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9

Hodgins AM, Mittal GS, Griffiths MW. 2002. Pasteurization of Fresh Orange Juice Using Low-Energy Pulsed Electrical Field. J Food Sci 67(6):2294-2299 This is a study of non-thermal food preservation, but it cites two studies that measured ascorbate loss from pasteurisation. I can't cite the studies directly because I can't find them online. According to ...


8

Afaik the tongue is not more heat tolerant than other parts of the body, so the minimum temperature to cause burn is about drinking a beverage having 45°C temperature for a long time (more than 5 minutes). The pain threshold of tongue is around 47°C, so you will feel when it really burns. According to studies the hedonic value of coffee has a maximum by 60°...


5

This depends on a lot of factors, including how you take your first sip. If you sip with air, you are altering the temperature of the liquid as you sip, as well as decreasing the volume of hot liquid in your mouth, so that the increased surface area of your exposed tongue can quickly alter the temperature of a borderline scalding liquid into a non-scalding ...


5

Pores don't change size; that is, the diameter of pore does not increase or decrease in hot or cold environments. Your skin, where pores are located, is not muscle but an organ so the pores don't contract or expand. Pores can become clogged with dirt, oil, and debris (make up). When pores are clogged, you are more inclined to notice which would cause the ...


4

There has been a long debate whether dinosaurs were ectotherms or endotherms but most of the recent studies (hypotheses)1 show that they were endotherms. In one of the most promising recent studies (in 2011), a technique called clumped-isotope thermometry2 (which is based on a reaction involving the bond between carbon and oxygen; and used in paleoclimate ...


4

Take a look at the Temperature paragraph from this reference: Ecophysiology Plants can avoid overheating by minimising the amount of sunlight absorbed and by enhancing the cooling effects of wind and transpiration. They seem to have several ways to counter the heat as we do with transpiration, wind etc. This article is more complicated but as really ...


3

Here is a good article on the topic. https://www.nlm.nih.gov/medlineplus/ency/article/003227.htm But it's most likely due to the fact that a sun burn is an actual burn on the skin that can cause inflammation, inflammation can in turn cause fever. Also having a really bad sunburn can open you up more to the possibilities of skin infections. If this happens ...


3

Is heat released during work due to ATP breakdown or a increased blood flow? Short answer: neither. Most of the heat generated is due to poor efficiency of metabolism. It is a common misconception that ATP is the same thing as energy when it comes to metabolism. ATP is certainly a very important energy carrier, but human metabolism is far from efficient at ...


3

Is heating of a body the result of increased blood flow or extra energy from ATP? It is mainly because of the breakdown of ATP (Adenosine Triphosphate, a type of nucleic acid with an Adenosine base, a Ribose sugar, and 3 Phosphate groups), alternatively and more formally known as ATP Hydrolysis. During hydrolysis by water, ATP splits into Adenosine ...


3

Your extremities lose heat at a faster rate than the rest of your body because they have higher surface area per unit volume. Heat exchange happens at surfaces, so if you have more surface, you transfer heat more quickly. Imagine you have a sphere of water with 1L volume, and a long cylinder of water, also 1L, lets say 1cm wide, the sphere will hold heat ...


2

Most likely, you can't assume that $h/k$ might be constant. Reason is that those parameters are characteristics of two very separate systems. Thermal conductivity shows how fast heat can be propagated through material. That is, it answers question: if block of metal has $T_0$ temperature on its surface A, and you apply temperature $T_1$ (higher) to opposite ...


2

There are a number of ways, which are briefly summarized here. I also recommend reading this nice Scitable article on thermoregulation. It is not too technical. Felines do pant when they get hot. Horses do sweat. Jackrabbits can enlarge the blood vessels in their large ears to eliminate excess heat. Bird use a process called gular flapping, which is similar ...


2

Firstly, movement by shuddering or shivering, in simplicity, effects the conversion of potential energy into kinetic energy. This is achieved by expending ATP in muscular tissue, causing rapid bursts of contraction. Brown adipose tissue, although located within most mammals ranging from infants to elderly, is predominantly found in infants differing from ...


2

The calorie is a unit of energy. Our body uses the energy found in food to create ATP (a molecule that is handy to deal with energy) with the help of oxygen (that we breath in). ATP can then be used for plenty of tasks such as importing ions through a cellular membrane or more ultimately walking, talking, warming up your body, etc... Saying that some food ...


1

First, you have to convert your numbers to the same units for any comparison to make sense. Consider that the average human body has a surface area of about 1.8m$^2$ and a volume of about 66L = 0.066m$^3$. Then your numbers are equivalent to 2230W metabolic heat and 1050W exercise heat for an average person. The value 2230W for basal metabolic rate (from ...


1

Read this it was very helpful to me as a Reiki Practitioner who wants to know how the heat generated by my hands on therapy with my patients for Hospice brings such relaxation to them. http://healthyliving.azcentral.com/effects-temperature-muscular-contraction-11504.html


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