Spatially resolved high resolution x-ray spectroscopy for magnetically confined fusion plasmas (invited)

The use of high resolution x-ray crystal spectrometers to diagnose fusion plasmas has been limited by the poor spatial localization associated with chord integrated measurements. Taking advantage of a new x-ray imaging spectrometer concept [M. Bitter et al., Rev. Sci. Instrum. 75, 3660 (2004)], and improvements in x-ray detector technology [Ch. Broennimann et al., J. Synchrotron Radiat. 13, 120 (2006)], a spatially resolving high resolution x-ray spectrometer has been built and installed on the Alcator C-Mod tokamak. This instrument utilizes a spherically bent quartz crystal and a set of two dimensional x-ray detectors arranged in the Johann configuration [H. H. Johann, Z. Phys. 69, 185 (1931)] to image the entire plasma cross section with a spatial resolution of about 1 cm. The spectrometer was designed to measure line emission from H-like and He-like argon in the wavelength range 3.7 and 4.0 A with a resolving power of approximately 10,000 at frame rates up to 200 Hz. Using spectral tomographic techniques [I. Condrea, Phys. Plasmas 11, 2427 (2004)] the line integrated spectra can be inverted to infer profiles of impurity emissivity, velocity, and temperature. From these quantities it is then possible to calculate impurity density and electron temperature profiles. An overview of the instrument, analysis techniques, and example profiles are presented.

Wide-angle point-to-point x-ray imaging with almost arbitrarily large angles of incidence

The paper describes a new scheme for wide-angle point-to-point x-ray imaging with almost arbitrarily large angles of incidence by a matched pair of spherically bent crystals to eliminate the astigmatism, which is a well-known imaging error of spherical mirrors. In addition to x rays, the scheme should be applicable to a very broad spectrum of the electromagnetic radiation, including microwaves, infrared and visible light, as well as UV and extreme UV radiation, if the crystals are replaced with appropriate spherical reflectors. The scheme may also be applicable to the imaging with ultrasound.

Dissociated functional brain abnormalities of inhibition in boys with pure conduct disorder and in boys with pure attention deficit hyperactivity disorder

OBJECTIVE

Inhibitory dysfunction may be a transdiagnostic etiopathophysiology of disruptive behavior disorders. Functional magnetic resonance imaging (fMRI) of inhibitory control has only been investigated in patients with attention deficit hyperactivity disorder (ADHD), including comorbidity with conduct disorder, showing frontal-striatal dysfunction. This study investigates differences and commonalities in functional neural networks mediating inhibitory control between medication-naive adolescents with pure conduct disorder and those with pure ADHD to identify biological markers that distinguish these clinically overlapping disorders.

METHOD

Event-related fMRI was used to compare brain activation of 13 boys with noncomorbid conduct disorder, 20 with noncomorbid ADHD, and 20 normal boys during an individually adjusted tracking stop task that measures the neural substrates of inhibition and stopping failure.

RESULTS

During successful inhibition, only patients with ADHD showed reduced activation in the left dorsolateral prefrontal cortex in relation to comparison subjects and patients with conduct disorder. During inhibition failures compared to go responses, both patient groups shared underactivation in the posterior cingulate gyrus in relation to comparison subjects. Patients with conduct disorder showed reduced activation in bilateral temporal-parietal regions compared to the other groups, which did not differ in this measure.

CONCLUSIONS

Patients with pure ADHD or pure conduct disorder show qualitative differences in their brain abnormality patterns during inhibitory control. Inhibition-mediating prefrontal regions appear to be specifically reduced in ADHD, whereas posterior temporal-parietal, performance monitoring networks are specifically dysfunctional in conduct disorder. The findings provide pioneering evidence that distinct neurobiological abnormalities may be underlying the overlapping behavioral phenotype of the two disruptive disorders.

Glucose-stimulated increment in oxygen consumption rate as a standardized test of human islet quality

Standardized assessment of islet quality is imperative for clinical islet transplantation. We have previously shown that the increment in oxygen consumption rate stimulated by glucose (DeltaOCR(glc)) can predict in vivo efficacy of islet transplantation in mice. To further evaluate the approach, we studied three factors: islet specificity, islet composition and agreement between results obtained by different groups. Equivalent perifusion systems were set up at the City of Hope and the University of Washington and the values of DeltaOCR(glc) obtained at both institutions were compared. Islet specificity was determined by comparing DeltaOCR(glc) in islet and nonislet tissue. The DeltaOCR(glc) ranged from 0.01 to 0.19 nmol/min/100 islets (n = 14), a wide range in islet quality, but the values obtained by the two centers were similar. The contribution from nonislet impurities was negligible (DeltaOCR(glc) was 0.12 nmol/min/100 islets vs. 0.007 nmol/min/100 nonislet clusters). The DeltaOCR(glc) was statistically independent of percent beta cells, demonstrating that DeltaOCR(glc) is governed more by islet quality than by islet composition. The DeltaOCR(glc), but not the absolute level of OCR, was predictive of reversal of hyperglycemia in diabetic mice. These demonstrations lay the foundation for testing DeltaOCR(glc) as a measurement of islet quality for human islet transplantation.

