Infants and children receiving artificial heart-valve replacements face several repeat operations as they grow, since the replacements become too small and must be traded for bigger ones.

Researchers at Children's Hospital Boston have now developed a solution: living, growing valves created in the lab from a patient's own cells.

Pulmonary valves, which provide one-way blood flow from the heart's right ventricle into the pulmonary artery, are often malformed in congenital heart disease, putting an extra burden on the heart.

Enzymes are proteins that act as catalysts in everything from single-celled organisms to humans. They promote chemical reactions in cells and are used widely in industry for everything from making beer and cheese to producing paper and biofuel.

They are also important for making 'natural' drugs, therapeutic agents based on the blueprints of chemicals produced in nature by plants and microorganisms. Such natural sugar-bearing chemicals are the basis for some of medicine's most potent antibiotics and anticancer drugs as exemplified by the antibiotic erythromycin and the anticancer drug doxorubicin.

Important chemical features of such drugs are natural sugars, molecules that often determine a chemical compound's biological effects.

If you look at a price and you see larger numbers on the far right, it makes a difference in how you perceive the discount compared to small numbers on the right even if the actual differences are the same, according to a new study from the Journal of Consumer Research.

So a price of $188 from an original price of $199 appears to be a better deal than a $222 price discounted to $211, even though they are both $11 cheaper.

However, if the left-most digit is small, people perceive they are getting a larger discount when the right digits are “small” -- less than 5 -- rather than when they are “large,” greater than 5.

For the past six weeks, parents have been able to keep a watchful eye over what they are feeding their children at mealtimes. However, with the back-to-school season fast approaching, most parents will once again face the constant dilemma of choosing which healthy, exciting, tasty and nutritious products they should give their children. Parents face the difficult choice of what to buy for their children as packaging can be misleading.

This report focuses on a selection of popular fruit juice drinks and fruit based desserts which can be found in a typical child's lunchbox.

FRUIT JUICE DRINKS

Fruit Juice Content

The tunic believed to have been worn by Saint Francis of Assisi preserved in the Church of Saint Francis in Cortona (Province of Arezzo) dates back to the period in which the saint lived, whereas the tunic preserved in the Church of Santa Croce in Florence was made after his death.

Carbon 14 measurements, which allow a relic to be dated, show that the tunic in Santa Croce dates back to some time between the late 13th century and late 14th century and thus could not have belonged to the “Poor Man of Assisi”, who died in 1226.

Autism spectrum disorders cover a wide span of conditions and symptoms, from severe mental retardation to mild social impairment. In general, people with autism have problems with social interactions, such as maintaining eye contact or reading body language. They may also exhibit stereotypical behavior, such as being obsessed with lining up objects. In the movie “Rain Man,” the title character was unable to form social bonds and became distressed when his normal routine was disrupted, yet he could perform exceptional mental mathematics.

About 1.5 million people in the United States have autism spectrum disorders, with boys affected more often than girls.