DPS
-
Posts
4372 -
Joined
-
Last visited
-
Days Won
24
Content Type
Profiles
Forums
Events
Posts posted by DPS
-
-
Just because you have not heard about the journal does not make it obscure. Quite on the contrary, this journal, along with Journal of the American Water Works Association is where most of the Giardia and Cryptpsporidium research has been published and has had important impacts on public policy and the way municipal treatment plants do their business.
Actually, I have worked in a lab subject to mandatory evaluation of its accuracy and precision on blind assays. No, I did not do paristology work on human specimens (much easier than doing it in environmental samples, license or no) I worked on human drug trials for a lipid therapy treatment of Type II diabetes.
The author of the paper is actually doing a huge diservice to the community by publishing information that is just plain wrong and his own conclusions based on the fact that he has never exhibited symptoms of the disease.
-
"Where was this research published?"
Journal of Applied and Environmental Microbiology
"It is hard to imagine a more primitive system of doing a lab test than the truly obscure stuff that you mention. That, of course, is typical of someone who has no clue about real-world human laboratory testing, and is confined to a basement to have the luxury of taking, say, a month to get a result.
Those of us who are skilled in running a human clincal lab, and doing clinical testing in the real world, laugh at the characterization of such testing as anything but approaching third world technology. There are so many places for error to be introduced, it is not even funny."
Clearly you are ignorant to the methodology used to examine water. The methods that you refer to as "truly obscure stuff" are described fully in 'Standard Methods for the Examination of Water and Wasterwater' published jointly by the Water Environment Federation, the American Water Works Association, and the American Public Health Association. These methods are used by virtually every lab in the country that does water testing.
Surely you should know that the methodology used for human clinical work is not applicable to environmental work. I know this because I worked in a human clinical lab (BFD, takes very little skill).
"Do you also do film reviews of pictures you have not seen? I can't imagine an institution that would have as a graduate student, a person who doesn't read a paper fully, then publishes a criticism of that paper. Any image of scientific credibility would seem to go out the window!"
What paper? I saw no published paper. What was published was one layman's opinions on the internet. What was published on the internet would not have stood up to peer review. I did indeed read the article in its entirety and I stand by my critism. And I walk out on bad movies.
And finally, you have a huge stick up your ass.
-
I'm looking for someone to so some work on my house in Tacoma. The vinyl siding and gutters need to be pressure washed and the facia, eaves and front porch will need to be painted. The job would involve some high work as the house is two story with 9 foot ceilings and a full pitch roof. If interested please email me bighurtbob@hotmail.com. Thanks.
-
-
I imagine MattP would have some good insights for you.
-
My buddy used his Vasque sundowners with aluminum strap on crampons on the North Ridge of Forbidden to good effect.
-
Very feasible. A 5.8 leader could probably solo most of the route.
-
I went and did a bunch of stuff without the rubber, so far no damage to the tool or the owner.
You should be more careful in the future, a fellow could pick up a nasty bug that way.
I too, have small hands so grip diameter was a concern for me. I have owned a pair of Pulsars and Blackbirds and liked the grip and swing a lot. Plus I found the picks to be significantly more durable than Black Diamonds.
I got a pair of Shrikes because all of my friends use BDs I and I thought it would be nice to carry only a single replacement pick between us on alpine climbs. I also like how easy picks are to replace. The small grip fits my hand well. I had straight shafts but traded Colin for his bent shafts. Colin's residual mojo has increased my climbing ability immeasureably.
-
We did the aid sections with minimal nailing (bugaboos and lost arrows) and I have read reports of it going hammerless. The usual tools are helpful; offset Aliens, HB Offset brass nuts, cam hooks, a few hooks esp in larger sizes.
-
Of the half dozen routes I have done, they all stand out as being very enjoyable for one reason or another. Its hard to go wrong with any of the choices.
