We present the serendipitous radio-continuum discovery of a likely Galactic supernova remnant (SNR) G305.4–2.2. This object displays a remarkable circular symmetry in shape, making it one of the most circular Galactic SNRs known. Nicknamed Teleios due to its symmetry, it was detected in the new Australian Square Kilometre Array Pathfinder (ASKAP) Evolutionary Map of the Universe (EMU) radio–continuum images with an angular size of 1 320$^{\prime\prime}$$\times$1 260$^{\prime\prime}$ and PA = 0$^\circ$. While there is a hint of possible H$\alpha$ and gamma-ray emission, Teleios is exclusively seen at radio–continuum frequencies. Interestingly, Teleios is not only almost perfectly symmetric, but it also has one of the lowest surface brightnesses discovered among Galactic SNRs and a steep spectral index of $\alpha$=–0.6$\pm$0.3. Our best estimates from Hi studies and the $\Sigma$–D relation place Teleios as a type Ia SNR at a distance of either $\sim$2.2 kpc (near-side) or $\sim$7.7 kpc (far-side). This indicates two possible scenarios, either a young (under 1 000 yr) or a somewhat older SNR (over 10 000 yr). With a corresponding diameter of 14/48 pc, our evolutionary studies place Teleios at the either early or late Sedov phase, depending on the distance/diameter estimate. However, our modelling also predicts X-ray emission, which we do not see in the present generation of eROSITA images. We also explored a type Iax explosion scenario that would point to a much closer distance of $\lt$1 kpc and Teleios size of only $\sim$3.3 pc, which would be similar to the only known type Iax remnant SN1181. Unfortunately, all examined scenarios have their challenges, and no definitive Supernova (SN) origin type can be established at this stage. Remarkably, Teleios has retained its symmetrical shape as it aged even to such a diameter, suggesting expansion into a rarefied and isotropic ambient medium. The low radio surface brightness and the lack of pronounced polarisation can be explained by a high level of ambient rotation measure (RM), with the largest RM being observed at Teleios’s centre.

Sulfur stable isotope ratios (δ34S) have become increasingly common in archaeology for studying paleodiet, especially in occasions where there is a need to identify aquatic resource consumption more accurately. This is particularly relevant in the Baltic Sea region, where brackish conditions tend to mask “typical” marine carbon isotopic signals. Here we report new δ34S values for 126 human bone collagen samples which will be analyzed together with previously published data to investigate the potential of sulfur isotopes as an alternative proxy for aquatic resource consumption in historic period Estonia (ca. AD 1100‒1800). Bayesian statistical programming was used to provide quantitative dietary estimates, suggesting that the diet of the general population was predominantly terrestrial. The inclusion of δ34S as an additional dietary proxy produced generally comparable model results to the scenario that excluded δ34S. A sub-selection of samples was also radiocarbon dated and calibrated to take into account potential reservoir effects. For burials of commoners, the average contribution of 10% fish to dietary carbon does not significantly alter calibrated date ranges, even in the occasion where data on local reservoir effects is insufficient. This study has demonstrated both the potential and the pitfalls of using δ34S in this temporo-spatial context, and the new stable isotope and 14C data have shed light onto individual site-histories but also to broader cultural processes and changes that occurred during these turbulent times in this region.

Depression, a leading cause of global disability, arises from a multifaceted combination of genetic and environmental components. This study explores the relationship between major depressive disorder (MDD) polygenic scores (PGS), characteristics and symptoms of depression, and community-shared socioeconomic factors derived from postal code data in a cohort of 12,646 individuals from the Australian Genetics of Depression Study (AGDS). Our findings reveal that people living in areas with relatively higher socioeconomic advantages and education/occupation scores are more likely to report experiencing fewer depressive symptoms during their worst depressive period, as well as fewer number of lifetime episodes. Additionally, participants who reported depression onset later in life tend to currently reside in wealthier areas. Interestingly, no significant interaction between genetic and socioeconomic factors was observed, suggesting their independent contribution to depression outcomes. This research underscores the importance of integrating socioeconomic factors into psychiatric evaluation and care, and points to the critical role of public policy in addressing mental health disparities driven by socioeconomic factors. Future research should aim to further elucidate the causal relationships within these associations and explore the potential for integrated genetic and socioeconomic approaches in mental health interventions.

