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Phytoremediation, as a bioremediation process in which plants are used to remove contaminants from an environment, has proved to be a practical and low-cost strategy for recovering mining-affected areas. This study aims to assess the potential for use in phytoremediation of two willow species, Salix viminalis and Salix dasyclados, by testing their potential for cleaning-up a range of soils with differing heavy metal concentrations: Pb (111, 141, 192 and 249 mg /kg), Zn (778.6, 1482, 2734 and 4411 mg/kg) and Cd (3.00, 5.03, 9.14 and 16.07 mg/kg). The extracted metals were preferentially translocated to the leaves with considerably higher concentrations and relative BAFs in the case of S. viminalis. The highest recorded Zn concentration of over 0.5% was found in the leaves of S. viminalis growing in soil 4. However, under the conditions of the experiments, S. dasyclados showed greater potential for use in phytoremediation, especially if coupled with use of biomass for energy production. An assessment of the suitability of willow species in this role, with regard to wider aspects involved, such as use of resultant biomass and/or waste management, revealed good potential. Willows are fast growing, grow vigorously from coppiced stumps and have extensive root systems. Therefore, their use in bioenergy production through pyrolysis or combustion, coupled with flue gas screening, is strongly advised.

The journal retracts the article “Phytoremediation of Heavy-Metals-Contaminated Soils: A Short-Term Trial Involving Two Willow Species from Gloucester WillowBank in the UK” [...]

Numerous permanent and temporary wetlands occur throughout the world’s drylands. Although characterised by diverse hydroperiods, these wetlands in drylands are typically hotspots of biological activity and productivity. The healthy functioning and possibly even existence of many wetlands in drylands, however, is threatened by desiccation resulting from a combination of climate change and human disturbance. Near Alcañiz in arid northeast Spain, three adjacent saladas (playas) with contrasting hydroperiods provide an opportunity to investigate how moisture availability affects their soil carbon (C) stocks, CO2 efflux, and microbial communities. Frequent inundation and/or near-permanent soil saturation supports the generation of organic C from a range of different sources. Soil inorganic C was greatest on the driest salada (3.8 %) compared to the wetter saladas (3.0 % and 2.1 %) owing to evaporative concentration and the reaction of CO2 with available Ca2+, Mg2+ and Na+ ions. CO2 efflux was greatest at intermediate moisture levels (142 mg CO2 m-2 hr-1), but the spatial and temporal variability in CO2 efflux on salada surfaces is very high, demonstrating the need for intensive sampling regimes to provide realistic estimates of their contribution to atmospheric CO2 exchanges. Different microbial community structures also characterise each salada. The saladas near Alcañiz, and many other similar features in northeast Spain, are renowned for their rare and threatened flora and fauna, yet their soil C cycle characteristics and soil microbial communities provide additional reasons to monitor the impacts of climate change and protect these vulnerable environments from further anthropogenic disturbances.

The 3 April 2017 MW 6.5, Moiyabana (Botswana) earthquake occurred in the continental interior of the African plate and in a seismogenic region previously considered as stable. We analyse the mainshock and aftershock sequence based on a local seismic network and local seismotectonic characteristics. The earthquake rupture geometry is constrained with more than 1,000 aftershocks recorded over a period of three months and from the InSAR analysis of Sentinel-1 images (ascending orbit). The mainshock (25.134 E, 22.565 S; depth 22 ± 3 km) was followed by more than 500 events of magnitude M ≥ 0.8 recorded in April 2017 including the largest aftershock (MW 4.6 on the 5 April 2017). Focal mechanism solutions of the mainshock and aftershocks display predominance of NW-SE trending and NE dipping normal faulting. Stress inversion of focal mechanisms obtained from the mainshock and aftershock database are compatible with a NE-SW extension under normal faulting regime. The InSAR study shows fringes with two lobes with 4 to 6 cm coseismic slip on a NW-SE elongated and 30-km-long surface deformation consistent with the mainshock location and normal faulting mechanism. The modelling of surface deformation provides the earthquake rupture dimension at depth with ~ 1 m maximum slip on a fault plane striking 315°, dipping 45°, -80° rake and with Mo 7.12 1018 Nm Although the seismic strain rate is of low level, the occurrence of the 2017 Moiyabana earthquake, followed by an aftershock sequence in the central Limpopo belt classifies the intraplate region as an active plate interior.

