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Magnetic Separation Method for Isolating Rare-Earth Elements and Zirconium from Molten Salts

The paper to which I'll briefly refer is this one, published by Russian scientists in an English edition: Alekseeva, L.S., Savinykh, D.O., Orlova, A.I. et al. Magnetic Separation Method for Isolating Rare-Earth Elements and Zirconium from Molten Salts. Inorg Mater 56, 583–590 (2020).

Strontium ferrites are magnetic particles that find utility in many electronic storage devices. This paper uses magnetic particles that are also strontium based, particles which apparently have a Curie Point higher than the temperature of molten salts.

From the introduction:

Pyroelectrochemical technology utilizing molten salts, primarily molten alkali chlorides, as solvents is commonly thought to have considerable potential. Pyrochemical processes are characterized by small volumes of waste, its high specific activity, and the near absence of liquid technological high-level waste. This technology has a number of advantages: melts are good solvents, they are stable at high temperatures and under irradiation, and the use of melts allows one to run the process without water, necessary for all living systems. Work with chloride melts, with application in pyroelectrochemical technology, has been and is being carried out in many countries all over the world: in Russia [1–7], the United States, Japan [8], Korea [9], and the United Kingdom [3, 10] (zeolite sorption). The behavior of U, Np, Pu, and Am in LiCl–KCl melts has been the subject of extensive studies [1, 11–25]. The diversity of studies, in particular, in recent years [20–23], indicates that this is a topical issue.

Extraction of actinides (Am and Cm), rare-earth elements (REEs), and zirconium from melts is one of the key issues in this technology, in particular in Russia [5, 6, 24, 25].

Extraction, preconcentration, and consolidation methods under development for subsequent isolation of actinide fission products from the biosphere include precipitation, ion exchange, zone crystallization, and sorption.

In this work, we propose using a magnetic field for extracting components dissolved in a LiCl–KCl melt.

Actinide- and rare-earth-containing strontium hexaferrite with the magnetoplumbite structure and zirconium-containing spinel ferrites are of interest as magnetic carriers capable of absorbing melt components to be extracted.

The authors synthesized spinel magnetic ferrite particles isomorphous with a magnetic mineral containing lead, magnetoplumbite. They noted that many of the compounds in this class of isomorphs can incorporate lanthanide elements (aka "rare earths."

However their spinel structure was a compound, again isomorphous, of strontium, copper, iron and oxygen.

They heated a molten salt composed of potassium and lithium chloride at 450C and were able to extract neodymium and zirconium.

It was hardly quantitative according to a table in the paper:

There are lots of people who are molten salt reactor kind of guys and gals; I used to be one myself, but I changed my mind. However, in recent years I have begun to rethink molten salts in all kinds of chemical separations processes, and redox processes, including but not limited to separation and recovery of valuable materials in used nuclear fuels. (It should be noted that there are an infinite number of molten salts, given the existence and wide study of "ionic liquids" some of which are partially or wholly organic molecules.

I'm not sure this work has much practical import, although one can imagine these things in certain kinds of molecular filters, but any magnetic material with a curie point high enough to be stable in a molten alkali metal salt is interesting. For the record, I do not favor the use of potassium salts in nuclear fuel settings since the separation from cesium is problematic. Rubidium, which is present mostly in a form (Rb-87) that occurs naturally all over the planet as a fission product is a better choice.

I trust you're having a nice Saturday.

I would say there's a especially wonderful "Greatest Threads" list today.

At a small country church

The doc is right

Calling my son a big fat chicken worked!

posted on jill biden's twitter yesterday (and i love this picture!)

"Let them stand up in the well of the floor, put on some Depends, let their feet bleed or whatever"

I found them uplifting: family, courage, honesty, strength...

I added a rec to each.

Thermoelectric Power Generation and Water Stress in India: A Spatial and Temporal Analysis

The paper I'll discuss in this brief post is this one: Thermoelectric Power Generation and Water Stress in India: A Spatial and Temporal Analysis (Chao Zhang, Joonseok Yang, Johannes Urpelainen, Puneet Chitkara, Jiayi Zhang, and Jiao Wang Environmental Science & Technology 2021 55 (8), 4314-4323).

The connection between water and energy, particularly in an electrified world is inexorable.

