Orbiter/launch system

The system includes reusable turbojet propelled booster vehicles releasably connected to a reusable rocket powered orbit vehicle. The coupled orbiter-booster combination takes off horizontally and ascends to staging altitude and speed under booster power with both orbiter and booster wings providing lift. After staging, the booster vehicles fly back to Earth for horizontal landing and the orbiter vehicle continues ascending to orbit

Multi-Player Diffusion Games on Graph Classes

We study competitive diffusion games on graphs introduced by Alon et al. [1] to model the spread of influence in social networks. Extending results of Roshanbin [8] for two players, we investigate the existence of pure Nash equilibria for at least three players on different classes of graphs including paths, cycles, grid graphs and hypercubes; as a main contribution, we answer an open question proving that there is no Nash equilibrium for three players on (m x n) grids with min(m, n) >= 5. Further, extending results of Etesami and Basar [3] for two players, we prove the existence of pure Nash equilibria for four players on every d-dimensional hypercube.Comment: Extended version of the TAMC 2015 conference version now discussing hypercube results (added details for the proof of Proposition 1

Research priorities for irrigation management in Asia An overview of research in irrigation management in Asia

Irrigation management / Research / Asia

Results of an aqueous source term model for a radiological risk assessment of the Drigg LLW Site, U.K.

A radionuclide source term model has been developed which simulates the biogeochemical evolution of the Drigg low level waste (LLW) disposal site. The DRINK (DRIgg Near field Kinetic) model provides data regarding radionuclide concentrations in groundwater over a period of 100,000 years, which are used as input to assessment calculations for a groundwater pathway. The DRINK model also provides input to human intrusion and gaseous assessment calculations through simulation of the solid radionuclide inventory. These calculations are being used to support the Drigg post closure safety case. The DRINK model considers the coupled interaction of the effects of fluid flow, microbiology, corrosion, chemical reaction, sorption and radioactive decay. It represents the first direct use of a mechanistic reaction-transport model in risk assessment calculations

Constraint-Induced aphasia therapy: Three single case studies.

TITLE OF POSTER: CONSTRAINT INDUCED APHASIA THERAPY - THREE SINGLE CASE STUDIES INTRODUCTION This research project was inspired by the Specific Interest Group in Aphasia study day given by Professor Pulvermuller in January 2011. Constraint Induced Aphasia Therapy (CIAT) is sometimes referred to as Intensive Language Action Therapy (ILAT). This technique has an impressive research base to support its use for people with aphasia (PWA) and the evidence base includes both single case and randomised control trial evidence (Pulvermuller, Neininger, Elbert, Mohr, Rockstroh, Koebbl & Taub, 2001). Pulvermuller et al (2001) describe CIAT as a game of pairs. The game is normally played by four players: a therapist and three PWA. A 32 pack of cards consisting of 16 pairs is shuffled and divided equally between the four players. No one can see anyone else’s cards. The aim of the game is to win the most pairs of cards. Clients can win a pair by asking each of the other players in turn, for a matching card. All requests and responses should be verbal but participants may describe the target word or use a gesture in order to achieve saying the word. An essential part of the game is that each player should see and hear the name of the card in play. RESEARCH METHOD Three PWA were prioritised from a typical general hospital SLT caseload. All three clients were one to two years post onset of their aphasia and had already been provided with impairment focussed, functional and psychosocial SLT input. They had moderate to severe aphasia, had difficulties at several levels of single word processing and frequently failed to convey their message despite having a degree of linguistic competence and an ability to use alternative communication strategies. Accessible formal assessment measures (Kaplan, Goodglass & Weintraub 1983, Goodglass, Kaplan & Barresi 2000 & Swinburn, Porter & Howard 2004) were used to evaluate the success of therapy in a four step repeated measures research design: Baseline 1, 30 hours CIAT therapy, Baseline 2, Baseline 3. SUMMARY OF RESULTS For 2/3 clients, assessment results suggested that participation in the CIAT programme resulted in a positive measurable change in language behaviour. This positive change was not apparent in assessments of understanding. Selective improvement of language ability suggests that the therapy directed at language output had resulted in improved word and sentence level skills for 2/3 of our clients. There were also positive changes that were not captured by the assessment data: reduced use of written and therapist cues, improved repetition skills, improved self-monitoring and a reduced tendency to produce jargon type utterances. Relatives corroborated therapist perceptions. CONCLUSIONS In 2006 Beeson & Robey (2006, p162) proposed that rehabilitation outcome research should be conducted in five phases. Our study is one of the first to provide evidence to support the use of intensive CIAT therapy in the community (phase 4 – an effectiveness study). Other studies have assessed the usefulness of the therapeutic effect of ILAT (phase 1), optimised the ILAT procedure (phase 2) and tested its usefulness under ideal conditions (phase 3). The final phase outlined by Beeson & Robey (2006) is the cost-benefit analysis (phase 5) and we would welcome debate within the profession on improving this type of input and the role of Speech and Language Therapists in intensive aphasia therapy provision. REFERENCES Pulvermuller, F., Neininger, B., Elbert, T., Mohr, B., Rockstroh, B., Koebbl,P. & Taub, E. (2001) Constraint induced therapy for chronic aphasia after stroke. Stroke, 1621-1626. Beeson, P. M. & Robey, R.R. (2006) Evaluating single-subject treatment research: Lessons learnt from the aphasia literature. Neuropsychological Review, 16, 161-169. KAPLAN, E., GOODGLASS, H. and WEINTRAUB, S. (1983) The Boston Naming Test. Philadelphia: Lea and Febiger. Goodglass, H., Kaplan, E. & Barresi, B. (2000) Boston Diagnostic Aphasia Examination. 3rd Edition. San Antonio: Pearson. Swinburn, K., Porter, G., & Howard, D. (2004). The Comprehensive Aphasia Test. Hove: Psychology Press

Optimal MRI sequences for 68Ga-PSMA-11 PET/MRI in evaluation of biochemically recurrent prostate cancer.

