Recent comments in /f/science

GeoGeoGeoGeo OP t1_jdbv2df wrote

Reply to comment by Jeffersness in Findings show substantial amounts of H₂O could only have been delivered to Earth by means of unmelted material, such as chondrites, and not melted material such as achondrites. The results could have important implications for the search for water—and life—on other planets by GeoGeoGeoGeo

Deuterium to hydrogen ratios relative to Earth's Standard Mean Ocean Water (SMOW) values for Ring B, and Titan are relatively close though Enceladus and Phoebe greatly differ. Still, CI chondrite D/H ratios are closer to Earth's than any of Saturn's rings or moons.

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GeoGeoGeoGeo OP t1_jdbufn3 wrote

Reply to comment by jmysl in Findings show substantial amounts of H₂O could only have been delivered to Earth by means of unmelted material, such as chondrites, and not melted material such as achondrites. The results could have important implications for the search for water—and life—on other planets by GeoGeoGeoGeo

Essentially achondrites are melted materials, all produced by melting of their parent bodies such as differentiated planetesimals and differentiated planetary bodies, like the Moon or Mars. Chondrites, on the other hand, have experienced no significant melting as they are pre-planetary rocks, or the building blocks of planets. The implication of this paper then is that Theia (the giant impactor hypothesis that leads to the formation of the moon) could not have delivered water to the early Earth.

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jmysl t1_jdbtpch wrote

Reply to Findings show substantial amounts of H₂O could only have been delivered to Earth by means of unmelted material, such as chondrites, and not melted material such as achondrites. The results could have important implications for the search for water—and life—on other planets by GeoGeoGeoGeo

I was trying to figure out the difference between, “unmelted” and “not melted.” At first it looked like a typo.

For clarity, the water appears to come from unmelted materials and not from melted materials.

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sonoma95436 t1_jdbs052 wrote

Reply to Canada scientists create new method to break down toxic ‘forever chemicals’ | University of British Columbia researchers develop silica-based material with ability to absorb wider range of harmful chemicals by Hrmbee

While I applaud the use of new substances to absorb and filter out forever chemicals, they do not break them down. They remain for disposal. It's a very good step but not the same as biodegradable.We must keep up the fight to get companies to stop using them in the first place.

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SaltZookeepergame691 t1_jdbrkvk wrote

Reply to comment by SuppaCoup in Phase 1 study: New medicine extends terminally-ill cancer patients' lives. Seventy percent of the patients who tested the medicine were stable after six weeks. Twelve continued the medication and were stable for 18 weeks. One woman took the medication for 17 months, and was stable for over two years by Wagamaga

Not an oncologist, but it’s far too early to tell. They saw no tumour responses, and the length of response in a couple of patients could easily just be chance.

They are now running a (single arm) trial in patients with platinum sensitive ovarian cancer in conjunction with platinum chemotherapy, so they clearly see this as an adjunctive therapy. But as said elsewhere, there is a huge way to go from phase 1 to rolling out an actually effective drug that provides net benefits to patients.

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FrozenToonies t1_jdbqtkv wrote

Reply to Canada scientists create new method to break down toxic ‘forever chemicals’ | University of British Columbia researchers develop silica-based material with ability to absorb wider range of harmful chemicals by Hrmbee

Whatever this tech entails, it needs to be integrated into existing facilities. There’s no land available for a new facility in the lower mainland in BC. A new proposed environmental plant was just recently denied because the only land was a nature preserve.

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SuperNovaEmber t1_jdblu3n wrote

Reply to comment by born2bfi in Air pollutants have been confirmed to increase the risk of Alzheimer's dementia. Air pollutants enter the lungs through the respiratory tract and cause inflammation, which causes various diseases throughout the body, especially the inflammation of nerves when it reaches the brain. by Wagamaga

It's fun to think about how many prophets likely had severe mental illnesses like schizophrenia.

Sadly, religion starts making a little too much sense once you factor in the collective delusions of the mentally ill.