It is worth noting (or confessing?) that the form of electrical energy (and other) energy that I regard as sustainable and environmentally acceptable, nuclear energy, is the worst offender for the use of water for power generation, at least as presently practiced. I am convinced that this problem can be engineered away, but it has not, as of now, been engineered away.

The paper under discussion is an overview of the water situation in India, a developing nation now undergoing a terrible Covid tragedy for which all decent human beings must extend sympathy and where possible aid. This said, the long term, environmental tragedy of India may make Covid pale in the end. For this reason, this paper, a policy paper, is worth some consideration.

From the introduction:

Water and energy are inextricably linked since most types of power generating processes, and thermal power in particular, require a significant amount of water, especially for steam generation, ash-handling, and cooling. Similarly, energy is required for all phases of water processing, including extraction, treatment, transportation, and consumption.(1−3) However, climate change and the sharp increase in global water demand pose serious threats to the sustainable supply of these critical resources. This results in a high degree of interdependency in a self-reinforcing cycle: water stress can be intensified by an increase in electricity production,(4−6) and at the same time, water scarcity can hamper the secure and sustainable supply of energy.(7,8)
Among different sources of energy, thermoelectric power is of central importance in this regard. Thermoelectric power generation constitutes 75% of the world’s net electricity generation(9) and has been the largest source of water withdrawal (86%) in the energy sector.(10) In recent years, a growing number of studies have investigated the relationship between thermal power generation and water scarcity in different countries and regions, including the United States,(11,12) the United Kingdom,(13) Middle East and North Africa,(14) South Africa,(15) and developing countries in Asia.(16)

Particular attention has been paid to China, where the thermal power industry has grown rapidly and water scarcity is a significant environmental challenge.(17−19) Existing studies have investigated various aspects of the electricity-water nexus in China, such as estimating aggregate water use by thermal power generation based on top-down data and methodologies (e.g., refs (20and21)); compiling spatial explicit water use inventories and water stress maps through bottom-up data at the power plant or generating unit-level (e.g., refs (22−25)); accounting for virtual water transfers via inter-regional or interprovincial electricity transmission (e.g., refs (26−29)); and projecting future trajectories of water use by using scenario analysis tools or energy system modeling (e.g., refs (30−32)). These analyses have revealed numerous spatial and temporal characteristics of the electricity-water nexus in China. Of note are the impacts in the water sector due to technological changes and policy interventions in the power sector. For example, historical analysis that is based on a detailed unit-level water use inventory conducted by ref (23) shows that thermal power generation in catchments under high water stress (with a water withdrawal-to-availability ratio greater than 0.4) has grown by a factor of 4.5 from 2000 to 2015 (from 643 TWh in 2000 to 2,885 TWh in 2015). At the same time, significant policy-induced technological changes, especially those in cooling technology structures, have successfully decoupled thermoelectric freshwater withdrawal from growing power generation.

Thermal power generation, especially coal-fired power, also plays a major role in India’s electricity mix. Driven by a growing population and economic development, India’s generation capacity is being rapidly expanded. Projections estimate that energy demand in India will increase by 1005 Mtoe from 2016 to 2040, more than any other country during the same period.(33) India is also projected to have the largest population increase worldwide, and will surpass China as the world’s most populous country in 2027...(34)

The paper notes that water scarcity is a huge problem in India as well as in China, and in fact, pretty much everywhere in the world. The failure to make even a weak stab at addressing climate change - all of our fantasies about electric cars, vast wind industrial parks in former wildernesses, and electric generating glass coated with millions of tons of mined, carbon reduced, and often toxic elements of the periodic table have done nothing at all except generate more fantasies - will make this worse.

The story can be told in graphics and tables from the paper:

The caption:

Figure 1. Spatial Distribution of Thermal Power Plants and Baseline Water Stress at Catchment Level. State boundaries are illustrated by light blue lines. Abbreviations of state name: AP, Andhra Pradesh; AR, Arunachal Pradesh; AS, Assam; BR, Bihar; CT, Chhattisgarh; GA, Goa; GJ, Gujarat; HR, Haryana; HP, Himachal Pradesh; JK, Jammu and Kashmir; JH, Jharkhand; KA, Karnataka; KL, Kerala; MP, Madhya Pradesh; MH, Maharashtra; MN, Manipur; ML, Meghalaya; MZ, Mizoram; NL, Nagaland; OR, Odisha; PB, Punjab; RJ, Rajasthan; TN, Tamil Nadu; TR, Tripura; UP, Uttar Pradesh; UT, Uttaranchal; WB, West Bengal. The base map is obtained from WRI’s Aqueduct Water Risk Atlas which is drawn according to defacto status and shows actual control situation. Disputed territories are supplemented and illustrated with shade.

