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# bone mass percentage chart

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Pie chart

A pie chart (or a circle graph) is a circularchart divided into sectors, illustrating proportion. In a pie chart, the arc length of each sector (and consequently its central angle and area), is proportional to the quantity it represents. When angles are measured with 1 turn as unit then a number of percent is identified with the same number of centiturns. Together, the sectors create a full disk. It is named for its resemblance to a pie which has been sliced. The earliest known pie chart is generally credited to William Playfair's Statistical Breviary of 1801.

The pie chart is perhaps the most ubiquitous statistical chart in the business world and the mass media. However, it has been criticized, and some recommend avoiding it, pointing out in particular that it is difficult to compare different sections of a given pie chart, or to compare data across different pie charts. Pie charts can be an effective way of displaying information in some cases, in particular if the intent is to compare the size of a slice with the whole pie, rather than comparing the slices among them. Pie charts work particularly well when the slices represent 25 to 50% of the data, but in general, other plots such as the bar chart or the dot plot, or non-graphical methods such as tables, may be more adapted for representing certain information.It also shows the frequency within certain groups of information.

## Example

The following example chart is based on preliminary results of the election for the European Parliament in 2004. The table lists the number of seats allocated to each party group, along with the derived percentage of the total that they each make up. The values in the last column, the derived central angle of each sector, is found by multiplying the percentage by 360Â°.

*Because of rounding, these totals do not add up to 100 and 360.

The size of each central angle is proportional to the size of the corresponding quantity, here the number of seats. Since the sum of the central angles has to be 360Â°, the central angle for a quantity that is a fraction Q of the total is 360Q degrees. In the example, the central angle for the largest group (European People's Party (EPP)) is 135.7Â° because 0.377 times 360, rounded to one decimal place(s), equals 135.7.

## Use, effectiveness and visual perception

Pie charts are common in business and journalism, perhaps because they are perceived as being less "geeky" than other types of graph. However statisticians generally regard pie charts as a poor method of displaying information, and they are uncommon in scientific literature. One reason is that it is more difficult for comparisons to be made between the size of items in a chart when area is used instead of length and when different items are shown as different shapes. Stevens' power law states that visual area is perceived with a power of 0.7, compared to a power of 1.0 for length. This suggests that length is a better scale to use, since perceived differences would be linearly related to actual differences.

Further, in research performed at AT&T Bell Laboratories, it was shown that comparison by angle was less accurate than comparison by length. This can be illustrated with the diagram to the right, showing three pie charts, and, below each of them, the corresponding bar chart representing the same data. Most subjects have difficulty ordering the slices in the pie chart by size; when the bar chart is used the comparison is much easier.. Similarly, comparisons between data sets are easier using the bar chart. However, if the goal is to compare a given category (a slice of the pie) with the total (the whole pie) in a single chart and the multiple is close to 25 or 50 percent, then a pie chart can often be more effective than a bar graph.

## Variants and similar charts

### Polar area diagram

The polar area diagram is similar to a usual pie chart, except sectors are equal angles and differ rather in how far each sector extends from the center of the circle. The polar area diagram is used to plot cyclic phenomena (e.g., count of deaths by month). For example, if the count of deaths in each month for a year are to be plotted then there will be 12 sectors (one per month) all with the same angle of 30 degrees each. The radius of each sector would be proportional to the square root of the death count for the month, so the area of a sector represents the number of deaths in a month. If the death count in each month is subdivided by cause of death, it is possible to make multiple comparisons on one diagram, as is clearly seen in the form of polar area diagram famously developed by Florence Nightingale.

The first known use of polar area diagrams was by AndrÃ©-Michel Guerry, which he called courbes circulaires, in an 1829 paper showing seasonal and daily variation in wind direction over the year and births and deaths by hour of the day. LÃ©on Lalanne later used a polar diagram to show the frequency of wind directions around compass points in 1843. The wind rose is still used by meteorologists. Nightingale published her rose diagram in 1858. The name "coxcomb" is sometimes used erroneously. This was the name Nightingale used to refer to a book containing the diagrams rather than the diagrams themselves. It has been suggested that most of Nightingale's early reputation was built on her ability to give clear and concise presentations of data.

### Spie chart

A useful variant of the polar area chart is the spie chart designed by Feitelson . This superimposes a normal pie chart with a modified polar area chart to permit the comparison of a set of data at two different states. For the first state, for example time 1, a normal pie chart is drawn. For the second state, the angles of the slices are the same as in the original pie chart, and the radii vary according to the change in the value of each variable. In addition to comparing a partition at two times (e.g. this year's budget distribution with last year's budget distribution), this is useful for visualizing hazards for population groups (e.g. the distribution of age and gener groups among road casualties compared with these groups's sizes in the general population). The R Graph Gallery provides an example.