Measurements of the radiocarbon (14C) content of subannual wood cellulose samples over the 1963 bomb spike have revealed an apparent delay between the increase in atmospheric radiocarbon content and that of wood cellulose. This delay is apparent in both coniferous and deciduous tree species and is of a magnitude of approximately 4 weeks. The delay in wood cellulose 14C change as measured in a Sitka spruce from Washington state, USA, was previously used to estimate the relative influence of tree physiological effects contra environmental effects. We repeated the measurements with the increased measurement precision of today’s AMS systems and compare the new results to the ones of a Scots pine tree from Trondheim, central Norway and a white oak from Oregon state, USA. The results challenge the assumption that the 14C tree ring records directly show the atmospheric 14C concentration of a homogeneous, zonally well-mixed atmosphere. Instead, the apparent 1963 delay reflects local influences of the ecosystem and tree physiology. The 1963/1964 data allows for exploratory modeling of the effects of biospheric decay CO2 and local environmental influences assuming the absence of stored photosynthates from the previous year. Compared to the 10–30% contribution from biospheric CO2, the effects of delayed incorporation of carbon into the wood cellulose and the effect of stored photosynthate are small in the conifers. Highly detailed 14C records of stem cellulose can, in combination with stable isotope studies, contribute to our understanding of variability of the local carbon cycle, climate, and the environment.

The First Large Absorption Survey in H i (FLASH) is a large-area radio survey for neutral hydrogen in and around galaxies in the intermediate redshift range $0.4\lt z\lt1.0$, using the 21-cm H i absorption line as a probe of cold neutral gas. The survey uses the ASKAP radio telescope and will cover 24,000 deg$^2$ of sky over the next five years. FLASH breaks new ground in two ways – it is the first large H i absorption survey to be carried out without any optical preselection of targets, and we use an automated Bayesian line-finding tool to search through large datasets and assign a statistical significance to potential line detections. Two Pilot Surveys, covering around 3000 deg$^2$ of sky, were carried out in 2019-22 to test and verify the strategy for the full FLASH survey. The processed data products from these Pilot Surveys (spectral-line cubes, continuum images, and catalogues) are public and available online. In this paper, we describe the FLASH spectral-line and continuum data products and discuss the quality of the H i spectra and the completeness of our automated line search. Finally, we present a set of 30 new H i absorption lines that were robustly detected in the Pilot Surveys, almost doubling the number of known H i absorption systems at $0.4\lt z\lt1$. The detected lines span a wide range in H i optical depth, including three lines with a peak optical depth $\tau\gt1$, and appear to be a mixture of intervening and associated systems. Interestingly, around two-thirds of the lines found in this untargeted sample are detected against sources with a peaked-spectrum radio continuum, which are only a minor (5–20%) fraction of the overall radio-source population. The detection rate for H i absorption lines in the Pilot Surveys (0.3 to 0.5 lines per 40 deg$^2$ ASKAP field) is a factor of two below the expected value. One possible reason for this is the presence of a range of spectral-line artefacts in the Pilot Survey data that have now been mitigated and are not expected to recur in the full FLASH survey. A future paper in this series will discuss the host galaxies of the H i absorption systems identified here.

A major subglacial lake, Lake Snow Eagle (LSE), was identified in East Antarctica by airborne geophysical surveys. LSE, contained within a subglacial canyon, likely hosts a valuable sediment record of the geological and glaciological changes of interior East Antarctica. Understanding past lake activity is crucial for interpreting this record. Here, we present the englacial radiostratigraphy in the LSE area mapped by airborne ice-penetrating radar, which reveals a localized high-amplitude variation in ice unit thickness that is estimated to be ∼12 ka old. Using an ice-flow model that simulates englacial stratigraphy, we investigate the origin of this feature and its relationship to changes in ice dynamical boundary conditions. Our results reveal that local snowfall redistribution initiated around the early Holocene is likely the primary cause, resulting from a short-wavelength (∼10 km) high-amplitude (∼20 m) ice surface slope variation caused by basal lubrication over a large subglacial lake. This finding indicates an increase in LSE water volume during the Holocene, illustrating the sensitivity in volume of a major topographically constrained subglacial lake across a single glacial cycle. This study demonstrates how englacial stratigraphy can provide valuable insight into subglacial hydrological changes before modern satellite observations, both for LSE and potentially at other locations.

