Sal

Found this Saddleback Caterpillar (Acharia stimulea) in Yucatan, Mexico.

The hairs are allegedly capable of injecting venom with effects that can range from irritation and nausea all the way to severe reactions in rare circumstances. I did not test.

In this image you can see the actual head and eyes protruding from underneath its saddleback costume.

A more common view of this caterpillar is from its back side, where you can see its pretend "scary big eyes" that it uses to scare off some predators.

Here are some other viewpoints:

As my collection of small components grows, it is becoming... messy. And it is not even large yet, I have only done a handful of hobby projects.

Recently I had the realization that I can make use of Chinese 'Sample Books' to keep the smaller reel components well organized. I have ordered 0402, 0603, the 0805, and two empty books to use these as the basis of my organization:

What made me originally select the strategy of keeping the original packaging that the components came and stuffing them into project-specific bags is the labeling. My first attempt at organization was to to use small storage boxes for sorting, but when I tried to keep single labeled components per box I ran out of boxes very quickly... When I mix multiple components in a box (like different photodiodes, for example), then it is difficult to label them separately without using too much space.

I am curious about what methods others use for keeping a component library organized and easy to search.

The instance was updated today to v0.19.13

The official release notes can be found here: https://mander.xyz/post/37685278

The more noticeable frontend changes are:

Frontend

Don’t show edit mark if comment was edited in less than 5 minutes by @jfaustino #3197

Increase bio max length to 1000 chars by @nutomic #3249

Change link from element.io to matrix.org by @nutomic #3250

Remove all caches (fixes #3195) by @Nutomic in #3248

Fixed ordering for search results by @Nutomic in #3219

Add search field to community sidebar by @Nutomic in #3217

Add checkbox for title only search by @Nutomic in #3220

Abstract

The mid-infrared (MIR) photonics market is rapidly expanding, driven by advancements in fiber-based MIR devices, particularly fiber lasers. However, the lack of robust MIR optical fibers remains a critical barrier to further technological progress. In this work, we present the fabrication of gallate glasses containing tantalum oxide, as it stands, the most robust mid-infrared glasses capable of being easily shaped into large bulk components, fibers or tapers. By introducing up to 20 mol% of tantalum oxide in a gallate glass, we achieve a two-order-of-magnitude improvement in water corrosion resistance, while the nonlinear refractive index increases tenfold compared to silica. Optimal thermal stability is attained at 10 mol% of tantalum oxide, enabling the fabrication of tens-of-meter-long optical fibers. Crucially, the addition of tantalum oxide enhances the gallate glass properties without compromising thermomechanical performance. The potential of these tantalo-gallate glasses is further demonstrated through supercontinuum generation in a laser-inscribed waveguide and a tapered fiber, spanning from the visible to 4.5 μm. This work establishes our developed tantalo-gallate glasses as a compelling alternative for photonic applications seeking robust mid-infrared materials, with the potential to overcome the critical barriers currently limiting the advancement of fiber-based MIR technologies.

Abstract

Understanding the radiative decay of exciton-polaritons is essential for achieving long-lived polaritons - a key prerequisite for enhancing nonlinear and quantum polaritonic effects. However, conventional wisdom - the coupled oscillator model - often oversimplifies polariton radiation as independent emissions from uncoupled excitonic and photonic resonances, overlooking the role of strong exciton-photon coupling in reshaping their radiative behavior. In this work, we present a theoretical framework that goes beyond the conventional coupled oscillator model by fully accounting for the collective and coherent nature of exciton-photon interactions. We demonstrate that these interactions can strongly suppress polariton radiation via destructive interference - both within the excitonic ensemble and between excitonic and photonic radiation channels - giving rise to polaritonic bound states in the continuum with infinitely long radiative lifetimes. Our approach offers a unified description of polariton radiative decay and establishes new design principles for engineering long-lived exciton-polaritons with tailored radiation properties, opening new avenues for nonlinear, topological, and quantum polaritonic applications. 

Abstract

Optical phase modulation is essential for a wide range of silicon photonic integrated circuits used in communication applications. In this study, an optical phase shifter utilizing photo-elastic effects is proposed, where mechanical stress is induced by electrostatic micro-electro-mechanical systems (MEMS) with actuators arranged in a comb drive configuration. The design incorporates suspended serpentine silicon nitride (SiN) optical waveguides. Through extensive numerical simulations, it is shown that the change in the effective refractive index (neff) of the optical waveguide is a function of the voltage applied to the electrostatic actuators and that such neff tuning can be achieved for a broad range of wavelengths. Implemented within one arm of an unbalanced Mach–Zehnder interferometer (MZI), the phase shifter achieves a phase change of π when the stressed optical path measures 4.7 mm, and the actuators are supplied with 80 V DC and consume almost no power. This results in a half-wave voltage-length product (VπL) of 37.6 V·cm. Comparative analysis with contemporary optical phase shifters highlights the proposed design’s superior power efficiency, compact footprint, and simplified fabrication process, making it a highly efficient component for reconfigurable MEMS-based silicon nitride photonic integrated circuits.

Abstract

Animals often sustain injuries, which are susceptible to lethal infections. In social insects, wound care behaviours have evolved to reduce these risks. But the limits of wound care behaviours remain unclear. Here we investigated the wound care behaviours of the ant Camponotus maculatus. Our findings show that amputation of legs infected with Pseudomonas aeruginosa significantly reduced mortality. However, nestmates do not differentiate between infected and sterile injuries, providing similar treatments regardless of infection. Even though we show that early amputation correlates with higher survival rates, nestmates amputate indiscriminately on legs with fresh or old wounds. Additionally, cuticular hydrocarbon profiles differed between ants with infected or sterile wounds only 24 hours post-injury, a timepoint when amputations are no longer effective. We propose that C. maculatus workers perform prophylactic amputations regardless of injury state or age. This is in sharp contrast to previous studies which showed clear capabilities to treat infected wounds differently in ants using antimicrobial compounds. This work therefore shows the limits of wound care behaviours in social insects, allowing us to better understand the evolutionary drivers of this unique behaviour.

