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BACKGROUND: In neonatal intensive care, a child's death is often preceded by a medical decision. Nurses, social workers and pastors, however, are often excluded from ethical case deliberation. If multiprofessional ethical case deliberations do take place, participants may not always know how to perform to the fullest. SETTING: A level-IIID neonatal intensive care unit of a paediatric teaching hospital in the Netherlands. METHODS: Structured multiprofessional medical ethical decision-making (MEDM) was implemented to help overcome problems experienced. Important features were: all professionals who are directly involved with the patient contribute to MEDM; a five-step procedure is used: exploration, agreement on the ethical dilemma/investigation of solutions, analysis of solutions, decision-making, planning actions; meetings are chaired by an impartial ethicist. A 15-item questionnaire to survey staff perceptions on this intervention just before and 8 months after implementation was developed. RESULTS: Before and after response rates were 91/105 (87%) and 85/113 (75%). Factor analysis on the questionnaire suggested a four-factor structure: participants' role; structure of MEDM; content of ethical deliberation; and documentation of decisions/conclusions. Effect sizes were 1.67 (p<0.001), 0.69 (p<0.001) and 0.40 (p<0.01) for the first three factors respectively, but only 0.07 (p=0.65) for the fourth factor. Nurses' perceptions of improvement did not significantly exceed those of physicians. CONCLUSION: Professionals involved in ethical case deliberation perceived that the process of decision-making had improved; they were more positive about the structure of meetings, their own role and, to some extent, the content of ethical deliberation. Documentation of decisions/conclusions requires further improvement. [ABSTRACT FROM AUTHOR]

Although signatures of superconductivity in Dirac semimetals have been reported, for instance by applying pressure or using point contacts, our understanding of the topological aspects of Dirac semimetal superconductivity is still developing. Here, we utilize nanoscale phase-sensitive junction technology to induce superconductivity in the Dirac semimetal Bi 1-x Sb x . Our radiofrequency irradiation experiments then reveal a significant contribution of 4π-periodic Andreev bound states to the supercurrent in Nb-Bi 0.97 Sb 0.03 -Nb Josephson junctions. The conditions for a substantial 4π contribution to the supercurrent are favourable because of the Dirac cone's very broad transmission resonances and a measurement frequency faster than the quasiparticle poisoning rate. In addition, we show that a magnetic field applied in the plane of the junction allows tuning of the Josephson junctions from 0 to π regimes. Our results open the technologically appealing avenue of employing the topological bulk properties of Dirac semimetals for topological superconductivity research and topological quantum computer development.

Objective: We reviewed our decisions about continuation/withdrawal of life-sustaining treatments in a group of critically ill newborns who were discussed in structured medical ethical decision-making meetings, and provide the surviving children's outcomes at 2-year follow-up., Study Design: In an explorative observational study, 61 cases were evaluated. The children involved had been discussed in such a structured way from 2009 to 2012 in a level III-D neonatal intensive care unit., Results: Decisions made were: full treatment (n=6), earlier restriction cancelled (n=3), treatment restriction (n=30) and palliative care (n=22). Parents of six children disagreed with the decision proposed. Thirteen (54%) of the 24 children who survived (39%) had moderate to severe neurological problems; 8 (33%) had additional sequelae; only one 2-year-old child was healthy., Conclusions: Decisions made varied to a large extent. The poor outcomes should be disseminated among decision makers. Future studies must explore new ways to improve outcome prediction, extend follow-up periods and consider what living with severe handicaps really means for both child and family.

The two-dimensional electron system at the interface between LaAlO&#95;{3} and SrTiO&#95;{3} has several unique properties that can be tuned by an externally applied gate voltage. In this work, we show that this gate tunability extends to the effective band structure of the system. We combine a magnetotransport study on top-gated Hall bars with self-consistent Schrödinger-Poisson calculations and observe a Lifshitz transition at a density of 2.9×10^{13}cm^{-2}. Above the transition, the carrier density of one of the conducting bands decreases with increasing gate voltage. This surprising decrease is accurately reproduced in the calculations if electronic correlations are included. These results provide a clear, intuitive picture of the physics governing the electronic structure at complex-oxide interfaces.

