On the effect of buoyancy on lateral migration of bubbles in turbulent flows insights from Direct Numerical Simulations

International audienceBubble migration is a key concern in turbulent bubbly flows as it dramatically affects momentum and mass transfers between phases. Its prediction in steam-water conditions relevant to PWR applications is difficult to assess because experiments are often conducted with air/water flows that present substantially different properties. The effect of the deformability of bubbles on the lift force has been extensively studied experimentally, or numerically, and characterized based on the Eotvos and Reynolds numbers. Nonetheless, the effect of buoyancy is not well understood. The strength of gravity and the resultant enhancement of turbulence can have a significant impact on bubble migration in the cross-flow direction.In this work, we propose to use Direct Numerical Simulations (DNS) of turbulent bubbly flows to better understand the dominant physical mechanisms at play and cover ranges of conditions difficult to access experimentally. DNS offers a rich insight into the underlying physical phenomena and allows us to control the relative importance of different sub-physics. Starting from the flow conditions studied by Lu and Tryggvason [1], we perform four DNS of bubbly flows at a slightly higher Reynolds friction number, covering deformable and almost-spherical bubbles in weakly-buoyant or buoyant conditions. Separate effects of the Eotvos number and of an increasing gravitational force are assessed. Mean quantities, Reynolds stresses and higher-order statistics are computed to analyze the effect of bubbles on liquid turbulence levels, which influences the wall-normal void fraction profile. New insights on the way bubbles alters liquid turbulence levels and influence the lateral migration of bubbles are presented. Further experimental and numerical studies are required to support and extend this analysis

Changing youth? : continuities and ruptures in transitions into adulthood among Catalan young people

The globalisation process has an impact at the micro-level on life-course patterns: concretely, the trajectories of young people into adulthood are being sharply modified. At a European level, the extension, de-linearisation, reversibility and diversification of youth trajectories have been identified as major changes. However, the extent to which these changes affect young people within each country depends on their respective welfare regimes. This article analyses how the Mediterranean welfare regime shapes youth trajectories among Catalan young people and explores the hypothesis that these constraints will make those trajectories less sensitive to the general trends of change identified at a European level. The research is based on an analysis of the Catalan Youth Survey, an official statistic that contains retrospective data on Educational, Work, Housing and Family transitions. The results offer an integrated typology of youth transitions in Catalonia and show how the persistence of traditional patterns of transition are the logical result of the particular articulation of the welfare regime and cultural patterns among Catalan young people

Human(e) rights and the cosmopolitan imagination: questions of human dignity and cultural identity

Here I seek to explore the cosmopolitan foundations of the idea of human rights. The argument begins by considering the popularity of the idea of human rights in a globalized and fast-moving commodified and digital culture. At this point I consider whether the idea of human rights might be considered to be a modern utopia similar to the role that art and nature played in the Romantic movements of the 19th century. Further, I defend human rights against those who simply see it as a form of neoliberalism or as largely ineffective against the power of the state. At this point I investigate some of the Durkheimian work within cultural sociology that has sought to investigate human rights as a form of moral community. The main problem with this view is that it has little to say about human freedom. However, viewed through a cultural lens, the global spread of human rights is connected to the idea of human dignity. While there is never likely to be a global consensus on this term, it does retain an important philosophical anchoring in Kantian ideas. More recently this debate has been revived by the critical reception of the work of Agamben and his idea of ‘bare life’. If human rights can indeed be connected to the struggle for a dignified and meaningful life, then the idea of ‘bare life’ remains an important conceptual advance. However, by considering the work and legacy of Du Bois, Gilroy and others, we can also see how the term dignity might take on other meanings in different settings. Finally, I argue that the idea of dignity and human rights could yet provide an important focus for resistance against the imperatives of capital and state in these neoliberal times

Pegfilgrastim ± ciprofloxacin for primary prophylaxis with TAC (docetaxel/doxorubicin/cyclophosphamide) chemotherapy for breast cancer. Results from the GEPARTRIO study

Background: TAC (docetaxel/doxorubicin/cyclophosphamide) is associated with high incidences of grade 4 neutropenia and febrile neutropenia (FN). This analysis compared the efficacies of four regimens for primary prophylaxis of FN and related toxic effects in breast cancer patients receiving neoadjuvant TAC. Patients and methods: Patients with stage T2-T4 primary breast cancer were scheduled to receive 6-8 cycles of TAC. Primary prophylaxis was: ciprofloxacin 500 mg orally twice daily on days 5-14 (n = 253 patients; 1478 cycles), daily granulocyte colony-stimulating factor (G-CSF) (filgrastim 5 μg/kg/day or lenograstim 150 μg/m2/day) on days 5-10 (n = 377; 2400 cycles), pegfilgrastim 6 mg on day 2 (n = 305; 1930 cycles), or pegfilgrastim plus ciprofloxacin (n = 321; 1890 cycles). Results: Pegfilgrastim with/without ciprofloxacin was significantly more effective than daily G-CSF or ciprofloxacin in preventing FN (5% and 7% versus 18% and 22% of patients; all P < 0.001), grade 4 neutropenia, and leukopenia. Pegfilgrastim plus ciprofloxacin completely prevented first cycle FN (P < 0.01 versus pegfilgrastim alone) and fatal neutropenic events. Conclusion: Ciprofloxacin alone, or daily G-CSF from day 5-10 (as in common practice), provided suboptimal protection against FN and related toxic effects in patients receiving TAC. Pegfilgrastim was significantly more effective in this setting, especially if given with ciprofloxaci