Abstract

Established by the 1971 United Nations (UN) Convention on Psychotropic Substances, the prohibition of the recreational use of psychedelics (lysergic acid diethylamide [LSD], psilocybin, N,N-dimethyltryptamine [N,N-DMT], and mescaline) has two premises. First, recreational use poses a serious threat to public health because psychedelics are highly liable to addiction and abuse. Second, psychedelics have only limited scientific and medical uses. In this article, we raise the following questions: are these premises true such that prohibition is justified? If not, are decriminalization and legal regulation justified alternatives? Drawing on interdisciplinary research, we show that the premises of prohibition are false. Psychedelics are not highly liable to addiction or abuse, and so recreational use is not a serious threat to public health. Moreover, the uses of psychedelics exceed medical and scientific uses. Prohibition, we conclude, is therefore unjustified. We then show that decriminalization is based on the same false premises as prohibition, that legal regulation is based on weaker versions of these premises, and thus that both alternatives entail unjustified restrictions on recreational users. Finally, we present a fourth approach: communalization. This entails that all adults have the freedom to recreationally use psychedelics without restrictions and that communities provide harm reduction and benefit enhancement services to support this freedom.

For reference, you can find the 1971 UN document here: https://www.unodc.org/pdf/convention_1971_en.pdf

Abstract

The evolution of adaptive innovations carries strong eco-evolutionary implications, allowing organisms to explore novel ecological opportunities, which facilitates lineage diversification. The remarkable diversity of reproductive strategies in amphibians provides a natural laboratory for identifying ecological mechanisms driving evolutionary novelties. In viviparous salamanders, the transition from larviparous (i.e., live bearing of aquatic larvae) to pueriparous (i.e., live bearing of fully terrestrial juveniles) reproduction is hypothesized to represent an adaptation to the absence of water for larval deposition, in what is known as the dry-climate hypothesis. This work aimed to identify the ecological drivers of independent evolutionary transitions to pueriparity and test the dry-climate hypothesis.

Main Conclusions

Reproductive transitions to pueriparity in salamanders were consistently associated with scarcity of surface water driven by steep topography and karstic geology, providing the most unambiguous support for the dry-climate hypothesis to date and supporting convergent evolution of terrestrialisation in salamanders for most pueriparous lineages. Climatic, hydrological (i.e., soil moisture and vapour pressure deficit) and habitat factors appear to be comparatively less relevant drivers of reproductive shifts, yet may have played a role in specific transitions to pueriparity, especially at the intraspecific level. We also found key differences in the use of available habitat between reproductive modes, with pueriparity representing a more specialised strategy likely restricted to areas with strong selective pressure against aquatic breeding.

Abstract

Nonenzymatic assembly of RNA from chemically activated building blocks, such as phosphorimidazolides, would have been essential for the emergence of ribozymes on the early Earth. We previously showed that ribonucleoside monophosphates can be activated to phosphorimidazolides via a potentially prebiotic phospho-Passerini reaction involving 2-aminoimidazole, 2-methylbutyraldehyde, and methyl isocyanide, and that these activated nucleotides enable template-directed nonenzymatic RNA polymerization in the same reaction mixture. Here, we demonstrate that the same chemistry activates oligoribonucleotides and drives both nonenzymatic and ribozyme-catalyzed RNA ligation within the same reaction environment. By demonstrating a continuous path from prebiotic activation chemistry to RNA template copying by both nonenzymatic and ribozyme-catalyzed ligation, our results provide a more integrated and realistic model for primordial RNA assembly.

Abstract

 Spin-lattice coupling is crucial for understanding the spin transport and dynamics for spintronics and magnonics applications. Recently, cobalt titanate (CoTiO3), an easy-plane antiferromagnet, has been found to host axial phonons with a large magnetic moment, which may originate from spin-lattice coupling. Here, we investigate the effect of light-driven lattice dynamics on the magnetic properties of CoTiO3 using time-resolved spectroscopy with a THz pump and a magneto-optic probe. We found resonantly driven Raman active phonons, phonon-polariton-induced excitation of the antiferromagnetic magnons, and a slow increase in the polarization rotation of the probe, all indicating symmetry breaking that is not intrinsic to the magnetic space group. The temperature dependence confirmed that the observed spin dynamics is related to the magnetic order, and we suggest surface effects as a possible mechanism. Our results of THz-induced spin-lattice dynamics signify that extrinsic symmetry breaking may contribute strongly and unexpectedly to light-driven phenomena in bulk complex oxides. 

Abstract

Estimating the plausibility of RNA self-reproduction is central to origin-of-life scenarios. However, this property has been shown in only a handful of catalytic RNAs. Here, we compare models for their generative power in diversifying a reference ribozyme, based on statistical covariation and secondary structure prediction, and experimentally test model predictions using high-throughput sequencing. Leveraging statistical physics methods, we compute the number of ribozymes capable of autocatalytic self-reproduction from oligonucleotide fragments to be over 1039, with sequences found up to 65 mutations from the original sequence and 99 mutations away from each other, far beyond the 10 mutations achieved by deep mutational scanning. The findings demonstrate an efficient method for exploring RNA sequence space, and provide quantitative data on self-reproducing RNA that further illuminates the potential pathways to abiogenesis.