Lessons from LHC elastic and diffractive data

We discuss a model which gives a `global' description of the wide variety of high-energy elastic and diffractive data that are presently available, particularly from the LHC experiments. The model is based on only one pomeron pole, but includes multi-pomeron interactions. Significantly, the LHC measurements require that the model includes the transverse momentum dependence of the intermediate partons as a function of their rapidity, which results in a rapidity (or energy) dependence of the multi-pomeron vertices.Comment: 9 pages, 2 figures, To be published in the Proceedings of the International Workshop on Particle Physics Phenomenology in memory of Alexei Kaidalov, Moscow, 21-25 July, 201

Updates of PDFs for the 2nd LHC run

I present results on continuing updates in PDFs within the framework now called MMHT14 due to both theory improvements and the inclusion of new data sets, including most of the up-to-date LHC data. A new set of PDFs is essentially finalised, with no changes expected to the PDFs presented here.Comment: 6 pages, 5 figures. Proceedings of the 37th International Conference of High-Energy Physics (ICHEP2014), 2-9 July 2014, Valencia, Spai

Supercoherent states and physical systems

A method is developed for obtaining coherent states of a system admitting a supersymmetry. These states are called supercoherent states. The presented approach is based on an extension to supergroups of the usual group-theoretic approach. The example of the supersymmetric harmonic oscillator is discussed, thereby illustrating some of the attractive features of the method. Supercoherent states of an electron moving in a constant magnetic field are also described

Design of a microwave radiometer for monitoring high voltage insulator contamination level

Microwave radiometry is a novel method for monitoring contamination levels on high voltage insulators. The microwave radiometer described measures energy emitted from the contamination layer and could provide a safe, reliable, contactless monitoring method that is effective under dry conditions. The design of the system has focused on optimizing accuracy, stability and sensitivity using a relatively low cost architecture. Experimental results demonstrate that the output from the radiometer is able to clearly distinguish between samples with different contamination levels under dry conditions. This contamination monitoring method could potentially provide advance warning of the future failure of wet insulators in climates where insulators can experience dry conditions for extended periods

Defective spermatogenesis: Martin et al. respond

This is an Open Access article - Copyright @ National Institute of Environmental Health Science.BACKGROUND: Male reproductive tract abnormalities such as hypospadias and cryptorchidism, and testicular cancer have been proposed to comprise a common syndrome together with impaired spermatogenesis with a common etiology resulting from the disruption of gonadal development during fetal life, the testicular dysgenesis syndrome (TDS). The hypothesis that in utero exposure to estrogenic agents could induce these disorders was first proposed in 1993. The only quantitative summary estimate of the association between prenatal exposure to estrogenic agents and testicular cancer was published over 10 years ago, and other systematic reviews of the association between estrogenic compounds, other than the potent pharmaceutical estrogen diethylstilbestrol (DES), and TDS end points have remained inconclusive. OBJECTIVES: We conducted a quantitative meta-analysis of the association between the end points related to TDS and prenatal exposure to estrogenic agents. Inclusion in this analysis was based on mechanistic criteria, and the plausibility of an estrogen receptor (ER)-α–mediated mode of action was specifically explored. RESULTS: We included in this meta-analysis eight studies investigating the etiology of hypospadias and/or cryptorchidism that had not been identified in previous systematic reviews. Four additional studies of pharmaceutical estrogens yielded a statistically significant updated summary estimate for testicular cancer. CONCLUSIONS: The doubling of the risk ratios for all three end points investigated after DES exposure is consistent with a shared etiology and the TDS hypothesis but does not constitute evidence of an estrogenic mode of action. Results of the subset analyses point to the existence of unidentified sources of heterogeneity between studies or within the study population

The Calibration of the HST Kuiper Belt Object Search: Setting the Record Straight

The limiting magnitude of the HST data set used by Cochran et al. (1995) to detect small objects in the Kuiper belt is reevaluated, and the methods used are described in detail. It is shown, by implanting artificial objects in the original HST images, and re-reducing the images using our original algorithm, that the limiting magnitude of our images (as defined by the 50% detectability limit) is $V=28.4$. This value is statistically the same as the value found in the original analysis. We find that $\sim50$ of the moving Kuiper belt objects with $V=27.9$ are detected when trailing losses are included. In the same data in which these faint objects are detected, we find that the number of false detections brighter than $V=28.8$ is less than one per WFPC2 image. We show that, primarily due to a zero-point calibration error, but partly due to inadequacies in modeling the HST'S data noise characteristics and Cochran et al.'s reduction techniques, Brown et al. 1997 underestimate the SNR of objects in the HST dataset by over a factor of 2, and their conclusions are therefore invalid.Comment: Accepted to ApJ Letters; 10 pages plus 3 figures, LaTe

