Systems engineering framework for railway control & safety systems

Traditional railway signalling systems have been based on fixed block train separation and line-of-sight signals to control the movement of trains. This has historically led to a segregation of both the functionality and the development of sub-systems such as signalling, rolling stock and control centres, all following a sequential design-based approach in their development. These traditional systems are becoming increasingly redundant as the railway industry embraces modern systems such as the higher levels of ERTMS and CBTC. With the change to these complex systems of systems also comes a change in the way in which the industry must develop and deliver projects. The railway industry has, at times, struggled to embrace systems engineering, as it is perceived to run against the safety-focused design approach that rightfully enjoys a high status within the industry. Many engineers in the industry who are familiar with the traditional design based approach also struggle with relating the new systems to the traditional principles that they are used to. This research investigates the feasibility of producing a systems engineering framework that can be applied to all forms of Railway Control & Safety (RCS) systems in order to simplify their development and delivery

Oral squamous cell carcinoma proliferative phenotype is modulated by proanthocyanidins: a potential prevention and treatment alternative for oral cancer

<p>Abstract</p> <p>Background</p> <p>Despite the recently reported drop in the overall death rate from cancer, the estimated survival rate and number of deaths from oral cancer remain virtually unchanged. Early detection efforts, in combination with strategies for prevention and risk-reduction, have the potential to dramatically improve clinical outcomes. The identification of non-toxic, effective treatments, including complementary and alternative therapies, is critical if the survival rate is to be improved. Epidemiologic studies have suggested a protective effect from certain plant-derived foods and extracts; however, it has been difficult to isolate and identify the compounds most responsible for these observations. The primary purpose of this study was to investigate the response of human oral squamous cell carcinoma (OSCC) to proanthocyanidin (PAC), a plant-derived compound that may inhibit the progression of several other cancers.</p> <p>Methods</p> <p>Using a series of <it>in vitro </it>assays, we sought to quantify the effects of PAC on OSCC, cervical carcinoma, and non-cancerous cell lines, specifically the effects of PAC on cell proliferation. Recent data suggest that infection with the human papillomavirus (HPV) may also modulate the proliferative potential of OSCC; therefore, we also measured the effects of PAC administration on HPV-transfected OSCC proliferation.</p> <p>Results</p> <p>Our results demonstrated that PAC administration was sufficient to significantly suppress cellular proliferation of OSCC in a dose-dependent manner. In addition, the increased proliferation of OSCC after transfection with HPV 16 was reduced by the administration of PAC, as was the proliferation of the cervical cancer and non-cancerous cell lines tested. Our results also provide preliminary evidence that PAC administration may induce apoptosis in cervical and oral cancer cell lines, while acting merely to suppress proliferation of the normal cell line control.</p> <p>Conclusion</p> <p>These results signify that PAC may be a compelling candidate for testing in both animal and human models. Furthermore, these data provide adequate justification for elucidating the divergent mechanisms of PAC-induced proliferation, inhibition, and apoptosis among these and other cell lines.</p

The influence of a family program on adolescent tobacco and alcohol use

Objectives. This study examined a family-directed program's effectiveness in preventing adolescent tobacco and alcohol use in a general population. Methods. Adolescents aged 12 to 14 years and their families were identified by random-digit dialing throughout the contiguous United States. After providing baseline data by telephone interviews, they were randomly allocated to receive or not receive a family-directed program featuring mailed booklets and telephone contacts by health educators. Follow-up telephone interviews were conducted 3 and 12 months after program completion. Results. The findings suggested that smoking onset was reduced by 16.4% at 1 year, with a 25.0% reduction for non-Hispanic Whites but no statistically significant program effect for other races/ ethnicities. There were no statistically significant program effects for smokeless tobacco or alcohol use onset. Conclusions. The family-directed program was associated with reduced smoking onset for non-Hispanic Whites, suggesting that it is worthy of further application, development, and evaluation

The WiggleZ Dark Energy Survey: Direct constraints on blue galaxy intrinsic alignments at intermediate redshifts

