The Depth Resolution of Secondary Ion Mass Spectrometers: A Critical Evaluation

The ability of five Secondary Ion Mass Spectrometry (SIMS) instruments to resolve thin layer and modulated dopant structures by depth profiling has been assessed. Three magnetic sector instruments (two Cameca IMS 3f\u27s and one 4f), which use optical gating and a high extraction field, were used, together with two different quadrupole based instruments (EVA 2000 and Atomika) , which use electronic gating and a low extraction field. The test structure, a thirty-one peak boron-in-silicon modulating dopant structure, was grown by Molecular Beam Epitaxy (MBE). In all the depth profiles the near surface peaks appeared narrow and asymmetric, being broadened only by fundamental processes (e.g., atomic mixing and recoil implantation). As the profiles proceeded, however, further broadening was observed. This phenomena varied markedly both from one instrument to another and from one experiment to another on the same instrument. In some cases the loss of depth resolution with depth was manifested by broadening mainly in the leading edge, in others the trailing edge, of successive boron peaks. The \u27order of merit\u27 of the instruments thus depended on the parameter used to define depth resolution. The loss of peak (depth) resolution with depth was due to variations in primary ion beam density across the gated area of the crater, which led to uneven etching. The changes in peak shape with depth can be explained by a numerical model of the etching process. These observations dictate that the depth resolution of a SIMS instrument should not be measured in terms of a single interface width, such as the leading or trailing edge

Leukotriene B4 mediates p47phox phosphorylation and membrane translocation in polyunsaturated fatty acidâ stimulated neutrophils

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142119/1/jlb0976.pd

Morphological variability in the Cuatro Cienegas cichlid, Cichlasoma minckleyi

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75338/1/j.1095-8649.2003.00006.x.pd

Values associated with public involvement in health and social care research: a narrative review

addresses: Mood Disorders Centre, Psychology, University of Exeter, Exeter, UK.OnlineOpen articleMuch has been written about public involvement (PI) in health and social care research, but underpinning values are rarely made explicit despite the potential for these to have significant influence on the practice and assessment of PI.Medical Research Council’s Methodology Research Programm

The sarcoma diagnostic interval: a systematic review on length, contributing factors and patient outcomes

Sarcomas are rare and heterogeneous mesenchymal tumours of soft tissue or bone, making them prone to late diagnosis. In other malignancies, early diagnosis has an impact on stage of disease, complexity of therapeutic procedures, survival and health-related quality of life (HRQoL). Little is known about what length of diagnostic interval should be considered as delay in patients with bone (BS) or soft tissue sarcomas (STS). To quantify total interval (defined as time from first symptom to histological diagnosis) and its components, identify contributing factors to its length and determine the impact on patients’ outcome in terms of mortality and HRQoL. A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Seventy-six articles out of 2310 met the predefined inclusion criteria. Total intervals, varied broadly; 9–120.4 weeks for BS and 4.3–614.9 weeks for STS. Older age and no initial radiological examinations were contributing factors for a long interval in BS, while in STS results were conflicting. The impact of length of total interval on clinical outcomes in terms of survival and morbidity remains ambiguous; no clear relation could be identified for both BS and STS. No study examined the impact on HRQoL. The length of total interval is variable in BS as well as STS. Its effect on outcomes is contradictory. There is no definition of a clinically relevant cut-off point that discriminates between a short or long total interval. Prospero: CRD42017062492

Effects of long-term low-dose oxygen supplementation on the epithelial function, collagen metabolism and interstitial fibrogenesis in the guinea pig lung

<p>Abstract</p> <p>Background</p> <p>The patient population receiving long-term oxygen therapy has increased with the rising morbidity of COPD. Although high-dose oxygen induces pulmonary edema and interstitial fibrosis, potential lung injury caused by long-term exposure to low-dose oxygen has not been fully analyzed. This study was designed to clarify the effects of long-term low-dose oxygen inhalation on pulmonary epithelial function, edema formation, collagen metabolism, and alveolar fibrosis.</p> <p>Methods</p> <p>Guinea pigs (n = 159) were exposed to either 21% or 40% oxygen for a maximum of 16 weeks, and to 90% oxygen for a maximum of 120 hours. Clearance of inhaled technetium-labeled diethylene triamine pentaacetate (Tc-DTPA) and bronchoalveolar lavage fluid-to-serum ratio (BAL/Serum) of albumin (ALB) were used as markers of epithelial permeability. Lung wet-to-dry weight ratio (W/D) was measured to evaluate pulmonary edema, and types I and III collagenolytic activities and hydroxyproline content in the lung were analyzed as indices of collagen metabolism. Pulmonary fibrotic state was evaluated by histological quantification of fibrous tissue area stained with aniline blue.</p> <p>Results</p> <p>The clearance of Tc-DTPA was higher with 2 week exposure to 40% oxygen, while BAL/Serum Alb and W/D did not differ between the 40% and 21% groups. In the 40% oxygen group, type I collagenolytic activities at 2 and 4 weeks and type III collagenolytic activity at 2 weeks were increased. Hydroxyproline and fibrous tissue area were also increased at 2 weeks. No discernible injury was histologically observed in the 40% group, while progressive alveolar damage was observed in the 90% group.</p> <p>Conclusion</p> <p>These results indicate that epithelial function is damaged, collagen metabolism is affected, and both breakdown of collagen fibrils and fibrogenesis are transiently induced even with low-dose 40% oxygen exposure. However, these changes are successfully compensated even with continuous exposure to low-dose oxygen. We conclude that long-term low-dose oxygen exposure does not significantly induce permanent lung injury in guinea pigs.</p