Educational quality improvement report: outcomes from a revised morbidity and mortality format that emphasised patient safety

PROBLEM

Although morbidity and mortality conferences (MMCs) are meant to promote quality care through careful analysis of adverse events, focus on individual actions or the fear of incrimination may interfere with identification of system issues contributing to the adverse outcomes.

DESIGN

Participant attitudes before and after the intervention towards patient safety and conference redesign were assessed using an attitudinal survey. A list of contributing factors, recommended solutions and targeted system improvements was maintained with ongoing progress recorded.

SETTING

Department of Internal Medicine training programme at University of Missouri-Columbia.

PARTICIPANTS

Residents and fellows from the above residency programme.

EDUCATIONAL OBJECTIVES

(1) Distinguish between culture of blame/shame and patient safety culture, (2) identify gaps in quality contributing to adverse outcomes (3) identify strategies to close gaps and (4) participate in root cause analysis, demonstrating an ability to review an adverse event and recommend an action plan.

STRATEGIES FOR CHANGE

An interdisciplinary team modified the internal medicine MMC to emphasise a better understanding of patient safety principles and system-based practice interventions. For each adverse event analysed, root causes were identified, followed by discussion of system interventions that might prevent future such events.

KEY MEASURES FOR IMPROVEMENT

(1) Attitudes of residents and fellows regarding patient safety, as measured on a 20-item, five-point ordinal scale survey, (2) system improvements generated from the patient safety MMC (PSMMC) and (3) attendance at PSMMC.

EFFECTS OF CHANGE

Clinical outcomes: 121 system improvement recommendations were made and 39 were pursued on the basis of likelihood of achieving high impact changes. 23 improvements were implemented, 11 were partially implemented or in progress, and 5 were abandoned due to impracticality or redundancy. Educational outcomes: 58 residents and fellows completed surveys before and after modification of conference format. 6/20 survey items showed substantial change with four of these changes occurring in the desired direction. Eleven of the remaining 14 responses changed in the desired direction. Average MMC attendance increased from 41+/-8 to 50+/-10 participants (p<0.03).

LESSONS LEARNT

The new PSMMC initiated multiple improvements in the quality of patient care without sacrificing attendance or attitudes of the residents or fellows. The new PSMMC promotes opportunities for participants to improve quality of patient care in a safe and nurturing environment.

The key role of nutrition in controlling human population dynamics

The early hominids and their successors, the nomadic hunter–gatherers, were evolutionarily adapted to an omnivorous diet. Their food was well balanced nutritionally and they acquired adequate supplies with relatively little expenditure of energy. The complete change to a fixed agricultural lifestyle (the Neolithic revolution) took place only some 12 000 years ago and was the most momentous event in human history. Being tied to the land that they worked led eventually to the city states and the great civilisations of history, which brought with them wars and epidemics of infectious diseases. Much more serious were the insidious effects of the new cereal-based diet which persisted until the twentieth century. Not only was it labour intensive, but also for the bulk of the population it was often deficient in vitamins, minerals and energy, particularly at certain times of the year. Time-series analysis reveals a regular short wavelength oscillation in the grain supply that persisted for at least 350 years and dominated the population dynamics of pre-industrial England. In addition to reducing fertility, it acted primarily via its effects on the nutrition of the pregnant woman. Malnutrition during one of the critical trimesters of pregnancy could have far-reaching effects not only on the health of the fetus and neonate but also on the illnesses of later, adult life. These consequences were insidiously and inevitably carried forward to the subsequent generations. Girls who were born with a low birth weight produced daughters and granddaughters of low birth weight, irrespective of their nutrition during childhood. These intergenerational, knock-on effects established a vicious circle from which there was little chance of escape.

Safety, feasibility and weight loss after transoral gastroplasty: First human multicenter study

OBJECTIVE

To evaluate the safety and feasibility in human subjects of a new transoral restrictive procedure for the treatment of obesity.

