An Ultrasonic Adaptive Beamforming Method and Its Application for Trans-Skull Imaging of Certain Types of Head Injuries; Part II: Reception Mode and Adaptive Imaging.

OBJECTIVE: Background theory and a new algorithm for single-point adaptive focusing in transmission mode through ultrasonic barriers via one-dimensional phased arrays were reported in part I. In this paper the algorithm is further extended and implemented into a full adaptive beamforming process, including complete transmission and reception modes. METHODS: Corrected time delay patterns, adapted to the local acoustical and geometrical properties of the barrier, are calculated and applied in both modes. Further, an adaptive imaging process is also developed that implements the proposed beamforming process for two-dimensional imaging through randomly shaped multilayered phase-aberrating structures. The method is optimized for the case of human skull as the ultrasound barrier and its application for transcranial imaging is discussed. RESULTS: Laboratory results of adaptive imaging through realistic skull-mimicking phantoms are presented. The algorithms are implemented on a 64-channel ultrasound open-source phased array platform controlling a standard 128-element biomedical phased array. Irregularly shaped reflectors with characteristic dimensions of the order of ∼0.5 mm to ∼4.5 mm were used as targets behind the skull phantoms in our experiments. Minimum and maximum distortional target displacements of 2.2 mm and 25.3 mm (in 12 cm depth) were observed in sonograms when uncompensated time delays were used. By contrast, the positioning errors ranged from 0.0 to 0.9 mm when our algorithm was employed. CONCLUSION AND SIGNIFICANCE: The adaptive imaging results demonstrate strong potential of the proposed technique for diagnostic imaging of acoustically reflective head injuries directly through intact human skull.

Influence of Magnetostriction Induced by the Periodic Permanent Magnet Electromagnetic Acoustic Transducer (PPM EMAT) on Steel.

The periodic permanent magnet electromagnetic acoustic transducer (PPM EMAT) is a sensor that can generate and receive shear horizontal (SH) waves without direct contact with the inspected medium using the Lorentz mechanism. However, the PPM EMAT experiences high signal variance on ferromagnetic steel under specific conditions, such as a change in signal amplitude when the sensor is moved in the direction of SH wave propagation. Magnetostriction effects are hypothesized to be the cause of these anomalous behaviors; the objective of this paper is to determine the relative strengths of the magnetostriction and Lorentz wave generation mechanisms for this type of EMAT on steel. This goal is accomplished through the use of a second EMAT, which induces only magnetostriction (MS-EMAT), to calibrate a novel semi-empirical magnetostriction model. It is found that magnetostriction effects reduce the amplitude of the SH wave generated by this particular PPM EMAT transmitter by an average of 29% over a range of input currents. It is also determined that magnetostriction is significant only in the investigated PPM EMAT transmitter, not the receiver. In terms of practical application, it is shown that the MS-EMAT is less sensitive to changes in the static and dynamic fields than PPM EMATs at specific operating points; this makes the MS-EMAT a viable alternative for nondestructive evaluation despite lower amplitudes.

Spectral Shift Originating from Non-linear Ultrasonic Wave Propagation and Its Effect on Imaging Resolution.

An amplitude-dependent downshift in the fundamental wave spectrum of a propagating ultrasonic pulse caused by non-linear wave propagation is described. The effects of non-linearity and the associated downshift on spatial resolution are also studied. The amounts of downshift and spatial resolution are extracted from the numerically simulated beam profile based on the KZK equation. Results for a 25-MHz transducer reveal that non-linear effects can lead to 58% additional downshift in the centre frequency of a pulse compared with a linear case with downshift caused only by attenuation. This additional downshift causes about 50% degradation in axial resolution. However, as the beam becomes narrower from the non-linear effects, the overall effect of non-linearity still leads to improved lateral resolution (≤26%). Therefore, as non-linearity increases with wave pressure, it is concluded that the increase in source pressure improves lateral resolution and degrades axial resolution.

