Experimental Measurements of Binder Wave Speeds using Wavenumber Decomposition

Prior work has provided few wave speed measurements for the binder materials commonly used with plastic- bonded energetics. Furthermore, those measurements that have been reported are largely based upon rudimentary, \u27pitch and catch\u27 methodologies, which involve sending a pulse from one transducer to another transducer at a set distance apart and measuring the time of flight. Given this, a more rigorous method for determining longitudinal and shear wave speeds in this important class of materials was desired. In this work, material wave speeds are recovered by measuring the vibrational response of a 2D line across the surface of a beam in response to a mechanical excitation and analyzing the data in the frequency-wavenumber domain

Primary progressive aphasia: a clinical approach

This work was supported by the Alzheimer’s Society (AS-PG-16-007), the National Institute for Health Research University College London Hospitals Biomedical Research Centre and the UCL Leonard Wolfson Experimental Neurology Centre (PR/ylr/18575). Individual authors were supported by the Leonard Wolfson Foundation (Clinical Research Fellowship to CRM), the National Institute for Health Research (NIHR Doctoral Training Fellowship to AV), the National Brain Appeal–Frontotemporal Dementia Research Fund (CNC) and the Medical Research Council (PhD Studentships to CJDH and RLB, MRC Research Training Fellowship to PDF, MRC Clinician Scientist to JDR). MNR and NCF are NIHR Senior Investigators. SJC is supported by Grants from ESRC-NIHR (ES/L001810/1), EPSRC (EP/M006093/1) and Wellcome Trust (200783). JDW was supported by a Wellcome Trust Senior Research Fellowship in Clinical Science (091673/Z/10/Z)

Uptake and Transfer of Polyamide Microplastics in a Freshwater Mesocosm Study

Steadily increasing inputs of microplastics pose a growing threat to aquatic fauna, but laboratory studies potentially lack realism to properly investigate its effects on populations and ecosystems. Our study investigates the trophic and ontogenetic transfer of microplastics in a near-natural exposure scenario. The controlled outdoor freshwater mesocosms were exposed to polyamide (PA) 5–50 µm in size in concentrations of 15 and 150 mg L−1 and a control without microplastic addition. To verify the uptake of particles via the food chain, larvae and imagines of the midges Chaoborus crystallinus and C. obscuripes were examined, which feed on zooplankton during their larval stage. Larvae were captured after 117 days and imagines were caught in emergence traps that were emptied weekly. To detect the microparticles within the organisms, 200 larvae and 100 imagines per application were macerated and treated with fluorescent dye before investigation under a fluorescent microscope. We could detect up to 12 PA particles per individual larvae, while nearly no plastic was found in the imagines. This shows that, while Chaoborus sp. takes up microplastics via predation, most of the pollutant is egested through regurgitation and remains in the water, where it can further accumulate and potentially harm other organisms

Identifying key elements for paediatric advance care planning with parents, healthcare providers and stakeholders: A qualitative study

Background: Although international guidelines recommend discussions about goals of care and treatment options for children with severe and life-limiting conditions, there are still few structured models of paediatric advance care planning. Aim: The study aimed at identifying key components of paediatric advance care planning through direct discussions with all involved parties. Design: The study had a qualitative design with a participatory approach. Participants constituted an advisory board and took part in two transdisciplinary workshops. Data were collected in discussion and dialogue groups and analysed using content analysis. Setting/participants: We included bereaved parents, health care providers and stakeholders of care networks. Results: Key elements were discussions, documentation, implementation, timing and participation of children and adolescents. Parents engage in discussions with facilitators and persons of trust to reach a decision. Documentation constitutes the focus of professionals, who endorse brief recommendations for procedures in case of emergencies, supplemented by larger advance directives. Implementation hindrances include emotional barriers of stakeholders, disagreements between parents and professionals and difficulties with emergency services. Discussion: timing should take into account parental readiness. The intervention should be repeated at regular intervals, considering emerging needs and increasing awareness of families over time. Involving children and adolescents in advance care planning remains a challenge. Conclusion: A paediatric advance care planning intervention should take into account potential pitfalls and barriers including issues related to timing, potential conflicts between parents and professionals, ambiguity towards written advance directives, the role of non-medical carers for paediatric advance care planning implementation, the need to involve the child and the necessity of an iterative process