### Multi-level pie chart

Multi-level pie chart, also known as a radial tree c

Active rock

Active rock is a radio format used by many commercial radio stations across Canada and the United States. Active rock plays current rock artists with a mix of classic rock songs.

## Format background

An active rock station may include songs by "classic" artists in its playlist, whereas a modern rock station would not. Conversely, unlike classic rock stations, an active rock station also plays music by popular current and new rock artists.

Similar to active rock stations, mainstream rock stations play current rock music, but concentrate more on classic rock than active rock stations do.

A pioneering station of this format in the late 1980s was WIYY "98Rock" in Baltimore, Maryland. Other early adopters of this format by the beginning of the 1990s include stations KISS "99.5 KISS Rocks" in San Antonio, TX, WAAF in Boston, Massachusetts, WXTB "98Rock" in Tampa, Florida, WGIR (FM) "Rock 101" in Manchester, New Hampshire and KEGL, "97.1 The Eagle ", in Dallas/Fort Worth, Texas. Satellite radio channels include Sirius XM Radio's Octane, and the gold-basedBone Yard channel, also on Sirius XM Radio. Former counterparts prior to the November 12, 2008 Sirius/XM channel merger were XM'sSquizz and Sirius'sBuzzSaw. Australian radio network Triple M Network also uses this format. A later Internet radio station, [http://frogboxradio.net Frogbox Radio], also began playing an Active rock format.

Active rock stations in Canada also include CFBR-FM in Edmonton, CHTZ-FM in St. Catharines and CJKR-FM in Winnipeg.

## Active Rock Airplay chart

Active Rock Airplay Chart is a chart that compiles the current hits on Active Rock radio stations and is used as a component for the Billboard Mainstream Rock chart. This chart is exclusive to R&R, with forty positions on this chart and it is solely based on radio airplay. 62 Active Rock radio stations are electronically monitored 24 hours a day, seven days a week by Nielsen Broadcast Data Systems. Songs are ranked by a calculation of the total number of spins per week with its "audience impression", which is based upon exact times of airplay and each station's Arbitron listener data.

Songs receiving the greatest growth will receive a "bullet", although there are tracks that will also get bullets if the loss in detections doesn't exceed the percentage of downtime from a monitored station. "Airpower" awards are issued to songs that appear on the top 20 of both the airplay and audience chart for the first time, while the "greatest gainer" award is given to song with the largest increase in detections. A song with six or more spins in its first week is awarded an "airplay add". If a song is tied for the most spins in the same week, the one with the biggest increase that previous week will rank higher, but if both songs show the same amount of spins regardless of detection the song that is being played at more stations is ranked higher. Songs that fall below the top 20 and have been on the chart after 20 weeks are removed and go to recurrent status.

Body shape

Human body shape is a complex phenomenon with sophisticated detail and function. The general shape or figure of a person is defined mainly by skeletal structure, muscles and fat. Skeletal structure grows and changes only up to the point at which a human reaches adulthood and remains essentially the same for rest of his or her life.

During puberty, differentiation of the male and female body occurs for the purposes of reproduction. In adult humans, muscle mass may change due to exercise, and fat distribution may change due to hormone fluctuations. Inherited genes play a large part in the development of body shape.

Body shape has effects on body posture and gait, and has a major role in physical attraction. This is because a body's shape implies an individual's hormone levels during puberty, which implies fertility, and it also indicates current levels of sex hormones. A pleasing shape also implies good health and fitness of the body. The art of figure drawing defines body proportions that are considered ideal.

## Skeletal structure

Skeletal structure frames the overall shape of the body and does not alter much over a lifetime. Males are generally taller, but body shape may be analyzed after normalizing with respect to height.

Broad shoulders and expanded chest (in males):
Widening of the shoulders occurs as part of the male pubertal process. Expansion of the ribcage is caused by the effects of testosterone during puberty. Hence males generally have broad shoulders and expanded chests, allowing them to inhale more air to supply their muscles with oxygen.
Wide hips (in females):
Widening of the hip bones occurs as part of the female pubertal process, and estrogen (the predominant sex hormone in females) causes a widening of the pelvis as a part of sexual differentiation. Hence females generally have wider hips, permitting childbirth. Because the female pelvis is flatter, more rounded and proportionally larger, the head of the fetus may pass during childbirth. The sacrum in females is shorter and wider, and also directed more toward the rear (see image). This affects their walking style, resulting in hip sway; also, females generally stand with hips relaxed to one side.

After puberty, female hips are generally wider than female shoulders; males exhibit the opposite configuration. But not everyone follows this stereotypical pattern of secondary sex characteristics. Both male and female hormones are present in the human body, and though only one of them is predominant in an adult, the other hormone has effects on body's shape to some extent.

### Facial features

Due to the action of testosterone, males develop these facial-bone features during puberty:

• A more prominent brow bone.
• A heavier jaw.
• More prominent chin.
• Larger nose bone.

