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

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

Further investigations into the single metal deposition (SMD II) technique for the detection of latent fingermarks

Single metal deposition (SMD II), a recently proposed method for the development of latent fingermarks, was investigated by systematically altering aspects of the procedure to assess their effect on the level of development and contrast achieved. Gold nanoparticle size, temperature of the deposition solution bath, and orbital shaking during detection were shown to affect the levels of development and contrast obtained. Gold nanoparticles of diameter 15–21 nm were found to be most effective for satisfactory visualisation of latent fingermarks, while solutions that were applied at room temperature were found to adequately balance the ratio between the contrast of the fingermark ridge detail and the level of background staining achieved. Finally, optimum levels of development and contrast were obtained through constant agitation of both solution baths at approximately 50 RPM throughout the submersion time. SMD II was also tested on a large variety of substrate types and shown to be effective on a range of porous, non-porous, and semi-porous surfaces; however, the detection quality can be significantly influenced by the substrate nature. This resulted in the production of dark grey, white, or gold coloured fingermarks on different surfaces, as well as reversed detection on certain types of plastic, similarly seen through the use of vacuum metal deposition. © 2016 Elsevier Ireland Lt

Application of Wavelet Theory in the Analysis of Earthquake Motions Recorded During the Kocaeli Earthquake, Turkey 1999

The Marmara region of Turkey was shaken by an earthquake with a magnitude of 7.4 and epicentre in Golcuk on August 17, 1999. Structural damage of various degrees occurred in the region. In this paper the strong motion data acquired from this earthquake at various locations are closely inspected using Fourier transform and a time-frequency technique using harmonic wavelets developed at Cambridge, Newland (1993). The advantage of harmonic wavelet analysis when dealing with non-stationary signals like earthquakes is that one can plot the signal in a time-frequency space enabling the energy distribution in the signa4 to be observed. An introduction to wavelet theory will be presented along with various methods for applying this theory to earthquake acceleration signals for analysis. Conclusions are drawn based on the application of wavelet method to the Kocaeli Earthquake strong motion data. These data is analyzed for four locations with increasing distance from the epicentre. The energy of a signal can be broken into its constituents at different frequency bands and time locations via wavelet analysis, giving insight into the localised portions of the signal. The magnitude of accelerations decreases as one moves away from the epicentre. Wavelet transform allows us to see the discontinuities within the signal and zoom in for closer inspection. Using the wavelets, it was observed that in the Kocaeli earthquake ground motions, acceleration with same frequency occurred at different time instants. This could not have been observed by traditional DFFT methods

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

Level Crossing Analysis of Growing surfaces

We investigate the average frequency of positive slope $\nu_{\alpha}^{+}$, crossing the height $\alpha = h- \bar h$ in the surface growing processes. The exact level crossing analysis of the random deposition model and the Kardar-Parisi-Zhang equation in the strong coupling limit before creation of singularities are given.Comment: 5 pages, two column, latex, three figure