Hexagon-singlet solid ansatz for the spin-1 kagome antiferromagnet

We perform a systematic investigation on the hexagon-singlet solid (HSS) states, which are a class of spin liquid candidates for the spin-1 kagome antiferromagnet. With the Schwinger boson representation, we show that all HSS states have exponentially decaying correlations and can be interpreted as a (special) subset of the resonating Affleck-Kennedy-Lieb-Tasaki (AKLT) loop states. We provide a compact tensor network representation of the HSS states, with which we are able to calculate physical observables efficiently. We find that the HSS states have vanishing topological entanglement entropy, suggesting the absence of intrinsic topological order. We also employ the HSS states to perform a variational study of the spin-1 kagome Heisenberg antiferromagnetic model. When we use a restricted HSS ansatz preserving lattice symmetry, the best variational energy per site is found to be $e_0 = -1.3600$. In contrast, when allowing lattice symmetry breaking, we find a trimerized simplex valence bond crystal with a lower energy, $e_0=-1.3871$.Comment: 14 pages, 12 figures, published versio

Investigating Dielectric Properties of Sintered Polymers for Rapid Manufacturing

Selective Laser Sintering (SLS) of polymers is the leading technology in the growing field of Rapid Manufacturing. High Speed Sintering (HSS) is a process that offers the potential to reduce costs and processing times and thus open significant new markets for Rapid Manufactured parts. Much academic research has been performed with respect to mechanical properties of Rapid Manufactured parts, however the area of electrical properties has received little attention to date. Electrical properties are obviously important in applications that will involve embedding of circuits with Rapid Manufactured 3D objects. However electrical properties are also important for a wide variety of electrical products where Rapid Manufactured parts can be used as housings etc. This paper focuses on the dielectric properties of parts made by SLS and HSS and compares properties with those for conventionally processed polymers. Dielectric strength results show that SLS parts are comparable with injection moulded parts, while HSS parts are inferior to SLS parts. Dielectric constant and dissipation factor results show that HSS parts are comparable with injection moulded parts, whilst SLS parts have superior properties. The presence of porosity (SLS and HSS) and the presence of carbon (HSS) are suggested as reasons behind the variation in dielectric properties when compared with injection moulded parts.Mechanical Engineerin

A 2-Question Summative Score Correlates with the Maslach Burnout Inventory

Introduction: There is a high prevalence of burnout among emergency medicine (EM) residents. The Maslach Burnout Inventory - Human Services Survey (MBI-HSS) is a widely used tool to measure burnout. The objective of this study was to compare the MBI-HSS and a two-question tool to determine burnout in the EM resident population.Methods: Based on data from the 2017 National Emergency Medicine Resident Wellness Survey study, we determined the correlation between two single-item questions with their respective MBI subscales and the full MBI-HSS. We then compared a 2-Question Summative Score to the full MBI-HSS with respect to primary, more restrictive, and more inclusive definitions of burnout previously reported in the literature.Results: Of 1,522 residents who completed the survey 37.0% reported “I feel burned out from my work,” and 47.1% reported “I have become more callous toward people since I took this job” once a week or more (each item >3 on a scale of 0-6). A 2-Question Summative Score totaling >3 correlated most closely with the primary definition of burnout (Spearman’s rho 0.65 [95% confidence interval 0.62-0.68]). Using the summative score, 77.7% of residents were identified as burned out, compared to 76.1% using the full MBI-HSS, with a sensitivity and specificity of 93.6% and 73.0%, respectively.Conclusion: An abbreviated 2-Question Summative Score correlates well with the full MBI-HSS tool in assessing EM resident physician burnout and could be considered a rapid screening tool to identify at-risk residents experiencing burnout

A Worker Dialogue: Improving Health Safety and Security at DOE

During the summer of 2010, the Department of Energy Office of Health, Safety and Security (HSS) partnered with the National Academy of Public Administration to host an online dialogue to solicit ideas from front line union workers at DOE sites on how to improve worker safety across the DOE complex. Based on the results of the Dialogue, an expert Panel of the National Academy identified several themes that emerged from workers' suggestions and offered recommendations for HSS in following up on the issues raised as well as continuing to build its capacity for employee engagement.Key FindingsBased specifically on the Dialogue results, the Panel recommended HSS further investigate several issues and claims discussed by workers as well as assess the current state of reporting processes in DOE to determine if changes are necessary. In addition, the Dialogue revealed many knowledge gaps among workers regarding the substance of worker health and safety regulations in DOE, which should prompt HSS to consider expanding efforts to educate workers about these regulations.The Panel also issued several recommendations for HSS to build its capacity to engage union workers. These recommendations included considering alternate channels of reaching front-line workers and continuing engagement with workers by articulating and undertaking concrete next steps with the input received