Because females have around 20 times less testosterone, these features do not develop to the same extent. Hence female faces are generally more similar to those of pre-pubertal children.

## Fat distribution, muscles and tissues

Body shape is affected by body fat distribution, which is correlated to current levels of sex hormones. Muscles and fat distribution may change from time to time, unlike bone structure, depending on food habits, exercises and hormone levels.

### Fat distribution

Estrogen causes fat to be stored in the buttocks, thighs, and hips in women. When women reach menopause and the oestrogen produced by ovaries declines, fat migrates from their buttocks, hips and thighs to their waists; later fat is stored in the belly. Thus females generally have relatively narrow waists and large buttocks, and this along with wide hips make for a wider hip section and a lower waist-hip ratio compared to men.

Estrogen increases fat storage in the body, which results in more fat stored in the female body. Body fat percentage recommendations are higher for females, as this may serve as an energy reserve for pregnancy. Males have less subcutaneous fat in their faces due to the effects of testosterone; testosterone also reduces fat by aiding fat metabolism. Males generally deposit fat around waists and nonlinearcurrentâ€“voltage characteristic. The name is a portmanteau of variable resistor. Varistors are often used to protectcircuits against excessive transient voltages by incorporating them into the circuit in such a way that, when triggered, they will shunt the current created by the high voltage away from the sensitive components. A varistor is also known as Voltage Dependent Resistor or VDR. A varistorâ€™s function is to conduct significantly increased current when voltage is excessive.

Note: only non-ohmic variable resistors are usually called varistors. Other, ohmic types of variable resistor include thepotentiometer and the rheostat.

## Metal oxide varistor

The most common type of varistor is the Metal Oxide Varistor (MOV). This contains a ceramic mass of zinc oxide grains, in a matrix of other metal oxides (such as small amounts of bismuth, cobalt, manganese) sandwiched between two metal plates (the electrodes). The boundary between each grain and its neighbour forms a diode junction, which allows current to flow in only one direction. The mass of randomly oriented grains is electrically equivalent to a network of back-to-back diode pairs, each pair in parallel with many other pairs. When a small or moderate voltage is applied across the electrodes, only a tiny current flows, caused by reverse leakage through the diode junctions. When a large voltage is applied, the diode junction breaks down due to a combination of thermionic emission and electron tunneling, and a large current flows. The result of this behavior is a highly nonlinear current-voltage characteristic, in which the MOV has a high resistance at low voltages and a low resistance at high voltages.

Follow-through current as a result of a lightning strike may generate excessive current that permanently damages a varistor. In general, the primary case of varistor breakdown is localized heating caused as an effect of thermal runaway. This is due to a lack of conformality in individual grain-boundary junctions, which leads to the failure of dominant current paths under thermal stress.

Varistors can absorb part of a surge. How much effect this has on risk to connected equipment depends on the equipment and details of the selected varistor. Varistors do not absorb a significant percentage of a lightning strike, as energy that must be conducted elsewhere is many orders of magnitude greater than what is absorbed by the small device.

A varistor remains non-conductive as a shunt mode device during normal operation when voltage remains well below its "clamping voltage". If a transient pulse (often measured in joules) is too high, the device may melt, burn, vaporize, or otherwise be damaged or destroyed. This (catastrophic) failure occurs when "Absolute Maximum Ratings" in manufacturer's datasheet are significantly exceeded. Varistor degradation is defined by manufacturer's life expectancy charts using curves that relate current, time, and number of transient pulses. A varistor fully degrades typically when its "clamping voltage" has changed by 10%. A fully degraded varistor remains functional (no catastrophic failure) and is not visibly damaged.

Ballpark number for varistor life expectancy is its energy rating. As MOV joules increase, the number of transient pulses increases and the "clamping voltage" during each transient decreases. The purpose of this shunt mode device is to divert a transient so that pulse energy will be dissipated elsewhere. Some energy is also absorbed by the varistor because a varistor is not a perfect conductor. Less energy is absorbed by a varistor, the varistor is more conductive, and its life expectancy increases exponentially as varistor energy rating is increased. Catastrophic failure can be avoided by significantly increasing varistor energy ratings either by using a varistor of higher joules or by connecting more of these shunt mode devices in parallel.

Important parameters are the varistor's energy rating in joules, operating voltage, response time, maximum current, and breakdown (clamping) voltage. Energy rating is often defined using standardized transients such as 8/20 microseconds or 10/1000 microseconds, where 8 microseconds is the transient's front time and 20 microseconds is the time to half value.

To protect communications lines (such as telephone lines) transient suppression devices such as 3 mil carbon blocks (IEEE C62.32), ultra-low capacitance varistors or avalanche diodes are used. For higher frequencies such as radio communication equipment, a gas discharge tube (GDT) may be utilized.

