Increase in black lung disease sparks new rules for coal mines
New regulations mark the first significant chances in coal dust policy since 1969.
As you can see, the arachnoid membrane contains a lot of venes laying on top of brain’s surface (cortex) in order to guarantee a good blood circulation in the brain region. Also, it plays a large role for the cerebrospinal fluid.
Cerebrospinal fluid circulates in the subarachnoid space (between arachnoid and pia mater). It is produced by the choroid plexus (inside the ventricles of the brain, which are in direct communication with the subarachnoid space so the fluid can flow freely through the nervous system).
Cerebrospinal fluid is a transparent, colourless fluid and it is produced at about 500 ml/day. Its electrolyte levels, glucose levels, and pH are very similar to those in plasma, but the presence of blood in cerebrospinal fluid is always abnormal.
The arachnoid mater is named after the Greek words “Arachne” (“spider”) and suffix “-oid” (“in the image of”), and “mater” (the Latin word for mother), because of the fine spider web-like appearance of the delicate fibres of the arachnoid which extend down through the subarachnoid space and attach to the pia mater.
Image found on mr-friendly-awesomesauce.tumblr.com (if you go to this page, there are NSFW photos)
What you can see here is a resin cast of pancreatic blood vessels. The fine network of smaller vessels that branches off from the main vessels infiltrates the tissue, supplying it with blood. Gases and nutrients are exchanged between the blood and surrounding tissues through the permeable walls of capillaries, the smallest blood vessels.
The pancreas produces the hormones insulin and glucagon, which regulate blood glucose levels. It also secretes digestive enzymes. The cast was made by injecting resin into the blood vessels, followed by chemical digestion of surrounding tissues.
Even on this microscopic image with 30x magnification, the network of blood vessels is sheer endless, our body is a miracle of architectural compactness
Image by Susumu Nishinaga
How to: Improve your Memory
Nearly everyone wants a better memory, or could just use a better memory. To just be able to remember the last item on a shopping list, or where they put their car keys. But most importantly, remember all the information for exams. This video has tips and tricks to improving your memory in all kinds of ways.
Impressive example of Pneumococcal meningitis!
Meningitis is a clinical syndrome characterized by inflammation of the meninges, the 3 layers of membranes that enclose the brain and spinal cord. These layers consist of the following:
Dura - A tough outer membrane
Arachnoid - A lacy, weblike middle membrane
Subarachnoid space - A delicate, fibrous inner layer that contains many of the blood vessels that feed the brain and spinal cord
The inflammation may be caused by infection with viruses, bacteria, or other microorganisms.
Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.
Pneumococcal meningitis occurs when the bacteria that have invaded the bloodstream move across to infect the meninges.
The meninges are filled with a liquid called cerebrospinal fluid (CSF), which is there to bathe the brain and cushion it against physical damage.
Bacteria can multiply freely in CSF, and there they release poisons, causing inflammation and swelling in the meninges and the brain tissue itself.
This increases pressure on the brain, producing symptoms of meningitis such as headache, stiff neck and dislike of bright lights.
Risk factors: -Extremes of age (< 5 or >60 years)
-Diabetes mellitus, renal or adrenal insufficiency, hypoparathyroidism, or cystic fibrosis
-Splenectomy and sickle cell disease
-Alcoholism and cirrhosis
-Recent exposure to others with meningitis
-Contiguous infection (eg, sinusitis)
-Intravenous (IV) drug abuse
-Some cranial congenital deformities
Read more: www.bit.ly/1j1XDUQ
Photo credits: Dr. Edwin P. Ewing, Jr.
This pair of images shows, on top, a modern-day leafcutter bee from the species Megachile rotundata and a very cool fossil find from the LaBrea Tar Pits.
The bees come from a pair of full nests exhumed from a part of the tar pits; the same location has produced bones from animals 23,000 to 40,000 years old, and carbon-14 dating of the material in the nests gives the same age, so these bees are about that old. Many interesting specimens are preserved in the nests and have been found by scientists exhuming material from the tar pits, including the leafy walls of the nests themselves, adults, and pupae like this one.
The bees are from species that are widespread in the United States, but the presence of these bees at this site actually helps constrain how their distributions have changed during the big climate shifts that happened since the nests were made. The bees today have expanded ranges at higher elevations than is suggested by these fossil finds, indicating that as the climate of the area warmed, the bees moved uphill to follow similar temperature levels.
Image credit: PLOS One (Open access journal):