Depending on how acting filters can be physical or chemical.

• Physical filters: are substances impervious to sunlight, creating a screen in areas where it has been applied and reflects light. Prevent the passage of the three types of radiation: ultraviolet, visible and infrared. The most commonly used are zinc oxide, titanium dioxide and mica.
• Chemical filters: they absorb solar ultraviolet radiation. Some of those used are the PABA (para-amino benzoic acid), cinnamic acid, sulfonic acid, camphor, benzophenone and dibenzoylmethanes.

To quantify the filtering capacity of sunscreen is used the so-called Sun Protection Factor: a number that measures how many times it can be exposed to the sun to produce the same redness or erythema that if he had not used the cream sunscreen. That is, if not for the skin starts to turn red (erythema), the first day that we must take the sun 10 minutes, using an SPF cream 5, it will take 50 minutes.

The SPF indicates the time that we expose to the sun without risk of burns. The higher the SPF, the higher the protection from sunlight.

Sunlight breaks down upon reaching the earth’s surface in various types of radiation according to wavelength, are classified as ultraviolet radiation, visible radiation and infrared. In turn, ultraviolet radiation can be UVC, UVB or UVA. UVC rays have the shortest wavelength, are the most energy and therefore more capable of burns, but are retained by the ozone layer. Thus the reduction or the existence of holes in the ozone layer is so dangerous.

UVB rays as well as the heating effect (which causes the redness or Erythema of the skin when exposed to sunlight), penetrate the epidermis and stimulate the melanocytes (skin cells that produce melanin, the substance that gives the brown color to the skin).

UVA rays are the most penetrating the skin and are the cause of skin aging and melanoma (skin cancer).

Besides the type of radiation, it is necessary to know the factors influencing the action of sunlight on the skin. Thus, we must bear in mind that, how much higher the geographical area where we are, the more intense the exposure, the obliquity of the rays of the sun and the earth also influences, depending on the season, time of day and the latitude of the geographical area. The climate also influences, as the rain and clouds absorb some radiation. Also the type of area where we are, because the snow reflects up to 85% of the rays, and the dry sand to 17%.

To guard against such harmful effects, the human skin with the production of melanin, a substance that prevents most harmful solar radiation to penetrate the skin. Melanin is what gives the dark color to the skin and its production is stimulated by the effect of sunlight or chemicals. The number of cells that produce this substance varies according to skin types. People is highest in blacks, and lowest in whites, and among them, the lighter skins are the most susceptible to the effects of the sun.

The best thing to do is to keep all your prenatal care visits. One of the things your doctor will monitor the size of your abdomen and the amniotic fluid that is inside the uterus. If you experience a problem, your doctor will take steps to avoid further complications for you and your baby.

If you have diabetes, talk with your health professional about their increased risk for polyhydramnios.

If your doctor,  suspects you have polyhydramnios, you may need additional testing and monitoring throughout their pregnancy. In half the cases, polyhydramnios goes away without treatment. In other cases, the problem can be corrected when the cause is found. For example, treat high blood sugar in women with diabetes often decreases the amount of amniotic fluid. Other treatments may include removing some amniotic fluid or use medication to reduce fluid levels.

When a woman has polyhydramnios, means that the level of amniotic fluid surrounding the baby is very high. To understand how this condition can affect your health and your baby can help you learn about the role that amniotic fluid plays in a healthy pregnancy.

What you should know about the amniotic fluid

The amniotic fluid surrounding the fetus’s body plays an important role in normal development. This translucent liquid surrounds and protects the fetus and provides fluid. During the second trimester, the fetus is able to breathe the fluid, so that it enters your lungs, and swallowing, promoting normal growth and development of the lungs and gastrointestinal system. The amniotic fluid also allows the fetus move, which helps in the normal development of muscles and bones.

The amniotic sac containing the embryo is formed around 12 days after conception. Amniotic fluid begins to fill the bag immediately. During the first weeks of pregnancy, amniotic fluid consists mainly of water supplied by the mother. After about 12 weeks, the fluid is composed mainly of fetal urine. The amount of amniotic fluid increases until about week 28 to 32 of pregnancy, when measuring a little less than a quart. After that time, the liquid level usually remains stable until the fetus reaches full development (between 37 and 40 weeks), when it starts to decrease.

About 2 of every 100 pregnant women had polyhydramnios (too much amniotic fluid). Most cases are mild and are the product of a gradual accumulation of fluid in the second half of pregnancy. Approximately half of the cases, polyhydramnios goes away by itself. But some cases begin as early as 16 weeks of pregnancy and often result in very early delivery. Polyhydramnios is diagnosed by ultrasound. Medical experts still do not know for sure the causes of this condition. The cause in 2 out of 3 cases. Known causes are:

• Birth defects in the baby that affect the ability to swallow. Normally, when a fetus swallows amniotic fluid level decreases slightly. This helps balance the increased fluid when the fetus urinates.
• Heart defects in the baby

Women with diabetes are at increased risk for polyhydramnios, but seem to have fewer complications from it than non-diabetic. Women with mild polyhydramnios have few symptoms. Women with polyhydramnios may have more serious discomfort in the stomach and breathing problems, because the increased fluid causes the uterus invades the space of the lungs and organs of the belly.
Polyhydramnios may increase the risk of complications during pregnancy, including:

* Premature rupture of membranes (tear or rupture of the sac containing the amniotic fluid)
* Prematurity
* The umbilical cord accidents
* The placental
* Little baby’s growth
* The stillbirth
* Cesarean delivery
* Severe bleeding in the mother after delivery.

Ignatz von Peczely (1826 – 1911) His experience with iridology began with the breaking of the leg of an owl trying to free it from a bush. When caring, observed the emergence of a black mark on your iris, at six o’clock. Then, during his recovery, he noted that the signal is cleared. On this thin evidence, was then studying Decic eyes of their patients, while working as a homeopath and, later, to graduate as a doctor. His profession would have given him the opportunity to relate their findings in patients studied before and after surgery, in addition to the many who performed autopsies.

Von Peczely produced one of the first European iris image linked to modern revival of this technique.

Iridology (also called iridodiagnósis or iris diagnosis) is a diagnostic alternative medicine whose creators believe that the conformation, color and other characteristics of the iris can be examined for information on patient health.

Its practitioners relate their observations to iris charts about dividing it into areas that correspond to specific areas of the human body. The iridiólogos eye sees as “windows” through which you can see the functional status and health of the patient. Seasoned iridologists graphics used to emphasize what systems and body parts are healthy and which are overactive, inflamed or sore. Professionals use this information to establish the patient’s propensity toward certain diseases, to confirm former health problems, or to predict future health problems that may be brewing.

As there is a treatment, practitioners of this technique often study and practice other specialties of alternative medicine such as naturopathy, homeopathy, acupuncture, etc. Or are doctors who apply conventional treatments based on the diagnosis iridologist.