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Numerical treatment of seismic accelerograms and of inelastic seismic structural responses using harmonic wavelets
The harmonic wavelet transform is employed to analyze various kinds of nonstationary signals common in aseismic design. The effectiveness of the harmonic wavelets for capturing the temporal evolution of the frequency content of strong ground motions is demonstrated. In this regard, a detailed study of important earthquake accelerograms is undertaken and smooth joint time-frequency spectra are provided for two near-field and two far-field records; inherent in this analysis is the concept of the mean instantaneous frequency. Furthermore, as a paradigm of usefulness for aseismic structural purposes, a similar analysis is conducted for the response of a 20-story steel frame benchmark building considering one of the four accelerograms scaled by appropriate factors as the excitation to simulate undamaged and severely damaged conditions for the structure. The resulting joint time-frequency representation of the response time histories captures the influence of nonlinearity on the variation of the effective natural frequencies of a structural system during the evolution of a seismic event. In this context, the potential of the harmonic wavelet transform as a detection tool for global structural damage is explored in conjunction with the concept of monitoring the mean instantaneous frequency of records of critical structural responses
Real Property
Covers cases on limited-access higway condemnation—compensation for loss of easement of access—measure of compensation and on adverse user—necessity of claim of right
Heart Attack Cases Under the Washington Workmen\u27s Compensation Act
The recent case of Windust v. Department of Labor and Industries brought an important change in Washington workmen\u27s compensation law with the overruling of a long-standing rule relating to recovery under workmen\u27s compensation for heart failure. The Windust case apparently means there can be recovery for heart failure resulting from strain only when the strain is unusual. It appears that if the worker is doing only a routine act there can be no recovery. Though the new rule is not definitively articulated at this point, this inquiry will attempt to assess what the Washington Supreme Court has done and indicate what it will do in the future
Variability in antifungal and antiviral use in hospitalized children
We analyzed antifungal and antiviral prescribing among high-risk children across freestanding children’s hospitals. Antifungal and antiviral days of therapy varied across hospitals. Benchmarking antifungal and antiviral use and developing antimicrobial stewardship strategies to optimize use of these high cost agents is needed.Infect Control Hosp Epidemiol2017;38:743–746</jats:p
Development and application of an antibiotic spectrum index for benchmarking antibiotic selection patterns across hospitals
Standard metrics for antimicrobial use consider volume but not spectrum of antimicrobial prescribing. We developed an antibiotic spectrum index (ASI) to classify commonly used antibiotics based on activity against important pathogens. The application of this index to hospital antibiotic use reveals how this tool enhances current antimicrobial stewardship metrics.Infect Control Hosp Epidemiol 2017;38:993–997</jats:p
Current state of antimicrobial stewardship in children’s hospital emergency departments
BACKGROUND Antimicrobial stewardship programs (ASPs) effectively optimize antibiotic use for inpatients; however, the extent of emergency department (ED) involvement in ASPs has not been described. OBJECTIVE To determine current ED involvement in children's hospital ASPs and to assess beliefs and preferred methods of implementation for ED-based ASPs. METHODS A cross-sectional survey of 37 children's hospitals participating in the Sharing Antimicrobial Resistance Practices collaboration was conducted. Surveys were distributed to ASP leaders and ED medical directors at each institution. Items assessed included beliefs regarding ED antibiotic prescribing, ED prescribing resources, ASP methods used in the ED such as clinical decision support and clinical care guidelines, ED participation in ASP activities, and preferred methods for ED-based ASP implementation. RESULTS A total of 36 ASP leaders (97.3%) and 32 ED directors (86.5%) responded; the overall response rate was 91.9%. Most ASP leaders (97.8%) and ED directors (93.7%) agreed that creation of ED-based ASPs was necessary. ED resources for antibiotic prescribing were obtained via the Internet or electronic health records (EHRs) for 29 hospitals (81.3%). The main ASP activities for the ED included production of antibiograms (77.8%) and creation of clinical care guidelines for pneumonia (83.3%). The ED was represented on 3 hospital ASP committees (8.3%). No hospital ASPs actively monitored outpatient ED prescribing. Most ASP leaders (77.8%) and ED directors (81.3%) preferred implementation of ED-based ASPs using clinical decision support integrated into the EHR. CONCLUSIONS Although ED involvement in ASPs is limited, both ASP and ED leaders believe that ED-based ASPs are necessary. Many children's hospitals have the capability to implement ED-based ASPs via the preferred method: EHR clinical decision support. Infect Control Hosp Epidemiol 2017;38:469-475