An earthquake of magnitude Mw 6.5 occurred on the evening of 3 April 2017 in Central Botswana, southern Africa. The event was well recorded by the regional seismic networks. The location by the Council for Geoscience (CGS) placed it near the Central Kgalagadi Game Reserve. Its effects were felt widely in southern Africa and were pronounced for residents of Gauteng and the North West Province in South Africa . In response to this event, the CGS, together with the Botswana Geoscience Institute (BGI), embarked on two scientific projects. The first project involved a macroseismic survey to study the extent and nature of the effects of the event in southern Africa. This involved CGS and BGI scientists soliciting information from members of the public through questionnaire surveys. More information was collected through questionnaires submitted online by the public. In total, 181 questionnaires were obtained through interviews and 151 online from South Africa, Zimbabwe and Namibia through collaboration between the CGS, the Meteorological Services Department of Zimbabwe and the Geological Survey of Namibia. All collected data were analysed to produce 79 intensity data points (IDPs) located all over the region, with maximum intensity values of VI (according to the Modified Mercalli Intensity scale) observed near the epicentre . This is quite a low value of maximum intensity for such a large event, but was expected given that the epicentral region is in a national park which is sparsely populated. The second scientific project involved the rapid installation of a temporary network of six seismograph stations in and around the location of the main event with the purpose of detecting and recording its aftershocks over a period of three months. Data recorded in the first month of April 2017 were collected and delivered to both the CGS and BGI for processing. More than 500 aftershock events of magnitude M L ≥ 0.8 were recorded and analysed for this period. All the events were located at the eastern edge of the Central Kgalagadi Park near the location of the main event in two clear clusters. The observed clusters imply that a segmented fault is the source of these earthquakes and is oriented in a NW-SE direction, similar to the direction inferred from the fault plane solution of the main event.

The April 3, 2017 MW 6.5, Moiyabana (Botswana) earthquake occurred in the continental interior of the Nubian plate and in a seismogenic region previously considered as stable. Our objective is to combine several approaches (field and remote sensing investigations) in order to adopt a multidisciplinary strategy so as to enhance our understanding of earthquake occurrence in intraplate southern Africa. We analyse the mainshock and aftershocks sequence based on a local seismic network and local seismotectonic characteristics. The earthquake rupture geometry is constrained with more than 900 aftershocks recorded over a period of three months and from the InSAR analysis of Sentinel-1 images (ascending orbit). The mainshock (25.134 E, 22.565 S; depth 22 ± 3 km) was followed by more than 500 events of magnitude M ≥ 0.8 recorded in April 2017 including the largest aftershock (MW 4.6 on the April 5, 2017). Focal mechanism solutions of the mainshock and aftershocks display predominance of NW-SE trending and NE dipping normal faulting. Stress inversion of the focal mechanisms produced results that are compatible with a NE-SW extension under normal faulting regime. The InSAR study shows fringes (a pair of ascending images 2017-03-30 and 2017-04-11) with two lobes with 3.86 cm–5.15 cm coseismic slip on a NW-SE elongated and 40-km-long surface deformation consistent with the mainshock location and normal faulting mechanism. The modelling of surface deformation provides the earthquake rupture dimension at depth with ~50 cm maximum slip on a fault plane striking 315°, dipping 45°, −80° rake and with Mo 3.68 × 1018 Nm. Although the seismic strain rate is of low level, the occurrence of the 2017 Moiyabana earthquake, followed by an aftershock sequence in the central Limpopo Mobile Belt classifies the intraplate region as an active plate interior.

Historically, hypocentral depths of earthquakes in South Africa are not well documented from instrumentally determined parameters. We, therefore, investigated a concise number of earthquakes in South Africa over a broad geographical region. We reviewed the hypocentral depths of instrumentally recorded tectonic earthquakes in South Africa through synthetic waveform modeling and through a separate study using multiple phase arrivals. The resulting depths of earthquakes in South Africa occur at shallow crustal depths. It is further shown that uncertainty in focal depth is higher using the multiphase method in comparison with the regional depth‐phase modeling method. Methodology for determining focal depth from macroseismic observations is introduced in this article; however, poor coverage of intensity observations within the epicentral area limited the reliability of this method. Therefore, the study of hypocentral depths inferred from macroseismic observations was inconclusive, resulting from limited intensity data. Shallow depths are, however, inferred from the spatial patterns that do not exhibit the characteristic intensity patterns of deep earthquakes. It was noted during this study that the majority of events display the distinguishable isoseismal pattern of shallow earthquakes, whereas only a selected number of earthquakes exhibit spatial patterns expected of deeper crustal events. The present study did not find conclusive evidence of earthquakes occurring in the lower crust of South Africa from the limited number of earthquakes considered, which therefore indicates a unimodal depth distribution of earthquakes in the upper crust between the depths of 3 and 20 km. This observation contradicts reports in internationally published earthquake catalogs that indicate deeper earthquakes for individual events, for example, the M w ∼6.2 1969 Ceres earthquake.