Real-world connections to sustainability: Using authentic learning activities to introduce students to systems thinking through green chemistry

Systems thinking refers to approaches to learning that emphasise the interdependence of components in dynamic systems and how they interact and influence one another (Mahaffy et al., 2019). Applying systems thinking to green chemistry teaching and learning can create a molecular basis for sustainability (Mahaffy et al., 2019) that is able to enhance undergraduate chemistry students’ multidimensional understanding of complex sustainability challenges (Smith, 2011). However, efforts to introduce sustainable systems thinking – specifically within first-year introductory chemistry courses – are particularly challenging, and past approaches have produced mixed success (Mahaffy et al., 2019; An et al., 2021). Consequently, this indicates an opportune space within undergraduate chemistry education research to explore alternative and multidisciplinary approaches towards teaching green chemistry and sustainability (Wissinger et al., 2021). In this research, we present the preliminary results of a trimester-long intervention using authentic learning activities to introduce first-year chemistry students to systems thinking, through the application of green chemistry concepts. To determine the effectiveness of the intervention, we are using a mixed-methods research design to assess the impact of the learning activities on students’ development of systems thinking skills. Student motivations and attitudes towards the subject of chemistry will also be evaluated via validated survey instruments (Guay et al., 2000; Liu et al., 2017). The learning activities have been designed and developed successfully, though the delivery of the intervention is currently ongoing. Preliminary results indicate that students are excited to learn about how chemistry can be more sustainable, and that they are engaging with the learning activities. The aim of this research is to provide rigorous evidence for using systems thinking as a tool to teach students about green chemistry, ‘future-proofing’ chemistry in a way that is relevant, meaningful, and authentic for today’s chemistry students. Outcomes from our data analysis will help inform the development of new undergraduate chemistry education curricula that align with contemporary sustainable challenges. REFERENCES An, J., Loppnow, G.R., & Holme, T. A. (2021). Measuring the impact of incorporating systems thinking into general chemistry on affective components of student learning. Canadian Journal of Chemistry, 99(8), 698–705. Fisher, M.A. (2019). Systems thinking and educating the heads, hands, and hearts of chemistry majors. Journal of Chemical Education, 96(12), 2715–2719. Guay, F., Vallerand, R. J., & Blanchard, C. (2000). On the assessment of situational intrinsic and extrinsic motivation: The Situational Motivation Scale (SIMS). Motivation and emotion, 24(3), 175–213. Liu, Y., Ferrell, B., Barbera, J., & Lewis, J. E. (2017). Development and evaluation of a chemistry-specific version of the academic motivation scale (AMS-Chemistry). Chemistry Education Research and Practice, 18(1), 191–213. Mahaffy, P. G., Matlin, S. A., Holme, T. A., & MacKellar, J. (2019). Systems thinking for education about the molecular basis of sustainability. Nature Sustainability, 2(5), 362–370. Smith, T. (2011). Using critical systems thinking to foster an integrated approach to sustainability: A proposal for development practitioners. Environment, development and sustainability, 13, 1–17. Wissinger, J. E., Visa, A., Saha, B. B., Matlin, S. A., Mahaffy, P. G., Kümmerer, K., & Cornell, S. (2021). Integrating sustainability into learning in chemistry. Journal of Chemical Education, 98(4), 1061–1063

The effects of river flooding on dioxin and PCBs in beef

In 2008-2010, samples of meat from 40 beef cattle, along with grass, soil and commercial feed, taken from ten matched pairs of flood-prone and control farms, were analysed for PCDD/Fs and PCBs. Concentrations were higher in soil and grass from flood-prone farms. The beef samples from flood-prone farms had total TEQ levels about 20% higher than on control farms. A majority of flood-prone farms (7/10) had higher median levels in beef than on the corresponding control farm. This first controlled investigation into PCDD/F and PCB contamination in beef produced on flood-prone land, presents robust evidence that flooding is a contaminant transfer mechanism to cattle raised on river catchments with a history of urbanisation and industrialisation. PCDD/F and PCB sources in these river systems are likely to be a result of the legacy of contamination from previous industrialisation, as well as more recent combustion activity or pollution events. Crow