Guiding principles for rewilding.

There has been much recent interest in the concept of rewilding as a tool for nature conservation, but also confusion over the idea, which has limited its utility. We developed a unifying definition and 10 guiding principles for rewilding through a survey of 59 rewilding experts, a summary of key organizations' rewilding visions, and workshops involving over 100 participants from around the world. The guiding principles convey that rewilding exits on a continuum of scale, connectivity, and level of human influence and aims to restore ecosystem structure and functions to achieve a self-sustaining autonomous nature. These principles clarify the concept of rewilding and improve its effectiveness as a tool to achieve global conservation targets, including those of the UN Decade on Ecosystem Restoration and post-2020 Global Biodiversity Framework. Finally, we suggest differences in rewilding perspectives lie largely in the extent to which it is seen as achievable and in specific interventions. An understanding of the context of rewilding projects is the key to success, and careful site-specific interpretations will help achieve the aims of rewilding.

Recientemente ha habido mucho interés por el concepto de retorno a la vida silvestre como herramienta para la conservación de la naturaleza, pero también ha habido confusión por la idea que ha limitado su utilidad. Desarrollamos una definición unificadora y diez principios básicos para el retorno a la vida silvestre por medio de encuestas a 59 expertos en retorno a la vida silvestre, un resumen de las visiones de las organizaciones más importantes para el retorno a la vida silvestre y talleres que involucraron a más de 100 participantes de todo el mundo. Los principios básicos transmiten que el retorno a la vida silvestre existe en un continuo de escala, conectividad y nivel de influencia humana y que su objetivo es restaurar la estructura y las funciones del ecosistema para lograr una naturaleza autónoma autosustentable. Estos principios aclaran el concepto del retorno a la vida silvestre e incrementan su efectividad como herramienta para lograr los objetivos mundiales de conservación, incluyendo aquellos de la Década de la ONU para la Restauración de Ecosistemas y el Marco de Trabajo de la Biodiversidad Global post 2020. Finalmente, sugerimos que las diferencias en las perspectivas del retorno a la vida silvestre yacen principalmente en el grado al que es visto como factible y en intervenciones específicas. Un entendimiento del contexto de los proyectos de retorno a la vida silvestre es importante para el éxito, y las interpretaciones específicas de sitio ayudarán a lograr las metas del retorno a la vida silvestre. Principios Básicos para el Retorno a la Vida Silvestre.

Determination of the Ultrasonic Non-linearity Parameter B/A versus Frequency for Water.

For tissue characterization, it is desirable to determine B/A using high-frequency transducers. Moreover, an accurate estimate of B/A at elevated frequencies (or at least the assumption of frequency independence of B/A) is required to evaluate the safety of high-frequency systems. However, common finite-amplitude approaches become increasingly inaccurate at high frequencies. In this article, a practical variation of the finite-amplitude method is proposed which combines experiments with numerical simulations of the Khokhlov-Zabolotskaya-Kuznetsov equation and can be used at elevated frequencies. The results at low frequencies show that the proposed approach is accurate with lower uncertainties compared with the finite-amplitude method because it avoids assumptions and approximations. The measured values of B/A versus frequency for water at 2.25-20 MHz show that there is no statistically significant variation in B/A values with frequency, and therefore the assumption of frequency independence of B/A is realistic.

Long-term surveys of age structure in 13 ungulate and one ostrich species in the Serengeti, 1926-2018.

The Serengeti ecosystem spans an extensive network of protected areas in Tanzania, eastern Africa, and a UNESCO Wold Heritage Site. It is home to some of the largest animal migrations on the planet. Here, we describe a dataset consisting of the sample counts of three age classes (infant, juvenile and adult) of 13 ungulate and one ostrich species. Sample counts were tallied visually from the ground, or, in some instances, aerial photographs, during a period extending from 1926 to 2018. Observed animals were assigned to age classes based on specific criteria for each species. For nine of the 14 species of this dataset, the number of sampling years is over 30. This resulted in a total of 533 different records of count across age classes. By computing age-class ratios, these data can be used to measure long-term recruitment success at different ages of the tallied species. In particular, the temporal extent of these data allows comparison of patterns to other long-term processes, such as the El Niño-Southern Oscillation (ENSO).