The caption:

Figure 2. Electricity generation and freshwater withdrawal classified by baseline water stress categories.

The caption:

Figure 3. Relative Changes of Power Generation and Water Use. The base year level in 2009 is assigned as 1.0.

The caption:

Figure 4. Thermoelectric Freshwater Withdrawal (a) and Consumption (b) by the top 10 States in 2009, 2018, and 2027

The caption:

Figure 5. Spatial distribution of freshwater withdrawal, freshwater consumption, and thermoelectric water stress in 2018, and changes during the period of 2009–2018 and 2018–2027. The base map is obtained from WRI’s Aqueduct Water Risk Atlas which is drawn according to defacto status and shows actual control situation. Disputed territories are supplemented and illustrated with shade.

Some tables from the text:

Some additional text, which is involved with something called "reality:"

India’s thermal power sector has rapidly expanded in the past decade (2009–2018) with total generation capacity, including coal-fired, natural gas-fired, and nuclear power, increasing by 130% (from 101 GW in 2009 to 232 GW in 2018). This expansion was mainly driven by the commissioning of new coal-fired power plants, whose share in the total power capacity increased from 79% (80 GW) in 2009 to 86% (201 GW) in 2018. Natural gas-fired and nuclear power capacity accounted for the other 11% and 3% in 2018, respectively.

Net electricity generation increased by around 80% from 615 TWh in 2009 to 1106 TWh in 2018. The role of coal-fired power generation grew during the past decade, and it contributed to 92% (1017 TWh) of total thermal power generation in 2018, compared to 83% (615 TWh) in 2009. The lack of natural gas resources in India has impeded the development of natural gas-fired power generation. Although the installed capacity of natural gas-fired power plants rose during the study period, electricity generation decreased 43% from 88 TWh to 50 TWh. Nuclear power contributed to around 3.5% of overall generation.

It is often represented in our modern fantasies that "coal is dead" coupled with the stupid remark that the reason "coal is dead" is because of so called "renewable energy." It is telling however, and a dose of reality in the face a delusion every bit as serious - in some ways worse - that Covid is a "hoax," that coal is not dead where there is no ready access to dangerous natural gas, the use of which will scar the planet's atmosphere, water and land for eternity, all for short term comfort. This fact is highlighted in text I have bolded in this text just above. So called "renewable energy" did not save the world, is not saving the world, and will not save the world. It is a trivial form of energy, completely dependent on access and use of dangerous natural gas, and all the denial in the world will not change this fact.

Facts matter.

Nevertheless, there is discussion in the text of solutions with an eye of chasing the chimera that so called "renewable energy" is sustainable, even though one of the features of escaping poverty - poverty being an issue in India - is the abandonment of trying to survive on so called "renewable energy." This de facto discussion is here:

SWITCH is a long-term capacity expansion planning model which minimizes the cost of power system expansion and operations subject to reliability, operational, and resource availability constraints. It also helps model large, real-world power systems with high temporal and spatial resolutions relatively quickly. This is useful because including renewable energy assets in power systems requires an accurate representation of grid operations, through high temporal and special resolutions.

Whatever. The italics are mine.

India has huge thorium resources, and it has now supplanted Canada in the use of CANDU type heavy water nuclear reactors. It has also piloted a plant for the extraction of uranium from seawater.

Ironically enough - I've discussed this topic many times elsewhere - the solution to water demands for power plant cooling is ironically enough, to raise the internal temperatures so as to drive heat networks that extract additional work (exergy) from that heat, i.e. raise the efficiency of the plants to unprecedented methods. One possible inclusion in a heat network are systems that desalinate sea water. Desalination is not a panacea, and many environmental issues need to be addressed to employ it, but I believe they can be addressed by an educated, dedicated and respectful version of humanity, one not here immediately, but one that is certainly possible.

