Ha. A glass of low carb wine...You should have asked before I had some wine, but yes I think so.
Well....funnily enough my industrial experiences have been with tubing thousands of feet long pumping a fluid that contains varying concentrations of salt (but not sugar) through diameters of just a few inches. So if the salt concentration is raised then the pressure is raised or if there is a constriction from debris then again the pressure is raised. The only thing is that the tubing is made of relatively inert and inelastic iron. So that is where my original analogy falls down, I think.Hi @ all, From my simplistic view, modified by reading but not as professional advice or opinion:
Blood pressure is pulsatile, regulated by a pump, the heart, and the (usually elastic) calibre or cross-sectional size and elasticity of the arteries.
Factors that can affect the pump are things like adrenaline (up strength of contraction and speed), other substances slow pulse and strength e.g. .beta blockers
Factors affecting the size of the arteries, often referred to as the resistance of the peripheral (away from the heart) blood vessels (or peripheral resistance) where resistance refers to the fact that the narrower the blood vessel, within reason, pumped with blood the higher the pressure in it is, the larger the vessel expands the lower the resistance and therefore pressure.. ( think of water being pumped through a garden hose, if you partially obstruct the hose the jet of water squirts further because the pressure has increased in the hose.)
Large intake of salt makes some (not necessarily all) people's peripheral arteries close up a bit - up goes the blood pressure.
Our kidneys, being filters, need a head of pressure to do their filtering job and so if the blood pressure falls off a bit the kidneys release a substance that causes an increase in the peripheral resistance to help compensate.
Some BP medication relaxes arteries and BP goes down.
Of course there are other things: if I am bleeding strongly enough ( like one thousand finger pricks at once)! then the volume of blood to be pumped around might fall and the pressure drops with it, like the hose has a leak in it.
If I stand up suddenly, my blood pressure might fall a bit because gravity is making it more difficult for the blood in my feet and legs to get back to my heart. My body adapts by adjusting my blood pressure up (stronger heart beat, increased pulse rate, some increase in the peripheral resistance) and the muscles in my legs might help by pressing on the veins to stop blood pooling in my feet and veins have valves that stop blood slipping back down towards my feet.
If I faint, then my heart is more or less level with my feet, gravity has asserted itself and the fainting has helped solve the problem, but created the lump on my noggin !!
There are hormones, besides adrenaline and nerves involved in the circuitry controlling the heart and arteries as well. If the nerves to my blood vessels, controlling calibre are injured, I may faint after standing up, because the peripheral resistance does not increase. The signal is not able to get through.
As I age my arteries may become less elastic ( like an old sock), there is not the same 'give' and "return' in these arteries. The force of the blood pumped by heart is not softened as it would be with the elasticity gone. The BP might fluctuate more, like water being pumped through a pipe.
Now if the blood is thicker than usual the heart might have to work harder, but the arteries might relax a bit to allow the blood to flow more easily, plus the arteries, if elastic, might accomodate the thicker blood's impact on them. There might be some blocking up of capillaries, those smallest of blood vessels servicing cells , before joining up to form veins. Or the weins where flow of the blood is slower might block or develop blood clots.
But the blood has to be very thickened such as when unfortunate people suffer from a excess of cells in their blood stream to have capillaries, veins etc blocking up.
I have not found the answer for what happens with thickened blood pumped through age-related, inelastic arteries, though !!
Now, this chappie in Scotland was saying the subject of BP is very complex.
You might think of Blood Pressure as a pump, with hoses with thinner and wide sections, sprinkler system with retrieval of water. back to the pump.
But then to make it run on automatic, in all conditions is a tad complicated !!!
Reference: Wikipedia - Blood Pressure
Hi @Listlad, I thought your question was a very good one. And I had in my own mind partly tricked myself into thinking that the garden hose has some stretchiness in it. It would be an interesting experiment to trial various hose and pipe materials and viscosity concentrations (if that is the correct term) to see how things work.Well....funnily enough my industrial experiences have been with tubing thousands of feet long pumping a fluid that contains varying concentrations of salt (but not sugar) through diameters of just a few inches. So if the salt concentration is raised then the pressure is raised or if there is a constriction from debris then again the pressure is raised. The only thing is that the tubing is made of relatively inert and inelastic iron. So that is where my original analogy falls down, I think.
(The garden hose pipe analogy is one that we often use).