-
The City of Seattle is similar to San Francisco in that they do not filter the drinking water. They just add a bit of chlorine and send it on its way. City of Seattle gets its water from three watersheds, the Tolt, the Green and the Cedar. Two are protected, one is not. The protected watersheds were found by Ongerth have statistically significant lower concentrations of Girdia and Cryptosporidium than the unprotected watersheds.
-
Shortly after being discharged from the hospital after taking a bit of a spill, a small child pointed at me and said, 'look mommy, a pirate'. I think the bandage around my head threw him off.
-
"I remember reading about the test for giardia. It is quite primitive. It consists of putting large quantities of water through a filter and examining the filter under a microscope. It relys upon the tester being able to recognize the cysts among all the various and sundry other organisms and just plain junk in the filtrand. An inexperienced technician can miss organisms and get an undercount, and I suppose count harmless ones and produce an overcount, but I think the latter less likely"
What do you mean by primitive? Bacteria are still counted by culturing the organisms on a growth medium then counting the colonies that are formed, a process developed by Koch (a man of pure culture). The process for identifying and counting Giardia and Cryptosporidium is a multi step process that evolved in two different labs. Jerry Ongerth at the University of Washington developed a method for testing small volumes (~100 liters ) of water while Lechavalier at the University of Illinois (I think) developed a method for testing large volumes of water. Ongerth’s method was more efficient and had cyst recovery rates of up to 20%, while Lechavalier’s method produced a recovery rate of around 5%. (Recovery rates were determined by spiking a volume of water with a known quantity of Giardia cyst and then processing and comparing the number identified with the number added). The main difference between the two was Ongerth filtered water through a 293 mm Nucleopore ploycarbonate membrane (remember the old MSR waterworks?). The filter would eventually clog up limiting the volume that could be filtered. The membrane was rinsed off and the rinsate collected. Lechavalier filtered water through a wound polycarbonate depth filter. The filter then had to be chopped up in a blender, rinsed out and the rinsate collected.
The rinsate was centrifuged, concentrating the cysts, then the concentrate filtered again. The cysts and oocysts were captured on a 13mm Nucleopore polycarbonate filter. An epifluorescent stain that is conjugated to antibodies is applied. The stain is rinsed off. Since the stain is conjugated to antibodies, and the antibodies stick to antigens on the cyst surface, only the Giardia and Cryptosporidium cysts and oocysts are stained. Then a counter stain of ethidium bromide is applied. Ethidium bromide is a DNA stain which sticks to the DNA inside the cysts. Then you view the filter under a microscope with a fluorescent light source. The cysts and oocysts glow bright apple green with the bright red ‘eyes’ in the middle. Positive identification is made by viewing the organelles.
Over counts are possible by inexperienced technicians, but once you see what a cyst/oocyst looks like, its kind of hard to make a mistake. Either method grossly underestimates the number of organisms in the sample, however a correction factor can be applied based on the recovery rate of spiked positive control samples that are run in the same batch.
"Have you tested city water before? I thought it was very interesting in the research from the original post that San Francisco water had more giardia than the streams tested in the Sierras. I would have to agree that the testing methods used in the Sierras is probably not the most precise (since you can't pack in that much equipment), but if they were using the same testing methods to test San Francisco water and were consistently coming up with more giardia there I would expect that there is some truth.
Either way, the research still tells me that high mountain water is GENERALLY just as safe as city water (and safer than San Francisco water). This would be particularly true during spring run off since cysts can only survive for as long as 2 to 3 months in cold water and they cannot tolerate freezing. Let giardia sit in a lake from the onset of winter and 5-6 months later when it thaws out it's generally or completely free of giardia. But then again, all it takes is one infected/carrier gumby or animal pooping in the lake."
