Absence of the 7-repeat variant of the DRD4 VNTR is associated with drifting sustained attention in children with ADHD but not in controls

Many genetic studies have demonstrated an association between the 7-repeat (7r) allele of a 48-base pair variable number of tandem repeats (VNTR) in exon 3 of the DRD4 gene and the phenotype of attention deficit hyperactivity disorder (ADHD). Previous studies have shown inconsistent associations between the 7r allele and neurocognitive performance in children with ADHD. We investigated the performance of 128 children with and without ADHD on the Fixed and Random versions of the Sustained Attention to Response Task (SART). We employed timeseries analyses of reaction-time data to allow a fine-grained analysis of reaction time variability, a candidate endophenotype for ADHD. Children were grouped into either the 7r-present group (possessing at least one copy of the 7r allele) or the 7r-absent group. The ADHD group made significantly more commission errors and was significantly more variable in RT in terms of fast moment-to-moment variability than the control group, but no effect of genotype was found on these measures. Children with ADHD without the 7r allele made significantly more omission errors, were significantly more variable in the slow frequency domain and showed less sensitivity to the signal (d') than those children with ADHD the 7r and control children with or without the 7r. These results highlight the utility of time-series analyses of reaction time data for delineating the neuropsychological deficits associated with ADHD and the DRD4 VNTR. Absence of the 7-repeat allele in children with ADHD is associated with a neurocognitive profile of drifting sustained attention that gives rise to variable and inconsistent performance. (c) 2008 Wiley-Liss, Inc.

Dissociation in performance of children with ADHD and high-functioning autism on a task of sustained attention

Attention deficit hyperactivity disorder (ADHD) and autism are two neurodevelopmental disorders associated with prominent executive dysfunction, which may be underpinned by disruption within fronto-striatal and fronto-parietal circuits. We probed executive function in these disorders using a sustained attention task with a validated brain-behaviour basis. Twenty-three children with ADHD, 21 children with high-functioning autism (HFA) and 18 control children were tested on the Sustained Attention to Response Task (SART). In a fixed sequence version of the task, children were required to withhold their response to a predictably occurring no-go target (3) in a 1-9 digit sequence; in the random version the sequence was unpredictable. The ADHD group showed clear deficits in response inhibition and sustained attention, through higher errors of commission and omission on both SART versions. The HFA group showed no sustained attention deficits, through a normal number of omission errors on both SART versions. The HFA group showed dissociation in response inhibition performance, as indexed by commission errors. On the Fixed SART, a normal number of errors was made, however when the stimuli were randomised, the HFA group made as many commission errors as the ADHD group. Greater slow-frequency variability in response time and a slowing in mean response time by the ADHD group suggested impaired arousal processes. The ADHD group showed greater fast-frequency variability in response time, indicative of impaired top-down control, relative to the HFA and control groups. These data imply involvement of fronto-parietal attentional networks and sub-cortical arousal systems in the pathology of ADHD and prefromal cortex dysfunction in children with HFA. (c) 2007 Elsevier Ltd. All rights reserved.

Self-consistent geometry in the computation of the vibrational spectra of molecules

An exact and general approach to study molecular vibrations is provided by the Watson Hamiltonian. Within this framework, it is customary to omit the contribution of the terms with the vibrational angular momentum and the Watson term, especially for the study of large systems. We discover that this omission leads to results which depend on the choice of the reference structure. The self-consistent solution proposed here yields a geometry that coincides with the quantum averaged geometry of the Watson Hamiltonian and appears to be a promising way for the computation of the vibrational spectra of strongly anharmonic systems.

Evaluation of cement stresses in finite element analyses of cemented orthopaedic implants

