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      Welcome!   03/05/2016

      Welcome, everyone, to the new 910CMX Community Forums. I'm still working on getting them running, so things may change.  If you're a 910 Comic creator and need your forum recreated, let me know and I'll get on it right away.  I'll do my best to make this new place as fun as the last one!
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NP Monday January 20, 2017

72 posts in this topic

4 hours ago, Vorlonagent said:

Wouldn't boiling or otherwise evaporating the water be the energy challenge with desalinization as well?

To kill the bacteria, you don't actually need to boil the water. However, that's the easy way to make sure that it's hot *enough* to do the job. Does not require temperature-sensing equipment. Also, killing the bacteria can be done in small-scale operations by people with almost no training. Of course, you have to actually have some (otherwise-drinkable) water first...

The old-fashioned way of desalination involves making the water evaporate. That takes a lot more energy than merely heating it to boiling for a moment. And then you gotta get the water to re-condense where you want it to. This takes special equipment and a degree of technical expertise to maintain and operate the equipment. The new-fangled way is a reverse osmosis process, which takes considerably less energy (still quite a bit though) but is even more demanding in terms of special equipment and technical expertise.

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When the Romans were "protecting" Alexandria during the civil war between Cleopatra and her brother/husband Ptolemy the Last, the legions built a solar powered water distillation/desalinization facility from their shields.

To build similar facilities with modern materials requires a lot of land near the coast, or a lot of piping and pumping seawater a long way inland.  The cost of large tracts of undeveloped/unprotected land near both the coast and residential or industrial areas is considerable.  The risk of seawater leaking from pipes and contaminating inland aquifers is significant.

Also, desalinated water tends to lack minerals and trace chemicals that are essential for health.  Iodine deficiency is a frequent health risk in populations that depend on desalinization for most of their water.  Adding chemicals to public drinking water supplies is still controversial in some circles.

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7 hours ago, Don Edwards said:

To kill the bacteria, you don't actually need to boil the water. However, that's the easy way to make sure that it's hot *enough* to do the job. Does not require temperature-sensing equipment. Also, killing the bacteria can be done in small-scale operations by people with almost no training. Of course, you have to actually have some (otherwise-drinkable) water first...

If it's just a bacterial soup that needs to be sterilized then the sun can do a surprisingly good job, and that without heating it anywhere near the boiling point. Just leaving a water filled PET bottle in the sun for six hours can be enough to kill of enough bacteria that it's safe to drink. The exact time required depends on the amount of sunlight available, the bottle quality, how clear the water is, and how much bacteria there was in the water to begin with. This is called the SODIS method.

Read more about it here on Wikipedia, or on the site www.sodis.ch

Note that one of the shortcomings of this method is that it doesn't remove anything from the water, so any poisonous contaminant or particulate matter will remain even though the bacteria is dead.

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15 hours ago, Pharaoh RutinTutin said:

When the Romans were "protecting" Alexandria during the civil war between Cleopatra and her brother/husband Ptolemy the Last, the legions built a solar powered water distillation/desalinization facility from their shields.

Were they using the same kind of shields Archimedes used to burn Roman ships? Because I suspect the secret of those highly reflective shields was lost just like Greek fire.

15 hours ago, Pharaoh RutinTutin said:

Also, desalinated water tends to lack minerals and trace chemicals that are essential for health.  Iodine deficiency is a frequent health risk in populations that depend on desalinization for most of their water.  Adding chemicals to public drinking water supplies is still controversial in some circles.

It's about trust. Most people don't trust politicians to add anything to water because they have experience with how competent and incorruptible they are(n't).

8 hours ago, Cpt. Obvious said:

Just leaving a water filled PET bottle in the sun for six hours can be enough to kill of enough bacteria that it's safe to drink. The exact time required depends on the amount of sunlight available, the bottle quality, how clear the water is, and how much bacteria there was in the water to begin with. This is called the SODIS method.

Read more about it here on Wikipedia, or on the site www.sodis.ch

I'm pretty sure the six hour figure only applies near the equator. Of course, the SODIS method is mostly developed FOR the countries around equator, but that doesn't change the fact that it will NOT work elsewhere.

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A quick search says that the six hour standard time for SODIS is in "mid-latitude" areas, so Florida should be okay.