Sensors for Ultrasonic Nondestructive Testing (NDT) in Harsh Environments.

In this special issue of Sensors, seven peer-reviewed manuscripts appear on the topic of ultrasonic transducer design and operation in harsh environments: elevated temperature, high gamma and neutron fields, or the presence of chemically aggressive species. Motivations for these research and development projects are strongly focused on nuclear power plant inspections (particularly liquid-sodium cooled reactors), and nondestructive testing of high-temperature piping installations. It is anticipated that we may eventually see extensive use of permanently mounted robust transducers for in-service monitoring of petrochemical plants and power generations stations; quality control in manufacturing plants; and primary and secondary process monitoring in the fabrication of engineering materials.

Long-term monitoring of Serengeti bird species occurrence, abundance, and habitat.

The Serengeti ecosystem contains one of the most diverse bird assemblages in Africa. We present here a data set consisting of abundances of bird species in different habitats of the Serengeti ecosystem over a 87-yr time frame. This data set comprises 66,643 georeferenced occurrences for 568 species from 1929 to 2017. Most records contain feeding location, food source, distribution status, and observation locality. The records originate from three different but complementary methodologies: points, sites, and transects. The point method (bird species records 1929-2017) is based on ad hoc observations and includes rare species or those in special habitats. These points came from published records as well from the research program of A. R. E. Sinclair and colleagues. The site method (1966-2017) is based on structured observations at sites selected to represent specific habitats, and replicated within habitats and over time. At each site, birds were recorded by sight and sound over a radius of 50 m for 10 min. The transect method (1997-2011) is based on road transects covering different areas of the ecosystem. Road transects were traversed using a vehicle with observers travelling at 30 km/h. Bird species were those easily seen from a vehicle out to 50 m either side. As most transects were traversed multiple times, this method provides information on temporal change in abundance for a select set of species. No copyright restrictions apply to the use of this data set other than citing this publication.

Dry Coupling of Ultrasonic Transducer Components for High Temperature Applications.

The viability for dry coupling of piezoelectric ultrasonic transducer components was investigated, using a thin foil of annealed silver as a filler material/coupling agent at each component interface. Criteria used for room temperature evaluation were centered on signal-to-noise ratio (SNR) and echo bandwidth, for a Li-Nb based transducer operating in pulse-echo mode. A normal clamping stress of only 25 MPa, applied repeatedly over three loading cycles on a precisely-aligned transducer stack, was sufficient to yield backwall echoes with a SNR greater than 25 dB, and a 3 dB bandwidth of approximately 65%. This compares to a SNR of 32 dB and a 3 dB bandwidth of 65%, achievable when all transducer interfaces were coupled with ultrasonic gel. The respective roles of a soft filler material, alignment of transducer components, cyclic clamping, component roughness, and component flatness were evaluated in achieving this high efficiency dry coupling, with transducer clamping forces far lower than previously reported. Preliminary high temperature tests indicate that this coupling method is suitable for high temperature and achieves signal quality comparable to that at room temperature with ultrasonic gel.

Non-linear Wave Propagation and Safety Standards for Diagnostic Ultrasound Devices.

Safety standards for clinical diagnostic ultrasonic devices were developed for use in relatively low-frequency systems (1-10 MHz), under the assumption that non-linear effects would be negligible. This article reviews ways in which neglecting non-linear wave propagation affects the measurements and calculations required to comply with safety standards and U.S. Food and Drug Administration guidance that recognizes these standards. An attempt is made to evaluate whether ignoring non-linear effects could result in significant error in the exposure quantities defined in these standards at either low or high frequencies, based on published literature. This article maintains that although non-linear effects have been considered in some parts of safety standards related to hydrophone requirements, the coverage is inadequate, especially for modern equipment with high working frequencies. A new approach is required to assess the magnitude of thermal heating for recently developed high-frequency systems to incorporate non-linear effects. In contrast, the current approach for evaluating the risk of cavitation can be used after appropriate modifications.

