiento de Daohugou, en Mongolia Interior (China), donde también se han encontrado restos fósiles de salamandras, pequeños mamíferos e incluso de otra araña de 165 millones de años de antigüedad.

La araña, según recoge la BBC, fue sepultada por ceniza volcánica en el fondo de lo había sido un lago. Pero independientemente de las circunstancias que motivaron su muerte, reconocen los expertos, la conservación del fósil es excelente. Los registros fósiles de este género de arañas son muy escasos porque sus cuerpos se destruyen con mucha facilidad. Hasta la fecha, el más antiguo databa de hace 34 millones de años, por lo que las Nephilas son 130 años más antiguas de lo que se pensaba. Además, este descubrimiento, sitúa a las Nephilas en el periodo jurásico, lo que las convierte en el género de arañas más antiguas conocidas por la ciencia.

Información extraida de:

            astronomia-fisica-misiones-espaciales.blogspot.com

            www.noticiasciencias.com

La Eugenesia

La Eugenesia

 Juan Francisco Torres, Lidia Sánchez, Jesús Torresano, Javier Rico, Belén Vicente

Ciencias para el Mundo Contemporáneo

1ºB Bachillerato

ARTÍCULO DE OPINIÓN: LA EUGENESIA

En esta época en la que el desarrollo científico y tecnológico avanza a un ritmo de vértigo, los dilemas morales que se nos plantean son cada vez mayores. Un hecho que no pasa desapercibido es la eugenesia, práctica que busca la mejora de las cualidades no deseables de la especie humana. Su origen se remonta a Platón, que ya en La República dijo: “los mejores cohabiten con las mejores tantas veces como sea posible y los peores con las peores al contrario.”Estamos hablando de la antigua Grecia; sin embargo, su desarrollo ha continuado tiempo después. Aunque la práctica quedó obsoleta con el cristianismo en la Edad Media, es notoria su posterior recuperación por parte de Galton. Y qué decir de laeugenesia nazi en la que Hitler basándose en la obra de Darwin, intentó potenciar la raza aria mediante la esterilización de deficientes mentales y muerte de millones de judíos. Vasectomías y muerte a criminales en Suecia,Chile o incluso Estados Unidos(Indiana)... son sólo una diminuta parte de la infinidad de ejemplos de eugenesia negativa a lo largo de la historia. Por supuesto, esto es un hecho tremendo. Semejante acto de racismo, segregación y discriminación hacia los que presentan una deficiencia ya sea física o mental nunca debió ser permitido. Hoy en día, con el Proyecto Genoma Humano (PGH) y evolución en la manipulación genética, se está dando un nuevo tipo de eugenesia llamada positiva. Ahora bien, ¿tenemos el derecho de cambiar nuestra naturaleza y decidir cómo serán nuestros descendientes? ¿Estamos preparados para superar nuestros propios límites?.

Las consecuencias de lo que la eugenesia supone hoy día, pueden ser igual de atroces. ¿Positiva? Sólo un eufemismo para designar la misma práctica mediante distintos métodos: la terapia génica o la ingeniería genética. La base de la eugenesia actual es la mejora de la especie mediante la identificación de buenos genes, favoreciendo la reproducción de aquellas personas poseedoras de estos. Antes de alegrarse, cabría analizar el trasfondo y verdadero significado de esta práctica. El desarrollo de técnicas de análisis genético sólo supone las identificación de aquellos embriones no aptos. Éstos no serán modificados genéticamente para quitar la enfermedad, sino que se eliminarán hasta dar con uno que no suponga un problema.

Yendo más allá, el comienzo consistió en eliminar embriones portadores de minusvalías o enfermedades congénitas, posteriormente, se pasó al “bebé medicamento” que serviría de donante para sus hermanos, y lo último que prima es excluir embriones no por enfermedades congénitas, sino por probabilidad de desarrollar una enfermedad en la edad adulta. Prosiguiendo en esta línea, en cuanto al cáncer, ¿por qué no seleccionar también a los embriones que tengan una probabilidad del 20% o el 50% de padecer la enfermedad?¿Y si ya no es un cáncer sino diabetes? Quizás Aldeos Huxley no estuviese muy equivocado en suMundo Feliz. Más que un avance, supone un retroceso puesto que, qué sentido tiene molestarse en buscar una cura cuando se pueden eliminar a los más susceptibles de padecer una enfermedad.