The occurrence of the September 22, 2016 Manica-Zinave earthquake (Mw5.6) and its subsequent aftershocks provided data to study the physics of earthquakes along the southern end of the East African Rift System (EARS). The event occurred in the southern part of Mozambique, less than 40 km from the epicentre of the Mw7.0 Machaze earthquake, which occurred on February 22, 2006. About 320 aftershocks were recorded within a period of 6 months. The analysis of the Manica-Zinave event and its aftershocks was done to understand the tectonics of the region. The aftershocks were relocated using the double difference method. The focal mechanism for this event shows normal faulting, which is consistent with most events along the EARS. Statistical analysis of the aftershock sequence was performed for the calculation of the b-value and the aftershock decay rate p-value. The b-value and p-value obtained for this sequence are 1.02 and 0.86 respectively. These values are typical of aftershock sequences of heterogeneous stressed regions. Due to its proximity, the event might be an aftershock of the Machaze earthquake, which might have occurred due to stress readjustment within the area. The p-value obtained from the Omori law computation suggests that the region is highly stressed.

New MW–ML magnitude relations valid for the periods January 1971–March 1997, April 1997–September 2012 and October 2012–present are presented for South Africa. Three MW–ML relations were derived for the respective periods by applying a general orthogonal regression using 85 mining-related and tectonic events. Moment magnitudes (MW) were calculated using spectral analysis of the vertical component seismograms. A Brune model for source radiation was assumed. Attenuation functions previously derived from local seismic events were used. For each event, the final MW was computed by taking the average of the values determined at four or more stations. These MW values were used to compute new MW –ML regression equations for three previous ML relations that had been used to compile the South African earthquake catalogue. The new MW–ML relations were then compared with the MW determined from the Harvard Centroid Moment Tensor (CMT) project. The MW computed using the relation derived for the most recent period (October 2012–present) produces MW values that are similar to those reported by the Harvard CMT solutions. The relations can be used in the homogenization of the South African earthquake catalogue. Application of the new relations for the three periods will reduce uncertainty in the homogenized catalogues, which are important when calculating seismic hazard parameters (i.e. when estimating activity rates, b-values and Mmax).

The South African National Seismograph Network operated by the Geophysics Competency of the Council for Geoscience.

Background In developed countries, adolescent and young adult diets have been found to be nutritionally poor. The aim of this study was to examine whether a choice architecture intervention, re-arrangement of produce within a grocery store to increase the accessibility of fruit and vegetables, affected purchasing behaviour on a university campus. Methods A database of daily sales data from January 2012 to July 2017 was obtained from a campus grocery store. Two changes to the layout were made during this time period. In January 2015, fruit and vegetables were moved from the back of the store, furthest from the entrance, to the aisle closest to the entrance and an entrance-facing display increasing their accessibility. In April 2016, the entrance-facing display of fruit and vegetables was replaced with a chiller cabinet so that fruit and vegetables remained more accessible than during the baseline period, but less accessible than in the period immediately previously. A retrospective interrupted time series analysis using dynamic regression was used to model the data and to examine the effect of the store re-arrangements on purchasing. All analyses were carried out both for sales-by-quantity and for sales-by-money. Results The first shop re-arrangement which made fruit and vegetables more prominent, increased the percentage of total sales that were fruit and vegetables, when analysed by either items purchased or money spent. The second rearrangement also had a positive effect on the percentage of total sales that were fruit and vegetables compared to baseline, however this was not significant at the 5% level. Over the five year period, the percentage of sales that were fruit and vegetables declined both in terms of items purchased, and money spent. Conclusions Increasing accessibility of fruit and vegetables in a grocery store is a feasible way to improve the diet of students in tertiary education. There is evidence of declining fruit and vegetable consumption among the studied population, which should be further investigated. Electronic supplementary material The online version of this article (10.1186/s12889-018-6063-8) contains supplementary material, which is available to authorized users.

