Lance Lafontaine's Blog

A molecular biology student's place for appreciation of the natural and health sciences, freethinking, technology and anything else that he deems remotely interesting.
Visit http://gravatar.com/lancelafontaine for more.

Lactose Intolerance.

What is lactose intolerance?

Lactose intolerance is the inability to digest and absorb lactose (the sugar in milk) that results in gastrointestinal symptoms when milk or food products containing milk are consumed.

What causes lactose intolerance?

Lactose is a large sugar molecule that is made up of two smaller sugars, glucose and galactose. In order for lactose to be absorbed from the intestine and into the body, it must first be split into glucose and galactose. The glucose and galactose are then absorbed by the cells lining the small intestine. The enzyme that splits lactose into glucose and galactose is called lactase, and it is located on the surface of the cells lining the small intestine.

Lactose intolerance is caused by reduced or absent activity of lactase that prevents the splitting of lactose (lactase deficiency). Lactase deficiency may occur for one of three reasons, congenital, secondary or developmental.

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Farthest Untethered Spacewalk
Mission Specialist Bruce McCandless II, is seen further away from the confines and safety of his ship than any previous astronaut has ever been. This space first was made possible by the Manned Manuevering Unit or MMU, a nitrogen jet propelled backpack. After a series of test maneuvers inside and above Challenger’s payload bay, McCandless went “free-flying” to a distance of 320 feet away from the Orbiter. This stunning orbital panorama view shows McCandless out there amongst the black and blue of Earth and space.

Farthest Untethered Spacewalk

Mission Specialist Bruce McCandless II, is seen further away from the confines and safety of his ship than any previous astronaut has ever been. This space first was made possible by the Manned Manuevering Unit or MMU, a nitrogen jet propelled backpack. After a series of test maneuvers inside and above Challenger’s payload bay, McCandless went “free-flying” to a distance of 320 feet away from the Orbiter. This stunning orbital panorama view shows McCandless out there amongst the black and blue of Earth and space.

(via blamoscience)

Snippets of RNA Can Help Fight TumorsUsing a technique known as “nucleic acid origami,” chemical engineers have built tiny particles made out of DNA and RNA that can deliver snippets of RNA directly to tumors, turning off genes expressed in cancer cells.To achieve this type of gene shutdown, known as RNA interference, many researchers have tried — with some success — to deliver RNA with particles made from polymers or lipids. However, those materials can pose safety risks and are difficult to target, says Daniel Anderson, an associate professor of health sciences and technology and chemical engineering.Read more: http://www.laboratoryequipment.com/news-Snippets-of-RNA-Could-Fight-Tumors-060512.aspx

Snippets of RNA Can Help Fight Tumors

Using a technique known as “nucleic acid origami,” chemical engineers have built tiny particles made out of DNA and RNA that can deliver snippets of RNA directly to tumors, turning off genes expressed in cancer cells.

To achieve this type of gene shutdown, known as RNA interference, many researchers have tried — with some success — to deliver RNA with particles made from polymers or lipids. However, those materials can pose safety risks and are difficult to target, says Daniel Anderson, an associate professor of health sciences and technology and chemical engineering.

Read more: http://www.laboratoryequipment.com/news-Snippets-of-RNA-Could-Fight-Tumors-060512.aspx

(Source: laboratoryequipment, via scinerds)

Milky Way Galaxy Doomed: Collision with Andromeda Pending
Illustration Credit: NASA, ESA, Z. Levay and R. van der Marel (STScI), and A. Mellinger
Will our Milky Way Galaxy collide one day with its larger neighbor, the Andromeda Galaxy?
Most likely, yes. Careful plotting of slight displacements of M31’s stars relative to background galaxies on recent Hubble Space Telescope images indicate that the center of M31 could be on a direct collision course with the center of our home galaxy.
Still, the errors in sideways velocity appear sufficiently large to admit a good chance that the central parts of the two galaxies will miss, slightly, but will become close enough for their outer halos to become gravitationally entangled. Once that happens, the two galaxies will become bound, dance around, and eventually merge to become one large elliptical galaxy — over the next few billion years.
Pictured above is an artist’s illustration of the sky of a world in the distant future when the central parts of each galaxy begin to destroy each other. The exact future of our Milky Way and the entire surrounding Local Group of Galaxies is likely to remain an active topic of research for years to come.