We are at a cross roads.

The functional "renewables will save us," anti-nuke guru who resides in a super energy efficient aerie on a mountain in the wealthy enclave of Snowmass, Colorado - which is represented in congress by Lorena Bobbitt, delusional gun nut Trump humper - is Amory Lovins. Amory Lovins will tell you that the goal of energy efficiency is to reduce the use of energy. Of course, Amory Lovins couldn't care less about poor people.

Maybe delusion is contagious in Snowmass.

I am disinterested in delusional bourgeois brats. Unlike the guru in Snowmass I am familiar with Jevon's paradox, well known and often observed since the 19th century, which states that increases in energy efficiency increase the use of energy. I'm fine with that because I believe that sustainable energy is possible. For me increases in efficiency are all about making energy available to the billions of people who lack it, a significant portion of whom live in India.

Have a nice weekend.

Global groundwater wells at risk of running dry

The paper I'll discuss in this post is this one: Global groundwater wells at risk of running dry (BY Scott Jasechko and Debra Perrone Science 372, 418–421 (2021) 23 April 2021)

A news item referring to the paper in the same issue of Science which is likely to be open sourced is here: The hidden crisis beneath our feet (James S. Famiglietti1,2, Grant Ferguson, Science 23 Apr 2021: Vol. 372, Issue 6540, pp. 344-345)

If memory serves me well, I have referred a number of times to a lecture I attended by Dr. Robert Kopp of Rutgers University, this one: Science on Saturday: Managing Coastal Risk in an Age of Sea-level Rise, wherein, in answer to a question from the audience (mine), Dr. Kopp explained that about 10% of sea level rise can be attributed to water pumped out of the ground and allowed to evaporate. Most of this water is used for agriculture, but it is also used in cities and in homes. I am guilty here. The water in my home is well water, which as I happen to know, contains some interesting and unpleasant substances.

This suggests - I've been musing about this a lot lately - that one path to addressing climate change would be restoring shorelines would include refilling the aquifers we've drained in the last 50 years or so in yet another expression of our accelerating contempt for all future generations, along with dried up lakes like Owens Lake in California, and dying bodies of water like Lake Baikal, the Aral Sea, the Caspian Sea, etc...

My most recent episode of such musings out loud is here: Ion-capture electrodialysis using multifunctional adsorptive membranes, which is preceded by a long dull digression on reactor physics and the mercury content of the oceans.

To anyone who argues that refilling ground water by desalination of ocean water, refilling dead lakes, dead seas etc. is geoengineering, let me say this.

There is a television show on the Science channel called Engineering Catastrophes which I watch from time to time to give me ammunition to make fun of my son the engineer. It's all about failures of bridges, buildings, roadways, etc. from things like hydrogen embrittlement, improper analysis of stresses, poor materials etc. However everything on this show is small potatoes compared to the biggest engineering catastrophe, the existing haphazard, uncontrolled and unplanned geoengineering of the entire planet, most of which has been a catastrophe of the last one hundred years.

This is not really a water problem; it is an energy problem. No, wind turbines in lobster fisheries off the coast of Maine, nor any other wind schemes designed to industrialize wilderness, will not produce even a fraction of the energy required owing to thermodynamic, mass intensity, reliability and lifetime considerations. The sooner we lose our affection for this nonsense, the more hope we will have.

The goal of geoengineering should be to restore, and nothing more.

Anyway future generations are in a world of hurt according to this paper. From the paper's introduction:

Groundwater provides nearly half of the water used for irrigated agriculture and supplies drinking water for billions of people (1, 2). Its perennial and distributed nature makes groundwater suitable for providing reliable access to potable water and supporting efforts to adapt to climate change (3). Nevertheless, access to groundwater to meet water demands may be hindered when groundwater levels decline. Groundwater levels are declining in many aquifers around the globe [e.g., (4–6)], causing groundwater wells (7) to run dry (8–10) and leaving farmers unable to irrigate and households without access to reliable and convenient drinking water.

