1,023 research outputs found

    Use of International Classification of Diseases, Ninth Revision Codes for Obesity: Trends in the United States from an Electronic Health Record-Derived Database.

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    Obesity is a potentially modifiable risk factor for many diseases, and a better understanding of its impact on health care utilization, costs, and medical outcomes is needed. The ability to accurately evaluate obesity outcomes depends on a correct identification of the population with obesity. The primary objective of this study was to determine the prevalence and accuracy of International Classification of Diseases, Ninth Revision (ICD-9) coding for overweight and obesity within a US primary care electronic health record (EHR) database compared against actual body mass index (BMI) values from recorded clinical patient data; characteristics of patients with obesity who did or did not receive ICD-9 codes for overweight/obesity also were evaluated. The study sample included 5,512,285 patients in the database with any BMI value recorded between January 1, 2014, and June 30, 2014. Based on BMI, 74.6% of patients were categorized as being overweight or obese, but only 15.1% of patients had relevant ICD-9 codes. ICD-9 coding prevalence increased with increasing BMI category. Among patients with obesity (BMI ≥30 kg/m2), those coded for obesity were younger, more often female, and had a greater comorbidity burden than those not coded; hypertension, dyslipidemia, type 2 diabetes mellitus, and gastroesophageal reflux disease were the most common comorbidities. KEY FINDINGS: US outpatients with overweight or obesity are not being reliably coded, making ICD-9 codes undependable sources for determining obesity prevalence and outcomes. BMI data available within EHR databases offer a more accurate and objective means of classifying overweight/obese status

    Building a Standard Measurement Platform

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    Network management is achieved through a large number of disparate solutions for different technologies and parts of the end-to-end network. Gaining an overall view, and especially predicting the impact on a service user, is difficult. Recently, a number of proprietary platforms have emerged to conduct end-to-end testing from user premises; however, these are limited in scale, interoperability, and the ability to compare like-for-like results. In this article we show that these platforms share similar architectures and can benefit from the standardization of key interfaces, test definitions, information model, and protocols. We take the SamKnows platform as a use case and propose an evolution from its current proprietary protocols to standardized protocols and tests. In particular, we propose to use extensions of the IETF's IPFIX and NETCONF/YANG in the platform. Standardization will allow measurement capabilities to be included on many more network elements and user devices, providing a much more comprehensive view of user experience and enabling problems and performance bottlenecks to be identified and addressed.Publicad

    Targets and measures : challenges associated with reporting low sea lice levels on Atlantic salmon farms

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    A popular framing of Goodhart's Law states, "When a measure become a target, it ceases to be a good measure". The extent to which this may be the case in the reporting of sea louse infestation on salmon farms is explored here. Due to the importance of controlling sea louse infestation on salmon farms, monitoring programmes are active in most salmon producing regions and, in many, a maximum allowable sea louse level is specified. Using publicly accessible data from Norway and BC, Canada, this study investigated the extent to which the framing of these programmes, in particular the specification of low threshold levels, may be affecting the veracity of the reported sea louse infestation data. In BC, where the threshold level is set to 3 mobile Lepeophtheirus salmonis little evidence of anomalous patterns in the data and the overall proportion of females within the adult sea lice population is around 0.43. By contrast, in Norway where lower sea louse limits are in place (at either 0.5 or 0.2 adult female L. salmonis), there is evidence of unexpected and sharp reductions in the abundance of adult females reported around these threshold values. In addition, the average proportion of females is estimated to be only around 0.20 of the total adult L. salmonis population. The unexpected observations in the data were much more evident for farms in the southern areas of Norway and over the most recent years. These findings appear to support the case that the measurement of sea lice on salmon farms can be significantly influenced by targets (particularly those which are highly demanding), and that as such, researchers and fish health professionals should be aware of potential biases within these data. In addition, regulators should carefully consider the unintended consequences of setting certain sea louse thresholds and the ways in which the potential to effectively review data quality and accuracy may be impacted by the choice of sea louse stage(s) that are reported

    Improving the hydrolytic stability of aryl cyanate esters by examining the effects of extreme environments on polycyanurate copolymers