Tal y como dijo el Dr. Tinant: “El hombre tiene hoy el poder de controlar la herencia genética y este progreso de la biología molecular, unida a los avances de la biotecnología alternativa, no debe sobrepasar los límites que impone la naturaleza humana y su propia dignidad, pudiendo aceptarse la ingeniería genética fundamentalmente con fines terapéuticos para el tratamiento de enfermedades"

Dolly, the cloned sheep

Scientists Keith Campbell and Ian Wilmut of the Roslin Institute of Edinburgh managed to successfully clone the first mammal, Dolly the sheep (July 5, 1996 - February 14, 2003) from an adult cell.

The process was as follows:

1. Were taken by biopsy, epidermal cells of the mammary gland of an adult sheep and cultured in a nutrient medium. Was gradually decreasing the protein concentration of the medium to stop cell division in culture and leave them at rest.
2. In parallel, another sheep was subjected to hormone treatments to achieve multiple ovulation. Several of the oocytes produced by the sheep were enucleated, ie the nucleus was extracted by suction through a specimen.
3. They contacted the cultured cells grown in enucleated oocyte resting and subjecting them to a brief electrical pulse to create micriporos in the membranes of both cells, emulating the acrosome reaction, and thus favor the merger and to open calcium channels, causing a reaction similar to that which causes the formation of the fertilization membrane.
4. Once achieved the fusion of enucleated oocyte with the nucleus from an adult cell, was obtained equivalent to a diploid cell zygote after the union of oocyte and sperm. This "zygote", with the same genetic makeup as the nucleus of the mammary gland of the sheep and the cytoplasm of the oocyte, was implanted and gestated in the uterus of a third sheep.
5. The result was the birth, 148 days after the sheep Dolly, genetically identical to the sheep whose mammary gland cells were extracted.

Reproductive cloning has been successfully tested in various mammals. An interesting application field is the cloning of animals in imminent danger of extinction.

TOP 5 Inventos españoles

EL SUBMARINO
Inventado por: Isaac Peral (1851-1895)
Descripción del invento e historia: El primer submarino tuvo por nombre "Isaac Peral (C-1)", fue un submarino de la Clase C de la Armada Española construido por la SECN en el astillero de Cartagena, que participó en la Guerra civil en el bando republicano.

LA RADIO

Inventado por: Julio Cervera Baviera (1854-1929)

Descripción del invento e historia: La radio es un medio de difusión masivo que llega al radio-escucha de forma personal, es el medio de mayor alcance, ya que llega a todas las clases sociales.Julio Cervera inventó la radio 11 años antes que Marconi. Julio Cervera fue reconocido justamente como el padre de la comunicación sin hilos. Este militar y científico español, experto en diseño de tranvías, además profetizó la "invasión" marroquí de la Isla Perejil.

LA FREGONA

Inventado por: Manuel Jalón Corominas (1925 - ...)

Descripción del invento e historia: La fregona es una herramienta para limpiar el suelo en húmedo y normalmente consta de un palo en cuyo extremo se encuentran unos flecos absorbentes. En principio surgió como un objeto liberador de la mujer, eminentemente feminista y que permitía a estas levantarse del suelo, no tener que estar arrodilladas para limpiar la casa.

El sacapuntas

Inventado por: Ignacio Urresti

Descripción del invento e historia: Ignacio Urresti creó el afilalápices en 1945 siendo otra de las grandes aportaciones de España al mundo del material de oficina tras la grapadora Casco. Se inspiró en un molinillo de café, y su invento se hizo muy popular de forma inmediata, además de ser considerado como un gran ejemplo de diseño.

EL CHUPA CHUPS

Inventado por: Enric Bernat

Descripción del invento e historia: Un caramelo con palo para chupar. Hoy en día, la marca Chupa Chups es reconocida en cualquier parte del mundo, y su logotipo, diseñado por Dalí, tiene la fuerza del de la Coca Cola. Bernat convirtió una pequeña empresa familiar en una gran compañía, a base de trabajo duro y de muchos kilómetros con los muestrarios.

