HN user

frowin

60 karma

flipper@frowin.me

Posts0
Comments20
View on HN
No posts found.

Hyperpolarization also allows for cheaper MRI scanners. With hyperpolarization, you achieve polarization (needed for SNR) without the need of big magnets (=expensive). Even in rich countries, MRI scanners reach their physical and technical limits. 3T magnets are already 7-figures and costs of bigger magnets will increase non-linearly. Moreover, with higher fields, side effects increase, too.

Great explanation. Indeed, the "rotation/tumbling" is nothing to worry about. One of our biggest challenges is relaxation. The moment we polarize, the clock ticks. Usually, the time scope is around 15-90s. I'm in the field of para-hydrogen and built automated systems which carry out the chemical reactions, polarization transfers and sample cleaning. Many hyperpolarization experiments with para-hydrogen prefer nasty solvents as chloroform or methanol. It is a technical challenge to replace them by water within seconds. One of my favorite topics is Xenon hyperpolarization. It's very elegant, no cleaning required, no wet chemistry, and provides amazing lung scans.

I'm finishing my PhD in hyperpolarization (hopefully) soon. In my opinion, hyperpolarization will significantly contribute to early-stage diagnosis. We're designing machines, processes, and chemicals that create novel contrast agents for MRI, enabling the localization of cancer cells and even tracking their metabolism. For example, it's possible to inject hyperpolarized pyruvate and track its conversion to lactate. Essentially, this technique boosts the MRI/NMR signal of the contrast agent by up to 100,000-fold. When the contrast agent undergoes metabolism, it creates a unique signal footprint through chemical shift changes, which can aid in characterizing cancer.

As a scientist, I'm so glad that we're forced to publish all our primary/secondary data along with the publication itself. It's stored in a repository which is "locked" when the DOI (digital object identifier) is generated. Overall, the publishing process is tedious and frustrating, but this extra work is crucial and cases like this makes that very clear. However, in most of the recent cases you didn't even need to look at the data as even the publication itself shows the misconduct.

I think not. It keeps battery cycles low and is likely better than some other behavior. As far as I remember, batteries don't like to go way below 20% and don't like fast charging from 80% upwards. However, to my knowledge, it is wise to drain the battery 1-2 times a year so that the charging controller can calibrate. A way to do that is to type "yes" in your terminal (or 3-4 terminals) and wait, it will make the CPU run at 100%. After your MacBook shut off, leave it for some hours before you charge it again.

It's not only a matter of aesthetics but bacteria etc. Your brush head collects a sh*tload of food waste (which you don't see with your eyes) and remains a bit wet after usage. Perfect substrate for some living organisms. If you have a microscope, feel free to have a closer look.

Clearly, he possesses considerable expertise, but it's puzzling why such a skilled individual would falter towards the end, resulting in poor solder joints on the 2.54mm pin headers. This isn't merely a question of aesthetics; these joints are susceptible to failure.

His work is commendable, but I would encourage him to either learn proper soldering techniques or, if he already possesses the skills, to take a moment to use some flux and clean up the joints. It's a simple process that takes just three seconds per joint.

A friend wanted to register at facebook and his last name is "couple" in our language. Facebook shows an error claiming, that couples are not allowed to share an account - they should open separate accounts. So far so good. However, Facebook continued to refuse opening his account, even when he sent his id card. Now his last name are the two first letters of his last name which seems to be no violation :)

I think in the legend,

2021 should be 2027 and 2017 should be 2021.

Otherwise I doesn't make sense to me. Maybe someone wrote by accident 2017 instead of 2027 and then swapped the legend so that it fits the graph's message.

Still, wondering why 6 co-authors, one editor and several peer-reviewers didn't notice it.

Or am I getting the graph wrong?

It fascinates me, that volume and automation can make this profitable. Very nice article and I would love to see a cost breakdown of a PCB manufacturer. There is still labour involved in manual handling and even communication with customers.