When groundwater wells run dry, one common adaptation strategy is to construct deeper wells (11). Deeper wells tend to be less vulnerable than shallower wells to climate variability (12) and groundwater level declines (13), but even relatively deep wells are not immune to long-term reductions in groundwater storage. Despite the role of wells as a basic infrastructure used to access groundwater, information about the locations and depths of wells has never before been compiled and analyzed at the global scale. Analyzing groundwater resources at the global scale is becoming increasingly important because of groundwater’s role in virtual water trade, international policy, and sustainable development (14, 15). Nevertheless, we emphasize that groundwater is a local resource influenced by hydrogeologic conditions, water policies, sociocultural preferences, and economic drivers.

Here, we compiled ~39 million records of groundwater well locations, depths, purposes, and construction dates (supplementary materials section S1), which provide local information at the global scale. These observations promote a better understanding of spatiotemporal patterns of well locations and depths (16, 17). Groundwater data are notoriously difficult to collect and collate (18, 19). The ~39 million wells are situated in 40 countries or territories that represent ~40% of global ice-free lands (average data density of 0.7 wells/km2; Fig. 1). Half of all global groundwater pumping takes place within our study countries or territories [fig. S2, reference (2), and supplementary materials section S5.1], which are home to >3 billion people (table S1).

Fig. 1 Groundwater well depths in countries around the globe.

The caption:

The dataset contains ~39 million wells in 40 countries or territories (see inset map). Blue points mark shallower wells and red points mark deeper wells in Canada, the United States (white areas mark states where data are unavailable), and Mexico (A); Argentina (partial coverage), Bolivia (partial coverage), Brazil, Chile, and Uruguay (B); Iceland, Portugal, Spain, France, Germany (partial coverage), Denmark, Sweden, Norway, Italy, Slovakia, Slovenia, Belgium, Poland, Latvia, Estonia, Czech Republic, Hungary, United Kingdom, and Ireland (C); Namibia and South Africa (D); Thailand and Cambodia (E); and Australia (F). National-level analyses are available in figs. S37 to S435.

Fig. 2 Fraction of areas with deeper well drilling versus shallower well drilling for five time periods among study countries.

The caption:

Well-deepening trends are more common than well-shallowing trends for the majority of time periods for the majority of countries (national-level analyses in figs. S37 to S435). (A) The fraction of 100 km by 100 km study areas where wells are being drilled deeper over time (Spearman ρ > 0; regression of well completion depth versus well construction date). Each diamond represents well construction depth variations over time for a given country (e.g., blue diamonds are regressions for years 2000–2015; see legend above figure); some points overlap. (B to L) Spearman ρ determined by regression of well depth versus construction date for the time interval 2000–2015 in 11 countries [i.e., the fraction of all 100 km by 100 km areas in these maps with Spearman ρ > 0 correspond to the blue diamonds in (A)]. Blue shades mark 100 km by 100 km areas where wells are being constructed shallower over time (i.e., Spearman ρ < −0.1); orange and red shades mark 100 km by 100 km areas where wells are being constructed deeper over time (i.e., Spearman ρ > 0.1.)

Fig. 3 Well construction depth trends at locations close to ( 0) significantly (Spearman P < 0.05) over time.

The caption:

Results derive disproportionately from Australia, Canada, France, Mexico, New Zealand, Sweden, and the United States (tables S64 to S69). The histograms are distributions of Spearman rank coefficients as determined through regression analyses of well completion depths versus well completion dates at sites close to a monitoring well where water levels have declined significantly over time (Spearman ρ > 0 and Spearman P < 0.05 determined through regression analyses of measured depth to water in monitoring well versus water level measurement date). Each plot in (A) to (E) represents one study time interval [e.g., (A) presents results for 1950–1975]. Although all distributions skew right (i.e., well deepening where groundwater levels are declining), a substantial number of sites indicate that newer wells are not being constructed substantially deeper than older wells where groundwater levels are declining. Curly brackets above each plot in (A) to (E) provide the percentage of well construction depth trends falling within the following Spearman ρ ranges: −1.0 to −0.2, −0.2 to 0.2, and 0.2 to 1.0.

