Topology of the Spin-polarized Charge Density in bcc and fcc Iron

We investigate the topology of the spin-polarized charge density in bcc and fcc iron. While the total spin-density is found to possess the topology of the non-magnetic prototypical structures, in some cases the spin-polarized densities are characterized by unique topologies; for example, the spin-polarized charge densities of bcc and high-spin fcc iron are atypical of any known for non-magnetic materials. In these cases, the two spin-densities are correlated: the spin-minority electrons have directional bond paths with deep minima in the minority density, while the spin-majority electrons fill these holes, reducing bond directionality. The presence of two distinct spin topologies suggests that a well-known magnetic phase transition in iron can be fruitfully reexamined in light of these topological changes. We show that the two phase changes seen in fcc iron (paramagnetic to low-spin and low-spin to high-spin) are different. The former follows the Landau symmetry-breaking paradigm and proceeds without a topological transformation, while the latter also involves a topological catastrophe.Comment: 5 pages, 3 figures. Phys. Rev. Lett. (in press

Electronic Selection Rules Controlling Dislocation Glide in bcc Metals

The validity of the structure-property relationships governing the deformation behavior of bcc metals was brought into question with recent {\it ab initio} density functional studies of isolated screw dislocations in Mo and Ta. These existing relationships were semiclassical in nature, having grown from atomistic investigations of the deformation properties of the groups V and VI transition metals. We find that the correct form for these structure-property relationships is fully quantum mechanical, involving the coupling of electronic states with the strain field at the core of long $a/2$ screw dislocations.Comment: 4 pages, 2 figure

A Novel, Contactless, Portable “Spot-Check” Device Accurately Measures Respiratory Rate

Respiratory rate (RR) is an important vital sign used in the assessment of acutely ill patients. It is also used as to predict serious deterioration in a patient's clinical condition. Convenient electronic devices exist for measurement of pulse, blood pressure, oxygen saturation and temperature. Although devices which measure RR exist, none has entered everyday clinical practice. We developed a contactless portable respiratory rate monitor (CPRM) and evaluated the agreement in respiratory rate measurements between existing methods and our new device. The CPRM uses thermal anemometry to measure breath signals during inspiration and expiration. RR data were collected from 52 healthy adult volunteers using respiratory inductance plethysmography (RIP) bands (established contact method), visual counting of chest movements (established non-contact method) and the CPRM (new method), simultaneously. Two differently shaped funnel attachments were evaluated for each volunteer. Data showed good agreement between measurements from the CPRM and the gold standard RIP, with intra-class correlation coefficient (ICC): 0.836, mean difference 0.46 and 95% limits of agreement of -5.90 to 6.83. When separate air inlet funnels of the CPRM were analysed, stronger agreement was seen with an elliptical air inlet; ICC 0.908, mean difference 0.37 with 95% limits of agreement -4.35 to 5.08. A contactless device for accurately and quickly measuring respiratory rate will be an important triage tool in the clinical assessment of patients. More testing is needed to explore the reasons for outlying measurements and to evaluate in the clinical setting

Injury Incidence and Prevalence in a Sample of Wrestlers Based in Britain: A Retrospective Study Journal of Elite Sport Performance

Background and Aim Britain has competed in Freestyle Wrestling since it first featured in the Olympic Games in 1904 and the Commonwealth Games in 1930. Despite Britain’s long history with the sport, there are currently no studies that have aimed to quantify injury incidence and prevalence. Therefore, the aim of this study was to estimate the injury incidence and prevalence in a sample of wrestlers based in Britain. Methods A self-reported, cross-sectional study design was used. All participants were registered British Wrestling Association Club members and had at least 12 months of prior wrestling experience. Data was collected via a questionnaire offered to participants in both online and paper format at the English Wrestling Championships 2022 and via coaches from each British wrestling club. Injury incidence was calculated by estimating injuries /1000 athletic exposures (AE). Injury site, type, mechanism and severity were measured. One variable chi-square tests (X2) were used to calculate if observed values were significantly different from expected values. Results One hundred and forty-six (n=146) wrestlers (30.1 ± 8.6 years, 85.4 ± 15.6 kg, 176.6 ±10.37cm) completed the injury survey. Over 12 months, the participants sustained one hundred and ninety-five (n= 195) injuries, equating to an average of 1.3 ± 1.2 per participant. The overall incidence rate was 3.40/1000 AE (95% CI 3.16 to 3.6). The competition injury incidence of 42.01/1000 AE (95% CI 26.97 to 57.05) and 2.92/1000 AE (95% CI 2.69 to 3.14) for wrestling training activities. The knee was the most common injury site, accounting for 26.1% of all injuries, whilst strains or sprains occurred most often (36.3%). Takedowns were the leading mechanism of injury (36.4%), and most injuries were categorised as slight (28.7%). Conclusions This is the first study to estimate the prevalence, severity, and mechanism of injury in Wrestlers based in Britain. Data is comparable to previous studies in American high school and college wrestlers. Future studies should consider a medically reported method to confirm these results further. Practical Implications The reported data from this study allows for the development of injury risk reduction strategies by region and injury type

