Lifeboat Foundation

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A new report by Computer scientists from the National Institute of Standards and Technology presents new kinds of cyberattacks that can “poison” AI systems.

AI systems are being integrated into more and more aspects of our lives, from driving vehicles to helping doctors diagnose illnesses to interacting with customers as online chatbots. To perform these tasks the models are trained on vast amounts of data, which in turn helps the AI predict how to respond in a given situation.

In this study, we conducted behavioral experiments and measured survival rates in local caves to minimize the impacts of factors other than light. Although energy-costly eyes were highly reduced or lost in cave-dwelling Leptonetela spiders, which spend their entire life cycles in the complete absence of light, our results demonstrated that they could detect light, and light cues may be used to avoid the perilously dry environment outside the cave. The annotation of core PPGs based on transcriptomic data suggests that cave-dwelling Leptonetela spiders have retained a nearly complete set of PPGs as in the entrance spiders. The molecular evolutionary analysis showed strong purifying selection on PPGs of cave-dwelling Leptonetela spiders. Therefore, our study provides evidence supporting the hypothesis that the phototransduction system of cave-dwelling eyeless Leptonetela spiders may have been under purifying selection rather than being a phylogenetic relic. Our results thus refute the neutral hypothesis.

Leptonetela spiders are small cryptozoic spiders that build sheet webs for capturing prey in twilight or lightless environment, such as leaf litter, rotting logs, rock crevices, and caves (31). Light is suggested to be the primary selective force driving the evolution of eyes of cave animals, thus, eyes are often reduced or lost as cave preadaptation in many litter-dwelling arthropods (36–38). Leptonetela spiders have lost anterior median eyes that are generally involved in identifying and stalking prey in spiders, likely due to their twilight or lightless habitats. In addition, cave-dwelling Leptonetela spiders living in lightless deep caves exhibit various degrees of eye reduction (highly reduced or eyeless) compared to their entrance spider relatives that have six intact eyes. Thus, Leptonetela spiders provided an ideal system for studying the evolution of eyes and visual systems.

This study provides evidence demonstrating negative phototaxis in cave-dwelling spiders, a highly diverse group that plays a critical role in cave ecosystems as top predators (23). Negative phototaxis has frequently been found in other subterranean animals. For example, the cave-dwelling carrion beetle Ptomaphagus hirtus that has highly reduced eyes nonetheless displays strongly negative phototaxis and maintains a reduced but functional phototransduction system, as shown by transcriptomic data (13). However, Langille et al. (14) reported that five of six subterranean water beetles completely lacked phototactic responses, and the authors proposed negative phototaxis as a preadaptation to living in permanent darkness for ancestral cave-dwelling animals. We speculate that drought resistance may play an important role in the retention of PPGs in Leptonetela spiders.

The work demonstrates control over key properties leading to better performance.

MIT researchers and colleagues have demonstrated a way to precisely control the size, composition, and other properties of nanoparticles key to the reactions involved in a variety of clean energy and environmental technologies. They did so by leveraging ion irradiation, a technique in which beams of charged particles bombard a material.

They went on to show that nanoparticles created this way have superior performance over their conventionally made counterparts.

Quantum computing is becoming more accessible for performing calculations. However, research indicates that there are inherent limitations, particularly related to the quality of the clock utilized.

There are different ideas about how quantum computers could be built. But they all have one thing in common: you use a quantum physical system – for example, individual atoms – and change their state by exposing them to very specific forces for a specific time. However, this means that in order to be able to rely on the quantum computing operation delivering the correct result, you need a clock that is as precise as possible.

But here you run into problems: perfect time measurement is impossible. Every clock has two fundamental properties: a certain precision and a certain time resolution. The time resolution indicates how small the time intervals are that can be measured – i.e. how quickly the clock ticks. Precision tells you how much inaccuracy you have to expect with every single tick.

New technology interprets archaeological findings from Biblical times. The new study scientifically corroborates an event described in the Second Book of Kings – the conquest of the Philistine city of Gath by Hazael King of Aram.

The first Artemis robotic launch to the Moon … An Artemis lunar robotic rover is halfway built … And an up-close look at a volcanic moon … A few of the stories to tell you about – This Week at NASA! https://youtu.be/PIg5syFH7qg The First Commercial Robotic Launch to the Lunar Surface U.

