Intractable Alcoholism in a Patient with a Levine Shunt

Ellen Shaw. M.D., Fellow in Hepatology: Mr. J is a forty-six-year-old white male who was initially seen on the medical service in July 1982. At that time he presented with hepatic encephalopathy, jaundice, and ascites. A liver biopsy was performed, confirming the clinical diagnosis of alcoholic hepatitis superimposed on cirrhosis. Following discharge it was difficult to maintain Mr. J as an outpatient. He did not follow dietary restrictions or take diuretics as prescribed. Additionally he was unable to control his drinking. Finally about a year ago a Levine shunt was implanted in an effort to control his ascites. Subsequently he did well for a period of several months. He was able to abstain from alcohol with a resulting decrease in his ascites and jaundice. Recently he has resumed drinking, with a return of his symptoms. He has missed his last several appointments in the clinic. Control of his medical problems remains problematic unless his alcohol abuse can be better controlled

Multiple electron pumping

The need to pump single electrons with a high degree of accuracy and fidelity has led to the development of a range of different pump and turnstile designs. Previous pumping mechanisms have all demonstrated that pumping more than one electron per cycle degrades the quantisation of the measured current. This unreliable delivery of multiple electrons per cycle has limited the use of on-demand single electron sources in electron quantum optic experiments. We present highly quantised current with multiple electrons pumped per cycle. We experimentally demonstrate that in our pumps an increase in electron throughput per cycle does not lead to an appreciable degradation in the accuracy of the produced current. Our pump is realised in an aluminium gallium arsenide two-dimensional electron gas, where electrons are pumped through a one-dimensional split-gate confinement potential under the influence of an applied source-drain voltage VSD , and where the pump is driven by a trapezoidal arbitrary waveform. This combination of a split-gate potential, VSD bias and trapezoidal wave form has led to the observation of robust quantised plateaus where not just a single electron, but a multiple integer number of electrons are pumped per cycle with a high degree of robustness and without the need of a magnetic field. For seven electrons per cycle, we report an increase of over two orders of magnitude in pumping accuracy from 2.72 × 10 − 2 in devices operating in the conventional pumping regime, to 1.64 × 10 − 4 in pumps operating in what we call the long plateau regime, a regime accessed under a change in a split-gate pumps applied VSD voltage. This pump will find direct use in quantum transport measurements where the metrological accuracy of single electrons pumped per cycle is not required and the low throughput per cycle of electrons is limiting

Partitioning of on-demand electron pairs

We demonstrate the high fidelity splitting of electron pairs emitted on demand from a dynamic quantum dot by an electronic beam splitter. The fidelity of pair splitting is inferred from the coincidence of arrival in two detector paths probed by a measurement of the partitioning noise. The emission characteristic of the on-demand electron source is tunable from electrons being partitioned equally and independently to electron pairs being split with a fidelity of 90%. For low beam splitter transmittance we further find evidence of pair bunching violating statistical expectations for independent fermions

Barriers to the provision of smoking cessation assistance:A qualitative study among Romanian family physicians

BACKGROUND: Smoking cessation is the most effective intervention to prevent and slow down the progression of several respiratory and other diseases and improve patient outcomes. Romania has legislation and a national tobacco control programme in line with the World Health Organization Framework for Tobacco Control. However, few smokers are advised to quit by their family physicians (FPs). AIM: To identify and explore the perceived barriers that prevent Romanian FPs from engaging in smoking cessation with patients. METHODS: A qualitative study was undertaken. A total of 41 FPs were recruited purposively from Bucharest and rural areas within 600 km of the city. Ten FPs took part in a focus group and 31 participated in semistructured interviews. Analysis was descriptive, inductive and themed, according to the barriers experienced. RESULTS: Five main barriers were identified: limited perceived role for FPs; lack of time during consultations; past experience and presence of disincentives; patients' inability to afford medication; and lack of training in smoking cessation skills. Overarching these specific barriers were key themes of a medical and societal hierarchy, which undermined the FP role, stretched resources and constrained care. CONCLUSIONS: Many of the barriers described by the Romanian FPs reflected universally recognised challenges to the provision of smoking cessation advice. The context of a relatively hierarchical health-care system and limitations of time and resources exacerbated many of the problems and created new barriers that will need to be addressed if Romania is to achieve the aims of its National Programme Against Tobacco Consumption

Towards a quantum representation of the ampere using single electron pumps

Electron pumps generate a macroscopic electric current by controlled manipulation of single electrons. Despite intensive research towards a quantum current standard over the last 25 years, making a fast and accurate quantised electron pump has proved extremely difficult. Here we demonstrate that the accuracy of a semiconductor quantum dot pump can be dramatically improved by using specially designed gate drive waveforms. Our pump can generate a current of up to 150 pA, corresponding to almost a billion electrons per second, with an experimentally demonstrated current accuracy better than 1.2 parts per million (ppm) and strong evidence, based on fitting data to a model, that the true accuracy is approaching 0.01 ppm. This type of pump is a promising candidate for further development as a realisation of the SI base unit ampere, following a re-definition of the ampere in terms of a fixed value of the elementary charge.Comment: 8 pages, 7 figure