Combining role-play with interactive simulation to motivate informed climate action: Evidence from the World Climate simulation

Climate change communication efforts grounded in the information deficit model have largely failed to close the gap between scientific and public understanding of the risks posed by climate change. In response, simulations have been proposed to enable people to learn for themselves about this complex and politically charged topic. Here we assess the impact of a widely-used simulation, World Climate, which combines a socially and emotionally engaging role-play with interactive exploration of climate change science through the C-ROADS climate simulation model. Participants take on the roles of delegates to the UN climate negotiations and are challenged to create an agreement that meets international climate goals. Their decisions are entered into C-ROADS, which provides immediate feedback about expected global climate impacts, enabling them to learn about climate change while experiencing the social dynamics of negotiations. We assess the impact of World Climate by analyzing pre- and post-survey results from >2,000 participants in 39 sessions in eight nations. We find statistically significant gains in three areas: (i) knowledge of climate change causes, dynamics and impacts; (ii) affective engagement including greater feelings of urgency and hope; and (iii) a desire to learn and do more about climate change. Contrary to the deficit model, gains in urgency were associated with gains in participants’ desire to learn more and intent to act, while gains in climate knowledge were not. Gains were just as strong among American participants who oppose government regulation of free markets–a political ideology that has been linked to climate change denial in the US–suggesting the simulation’s potential to reach across political divides. The results indicate that World Climate offers a climate change communication tool that enables people to learn and feel for themselves, which together have the potential to motivate action informed by science.National Science Foundation (U.S.) (grant DUE-124558)National Science Foundation (U.S.) (grant ICEER-1701062

Divisia Second Moments

W. A. Barnett originated the Divisia monetary aggregates, using Diewert's results on superlative index numbers and Barnett's derivation of the user cost of monetary asset services. The resulting Divisia index can be interpreted as a first moment aggregating over growth rates with expenditure shares serving as probabilities. But Theil showed that there are analogous higher order Divisia moments providing distributional information. In this paper we use the Divisia second moments to investigate distributional information in the monetary aggregate growth rates

Divisia Second Moments: An Application of Stochastic Index Number Theory

W. A. Barnett originated the Divisia monetary aggregates, using Diewert's results on superlative index numbers and Barnett's derivation of the user cost of monetary asset services. The resulting Divisia index can be interpreted as a first moment aggregating over growth rates with expenditure shares serving as probabilities. But Theil showed that there are analogous higher order Divisia moments providing distributional information. In this paper we use the Divisia second moments to investigate distributional information in the monetary aggregate growth rates and to measure aggregation error in the Divisia first moments

Divisia Second Moments: An Application of Stochastic Index Number Theory

W. A. Barnett originated the Divisia monetary aggregates, using Diewert's results on superlative index numbers and Barnett's derivation of the user cost of monetary asset services. The resulting Divisia index can be interpreted as a first moment aggregating over growth rates with expenditure shares serving as probabilities. But Theil showed that there are analogous higher order Divisia moments providing distributional information. In this paper we use the Divisia second moments to investigate distributional information in the monetary aggregate growth rates and to measure aggregation error in the Divisia first moments

A Novel Micropeptide, \u3cem\u3eSlitharin\u3c/em\u3e, Exerts Cardioprotective Effects in Myocardial Infarction

Purpose: Micropeptides are an emerging class of proteins that play critical roles in cell signaling. Here, we describe the discovery of a novel micropeptide, dubbed slitharin (Slt), in conditioned media from Cardiosphere-derived cells (CDCs), a therapeutic cardiac stromal cell type. Experimental design: We performed mass spectrometry of peptide-enriched fractions from the conditioned media of CDCs and a therapeutically inert cell type (human dermal fibrobasts). We then evaluated the therapeutic capacity of the candidate peptide using an in vitro model of cardiomyocyte injury and a rat model of myocardial infarction. Results: We identified a novel 24-amino acid micropeptide (dubbed Slitharin [Slt]) with a non-canonical leucine start codon, arising from long intergenic non-coding (LINC) RNA 2099. Neonatal rat ventricular myocytes (NRVMs) exposed to Slt were protected from hypoxic injury in vitro compared to a vehicle or scrambled control. Transcriptomic analysis of cardiomyocytes exposed to Slt reveals cytoprotective capacity, putatively through regulation of stress-induced MAPK-ERK. Slt also exerted cardioprotective effects in rats with myocardial infarction as shown by reduced infarct size 48 h post-injury. Conclusions and clinical relavance: Thus, Slt is a non-coding RNA-derived micropeptide, identified in the extracellular space, with a potential cardioprotective function