Bioengineers+and+Incubators

=   = = Bioengineers and Incubators =

Mwaka Sipula and Kim Sinnige
=__Determining The Normal Temperature in Humans__= = This will also take you to the paper--> = The normal temperature in humans is roughly 37 degrees Celsius, but varies slightly. Temperature change is not only an effect of ill health, but can also be a cause. A temperature of 42 degrees Celsius can cause death, and is a condition called hyperthermia. If our temperature falls too low, this can also cause death, this is hypothermia. It is important that our bodies maintain an average body temperature of 37 degrees Celsius because it is necessary for the enzymes in our bodies. Enzymes are special proteins that assist the cells inside our bodies to function, and most are wiped out at a temperature of 40 degrees Celsius. The brain is one of the first organs to be affected. When our body temperature falls too low, important chemical reactions in our bodies slow down, and our brains can also be affected.

Hyperthermia leaves premature babies vulnerable and susceptible to serious illness and death. It is very important to assist premature babies to maintain a constant body temperature because they have much difficulty in doing this, and can quickly become cold. There is many different ways to measure body temperature in humans, these include:


 * Mercury-in-glass thermometers
 * Alcohol-in-glass thermometers
 * Medical thermometers
 * Disposable “dot” thermometers
 * Bead thermistors
 * Infrared sensors

With premature babies it is easiest to use the infrared sensors, because they do not want the babies to be disturbed, and they are usually very accurate. Here is some information on the different types of thermometer. >

=__The need for a mechanical device to control temperature__= = This will also take you to the paper-> =

Premature babies are unable to maintain their body temperature, or have difficulty in doing so. It is therefore necessary for an incubator to be used to create a stable environment of the right temperature to prevent the babies from getting cold and suffering from hypothermia. Premature babies are unable to warm themselves by shivering, and they have less brown fat. Brown fat is found in the neck and abdomen. It is an energy source used to keep the body warm. Although some people may think so, premature babies are not just miniature babies. They have a higher surface area to volume ratio than bigger babies, but need to maintain the same constant body temperature. It I important for mammals to have a surface : volume ratio of good size, because the bigger the surface area the more heat is lost, and if the volume is too small to support that loss, then the temperature rapidly drops. Having not spent the necessary nine months in the womb, premature babies are not fully developed. For example the skin is not fully formed, and is only a few cells thick. It is also lacking keratin for the first 3 or 4 days. Keratin is a protein that makes the skin watertight. So the premature babies lose a lot of water through the skin. An advantage in deciding what temperatures need to be set for incubators is that premature babies do not suffer much from over-heating. Most research shows that the survival rate is better when the temperature was kept above 36 degrees Celsius.
 * __

Keeping Babies Warm __**

This will also take you to the paper->[[file:Paper 3-Keeping Babies Warm.doc]]
Keeping a premature baby warm is compulsory. If a premature baby has a low temperature it immediately degreases the chance of its survival. Piere Budin wrote a book “The Nursling” (1907) showed that if the internal temperature of premature babies (measured at the rectum) was maintained their survival rates were dramatically increased.


 * **Rectal Temperature [degrees Celsius] ** ||  ||   ||   || **Survival rate ** ||


 * 32.5 – 33.5 ||  ||   ||   || 10% ||


 * <span style="font-family: 'Century Gothic','sans-serif';">36.0 – 37.0 ||  ||   ||   || <span style="font-family: 'Century Gothic','sans-serif';">77% ||

<span style="font-family: 'Century Gothic','sans-serif';">Researchers discovered that for every baby there is a “perfect” range of environmental temperature. If kept within this range the baby will use very little oxygen and heat energy that is released during respiration keeping its body temperature natural. This temperature range is called the NEUTRAL THERMAL ENVIRONMENT. For a tiny nude baby the range is very narrow. Another researcher by the name of Glasetal (1968) found that the rate of increase in body mass of a baby was significantly faster in the neutral thermal environment. It is known that the control of the body temperature of a premature baby is critical. Mestyanetal (1964) found the neutral thermal environment for babies having masses of 1.5 - 2kg was at least 34.5 degrees Celsius and for less than 1.5kg it was 36 degrees Celsius. The aim is to keep the skin temperature at 36.5 degrees Celsius at the least.
 * __<span style="font-family: 'Century Gothic','sans-serif';">Neutral Thermal Environment __**

We also did some experiments, and here are the results: <---This will also take you to the first report.

__ Report 1-Experiment paper 1 __

__Aim:__ To determine the normal body temperature in humans. __Hypothesis:__ We predict that the average body temperature in humans will be from 35-36 degrees Celsius. __Apparatus:__ · 1 Mercury-in-glass thermometer · a sterilizer for the thermometer ·  1 pen For recording the data · 1 paper collected. __ Method: __ 1) Draw out a table on you piece of paper suitable to record the data you are going to collect. 2) Sterilize your thermometer as a test, and so that it is clean. 3) Get somebody to volunteer, and place the thermometer in their mouth. 4) After about 2 minutes remove the thermometer and turn it until you are able to see the thick silvery band. 5) Record the number that the silver band reaches 6) Repeat the previous for about 10 people or more.

__ Results: __
 * Name || Gender || Temperature (degrees Celsius) ||
 * Vibz || Female || 34.5 ||
 * Angeline || Female || 35.6 ||
 * Chrispin || Male || 36.1 ||
 * Mariska || Female || 36.6 ||
 * Alex || Male || 36.7 ||
 * Kim || Female || 35.6 ||
 * Raeesah || Female || 35.2 ||
 * Nadia || Female || 36.5 ||
 * Laly || Female || 36.6 ||
 * Rhianon || Female || 36.7 ||
 * Paola || Female || 36.8 ||
 * Thomas || Male || 36.7 ||
 * Ashling || Female || 36.7 ||
 * Sun || Male || 36.6 ||

__ Analysis: __
 * || 34.0-34.5 || 34.6-35.0 || 35.1-35.5 || 35.6-36.0 || 36.1-36.5 || 36.6-37.0 ||
 * female || 1 ||  || 1 || 2 || 1 || 5 ||
 * male ||  ||   ||   ||   || 1 || 3 ||

[[file:report 1 data graph.xls]] <-Click on this link to see a graph of the results.
__ Conclusion:  __ Our results although not completely fair show that we were incorrect in our hypothesis. The average temperature was 36.7 degrees Celsius.