An excerpt of the conclusion of this short paper:

From India to the United States, wells are already running dry because of groundwater level declines (22, 26, 34, 35). When a well runs dry, there are a number of ways to adapt: (i) construct a new and deeper well or deepen the existing well that ran dry (10, 13); (ii) access alternative water sources (10, 29); (iii) conserve water through behavioral changes or technological adoptions [e.g., switching to crops that are less water intensive; adopting irrigation approaches that reduce water losses (25)]; (iv) sell the property (10); or (v) abandon activities that require high water inputs, such as irrigation (35). In Karnataka, India, some households that have had their well run dry have offset lost agricultural profits by seeking off-farm income (35). The transition away from agriculture can have longer-term impacts on the household, such as debt accrual while seeking alternative employment and lost educational opportunities for children who join the workforce early to supplement household income (35). In California’s Central Valley (United States) and several other agricultural hubs around the globe, typical agricultural wells are deeper than domestic wells (supplementary materials sections S5.5 to S5.6); as a result, rural domestic wells are running dry disproportionately relative to agricultural wells...

...Groundwater wells supply water to billions of people around the globe (2, 13, 14, 36). Groundwater depletion is projected to continue in some areas where it is already occurring, and even expand to new areas not yet experiencing depletion (37)...

...Our work highlights the vulnerability of existing wells to groundwater depletion because (i) many wells are not much deeper than the local water table, making them likely to run dry with even modest groundwater level declines (supplementary materials section S6), and (ii) deeper well construction is common but not ubiquitous where groundwater levels are declining...

History will not forgive us, nor should it.

Have a nice weekend.

A day in the life.

The rate of denovo genetic mutations in the children of parents exposed to Chernobyl radiation.

The paper I'll discuss in this post is this one: Lack of transgenerational effects of ionizing radiation exposure from the Chernobyl accident M. Yeager et al., Science 10.1126/science.abg2365 (2021).

This week marks the 34th anniversary of the steam explosion at the Chernobyl Nuclear Power Plant. The graphite moderator in plant burned for weeks and much of the inventory of volatile fission products was released into the environment, and detected in easily measurable amounts all across Europe, as far away as Scotland.

This event garnered huge attention at the time and still garners significant attention.

It is reported that about six to seven million people die each year from air pollution, meaning that about 200-250 million people have died from air pollution since the explosion of the nuclear reactor, proving in the minds of many that nuclear power is "too dangerous," while apparently the combustive use of fossil fuels and biomass, responsible for these 200-250 million deaths, is not "too dangerous." Neither is climate change "too dangerous." These facts, deaths from air pollution, and the acceleration of climate change despite endless talk about and expenditures on so called "renewable energy," unlike Chernobyl do not garner huge attention.

Go figure.

From the introduction to the paper:

Nearly all inherited genetic variation is present in the germline DNA of at least one parent; however, a small number of transmitted variants are unique, having arisen due to random mutations in gametes (sperm and oocytes), and are known as de novo mutations (DNMs). DNMs are critical building blocks of evolution and the only class of genomic variation that has not undergone extensive evolutionary purifying selection (purging of highly deleterious but non-lethal variants), making DNMs a unique form of inherited variation different from the genetic variation investigated in mapping complex traits and diseases (1). DNMs have been of intense interest because of their role in human disease, particularly neurodevelopmental disorders (2, 3).

Only recently has it been feasible to comprehensively investigate DNMs genome-wide at the population level in humans by whole-genome sequencing (WGS) of mother/father/child trios. Recent reports of human DNMs characterized by WGS of trios estimate between 50 and 100 new mutations arise per individual per generation (2, 4–8), consistent with the population genetic estimate that the human mutation rate for single-nucleotide variants (SNVs) is approximately 1×10−8 per site per generation (9, 10). The strongest predictor of DNMs per individual is paternal age at conception (2–6, 8) with an increase of 0.64-1.51 per one-year increase in paternal age (6, 8, 11) while a maternal effect of approximately 0.35 per one-year increase in age was observed (6, 8, 12). Transgenerational studies of radiation exposure have primarily focused on disease (cancer, reproductive, and developmental) outcomes and have reported inconclusive results (13, 14).

