Senescence.

http://en.wikipedia.org/wiki/Red_blood_cell

The aging erythrocyte undergoes changes in its plasma membrane, making it susceptible to selective recognition by macrophages and subsequent phagocytosis in the mononuclear phagocyte system (spleen, liver and lymph nodes), thus removing old and defective cells and continually purging the blood. This process is termed eryptosis, erythrocyte programmed cell death.This process normally occurs at the same rate of production by erythropoiesis, balancing the total circulating red blood cell count. Eryptosis is increased in a wide variety of diseases including sepsis, haemolytic uremic syndrome, malaria, sickle cell anemia, beta-thalassemia,glucose-6-phosphate dehydrogenase deficiency, phosphate depletion, iron deficiency and Wilson's disease. Eryptosis can be elicited by osmotic shock, oxidative stress, energy depletion as well as a wide variety of endogenous mediators and xenobiotics. Excessive eryptosis is observed in erythrocytes lacking the cGMP-dependent protein kinase type I or the AMP-activated protein kinase AMPK. Inhibitors of eryptosis include erythropoietin, nitric oxide, catecholamines and high concentrations of urea.

Much of the resulting breakdown products are recirculated in the body. The heme constituent of hemoglobin are broken down into Fe³⁺ and biliverdin. The biliverdin is reduced to bilirubin, which is released into the plasma and recirculated to the liver bound to albumin. The iron is released into the plasma to be recirculated by a carrier protein called transferrin. Almost all erythrocytes are removed in this manner from the circulation before they are old enough to hemolyze. Hemolyzed hemoglobin is bound to a protein in plasma called haptoglobin, which is not excreted by the kidney.

Erythropoiesis.

http://en.wikipedia.org/wiki/Red_blood_cell

Erythropoiesis is the development process by which new erythrocytes are produced; it lasts about 7 days. Through this process erythrocytes are continuously produced in the red bone marrow of large bones, at a rate of about 2 million per second in a healthy adult. (In the embryo, the liver is the main site of red blood cell production.) The production can be stimulated by thehormone erythropoietin (EPO), synthesised by the kidney. Just before and after leaving the bone marrow, the developing cells are known as reticulocytes; these comprise about 1% of circulating red blood cells.

Life Cycle of Erythrocytes.

http://en.wikipedia.org/wiki/Red_blood_cell

Human erythrocytes are produced through a process named erythropoiesis, developing from committed stem cells to mature erythrocytes in about 7 days. 

When matured, in a healthy individual these cells live in blood circulation for about 100 to 120 days (and 80 to 90 days in a full term infant).At the end of their lifespan, they become senescent, and are removed from circulation. In many chronic diseases, the lifespan of the erythrocytes is markedly reduced (e.g. patients requiring haemodialysis).

Protein Biosynthesis in Red Blood Cells.

http://en.wikipedia.org/wiki/Red_blood_cell

As red blood cells contain no nucleus, protein biosynthesis is currently assumed to be absent in these cells, although a recent study indicates the presence of all the necessary biomachinery in the cells to do so.

The blood's red color is due to the spectral properties of the hemic iron ions in hemoglobin. Each human red blood cell contains approximately 270 million of these hemoglobin biomolecules, each carrying four heme groups; hemoglobin comprises about a third of the total cell volume. This protein is responsible for the transport of more than 98% of the oxygen (the remaining oxygen is carried dissolved in the blood plasma). The red blood cells of an average adult human male store collectively about 2.5 grams of iron, representing about 65% of the total iron contained in the body.

Human Erythrocytes.

http://en.wikipedia.org/wiki/Red_blood_cell

A typical human erythrocyte has a disk diameter of approximately 6.2–8.2 µm and a thickness at the thickest point of 2–2.5 µm and a minimum thickness in the centre of 0.8–1 µm, being much smaller than most other human cells. These cells have an average volume of about 90 fL with a surface of about 136 μm², and can swell up to a sphere shape containing 150 fL, without membrane distension.

Adult humans have roughly 2–3 × 10¹³ (20–30 trillion) red blood cells at any given time, comprising approximately one quarter of the total human body cell number (women have about 4 to 5 million erythrocytes per microliter (cubic millimeter) of blood and men about 5 to 6 million; people living at high altitudes with low oxygen tension will have more). 

Red blood cells are thus much more common than the other blood particles: there are about 4,000–11,000 white blood cells and about 150,000–400,000 platelets in each microliter of human blood.

Human red blood cells take on average 20 seconds to complete one cycle of circulation.

What Keeps the Global Business Elite Up at Night?

http://www.bloomberg.com/native/article/?mvi=7704927711a54a8f985c677e35cf436f

                                             Environmental risk continues to top the list in 2014.

Ukraine to Extend Cease-Fire as President Signs EU Pact.

http://www.bloomberg.com/news/2014-06-27/ukraine-to-extend-cease-fire-as-president-signs-eu-pact.html

Ukraine will extend a cease-fire in its fight against separatist rebels today after President Petro Poroshenko signed a European Union accord rejected by his predecessor that sent the country spiraling into crisis.

The government in Kiev will prolong the week-long truce, which it says has been repeatedly flouted by pro-Russian separatists, by 72 hours from an original plan to end it at 10 p.m. tonight, two European government officials said. The officials asked not to be named because the discussions were private and hadn’t finished. The extension will let talks continue on the release of hostages held by separatists in Ukraine’s eastern border regions, one official said.

Earlier, Poroshenko signed a free-trade pact with the 28-member EU at a summit in Brussels, while EU heads of government also prepared to discuss possible new sanctions against Russia. Poroshenko said that by signing the deal, Ukraine is underlining “its sovereign choice in favor of future membership of the EU.”