Okay. That’s another area then, the mode of flow. And that would no doubt relate to the viscosity of the blood, flow rate of the blood and the friction on the walls of the arteries and veins. We tend to talk about laminar and turbulent flow but am not sure how that translates into blood flow in the body.Hi @Listlad, I thought your question was a very good one. And I had in my own mind partly tricked myself into thinking that the garden hose has some stretchiness in it. It would be an interesting experiment to trial various hose and pipe materials and viscosity concentrations (if that is the correct term) to see how things work.
Another variable may be the degree of friction and turbulence along the walls of a blood vessel versus plastic tubing.
Also I have read, but cannot find the reference, that the pulsatile movement of blood in the arteries is in a toroidal fashion. I imagine a series of smoke rings progressing down the blood vessel but the clash between smoking and blood vessel health threatens to topple that analogy every time !!
If I faint, then my heart is more or less level with my feet, gravity has asserted itself and the fainting has helped solve the problem, but created the lump on my noggin !!
I am sure they are all connected yes.Thank you. And I can imagine cavitation at high speeds, turbulence at bifurcations and so on.
I am more familiar with laminar flow, vortex formation and turbulence to do with kites but I guess similar concepts apply.
Of course I know very little about wind tunnels or confining enclosures and boundaries like a tube.
If the pump pulse sends a laminar flow of blood down the centre of the blood vessel and a rolling toroidal flow (? rolling backwards maybe) along the walls how would that affect the layers at the inner toroid and outer laminar flow boundaries.?
And if the blood vessel wall expands as the toroidal movement hits and rolls down the vessel, does that flexing of the wall allow less force to be transferred in towards those boundary layers ?
And then the wall rebounds inward and maybe pushes the blood flow onward as well??
And there are pressure receptors, nerves to arterial walls and who knows what else playing a part in the process?
Thank you. And I can imagine cavitation at high speeds, turbulence at bifurcations and so on.
I am more familiar with laminar flow, vortex formation and turbulence to do with kites but I guess similar concepts apply.
Of course I know very little about wind tunnels or confining enclosures and boundaries like a tube.
If the pump pulse sends a laminar flow of blood down the centre of the blood vessel and a rolling toroidal flow (? rolling backwards maybe) along the walls how would that affect the layers at the inner toroid and outer laminar flow boundaries.?
And if the blood vessel wall expands as the toroidal movement hits and rolls down the vessel, does that flexing of the wall allow less force to be transferred in towards those boundary layers ?
And then the wall rebounds inward and maybe pushes the blood flow onward as well??
And there are pressure receptors, nerves to arterial walls and who knows what else playing a part in the process?
Thank you @Listlad, that is an awesome photo. I cannot match the vortex display but these bols as they are called certainly whirl around.I am sure they are all connected yes.. I hadn’t thought of the kite side of things.
Here is a nice pic sourced on the net:
Ref your pic. We didn’t actually see anything like that in Lytham St Anne’s last year but I have seen similar in photos.Thank you @Listlad, that is an awesome photo. I cannot match the vortex display but these bols as they are called certainly whirl around.
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They are controlled by many kite lines attached to the perimeter, and drawn into a spinner assembly about 3 to 4 metres in front of the bol. Slots in the material are angled so that the breeze causes the structure to spin. The bols were actually spinning in opposite directions. Now if only they could be geared somehow to produce electricity .......Ref your pic. We didn’t actually see anything like that in Lytham St Anne’s last year but I have seen similar in photos.
When I first saw those shots I thought it was Lytham St Anne’s. Yes they both have a pier / jetty.Thank you @Listlad. That looks like a marvellous viewing platform/jetty and a great skyline/backdrop for all the wonderful kites.
Where things are added to kite lines along their length below the main kite we called those things 'line laundry'.
Never had anything to actually dry on the line but is does help fill the 'gaps' in with colour and movement.
3 aerial shots from Adelaide, taken by a camera suspended from a kite. the 4th a panorama (Mark is a club member)
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Well I don’t know if it’s normalising my blood sugar or losing over six stone, both from low carbing, but my BP before diagnosis, on 2 meds’ was around 145/85. Now it’s around 125/75 on just one med![]()
It’s that time of the year again here. 10th and 11th August.Thank you @Listlad. That looks like a marvellous viewing platform/jetty and a great skyline/backdrop for all the wonderful kites.
Where things are added to kite lines along their length below the main kite we called those things 'line laundry'.
Never had anything to actually dry on the line but is does help fill the 'gaps' in with colour and movement.
3 aerial shots from Adelaide, taken by a camera suspended from a kite. the 4th a panorama (Mark is a club member)
View attachment 30977 ..............View attachment 30978 .......................View attachment 30979 .......................View attachment 30980