Bbrhuft t1_jcfhm3b wrote

Lead-214 has a half life of 27 minutes, you're thinking of Lead-210.

Radon-222 -> Po-218 + Alpha (3.8 days)

Po-218 -> Pb-214 + Alpha (3.1 minutes)

Pb-214 -> Bi-214 + e^(-) (27 minutes)

Bi-214 -> Po-214 + e^(-) (19.7 minutes)

Po-218, Pb-214 and Bi-214 are the most important radon daughters, they are responsible for most of the (indirect) radiation dose from Radon-222.

Pb-214 and Bi-214 are also ions, singly ionized.

Also, the Po-214 daughter travelling at 13 million miles per hour, recoil from kicking out a Alpha particle at 8% the speed of light.


Bbrhuft t1_jcffirz wrote

He was correct. Lead oxide isn't formed.

There's several factors that need to be considered. The fact that the Lead-214 daughter is singly ionized so reactions with oxygen aren't favoured, that air is humid and is often contaminated with VOCs and SO2, especially indoor air, and the fact that these reactions take place within an ionization trail generated by the Alpha particle, that generates hydroxy radicals from atmospheric humidity and NO2 (the radon daughter atoms recoil at 10-13 million mph btw).

Instead, Lead-214 will most often form tiny clusters surrounded by 5 to 8 water molecules and likely often a few molecules of VOCs. They measured the size of the clusters, they average 1.2 - 2 nm in diameter. Po-218 is a little different, it forms larger 15 nm clusters additionally with SO2 (once air contains a few ppm of SO2) and as, well as much smaller clusters of PoOx 0.5 - 1 nm in diameter (the proportion of these clusters depends on what's in the air).

Castleman Jr, A.W., 1991. Consideration of the chemistry of radon progeny. Environmental science & technology, 25(4), pp.730-735.

Hopke, P., 1996. The initial atmospheric behavior of radon decay products. Journal of Radioanalytical and Nuclear Chemistry, 203(2), pp.353-375.


Bbrhuft t1_jcfday0 wrote

One important consideration is the fact that Lead-214 and Bismuth-214 are electrically charged, singly ionized ions. The other factor that needs to be taken into account is the fact that these reactions occur within an ionization trail that contains hydroxyl radicals and NO2 (the Alpha particles are ejected at 7-8% the speed of light, and the daughter atoms recoil at 10 to 13 million mph). And the final factor that make all this more complex that single atoms floating in nitrogen and oxygen is the fact that air isn't pure, but is often contaminated with volatile organic compounds, particularly indoor air, and SO2.

As a result Lead and bismuth oxide isn't formed. They form clusters of 5 to 8 water molecules and often a few molecules of VOCs. They were measured experimentally, and are 1.2 - 2 nanometers in diameter.

Po-218 is a little different, it can form larger clusters about 15 nm that additionally contain SO2 (if air contains a few ppm of SO2, common in urban and inner city environments), and water molecules. It can also form much smaller clusters of PoOx, 0.5 - 1 nm.

I think I've summarize what I read correctly.


Castleman Jr, A.W., 1991. Consideration of the chemistry of radon progeny. Environmental science & technology, 25(4), pp.730-735.

Hopke, P., 1996. The initial atmospheric behavior of radon decay products. Journal of Radioanalytical and Nuclear Chemistry, 203(2), pp.353-375.


Bbrhuft t1_jcdzt3r wrote

The radon progeny, Bi-214 and Pb-214 do not react with oxygen, except sometimes Po-218.

They start off are singly ionized ions (Po+, Pb+, Bi+). As a result, reactions with Volatile Organic Compounds (VOCs), which commonly contaminates air, especially indoor air, is favoured over oxygen. They also react with hydroxyl radicals, ionized water vapour that's formed in the ionization trail of their recoil path (Po-218 recoils at 13 million mph, after Radon-222 emits an Alpha particle travelling at 7% the speed of light).