SI QUIERES SABER +, pincha aqui: INVENTOS

GRAFFITI OR VANDALISM?

Even a small line can transform a gorgeous and beautiful painting into a expression of vandalism.

What would happen if Leonardo Da Vinci had painted a moustache on Mona Lisa?

It’s clear that most people’s answer would be, “the painting is not the same with that line”.

One day of spring of 1503, the famous artist Leonardo Da Vinci woke up in his house in Florence. Close to his bed was the first draft of La Gioconda. It looked incredibly amazing, even though unfinished.

But that day wasn’t like the others. Outside on the street, there were three young fellows laughing, with brushes in their hands.

They were painting things that Leonardo barely could see on the blacksmith shop wall.  The three guys were signing their name on a painting similar to the Mona Lisa, trying to make fun of the brand new painting of their neighbor, Da Vinci.

Suddenly, Leonardo’s voice was heard in the narrow street. – Come over here, and I’ll give you an empty canvas where you’ll be able to paint without “destroying” a public place.

For centuries artistic expressions appeared all over the world, “hoping" not to cross the fine line between art and vandalism.  Letting us know more about our undiscovered past, that will continue fascinating the humanity. Forever.

Essay about “Night” by Elie Wiesel

The relationships between the members of a family are very delicate and they can change depending of the facts that happen due to the different conditions like wars and other difficulties of the life. At the very beginning of the story, all the Jews of Sighet were relaxed in the aspect that they didn’t know that the Nazis were going to take the entire town to a concentration camp. The relationships between the families were normally pacific. The families prayed together, they played together. Almost everything was going good, until the families were taken to the transport-tracks, to the concentration camp of Auschwitz.

In the way to Auschwitz, the relationships between the members of the families started changing.  All the people were quite, thinking about their fate and imagining how was going to be their own future in the place that they won’t be, and where the most members of the families were going to be murdered.

Once in Auschwitz, the SS separated the families in women and men. Everybody was sad. Thousand of tears were flowing in every face. The unique thing that still worrying the members of families, who were with some of them, it was to continue being together. With the passage of time, the people started realizing that they had to survive with the little food that the Nazis were giving to them. Less than a loaf of bread, some coffee, soup, and it was not daily. They had to begin worrying about themselves and not worrying about look after the family. Because if the people were not strong. They would be sent to the crematorium. “The weak ones must die”. 

At the end of the Genocide, the American troops came into the concentration and death camps. They rescued the survivors. Their unique thought was, to eat a lot and awake from that nightmare. Soon they began to miss their families, and the lucky ones who had a member of the family with them, began a new life trying to forget the horrible things that they had seen in Auschwitz. The war is a horrible situation that makes change the behavior of every single person involved in the conflict. The war is a moment that flips the feelings, and it doesn’t forgive anybody. And the worst moment of a war is the end of it, when the survivors started realizing that they lost their “life” acting of a certain way to survive, “killing” the people that they love.

Theodore Roosevelt: “The most Progressive President”

Theodore Roosevelt the twenty-sixth President of the United States, but this astonishingly multifaceted man was a great many other things as well. His specific achievements are numerous. Perhaps his greatest contribution was his work for conservation. He provided federal protection for almost 230 million acres, a land area equivalent to that of all the East coast states from Maine to Florida. Theodore Roosevelt Presidential achievements are impressive. In foreign affairs he led us into the arena of international power politics, thrusting aside the American tradition of isolationism, while on the domestic scene, he reversed the traditional federal policy of laissez-faire, and sought to bring order, social justice, and fair dealings to American industry and commerce. Roosevelt found volunteers from cowboys from the Western territories to Ivy League friends from New York, forming the First U.S. Volunteer Cavalry Regiment. The newspapers called them the "Rough Riders."He’s face is in the Mount Rushmore. 

Uncle Sam

Theodore Roosevelt improved working conditions and the way of life of American people. He exposed corruption and expanded democracy. Also, the expansion of the federal government's powers, competition and economic distribution of wealth, and the social welfare of American citizens concerned many leaders during this time. However, the leading progressive political figure, Roosevelt was out to change things. Not only did the leader bring about new heights for government regulation, but he also set the standards for political intervention. Theodore Roosevelt was known as the "trust buster" and that is exactly what he did to help control big business. Roosevelt went in to these companies and helped to stop this type of monopoly.