Keep in mind that chlorine will kill some of the cysts, particularly if there is a high enough residence time and it is difficult to differentiate an inactivated cyst from an active one. Even if the municipal water had more cysts, some of them would certainly be inactive, therefore it is erroneous to assume that mountain water is as same as municipal water. Also, don’t forget about bacteria. While I found at the most a few cysts per 100 liters, I found tens of thousands of colony forming fecal coliform units per 100 mls in many of the samples.
I have not read the entire article, but so far I have found it to be poorly researched, poorly referenced, and contained many glaring errors. I started reading this and I wondered how a pHD could publish such a piece of crap, then I read his bio. He is an engineer. Engineers make the worst biologists. Towards the end of the article he recommends drinking from fast moving water. This makes absoultely no sense. Giardia and Cryptosprodium are more dense than water and will sink unless suspended by turbulence. Better to get your water from a calm spot.
-
Interesting post. I did my graduate research on Giardia and Cryptosporidium 10 years ago. This was about the same time that the PUR water filter was introduced. AAI slapped their Guides Choice award on it. I challenged the gear manager about this and said that the guides liked it because it was easy to pump. I expained that the iodine matrix is worthless because there is no residence time. He was not impressed with my argument.
A number of years ago I interviewed with Cascade Designs to do testing on the Sweetwater filter. They had just aquired the company and wanted to prove it could remove/kill virus particles. I ended up not getting the job because they were looking for a virologist and my experience was with bacteria and protozoans.
At any rate, I ran into the fellow who interviewed me last week. (We live in the same neighborhood). He said that their microbiologist tested PUR filters along side Sweetwater and found both to be ineffective. My friend brought this to management's attention who refused to believe. He eventually left the company.
For what it is worth I use chlorine dioxide to disinfect water, a two part chemical that is mixed and added to the water.
Also, for what it is worth, I found Giardia and cryptosporidium in every stream I tested, including streams in protected watersheds (pristine forests that the public is not allowed in to protect water quality). My results were similar to those of other reasearchers such as Ongerth and Le Chaviler.
-
Haven't seen it since.
-
Just checked out the report on MVS's Web site. Those are some of the nicest photos I have seen in a Web climbing report. Just awesome.
-
No, I was looking for a house trained pet.
-
My wife and I are looking to adopt a dog and I ran across one named trask in a pet adoption Web site. I had to post it. I thought it was pretty funny. If I had run across a dog named lambone I would have posted that instead. I suppose animal cruelty laws prevent people from naming pets lambone though.
-
-
Just got back from Alaska. I had a couple of Aliens freeze on Mt Barille. Had to manipulate the cams by hand to contract them, then set them hard to make sure they engaged the rock. Never seen that happen with a cam before.
-
Dustin,
I have a medium size tricam (dark blue), never used which I give to you. I will even pay to mail it to you. email me: bighurtbob@hotmail.com
-
What I'm wondering is how did Colin get so damn good?
Colin was born good.
-
Good topic Juan,
I blame it all on Colin.
He makes it all look so effortless (soloing both the NE Couloir on Colchuck and Triple Couloirs in a day!) and the punk ass is not even out of high school yet! Much like supermodels effect on teenage girls he is setting an impossibly high standard for the rest of us. I vote we ban him from CC.com. He'll be the end of us all.
(BTW Colin, I'm headed to Alaska and there is a free plane ticket in it for you if you do all the leading. )
-
Some quarry near my friends house in 8th grade, free solo. So scared I thought I would puke. At least third class, maybe easy forth.
My new article
in Climber's Board
Posted
I am on the verge of posting an article that will dispel the popular notion that driving without wearing a seat belt is dangerous.
Among my evidence is the fact that literally millions of people drove on America's highways last year without having an accident. I also reference my neighbor, Bob, who says that he has been driving for years without an accident. I mayself have ridden in cars for 34 years and have never had an accident. Yet the authorities have made it a law to wear a seat belt! Most people who have accidents while not wearing seatbelts are easily treated in hospitals. I will publish my article in the Journal of kmurray Has a Huge Stick Up His Ass.