These reactions form minute particles, 1.2 to 2 nm in diameter, likely consisting of clusters of 5 to 8 water molecules and a few molecules of VOCs surrounding a now neutral atom of Pb or Bi.

That said, some Po-218 ions react to form Po oxide. This is shown by a double peak in measured particle size distribution of radon Po progeny particles; Po forms a double peak, smaller particles of PoOx of 0.5 - 1.5 nm and much lager particles (c. 15 nm) of a Po atom surrounded by SO2, water and VOC molecules much larger than Bi-214 and Pb-214 clusters.

Castleman Jr, A.W., 1991. Consideration of the chemistry of radon progeny. Environmental science & technology, 25(4), pp.730-735.

Hopke, P., 1996. The initial atmospheric behavior of radon decay products. Journal of Radioanalytical and Nuclear Chemistry, 203(2), pp.353-375.


Bbrhuft t1_jcdxda3 wrote

Po-218, Lead-214 and bismuth-214 are singly ionized ions. Since they are singly ionized, reactions with oxygen are not favoured, they are instead predicted to hydrolyse with hydroxyl radicals and with trace Volatile Organic Compounds (VOCs) that often contaminate air, indoor air in particular.

Also, you must consider the effects of the radiation and kinetic recoil of the ions, their velocity, c. 10-13 million mph for Po-218 ions after they emit an Alpha particles at 7% the speed of light. Lead-214 and Bismuth-214 also form in ionization trails, generated by Beta particles. As a result, chemical reactions, and thus neutralization of the ions, take place with hydroxyl radicals generated from ionized water vapour, and also, likely NO₂.

The reaction products of radon progeny grow and form ultrafine particles, 1.2 to 2 nanometres in diameter, these likely consist of 5 to 8 molecules of water and a few molecules of VOCs. These stick to dust or settle on solid surfaces, i.e. radon progeny plate out.

>The chemical and physical properties of 218Po immediately following its formation from 222Rn decay are important in determining its behavior in indoor atmospheres and play a major part in determining its potential health effects. In 88% of the decays, a singly charged, positive ion of 218Po is obtained at the end of its recoil path. > >These ions can interact with water vapor or other volatile organic compounds (VOCs) that may exist in indoor air. > >The ions can be neutralized by 3 different mechanisms, small-ion recombination, electron transfer, and electron scavenging. In typical indoor air, the ion will be rapidly neutralized by transfer of electrons from lower ionization potential gases such as NO2. > >The neutral molecule can then become incorporated in ultrafine particles formed by the radiolytic processes in the recoil path. These particles will typically be formed by the presence of the air ions produced by the passage of the emitted α-particle through ion-induced nucleation. > >In addition these energetic ions can react with water molecules to produce hydroxyl radicals. > >Thus, the decay of the radon nucleus produces a variety of effects and can result in changes in the size of the radioactive species that includes the radon progeny.


Castleman Jr, A.W., 1991. Consideration of the chemistry of radon progeny. Environmental science & technology, 25(4), pp.730-735.

Hopke, P., 1996. The initial atmospheric behavior of radon decay products. Journal of Radioanalytical and Nuclear Chemistry, 203(2), pp.353-375.


Bbrhuft t1_jcayi93 wrote

Wow, so it's biologically concentrating Po-210 like how Chernobyl mushrooms concentrate Cesium-137, or radioactive galena...

This will interest you. Here's a sample of radioactive galena I have from the Kateřina Coal Mine, Radvanice, Czech Republic.

Here's a close up photo...

It looks like a bismuth specimen, due to its odd formation process, deposition from hot gas.

The Kateřina Coal Mine was a bizarre combination of a coal and uranium mine, that caught fire in the 1960s or 70s. Fumes from the burning coal seams deposited galena in cracks, which ended up contaminated with radioactive Lead-210, half life 22 years.

The specimen was likely collected in the 1990. The entire site was rehabilitated about 15 years ago, it's now a nice green park. Big difference from the hell scape of a burning radioactive coal mine.