Common or multiple futures for end of life care around the world? Ideas from the ‘waiting room of history’

Around the world there is growing interest in the manner in which care is delivered to people at the end of life. However, there is little unanimity on what constitutes a ‘good death’ and the appropriate societal responses to the issue of delivering culturally relevant and sustainable forms of end of life care in different settings are not subjects of broad agreement. In this critical conceptual paper we focus on the emerging narratives of global palliative care and offer an assessment of their implications. We relate this to calls to improve end of life care across jurisdictions and settings, attempts to map and grade the development of palliative care provision, and to the emergence of a widely recognised global ‘quality of death index’. We consider an alternative approach to framing this debate, drawn from a subaltern and post-colonial studies perspective and suggest that adopting a truly global perspective will require acceptance of the plurality of past and present local problems and issues relating to end of life care, as well as the plural possibilities of how they might be overcome. In that context, we would not aim to universalise or privilege one particular global future for end of life care. Instead of homogenising end of life interventions, we seek to be open to multiple futures for the care of the dying

Risk factors and prognostic implications of diagnosis of cancer within 30 days after an emergency hospital admission (emergency presentation): an International Cancer Benchmarking Partnership (ICBP) population-based study

BACKGROUND: Greater understanding of international cancer survival differences is needed. We aimed to identify predictors and consequences of cancer diagnosis through emergency presentation in different international jurisdictions in six high-income countries. METHODS: Using a federated analysis model, in this cross-sectional population-based study, we analysed cancer registration and linked hospital admissions data from 14 jurisdictions in six countries (Australia, Canada, Denmark, New Zealand, Norway, and the UK), including patients with primary diagnosis of invasive oesophageal, stomach, colon, rectal, liver, pancreatic, lung, or ovarian cancer during study periods from Jan 1, 2012, to Dec 31, 2017. Data were collected on cancer site, age group, sex, year of diagnosis, and stage at diagnosis. Emergency presentation was defined as diagnosis of cancer within 30 days after an emergency hospital admission. Using logistic regression, we examined variables associated with emergency presentation and associations between emergency presentation and short-term mortality. We meta-analysed estimates across jurisdictions and explored jurisdiction-level associations between cancer survival and the percentage of patients diagnosed as emergencies. FINDINGS: In 857 068 patients across 14 jurisdictions, considering all of the eight cancer sites together, the percentage of diagnoses through emergency presentation ranged from 24·0% (9165 of 38 212 patients) to 42·5% (12 238 of 28 794 patients). There was consistently large variation in the percentage of emergency presentations by cancer site across jurisdictions. Pancreatic cancer diagnoses had the highest percentage of emergency presentations on average overall (46·1% [30 972 of 67 173 patients]), with the jurisdictional range being 34·1% (1083 of 3172 patients) to 60·4% (1317 of 2182 patients). Rectal cancer had the lowest percentage of emergency presentations on average overall (12·1% [10 051 of 83 325 patients]), with a jurisdictional range of 9·1% (403 of 4438 patients) to 19·8% (643 of 3247 patients). Across the jurisdictions, older age (ie, 75-84 years and 85 years or older, compared with younger patients) and advanced stage at diagnosis compared with non-advanced stage were consistently associated with increased emergency presentation risk, with the percentage of emergency presentations being highest in the oldest age group (85 years or older) for 110 (98%) of 112 jurisdiction-cancer site strata, and in the most advanced (distant spread) stage category for 98 (97%) of 101 jurisdiction-cancer site strata with available information. Across the jurisdictions, and despite heterogeneity in association size (I2=93%), emergency presenters consistently had substantially greater risk of 12-month mortality than non-emergency presenters (odds ratio >1·9 for 112 [100%] of 112 jurisdiction-cancer site strata, with the minimum lower bound of the related 95% CIs being 1·26). There were negative associations between jurisdiction-level percentage of emergency presentations and jurisdiction-level 1-year survival for colon, stomach, lung, liver, pancreatic, and ovarian cancer, with a 10% increase in percentage of emergency presentations in a jurisdiction being associated with a decrease in 1-year net survival of between 2·5% (95% CI 0·28-4·7) and 7·0% (1·2-13·0). INTERPRETATION: Internationally, notable proportions of patients with cancer are diagnosed through emergency presentation. Specific types of cancer, older age, and advanced stage at diagnosis are consistently associated with an increased risk of emergency presentation, which strongly predicts worse prognosis and probably contributes to international differences in cancer survival. Monitoring emergency presentations, and identifying and acting on contributing behavioural and health-care factors, is a global priority for cancer control. FUNDING: Canadian Partnership Against Cancer; Cancer Council Victoria; Cancer Institute New South Wales; Cancer Research UK; Danish Cancer Society; National Cancer Registry Ireland; The Cancer Society of New Zealand; National Health Service England; Norwegian Cancer Society; Public Health Agency Northern Ireland, on behalf of the Northern Ireland Cancer Registry; the Scottish Government; Western Australia Department of Health; and Wales Cancer Network