Moss on roof

That could be due to piss.

Medical studies with enough participants to be useful are expensive. You'll only get the funds if someone stands to benefit financially from it. That only happens when the study conclusion promotes their patented product. Hence studies mostly don't get done for unpatentable drugs & processes.

NT

All the above are very common. IM observation the NHS are too often shockingly incompetent & careless.

I?ve tried two methods. Waiting until a long dry spell then brushing (I can walk on our roof) and a power washer.

The former is hard work, especially as it is generally hot, the power washer is very messy but much easier.

It's true about bringing a drug to market. But if you are testing a physical intervention which is a normal activity or an effect of diet involving normal food you don't need toxicity and safety trials. Neither do you have to complete prescribed safety and efficacy studies. So if there is convincing anecdotal evidence a charity or a university department may fund a study on relatively small numbers to see if a positive effect can be identified. For diet, observational studies, with all their disadvantages of proper control and confounding, may be preferred to interventions as, unfortunately, few people will stick to a dietary restriction or addition for more than a few days even if they promise to.

In the area of medicine in which I am most involved, some of the absolute basics have never been properly assessed.

In the 1950s synthetic medicines became available and, over the next twenty or so years, the former animal-based medicines were effectively phased out. Yet there is not one single research paper which showed this to be safe, effective or desirable. (Except on grounds of cost.)

Even now, there is next to no direct comparison and the very few bits of research seem to show some benefit to the animal-based medicine but are dismissed as only the patients' opinion - nothing really measurable.

Ferrous Sulphate is my favourite for moss. It is dead (but black and unsightly) within a few hours. But you'd have to somehow spray it all over the roof.

What I'm about to say isn't intended to be critical of the doctors etc who prescribe drugs etc.

I've noticed on a couple of occasions, there is an element of 'try this first, it generally works'. If it doesn't, they work down a list, based on a mix of collective and personal experience until, hopefully, they find a drug, or combination, that either works or at least helps.

That may sound like they are fubbling in the dark but I see it another way. Firstly, our (as in the collective of human knowledge) understanding of how bodies work etc is anything but complete and different people, for a variety of reasons, react in different ways, are sensitive to certain drugs, conditions, etc. A doctor, faced with someone presenting a set of symptoms, perhaps verbally, has to make his best assessment on a way forward - tests may be available to help etc.- but, whatever the dataset he has it will never be complete or perfect.

Sometimes the 'holes' in the data won't make a difference in real terms, in others they will result in side effects, the treatment not working, or even something more serious.

Provided the Doctor has made the best (for some definition of best) decision - perhaps what most others would have done- then they can't really be blamed.

I'm not naive enough to suggest there aren't incompetent doctors - some cases that are reported are quite frightening- but others, where doctors have been, in my view, incorrectly blamed are due to either wider issues or people not accepting that our (ie the collective knowledge referred to above) understanding of the human body is anything but complete.

A prime example is the female doctor who was pilloried following the death of a child. Many of her colleagues rightly in my view pointed out, in the same position, they could well have acted as she did. The problem there was a systematic failure for which she carried the can.

Do you know if it is toxic when it gets into the soak away etc? I'm not suggesting it is- I collect water from part of our roof to water the garden etc.

I believe it is used to treat anaemia, so certainly not toxic in small doses :-) If watering the garden with it, note that if sufficiently concentrated, it will tend to noticeably iron stain light paving stones and similar things.

No, in low concentrations such as you'd get in your water butt it's not toxic to plants. In fact it's one of the chemicals recommended for acidifying soil when wanting to grow lime-hating plants such as rhododendrons, or for 'bluing' hydrangea flowers.

Excellent, thank you.

Thank you.

Mainly the water is used for the green house and veg etc.

That being said, it's rare (but not unheard of) for a patient to attend their GP about a condition which develops into an emergency while they are there.

As an aside, I had heard Copper Sulphate also worked and had assumed the copper wire trick was a variation on that- possibly due to a reaction with sulphides in rain but hadn't looked into further.

Is there as much sulphur in the air as there used to be ? Haven't heard about acid rain for a while ...

I expect it is the copper ions in solution that are important, not the sulphate. So whater the corrosion process, perhaps involving water, oxygen and CO2, some copper will diffuse about the tiles when damp.

I see it ion yet another way.

teh docor foillows an algorithim liek this

That is very big with doctors.

In te case of a friend of mine, her son died and was partially resuscitated - about half a brain was left - in A & E waiting to be seen. (he lived another 12 years or so with about the same consciousness and behaviour as a very unruly terrier).

The high court held that, since he had not been seen, no one could be held negligent.

A family friends sister died 15 years ago. She was 35, and went to A&E several times with an increasingly agonising abdominal pain. Each time she was told it was constipation and given stronger laxatives. Until she was blue-lit in. Turned out to be an ectopic pregnancy and she died as she was being admitted.

Now I am not a doctor - nor a surgeon. I don't even have a St. Johns ambulance badge (although I do have a pool lifeguard qualification). But even I know that "woman of child bearing age" = "check for pregnancy whatever the patient says". But it seems several *doctors* had a collective brain fart and forgot what should be day one stuff.