So when I visit the Conch Republic, I just have to make sure I leave any refilled bottles of water sitting in the sun, preferably on top of a reflective corrugated roof, for a full day before drinking it.  Good to know.  

(ETA: A little further reading, they say the ideal range for SODIS is between 15 and 35° (north or south).  Key West is at about 25° N, so it's smack in the middle of ideal.)

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Something I thought was interesting was the claim that in case there is constant rain and full cloud cover it will still sterilize the water, but it can take up two weeks to do it. But if it rains constantly for two weeks then you should be able to collect quite a lot rainwater that most likely is way cleaner than the water you are trying to sterilize.

SODIS is not something that will solve the worlds water problems all on it's own, but it is extremely cheap and simple.
 

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37 minutes ago, Cpt. Obvious said:

Something I thought was interesting was the claim that in case there is constant rain and full cloud cover it will still sterilize the water, but it can take up two weeks to do it. But if it rains constantly for two weeks then you should be able to collect quite a lot rainwater that most likely is way cleaner than the water you are trying to sterilize.

Yup, and if you read their recommendations, that's exactly what they advise when it's too rainy for SODIS.  Collect the rainwater.  Just have to make sure the container(s) it's collected into aren't contaminated.

37 minutes ago, Cpt. Obvious said:

SODIS is not something that will solve the world's water problems all on its own, but it is extremely cheap and simple.

It won't kill everything in every water supply, but what they've proven is that people who practice SODIS get less diarrhea than their neighbors who don't when both use the same water supply.  In third world countries, diarrhea can be lethal, as well as keeping kids out of school and parents out of work.  I wouldn't turn my back on a new cancer treatment just because it only reduced cancer deaths instead of eliminating them completely, the same applies here.  :-)

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22 hours ago, CritterKeeper said:

In third world countries, diarrhea can be lethal

I think this has less to do with them being third world countries and more with "If only source of water you have is the one which caused you diarrhea, you will die".

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5 hours ago, ijuin said:

That, and having no access to antibiotics when you do get an infection . . .

Take heart. This will soon become the norm in first world countries, too. As more and more superresistant strains develop while our governments fritter away what antibiotics still do work through such strokes of genius as cutting funding for hospital hygiene, we are a mere decade or two away from living in the happy times of the early twentieth century where the surest way of getting rid of an infection was through amputation.

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12 hours ago, hkmaly said:

I think this has less to do with them being third world countries and more with "If only source of water you have is the one which caused you diarrhea, you will die".

That's part of it, but only one part.  In a first world country, IV fluids can correct the dehydration diarrhea causes before it becomes too severe, and anti-diarrheal medications are readily available (Pepto-Bismol, Immodium, etc) to reduce the fluid loss in the first place.  Labs can identify the bacteria or parasite responsible, and medications targeted to the cause are easily and cheaply obtained.  Heck, we have enough resources to do all of that for our pets, let alone human beings.  I do much of that every week!

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3 hours ago, The Old Hack said:

Take heart. This will soon become the norm in first world countries, too. As more and more superresistant strains develop while our governments fritter away what antibiotics still do work through such strokes of genius as cutting funding for hospital hygiene, we are a mere decade or two away from living in the happy times of the early twentieth century where the surest way of getting rid of an infection was through amputation.

This and the way doctors are worn down by all the people who feel they deserve to have antibiotics every time they sneeze. Eventually it all gets to much and they will write out that prescription just to get rid of the bellyaching parents with their coughing kids, even though they all know that antibiotics does absolutely nothing for the common cold.

And don't even start talking about large scale chicken, pork and beef production. So much antibiotics used preventively and so much money spent to stop people from researching this.

Greed and stupidity is going to ruin our current antibiotics for everyone. And unfortunately it seems like it will be hard to find good replacements. It used to be that antibiotics resistance wasn't seen as a problem. After all they just had to make a new one, right? But we're quickly running out of new and easily researched antibiotics, and the cost of development is rising.
 

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Yeah, it seems like a lot of people expect modern medicine to keep them infection-free and can't stand to be sick for a few days (maybe because medical care is such a big money eater that we expect more from it than we get). I'm sorry, but anything that you are nearly 100% certain to recover from without permanent harm is less important than preventing deaths, and such people should go in the "will recover without intensive treatment" category of triage.