Exposure to ionizing radiation is known to increase DNA mutagenesis above background rates (15, 16). Animal and cellular studies suggest high doses of ionizing radiation can lead to DNMs in offspring, particularly through double-stranded breaks (13, 17). Human studies have sought a biomarker of prior radiation injury (13, 18, 19), but have examined a small number of minisatellites and microsatellites, yielding inconclusive results (20–23). A WGS study of three trios from survivors of the atomic bomb in Nagasaki did not reveal a high load of DNMs (20), while a single-nucleotide polymorphism (SNP) array study of 12 families exposed to low doses of Caesium-137 from the Goiania accident in Brazil reported an increase in large de novo copy-number variants (24). No large comprehensive effort has explored DNMs genome-wide in children born from parents exposed to moderately high amounts of ionizing radiation yet possible genetic effects have remained a concern for radiation-exposed populations, such as the Fukushima evacuees (25).

Herein, we examine whether rates of germline DNMs were elevated in children born to parents exposed to ionizing radiation from the 1986 Chernobyl (Chornobyl in Ukrainian) disaster, where levels of exposure have been rigorously reconstructed and well-documented (26). Our study focused on children born of enlisted cleanup workers (“liquidators”) and evacuees from the town of Pripyat or other settlements within the 70-km zone around Chernobyl Nuclear Power Plant in Ukraine (27) after the meltdown, some of whom had extremely high levels of radiation exposure and several of whom experienced acute radiation syndrome. We performed Illumina paired-end WGS (average coverage 80X), SNP microarray analysis, and relative telomere length assessment on available samples from 130 children from 105 mother-father pairs. The parents had varying combinations of elevated gonadal ionizing radiation exposure from the accident (tables S1 to S3), and included a combination of exposed fathers, exposed mothers, both parents exposed and neither parent exposed (27)...

Some figures from the paper:

The caption:

Fig. 1 Detected DNMs per genome based on distributions of parental age at conception.
Analyses are presented by increasing paternal and maternal age at conception, paternal and maternal dose, birth year of child, and paternal and maternal smoking at conception. All plots are univariate and do not account for other potentially correlated variables (for example, maternal age does not account for high correlation with paternal age).

The caption:

Fig. 2 Distribution of de novo SNVs by type of nucleotide change across six studies.
n = number of children sequenced (adapted from (39)). Liftover was used to convert coordinates to hg38 for all studies and the reference for CpG sites were defined with respect to that reference sequence. Only autosomes were included. Error bars show binomial 95% confidence intervals. Studies included Kong (2); Wong (8); Francioli (4); Michaelson (3); Jónsson (6); and Chernobyl (present study).

Some additional text:

Although it is reassuring that no transgenerational effects of ionizing radiation were observed in adult children of Chernobyl cleanup workers and evacuees in the current study, additional investigation is needed to address the effects of acute high-dose parental gonadal exposure closer to conception. The upper 95% confidence bound suggests the largest effect consistent with our data is less than 1 DNM per 100 mGy from paternal or maternal exposure (Table 3 and tables S8 and S9). Previously, Dubrova et al. (22, 29) reported a two-fold increase in mini-satellite mutations in children born to parents living in a highly exposed region of Belarus. Weinberg et al. (34) reported an increase in the mutation rate at microsatellite loci among children born to cleanup workers. Subsequent small studies have not reported an increased mini-satellite or microsatellite mutation rate in children of cleanup workers, including those with low doses (0.09-0.23 Gy) (21, 30, 35) or in children of the atomic-bomb survivors of Hiroshima or Nagasaki (31).

Our study evaluated peripheral blood from adult children conceived months or years after the Chernobyl accident, which limited the ability to assess exposure closer to conception; however, there was no evidence of notable differences in DNMs in children born the following year (1987). Since these families were recruited several decades after the accident, we acknowledge potential survivor bias among sampled children, although this is unlikely since there is no consistent demonstration in humans of sustained clinical effects of preconception ionizing radiation exposure (36)...

....Although it is reassuring that no transgenerational effects of ionizing radiation were observed in adult children of Chernobyl cleanup workers and evacuees in the current study, additional investigation is needed to address the effects of acute high-dose parental gonadal exposure closer to conception. The upper 95% confidence bound suggests the largest effect consistent with our data is 1 Gy), but lower maternal dose was not associated with elevated DNMs, consistent with animal studies (13). Furthermore, our analysis of 130 adult children from 105 couples using 80X coverage of short-read technology suggests that if such effects on human germline DNA occur, they are uncommon or of small magnitude. This is one of the first studies to systematically evaluate alterations in human mutation rates in response to a man-made disaster, such as accidental radiation exposure. Investigation of trios drawn from survivors of the Hiroshima atomic bomb could shed further light on this public health question

For the record, I am an older father, and therefore there is a higher probability that my sons have DNM's than there may be to the children of men who were younger than I was before coming a father. If so these were happy mutations, since my sons are better men than I was at their age. I love my mutant boys.