Correlations between the intrinsic shapes of galaxy pairs, and between the intrinsic shapes of galaxies and the large-scale density field, may be induced by tidal fields. These correlations, which have been detected at low redshifts (z<0.35) for bright red galaxies in the Sloan Digital Sky Survey (SDSS), and for which upper limits exist for blue galaxies at z~0.1, provide a window into galaxy formation and evolution, and are also an important contaminant for current and future weak lensing surveys. Measurements of these alignments at intermediate redshifts (z~0.6) that are more relevant for cosmic shear observations are very important for understanding the origin and redshift evolution of these alignments, and for minimising their impact on weak lensing measurements. We present the first such intermediate-redshift measurement for blue galaxies, using galaxy shape measurements from SDSS and spectroscopic redshifts from the WiggleZ Dark Energy Survey. Our null detection allows us to place upper limits on the contamination of weak lensing measurements by blue galaxy intrinsic alignments that, for the first time, do not require significant model-dependent extrapolation from the z~0.1 SDSS observations. Also, combining the SDSS and WiggleZ constraints gives us a long redshift baseline with which to constrain intrinsic alignment models and contamination of the cosmic shear power spectrum. Assuming that the alignments can be explained by linear alignment with the smoothed local density field, we find that a measurement of \sigma_8 in a blue-galaxy dominated, CFHTLS-like survey would be contaminated by at most +/-0.02 (95% confidence level, SDSS and WiggleZ) or +/-0.03 (WiggleZ alone) due to intrinsic alignments. [Abridged]Comment: 18 pages, 12 figures, accepted to MNRAS; v2 has correction to one author's name, NO other changes; v3 has minor changes in explanation and calculations, no significant difference in results or conclusions; v4 has an additional footnote about model interpretation, no changes to data/calculations/result

The Reflection Component from Cygnus X-1 in the Soft State Measured by NuSTAR and Suzaku

The black hole binary Cygnus X-1 was observed in late 2012 with the Nuclear Spectroscopic Telescope Array (NuSTAR) and Suzaku, providing spectral coverage over the ~1-300 keV range. The source was in the soft state with a multi-temperature blackbody, power law, and reflection components along with absorption from highly ionized material in the system. The high throughput of NuSTAR allows for a very high quality measurement of the complex iron line region as well as the rest of the reflection component. The iron line is clearly broadened and is well described by a relativistic blurring model, providing an opportunity to constrain the black hole spin. Although the spin constraint depends somewhat on which continuum model is used, we obtain ɑ_* > 0.83 for all models that provide a good description of the spectrum. However, none of our spectral fits give a disk inclination that is consistent with the most recently reported binary values for Cyg X-1. This may indicate that there is a >13° misalignment between the orbital plane and the inner accretion disk (i.e., a warped accretion disk) or that there is missing physics in the spectral models

Mass drug administration of ivermectin, diethylcarbamazine, plus albendazole compared with diethylcarbamazine plus albendazole for reduction of lymphatic filariasis endemicity in Papua New Guinea: a cluster-randomised trial

Background: A single co-administered dose of a triple-drug regimen (ivermectin, diethylcarbamazine, and albendazole) has been shown to be safe and more efficacious for clearing Wuchereria bancrofti microfilariae than the standard two-drug regimen of diethylcarbamazine plus albendazole in clinical trials. However, the effectiveness of mass drug administration with the triple-drug regimen compared with the two-drug regimen is unknown. We compared the effectiveness of mass drug administration with the triple-drug and two-drug regimens for reducing microfilariae prevalence to less than 1% and circulating filarial antigen prevalence to less than 2%, levels that are unlikely to sustain transmission of lymphatic filariasis, in Papua New Guinea. Methods: This open-label, cluster-randomised study was done in 24 villages in a district endemic for lymphatic filariasis in Papua New Guinea. Villages paired by population size were randomly assigned to receive mass drug administration with a single dose of the triple-drug oral regimen of ivermectin (200 μg per kg of bodyweight) plus diethylcarbamazine (6 mg per kg of bodyweight) plus albendazole (400 mg) or a single dose of the two-drug oral regimen of diethylcarbamazine (6 mg per kg of bodyweight) plus albendazole (400 mg). This is a follow-on study of a previously reported safety study (ClinicalTrials.gov NCT02899936). All residents aged 5 years or older and non-pregnant women were asked to participate. After cross-sectional night blood microfilariae and circulating filarial antigen surveys, mass drug administration was provided at baseline and repeated 12 months later. The primary outcomes were mean prevalence of microfilariae and circulating filarial antigen at 12 months and 24 months, assessed in all residents willing to participate at each timepoint. This study is registered with ClinicalTrials.gov, NCT03352206. Findings: Between Nov 18, 2016, and May 26, 2017, 4563 individuals were enrolled in 24 clusters; 12 clusters (2382 participants) were assigned to the triple-drug regimen and 12 clusters (2181 participants) to the two-drug regimen. Mean drug ingestion rates (of residents aged ≥5 years) were 66·1% at baseline and 63·2% at 12 months in communities assigned to the triple-drug regimen and 65·9% at baseline and 54·9% at 12 months in communities assigned to the two-drug regimen. Microfilariae prevalence in the triple-drug regimen group decreased from 105 (4·4%) of 2382 participants (95% CI 3·6–5·3) at baseline to nine (0·4%) of 2319 (0·1–0·7) at 12 months and four (0·2%) of 2086 (0·1–0·5) at 24 months. In the two-drug regimen group, microfilariae prevalence decreased from 93 (4·3%) of 2181 participants (95% CI 3·5–5·2) at baseline to 29 (1·5%) of 1963 (1·0–2·1) at 12 months and eight (0·4%) of 1844 (0·2–0·9) at 24 months (adjusted estimated risk ratio 4·5, 95% CI 1·4–13·8, p=0·0087, at 12 months; 2·9, 95% CI 1·0–8·8, p=0·058, at 24 months). The prevalence of circulating filarial antigen decreased from 523 (22·0%) of 2382 participants (95% CI 20·3–23·6) at baseline to 378 (16·3%) of 2319 (14·9–17·9) at 12 months and 156 (7·5%) of 2086 (6·4–8·7) at 24 months in the triple-drug regimen group and from 489 (22·6%) of 2168 participants (20·7–24·2) at baseline to 358 (18·2%) of 1963 (16·7–20·1) at 12 months and 184 (10·0%) of 1840 (8·7–11·5) at 24 months in the two-drug regimen group; after adjustment, differences between groups were not significant. Interpretation: Mass administration of the triple-drug regimen was more effective than the two-drug regimen in reducing microfilariae prevalence in communities to less than the target level of 1%, but did not reduce circulating filarial antigen prevalence to less than 2%. These results support the use of mass drug administration with the triple-drug regimen to accelerate elimination of lymphatic filariasis

