Recursos para estudiantes de inglés de todos los niveles, profesores y traductores. Para aprender o mejorar tu inglés en forma divertida.
Listening Comprehension - Comprensión Auditiva

Cómo realizar este ejercicio de comprensión auditiva

- Siempre encontrarás una pequeña introducción, que puede ayudarte a comprender el tema tratado.

- En los textos presentados se han ocultado algunas palabras, que deberás escribir en los casilleros correspondientes. A medida que lees el texto, escucha el audio con atención para descubrir dichas palabras.

- Quizás puedes deducir las palabras sin necesidad de escuchar el audio. Pero, pon atención al audio para confirmar si realmente se trata de la respuesta correcta.

- Puedes escuchar el audio cuantas veces sea necesario. Pero es recomendable hacerlo solamente dos veces (o tres veces como máximo) ya que esa es la forma en que normalmente se realizan estos ejercicios en exámenes y pruebas internacionales.

- Comprueba tus aciertos pulsando el botón "Corregir". Si no has podido completar todas las palabras, pulsa el botón "Solución" para ver cuáles eran las que te faltaban.

Scientists Create Glue Inspired by Mussels
Topic: Have you ever wondered how those hard-shelled mollusks known as mussels anchor themselves to rocks on lake and river bottoms? How they stick to sea walls, or resist pounding waves? Scientists at the University of Chicago have done more than come up with some answers. They've actually created a synthetic gel that mimics the mussel's sticky, self-healing properties. Their invention could have far-reaching medical and industrial applications.
 Transcript of radio broadcast. Source: VOA

Listen to the audio clip and fill in the blanks.

Niels Holten-Anderson - a post-doctoral scholar at the University of Chicago - says mussels do two things really well. They excrete a sticky and they can use that natural glue to repair the anchoring bond.

Niels Holten-Anderson: "And the important thing to remember is that there are no cells. There is no live or living activity taking place inside these materials. The material is basically a dead material, just like our hair. So this capacity to re-heal itself is completely automatic, and it's not on any sort of energy input from living cells."

Holten-Anderson and colleagues at the University of Chicago, and a team of international scientists have worked on how to turn what mussels do naturally into a material. They zeroed in on the chemistry of what the mollusks secrete and discovered metal mixed inside their thin, hold-fast . Holten-Anderson says iron is a key ingredient that makes the adhesive strong and .

Niels Holten-Anderson: "The unique thing is you can pull them apart and if you leave them be, they can find their again and re-heal, and that's where the re-healing and its original strength comes from."

Holten-Anderson and colleagues set out to that in the laboratory using a synthetic polymer or a simplified version of a string of mussel protein molecules. They succeeded when they pre-mixed the polymer with metal at low pH.

Niels Holten-Anderson: "You instantly get an initiation of these self-healing strong gel-like, sticky materials as soon as you do this basically step-wise process of mixing things, and then increase the pH potentially what actually happens in the natural case anyway."

Iron is the metal available to mussels in the environment. Holten-Anderson says scientists can expand that and experiment with other metals.

Niels Holten-Anderson: "We've shown so far that a metal such as titanium, for example, which is interesting from the bio-medical side of things with materials and so forth, that we can actually use titanium atoms too to cross in these materials and those materials seem to have even stronger, or even higher strength than the iron based materials."

Holten-Anderson expects the nature-inspired material will have practical medical and uses. A patent is pending on how to make the gel, which is described online in the Proceedings of the National Academy of Sciences.

Score:
   

Más ejercicios similares: Nivel Principiantes - Nivel Intermedio - Nivel Avanzado

Libros recomendados (Ad)

Listening Power 1

Este es el primer libro de la serie, que explica las técnicas para mejorar la comprensión auditiva, cómo escuchar la idea principal e inferir detalles, cómo entender diálogos de películas, programas de radio y televisión. Ver más

Active Listening 1 Student's Book

Este libro contiene actividades para aprender a escuchar los detalles, aumentar el vocabulario, y a su vez mejorar la pronunciación. Contiene un CD de audio para practicar. Ver más

Clear Speech Student's Book

Este libro ayuda a los estudiantes a pronunciar y comprender correctamente el inglés americano. Con una presentación fácil de seguir, muchas ilustraciones y gran cantidad de ejercicios. Ver más

Bookstore
Libros gratis Practica inglés leyendo obras maestras de la literatura inglesa y norteamericana. Puedes obtener los libros gratis para descargar y leer en tu PC, tablet o ebook-reader. Visita la sección Free Books.

 

Vocabulary
Aprende o practica vocabulario de inglés con flashcards: divertidas fichas interactivas con imágenes.

 

That's curious!
Sandwich The word sandwich comes from the English diplomat John Montagu, 4th Earl of Sandwich. He was such a compulsive gambler that to avoid stopping the game to eat, he would order that this kind of food was brought to his table so as not to waste too much time.

Descubre el origen de las palabras en
The Story behind the Words

 

Recommended book (Ad)

Explicaciones en español. Incluye CD.

Comprar
Más libros similares

 

SaberInglés


 



As an Amazon Associate we earn from qualifying purchases.

© Copyright - Saber Inglés - 2000-2021
All rights reserved. Reproduction is prohibited.
Privacy Policy - Disclosure