Exposure to extremely low frequency electromagnetic fields alters the behaviour, physiology and stress protein levels of desert locusts
Electromagnetic fields (EMFs) are present throughout the modern world and are derived from many man-made sources including overhead transmission lines. The risks of extremely-low frequency (ELF) electromagnetic fields are particularly poorly understood especially at high field strengths as they are rarely encountered at ground level. Flying insects, however, can approach close to high field strength transmission lines prompting the question as to how these high levels of exposure affect behaviour and physiology. Here we utilise the accessible nervous system of the locust to ask how exposure to high levels of ELF EMF impact at multiple levels. We show that exposure to ELF EMFs above 4 mT leads to reduced walking. Moreover, intracellular recordings from an identified motor neuron, the fast extensor tibiae motor neuron, show increased spike latency and a broadening of its spike in exposed animals. In addition, hind leg kick force, produced by stimulating the extensor tibiae muscle, was reduced following exposure, while stress-protein levels (Hsp70) increased. Together these results suggest that ELF EMF exposure has the capacity to cause dramatic effects from behaviour to physiology and protein expression, and this study lays the foundation to explore the ecological significance of these effects in other flying insects
The atmospheric impacts of monoterpene ozonolysis on global stabilised Criegee intermediate budgets and SO2 oxidation : experiment, theory and modelling
The gas-phase reaction of alkenes with ozone is known to produce stabilised
Criegee intermediates (SCIs). These biradical/zwitterionic species have the
potential to act as atmospheric oxidants for trace pollutants such as
SO<sub>2</sub>, enhancing the formation of sulfate aerosol with impacts on air
quality and health, radiative transfer and climate. However, the importance
of this chemistry is uncertain as a consequence of limited understanding of
the abundance and atmospheric fate of SCIs. In this work we apply
experimental, theoretical and numerical modelling methods to quantify the
atmospheric impacts, abundance and fate of the structurally diverse SCIs
derived from the ozonolysis of monoterpenes, the second most abundant group
of unsaturated hydrocarbons in the atmosphere. We have investigated the
removal of SO<sub>2</sub> by SCIs formed from the ozonolysis of three
atmospherically important monoterpenes (<i>α</i>-pinene, <i>β</i>-pinene and
limonene) in the presence of varying amounts of water vapour in large-scale
simulation chamber experiments that are representative of boundary layer conditions.
The SO<sub>2</sub> removal displays a clear dependence on water vapour
concentration, but this dependence is not linear across the range of
[H<sub>2</sub>O] explored. At low [H<sub>2</sub>O] a strong dependence of SO<sub>2</sub>
removal on [H<sub>2</sub>O] is observed, while at higher [H<sub>2</sub>O] this dependence
becomes much weaker. This is interpreted as being caused by the production of
a variety of structurally (and hence chemically) different SCIs in each of the
systems studied, which displayed different rates of reaction with water and
of unimolecular rearrangement or decomposition. The determined rate constants,
<i>k</i>(SCI+H<sub>2</sub>O), for those SCIs that react primarily with H<sub>2</sub>O range
from 4 to 310  ×  10<sup>−15</sup> cm<sup>3</sup> s<sup>−1</sup>. For those SCIs that
predominantly react unimolecularly, determined rates range from
130 to 240 s<sup>−1</sup>. These values are in line with previous results for the
(analogous) stereo-specific SCI system of <i>syn</i>-/<i>anti</i>-CH<sub>3</sub>CHOO. The experimental results are
interpreted through theoretical studies of the SCI unimolecular reactions and
bimolecular reactions with H<sub>2</sub>O, characterised for <i>α</i>-pinene and
<i>β</i>-pinene at the M06-2X/aug-cc-pVTZ level of theory. The theoretically
derived rates agree with the experimental results within the uncertainties. A
global modelling study, applying the experimental results within the
GEOS-Chem chemical transport model, suggests that > 97 % of
the total monoterpene-derived global SCI burden is comprised of SCIs with a
structure that determines that they react slowly with water and that their atmospheric
fate is dominated by unimolecular reactions. Seasonally averaged boundary
layer concentrations of monoterpene-derived SCIs reach up to
1.4  ×  10<sup>4</sup> cm<sup>−3</sup> in regions of elevated monoterpene
emissions in the tropics. Reactions of monoterpene-derived SCIs with SO<sub>2</sub>
account for < 1 % globally but may account for up to 60 % of
the gas-phase SO<sub>2</sub> removal over areas of tropical forests, with
significant localised impacts on the formation of sulfate aerosol and hence
the lifetime and distribution of SO<sub>2</sub>
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