As for antibiotics in general, we should probably in the long term move to using the more directly targeted bacteriophage viruses as an infection fighter. Each strain of bacteriophage is the natural predator of specific strains of bacteria, which also means that there will be much less collateral damage (e.g. beneficial gut bacteria being killed off by oral antibiotics, leaving the gut open to colonization by something less benign). It is analogous to deploying mosquito-eating creatures such as dragonflies instead of spraying with insecticide.

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10 hours ago, The Old Hack said:
15 hours ago, ijuin said:

That, and having no access to antibiotics when you do get an infection . . .

Take heart. This will soon become the norm in first world countries, too. As more and more superresistant strains develop while our governments fritter away what antibiotics still do work through such strokes of genius as cutting funding for hospital hygiene, we are a mere decade or two away from living in the happy times of the early twentieth century where the surest way of getting rid of an infection was through amputation.

If we manage to not defund research for little longer, we may find some new ones, for example Peruvian pepper.

9 hours ago, CritterKeeper said:

That's part of it, but only one part.  In a first world country, IV fluids can correct the dehydration diarrhea causes

... because the IV fluids are not contaminated water. Putting contaminated water in through IV will be even worse idea than drinking it.

6 hours ago, Cpt. Obvious said:

This and the way doctors are worn down by all the people who feel they deserve to have antibiotics every time they sneeze. Eventually it all gets to much and they will write out that prescription just to get rid of the bellyaching parents with their coughing kids, even though they all know that antibiotics does absolutely nothing for the common cold.

Hey, what if they just describe the antibiotics which most bacteria are already resistant? They can sincerely said that it will work just as good as the new antibiotics on the viral infections and it will be cheaper.

(Of course, SUGAR would work just as good as well and will be even cheaper, but people are getting too good discovering placebos.)

35 minutes ago, ijuin said:

As for antibiotics in general, we should probably in the long term move to using the more directly targeted bacteriophage viruses as an infection fighter. Each strain of bacteriophage is the natural predator of specific strains of bacteria, which also means that there will be much less collateral damage (e.g. beneficial gut bacteria being killed off by oral antibiotics, leaving the gut open to colonization by something less benign). It is analogous to deploying mosquito-eating creatures such as dragonflies instead of spraying with insecticide.

Yes, and if there is no bacteriophage for that specific infection we just make it - oh wait, some people are against genetic research. Let's hope they get the resistant bacteria first.

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9 hours ago, Cpt. Obvious said:

And don't even start talking about large scale chicken, pork and beef production. So much antibiotics used preventively and so much money spent to stop people from researching this.

Not even really preventively.  They've been used as "growth promotants," meaning they'd give animals a low dose of antibiotics every day, just because someone figured out they'd grow a little faster and be ready for market a little sooner.  Talk about a perfect recipe for creating resistance!  It's one of the stupidest things I know of, and one the profession and government are only now cracking down on.

3 hours ago, hkmaly said:

If we manage to not defund research for little longer, we may find some new ones, for example Peruvian pepper.

"But surely the drug companies can pay for all that expensive research!  Why should government get involved?"  And people wonder why drugs are so expensive and research is so meager and erratic.

Quote

... because the IV fluids are not contaminated water. Putting contaminated water in through IV will be even worse idea than drinking it.

IV fluids are more than just water.  Blood and other body fluids are a certain concentration, and we have to add enough electrolytes (and/or sugars) to make the fluids the same concentration, or bad thigns happen.  And yes, they have to be sterilized, which means most third world countries can't afford very much of them. 

Quote

Hey, what if they just [pr]escribe the antibiotics which most bacteria are already resistant? They can sincerely said that it will work just as good as the new antibiotics on the viral infections and it will be cheaper.

Unfortunately, there isn't a waiting line, where all bacteria become resistant to one antibiotic and then the next.  Even simple penicillin, the antibiotic in use the longest, still has plenty of cases where it's perfectly usable.  Bacteria can both gain and lose resistances over time. 

 

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15 hours ago, CritterKeeper said:

Not even really preventively.  They've been used as "growth promotants," meaning they'd give animals a low dose of antibiotics every day, just because someone figured out they'd grow a little faster and be ready for market a little sooner.  Talk about a perfect recipe for creating resistance!  It's one of the stupidest things I know of, and one the profession and government are only now cracking down on.