METHODS

The protocol was approved by the institutional review boards (IRBs) of both centers involved, and all patients gave informed consent. Patients met established inclusion criteria for bariatric surgery. The TOGa system (Satiety Inc., Palo Alto, CA), a set of transoral endoscopically guided staplers, was used to create a stapled restrictive pouch along the lesser curve of the stomach. Patients were hospitalized overnight for observation and underwent barium upper gastrointestinal (UGI) the next morning. Post procedure, all patients were placed on a liquid diet for 1 month and asked to begin an exercise program. Follow-up was carried out at 1 week and 1, 3, 4, 5, and 6 months.

RESULTS

Twenty one patients were enrolled [17 female, age 43.7 (22-57) years, BMI 43.3 (35-53) kg/m(2)]. Device introduction was completed safely in all patients. There were no serious adverse events (AEs). The most commonly reported procedure or device related adverse events were vomiting, pain, nausea, and transient dysphagia. At 6 month endoscopy, all patients had persistent full or partial stapled sleeves. Gaps in the staple line were evident in 13 patients. Patients lost an average 17.6 pounds at 1 month, 24.5 pounds at three months, and 26.5 pounds at 6 months post-treatment [excess weight loss (EWL) of 16.2%, 22.6%, and 24.4%, respectively].

CONCLUSIONS

There is great interest in new procedures for morbid obesity that could offer lower morbidity than current options. Early experience with the TOGa procedure indicates that this transoral approach may be safe and feasible. Further experience with the device and technique should improve anatomic and functional outcomes in the future. Additional studies are underway.

Use of the clock-drawing test in a hospice population

BACKGROUND

Cognitive impairment is common in patients with advanced disease and has significant implications for the patient, their carers and hospice staff. The effectiveness of screening tools is limited by a number of factors. The clock-drawing test (CDT) has performed well in other settings but has rarely been studied in the hospice setting.

AIM

To assess the performance of the CDT in a hospice population.

METHODS

Consecutive admissions to a large hospice over three months were assessed using the CDT, the abbreviated mental test score and brief tests of attention and memory function.

RESULTS

One-hundred and nine eligible patients were admitted and 77% took part. Thirty per cent were cognitively impaired. The CDT had a sensitivity of 0.92, a specificity of 0.73 and a negative predictive value of 0.95. No patient refused to complete it.

CONCLUSIONS

The CDT performs well as a screening tool for cognitive impairment in a hospice population.

Impact of a theoretically based sex education programme (SHARE) delivered by teachers on NHS registered conceptions and terminations: final results of cluster randomised trial

OBJECTIVE

To assess the impact of a theoretically based sex education programme (SHARE) delivered by teachers compared with conventional education in terms of conceptions and terminations registered by the NHS.

DESIGN

Follow-up of cluster randomised trial 4.5 years after intervention.

SETTING

NHS records of women who had attended 25 secondary schools in east Scotland.

PARTICIPANTS

4196 women (99.5% of those eligible).

INTERVENTION

SHARE programme (intervention group) v existing sex education (control group).

MAIN OUTCOME MEASURE

NHS recorded conceptions and terminations for the achieved sample linked at age 20.

RESULTS

In an "intention to treat" analysis there were no significant differences between the groups in registered conceptions per 1000 pupils (300 SHARE v 274 control; difference 26, 95% confidence interval -33 to 86) and terminations per 1000 pupils (127 v 112; difference 15, -13 to 42) between ages 16 and 20.

CONCLUSIONS

This specially designed sex education programme did not reduce conceptions or terminations by age 20 compared with conventional provision. The lack of effect was not due to quality of delivery. Enhancing teacher led school sex education beyond conventional provision in eastern Scotland is unlikely to reduce terminations in teenagers.

TRIAL REGISTRATION

ISRCTN48719575 [controlled-trials.com].

Mutations in WNT7A cause a range of limb malformations, including Fuhrmann syndrome and Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome

Fuhrmann syndrome and the Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome are considered to be distinct limb-malformation disorders characterized by various degrees of limb aplasia/hypoplasia and joint dysplasia in humans. In families with these syndromes, we found homozygous missense mutations in the dorsoventral-patterning gene WNT7A and confirmed their functional significance in retroviral-mediated transfection of chicken mesenchyme cell cultures and developing limbs. The results suggest that a partial loss of WNT7A function causes Fuhrmann syndrome (and a phenotype similar to mouse Wnt7a knockout), whereas the more-severe limb truncation phenotypes observed in Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome result from null mutations (and cause a phenotype similar to mouse Shh knockout). These findings illustrate the specific and conserved importance of WNT7A in multiple aspects of vertebrate limb development.