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    Three cyanate ester monomer or oligomer species: 2,2-bis(4-cyanatophenyl)propane 1, 1-1-bis(4-dicyanatophenyl)ethane 2, and the oligomeric phenolic cyanate 3, are blended in various ratios to form binary mixtures (18 in total), formulated with copper(II) acetylacetonate (200 ppm) in dodecylphenol (1 % w/v active copper suspension) and cured (3 Kmin-1 to 150 °C + 1 hour; 3 Kmin-1 to 200 °C + 3 hours) followed by a post cure (3 Kmin-1 to 260 °C + 1 hour). Cured copolymers were exposed to environments of elevated relative humidity (75 % RH) and parallel immersion testing in H2O, H2SO4 (10 %) and NaOH (10 %) at 25 °C for a period of up to 2 years and accelerated ageing in boiling water (14 days). Periodic measurements are made of moisture gain along with infrared spectra and compared with cured homopolymers. Changes in mass are recorded periodically throughout exposure, prior to destructive thermo-mechanical analyses. Dynamic mechanical thermal analysis data comparing neat and exposed blends demonstrate the detrimental effect of moisture ingress whilst data from thermogravimetric analysis demonstrate no change in degradation onset between neat and exposed materials. An optimised blend of 1:1 of monomer units 1 and 2 was found to absorb less moisture than blends of different stoichiometry or between other respective monomeric units, consequently limiting the deleterious effect of moisture ingress

    Investigation of structure property relationships in liquid processible, solvent free, thermally stable bismaleimide-triazine (BT) resins

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    Three cyanate ester monomer or oligomer species: 2,2-bis(4-cyanatophenyl)propane 1, 1-1-bis(4-cyanatophenyl)ethane (2), and the oligomeric phenolic cyanate (PrimasetTM PT30) (3), are blended in various ratios with bis(4-maleimidophenyl)methane, (4), to form binary and ternary mixtures (11 in total) and cured, in the absence of catalysts (3 K/min to 150 °C + 1 hour; 3 K/min to 200 °C + 3 hours), followed by a post cure (3 K/min to 260 °C + 1 hour). The use of liquid monomer, (2), offers the possibility of liquid processing in blends containing minority compositions of bismaleimide. Glycidylmethacrylate is explored as a reactive diluent (2.5-10 wt %) to linked interpenetrating network polymer structures comprising cyanate ester and bismaleimide components with glass transition temperatures of 267-275 ºC, depending on composition; the onset of thermo-oxidative degradation ranges from 386-397 ºC. When a binary blend of (2) and (3) (with the former in the minority) is co-cured with (4), an excellent balance of properties is achieved with liquid processing, a Tg greater than 400 C and onset of degradation of 425 ºC in static air. Kinetic analysis of DSC data using Ozawa and Kissinger methods yield activation energies of between 107- 112 kJ/mole for a binary blend of (1)90-(4)10, which is in good agreement with literature. Molecular dynamics simulation of the same blend in cured form gave a simulated glass transition temperature of 250 C that is in very close agreement with empirical DMTA data

    Surveying drifting icebergs and ice islands: Deterioration detection and mass estimation with aerial photogrammetry and laser scanning

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    Icebergs and ice islands (large, tabular icebergs) are challenging targets to survey due to their size, mobility, remote locations, and potentially difficult environmental conditions. Here, we assess the precision and utility of aerial photography surveying with structure-from-motion multi-view stereo photogrammetry processing (SfM) and vessel-based terrestrial laser scanning (TLS) for iceberg deterioration detection and mass estimation. For both techniques, we determine the minimum amount of change required to reliably resolve iceberg deterioration, the deterioration detection threshold (DDT), using triplicate surveys of two iceberg survey targets. We also calculate their relative uncertainties for iceberg mass estimation. The quality of deployed Global Positioning System (GPS) units that were used for drift correction and scale assignment was a major determinant of point cloud precision. When dual-frequency GPS receivers were deployed, DDT values of 2.5 and 0.40 m were calculated for the TLS and SfM point clouds, respectively. In contrast, values of 6.6 and 3.4 m were calculated when tracking beacons with lower-quality GPS were used. The SfM dataset was also more precise when used for iceberg mass estimation, and we recommend further development of this technique for iceberg-related end-uses

    Pure Stationary States of Open Quantum Systems

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    Using Liouville space and superoperator formalism we consider pure stationary states of open and dissipative quantum systems. We discuss stationary states of open quantum systems, which coincide with stationary states of closed quantum systems. Open quantum systems with pure stationary states of linear oscillator are suggested. We consider stationary states for the Lindblad equation. We discuss bifurcations of pure stationary states for open quantum systems which are quantum analogs of classical dynamical bifurcations.Comment: 7p., REVTeX
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