Purpose To summarize existing evidence of thoracic magnetic resonance (MR) imaging in determining the nodal status of non-small cell lung cancer (NSCLC) with the aim of elucidating its diagnostic value on a per-patient basis (eg, in treatment decision making) and a per-node basis (eg, in target volume delineation for radiation therapy), with results of cytologic and/or histologic examination as the reference standard. Materials and Methods A systematic literature search for original diagnostic studies was performed in PubMed, Web of Science, Embase, and MEDLINE. The methodologic quality of each study was evaluated by using the Quality Assessment of Diagnostic Accuracy Studies 2, or QUADAS-2, tool. Hierarchic summary receiver operating characteristic curves were generated to estimate the diagnostic performance of MR imaging. Subgroup analyses, expressed as relative diagnostic odds ratios (DORs) (rDORs), were performed to evaluate whether publication year, methodologic quality, and/or method of evaluation (qualitative [ie, lesion size and/or morphology] vs quantitative [eg, apparent diffusion coefficients in diffusion-weighted images]) affected diagnostic performance. Results Twelve of 2551 initially identified studies were included in this meta-analysis (1122 patients; 4302 lymph nodes). On a per-patient basis, the pooled estimates of MR imaging for sensitivity, specificity, and DOR were 0.87 (95% confidence interval [CI]: 0.78, 0.92), 0.88 (95% CI: 0.77, 0.94), and 48.1 (95% CI: 23.4, 98.9), respectively. On a per-node basis, the respective measures were 0.88 (95% CI: 0.78, 0.94), 0.95 (95% CI: 0.87, 0.98), and 129.5 (95% CI: 49.3, 340.0). Subgroup analyses suggested greater diagnostic performance of quantitative evaluation on both a per-patient and per-node basis (rDOR = 2.76 [95% CI: 0.83, 9.10], P = .09 and rDOR = 7.25 [95% CI: 1.75, 30.09], P = .01, respectively). Conclusion This meta-analysis demonstrated high diagnostic performance of MR imaging in staging hilar and mediastinal lymph nodes in NSCLC on both a per-patient and per-node basis. (©) RSNA, 2016 Online supplemental material is available for this article.

Background: Perceived constraints to providing patient care in their own morally justified way may cause moral distress (MD) in neonatal nurses and physicians. Negative long-term effects of MD include substandard patient care, burnout and leaving the profession., Aim: To assess the immediate impact of perceived inappropriate patient care on nurses' and physicians' MD intensity, and explore a possible moderating effect of ethical climate., Design: In a repeated measures design, after baseline assessment, each participant completed self-report questionnaires after five randomly selected shifts. Data were analysed with logistic and Tobit regression., Participants: Data were collected among 117 of 147 eligible nurses and physicians (80%) in a level-III neonatal intensive care unit in the Netherlands., Results: At baseline, overall MD was relatively low; in nurses, it was significantly higher than in physicians. Few morally distressing situations were reported in the repeated measurements, but distress could be intense in these cases; nurses' and physicians' scores were comparable. Physicians were significantly more likely than nurses to disagree with their patients' level of care (p = 0·02). Still, perceived overtreatment, but not undertreatment, was significantly related to distress intensity in both professional groups; ethical climate did not moderate this effect. Substandard patient care due to lack of continuity, poor communication and unsafe levels of staffing were rated as more important causes of MD than perceived inappropriate care., Conclusions: Although infrequently perceived, overtreatment of patients caused considerable distress in nurses and physicians. Our unit introduced multidisciplinary medical ethical decision making 5 years ago, which may partly explain the low MD at baseline., Relevance to Clinical Practice: MD might be prevented by improved continuity of care, safe levels of staffing and better team communication, along with other targeted interventions with demonstrated effectiveness, such as palliative care programs and facilitated ethics conversations., (© 2015 British Association of Critical Care Nurses.)

This article introduces the Game Maturity Model for the healthcare industry as an extension to the general Game Maturity Model and describes the usage by two case studies of applied health games. The Game Maturity Model for healthcare provides a practical and value-adding method to assess existing games and to determine strategic considerations for application of applied health games. Our forecast is that within 5 years the use and development of applied games will have a role in our daily lives and the way we organize health care that will be similar to the role social media has today.

In this note, the feasibility of complementing our hybrid 1.5 T MRI linac (MRL) with a megavoltage (MV) portal imager is investigated. A standard aSi MV detector panel is added to the system and both qualitative and quantitative performances are determined. Simultaneous MR imaging and transmission imaging can be performed without mutual interference. The MV image quality is compromised by beam transmission and longer isocentre distance; still, the field edges and bony anatomy can be detected at very low dose levels of 0.4 cGy. MV imaging integrated with the MRL provides an independent and well-established position verification tool, a field edge check and a calibration for alignment of the coordinate systems of the MRI and the accelerator. The portal imager can also be a valuable means for benchmarking MRI-guided position verification protocols on a patient-specific basis in the introductory phase.