Stress analysis of the cement fixation of orthopaedic implants to bone is frequently? carried out using finite element analysis. However, the stress distribution in the cement laver is usually intricate, and it is difficult to report it in a way that facilitates comparison of implants for pre-clinical testing. To study this problem, and make recommendations for stress reporting, a finite element analysis of a hip prosthesis implanted into a synthetic composite femur is developed. Three cases are analyzed: a fully bonded implant, a debonded implant, and a debonded implant where the cement is removed distal to the stein tip. In addition to peak stresses, and contour and vector plots, a stressed volume and probability-of-failure analysis is reported. It is predicted that the peak stress is highest for the debonded stem, and that removal of the distal cement more than halves this peak stress. This would suggest that omission of the distal cement is good for polished prostheses (as practiced for the Exeter design). However; if the percentage of cement stressed above a certain threshold (say 3 MPa) is considered, then the removal of distal cement is shown to be disadvantageous because a higher volume of cement is stressed to above the threshold. Vector plots clearly demonstrate the different load transfer for bonded and debonded prostheses: A bonded stein generates maximum tensile stresses in the longitudinal direction, whereas a debonded stem generates most tensile stresses in the hoop direction, except near the tip where tensile longitudinal stresses occur due to subsidence of the stein. Removal of the cement distal to the tip allows greater subsidence but alleviates these large stresses at the tip, albeit at the expense of increased hoop stresses throughout the mantle. It is concluded that a thorough analysis of cemented implants should not report peak stress, which can be misleading, but rather stressed volume, and that vector plots should be reported if a precise analysis of the load transfer mechanism is required.

Potentially inappropriate prescribing in an Irish elderly population in primary care.

AIMS Screening tools have been formulated to identify potentially inappropriate prescribing (IP) in older people. Beers’ criteria are the most widely used but have disadvantages when used in Europe. New
IP screening tools called Screening Tool of Older Person’s Prescriptions (STOPP) and Screening Tool to Alert doctors to Right Treatment (START) have been developed to identify potential IP and potential prescribing omissions (PPOs). The aim was to measure the prevalence rates of potential IP and PPOs in primary care using Beers’ criteria, STOPP and START.

METHODS
Case records of 1329 patients 65 years old from three general practices in one region of southern Ireland were studied. The mean age SD of the patients was 74.9 6.4 years, 60.9% were female. Patients’current diagnoses and prescription medicines were reviewed and the Beers’ criteria, STOPP and START tools applied.

RESULTS
The total number of medicines prescribed was 6684; median number of medicines per patient was ?ve (range 1–19). Overall, Beers’ criteria identi?ed 286 potentially inappropriate prescriptions in 18.3% (243) of patients, whilst the corresponding IP rate identi?ed by STOPP was 21.4% (284), in respect of 346 potentially inappropriate prescriptions. A total of 333 PPOs were identi?ed in 22.7% (302) of patients using the START tool.

CONCLUSION
Potentially inappropriate drug prescribing and errors of drug omission are highly prevalent among older people living in the community. Prevention strategies should involve primary care doctors and community pharmacists.

'Translated Verse': Milton's Latin Poetry in the Long Eighteenth Century

This chapter assesses ways in which the emergence in the long eighteenth century of a cluster of verse translations of Milton’s Poemata engendered an intellectual discourse and debate on translation itself, not dissimilar to the magazine warfare of the day. It argues that poetical renderings of Milton’s Latin verse, and the biographical and literary contexts in which they appeared, facilitated the interrogation of key issues that are still being debated by modern translation theorists: the nature and function of translation; the viability of rendering a source text in a target language that is also in this instance a poetic language; the potential ‘fetters’ which, in Drydenesque terms, might constrain ‘the verbal copier’; or by contrast the quasi-liberating fluency, the ‘fluent strategy’, attendant upon recourse to verse as translational medium; canonicity, amplification and omission; the much-debated issue of authorial equivalence, evinced here, it is suggested, by the editorial showcasing of the translator; and not least, the perennial question of translation as reading and critical interpretation. In short, verse renderings of Milton’s Latin poetry and the debates that they engendered assume a not inconsequential place in the history of translation theory, which, as Venuti notes, is forever concerned with ‘the changing relationships between the relative autonomy of the translated text and two other categories: equivalence and function.’

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A feasibility study testing four hypotheses with phase II outcomes in advanced colorectal cancer (MRC FOCUS3): a model for randomised controlled trials in the era of personalised medicine?

Background: Molecular characteristics of cancer vary between individuals. In future, most trials will require assessment of biomarkers to allocate patients into enriched populations in which targeted therapies are more likely to be effective. The MRC FOCUS3 trial is a feasibility study to assess key elements in the planning of such studies.