Milky Way Galaxy Doomed: Collision with Andromeda Pending

Illustration Credit: NASA, ESA, Z. Levay and R. van der Marel (STScI), and A. Mellinger

Will our Milky Way Galaxy collide one day with its larger neighbor, the Andromeda Galaxy?

Most likely, yes. Careful plotting of slight displacements of M31’s stars relative to background galaxies on recent Hubble Space Telescope images indicate that the center of M31 could be on a direct collision course with the center of our home galaxy.

Still, the errors in sideways velocity appear sufficiently large to admit a good chance that the central parts of the two galaxies will miss, slightly, but will become close enough for their outer halos to become gravitationally entangled. Once that happens, the two galaxies will become bound, dance around, and eventually merge to become one large elliptical galaxy — over the next few billion years.

Pictured above is an artist’s illustration of the sky of a world in the distant future when the central parts of each galaxy begin to destroy each other. The exact future of our Milky Way and the entire surrounding Local Group of Galaxies is likely to remain an active topic of research for years to come.

(Source: afro-dominicano, via princeofmayfair)

Two More Elements Added to The Periodic Table
You can now greet by name two new residents of the period table of elements: Flerovium and Livermorium.
The International Union of Pure and Applied Chemistry officially approved names for the elements — which sit at slot 114 and 116, respectively — on 31 May. They have until now gone by the temporary monikers ununquadium and ununhexium.

Two More Elements Added to The Periodic Table

You can now greet by name two new residents of the period table of elements: Flerovium and Livermorium.

The International Union of Pure and Applied Chemistry officially approved names for the elements — which sit at slot 114 and 116, respectively — on 31 May. They have until now gone by the temporary monikers ununquadium and ununhexium.

(via holymoleculesbatman)

medicalstate:

Unilateral Dermatoheliosis.
This stunning image of a 69 year old shows the effects of sun exposure on premature aging of skin. The man was a truck driver for 28 years during which the sun predominantly shined onto his face through his left window.

medicalstate:

Unilateral Dermatoheliosis.

This stunning image of a 69 year old shows the effects of sun exposure on premature aging of skin. The man was a truck driver for 28 years during which the sun predominantly shined onto his face through his left window.

Chemistry: What's inside neutrons and protons?

The neutrons and protons consist of three elementary particles called quarks.

The types of quarks inside the neutron are called up and down quarks. The difference between them is in the mass and in the charge. The up quark has a charge +2/3 and the down quark (-1/3).

The neutron is electricly neutral (which is the reason for its name), so its total charge is 0. Threfore to only way for it to have a zero total charge is when it is build of one Up quark and two Dawn quarks. 

Up + Down + Down = Neutron;
2/3 - 1/3 - 1/3 = 0 

Protons have three quarks too. Protons have charge +1, therefore

Up + Up + Down = Proton 

(via shychemist)

holymoleculesbatman:

Fascinating and complicated: Lignin
(C9H10O2, C10H12O3, C11H14O4) 
Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. It is one of the most abundant organic polymers on Earth, exceeded only by cellulose, employing 30% of non-fossil organic carbon, and constituting from a quarter to a third of the dry mass of wood.  

holymoleculesbatman:

Fascinating and complicated: Lignin

(C9H10O2, C10H12O3, C11H14O4

Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. It is one of the most abundant organic polymers on Earth, exceeded only by cellulose, employing 30% of non-fossil organic carbon, and constituting from a quarter to a third of the dry mass of wood.