Haemophilus ducreyi is a well recognised causative agent of genital ulcers and chancroid. We report two unusual cases of non-sexually transmitted H. ducreyi infection leading to chronic lower limb ulcers. Both patients were Australian expatriates visiting Australia from the Pacific Islands--one from Papua New Guinea and the other from Vanuatu.

Purpose: For neonates receiving intensive care, nasogastric tube feeding is essential. Since nasogastric tube placement techniques are not well standardized and common verification methods can be unreliable, placement errors may lead to unsafe situations. In mechanically ventilated neonates and neonates on continuous positive airway pressure, malpositioning of the nasogastric tube may prevent excess air within the stomach to escape. In this study, we aimed to relate tube position to amount of air. The hypothesis was: the better the position of the tube, the smaller the amount of air in the stomach., Subjects: A 1-year cohort of neonates in a level IIIc neonatal intensive care unit with a nasogastric tube., Design and Methods: We retrospectively reviewed 326 radiographs and classified nasogastric tube position and gastric air. Descriptive statistics were used to describe demographic data. Kendal's tau statistic was applied to explore the relationship between nasogastric tube position and amount of gastric air. A Mann-Whitney U test was performed to confirm the differences in gastric air in neonates with Ch5 and Ch6 gastric tubes and neonates with Ch8 gastric tubes., Results: One or both orifices of nasogastric tubes were in the esophagus in 7.1% of cases, tubes were curled up in the stomach in 35.3% of cases, and tube tips were beyond the pyloric sphincter in 5.5% of cases. Substantial or excessive air was found in 37.7% of cases. Kendal's tau value indicated that there was no significant correlation between nasogastric tube position and gastric air. The Mann-Whitney U value indicated that children with Ch5 and Ch6 gastric tubes had significantly more gastric air than children with Ch8 gastric tubes., Conclusion: Nasogastric tubes were malpositioned in nearly half of cases, and substantial or excessive air was found in more than one-third of cases. The hypothesis-the better the position of the tube, the smaller the amount of gastric air-was not confirmed by the data. However, a significant relationship was found between tube size and gastric air.

A new method for portal dosimetry using CCD camera-based electronic portal imaging devices (CEPIDs) is demonstrated. Unlike previous approaches, it is not based on a priori assumptions concerning CEPID cross-talk characteristics. In this method, the nonsymmetrical and position-dependent cross-talk is determined by directly imaging a set of cross-talk kernels generated by small fields ("pencil beams") exploiting the high signal-to-noise ratio of a cooled CCD camera. Signal calibration is achieved by imaging two reference fields. Next, portal dose images (PDIs) can be derived from electronic portal dose images (EPIs), in a fast forward-calculating iterative deconvolution. To test the accuracy of these EPI-based PDIs, a comparison is made to PDIs obtained by scanning diode measurements. The method proved accurate to within 0.2+/-0.7% (1 SD), for on-axis symmetrical and asymmetrical fields with different field widths and homogeneous phantom thicknesses, off-axis Alderson thorax fields and a strongly modulated IMRT field. Hence, the proposed method allows for fast, accurate portal dosimetry. In addition, it is demonstrated that the CEPID cross-talk signal is not only induced by optical photon reflection and scatter within the CEPID structure, but also by high-energy back-scattered radiation from CEPID elements (mirror and housing) towards the fluorescent screen.

Reliable application of advanced external beam techniques for the treatment of patients with cancer, such as intensity modulated radiotherapy, requires an adequate quality assurance programme for the verification of the dose delivery. Accurate patient positioning is mandatory because of the steep dose gradients outside the tumour volume. Owing to the increased complexity of the treatment planning and delivery techniques, verification of the dose delivery before and during the actual patient treatment is equally important. For this purpose, a quality assurance programme has been established in our clinic that is primarily based on measurements with electronic portal imaging devices. To minimise systematic set-up errors, the patient positioning is measured in the first few treatment fractions and a set-up correction is applied in the subsequent ones. Before the first treatment fraction, portal dose measurements are performed for each treatment field with the electronic portal imaging device to verify that the planned fluence distribution is correctly delivered at the treatment unit. Dosimetric measurements are also performed during patient treatment to derive the actually delivered fluence maps. By combining this information with knowledge on the patient set-up, the delivered 3-D dose distribution to both the tumour and sensitive organs may be assessed. However, for the highest accuracy, exact knowledge on the (internal) patient geometry during treatment, e.g. using a cone-beam CT, is required.

