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This study presents the first ex-vivo positronium imaging of human tissues using the modular J-PET scanner with the $^{44}$Sc radionuclide. The $^{44}$Sc isotope was produced via the $^{44}$Ca(p, n)$^{44}$Sc nuclear reaction and used to perform positronium imaging of phantom composed of human adipose tissue, cardiac myxoma tissue, thrombi blood clot, and also porous polymer XAD4, and a certified reference material (CRM) made from fused silica. The experiment demonstrates the suitability of $^{44}$Sc as a positron source for positronium imaging. The performance of J-PET for positronium imaging with $^{44}$Sc was validated by proper reconstruction of the mean orthopositronium lifetime for CRM material and XAD-4 polymer. The mean ortho-positronium (oPs) lifetimes determined for adipose tissue, cardiac myxoma tissues and thrombi were consistent with results of previous experiments. The study highlights the potential $^{44}$Sc radionuclide for positronium lifetime imaging (PLI).

Deep learning advanced to one of the most important technologies in almost all medical fields. Especially in areas, related to medical imaging it plays a big role. However, in interventional radiotherapy (brachytherapy) deep learning is still in an early phase. In this review, first, we investigated and scrutinised the role of deep learning in all processes of interventional radiotherapy and directly related fields. Additionally we summarised the most recent developments. To reproduce results of deep learning algorithms both source code and training data must be available. Therefore, a second focus of this work was on the analysis of the availability of open source, open data and open models. In our analysis, we were able to show that deep learning plays already a major role in some areas of interventional radiotherapy, but is still hardly presented in others. Nevertheless, its impact is increasing with the years, partly self-propelled but also influenced by closely related fields. Open source, data and models are growing in number but are still scarce and unevenly distributed among different research groups. The reluctance in publishing code, data and models limits reproducibility

Scientists have successfully generated electricity with a hydrogen turbine that produces its own pressure through detonation waves instead of relying on a mechanical compressor。 The breakthrough could unlock dramatically more efficient power systems for clean energy and future aviation

Hidden moon ice may reveal itself through the way it bends and reflects vibrations from moonquakes。 The technique could help astronauts locate vital water supplies and uncover clues about the origins of Earth’s oceans

Photons traveling through a cloud of atoms can emerge so early that they appear to have spent a negative amount of time inside。 Researchers tested whether this was merely a misleading feature of the light pulse by making extremely weak measurements of the atoms。 Surprisingly, the atoms confirmed the same negative dwell time

A new chemical process can transform three of the most common plastics into high-purity hydrogen without sorting them first。 The technique operates at much lower temperatures than traditional gasification and captures most of the plastic’s carbon in solid or liquid forms instead of releasing it as carbon dioxide

Phone and Bluetooth signals could turn roadside cameras into far richer tracking tools

A surprisingly simple change could make sodium-ion batteries far more powerful while opening the door to turning seawater into drinking water。 Researchers at the University of Surrey found that sodium vanadium oxide performs much better when its naturally occurring water is left inside instead of being removed during manufacturing

Silver nanocatalysts have been found to switch where they perform their most important reactions depending on whether a solid oxide cell is making electricity or hydrogen。 The discovery could enable smarter catalyst designs that boost clean power generation while making green hydrogen more energy-efficient

Trump has resisted urge to fire FCC Democrat despite recent Supreme Court win

Cassini data has revealed a surprising twist in Saturn’s magnetic shield: the planet’s rapid rotation appears to drag a key opening in its magnetosphere far toward the afternoon side instead of keeping it near noon, as happens on Earth。 The finding confirms that giant planets like Saturn operate under a fundamentally different magnetic regime, wher

A reminder of the perils of digital ownership

Recall of jalapeño products spans 26 states, major retailers, a variety of foods

A person’s sleeping brain may reveal warning signs of dementia long before memory problems begin。 Researchers used machine learning to analyze EEG recordings from about 7,000 adults and found that an older-than-expected “brain age” was tied to a sharply higher dementia risk。 Every additional 10 years of brain aging raised that risk by nearly 40%

Amazon announces first off-the-grid data center in race to reap AI profits

August brings four major celestial events, including a solar eclipse and the peak of the Perseid meteor shower。 Dark New Moon skies could make the Perseids especially impressive, while Venus will blaze in the west after sunset。 A deep partial lunar eclipse closes the month, darkening most of the Moon

Meta has been trailing competitors。 Zuckerberg thinks he's found a way forward

Scientists have identified LHAASO J1912+1014u as a cosmic accelerator that can push protons beyond one quadrillion electron volts。 The finding may help reveal where the Milky Way’s most energetic cosmic rays come from and how they influence the galaxy

A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people。 Frequent contact was linked to greater tension and mistrust, while the crew increasingly divided into cultural and language-based groups