Online Material: Tables of explosions, mining‐related events, and tectonic earthquakes located during this study. During the period October 2000 to December 2005, 5806 regional earthquake epicenters were determined during routine analysis with the SEISAN software (Ottemoller et al. , 2012) as recorded by the South African National Seismograph Network (SANSN). A total of 1380 of these epicenters were determined through the three‐component single‐station location method (Roberts et al. , 1989), as implemented within the SEISAN software (Ottemoller et al. , 2012). These events, located through the single‐station location method, are included in the South African National Seismological Database (SANSD), with magnitudes ranging from M −0.9 to 4.4. The area of interest and the geographic distribution of data reported in this study are shown in Figure 1. The solid black circles denote events recorded through the iterative least‐squares method, and the gray circles denote events located with the single‐station location method. The polygons with black outlines define seismic clusters (Du Plessis, 1996) and the hatched polygon the Wits basin (Singh et al. , 2009). Figure 1. The study area (inset) and distribution of earthquake epicenters determined through the single‐station (gray circles) and multistation least‐squares (black circles) location methods during the period October 2000–December 2005. The polygons outlined with black borders demarcate seismic clusters defined by Du Plessis (1996): 1, Springbok/Kamieskroon; 2, Grootvloer; 3, Ceres; 4, Koffiefontein; 5, eastern Lesotho; 6, Matatiele; and 7, Phalaborwa. The broken lines indicated as 8 and 9 on the map show the extent of the Kango–Baviaanskloof and Worcester faults, respectively (Du Plessis, 1996). The hatched polygon (10) defines the Wits basin (Singh et al. , 2009). Clusters related to mining operations are indicated in Figure 5. The practice of evaluating earthquake epicenters at the Council for Geoscience (CGS) with the single‐station method was introduced as a result of an …

Natural carbon dioxide (CO2) emanates from a number of sites along a N-S trend that coincides with a mapped fault near the village of Bongwana in KwaZulu-Natal, South Africa. In addition to the natural CO2 seeps a groundwater well drilled on a farm in Bongwana encountered CO2 and now leaks. Thus the Bongwana sites provide excellent analogues for failed CO2 storage under the two primary leakage scenarios; 1) abrupt leakage through injection well failure or leakage up an abandoned well, and 2) gradual leakage, through undetected faults, fractures or wells. Here we present results from preliminary fieldwork undertaken in September 2015.

To ensure the effective long-term storage of CO2 in candidate geological storage sites, evaluation of potential leakage pathways to the surface should be undertaken. Here we use a series of natural CO2 seeps along a fault in South Africa to assess the controls on CO2 leakage to the surface. Geological mapping and detailed photogrammetry reveals extensive fracturing along the mapped fault trace. Measurements of gas flux and CO2 concentration across the fracture corridor give maximum soil gas measurements of 27% CO2 concentration and a flux of 191 g m−2 d−1. These measurements along with observations of gas bubbles in streams and travertine cones attest to CO2 migration to the surface. Permeability measurements on the host rock units show that the tillite should act as an impermeable seal to upward CO2 migration. The combined permeability and fracture mapping data indicate that fracture permeability creates the likely pathway for CO2 migration through the low permeability tillite to the surface. Heterogeneity in fracture connectivity and intensity at a range of scales will create local higher permeability pathways along the fracture corridor, although these may seal with time due to fluid-rock interaction. The results have implications for the assessment and choice of geological CO2 storage sites, particularly in the assessment of sub-seismic fracture networks.