A typical surge protectorpower strip is built using MOVs. A cheapest kind may use just one varistor, from hot (live, active) to neutral. A better protector would contain at least three varistors; one across each of the three pairs of conductors (hot-neutral, hot-ground, neutral-ground). A power strip protector in the United States should have a UL1449 3rd edition approval so that catastrophic MOV failure would not create a fire hazard.

## Hazards

While a MOV is designed to conduct significant power for very short durations (â‰ˆ 8/20 microseconds), such as caused by lightning strikes, it typically does not have the capacity to conduct sustained energy. Under normal utility voltage conditions, this is not a problem. However, certain types of faults on the utility power grid can result in sustained over-voltage conditions. Examples include a loss of a neutral conductor or shorted lines on the high voltage system. Application of sustained over-voltage to a MOV can cause high dissipation, potentially resulting in the MOV device catching fire. The National Fire Protection Association (NFPA) has documented many cases of catastrophic fires that have been caused by MOV devices in surge suppressors, and has issued bulletins on the issue.

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Actinium (revised)

Noble Gases NOBLE GASES

Question:I am 33, 5 foot 6, very active (swim, walk a lot, have started yoga and belly dancing, and do sit-ups, 25 a day, and push ups about 15 a day). I have a lot of muscle in my arms and legs. I have a little bit of a baby condo left from having my third child, but other then that my stomach is relatively flat. My BP is usually around 110/60. But here is the thing, I way 223 lbs. When I have people geuss my weight people usually say about 150, I know some of that is trying to be polite but some seem genuinely suprised when I say what I weigh. According to the BMI I am morbidly obese, but I don't feel it. I told my mother and a co-worker that I want to lose 70 lbs they said that I would look like a skeleton. My doctor says weightloss would be good, but he also says that I am in perfect health, so what do you folks think???? Go by weight or go by how you look, act and feel?????

Answers:BMI is only an estimate of your weight distribution. It does not really take into account or differentiate muscle/fat ratios or bone structure. When I was in the army the soldiers who worked out with heavy weights and therefore had higher than usual muscle mass (which is denser than fat) always exceeded the charts and had to have more specialized measurements done. The most accurate way to determine your muscle/fat ratio is to have a physician weigh you on dry land and also submersed in a pool. Since fat is less dense than muscle the difference in weight between the dry weigh-in and the submerged weigh-in gives a more accurate measure of fat percentage in your body weight. If you are truly concerned then you should consult with a physician who will use a more precise evaluation than just looking at a chart. Diet and activity levels are as important in determining over all health as is body fat levels.

Question:I have just purchased the MaxView Analyser Scale, Model: 9124SS3R. It gives me the following readings regarding my body composition: Total weight: 136lbs. Body fat percentage: 20.9% Muscle mass: 39.7% body water: 50.9% For some reason my body fat and muscle mass don't add up to my total weight. I can't seem to figure out why not, or even if they are supposed to. At the moment there is a significant amount of my body weight left unaccounted for. Any help would be appreciated. Re: bone organs etc. Yes this is what I was thinking, but how much total weight should be attributed to these? Also re: the calculation of body fat + body water + muscle mass = total weight, based on the stats given these add up to more than my total weight. Does any one know why a large amount of total weight would be unaccounted for?

Answers:You're made up of more than muscle and fat, otherwise it would be possible to get your weight near 0 lbs.

Question:I have this weight watchers scale(it's super light and slim if anyone knows the specific one I am talking about) this scale that reads body fat weight, percentage, bmi, body water and bone mass. I went on it today. does this sound healthy? most of these are in KG unit. ((the decimal points might be in the wrong place because it's really hard to read them when your on the scale)) Height: 5ft 6inches 55.5 KG ((122 pounds)) 5.0 body fat weight ((kg i'm guessing)) 11.0 body fat percentage 20.0 BMI 19.7 BODY WATER( percentage) 58.4 bone mass ((again the decimals may be in the wrong place. cuz they are really tiny and small to read when your standing up on scale))((Makes more sense if this one was PERCENTAGE TOO)) and the last number was 6.6 but was not sure what that was for or whatever.

Answers:You sound healthy to me. 5'6" and 122 lbs is a good weight. A 20 BMI is also good.

Question:I am just starting a new regimen of watching calorie intake, excercising 3 times a week (treadmill at 3 mph 20 min, hand weights, resistance chords) What else can I do? Should I be concerned with the % Body water? Research on the web says I should have more like 50-60% body water? Thanks for the advice! Here are my stats: 33yrs old current weight 305.8lbs 58.6% Body Fat Bone Mass = 4.6 lbs Body Water = 31.6% Muscle Mass = 34.8% BMI = 41

Answers:give yourself time to adjust. you wont lose weight right away. sometimes those devices that read body water percentage and stuff like that arent very reliable. i wouldnt read to much into it.