Science – Page 315 – David Bradley

Red eye removal

A neat way to remove the old red eye problem when you’ve taken a portrait with your camera’s built-in flash and the subject was staring right at the camera, is to paint it away. Unfortunately, this can be less than realistic because the catchlight and other details in the eye are lost.

Instead, of simply blasting black into the eye, use a
soft brush set to ‘color’ mode and set the brush color to black. Then carefully paint over the red-eye area to remove it. This desaturates the area you painted over without loss of detail in the eye. You might want to then use the “burn” tool to darken the pupil a little more to produce an even better result.

The catchlights in the eye and any other gradations are retained with this red eye removal technique – results in a much more natural look than those automatic red eye removal tools in iPhoto and other programs.

Sometimes the red eye flash back from the retina spills over into the iris too. You hopefully know what colour your subject’s eyes are normally so set the foreground colour to that hue rather than black (if you have a photo of them without red-eye use the dropper tool to grab the color) and with a soft and suitably sized brush set to “color” mode once more, paint over the iris area with this color. Results may vary and you may want to use masks and layers and all that other stuff to help you get the most natural and authentic look. Obviously, none of this is automatic, but then who wants automatic photography?

I’m proud to say that this tip was featured in Geoff Lawrence’s flash photography tutorial from whom we’ve borrowed the thumbnail of the red-eye girl above.

Citrus Compound Cuts Cholesterol

It’s old news now, but a recent visitor to Sciencebase hit the site searching for citrus PMFs, so here’s a link to the information they were probably after: Compound found in the peel of citrus fruit can potentially lower cholesterol more effectively than some prescription drugs, at least if you’re a hamster.

According to multiple media reports, “US scientists fattened up hamsters on a high-cholesterol diet, and then fed them compounds found in tangerine and orange peel. They found the compounds significantly lowered the animals’ levels of LDL cholesterol – which is associated with heart disease.”

The compounds in question are a kind of antioxidant known as polymethoxylated flavones (PMFs).

Diagnose-it-Yourself

Almost every minor symptom seems to be tied to a deficiency in some mineral or micro-nutrient or other, according to the Body Language site. I’ll leave visitors to check into the affiliations of the website, in case they’re simply touting supplements, although I don’t think they are.

Meanwhile, a taster, as it were:

Muscle cramps, calf tenderness, hypertension? – Magnesium

Wheezy after fruit/veg/wine? – Molybdenum

Stretch marks? – Zinc

Vitiligo/premature grey hair? – PABA and magnesium

Evacuation not best during a chemical incident

According to New Scientist this week, evacuation is not the best course of action during a chemical incident. Sheltering at home may be better than evacuation for residents living in an area during a chemical incident. So says a study of a real emergency situation that occurred in 1999 when a serious fire broke out in a plastsics factory in Devon, UK.

Ironically, it’s probably the only good reason for installing hermetic plastic-framed double glazing and doors in an otherwise authentic Devon cottage. I’m not sure what the building conservation organisations would have to say about that, but if we didn’t all install those uPVC window frames that potentially hazardous plastics factory maybe wouldn’t be there in the first place. Admittedly, we’d have to go for nice wooden frames instead, with their attendant environmental concerns, and repeated painting with noxious gloss paint! You can’t win.

Study: Genistein in soya may harm male fertility

I found an interesting write-up of that soy and sperm story I blogged yesterday: Genistein in soya

The author makes a similar point to me: “The study does not reveal how genistein would affect in vivo human sperm.”

But, then he says, “In reality, Asian people use a lot of soya products, but they don’t seem to have a fertility problem.” What does he mean “in reality”? As opposed to “in the laboratory?”, “in virtuality?”, “on TV?”, what? Anyway, how does he know that Asian people don’t suffer fertility problems, is he assuming that because the populations of Asian countries are high that individuals are fecund?