Design and rationale of a multi-center, pragmatic, open-label randomized trial of antimicrobial therapy - the study of clinical efficacy of antimicrobial therapy strategy using pragmatic design in Idiopathic Pulmonary Fibrosis (CleanUP-IPF) clinical trial

Compelling data have linked disease progression in patients with idiopathic pulmonary fibrosis (IPF) with lung dysbiosis and the resulting dysregulated local and systemic immune response. Moreover, prior therapeutic trials have suggested improved outcomes in these patients treated with either sulfamethoxazole/ trimethoprim or doxycycline. These trials have been limited by methodological concerns. This trial addresses the primary hypothesis that long-term treatment with antimicrobial therapy increases the time-to-event endpoint of respiratory hospitalization or all-cause mortality compared to usual care treatment in patients with IPF. We invoke numerous innovative features to achieve this goal, including: 1) utilizing a pragmatic randomized trial design; 2) collecting targeted biological samples to allow future exploration of 'personalized' therapy; and 3) developing a strong partnership between the NHLBI, a broad range of investigators, industry, and philanthropic organizations. The trial will randomize approximately 500 individuals in a 1:1 ratio to either antimicrobial therapy or usual care. The site principal investigator will declare their preferred initial antimicrobial treatment strategy (trimethoprim 160 mg/ sulfamethoxazole 800 mg twice a day plus folic acid 5 mg daily or doxycycline 100 mg once daily if body weight is < 50 kg or 100 mg twice daily if ≥50 kg) for the participant prior to randomization. Participants randomized to antimicrobial therapy will receive a voucher to help cover the additional prescription drug costs. Additionally, those participants will have 4-5 scheduled blood draws over the initial 24 months of therapy for safety monitoring. Blood sampling for DNA sequencing and genome wide transcriptomics will be collected before therapy. Blood sampling for transcriptomics and oral and fecal swabs for determination of the microbiome communities will be collected before and after study completion. As a pragmatic study, participants in both treatment arms will have limited in-person visits with the enrolling clinical center. Visits are limited to assessments of lung function and other clinical parameters at time points prior to randomization and at months 12, 24, and 36. All participants will be followed until the study completion for the assessment of clinical endpoints related to hospitalization and mortality events. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02759120

Outcome of ATP-based tumor chemosensitivity assay directed chemotherapy in heavily pre-treated recurrent ovarian carcinoma

BACKGROUND: We wished to evaluate the clinical response following ATP-Tumor Chemosensitivity Assay (ATP-TCA) directed salvage chemotherapy in a series of UK patients with advanced ovarian cancer. The results are compared with that of a similar assay used in a different country in terms of evaluability and clinical endpoints. METHODS: From November 1998 to November 2001, 46 patients with pre-treated, advanced ovarian cancer were given a total of 56 courses of chemotherapy based on in-vitro ATP-TCA responses obtained from fresh tumor samples or ascites. Forty-four patients were evaluable for results. Of these, 18 patients had clinically platinum resistant disease (relapse < 6 months after first course of chemotherapy). There was evidence of cisplatin resistance in 31 patients from their first ATP-TCA. Response to treatment was assessed by radiology, clinical assessment and tumor marker level (CA 125). RESULTS: The overall response rate was 59% (33/56) per course of chemotherapy, including 12 complete responses, 21 partial responses, 6 with stable disease, and 15 with progressive disease. Two patients were not evaluable for response having received just one cycle of chemotherapy: if these were excluded the response rate is 61%. Fifteen patients are still alive. Median progression free survival (PFS) was 6.6 months per course of chemotherapy; median overall survival (OAS) for each patient following the start of TCA-directed therapy was 10.4 months (95% confidence interval 7.9-12.8 months). CONCLUSION: The results show similar response rates to previous studies using ATP-TCA directed therapy in recurrent ovarian cancer. The assay shows high evaluability and this study adds weight to the reproducibility of results from different centre

Variations on the Pear Tree Experiment : different variables, new results?

Inspired by the Pear Stories Project, the Pear Tree Project has investigated how different cultures and languages describe the same film in order to apply its findings to audio description (AD). Participants from different countries were asked to "write down what they saw" in a controlled setting. This article proposes an alternative experiment, also based on the original Pear Stories Project, which aims to shed light on two issues: how different describer profiles (translation students with AD training/without AD training) and different instructions concerning the target audience profiles (blind/non-blind) could alter the final production. The results are analysed in this paper, taking into account the elements covered in the original Pear Stories Project as well as some additional elements proposed by the authors

Proteomic analysis of nipple aspirate fluid to detect biologic markers of breast cancer.

The early detection of breast cancer is the best means to minimise disease-related mortality. Current screening techniques have limited sensitivity and specificity. Breast nipple aspirate fluid can be obtained noninvasively and contains proteins secreted from ductal and lobular epithelia. Nipple aspirate fluid proteins are breast specific and generally more concentrated than corresponding blood levels. Proteomic analysis of 1 microl of diluted nipple aspirate fluid over a 5-40 kDa range from 20 subjects with breast cancer and 13 with nondiseased breasts identified five differentially expressed proteins. The most sensitive and specific proteins were 6500 and 15 940 Da, found in 75-84% of samples from women with cancer but in only 0-9% of samples from normal women. These findings suggest that (1) differential expression of nipple aspirate fluid proteins exists between women with normal and diseased breasts, and (2) analysis of these proteins may predict the presence of breast cancer