Designing all-graphene nanojunctions by covalent functionalization

We investigated theoretically the effect of covalent edge functionalization, with organic functional groups, on the electronic properties of graphene nanostructures and nano-junctions. Our analysis shows that functionalization can be designed to tune electron affinities and ionization potentials of graphene flakes, and to control the energy alignment of frontier orbitals in nanometer-wide graphene junctions. The stability of the proposed mechanism is discussed with respect to the functional groups, their number as well as the width of graphene nanostructures. The results of our work indicate that different level alignments can be obtained and engineered in order to realize stable all-graphene nanodevices

Type Ia Supernovae as Stellar Endpoints and Cosmological Tools

Empirically, Type Ia supernovae are the most useful, precise, and mature tools for determining astronomical distances. Acting as calibrated candles they revealed the presence of dark energy and are being used to measure its properties. However, the nature of the SN Ia explosion, and the progenitors involved, have remained elusive, even after seven decades of research. But now new large surveys are bringing about a paradigm shift --- we can finally compare samples of hundreds of supernovae to isolate critical variables. As a result of this, and advances in modeling, breakthroughs in understanding all aspects of SNe Ia are finally starting to happen.Comment: Invited review for Nature Communications. Final published version. Shortened, update

An algorithm to identify patients with treated type 2 diabetes using medico-administrative data

<p>Abstract</p> <p>Background</p> <p>National authorities have to follow the evolution of diabetes to implement public health policies. An algorithm was developed to identify patients with treated type 2 diabetes and estimate its annual prevalence in Luxembourg using health insurance claims when no diagnosis code is available.</p> <p>Methods</p> <p>The DIABECOLUX algorithm was based on patients' age as well as type and number of hypoglycemic agents reimbursed between 1995 and 2006. Algorithm validation was performed using the results of a national study based on medical data. Sensitivity, specificity and predictive values were estimated.</p> <p>Results</p> <p>The sensitivity of the DIABECOLUX algorithm was found superior to 98.2%. Between 2000 and 2006, 22,178 patients were treated for diabetes in Luxembourg, among whom 21,068 for type 2 diabetes (95%). The prevalence was estimated at 3.79% in 2006 and followed an increasing linear trend during the period. In 2005, the prevalence was low for young age classes and increased rapidly from 40 to 70 for male and 80 for female, reaching a peak of, respectively 17.0% and 14.3% before decreasing.</p> <p>Conclusions</p> <p>The DIABECOLUX algorithm is relevant to identify treated type 2 diabetes patients. It is reproducible and should be transferable to every country using medico-administrative databases not including diagnosis codes. Although undiagnosed patients and others with lifestyle recommendations only were not considered in this study, this algorithm is a cheap and easy-to-use tool to inform health authorities. Further studies will use this tool with the aim of improving the quality of health care dedicated to diabetic patients in Luxembourg.</p

Assessing quality of care for the dying from the bereaved relatives’ perspective: using pre-testing survey methods across seven countries to develop an international outcome measure

Background: The provision of care for dying cancer patients varies on a global basis. In order to improve care, we need to be able to evaluate the current level of care. One method of assessment is to use the views from the bereaved relatives. Aim: The aim of this study is to translate and pre-test the ‘Care Of the Dying Evaluation’ (CODETM) questionnaire across seven participating countries prior to conducting an evaluation of current quality of care. Design: The three stages were as follows: (1) translation of CODE in keeping with standardised international principles; (2) pre-testing using patient and public involvement and cognitive interviews with bereaved relatives; and (3) utilising a modified nominal group technique to establish a common, core international version of CODE. Setting/participants: Hospital settings: for each country, at least five patient and public involvement representatives, selected by purposive sampling, fed back on CODETM questionnaire; and at least five bereaved relatives to cancer patients undertook cognitive interviews. Feedback was collated and categorised into themes relating to clarity, recall, sensitivity and response options. Structured consensus meeting held to determine content of international CODE (i-CODE) questionnaire. Results: In total, 48 patient and public involvement representatives and 35 bereaved relatives contributed to the pre-testing stages. No specific question item was recommended for exclusion from CODETM. Revisions to the demographic section were needed to be culturally appropriate. Conclusion: Patient and public involvement and bereaved relatives’ perceptions helped enhance the face and content validity of i-CODE. A common, core international questionnaire is now developed with key questions relating to quality of care for the dying