BackgroundPET/MRI can be used for the detection of disease in biochemical recurrence (BCR) patients imaged with 68Ga-PSMA-11 PET. This study was designed to determine the optimal MRI sequences to localize positive findings on 68Ga-PSMA-11 PET of patients with BCR after definitive therapy. Fifty-five consecutive prostate cancer patients with BCR imaged with 68Ga-PSMA-11 3.0T PET/MRI were retrospectively analyzed. Mean PSA was 7.9 ± 12.9 ng/ml, and mean PSA doubling time was 7.1 ± 6.6 months. Detection rates of anatomic correlates for prostate-specific membrane antigen (PSMA)-positive foci were evaluated on small field of view (FOV) T2, T1 post-contrast, and diffusion-weighted images. For prostate bed recurrences, the detection rate of dynamic contrast-enhanced (DCE) imaging for PSMA-positive foci was evaluated. Finally, the detection sensitivity for PSMA-avid foci on 3- and 8-min PET acquisitions was compared.ResultsPSMA-positive foci were detected in 89.1% (49/55) of patients evaluated. Small FOV T2 performed best for lymph nodes and detected correlates for all PSMA-avid lymph nodes. DCE imaging performed the best for suspected prostate bed recurrence, detecting correlates for 87.5% (14/16) of PSMA-positive prostate bed foci. The 8-min PET acquisition performed better than the 3-min acquisition for lymph nodes smaller than 1 cm, detecting 100% (57/57) of lymph nodes less than 1 cm, compared to 78.9% (45/57) for the 3-min acquisition.ConclusionPSMA PET/MRI performed well for the detection of sites of suspected recurrent disease in patients with BCR. Of the MRI sequences obtained for localization, small FOV T2 images detected the greatest proportion of PSMA-positive abdominopelvic lymph nodes and DCE imaging detected the greatest proportion of PSMA-positive prostate bed foci. The 8-min PET acquisition was superior to the 3 min acquisition for detection of small lymph nodes

Preoperative neutrophil-lymphocyte ratio and outcome from coronary artery bypass grafting

Background: An elevated preoperative white blood cell count has been associated with a worse outcome after coronary artery bypass grafting (CABG). Leukocyte subtypes, and particularly the neutrophil-lymphocyte (N/L) ratio, may however, convey superior prognostic information. We hypothesized that the N/L ratio would predict the outcome of patients undergoing surgical revascularization. Methods: Baseline clinical details were obtained prospectively in 1938 patients undergoing CABG. The differential leukocyte was measured before surgery, and patients were followed-up 3.6 years later. The primary end point was all-cause mortality. Results: The preoperative N/L ratio was a powerful univariable predictor of mortality (hazard ratio [HR] 1.13 per unit, P 3.36). Conclusion: An elevated N/L ratio is associated with a poorer survival after CABG. This prognostic utility is independent of other recognized risk factors.Peer reviewedAuthor versio

Quasar Luminosity Functions from Joint Evolution of Black Holes and Host Galaxies

We show that our previously proposed anti-hierarchical baryon collapse scenario for the joint evolution of black holes and host galaxies predicts quasar luminosity functions at redshifts 1.5<z<6 and local properties in nice agreement with observations. In our model the quasar activity marks and originates the transition between an earlier phase of violent and heavily dust-enshrouded starburst activity promoting rapid black hole growth, and a later phase of almost passive evolution; the former is traced by the submillimeter-selected sources, while the latter accounts for the high number density of massive galaxies at substantial redshifts z>1.5, the population of Extremely Red Objects, and the properties of local ellipticals.Comment: 15 pages, 8 figures, uses REVTeX 4 + emulateapj.cls and apjfonts.sty. Version revised following referee's comments. Accepted on Ap

R-Estimates vs. GMM: A Theoretical Case Study of Validity and Efficiency

What role should assumptions play in inference? We present a small theoretical case study of a simple, clean case, namely the nonparametric comparison of two continuous distributions using (essentially) information about quartiles, that is, the central information displayed in a pair of boxplots. In particular, we contrast a suggestion of John Tukey—that the validity of inferences should not depend on assumptions, but assumptions have a role in efficiency—with a competing suggestion that is an aspect of Hansen’s generalized method of moments—that methods should achieve maximum asymptotic efficiency with fewer assumptions. In our case study, the practical performance of these two suggestions is strikingly different. An aspect of this comparison concerns the unification or separation of the tasks of estimation assuming a model and testing the fit of that model. We also look at a method (MERT) that aims not at best performance, but rather at achieving reasonable performance across a set of plausible models