Objectives/Goals: Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer (BC) with limited treatment options. Mortality rate is especially high in African American (AA) women of reproductive age. High levels of intracellular calcium (Ca2+) have been shown in TNBC cells. This study is to investigate Ca2+ channel blockers (CCBs) as therapy for TNBC. Methods/Study Population: Two human TNBC cell lines obtained from ATCC – HCC1806, and MDA-MB-453 are treated with CCBs, Cilnidipine (Cil), and Mibefradil (Mib), in a concentration- and time-dependent manner. Cell proliferation assays are performed by the MTS cell viability assay. Intracellular Ca2+ levels are measured using the fluorescent dye: Fluro 4-AM. Apoptosis is determined by flow cytometry using Annexin V staining and mitochondrial permeability will be assessed by the Mito JC-1 assay. Expression of Ca2+ signaling genes will be quantitated by real-time polymerase chain reaction (RT-PCR). Potential pathways of CCB efficacy will be identified by ingenuity pathway analysis (IPA). Results/Anticipated Results: Our findings show both CCBs decrease cell proliferation in a concentration- and time-dependent manner to a maximum of 80% vs. control in both TNBC cells. Flow cytometry findings on both TNBC cells treated with both drugs at 20 µM for 24 hours depicts late apoptosis. Interestingly, Mib did not change the intracellular Ca2+ level in HCC1806 cells yet decreased in MDA-MB-453 cells by fivefold, while Cil increased the intracellular Ca2+ level in both cells almost twofold. It is anticipated that Mito JC-1 assay depict decreased mitochondrial potential in both cells. For reverse transcription polymerase chain reaction, it is anticipated that CCB treatment will increase transient receptor potential Ca2+ channels and decrease voltage-gated Ca2+ channels in both cells. IPA analysis is expected to show apoptotic pathways are involved in TNBC via CCB treatment. Discussion/Significance of Impact: TNBC lacks the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Treatment options for TNBC remain severely limited. Our findings that both Cil and Mib can inhibit proliferation of human breast cancer cell lines indicate repurposing CCBs as treatment for TNBC warrants further investigation.

This paper studies reversibility and transitivity of semigroups acting on homogeneous spaces. Properties of the reversor set of a subsemigroup acting on homogeneous spaces are presented. Let G be a topological group and L a subgroup of G. Assume that S is a subsemigroup of G with nonempty interior. It is presented a study of the reversibility of the S-action on $G/L$ in terms of the actions of S and L on homogeneous spaces of G. The results relate the reversibility and the transitivity of S in $G/L$ with the minimality of the action of L on homogeneous spaces of G. In addition, sufficient conditions for S to be right reversible in G if S is reversible in $G/L$ are presented.

In laboratory testing, a novel hydrogen peroxide gas plasma endoscope sterilizer consistently reduced vegetative organisms, but not bacterial spores, to undetectable levels in the presence of high organism load (≥6.5 log10) and organic material and salts. These findings highlight the importance of meticulous cleaning of endoscopes prior to sterilization.

The strategy method (SM) is, in practice, subject to a possibly severe economic-theoretical bias. Although many studies utilize SM to examine responses to rare or off-equilibrium behaviors unattainable through direct elicitation (DE), they ignore the fact that the strategic equivalence between SM and DE holds for the monetary payoff game but not the game participants actually play, which is in terms of utilities. We report three results. First, failing to account for estimation bias when decisions at one information set can influence utility at another may result in significant differences in decision-making. Second, the magnitude of this bias can be substantial, comparable to other measured treatment effects. Third, minor interventions targeting salience can amplify these differences similarly, causing treatment effects to differ significantly between SM and DE, even reversing in direction. These findings emphasize the need for reconsideration of the SM’s reliability for economic research.

This article highlights a potential and significant economic–theoretical bias in the widely used strategy method (SM) technique. Although SM is commonly employed to analyze numerous observations per subject regarding rare or off-equilibrium behaviors unattainable through direct elicitation (DE), researchers often overlook a critical distinction. The strategic equivalence between SM and DE is applicable in the context of monetary payoff games, but not in the actual utility-based games played by participants. This oversight may lead to inaccurate conclusions and demand a reevaluation of existing research in the field. We formalize the mapping from the monetary payoff game to this actual game and delineate necessary and sufficient conditions for strategic equivalence to apply.