Bbrhuft t1_jcaunob wrote

That's interesting. I always wondered where the Polonium-210 came from. I have a radioactive apatite from Brazil. In this case it contains radioactive thorium, but yes apatite (phosphate ore) can also contain uranium.


Bbrhuft t1_jcat9ql wrote

Radon Daughters stick to dust at ground level and that dust is carried into the higher atmosphere by rising air currents, they can rain out when there's heavy rain, thunderstorms particularly, a phenomena called Radon Washout.

It was discovered by accident in the 1960s. A nuclear worker walked though puddles in a car park on the way to work, and he set off the alarms as he arrived, since that's backwards they were intrigued, and they discovered that atmospheric dust is coated with radon daughters which can get concentrated in electrically charged thunderstorms, and rain out as Radon Washout.

Radon Washout can sometimes be intensely radioactive, and there's a paper that estimated that a few percent of skin cancers might be linked to Radon Washout, beta radiation from Lead-214 and Bismuth-214 decay is able to penetrate the outer layers of the skin and deposit a radiation dose to living skin cells, a risk increased for people who work outdoors. This might be speculative, nevertheless, it illustrates just how radioactive rain can be sometimes be when weather conditions are just right.

I measured it myself a few times. Got readings up to 2 microsieverts per hour, nothing spectacular.

Styro, B.I. and Stelingis, K.I., 1978. On the value of flow of long-lived radon-222 decay products into atmosphere with the dust of natural and anthropogenic origin. In Chemical and radioactive pollution of the atmosphere and hydrosphere. V. 4.

Edit: Also, >90% of indoor radon daughters are bound to dust, very little is unbound, free floating.


Bbrhuft t1_jcamrpd wrote

Having high radon levels in a basement area, a little above the recommended levels, shouldn't be a problem as you don't spend much time there, unlike a bedroom or living room.

Also, if you have a clothes drier in your basement and a Geiger Counter, a fun experiment involves measuring the radioactivity of the lint caught in the dust trap. It can sometimes be extraordinarily radioactive.

It doesn't work for me, as my clothes dryer is in a well ventilated room.

Also, the most effective way for society to reduce the risk of lung cancer from indoor radon exposure is to reduce rates of tobacco smoking.

Most people who get radon linked lung cancer are current and former smokers, as smoking reduces the lung's capacity to repair DNA damage caused by ionizing radiation. Smokers are almost 9 times more likely to develop radon linked lung cancer than never-smokers.

>The BEIR VI model also purports a significant synergism between radon exposure and smoking in lung cancer risk. On the basis of BEIR VI, the EPA estimates that, at a radon level of 4 pCi/L, the lifetime risk of radoninduced lung cancer death for never-smokers is 7 per 1000, compared with 62 per 1000 for ever-smokers.

Lantz, P.M., Mendez, D. and Philbert, M.A., 2013. Radon, smoking, and lung cancer: the need to refocus radon control policy. American journal of public health, 103(3), pp.443-447.


Bbrhuft t1_jcajnfa wrote

FYI. have a radium dial compass sealed inside an air tight jar, safely stored in an unoccupied room. It's highly radioactive, back then Zinc sulfide phosphor wasn't particularly sensitive so they compensated by adding extra radium.

Anyway, the interior of the jar gets coated with radon daughter plate out:

This is the decay I measured, due to Bismuth-214 and Lead-214 decay.

Anyways, the contamination stubbornly adhers to the glass. I tried rubbing it off with tissues, dampened with water and alcohol. I estimate I can remove about 25% of the contamination, by measuring the radioactivity on the tissue, most remains stuck to the glass.

Radon Plate Out occurs because the decay products (218Po, 214Pb and 214Bi) are electrically charged, they are attracted to dust and surfaces that are slightly charged.