To say nothing of "anti-bacterial" soaps...

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2 hours ago, Vorlonagent said:

To say nothing of "anti-bacterial" soaps...

The problem with them is that they kill bad bacteria and normal flora, which allows later bad bacteria to more easily fill the niche left vacant by the normal bacterial flora.

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Yes--your normal, healthy skin bacteria generally don't do anything more harmful to you than giving you the occasional pimple, and they drive away the worse bacteria.

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20 hours ago, CritterKeeper said:
23 hours ago, hkmaly said:

If we manage to not defund research for little longer, we may find some new ones, for example Peruvian pepper.

"But surely the drug companies can pay for all that expensive research!  Why should government get involved?"  And people wonder why drugs are so expensive and research is so meager and erratic.

Just because the drug companies CAN pay it doesn't mean they WILL. And, yes, whoever pays for the research is setting up priorities. If the drug companies are paying it, the priorities would be based on how they can get more money.

20 hours ago, CritterKeeper said:
Quote

... because the IV fluids are not contaminated water. Putting contaminated water in through IV will be even worse idea than drinking it.

IV fluids are more than just water.  Blood and other body fluids are a certain concentration, and we have to add enough electrolytes (and/or sugars) to make the fluids the same concentration, or bad thigns happen.  And yes, they have to be sterilized, which means most third world countries can't afford very much of them. 

I know and I actually wanted to say "are not made from contaminated water" ... although, maybe the contaminated water would have correct osmotic pressure :)

20 hours ago, CritterKeeper said:
Quote

Hey, what if they just [pr]escribe the antibiotics which most bacteria are already resistant? They can sincerely said that it will work just as good as the new antibiotics on the viral infections and it will be cheaper.

Unfortunately, there isn't a waiting line, where all bacteria become resistant to one antibiotic and then the next.  Even simple penicillin, the antibiotic in use the longest, still has plenty of cases where it's perfectly usable.  Bacteria can both gain and lose resistances over time. 

... and what's unfortunate on it?

Bacterias are getting most resistant to the antibiotics most often overused (assuming every antibiotics is similarly easy to develop resistance on, which is not true, and not counting effects of location). Therefore, it makes sense to only use new antibiotics which bacteria are not resistant to yet only in important cases (like when curing infections caused by those resistant bacterias) and using the most overused antibiotics (which may not be penicillin, maybe because while oldest, penicillin is hard to use - needs to be taken often - and maybe it's also one of those harder-to-get-resistant ones) in "preventive" cases like viral infections or as "growth promotants".

2 hours ago, CritterKeeper said:
5 hours ago, Vorlonagent said:

To say nothing of "anti-bacterial" soaps...

The problem with them is that they kill bad bacteria and normal flora, which allows later bad bacteria to more easily fill the niche left vacant by the normal bacterial flora.

If you can prove that, contact FDA. Seems that their latest concern is that there’s no data demonstrating that these drugs provide additional protection from diseases and infections. In short, major problem with those anti-bacterial soaps is that they were called anti-bacterial by marketing, not by scientists.

...

Hmmm, what exactly is Susan using?

 

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1 hour ago, hkmaly said:

If you can prove that, contact FDA. Seems that their latest concern is that there’s no data demonstrating that these drugs provide additional protection from diseases and infections. In short, major problem with those anti-bacterial soaps is that they were called anti-bacterial by marketing, not by scientists.

I'm willing to bet that the "anti-bacterial" soaps were not specifically tested against disease-causing agents and were instead tested merely against the typical mix of bacteria that people find on their hands (coming from touching garbage, feces, or other common filthy things).

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Well, the concern about killing good bacteria is what I'd read in the past.  We get a heck of a lot of FDA notices and emails at work, so I guess they changed focus at some point and I missed it.  That, and worries about whether triclosan affects hormones.

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1 hour ago, hkmaly said:

Hmmm, what exactly is Susan using?

Hand sanitizer isn't so much anti-bacterial, it's an alcohol based product which by nature kills off bacteria. Usually when something is labelled as anti-bacterial, it means it prevents the growth of bacteria.

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