National Academies urges renewed commitment to fusion

The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons.
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...

Commitment is the  process whereby stem cells:

Nursing organizations assume a significant role in consistently developing the nursing profession through education, research studies, establishing practice standards, and reforming health policies. Typically, nursing organizations operate at the regional, national, and international levels. For example, the International Council of Nurses (ICN) represents more than 28 million nurses worldwide. In contrast, the American Nurses Association (ANA) is a membership organization representing nurses...

Nursing organizations play a vital role in representing nurses working in specialized clinical settings, such as the American Association of Critical-Care Nurses (AACN).
The AACN emphasizes a healthy work environment through six standards to achieve an optimal patient outcome. The standards are appropriate staffing, meaningful recognition, collaboration, authentic leadership, effective communication, and decision-making. In addition, AACN provides certification programs, webinars, journals, and...

The intestinal epithelial lining rapidly renews every 4 to 5 days. The renewal is facilitated by intestinal stem cells (ISCs) located at the base of the crypt– a gland located at the bottom of each villus. ISCs divide asymmetrically to form new stem cells and progenitor daughter cells. The daughter cells are called transit-amplifying (TA) cells which move upwards along the crypt and either differentiate into absorptive cells– the enterocytes or secretory cells– including the...

After cellular or tissue damage, the resident stem cells present in the human body can locally repair and regenerate the damaged tissue or organ. However, even though some tissues do not have stem cells, they can repair and regenerate with the help of pre-existing cells. For example, beta cells of the pancreas and hepatocytes of the liver can divide to renew and regenerate the tissue. Here, both cell division and cell death are well regulated by homeostasis.
However, failure of such a system...