“My life during the Great Depression”

Great Depression

What times I have had to live!  The economy was very bad. When the stock market crashed in 1929, I lost a lot of money. Then I began to go to the breadlines, that is a place where I could get free food. The luck that my family and I have had is that he has been a chosen president of United States of America, Franklin D. Roosevelt.  He established the Federal Emergency Relief Administration that is an Administration of the government to help families like mine. With the money that they gave me, I bought a small local where now my family has a pastry shop. The business is being ok. Last night I heard in the news of the radio that Amelia Earhart, in a attempt to fly around the world disappeared somewhere over the Pacific Ocean. With the economic relief that the shop has given to me, I went with my wife to the cinema to see the movie that is having  much success, “Gone with the Wind”. This is my life. I hope that no country in the world returns to live a crisis like that I have lived.

Essay of Jim Crow Laws

Jim Crow Laws

Jim Crow Laws were a group of state and local laws enacted between 1876 and 1965. The laws were about the racial segregation in all public facilities. The mane phrase of those laws was "Separated but equal". That laws, affected a lot the life the Americans of those years, for example: the white children(more cases on southern states of United States of America) were though in schools that the black people were different and inferior than them and the whites had the priority for a job and the Africans Americans didn't had that priority etc. All that acts were influencing little the thoughts of white American people, making them react against segregation of African-Americans.
The chosen law of Jim Crow Laws is the one that is about Intermarriage, enacted in the American state of Mississippi. The Law says: "The marriage of a white person with a negro or mulatto or person who shall have one-eight or more of Negro blood, shall be unlawful and avoid". My reaction to that law is that is(like the other Laws of Jim Crow) stupid and without sense, because each person have to choose who is going to marry with. And not to be forced to do things that a person doesn't want to do.

Jessie Daniels Ames

The chosen person's name is Jessie Daniels Ames. She was born in 1883 in Texas. She was Texas suffragist and civil-rights activist who fought against lynching in the South. Ames founded the Texas League of Women Voters. She recruited white Southern women to go out into the community and persuade law enforcement officials to sign a pledge that they would do everything in their power to protect their prisoners from being lynched. Jessie Daniels Ames was a very good woman who wanted to improve the life of the less fortunate people.

Rosewood, Florida

The racial turmoil chosen is the one occurred in Rosewood, Florida in 1922. In that small village were burnt down many African Americans. During the winter of 1922: the murder of a white schoolteacher in nearby Perry, led to the murder of three blacks, and a sexually assaulted of a black guy to a white girl, made the KKK angry. The Ku Klux Klan rallied in Gainesville on New Year's Eve. Then they burnt almost the entire village, excepting nine people, for the act of four. The things that happened in Rosewood were hideous, innocent people were killed without a motive. This event made open the eyes of a lot of white people of the atrocities that were being occurred.

Australian History in a few words

60,000 - 40,000 Before Christ

People from Southeast Asia settle in Australia, but it is not certain when people actually occupied the land mass.Their descendants are the Aboriginal people.

Boomerang

8000 B.C

Aborigines invented the boomerang(A bent or curved piece of tough wood used by the AustralianAborigines as a throwing club, one form of which can be thrown so as to return to the thrower)

1770 A.D
Britain claims Australia. It settles the first of six colonies in 1788.

Oro

1850
Gold is found in southern Australia. Entire settlements are deserted as folks rush to the gold mines.

1901
The six colonies join to form the Commonwealth of Australia. It has a democratic government. Britain's royalty has only a ceremonial role.

Camberra

1927
Canberra officially replaces Melbourne as the nation's capital.

1962
Aborigines are given the right to vote. Five years later, they're recognized as citizens.

1976
The Aboriginal Land Rights Act is passed. It is a legal turning point for Aborigines, giving them the right to make claims on their ancestral land in the Northern Territory. Nine years later, Uluru is returned to Aborigines.

Sydney 2000

2000
Sydney hosts the Summer Olympic Games.

2008
The Australian parliament formally apologizes for past wrongs committed against the Aboriginal people.

More Information:

TIME HISTORY

AUSTRALIA