Microfoundations

The paper argues that the microfoundations programme can be understood as an implementation of an underlying methodological principle, methodological individualism, and that it therefore shares a fundamental ambiguity with that principle, viz, whether the macro must be derived from and therefore reducible to, or rather consistent with micro-level behaviours. The pluralist conclusion of the paper is not that research guided by the principle of microfoundations is necessarily wrong, but that the exclusion of approaches not guided by that principle is indeed necessarily wrong. The argument is made via an examination of the advantages claimed for dynamic stochastic general equilibrium models, the relationship between parts and wholes in social science, and the concepts of reduction, substrate neutrality, the intentional stance, and hypostatisation

Microfoundations

This paper argues that the microfoundations programme can be understood as an implementation of an underlying methodological principle—methodological individualism—and that it therefore shares a fundamental ambiguity with that principle, viz, whether the macro must be derived from and therefore reducible to, or rather consistent with, micro-level behaviours. The pluralist conclusion of the paper is not that research guided by the principle of microfoundations is necessarily wrong, but that the exclusion of approaches not guided by that principle is indeed necessarily wrong. The argument is made via an examination of the advantages claimed for dynamic stochastic general equilibrium models, the relationship between parts and wholes in social science, and the concepts of reduction, substrate neutrality, the intentional stance, and hypostatisation

The NuSTAR ULX program

We present the results of the first large program of broadband ULX observations with NuSTAR, XMM-Newton and Suzaku, yielding high-quality spectra and timing measurements from 0.3-30 keV in 6 ULXs, providing powerful information for understanding the accretion modes and nature of the central BHs. In particular, we find that all ULXs in our sample have a clear cutoff above 10 keV. This cutoff is less pronounced than expected by Comptonization from a cold, thick corona. We confirm the presence of a soft excess at low energies in the brightest ULXs, with temperatures below ~ 0.5 keV. We make an estimates on the masses of several ULXs based on spectral variability and model fitting

Schools and skills of critical thinking for urban design

© 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group. This paper explores possible ways in which urban design can engage with critical thinking and critical theory. After a brief explanation of the terms, with particular attention to the Frankfurt School of thought, it provides various answers to the question as to whether urban design is critical or not. One categorization applied to planning critical theory is then used to explain the potential for employing critical theories in urban design. Critical thinking skills are then argued to be helpful for enriching the literature of urban design in order to achieve better practice. The conclusion is that urban design can benefit from critical creativity, which is an embodiment of critical thinking within the limits imposed onto creativity. In this paper, the ways in which urban design can engage with both critical theory and with critical thinking are explored in order to achieve better critical creativity in the field