Bbrhuft t1_jcahqgc wrote

Yes, Po-218, Lead-214 and Bismuth-214 are electrically charged, as a result they tend to stick to dust particles and solid surfaces that are negatively charged, a phenomena called Radon Daughter Plate Out. Indoor air contains mostly (>90%) attached progeny, stuck to dust particles. Attached (Po-218, Lead-214 and Bismuth-214) progeny are responsible for most of the radiation dose from indoor radon.

Vogiannis, E.G. and Nikolopoulos, D., 2015. Radon sources and associated risk in terms of exposure and dose. Frontiers in public health, 2, p.207.


Bbrhuft t1_jcaeg0n wrote

Radon-222 decays via several steps, a decay chain leading to non-radioactive, Lead-210. A lot of the radon decay products, Lead-214 and Bismuth-214, ends up coating dust particles and sold surfaces, a phenomena called Radon Daughter Plate Out. So the daughter atoms aren't usually free floating in the air, but usually more than 90% ends up sticking to dust particles and solid surfaces.

>A small fraction of radon progeny, typically 0.1 or less, remains unattached and in dynamic equilibrium with attached particles. Generally, dustier atmospheres are associated with smaller values of unattached fraction and higher concentrations of radon due to additional radiation emission from dust.

This is the decay chain for Uranium-238, which includes Radon-222

Radon-222 initially decays to Polonium-218, via emitting a positively charged Alpha particle. The resulting Polonium-218 atom, with a half life of 3.1 minutes, is electrically charged and it is attracted to charged dust particles and sold surfaces where it quickly decays to Lead-214 and Bismuth-214, formimg a radioactive coating, a major source of radiation exposure from indoor Radon gas.

These two isotopes, in comparison to other isotopes of the randon decay chain, have relatively long combined half life of just over 20 minutes.

Radon Plate Out can be demonstrated using a balloon. If you have a building or better still, a basement with a slight radon problem, and leave an electrically charged balloon in the room for an hour or so, then measure it with a Geiger Counter, you'll often find the balloon becomes radioactive due a coating of Lead-214 and Bismuth-214, from attracting Polonium-218 directly and radioactive dust particles.

The Plate Out on glass is very sticky, I keep a Radium dial WWII compass safely sealed in an air tight jar. The inside of the jar gets coated with radon plate out, rubbing the glass with a wet tissue removes some of the contamination, the tissue gets contaminated, but most of the activity is stays stubbornly stuck to the glass.

It's possible some of plate out might have formed some sort of electrostatic bond, perhaps Van Der Waals force.

I can also measure the decay of the contamination:

The isotopes have an average half life of just over 20 minutes, so it's decay noticed quite quickly (using a Radiascan 701a connected to logging software on my PC).


Bbrhuft t1_jbfl2dd wrote

There was a 1990s theory that the centre of the Earth's core was natural uranium nuclear reactor that provided a some of Earth's internal heat, possibly helped drive the Earth's magnetic field. This extraordinary theory was proposed by J. Marvin Herndon who published a fantastical paper in 1993 claiming that he inner core was was composed of natural uranium and it was a natural fission reactor, a georeactor.

The idea was supported by plausible, at the time, geochemistry, that appeared to suggest that uranium could differentiate from iron-nickel and form an inner uranium core at the center of the Earth. However, most at the time disagreed, said the uranium content wasn't high enough to form a uranium core and/or the chemistry at high pressures prevent the separation of uranium from other metals.

Also, futher, advances in geoneutrino detection, that's neutrinos emited by radioactive decay and hypothetical inner core fission, ruled out a fission reactor well below the energy output proposed by J. Marvin Herndon.

Didn't stop him promoting the idea however, of a weaker fission reactor, or one that was more active in the past when there was more fissionable 235U.

Also, there's other scientists, who proposes variations on the Core Fission Hypothesis. A recent claim proposed a uranium oxide fission reactor at the inner/outer core boundary. This was published in a reputable journal. They proposed a 30 TeraWatt georeactor. That's insane.