Have a nice day tomorrow.

A daughter decides to do an impression of her mom working from home in the age of Covid.

Sign up for a lecture by Amartya Sen, "Attacks on Democracy: Challenges and Solution" at eCornell.

eCornell: ATTACKS ON DEMOCRACY Challenges and Solutions With Amartya Sen

Brief Excerpts from the Wikipedia page about him:

Amartya Kumar Sen CH (Bengali: [ˈɔmortːo ˈʃen]; born 3 November 1933) is an Indian economist and philosopher, who since 1972 has taught and worked in the United Kingdom and the United States. Sen has made contributions to welfare economics, social choice theory, economic and social justice, economic theories of famines, decision theory, development economics, public health, and measures of well-being of countries.

He is currently a Thomas W. Lamont University Professor, and Professor of Economics and Philosophy at Harvard University.[4] He formerly served as Master of Trinity College at the University of Cambridge.[5] He was awarded the Nobel Memorial Prize in Economic Sciences[6] in 1998 and India's Bharat Ratna in 1999 for his work in welfare economics. The German Publishers and Booksellers Association awarded him the 2020 Peace Prize of the German Book Trade for his pioneering scholarship addressing issues of global justice and combating social inequality in education and healthcare...

...Sen's interest in famine stemmed from personal experience. As a nine-year-old boy, he witnessed the Bengal famine of 1943, in which three million people perished. This staggering loss of life was unnecessary, Sen later concluded. He presents data that there was an adequate food supply in Bengal at the time, but particular groups of people including rural landless labourers and urban service providers like barbers did not have the means to buy food as its price rose rapidly...

...On one morning, a Muslim daily labourer named Kader Mia stumbled through the rear gate of Sen's family home, bleeding from a knife wound in his back. Because of his extreme poverty, he had come to Sen's primarily Hindu neighbourhood searching for work; his choices were the starvation of his family or the risk of death in coming to the neighbourhood. The price of Kader Mia's economic unfreedom was his death. Kader Mia need not have come to a hostile area in search of income in those troubled times if his family could have managed without it. This experience led Sen to begin thinking about economic unfreedom from a young age.

In Development as Freedom, Sen outlines five specific types of freedoms: political freedoms, economic facilities, social opportunities, transparency guarantees, and protective security...

These eCornell lectures are quite wonderful. The last one I attended featured a conversation with Bill Clinton on exactly this subject, saving democracy...

I don't plan to miss this one.

Go ahead, I dare you, ask for time on Badger and Grizzly...

I'm not sure that this is acceptable on a family blog, but here goes:

I came across this text today:

Therefore, we propose a total one-year allocation of 5,050,000 CPU-hrs on Badger and Grizzly:
25,000 for (1) + 25,000 for (2) + 5,000,000 for (3). This should be divided into 50,000 CPU-hrs on Badger
for (1) and (2) and 5,000,000 CPU-hrs on Grizzly for (3). Total data storage needs are 10 TB in Lustre
scratch space and Campaign Storage space. Many of the large trajectory files may be deleted after
publication of the resulting paper; hence, we do not need as much archival storage space. We ask for 5 TB
Archival Space.

It's from here:

Salts in Hot Water: Developing a Scientific Basis for Supercritical Desalination and Strategic Metal Recovery

Badger and Grizzly indeed...

In the battle against senility, I've managed to smoothly and correctly spell "pyrolysis."

I don't know why, but for the last several years, whenever I go to spell the word "pyrolysis," I find myself typing pyrrolysis, pyrollysis, pyrrollysis, etc.

I've noticed that in the last several months, I'm spelling the word correctly every time.

When I was a kid, I thought I was a candidate for spelling bee competitions. The invention of the computer disabused me of that notion, but now, near the end of my life, I've managed to correctly spell, every time, this word, which I run across several times a week, sometimes, like today, ten or twelve times in a single day.
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