Importance The human patient simulators that are currently used in multidisciplinary operating room team training scenarios cannot simulate surgical tasks because they lack a realistic surgical anatomy. Thus, they eliminate the surgeon’s primary task in the operating room. The surgical trainee is presented with a significant barrier when he or she attempts to suspend disbelief and engage in the scenario. Objective To develop and test a simulation-based operating room team training strategy that challenges the communication abilities and teamwork competencies of surgeons while they are engaged in realistic operative maneuvers. Design, Setting, and Participants This pre-post educational intervention pilot study compared the gains in teamwork skills for midlevel surgical residents at Wake Forest Baptist Medical Center after they participated in a standardized multidisciplinary team training scenario with 3 possible levels of surgical realism: (1) SimMan (Laerdal) (control group, no surgical anatomy); (2) “synthetic anatomy for surgical tasks” mannequin (medium-fidelity anatomy), and (3) a patient simulated by a deceased donor (high-fidelity anatomy). Interventions Participation in the simulation scenario and the subsequent debriefing. Main Outcomes and Measures Teamwork competency was assessed using several instruments with extensive validity evidence, including the Nontechnical Skills assessment, the Trauma Management Skills scoring system, the Crisis Resource Management checklist, and a self-efficacy survey instrument. Participant satisfaction was assessed with a Likert-scale questionnaire. Results Scenario participants included midlevel surgical residents, anesthesia providers, scrub nurses, and circulating nurses. Statistical models showed that surgical residents exposed to medium-fidelity simulation (synthetic anatomy for surgical tasks) team training scenarios demonstrated greater gains in teamwork skills compared with control groups (SimMan) (Nontechnical Skills video score: 95% CI, 1.06-16.41; Trauma Management Skills video score: 95% CI, 0.61-2.90) and equivalent gains in teamwork skills compared with high-fidelity simulations (deceased donor) (Nontechnical Skills video score: 95% CI, −8.51 to 6.71; Trauma Management Skills video score: 95% CI, −1.70 to 0.49). Conclusions and Relevance Including a surgical task in operating room team training significantly enhanced the acquisition of teamwork skills among midlevel surgical residents. Incorporating relatively inexpensive, medium-fidelity synthetic anatomy in human patient simulators was as effective as using high-fidelity anatomies from deceased donors for promoting teamwork skills in this learning group.

A relation to determine local magnitude (ML) based on the original Richter definition is empir- ically derived from synthetic Wood-Anderson seismo- grams recorded by the South African National Seismograph Network. In total, 263 earthquakes in the distance range 10 to 1,000 km, representing 1,681 trace amplitudes measured in nanometers from synthesized Wood-Anderson records on the vertical channel were considered to derive an attenuation rela- tion appropriate for South Africa through multiple regression analysis. Additionally, station corrections were determined for 26 stations during the regression analysis resulting in values ranging between −0.31 and 0.50. The most appropriate ML scale for South Africa from this study satisfies the equation: ML ¼ log10ðA Þþ 1:149 log10ðR Þþ 0:00063R þ 2:04 � S The anelastic attenuation term derived from this study indicates that ground motion attenuation is sig- nificantly different from Southern California but com- parable with stable continental regions.

BACKGROUND Short-chain fatty acids (SCFAs) maintain human colonic function and may help prevent colonic disease. A study with ileostomists showed that starches acylated with specific SCFAs largely survive passage through the small intestine, but the percentage released in the colon has not been established. OBJECTIVE The objective was to determine the percentage of ingested esterified butyrate released in the human gastrointestinal tract. DESIGN The study was a randomized, crossover, controlled trial consisting of baseline and four 2-wk periods during which 16 volunteers consumed diets low in resistant starch plus 20 and 40 g cooked high-amylose maize starch (HAMS: HAMS20 or HAMS40) or butyrylated HAMS (HAMSB20 or HAMSB40) daily. HAMSB20 contained 31.8 mmol esterified butyrate. Complete 48-h fecal collections were made on days 2-3 and 12-13 of each period. RESULTS Free fecal butyrate concentrations were higher after HAMSB40 than after HAMSB20 (P < 0.005) and HAMS (P < 0.0001) and higher than baseline data (P < 0.0001). Fecal esterified butyrate concentrations were highest in the HAMSB40 (days 12-13; P < 0.0001) group, and concentrations in the HAMSB40 (days 2-3) and HAMSB20 groups were higher than those in the HAMS groups and those at baseline (P < 0.0001). Ingestion of HAMSB20 and HAMSB40 resulted in the release of 26.8 ± 1.0 and 50.2 ± 2.4 mmol butyrate/d (days 12-13) (84.2 ± 3.0% and 79.0 ± 3.1% of total ingested esterified butyrate), respectively, in the gastrointestinal tract. By calculation, ∼57.2% of ingested esterified butyrate was released in the colon. Microbial analysis showed that this release was probably facilitated mainly by Parabacteroides distasonis, which increased in abundance with HAMSB40 (days 12-13) (P < 0.001). CONCLUSIONS This study shows that cooked butyrylated starch delivers esterified butyrate to the human colon effectively and has the potential to improve human bowel health. This trial is registered in the Australian Clinical Trials Registry as ACTRN012606000398505.