Our EPIDs have recently been equipped with Peltier-cooled CCD cameras. The CCD cooling dramatically reduced deteriorating effects of radiation damage on image quality. Over more than 600 days of clinical operation, the radiation induced noise contribution has remained stable at a very low level (1 SD < or = 0.15% of the camera dynamic range), in marked contrast with the previously used noncooled cameras. The camera response (output signal versus incident EPID radiation exposure) can be accurately described with a quadratic function. This response reproduced well, both in short and long term (variation < 0.2% respectively < 0.4% (1 SD)), rendering the cooled camera well-suited for EPID dosimetry applications.

Off-line patient setup correction protocols based on electronic portal images are an effective tool to reduce systematic patient setup errors. Recently, we have introduced the no action level (NAL) protocol which establishes a significant error reduction at a very small workload. However, this protocol did not include an explicit verification of the applied setup corrections. Systematic mistakes in the execution of setup corrections (e.g., a setup correction is always executed in the +X direction whereas a correction in the -X direction was prescribed) may introduce large systematic setup errors (irrespective of the setup protocol) and may seriously impair treatment outcome. We have therefore extended the NAL protocol with a correction verification (COVER) stage, solely aimed at detecting such mistakes. In short, COVER tests the magnitude of the postcorrection setup error in each relevant direction. If these residue errors are below the acceptance threshold T, no more electronic portal images are required and the protocol has finished. If not, the origin of this result should be investigated; if no obvious mistakes are present, the procedure is repeated for one more treatment fraction. If the residue setup errors are confirmed to be larger than T, the entire protocol is restarted. Using both Monte Carlo simulations and analytical calculations, we performed a risk analysis and evaluated the workload for various choices of T. A threshold T = 3 x sigma(r), where sigma(r) is the mean standard deviation of the random setup errors, ensured that (1) COVER introduces only a small additional workload (1.05 measurement per patient, while the absolute minimum is 1.0) and (2) serious correction mistakes are detected with high probability. Even if setup corrections are wrongly applied in each patient (worst case scenario), COVER ensures that the final distribution of systematic errors is not wider than the precorrection distribution of systematic errors; for realistic frequencies of correction mistakes (<< 1 per patient) this distribution becomes much more narrow. The combination of NAL and COVER thus provides a highly efficient as well as safe method to reduce systematic setup errors.

The application of a newly developed fluoroscopic (CCD-camera based) electronic portal imaging device (EPID) in portal dosimetry is investigated. A description of the EPID response to dose is presented in terms of stability, linearity and optical cross-talk inside the mechanical structure. The EPID has a relatively large distance (41 cm on-axis) between the fluorescent screen and the mirror (high-elbow), which results in cross-talk with properties quite different from that of the low-elbow fluoroscopic EPIDs that have been studied in the literature. In contrast with low elbow systems, the maximum cross-talk is observed for points of the fluorescent screen that have the largest distance to the mirror, which is explained from the geometry of the system. An algorithm to convert the images of the EPID into portal dose images (PDIs) is presented. The correction applied for cross-talk is a position dependent additive operation on the EPID image pixel values, with a magnitude that depends on a calculated effective field width. Deconvolution with a point spread function, as applied for low-elbow systems, is not required. For a 25 MV beam, EPID PDIs and ionization chamber measurements in the EPID detector plane were obtained behind an anthropomorphic phantom and a homogeneous absorber for various field shapes. The difference in absolute dose between the EPID and ionization chamber measurements, averaged over the four test fields presented in this paper, was 0.1 +/- 0.5% (1 SD) over the entire irradiation field, with no deviation larger than 2%.