'Single-checked' Patient Group Directions during initial nurse assessment within paediatric emergency departments of the UK and Ireland.

OBJECTIVE: Double checking medications at initial assessment within paediatric emergency departments (EDs) has the potential to delay patient flow, and doubt has been cast on the efficacy of double checking in all but high-risk medications. We aimed to benchmark current practice for the use of Patient Group Direction (PGD) medications at initial assessment in EDs within the Paediatric Emergency Research UK and Ireland (PERUKI) network, with a focus on the use of 'single-checker' PGDs. METHODS: Online survey was distributed to the research representative at each PERUKI site. The survey was open for 5 weeks (from March 2015 to April 2015) and was completed by any appropriate clinician within the site. RESULTS: The response rate was 84% (36/43 EDs). From these, 22 out of 36 (61%) EDs were using single-checker PGDs. The commonest single-checked medications in use were paracetamol and ibuprofen for pain. Among PERUKI sites, 21.9% of EDs reported drug errors related to standard (double-checked) PGDs, whereas 13.6% of those with single-checked PGDs reported drug errors (Fisher's exact test with significance level of 0.05, P=0.501). The commonest errors reported were duplicated dose, incorrect weight, incorrect volume drawn up, contraindication missed. CONCLUSION: Single-checker PGDs are currently in use in nearly two-thirds of PERUKI sites. No evidence of increased medication errors was reported with this practice; however, more detailed studies are required to support this finding and to inform best practice.

Future enhanced clinical role of pharmacists in Emergency Departments in England: multi-site observational evaluation.

Background There are concerns about maintaining appropriate clinical staffing levels in Emergency Departments. Pharmacists may be one possible solution. Objective To determine if Emergency Department attendees could be clinically managed by pharmacists with or without advanced clinical practice training. Setting Prospective 49 site cross-sectional observational study of patients attending Emergency Departments in England. Method Pharmacist data collectors identified patient attendance at their Emergency Department, recorded anonymized details of 400 cases and categorized each into one of four possible options: cases which could be managed by a community pharmacist; could be managed by a hospital pharmacist independent prescriber; could be managed by a hospital pharmacist independent prescriber with additional clinical training; or medical team only (unsuitable for pharmacists to manage). Impact indices sensitive to both workload and proportion of pharmacist manageable cases were calculated for each clinical group. Main outcome measure Proportion of cases which could be managed by a pharmacist. Results 18,613 cases were observed from 49 sites. 726 (3.9%) of cases were judged suitable for clinical management by community pharmacists, 719 (3.9%) by pharmacist prescribers, 5202 (27.9%) by pharmacist prescribers with further training, and 11,966 (64.3%) for medical team only. Impact Indices of the most frequent clinical groupings were general medicine (13.18) and orthopaedics (9.69). Conclusion The proportion of Emergency Department cases that could potentially be managed by a pharmacist was 36%. Greatest potential for pharmacist management was in general medicine and orthopaedics (usually minor trauma). Findings support the case for extending the clinical role of pharmacists.

Investigating the cost and efficiency of incident reporting in a specialist paediatric NHS hospital and impact on patient safety.

