SN 1988Z: Spectro-photometric catalogue and energy estimates

We present a spectro-photometric catalogue of the evolution of supernova 1988Z which combines new and published observations in the radio, optical and X-ray bands, with the aim of offering a comprehensive view of the evolution of this object and deriving the total energy radiated since discovery. The major contribution to the total radiated energy comes at optical to X-ray frequencies, with a total emission of at least $2 \times 10^{51}$ erg (for Ho=50 km/s) in 8.5 years. A model-dependent extrapolation of this value indicates that the total radiated energy may be as high as $10^{52}$ erg. The high value of the radiated energy supports a scenario in which most of the kinetic energy of the ejecta is thermalized and radiated in a short interaction with a dense circumstellar medium of nearly constant density. In this sense, 1988Z is not a supernova but a young and compact supernova remnant.Comment: Accepted to be published in MNRAS (14 pages, 10 figures). Also available at http://www.inaoep.mx/~itzia

Retroviral Expression of Transforming Growth Factor-Alpha Does Not Transform Fibroblasts or Keratinocytes

Transforming growth factor α (TGFα) is a peptide so named because it helps to impart anchorage-independent growth to normal rat kidney (NRK) cells in vitro and is secreted by many rodent and human tumor cells. To directly investigate the transforming properties of this factor, we constructed a replication-defective murine retrovirus that expresses the human sequence coding for TGFα. infection of NIH/3T3 cells with the TGFα retrovirus led to the integration of a transcriptionally active provirus and overexpression of biologically active TGFα, but failed to induce morphologic transformation. Similarly, the TGFα retrovirus failed to induce morphologic transformation of five other types of rodent fibroblasts.We also investigated the effect of TGFα expression on the growth of BALB/MK mouse keratinocytes, which require epidermal growth factor (EGF) for proliferation. We show that exogenously added TGFα is an extremely potent mitogen for BALB/MK cells. However, retroviral expression of TGFa in BALB/MK cells failed to relieve dependence on exogenously added EGF (or TGFα) for cell growth. These results suggest that overexpression of TGFα does not, by itself, transform rodent fibroblasts or keratinocytes

Understanding Virtual Nodes: Oversmoothing, Oversquashing, and Node Heterogeneity

Message passing neural networks (MPNNs) have been shown to have limitations in terms of expressivity and modeling long-range interactions. Augmenting MPNNs with a virtual node (VN) removes the locality constraint of the layer aggregation and has been found to improve performance on a range of benchmarks. We provide a comprehensive theoretical analysis of the role of VNs and benefits thereof, through the lenses of oversmoothing, oversquashing, and sensitivity analysis. First, in contrast to prior belief, we find that VNs typically avoid replicating anti-smoothing approaches to maintain expressive power. Second, we characterize, precisely, how the improvement afforded by VNs on the mixing abilities of the network and hence in mitigating oversquashing, depends on the underlying topology. Finally, we highlight that, unlike Graph-Transformers (GT), classical instantiations of the VN are often constrained to assign uniform importance to different nodes. Consequently, we propose a variant of VN with the same computational complexity, which can have different sensitivity to nodes based on the graph structure. We show that this is an extremely effective and computationally efficient baseline on graph-level tasks

Influence of flow containment and substrate entrainment upon sandy hybrid event beds containing a co-genetic mud-clast-rich division

Individual sandstone beds containing a co-genetic mud-clast-rich (MCR) division are being increasingly described from the distal reaches of many deep-water fan systems. These deposits, termed hybrid event beds, are considered to record a flow whose composition and rheology changed significantly to become increasingly more argillaceous (clay-rich), MCR and turbulence-suppressed during the deposition of a single event bed. Studies of confined systems, in which gravity flows were affected by confining sea-floor topography, have documented similar deposits recording turbulence suppression in proximity to confining sea-floor topography (e.g., basin margins). In new research from a confined, contained system from the Castagnola Basin of NW Italy, lateral transects of individual sandstone beds 5 km in extent show that individual sandstone beds contain a co-genetic MCR division which is often; 1) extensive across the basin rather than localised adjacent to confining topography; 2) exhibits rapid, significant and repeated variation in depositional character over short length scales (tens to hundreds of metres), specifically in terms of the thickness of co-genetic MCR divisions and the size and abundance of clasts contained within them; and 3) exhibits variation in depositional character over larger length scales (> 1 km) which is non-systematic in relation to palaeoflow direction or increasing proximity towards the counter slope of the downstream confining northern basin margin. A suite of factors within the Castagnola Basin is thought to have resulted in the deposition of these co-genetic MCR divisions whose thickness and distribution are less predictable in relation to confining sea-floor topography than those described from other confined uncontained settings. Specific factors include; 1) recent and voluminous entrainment of muddy substrate at seemingly random locations across the basin floor and their support and transport within a high sediment concentration gravity flow; and 2) containment (ponding) of gravity flows within a confined basin, which is thought to have established extensive and complex three dimensional flow dynamics across the basin following flow interaction with multiple basin margins. This research highlights the role of entrainment of muddy substrate and subsequent transport processes of muddy substrate for developing co-genetic MCR divisions, as well as the importance of understanding the degree of containment depositional systems experienced when considering the spatial distribution of depositional facies, and thus reservoir quality, in topographically complex settings

Exploring the development of early career nurses: insights 4 years after graduation

Aim To explore how Early Career Nurses perceive their preparedness for nursing practice, the teaching and learning experiences, and the role of professional experience placements on their professional development. Design A qualitative study using a hermeneutic phenomenological approach. Method The study involved 25 Early Career Nurses who participated in follow-up interviews 4 years post-graduation in Australia between 2022 and 2024. Data were collected through semi-structured interviews and analysed using Thematic Analysis. Results Three key themes emerged: gaps in preparedness, the power of being embedded and too many balls to juggle. Participants indicated a mixed sense of preparedness with significant gaps in clinical skills. They emphasised the critical role of professional experience placements and mentorship to bridge the gap between theoretical knowledge and practical application. Placements and mentorship opportunities were considered essential to develop confidence and competence for effective nursing practice. Conclusion The study highlights the necessity for nursing curricula to address significant gaps in clinical skills, particularly in surgical and emergency nursing. By incorporating more simulation-based learning, interprofessional education and robust mentorship programmes, nursing education can better prepare graduates for the realities of clinical practice. These enhancements will help ease the transition from academic training to clinical practice, reducing reality shock and fostering a more confident, competent and resilient nursing workforce