Measuring portal dose with an electronic portal imaging device (EPID) in external beam radiotherapy can be used to perform routine dosimetric quality control checks on linear accelerators and to verify treatments (in vivo dosimetry). An accurate method to measure portal dose images (PDIs) with a commercially available fluoroscopic EPID has been developed. The method accounts for (i) the optical 'cross talk' within the EPID structure, (ii) the spatially nonuniform EPID response and (iii) the nonlinearity of the EPID response. The method is based on a deconvolution algorithm. Measurement of the required input data is straightforward. The observed nonlinearity of the EPID response was largely due to the somewhat outdated EPID electronics. Nonlinearity corrections for more modern systems are expected to be smaller. The accuracy of the method was assessed by comparing PDIs measured with the EPID with PDIs measured with a scanning ionization chamber in a miniphantom, located at the same position as the fluorescent screen. For irradiations in open, wedged and intensity modulated 25 MV photon beams (produced with dynamic multileaf collimation) EPID and ionization chamber measurements agreed to within 1% (1 SD).

An electronic portal imaging device (EPID) for use in radiotherapy with high energy photons has been under development since 1985 and has been in clinical use since 1988. The x-ray detector consists of a metal plate/fluorescent screen combination, which is monitored by a charge-coupled device (CDD)-camera. This paper discusses the physical quantities governing image quality. A model which describes the signal and noise propagation through the detector is presented. The predicted contrasts and signal-to-noise ratios are found to be in agreement with measurements based on the EPID images. Based on this agreement the visibility of low contrast structures in clinical images has been calculated with the model. Sufficient visibility of relevant structures (4-10 mm water-equivalent thickness) has been obtained down to a delivered dose of 4 cGy at dose maximum. It is found that the described system is not limited by quantum noise but by camera read-out noise. In addition we predict that with a new type of CCD sensor the signal-to-noise ratio can be increased by a factor of 5 at small doses, enabling high quality imaging, for most relevant clinical situations, with a patient dose smaller than 4 cGy. The latter system would be quantum noise limited.

Physical characteristics of a commercially available electronic portal imaging device (EPID), relevant to dosimetric applications in high-energy photon beams, have been investigated. The EPID basically consists of a fluorescent screen, mirrors and a CCD camera. Image acquisition for portal dose measurement has been performed with a special procedure, written in the command language that comes with the system. The observed day-to-day variation in local EPID responses, i.e. measured grey scale value (EPID signal) per unit of delivered portal dose, is 0.4% (1 SD); day-to-day variation in relative EPID responses (e.g. normalized to the on-axis response) are within 0.2% (1 SD). Measured grey scale values are linearly proportional to transmitted portal doses with a proportionality constant which is independent of the thickness of a flat, water-equivalent absorber in the beam, but which does significantly depend on the size of the applied x-ray beam. It is shown that the observed increased in EPID response with increasing field size is mainly due to contributions to the EPID signals from scattered light: visible photons produced by the x-ray beam in a point of the fluorescent screen not only generate a grey scale value in the corresponding point of the EPID image, but also lead (due to scatter from components of the EPID structure onto the CCD chip) to an increased grey scale value at all other points of the image. A point spread function, derived from measured data and describing the increase in EPID response at the beam axis due to off-axis irradiation of the fluorescent screen, has been successfully applied to connect portal doses with grey scale values measured with the EPID.

The MM50 Racetrack Microtron, suited for advanced three-dimensional conformal radiotherapy techniques, is a complex machine in various respects. Therefore, for a number of gantry angles, daily quality control of the absolute output and fluence profiles of the scanned beams are mandatory. For the applied photon beams, a fast method for these daily checks, based on dosimetric measurements with the Philips SRI-100 Electronic Portal Imaging Device (EPID), has been developed and tested. Open beams are checked for four different gantry angles; for gantry angle 0, a wedged field is checked as well. Performing and analyzing the measurements takes about 10 min. The applied EPID has favourable characteristics for dosimetric quality control measurements: absolute output measurements reproduce within 0.5% (1 SD) and the reproducibility of relative (2D) beam profile measurements is 0.2% (1 SD). The day-to-day sensitivity stability over a period of one month is 0.6% (1 SD). Measured grey scale values are within 0.2% linear with the applied dose. The 2D fluence profile of the 25 MV photon beam of the MM50 is very stable in time: during a period of 5 months a maximum fluctuation of 2.2% has been observed. Once, a deviation in the cGy/MU-value of 6% was detected. There is no interlock in the MM50-system that would have prevented patient treatment with this strongly deviating output. Based on the results of this study and on clinical requirements regarding acceptability of deviations of beam characteristics, a protocol has been developed including action levels for additional investigations and, if necessary, adjustment of the beam characteristics.