OBJECTIVES: The aim of this study was to investigate the incident reporting process (IR1s), to calculate the costs of reporting incidents in this context and to gain an indication of how economic the process was and whether it could be improved to yield better outcomes. METHODS: A retrospective analysis of a sample, 10.47% (n=150) selected from 1432 medication incident report summaries, generated at Birmingham Children's Hospital, a specialist tertiary referral paediatric centre, during 2014 and collated through the national Datix incident reporting system software was analysed and the associated staff time required to complete each step of the incident reporting process was costed. The staff costs for various grades of staff were averaged across the staff actually involved, using data calculated by the Personal Social Services Research Unit. RESULTS: The analysis showed that the incident reporting process involved 262 staff on 2942 occasions (19.16 staff episodes per incident form completed) at a cost of £337.16 per incident form completed. CONCLUSIONS: The study showed that the incident reporting system was a labour intensive process. The numbers of staff involved in the process particularly as a result of the email distribution activity did appear to have room for efficiencies. However, it proved to be relatively inexpensive from a cost perspective. With redesign, arguably the emphasis could be moved away from the recording process to learning in order to gain improved patient safety outcomes.

A telephone survey to determine the experiences of children and their parents/carers, following the initiation of a new medicine.

OBJECTIVE: To determine what issues are experienced during the first few weeks of therapy by patients, and their parents/carers, when a child/young person has been prescribed a new medicine. METHOD: One hundred patients aged ≤18 years of age prescribed a new medicine for ≥6 weeks were recruited from a single UK National Health Service specialist paediatric hospital outpatient pharmacy. Six weeks after the first dispensing of their new medicine the patient or their parent/carer received telephone follow-up by a researcher and verbally completed a questionnaire containing both open and closed questions. Patient or parent/carer experiences were identified and analysed using thematic analysis and descriptive statistics. RESULTS: Eighty-six participants were available for telephone follow-up. Six (7%) had not started their medicine. Paediatric patients and their parents/carers experienced a range of issues during the first few weeks after starting a new medicine. These included additional concerns/questions (24/80, 30%), administration issues (21/80, 26.3%), adverse effects (29/80, 36.3%) and obtaining repeat supplies (12/80, 15%). The Morisky Medication Adherence Scale indicated that 34/78 (43.6%) participants had a high adherence rating, 35/78 (44.9%) medium and 9/78 (11.5%) a low rating. CONCLUSIONS: Paediatric patients and their parents/carers experience a range of issues during the first few weeks after starting a new medicine. Further research is required to determine the type of interventions that may further support medicines use in this group of patients.

THE POTENTIAL FOR PHARMACISTS TO MANAGE CHILDREN ATTENDING EMERGENCY DEPARTMENTS.

AIM: There have been concerns about maintaining appropriate clinical staff levels in Emergency Departments in England.1 The aim of this study was to determine if Emergency Department attendees aged from 0-16 years could be managed by community pharmacists or hospital independent prescriber pharmacists with or without further advanced clinical practice training. METHOD: A prospective, 48 site, cross-sectional, observational study of patients attending Emergency Departments (ED) in England, UK was conducted. Pharmacists at each site collected up to 400 admissions and paediatric patients were included in the data collection. The pharmacist independent prescribers (one for each site) were asked to identify patient attendance at their Emergency Department, record anonymised details of the cases-age, weight, presenting complaint, clinical grouping (e.g. medicine, orthopaedics), and categorise each presentation into one of four possible categories: CP, Community Pharmacist, cases which could be managed by a community pharmacist outside an ED setting; IP-cases that could be managed at ED by a hospital pharmacist with independent prescriber status; IPT, Independent Prescriber Pharmacist with additional training-cases which could be managed at ED by a hospital pharmacist independent prescriber with additional clinical training; and MT, Medical Team only-cases that were unsuitable for the pharmacist to manage. An Impact Index was calculated for the two most frequent clinical groupings using the formula: Impact index=percentage of the total workload of the clinical grouping multiplied by the percentage ability of pharmacists to manage that clinical group. RESULTS: 1623 out of 18,229 (9%) attendees, from 45 of the 48 sites, were children aged from 0 to 16 years of age (median 8 yrs, range 0-16), 749 were female and 874 were male. Of the 1623 admissions, 9% of the cases were judged to be suitable for clinical management by a community pharmacist (CP), 4% suitable for a hospital pharmacist independent prescriber (IP), 32% suitable for a hospital independent pharmacist prescriber with additional training (IPT); and the remaining 55% were only suitable for the Medical Team (MT). The most frequent clinical groups and impact index for the attendees were General Medicine=10.78 and orthopaedics=10.60. CONCLUSION: Paediatric patients attending Emergency Departments were judged by pharmacists to be suitable for management outside a hospital setting in approximately 1 in 11 cases, and by hospital independent prescriber pharmacists in 4 in 10 cases. With further training, it was found that the total proportion of cases that could be managed by a pharmacist was 45%. The greatest impact for pharmacist management occurs in general medicine and orthopaedics.

