Thermal Modeling in Polymer Extrusion

In this paper we consider thermal effects of polymer flows through a cylindrical die. First, we derive a model for the oscillatory behavior of polymer flow in an extruder given a functional relation between the pressure and flow rate. A simple isothermal but temperature dependent model is constructed to find this relation. Unfortunately, the model is shown to be invalid in the physical regime of interest. We present several arguments to suggest that the isothermal assumption is reasonable but that a more detailed understanding of the small-scale molecular dynamics near the boundary may be required. Second, we show that a simplified model for thermoflow multiplicity in a cooled tube is inconsistent, when the stationary non-Newtonian flow is assumed to be incompressible without radial pressure gradients and without radial velocity. This inconsistency can be removed by allowing for weak compressibility effects in the down-steam area

Waste analysis plan for T Plant Complex

Washington Administration Code 173-303-300 requires that a waste analysis plan (WAP) be provided by a treatment, storage, and/or disposal (TSD) unit to confirm their knowledge about a dangerous and/or mixed waste to ensure that the waste is managed properly. The specific objectives of the WAP are as follows: Ensure safe management of waste during treatment and storage; Ensure that waste generated during operational activities is properly designated in accordance with regulatory requirements; Provide chemical and physical analysis of representative samples of the waste stored for characterization and/or verification before the waste is transferred to another TSD unit; Ensure compliance with land disposal restriction (LDR) requirements for treated waste; and Provide basis for work plans that describes waste analysis for development of new treatment technologies

Reliability of functional outcome measures in adults with neurofibromatosis 1

Objectives: To determine intra-rater and inter-rater reliability of functional outcome measures in adults with neurofibromatosis 1 (NF1) and to ascertain how closely objective and subjective measures align. Methods: Forty-nine ambulant adults with NF1 aged 16 years and over were included in this observational study. Median age 31 years (range 16-66), 29 females, 20 males. Participants were video-recorded or photographed performing four functional outcome measures. Four raters from the Neurofibromatosis centre multi-disciplinary team independently scored the measures to determine inter-rater reliability. One rater scored the measures a second time on a separate occasion to determine intra-rater reliability. The measures evaluated were the functional reach, timed up and go, ten metre walk and a modified nine-hole peg tests. Participants also completed a disease specific quality of life questionnaire (INF1-QOL). Results: Inter-rater reliability and intra-rater reliability scores (intra-class coefficient, ICC) were similar for each outcome measure. Excellent rater agreement (ICC r ≥ 0.9) was found for the functional reach, timed up and go and the 10 metre walk tests. Rater agreement was good for the modified 9-hole peg test; ICC r= 0.75 for intra-rater reliability and 0.76 for inter-rater reliability. The timed up and go and the 10 metre walk tests correlated highly with perceived mobility challenges in the quality of life questionnaire (INF1-QOL). Conclusions: The functional reach, timed up and go and 10 metre walk tests are potentially useful outcome measures for monitoring NF1 treatment and will be assessed for validity and reliability in future multi-centre studies

Coherent excitation of the singlet-triplet mixed 1s4f state of helium

In this paper, we present a detailed theoretical description for the coherent electron-impact excitation, the subsequent time evolution, and the cascading decay process of the singlet-triplet mixed 1s4f state of helium. The excitation amplitude and phase of each sublevel of this state are related to measurable coincidence intensities and polarizations of the emitted photons. It is found that the intensity and polarization of the emitted photons are time modulated due to the singlet and triplet mixing in the 1s4f state

Quality Assurance in Emergency Medicine - A Caribbean Perspective

Purpose – Emergency medicine is a new specialty in the Caribbean. With the development of specialist training over the past 20 years, the issues of quality assurance and governance have become more prominent. The purpose of this paper is to explore the successes and challenges of implementing systems of quality assurance in this unique environment, highlighting issues peculiar to the Caribbean setting. Design/methodology/approach – This paper is a review of current practice in the emergency departments (ED) of the four major teaching hospitals of the University of the West Indies. Information was gathered through interviews with key stakeholders (including the respective ED residency directors, senior residents and senior nursing and administrative staff), review of departmental protocols and guidelines and reviews of current published and unpublished literature. Findings – Examples of good practice were identified in all six components of the clinical governance framework (clinical audit, clinical effectiveness, research and development, openness, risk management and education and training). Challenges to implementation of quality management included an underdeveloped quality culture, inadequate data collection, poor incentives for improvement and high external pressures, including staff shortages, departmental crowding and lack of public empowerment. Originality/value – This is the first published work on clinical governance and quality assurance in emergency medicine in the Caribbean. This paper gives an insight into the unique opportunities and challenges in the area of quality management and clinical governance in the developing world, and suggests ways forward with regard to more effective implementation of quality initiatives in under-resourced jurisdictions

Interoceptive impairments do not lie at the heart of Autism or Alexithymia

Background: Quattrocki and Friston (2012) argued that abnormalities in interoception–the process of representing one’s internal physiological states–could lie at the heart of autism, because of the critical role interoception plays in the ontogeny of social-affective processes. This proposal drew criticism from proponents of the alexithymia hypothesis, who argue that social-affective and underlying interoceptive impairments are not a feature of autism per se, but of alexithymia (a condition characterised by difficulties describing and identifying one's own emotions), which commonly co-occurs with autism. Despite the importance of this debate for our understanding of ASD, and of the role of interoceptive impairments in psychopathology more generally, direct empirical evidence is scarce and inconsistent. Methods: Experiment 1 examined in a sample of 137 neurotypical individuals the association among autistic traits, alexithymia, and interoceptive accuracy on a standard heartbeat tracking measure of interoceptive accuracy. In Experiment 2, interoceptive accuracy was assessed in 46 adults with ASD (27 of whom had clinically-significant alexithymia) and 48 neurotypical adults. Results: Experiment 1 confirmed strong associations between autistic traits and alexithymia, but yielded no evidence to suggest that either was associated with interoceptive difficulties. Similarly, Experiment 2 provided no evidence for interoceptive impairments in autistic adults, irrespective of any co-occurring alexithymia. Bayesian analyses consistently supported the null hypothesis. Conclusions: The observations pose a significant challenge to notions that interoceptive impairments constitute a core feature of either ASD or alexithymia, at least as far as the direct perception of interoceptive signals is concerned. General scientific summary: This article suggests that impairments in interoception–the process of representing one’s internal physiological states–do not lie at the heart of either autism or alexithymia