GRINDING AND CUTTING

Grinding and cutting reduce the size of solid materials by mechanical action, dividing them into smaller particles. Perhaps the most extensive application of grinding in the food industry is in the milling of grains to make flour, but it is used in many other processes, such as in the grinding of corn for manufacture of corn starch, the grinding of sugar and the milling of dried foods, such as vegetables.

Cutting is used to break down large pieces of food into smaller pieces suitable for further processing, such as in the preparation of meat for retail sales and in the preparation of processed meats and processed vegetables.

In the grinding process, materials are reduced in size by fracturing them. The mechanism of fracture is not fully understood, but in the process, the material is stressed by the action of mechanical moving parts in the grinding machine and initially the stress is absorbed internally by the material as strain energy. When the local strain energy exceeds a critical level, which is a function of the material, fracture occurs along lines of weakness and the stored energy is released. Some of the energy is taken up in the creation of new surface, but the greater part of it is dissipated as heat. Time also plays a part in the fracturing process and it appears that material will fracture at lower stress concentrations if these can be maintained for longer periods. Grinding is, therefore, achieved by mechanical stress followed by rupture and the energy required depends upon the hardness of the material and also upon the tendency of the material to crack - its friability.

The force applied may be compression, impact, or shear, and both the magnitude of the force and the time of application affect the extent of grinding achieved. For efficient grinding, the energy applied to the material should exceed, by as small a margin as possible, the minimum energy needed to rupture the material . Excess energy is lost as heat and this loss should be kept as low as practicable.
The important factors to be studied in the grinding process are the amount of energy used and the amount of new surface formed by grinding.

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Temporary Tattoos May Put You at Risk

Spring break is on the way, or maybe summer vacation. Time to pack your swim suit, hit the beach, and perhaps indulge in a little harmless fun. What about getting a temporary tattoo to mark the occasion? Who could it hurt to get a temporary tattoo?

It could hurt you, if you actually get one. Temporary tattoos typically last from three days to several weeks, depending on the product used for coloring and the condition of the skin. Unlike permanent tattoos, which are injected into the skin, temporary tattoos marketed as "henna" are applied to the skin's surface.

However, "just because a tattoo is temporary it doesn't mean that it is risk free," says Linda Katz, M.D., M.P.H., director of FDA's Office of Cosmetics and Colors. Some consumers report reactions that may be severe and long outlast the temporary tattoos themselves.

MedWatch, FDA's safety information and adverse event (bad side effects) reporting program, has received reports of serious and long-lasting reactions that consumers had not bargained for after getting temporary tattoos. Reported problems include redness, blisters, raised red weeping lesions, loss of pigmentation, increased sensitivity to sunlight, and even permanent scarring.

Some reactions have led people to seek medical care, including visits to hospital emergency rooms. Reactions may occur immediately after a person gets a temporary tattoo, or even up to two or three weeks later.

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Not Necessarily Safe

You may be familiar with henna, a reddish-brown coloring made from a flowering plant that grows in tropical and subtropical regions of Africa and Asia. Since the Bronze Age, people have used dried henna, ground into a paste, to dye skin, hair, fingernails, leather, silk and wool. This decoration—sometimes also known as mehndi—is still used today around the world to decorate the skin in cultural festivals and celebrations.

However, today so-called "black henna" is often used in place of traditional henna. Inks marketed as black henna may be a mix of henna with other ingredients, or may really be hair dye alone. The reason for adding other ingredients is to create a tattoo that is darker and longer lasting, but use of black henna is potentially harmful.

That's because the extra ingredient used to blacken henna is often a coal-tar hair dye containing p-phenylenediamine (PPD), an ingredient that can cause dangerous skin reactions in some people. Sometimes, the artist may use a PPD-containing hair dye alone. Either way, there's no telling who will be affected. By law, PPD is not permitted in cosmetics intended to be applied to the skin.

You may see "black henna" used in places such as temporary tattoo kiosks at beaches, boardwalks, and other holiday destinations, as well as in some ethnic or specialty shops. While states have jurisdiction over professional practices such as tattooing and cosmetology, that oversight differs from state to state. Some states have laws and regulations for temporary tattooing, while others don't. So, depending on where you are, it's possible no one is checking to make sure the artist is following safe practices or even knows what may be harmful to consumers.

A number of consumers have learned the risks the hard way, reporting significant bad reactions shortly after the application of black henna temporary tattoos.

• The parents of a 5-year-old girl reported that she developed severe reddening on her forearm about two weeks after receiving a black henna temporary tattoo. "What we thought would be a little harmless fun ended up becoming more like a nightmare for us," the father says. "My hope is that by telling people about our experience, I can help prevent this from happening to some other unsuspecting kids and parents."
• The mother of a 17-year-old girl agrees. "At first I was a little upset she got the tattoo without telling me," she says. "But when it became red and itchy and later began to blister and the blisters filled with fluid, I was beside myself." She explains that as a nurse, she's used to seeing all manner of injuries, "but when it's your own child, it's pretty scary," she says.
• And another mother, whose teenager had no reaction to red henna tattoos, describes the skin on her daughter's back as looking "the way a burn victim looks, all blistered and raw" after a black henna tattoo was applied there. She says that according to her daughter's doctor, the teenager will have scarring for life.

Hospital pharmacy

Hospital pharmacy

Pharmacies within hospitals differ considerably from community pharmacies. Some pharmacists in hospital pharmacies may have more complex clinical medication management issues whereas pharmacists in community pharmacies often have more complex business and customer relations issues.
Because of the complexity of medications including specific indications, effectiveness of treatment regimens, safety of medications (i.e., drug interactions) and patient compliance issues (in the hospital and at home) many pharmacists practicing in hospitals gain more education and training after pharmacy school through a pharmacy practice residency and sometimes followed by another residency in a specific area. Those pharmacists are often referred to as clinical pharmacists and they often specialize in various disciplines of pharmacy. For example, there are pharmacists who specialize in hematology/oncology, HIV/AIDS, infectious disease, critical care, emergency medicine, toxicology, nuclear pharmacy, pain management, psychiatry, anti-coagulation clinics, herbal medicine, neurology/epilepsy management, pediatrics, neonatal pharmacists and more.
Hospital pharmacies can often be found within the premises of the hospital. Hospital pharmacies usually stock a larger range of medications, including more specialized medications, than would be feasible in the community setting. Most hospital medications are unit-dose, or a single dose of medicine. Hospital pharmacists and trained pharmacy technicians compound sterile products for patients including total parenteral nutrition (TPN), and other medications given intravenously. This is a complex process that requires adequate training of personnel, quality assurance of products, and adequate facilities. Several hospital pharmacies have decided to outsource high risk preparations and some other compounding functions to companies who specialize in compounding. The high cost of medications and drug-related technology, combined with the potential impact of medications and pharmacy services on patient-care outcomes and patient safety, make it imperative that hospital pharmacies perform at the highest level possible.