MEDICATION REVIEW OF CHILDREN ON LONG TERM MEDICATIONS: A REVIEW OF THE LITERATURE.

INTRODUCTION: Children on long term medication may be under the care of more than one medical team including the patients GP. Children on chronic medication should be supported and their medications reviewed, especially in cases of polypharmacy. Medicines Use Reviews (MURs) were introduced into the pharmacy contract in 2005. The service was designed for community pharmacists to review patients on long term medication. The service specified that MURs were done on patients who can give consent and cannot be conducted with a parent or carer. Hence the service may be inaccessible to paediatric patients. This review aims to find studies that identify medication review services in primary care that cater for children on long term medication. METHODS: A literature search was conducted on 6th June 2015 using the keywords, ("Medication" or "review" or "Medication Review" or "Medicines use review" or "Medication use review" or "New Medicine Service") AND ("community pharmacy" OR "community pharmacist" OR "primary care" OR "General practice" OR "GP" OR "community paediatrician" OR "community pediatrician" OR "community nurse"). Bibliographic databases used were AMED, British Nursing Index, CINAHL, EMBASE, HMIC, MEDLINE, PsycINFO and Health Business Elite. Inclusion criteria were: paediatric specific medication review in primary care, for example by either a GP, community paediatrician, community nurse or community pharmacist. Exclusion criteria were studies of medication review in adults/unclear patient age and secondary care medication reviews. RESULTS: From the 417 articles, 6 relevant articles were found after abstract and full text review. 235 articles were excluded after title and abstract review (11 did not have full text in English); 96 were adult or non-age specified medication review/MUR/New Medicine Service studies; 63 referred to observational, evaluative studies of interventions in adults; 6 were non-paediatric specific systematic reviews and 17 were protocols, commentaries, news, and letters.The 6 relevant articles consisted of 1 literature review (published 2004), 3 research articles and 1 published protocol. The literature review[1] recommended that children's long term medication should be reviewed. The published protocol stated that the NMS minimum age for inclusion in the trial was for children aged over 13 years of age. The four studies were related to psychiatrists reviewing paediatric mental health patients in the USA, a pharmacist using Drug Related Problem to review patients in GP practices in Australia, a UK study based on an information prescription concept by providing children dispensed medications in community pharmacy with signposting them to health information and one GP practice based study observing pharmaceutical care issues in children and adults. CONCLUSION: The results show that there are currently no known studies on medication use reviews specific to children, whereas in adults, published evaluations are available. The terms of the MUR policy restrict children's access to the service and so more studies are necessary to determine whether children could benefit from such access.

Landscape-level movement patterns by lions in western Serengeti: comparing the influence of inter-specific competitors, habitat attributes and prey availability.