First, we halved the deep methane abundance (model A), since we know the polar regions are methane-depleted, but found that although such a change produces changes in (I/F)₀ and k that reasonably approximate the shape of observed differences between the polar and equatorial regions in Fig. 12, the amplitude is not sufficiently large and is close to zero at blue wavelengths. Secondly, we tried halving the methane abundance and increasing the opacity of the Aerosol-2 layer, τ₂, by 1.0 (model B), from 4.6 to 5.6. Note that all opacities quoted here are at a reference wavelength of 800 nm. Here, we see an increase in the (I/F)₀ and k difference at green wavelengths, but a decrease at blue wavelengths. The reason for this is that the Aerosol-2 particles are retrieved to have increased imaginary refractive index at blue wavelengths (Irwin et al. 2022), which lowers the single-scattering albedo here. Hence, increasing the Aerosol-2 opacity reduces the reflectivity at blue wavelengths, rather than increasing it. How then can we match the observed differences between the polar and equatorial spectra of the 2002 HST/STIS data? In the study of James et al. (2023), noted earlier, it was found that the optimal solution was to not only increase the opacity of the particles in the Aerosol-2 layer, but also make them more reflective at wavelengths longer than 500 nm. We could have similarly adjusted the imaginary refractive index spectra, n_imag, of the Aerosol-2 particles (lower n_imag values increase the single-scattering albedo), but in a parallel analysis of VLT/MUSE observations of Neptune, Irwin et al. (2023b) found that the observed spectra of deep bright spots could be well approximated by adding a component of bright particles to the existing Aerosol-1 layer at ∼5 bar. We wondered whether a similar approach might be applicable here. Changes in the Aerosol-1 layer cannot account for the observed HST/STIS pole–equator differences, since this layer is only detectable in narrow wavelength bands of very low methane absorption, but in Fig. 12 it can be seen that if we add a unit opacity of conservatively scattering particles to the Aerosol-2 layer at 1–2 bar (with the same Gamma size distribution as the Aerosol-2 particles, with mean radius 0.6 μm and variance σ = 0.3) the (I/F)₀ and k difference increases at all wavelengths longer than ∼ 480 nm (model X), although not as much as the difference between polar and equatorial latitudes. However, if we add this additional opacity and simultaneously halve the methane abundance (Model C1) we find that the differences in the (I/F)₀ and k spectra agree moderately well with the observed pole–equator difference spectra at most wavelengths. What might be responsible for this extra component of bright particles in the Aerosol-2 layer will be discussed further, but it could indicate that more methane ice particles are present in the haze/methane-ice layer, or that more methane ice is condensed onto the haze Cloud Condensation Nuclei (CCN). Whatever the cause, it is clear that the spectral difference between the polar and equatorial regions seen by HST/STIS in 2002 is consistent with a reduction in methane abundance coupled with an increase in the reflectivity of the particles in the Aerosol-2 layer that could be caused by the addition of a conservatively scattering component.

Having surveyed the possible interpretations of the HST/STIS polar and equatorial spectra, we then tested these models against the seasonal photometric magnitude data. While the Lowell Observatory magnitude data accurately preserve the quantities that were measured, they are a less intuitive measure for interpreting the changes in Uranus’s reflectivity spectrum with atmospheric models. Hence, we converted the magnitudes to the mean disc-averaged reflectivities of Uranus, which also corrects out the solid-angle variations of Uranus’s disc size, noted earlier. This conversion was done using the procedures outlined in Appendix B. The resulting seasonal variations in disc-averaged reflectivity at the blue and green wavelengths of the Strömgren b and y filters are shown in Fig. 13. Here, it can be seen that the disc-averaged green reflectivity of Uranus changes from ∼0.47 to ∼0.

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Who knew tweezers could get an upgrade? Check out how a smart ‘tweezer’ machine is changing the game by selectively harvesting beneficial bacteria in our latest article!

Researchers introduce mEnrich-seq, a game-changing approach in microbiome investigation. See how it detects elusive microbes like Akkermansia muciniphila.