Uptake and Transfer of Polyamide Microplastics in a Freshwater Mesocosm Study

Steadily increasing inputs of microplastics pose a growing threat to aquatic fauna, but laboratory studies potentially lack realism to properly investigate its effects on populations and ecosystems. Our study investigates the trophic and ontogenetic transfer of microplastics in a near-natural exposure scenario. The controlled outdoor freshwater mesocosms were exposed to polyamide (PA) 5–50 µm in size in concentrations of 15 and 150 mg L−1 and a control without microplastic addition. To verify the uptake of particles via the food chain, larvae and imagines of the midges Chaoborus crystallinus and C. obscuripes were examined, which feed on zooplankton during their larval stage. Larvae were captured after 117 days and imagines were caught in emergence traps that were emptied weekly. To detect the microparticles within the organisms, 200 larvae and 100 imagines per application were macerated and treated with fluorescent dye before investigation under a fluorescent microscope. We could detect up to 12 PA particles per individual larvae, while nearly no plastic was found in the imagines. This shows that, while Chaoborus sp. takes up microplastics via predation, most of the pollutant is egested through regurgitation and remains in the water, where it can further accumulate and potentially harm other organisms

What Program Directors Think IV : Results of the 2017 Annual Survey of the Association of Program Directors in Radiology

RATIONALE AND OBJECTIVES: The Association of Program Directors in Radiology (APDR) regularly surveys its members to gather information regarding a broad range of topics related to radiology residency. The survey results provide insight into the opinions of residency program leadership across the country. MATERIALS AND METHODS: This is an observational cross-sectional study using a web-based survey posed to the APDR membership in the fall of 2017. The final survey consisted of 53 items, 48 multiple choice questions and five write-in comments. An invitation to complete the survey was sent to all 319 active APDR members. RESULTS: Deidentified responses were collected electronically, tallied utilizing Qualtrics software, and aggregated for the purposes of analysis and reporting at the 66th annual meeting of the Association of University Radiologists. The response rate was 36%. CONCLUSION: Over the past 16 years, more PDs have assistant and APDs to administer growing residency programs, but the time allocation for these APDs has come from the PD\u27s protected time. An overwhelming majority of PDs consider independent call beneficial to residents and most think a call assistant is desirable. The vast majority of PDs support a unified fellowship match and allow resident moonlighting. Most fourth year residents are actively or moderately involved in clinical work and teaching. The majority of PDs have lost or expect to lose DR training positions to the new IR/DR programs. In a competitive match, PDs do not rely on residency interviews in their selection process

What program directors think IV : Results of the 2017 Annual Survey of the Association of Program Directors in Radiology

RATIONALE AND OBJECTIVES: The Association of Program Directors in Radiology (APDR) regularly surveys its members to gather information regarding a broad range of topics related to radiology residency. The survey results provide insight into the opinions of residency program leadership across the country. MATERIALS AND METHODS: This is an observational cross-sectional study using a web-based survey posed to the APDR membership in the fall of 2017. The final survey consisted of 53 items, 48 multiple choice questions and five write-in comments. An invitation to complete the survey was sent to all 319 active APDR members. RESULTS: Deidentified responses were collected electronically, tallied utilizing Qualtrics software, and aggregated for the purposes of analysis and reporting at the 66th annual meeting of the Association of University Radiologists. The response rate was 36%. CONCLUSION: Over the past 16 years, more PDs have assistant and APDs to administer growing residency programs, but the time allocation for these APDs has come from the PD\u27s protected time. An overwhelming majority of PDs consider independent call beneficial to residents and most think a call assistant is desirable. The vast majority of PDs support a unified fellowship match and allow resident moonlighting. Most fourth year residents are actively or moderately involved in clinical work and teaching. The majority of PDs have lost or expect to lose DR training positions to the new IR/DR programs. In a competitive match, PDs do not rely on residency interviews in their selection process