BACKGROUND: Where apex predators move on the landscape influences ecosystem structure and function and is therefore key to effective landscape-level management and species-specific conservation. However the factors underlying predator distribution patterns within functional ecosystems are poorly understood. Predator movement should be sensitive to the spatial patterns of inter-specific competitors, spatial variation in prey density, and landscape attributes that increase individual prey vulnerability. We investigated the relative role of these fundamental factors on seasonal resource utilization by a globally endangered apex carnivore, the African lion (Panthera leo) in Tanzania's Serengeti National Park. Lion space use was represented by novel landscape-level, modified utilization distributions (termed "localized density distributions") created from telemetry relocations of individual lions from multiple neighbouring prides. Spatial patterns of inter-specific competitors were similarly determined from telemetry re-locations of spotted hyenas (Crocuta crocuta), this system's primary competitor for lions; prey distribution was derived from 18 months of detailed census data; and remote sensing data was used to represent relevant habitat attributes. RESULTS: Lion space use was consistently influenced by landscape attributes that increase individual prey vulnerability to predation. Wet season activity, when available prey were scarce, was concentrated near embankments, which provide ambush opportunities, and dry season activity, when available prey were abundant, near remaining water sources where prey occurrence is predictable. Lion space use patterns were positively associated with areas of high prey biomass, but only in the prey abundant dry season. Finally, at the broad scale of this analysis, lion and hyena space use was positively correlated in the comparatively prey-rich dry season and unrelated in the wet season, suggesting lion movement was unconstrained by the spatial patterns of their main inter-specific competitors. CONCLUSIONS: The availability of potential prey and vulnerability of that prey to predation both motivate lion movement decisions, with their relative importance apparently mediated by overall prey abundance. With practical and theoretical implications, these results suggest that while top carnivores are consistently cognizant of how landscape features influence individual prey vulnerability, they also adopt a flexible approach to range use by adjusting spatial behaviour according to fluctuations in local prey abundance.

A New High-Temperature Ultrasonic Transducer for Continuous Inspection.

A novel design of piezoelectric ultrasonic transducer is introduced, suitable for operation at temperatures of up to 700 °C-800 °C. Lithium niobate single crystal is chosen as the piezoelectric element primarily due to the high Curie temperature of 1200 °C. A backing element based on a porous ceramic is designed for which the pore volume fraction and average pore diameter in the ceramic matrix can be controlled in the manufacturing process; this enables the acoustic impedance and attenuation to be selected to match their optimal values as predicted by a one-dimensional transducer model of the entire transducer. Porous zirconia is selected as the ceramic matrix material of the backing element to obtain an ultrasonic signal with center frequency of 2.7-3 MHz, and 3-dB bandwidth of 90%-95% at the targeted operating temperature. Acoustic coupling of the piezocrystal to the backing element and matching layer is investigated using commercially available high-temperature adhesives and brazing alloys. The performance of the transducer as a function of temperature is studied. Stable bonding and clear signals were obtained using an aluminum brazing alloy as the bonding agent.

An evaluation of the epidemiology of medication discrepancies and clinical significance of medicines reconciliation in children admitted to hospital.

AIMS: To determine the incidence of unintended medication discrepancies in paediatric patients at the time of hospital admission; evaluate the process of medicines reconciliation; assess the benefit of medicines reconciliation in preventing clinical harm. METHOD: A 5 month prospective multisite study. Pharmacists at four English hospitals conducted admission medicines reconciliation in children using a standardised data collection form. A discrepancy was defined as a difference between the patient's preadmission medication (PAM), compared with the initial admission medication orders written by the hospital doctor. The discrepancies were classified into intentional and unintentional discrepancies. The unintentional discrepancies were assessed for potential clinical harm by a team of healthcare professionals, which included doctors, pharmacists and nurses. RESULTS: Medicines reconciliation was conducted in 244 children admitted to hospital. 45% (109/244) of the children had at least one unintentional medication discrepancy between the PAM and admission medication order. The overall results indicated that 32% (78/244) of patients had at least one clinically significant unintentional medication discrepancy with potential to cause moderate 20% (50/244) or severe 11% (28/244) harm. No single source of information provided all the relevant details of a patient's medication history. Parents/carers provided the most accurate details of a patient's medication history in 81% of cases. CONCLUSIONS: This study demonstrates that in the absence of medicines reconciliation, children admitted to hospitals across England are at risk of harm from unintended medication discrepancies at the transition of care from the community to hospital. No single source of information provided a reliable medication history.