I must look into this more, at it seems some scientists seriously think this is possible.


Herndon, J.M., 1993. Feasibility of a nuclear fission reactor at the center of the Earth as the energy source for the geomagnetic field. Journal of geomagnetism and geoelectricity, 45(5), pp.423-437.

Rusov, V.D., Pavlovich, V.N., Vaschenko, V.N., Tarasov, V.A., Zelentsova, T.N., Bolshakov, V.N., Litvinov, D.A., Kosenko, S.I. and Byegunova, O.A., 2007. Geoantineutrino spectrum and slow nuclear burning on the boundary of the liquid and solid phases of the Earth's core. Journal of Geophysical Research: Solid Earth, 112(B9).


Bbrhuft t1_jaqvrni wrote

Absolutely true. One interesting overlap is with Prolapsed Mitral Valve, a common and usually mild heart abnormality, which can cause heart palpitations. A connection between people with PMV, panic disorder (PD) and hypermobility was notice many years ago. I'm once such example.

>The prevalence of MVP in PD and healthy controls was 27.20% and 9.21%, respectively. Patients with PD had a significantly increased relative risk of MVP compared to controls in the pooled sample (RR = 2.469, 95% confidence interval = 1.848–3.300). Age did not significantly modify the RR.

Also, I'm multiply cursed, ASD, ADHD, Prolapsed Mitral Valve, hypermobile joints, and panic attacks so bad in my teenage and early adulthood, that I could have represented my country at the panic attack Olympics. Thankfully I got over them.

Tural, U. and Iosifescu, D.V., 2019. The prevalence of mitral valve prolapse in panic disorder: a meta-analysis. Psychosomatics, 60(4), pp.393-401.

Garcia-Campayo, J., Asso, E. and Alda, M., 2011. Joint hypermobility and anxiety: the state of the art. Current Psychiatry Reports, 13, pp.18-25.


Bbrhuft t1_jaeqkyn wrote

This is a mass psychogenic illness, the physical manifestation of the damaging psychological effects of living under a despotic regime that devalues women, poisons their mental health as effectively as a physical poison gas, but unlike a gas, it lasts a lifetime.


Bbrhuft t1_jaeekf4 wrote

  1. Blackburn faintings (1965) – In October 1965, several girls at a girls' school complained of dizziness in Blackburn, England. Some fainted. Within a couple of hours, 85 girls from the school were rushed by ambulance to a nearby hospital after fainting. Symptoms included swooning, moaning, chattering of teeth, hyperpnea, and tetany. A medical analysis of the event about one year later found that outbreaks began among the 14-year-olds, but that the heaviest incidence moved to the youngest age groups. There was no evidence of pollution of food or air. The younger girls proved more susceptible, but disturbance was more severe and lasted longer in the older girls. Using the Eysenck Personality Inventory, those affected had higher scores for extroversion and neuroticism. It was considered that the epidemic was hysterical, that a previous polio epidemic had rendered the population emotionally vulnerable, and that a three-hour parade, producing 20 faints on the day before the first outbreak, had been the specific trigger.

  2. In May 2006, an outbreak of the so-dubbed Morangos com Açúcar Virus ('Strawberries with Sugar virus') was reported in Portuguese schools, named after the popular teen girl's show Morangos com Açúcar ('Strawberries With Sugar'). At least 300 students at 14 schools reported similar symptoms to those experienced by the characters in a then recent episode where a life-threatening virus affected the school depicted in the show. Symptoms included rashes, difficulty breathing, and dizziness. The belief that there was a medical outbreak forced some school to temporarily close. The Portuguese National Institute for Medical Emergency eventually dismissed the illness as mass hysteria.

  3. Mexico City (2006–2007) – Between October 2006 and June 2007, near Chalco, a working-class suburb of Mexico City, mass hysteria resulted in an outbreak of unusual symptoms experienced by more than 500 adolescent female students at Children's Village School (Villa de las Ninas), a Catholic boarding-school. The affected students had difficulty walking and were feverish and nauseated, some becoming partially paralyzed.

