Taming hardware event samples for FDO compilation

Feedback-directed optimization (FDO) is effective in improving application runtime performance, but has not been widely adopted due to the tedious dual-compilation model, the difficulties in generating representative training data sets, and the high runtime overhead of profile collection. The use of hardware-event sampling to generate estimated edge profiles overcomes these drawbacks. Yet, hardware event samples are typically not precise at the instruction or basic-block granularity. These inaccuracies lead to missed performance when compared to instrumentation-based FDO@. In this paper, we use multiple hardware event profiles and supervised learning techniques to generate heuristics for improved precision of basic-block-level sample profiles, and to further improve the smoothing algorithms used to construct edge profiles. We demonstrate that sampling-based FDO can achieve an average of 78% of the performance gains obtained using instrumentation-based exact edge profiles for SPEC2000 benchmarks, matching or beating instrumentation-based FDO in many cases. The overhead of collection is only 0.74% on average, while compiler based instrumentation incurs 6.8%-53.5% overhead (and 10x overhead on an industrial web search application), and dynamic instrumentation incurs 28.6%-1639.2% overhead. ? 2010 ACM.EI

Non-sexist Language Policy and the Rise (and Fall?) of Combined Pronouns in British and American Written English

This paper focuses on the use of combined pronouns (s/he, his or her, him/her, etc.) as an example of late twentieth-century non-sexist language reform which had an overt democratizing aim. Within the scope of second-wave feminism, the use of combined pronouns increased the visibility of women in discourse by encouraging the use of feminine pronouns (she, her, hers) alongside masculine pronouns (he, him, his). Despite their promotion, however, the use of combined pronouns is relatively rare. This paper uses the LOB and Brown families of corpora to diachronically and synchronically study patterns in the use of combined pronouns in written American (AmE) and British English (BrE) from the 1930s to the early 2000s. The analysis not only determines what forms these patterns take, but questions whether combined pronouns are influenced by (a combination of) syntax and/or semantics, and questions whether combined pronouns are really democratic at all

Risk Owners & Risk Managers: Dealing with the complexity of feeding children with neurodevelopmental disability

This paper illustrates negotiations around risk between lay people and clinicians in relation to gastrostomy interventions for disabled children. These negotiations centre on differing interpretations of what constitutes risk in relation to the safety of oral feeding and a child's need for a feeding tube between parents, carers and clinical specialties. Drawing on Heyman's distinction between risk managers and risk owners, we show that not only do clinicians act as risk managers and parents and carers as risk owners, but that these distinctions often become blurred either because of the shifting dynamics of relations of care or because of the specificity of clinical practice. Parents become risk managers in relation to carers' roles, while clinicians become risk owners in relation to particular procedures which define their practice. This has implications for lay and expert interactions as well as professional accountability for those caring for children with complex medical conditions. Although not an empirical article, we draw on empirical work in the UK. We analyse both parental and professional constructions of risk based on observations of co-ordinating a clinical trial designed to evaluate the effectiveness of gastrostomy surgery. We also examine the diverse value systems used by different groups of professionals and lay carers which inform judgements about risk and feeding. We conclude by arguing that issues of risk in contemporary health care are not just examples of ‘manufactured uncertainty’ or of ‘negotiated power’ but constitute a dialectical relationship which breaks down the essentialist dualism of lay and professional constructions of risk

Age at onset as stratifier in idiopathic Parkinson’s disease – effect of ageing and polygenic risk score on clinical phenotypes

Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients

Clinical effectiveness of manual therapy for the management of musculoskeletal and non-musculoskeletal conditions : systematic review and update of UK evidence report

Background: This systematic review updated and extended the "UK evidence report" by Bronfort et al. (Chiropr Osteopath 18:3, 2010) with respect to conditions/interventions that received an 'inconclusive’ or 'negative’ evidence rating or were not covered in the report. Methods: A literature search of more than 10 general medical and specialised databases was conducted in August 2011 and updated in March 2013. Systematic reviews, primary comparative studies and qualitative studies of patients with musculoskeletal or non-musculoskeletal conditions treated with manual therapy and reporting clinical outcomes were included. Study quality was assessed using standardised instruments, studies were summarised, and the results were compared against the evidence ratings of Bronfort. These were either confirmed, updated, or new categories not assessed by Bronfort were added. Results: 25,539 records were found; 178 new and additional studies were identified, of which 72 were systematic reviews, 96 were randomised controlled trials, and 10 were non-randomised primary studies. Most 'inconclusive’ or 'moderate’ evidence ratings of the UK evidence report were confirmed. Evidence ratings changed in a positive direction from inconclusive to moderate evidence ratings in only three cases (manipulation/mobilisation [with exercise] for rotator cuff disorder; spinal mobilisation for cervicogenic headache; and mobilisation for miscellaneous headache). In addition, evidence was identified on a large number of non-musculoskeletal conditions not previously considered; most of this evidence was rated as inconclusive. Conclusions: Overall, there was limited high quality evidence for the effectiveness of manual therapy. Most reviewed evidence was of low to moderate quality and inconsistent due to substantial methodological and clinical diversity. Areas requiring further research are highlighted