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Hrmbee OP t1_jdbl6r4 wrote

Reply to Canada scientists create new method to break down toxic ‘forever chemicals’ | University of British Columbia researchers develop silica-based material with ability to absorb wider range of harmful chemicals by Hrmbee

A link to the original research below:

Electrochemical degradation of PFOA and its common alternatives: Assessment of key parameters, roles of active species, and transformation pathway

Abstract:

>This study investigates an electrochemical approach for the treatment of water polluted with per- and poly-fluoroalkyl substances (PFAS), looking at the impact of different variables, contributions from generated radicals, and degradability of different structures of PFAS. Results obtained from a central composite design (CCD) showed the importance of mass transfer, related to the stirring speed, and the amount of charge passed through the electrodes, related to the current density on decomposition rate of PFOA. The CCD informed optimized operating conditions which we then used to study the impact of solution conditions. Acidic condition, high temperature, and low initial concentration of PFOA accelerated the degradation kinetic, while DO had a negligible effect. The impact of electrolyte concentration depended on the initial concentration of PFOA. At low initial PFOA dosage (0.2 mg L−1), the rate constant increased considerably from 0.079 ± 0.001 to 0.259 ± 0.019 min−1 when sulfate increased from 0.1% to 10%, likely due to the production of SO4•–. However, at higher initial PFOA dosage (20 mg L−1), the rate constant decreased slightly from 0.019 ± 0.001 to 0.015 ± 0.000 min−1, possibly due to the occupation of active anode sites by excess amount of sulfate. SO4•– and •OH played important roles in decomposition and defluorination of PFOA, respectively. PFOA oxidation was initiated by one electron transfer to the anode or SO4•–, undergoing Kolbe decarboxylation where yielded perfluoroalkyl radical followed three reaction pathways with •OH, O2 and/or H2O. PFAS electrooxidation depended on the chemical structures where the decomposition rate constants (min−1) were in the order of 6:2 FTCA (0.031) > PFOA (0.019) > GenX (0.013) > PFBA (0.008). PFBA with a shorter chain length and GenX with –CF3 branching had slower decomposition than PFOA. While presence of C–H bonds makes 6:2 FTCA susceptible to the attack of •OH accelerating its decomposition kinetic. Conducting experiments in mixed solution of all studied PFAS and in natural water showed that the co-presence of PFAS and other water constituents (organic and inorganic matters) had adverse effects on PFAS decomposition efficiency.

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Reply to Findings show substantial amounts of H₂O could only have been delivered to Earth by means of unmelted material, such as chondrites, and not melted material such as achondrites. The results could have important implications for the search for water—and life—on other planets by GeoGeoGeoGeo

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Hrmbee OP t1_jdbkypv wrote

Reply to Canada scientists create new method to break down toxic ‘forever chemicals’ | University of British Columbia researchers develop silica-based material with ability to absorb wider range of harmful chemicals by Hrmbee

>Scientists at the University of British Columbia announced on Wednesday that they had developed a new silica-based material with ability to absorb a wider range of the harmful chemicals, and new tools to break them apart them. > >“This is very exciting because we can target these difficult-to-break chemical bonds – and break them for good,” said researcher Madjid Mohseni, who focuses on water quality and water treatment. > >The chemicals, also known as PFAS (per-and polyfluoroalkyl substances) are used for non-stick or stain-resistant surfaces, including clothing, cookware, stain repellents and firefighting foam. But they are also notoriously difficult to break down naturally, giving them the name “forever chemicals”. > >... > >Current technologies often use activated carbon to filter out the chemicals, but are largely only able to target what researchers call the “long-chain” versions of PFAS – those with more than six carbon bonds. Following recent bans, however, industry has shifted to creating ‘short chain’ iterations of the chemical. > >Those versions “are equally as toxic and they stay in the water better. And as a result, current technologies like activated carbon really aren’t as effective,” said Mohseni. > >Most household water filters use activated carbon – and as a result, miss a wide range of possibly harmful chemicals. > >His team also found that the current filters concentrate the absorbed chemicals, creating a “highly toxic” form of waste that consumers throw into the garbage. > >Such filters “are not addressing the problem. We’re just temporarily fixing it and letting those chemicals stay in the environment,” he said. > >To combat the deficiencies in combatting PFAS, the team has developed a new silicate absorbing material that captures a far wider range of chemicals. The thin material can also be reused repeatedly. > >To destroy the chemicals, Mohseni says researchers use either electrochemical or photochemical processes to break the carbon-fluorine bond. The team first published their findings in the journal Chemosphere.

This is some good news as far as PFASes are concerned, though ultimately we do need to limit their broader use in our manufacturing processes. Allowing manufacturers to jump from one compound to another to avoid regulation seems to be a major failing in our current regulatory systems.

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