  4. Mexico City (2006–2007) – Between October 2006 and June 2007, near Chalco, a working-class suburb of Mexico City, mass hysteria resulted in an outbreak of unusual symptoms experienced by more than 500 adolescent female students at Children's Village School (Villa de las Ninas), a Catholic boarding-school. The affected students had difficulty walking and were feverish and nauseated, some becoming partially paralyzed.

  5. Vinton, Virginia (2007) – An outbreak of twitching, headaches and dizziness affected at least nine girls and one teacher at William Byrd High School. The episode lasted for months amid other local public health scares.

  6. Tanzania (2008) – In September 2008, 20 girls at a school in Tabora started fainting while taking their final year exams. The mass fainting has been linked to neurosis related to the local practice of witchcraft

  7. Afghanistan (2009–) – Starting around 2009, a spate of apparent poisonings at girls' schools across Afghanistan began to be reported, with symptoms including dizziness, fainting, and vomiting. The United Nations, World Health Organization and NATO's International Security Assistance Force carried out investigations of the incidents over multiple years, but never found any evidence of toxins or poisoning in the hundreds of blood, urine, and water samples they tested. The conclusion of the investigators was that the girls had a mass psychogenic illness.

  8. Brunei (2010) – In April and May 2010, incidents of mass hysteria occurred at two all-girls secondary schools in Brunei. The most recent notable event happened on the 24 April 2014 in a public secondary school. The phenomenon caused a wave of panic among many parents, educators, and members of the community. Some of the students affected by the phenomenon claimed to have been possessed by spirits, or jinn, displaying histrionic symptoms such as screaming, shaking, fainting, and crying.

  9. Le Roy, New York (2011–12) – After 12 high school girls developed Tourette-like symptoms in 2011, their school was tested for toxins, and all other factors for their symptoms were ruled out. The case, and some of the girls and their parents, gained national media attention. In January 2012, several more students and a 36-year-old adult female came forward with similar symptoms. They were all diagnosed with conversion disorder.

  10. Sri Lanka (2012) – From November 15–20, 2012, incidents of mass hysteria occurred at 15 schools in Sri Lanka. More than 1,900 school children of 15 schools in Sri Lanka and five teachers were treated for a range of symptoms that included skin rashes, vomiting, vertigo, and cough due to allergic reactions believed to be mass hysteria. It originated at the Jinaraja Balika Vidyalaya in Gampola on November 15, 2012, when 1,100 students were admitted to hospital with a range of symptoms that included skin rashes, vomiting, vertigo and coughing. Later, authorities had to close down the school for 3 days.

  11. Recurrent epidemic of mass hysteria in Nepal (2016–2018) – A unique phenomenon of “recurrent epidemic of mass hysteria” was reported from a school of Pyuthan district of western Nepal in 2018. After a 9-year-old school girl developed crying and shouting episodes, quickly other children of the same school were also affected resulting in 47 affected students (37 females, 10 males) in the same day. Since 2016 similar episodes of mass psychogenic illness has been occurring in the same school every year. In 2016, twelve students were affected and in 2017, a total of 18 students of the same school were affected showing various symptoms in a single day. Hence it was thought to be a unique case of recurrent mass hysteria.

  12. Ketereh, Malaysia (2019) – In August 2019, the BBC reported that schoolgirls at the Ketereh national secondary school (SMK Ketereh) in Kelantan, started screaming, with some claiming to have seen 'a face of pure evil'. Professor Simon Wessely a former president of the Royal College of Psychiatrists, suggested it was a form of 'collective behaviour'.