Seismic activity recorded by the South African National Seismograph Network in southern Africa during the period January to December 2006 is summarized in this article. The South African National Seismograph Network was expanded to 23 seismological stations and the data communication infrastructure updated to transmit continuous waveform data in near real-time during 2006. Earthquake data, published in the Seismological Bulletins of the Council for Geoscience for 2006, was revisited and all tectonic earthquakes relocated together with mining related earthquakes that were located outside known mine boundaries. The resulting earthquake database comprises a total of 3875 located seismic events, the majority of which (79%) is located in the gold and platinum mines of South Africa. A total of 1460 events were ascribed to chemical explosions in opencast mines and quarries and flagged accordingly in the database. The recorded seismic activity, tectonic as well as mining-related, is discussed in terms of the error in location and the observed frequency-magnitude distribution. A fault plane solution for a M L =4.0 earthquake, located in the gold mines of South Africa, is also presented. The most significant earthquake occurred on the southernmost extension of the East African Rift System in south-western Mozambique and measured 7.0 on the moment magnitude scale. The earthquake was widely felt throughout the region, causing four fatalities, 27 injuries and damage to approximately 160 buildings.

The hippocampus is hypothesised to be critical for episodic memory in humans and episodic-like memory in animals. Human data regarding the roles of the various subregional networks within the hippocampus is difficult to obtain. In this article we examine the current rodent literature on episodic-like memory and associative recognition and review the roles of the hippocampal subregions in these behavioural tasks. We focus on the large amount of recent data reporting roles for CA3 and CA1 in allocentric spatial and temporal associative memory respectively. Our own recent data are then presented detailing critical roles for CA3 and CA1 in an associative recognition task which does not require allocentric spatial or temporal processing. These data support more generic roles for CA3 and CA1 in episodic-like memory, based on anatomical and theoretical literature on hippocampal function. We also present a novel analysis of our data in which we suggest that the encoding of object, place and context information is unaffected by lesions of the hippocampus and therefore infer that it may be the storage or retrieval phase of this associative memory which is critically dependent on hippocampal function. In conclusion however, more specific anatomically and temporally controlled methods are needed to fully define the role of hippocampal subregions in episodic-like memory.

Background Anesthesia simulators can generate reproducible, standardized clinical scenarios for instruction and evaluation purposes. Valid and reliable simulated scenarios and grading systems must be developed to use simulation for evaluation of anesthesia residents. Methods After obtaining Human Subjects approval at each of the 10 participating institutions, 99 anesthesia residents consented to be videotaped during their management of four simulated scenarios on MedSim or METI mannequin-based anesthesia simulators. Using two different grading forms, two evaluators at each department independently reviewed the videotapes of the subjects from their institution to score the residents' performance. A third evaluator, at an outside institution, reviewed the videotape again. Statistical analysis was performed for construct- and criterion-related validity, internal consistency, interrater reliability, and intersimulator reliability. A single evaluator reviewed all videotapes a fourth time to determine the frequency of certain management errors. Results Even advanced anesthesia residents nearing completion of their training made numerous management errors; however, construct-related validity of mannequin-based simulator assessment was supported by an overall improvement in simulator scores from CB and CA-1 to CA-2 and CA-3 levels of training. Subjects rated the simulator scenarios as realistic (3.47 out of possible 4), further supporting construct-related validity. Criterion-related validity was supported by moderate correlation of simulator scores with departmental faculty evaluations (0.37-0.41, P < 0.01), ABA written in-training scores (0.44-0.49, < 0.01), and departmental mock oral board scores (0.44-0.47, P < 0.01). Reliability of the simulator assessment was demonstrated by very good internal consistency (alpha = 0.71-0.76) and excellent interrater reliability (correlation = 0.94-0.96; P < 0.01; kappa = 0.81-0.90). There was no significant difference in METI versus MedSim scores for residents in the same year of training. Conclusions Numerous management errors were identified in this study of anesthesia residents from 10 institutions. Further attention to these problems may benefit residency training since advanced residents continued to make these errors. Evaluation of anesthesia residents using mannequin-based simulators shows promise, adding a new dimension to current assessment methods. Further improvements are necessary in the simulation scenarios and grading criteria before mannequin-based simulation is used for accreditation purposes.