Anyway, back to the science – the isoflavone genistein has been shown in separate studies to have estrogenic and anti-estrogenic properties and also to be a cancer protective. But, then others have shown it to cause uterine cancer…I don’t suppose we’ll ever know the truth, especially given that much of the research into the health benefits of soya products has been funded over the years by soya manufacturers.

Soybean Sperm Assassin

According to the BBC today, soybeans, peas, and French beans can affect fertility. Apparently, women shouldn’t eat these leguminous veggies because they can damage sperm. Surely it should be men that ought to avoid these vegetables…or is it that eating them releases something into the female reproductive tract that seeks and destroys sperm? The BBC didn’t say.

One thing that should be pointed out is that the researchers in question have only demonstrated the effect in the laboratory, said The Beeb. I reckon those researchers ought to be more careful about what they get up to in their lab, testing out their fertility on each other…

One other thing, before I go, according to http://www.nulldrweil.com/u/QA/QA89074/ if you’re undergoing IVF then both partners need to up their zinc intake and guess what he cites as the best vegetarian sources of Zn…legumes (dried beans, garbanzos, black-eyed peas, lentils, peas, soy products and whole grains).

Talk about conflicting evidence.

Joni Mitchell would be turning in her grave

US researchers (Geological Survey and the City of Austin (Texas)) has discovered that runoff from the shiny coating, sealcoat, they apply to asphalt car parks is a previously unrecognized source of polycyclic aromatic hydrocarbons (PAHs). The study is online today (June 22) in Environmental Science and Technology. Is this yet another justification for reducing car use, or environmental whinging? You decide.

Is there a material that blocks magnetic forces?

A hit on my sciencebase article about frustrated magnets came about through a visitor searching Yahoo! for “material that blocks magnetic forces”.

Physlink provides a nice answer to the question of whether a “magnetic insulator” exists. The simple answer is no: Is there any material that can block a magnetic force?

Lead certainly doesn’t do it, and it’s all because of Maxwell’s Equation. You can of course re-route a magnetic field and supposed shielding materials exist.

Orgasms fill the news

Orgasm seems to be the hot topic for science news this summer. We had the genetic basis of female orgasm a couple of weeks ago and now The Register is reporting how women’s brains switch off when they are brought to orgasm by their partner. How can they tell? Bedside MRI apparently. So if you have a few million dollars to spare, says the naughty little publication, you can spot a fake.

A cup of hot tea does not cool you down

nice-cup-of-tea At the time of writing, the UK was in the middle of a rare heatwave, and my mother, as usual, suffers when the mercury rises about 25 or so (it’s 33 here today!) and, as usual, is suggesting everyone has a nice cup of hot tea to help them cool down.

Of course, it is easy to mock the underlying physics of such a suggestion (Does Hot Tea Really Cool You Down?), and I have explained to my mother that it’s a myth, but such conventional wisdom seems to persist and someone only this morning visited the sciencebase site searching for an answer to the question, does hot tea cool you down? Or more generally “does a hot drink cool you down?” Someone, even asked the presumptuous question: “Why does drinking hot drinks cool you down?”

Bluntly, no.

However, even as a hot drink, it can make you feel refreshed even when the air is still and humid and as long as you don’t gulp it down too quickly it won’t make you even more sweaty. I guess there may be a psychological effect, if the air is warm and humid and you drink something hot, that will heat you up more and make you sweat, sweat evaporates from your skin cooling your skin, so maybe you end up feeling slightly cooler, but I’m still not convinced. In fact, sweating inflames the skin in some ways as capillaries open up and you actually feel hotter when you sweat more, unless you’ve got a very strong fan. Anyway, from the thermodynamics point of view adding a hot liquid to a cooler container (your body) will raise the temperature of the container.

Now, iced tea is a different matter – make mine a peach one! And, plenty of ice!

Of course, there’s also this well-known 19th century quotation from Gladstone

If you are cold, tea will warm you. If you are too heated, it will cool you. If you are depressed, it will cheer you. If you are excited, it will calm you.

For more on teatime etiquette, check out this item.