Patients and methods: Patients with advanced colorectal cancer were registered from 24 centres between February 2010 and April 2011. With their consent, patients' tumour samples were analysed for KRAS/BRAF oncogene mutation status and topoisomerase 1 (topo-1) immunohistochemistry. Patients were then classified into one of four molecular strata; within each strata patients were randomised to one of two hypothesis-driven experimental therapies or a common control arm (FOLFIRI chemotherapy). A 4-stage suite of patient information sheets (PISs) was developed to avoid patient overload.

Results: A total of 332 patients were registered, 244 randomised. Among randomised patients, biomarker results were provided within 10 working days (w.d.) in 71%, 15 w.d. in 91% and 20 w.d. in 99%. DNA mutation analysis was 100% concordant between two laboratories. Over 90% of participants reported excellent understanding of all aspects of the trial. In this randomised phase II setting, omission of irinotecan in the low topo-1 group was associated with increased response rate and addition of cetuximab in the KRAS, BRAF wild-type cohort was associated with longer progression-free survival.

Conclusions: Patient samples can be collected and analysed within workable time frames and with reproducible mutation results. Complex multi-arm designs are acceptable to patients with good PIS. Randomisation within each cohort provides outcome data that can inform clinical practice.

Victimisation and Attitudes Towards Former Political Prisoners in Northern Ireland

The release of ex-combatants and the mechanisms for their re-integration within society has become an increasingly controversial issue in peace settlements. Yet to date, the view of victims concerning such arrangements in post-conflict societies remains unexplored. Mindful of this omission and using Northern Ireland as a case study, this article investigates the relationship between victimisation and attitudes towards the treatment of former political prisoners. Based on the 2011 Northern Ireland Social and Political Attitudes Survey, the results suggest that individual victims—those who directly and/or indirectly experienced violent incidents—are notably less supportive of a punitive approach towards the treatment of former political prisoners than non-victims. Moreover, this is particularly the case when victims from within the Catholic community are considered. The Northern Ireland evidence suggests that victims can act as a positive and inclusive force in terms of the rehabilitation and re-integration of former combatants in societies emerging from conflict.

Victimhood and Attitudes towards Dealing with the Legacy of the Past: Northern Ireland as a Case Study

Research Highlights and Abstract: Using Northern Ireland as a case study, this article provides the first nationally representative and systematic study of victims' views on how to deal with the past; Focusing specifically on Northern Ireland, it both investigates and provides a comprehensive account of the marked divisions between the various religious groupings-Protestants, Catholics and the non-affiliated-in terms of a range of truth recovery mechanisms to deal with legacy of its violent past; It empirically investigates and validates two key predictors-perceptions of victimhood and general attitudes towards the past-in determining the source of these divisions It outlines the implications of our findings for other societies emerging from conflict. Truth recovery mechanisms have become a cornerstone of peacebuilding efforts in societies emerging from conflict. Yet, to date, the view of victims in post-conflict societies concerning such arrangements remains highly anecdotal and often second-hand in nature. Mindful of this omission and using Northern Ireland as a case study, this article investigates the views of victims towards a range of mechanisms to deal with the legacy of Northern Ireland's violent past. Based on the 2011 Northern Ireland Social and Political Attitudes Survey, the results suggest some marked divisions in relation to this issue, with victims within the Catholic community being significantly more supportive of such initiatives than either Protestants or those with no religion. Moreover, while perceptions of victimhood emerge as the key predictor of attitudes among Protestants and the non-affiliated, general opinions on how to deal with the past are the key determinant of views among members of the Catholic community

CLUSTER LEED - A VERY FAST METHOD FOR SURFACE-STRUCTURE DETERMINATION

A very fast method, cluster low-energy electron diffraction (LEED) is proposed for LEED I-V spectral analysis, in which three appproximations are introduced: the small-atom approximation, omission of the structure factors, and truncation of higher order ( > 2) scattering events. The method has been tested using a total of four sets of I-V spectra calculated by fully dynamic LEED for (i) the simple overlayer system, O on Ni{100}, and (ii) the reconstructed system, Cu on W{100}, and also one set of experimental data from W{100}-c(2 X 2)-Cu. In each case the correct structural parameters are recovered. It is suggested that for complex systems cluster LEED provides an efficient fast route to trial structures, which could be refined by automated tenser LEED.