Acoustic emission (AE) from pure and mixed mode fatigue fracture of adhesive composite joints was recorded and analyzed. Transient AE signal classification was attempted by a computational pattern recognition analysis. Good separation was achieved for pure mode AE signals from the double cantilever beam (mode I) and end notch fracture (mode II) tests. AE signals from the mixed mode lap joint test were found to be closer to the mode II fracture signals. The results may provide insight into the fracture mechanisms in joints and can be used for the development of mechanism-based predictive models of fracture and life.

One of the challenges facing organisations and consultants, when they are working together on change and business improvement, is the initial identification of the ‘problem’. This paper sets out benefits to an organisation in carrying out regular diagnostic reviews — and describes an effective framework. The framework takes a systemic and holistic view of organisations — a key to organisational health. The four elements in the framework — Strategy, People, Enablers and Leadership – offer an effective way for an organisation to check its health and fitness for success.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated., Genome-wide linkage studies have identified the 9q22 chromosomal region as linked with colorectal cancer (CRC) predisposition. A candidate gene in this region is transforming growth factor β receptor 1 (TGFBR1). Investigation of TGFBR1 has focused on the common genetic variant rs11466445, a short exonic deletion of nine base pairs which results in truncation of a stretch of nine alanine residues to six alanine residues in the gene product. While the six alanine (*6A) allele has been reported to be associated with increased risk of CRC in some population based study groups this association remains the subject of robust debate. To date, reports have been limited to population-based case–control association studies, or case–control studies of CRC families selecting one affected individual per family. No study has yet taken advantage of all the genetic information provided by multiplex CRC families.

In recent years, much work has been carried out in interface design and service quality in order to maximise user experience and sustain engagement. We are often unsure, however, what factors really influence user interactions with the technologies. Here we report on an ongoing examination of the relationships between user demographics, self reported attitudes, efficacy, and system feature, and participation on an online diet support site. Our findings indicate that not only the characteristics of the users themselves are associated with sustained engagement with a weight loss site, but also that usage of particular features on the site results in higher return rates. These findings support a push for designers to understand their users and features of their site, in order to maximise engagement with their target audiences.

(1994). Richard Rorty and Star Wars: on the nature of pragmatism's narrative. Textual Practice: Vol. 8, No. 3, pp. 435-448.

MANIFEST (the Many Instrument Fiber System) is a proposed fiber-positioner for the GMT, capable of feeding other instruments as needed. It is a simple, flexible and modular design, based on the AAO's Starbugs, the University of Sydney's Hexabundles, and extensive use of standard telecommunications fiber technology. Up to 2000 individually deployable fiber units are envisaged, with a wide variety of aperture types (single-aperture, image-slicing, IFU). MANIFEST allows (a) full use of the GMT's 20' field-of-view, (b) a multiplexed IFU capability, (c) greatly increased spectral resolution via image-slicing, (d) efficient detector packing both spectrally and spatially, (e) the possibility of OH-suppression in the near-infrared. Together, these gains make GMT the most powerful of the ELT's for wide-field spectroscopy. It is intended that MANIFEST will form part of the GMT facility itself, available to any instrument able to make use of it.

We report on the technological achievements of our latest Starbug prototypes and their implications for smart focal plane fiber positioning applications for wide-field astronomy. The Starbugs are innovative self-motile miniature robotic devices that can simultaneously and independently position fibers or payloads over a field plate located at the telescope's focal plane. The Starbugs concept overcomes many of the limitations associated with the traditional 'pick and place' positioners where a robot places fixed buttons onto the field plate. The new Starbug prototypes use piezoelectric actuators and have the following features: (i) new 'lift-and-step' method (discrete step) for accurate positioning over different surfaces; and (ii) operate in an inverted hanging position underneath a transparent field plate, removing the need for fibercable retractors. In this paper, we present aspects of the Starbug prototypes, including the theoretical model, mechanical design, experimental setup, algorithms, performance and applications for astronomical instrumentation.

The AAO is building an optical high resolution multi-object spectrograph for the AAT for Galactic Archaeology. The instrument has undergone significant design revision over that presented at the 2008 Marseilles SPIE meeting. The current design is a 4-channel VPH-grating based spectrograph providing a nominal spectral resolving power of 28,000 and a high-resolution mode of 45,000 with the use of a slit mask. The total spectral coverage is about 1000 Angstroms for up to 392 simultaneous targets within the 2 degree field of view. Major challenges in the design include the mechanical stability, grating and dichroic efficiencies, and fibre slit relay implementation. An overview of the current design and discussion of these challenges is presented.