  13. Starehe Girls' Centre, Kenya (October 2019) – 52 students were isolated with an unknown disease, showing symptoms of a high-pitched cough, sneezing and low-grade fever, a number that later rose to 68. As the number rose, the school's administration shut the school down and instructed parents to pick up their daughters. Specimens collected from the affected students showed only two cases of rhinovirus, a virus that is the predominant cause of the common cold. After carrying out psychological assessments on the students, a team of mental health specialists dispatched by Kenya's Ministry of Health to the school concluded that the 'mysterious' disease was a case of mass hysteria.


Bbrhuft t1_j9ew86u wrote

I see 4.9% of 555 newly diagnosed HIV infections in France between 2003-10, were the CXCR4-tropic variant. And of these, 1.5% were involved in a transmission clusters (one case).

I think it means the CXCR4-tropic variant usually arises/evolves after infection, it's less often involved in transmission?

I think they hypothesize, if I understand the paper correctly, that the CXCR4-tropic variant is less infectious than CCR5 variants.

Frange, P., Meyer, L., Ghosn, J., Deveau, C., Goujard, C., Duvivier, C., Tubiana, R., Rouzioux, C., Chaix, M.L. and ANRS CO6 PRIMO Cohort Study Group, 2013. Prevalence of CXCR 4‐tropic viruses in clustered transmission chains at the time of primary HIV‐1 infection. Clinical Microbiology and Infection, 19(5), pp.E252-E255.


Bbrhuft t1_j94vg4h wrote

Just to point out that 56% of the population in the Donbas before the war identifed as Russian speaking Ukrainians while 34% identified as ethinic Russian.

The east of the country was ruled by the Romanovs in the 19th century, while west was part of Austro-Hungarian empire for a long time.

Ukranians in the Donbas started speaking Russian, much like how Irish people under British rule rapidly stopped speaking Irish and switched to English in the 19th century, but they didn't stop being Irish.

There was also an immigration of Russians beginning in the 18th century, that population movement increased in the early 20th century because the mines were looking for workers.

Basically, it wasn't as black and white as portrayed by Russian propaganda. Russian speaker doesn't always mean ethinic Russian.

Ukraine didn't go into the Donbas with the intention of ethically cleansing the region of Russians, as explained the situation wasn't black and white, as many identified as Russian speaking Ukrainians.

Russia installed a number of pro-Russian milita leaders, some like Strelkov (involved in shooting down MH17) came from outside, from Russia. Russia stirred up, instigated and suported a separatist movement that Ukraine tried to resist, that was covertly suported by the Russian army. Strange for farmers and miners to find so many T-72s lying around. And, when it seemed that the pro-Russian militas were going to loose, the Russian military secretly invaded Ukraine and routed the Ukranian army.


Bbrhuft t1_j91bx8b wrote

It's a bit of a mystery. However, the evolutionarily roots of iodine cell signalling is very acient, almost all all multicellular life uses iodine containing molecules, including plants.

A recent interesting hypothesis proposed that... Given that almost all multicellular life uses iodine containing cell signalling molecules, they must have evolved very early billions of years ago in early single celled organisms, and the development of multicellularity and iodine containing cell signalling molecules went hand in hand.

The reason why iodine was used, is that molecules that contain iodine are highly reactive and often powerful antioxidants, they are very useful.

Crockford, S.J., 2009. Evolutionary roots of iodine and thyroid hormones in cell–cell signaling. Integrative and comparative biology, 49(2), pp.155-166.


Bbrhuft t1_j51ith5 wrote

Here's the reference:

>Robertsonian translocations occur in approximately one in every 1000 newborns. Although most Robertsonian translocation carriers are healthy and have a normal lifespan, they are at increased risk of spontaneous abortions and risk of producing unbalanced gametes and, therefore unbalanced offspring. Here we reported a previously undescribed Robertsonian translocation.

Song, J., Sun, L., Xu, S., Liu, N., Yao, Y., Liu, Z., Wang, W., Rong, H. and Wang, B., 2016. A family with Robertsonian translocation: a potential mechanism of speciation in Humans. Molecular Cytogenetics, 9(1), pp.1-7.