The heteronomy of choice architecture

Choice architecture is heralded as a policy approach that does not coercively reduce freedom of choice. Still we might worry that this approach fails to respect individual choice because it subversively manipulates individuals, thus contravening their personal autonomy. In this article I address two arguments to this effect. First, I deny that choice architecture is necessarily heteronomous. I explain the reasons we have for avoiding heteronomous policy-making and offer a set of four conditions for non-heteronomy. I then provide examples of nudges that meet these conditions. I argue that these policies are capable of respecting and promoting personal autonomy, and show this claim to be true across contrasting conceptions of autonomy. Second, I deny that choice architecture is disrespectful because it is epistemically paternalistic. This critique appears to loom large even against non-heteronomous nudges. However, I argue that while some of these policies may exhibit epistemically paternalistic tendencies, these tendencies do not necessarily undermine personal autonomy. Thus, if we are to find such policies objectionable, we cannot do so on the grounds of respect for autonomy

Health service utilization in IBD: comparison of self-report and administrative data

<p>Abstract</p> <p>Background</p> <p>The reliability of self-report regarding health care utilization in inflammatory bowel disease (IBD) is unknown. If proven reliable, it could help justify self-report as a means of determining health care utilization and associated costs.</p> <p>Methods</p> <p>The Manitoba IBD Cohort Study is a population-based longitudinal study of participants diagnosed within 7 years of enrollment. Health care utilization was assessed through standardized interview. Participants (n = 352) reported the total number of nights hospitalized, frequency of physician contacts in the prior 12 months and whether the medical contacts were for IBD-related reasons or not. Reports of recent antibiotic use were also recorded. Actual utilization was drawn from the administrative database of Manitoba Health, the single comprehensive provincial health insurer.</p> <p>Results</p> <p>According to the administrative data, 15% of respondents had an overnight hospitalization, while 10% had an IBD-related hospitalization. Self-report concordance was highly sensitive (92%; 82%) and specific (96%; 97%, respectively). 97% of participants had contact with a physician in the previous year, and 69% had IBD-related visits. Physician visits were significantly under-reported and there was a trend to over-report the number of nights in hospital.</p> <p>Conclusions</p> <p>Self-report data can be helpful in evaluating health service utilization, provided that the researcher is aware of the systematic sources of bias. Outpatient visits are well identified by self-report. The discordance for the type of outpatient visit may be either a weakness of self-report or a flaw in diagnosis coding of the administrative data. If administrative data are not available, self-report information may be a cost-effective alternative, particularly for hospitalizations.</p

Cluster Lenses

Clusters of galaxies are the most recently assembled, massive, bound structures in the Universe. As predicted by General Relativity, given their masses, clusters strongly deform space-time in their vicinity. Clusters act as some of the most powerful gravitational lenses in the Universe. Light rays traversing through clusters from distant sources are hence deflected, and the resulting images of these distant objects therefore appear distorted and magnified. Lensing by clusters occurs in two regimes, each with unique observational signatures. The strong lensing regime is characterized by effects readily seen by eye, namely, the production of giant arcs, multiple-images, and arclets. The weak lensing regime is characterized by small deformations in the shapes of background galaxies only detectable statistically. Cluster lenses have been exploited successfully to address several important current questions in cosmology: (i) the study of the lens(es) - understanding cluster mass distributions and issues pertaining to cluster formation and evolution, as well as constraining the nature of dark matter; (ii) the study of the lensed objects - probing the properties of the background lensed galaxy population - which is statistically at higher redshifts and of lower intrinsic luminosity thus enabling the probing of galaxy formation at the earliest times right up to the Dark Ages; and (iii) the study of the geometry of the Universe - as the strength of lensing depends on the ratios of angular diameter distances between the lens, source and observer, lens deflections are sensitive to the value of cosmological parameters and offer a powerful geometric tool to probe Dark Energy. In this review, we present the basics of cluster lensing and provide a current status report of the field.Comment: About 120 pages - Published in Open Access at: http://www.springerlink.com/content/j183018170485723/ . arXiv admin note: text overlap with arXiv:astro-ph/0504478 and arXiv:1003.3674 by other author

Effectiveness of temozolomide for primary glioblastoma multiforme in routine clinical practice

Temozolomide has been used as a standard therapy for the treatment of newly diagnosed glioblastoma multiforme since 2005. To assess the effectiveness of temozolomide in routine clinical practice, we conducted an observational study at Maastricht University Medical Centre (MUMC). Data of patients receiving radiotherapy and temozolomide between January 2005 and January 2008 were retrieved from a clinical database (radiochemotherapy group), as were data of patients in a historical control group from the period before 2005 treated with radiotherapy only (radiotherapy group). The primary endpoint was overall survival. A total of 125 patients with GBM were selected to form the study cohort. Median survival benefit was 4 months: the median overall survival was 12 months (95% CI, 9.7–14.3) in the group with radiochemotherapy with temozolomide, versus 8 months (95% CI, 5.3–10.7) in the group with only radiotherapy. Progression-free survival was 7 months (95% CI, 5.5–8.5) in the radiochemotherapy group and 4 months (95% CI, 2.9-5.1) in the group with only radiotherapy. The two-year survival rate was 18% with radiochemotherapy with temozolomide against 4% with radiotherapy alone. Concomitant treatment with radiotherapy and temozolomide followed by adjuvant temozolomide resulted in grade III or IV haematological toxic effects in 9% of patients. The addition of temozolomide to radiotherapy in routine clinical practice for newly diagnosed glioblastoma resulted in a clinically meaningful survival benefit with minimal haematological toxicity, which confirms the experience of previous trials and justifies the continued use of temozolomide in routine clinical practice