This resource is a series of eight simulated critical medical incidents designed for graduating medical students to rehearse their diagnosis and management skills. Each case is presented in one folder, which contains a scenario summary, a slide presentation, and the patient and scenario simulator files. Several of the folders also contain electrocardiograms and chest radiographs. The goal for this series is to give graduating students a facilitated transition from classroom learning and passive clinical experiences to active clinical care in the urgent medical environment. Education concepts addressed include both management of the medical issues and teamwork and active problem-solving skills that are inadequately addressed in other parts of the curriculum. Each scenario lasts about 15 to 20 minutes, with a 10-minute faculty-facilitated debriefing that follows. Simulation is an engaging, interactive, and relevant framework for learning; it is also widely popular with medical learners, as described in many contexts over the last 10 years. This course in particular has been popular with participants for its 6 years of production, according to oral feedback and surveys. A survey of participants revealed that 42 out of the 43 respondents recommended the simulation series be continued with future classes. Several students from each class commented that the sessions were very helpful and should be required for all students.

Reliable local earthquake locations depend on many factors, a major one of which is the velocity model. Locating earthquakes using unreliable models contributes in part to the uncertainties of active fault mapping and unexplained scatter of s eismic locations. Given that we strive to continually improve our locating abilities, it is necessary to always improve on the model, when possible. The South African National Seismograph Network (SANSN) has been using a model (Saunders et al. 2006) from work published by Wright et al. (2002) and refined by Brandt (2005). Even though there have been many crust and mantle structure studies in South Africa ( e.g. , Nguuri et al. 2001; Simon et al. 2002; Wright et al. 2002; James et al. 2004), the models obtained are too complicated for use in seismic event locations, especially when using the earthquake analysis software SEISAN (Havskov and Ottemoller 2008). The HYPOCENTER program (Lienert 1994), which is the location program in SEISAN, cannot use models with low-velocity layers, because these usually introduce instabilities. Modification/refinement of the results of one of these studies (Wright et al. 2002) by Brandt (2005) produced a model that the SANSN is currently using in earthquake locations. This model can therefore be used as a starting point in conducting local earthquake tomography to obtain a more realiable model. Our study aims to compute a 1-D velocity model for South Africa by inverting P -wave travel times recorded by SANSN. Ideally, SANSN should use different models for the different major tectonic units in South Africa, i.e. , Kaapvaal craton, Namaqualand, and Cape Fold belt. However, available data dictates what can be done, and for now we can only produce a 1-D model whose velocities are approximately equal to the average velocity of the 3-D structure within the same …

We apply two recent non-linear, image-processing algorithms to colour image compression. The two algorithms are colorization and joint bilateral filtering. Neither algorithm was designed for image compression. Our investigations were to ascertain whether their mechanisms could be used to improve the image compression rate for the same level of visual quality. Both show interesting behaviour, with the second showing a visible improvement in visual quality, over JPEG, at the same compression rate. In both cases, we store luminance as a standard, lossily compressed, greyscale image and store colour at a very low sampling rate. Each of the non-linear algorithms then uses the information from the luminance channel to determine how to propagate the colour information appropriately to reconstruct a full colour image.

A simple method of inferring the genotyping error rate of SNP arrays and similar high-throughput genotyping methods from Mendelian errors is described. Application to genotypes from small families using the Affymetrix GeneChip Human Mapping 50 k Array indicates an error rate of about 0.1%, and this rate can be reduced by increasing the quality criterion for calls, though at the cost of a reduced genotype call rate, which limits the benefit available. Simulated data are used to show that the number of SNPs on this array is sufficient for such a low error rate to have little impact on identical by descent-based inference for disease linkage in sib-pair studies.

The statistical properties required for effective biomarkers for disease are examined. It is shown that an "effectiveness parameter" D can be calculated that summarises the performance of a given biomarker and can distinguish between effective and ineffective biomarkers. D can be readily calculated from published summaries of biomarker levels and provides a simpler alternative to the commonly used "Area under the Curve" statistic. The impact of within-individual and between-individual variation in biomarker levels is also evaluated. An approach to the choice of sample size for experiments to estimate D is described.