228 research outputs found

    Quantitative imaging of the complexity in liquid bubbles' evolution reveals the dynamics of film retraction

    Get PDF
    The dynamics and stability of thin liquid films have fascinated scientists over many decades. Thin film flows are central to numerous areas of engineering, geophysics, and biophysics and occur over a wide range of length, velocity, and liquid properties scales. In spite of many significant developments in this area, we still lack appropriate quantitative experimental tools with the spatial and temporal resolution necessary for a comprehensive study of film evolution. We propose tackling this problem with a holographic technique that combines quantitative phase imaging with a custom setup designed to form and manipulate bubbles. The results, gathered on a model aqueous polymeric solution, provide an unparalleled insight into bubble dynamics through the combination of full-field thickness estimation, three-dimensional imaging, and fast acquisition time. The unprecedented level of detail offered by the proposed methodology will promote a deeper understanding of the underlying physics of thin film dynamics

    A microcapillary rheometer for microliter sized polymer characterization

    Get PDF
    Abstract We report the design of a microcapillary rheometer (μCR) that allows to perform experiments rapidly and in a broad range of shear rates (i.e., from 0.1 to 1000 s−1), using small amounts of material (i.e., just few milligrams). Additionally, multiple measurement parallelization makes it suitable for High-Throughput Rheological Experimentation of polymer melts (HT-Rheo-E). The novel rheometer consists of a set of three cylindrical microcapillaries in which the fluid flows driven by a controlled pressure. A camera, placed at the capillary exit, records the fluid motion to measure its flow rate, from which the fluid viscosity can be determined. The optimization of the setup allowed for reliable and fast viscosity measurements using ca. 10 mg of material. The current work reports the design of the rheometer and validation measurements on several model fluids. The microfabricated μCR is of potential interest for applications in quality control and research where rapid and repeated measurements using limited milligrams of polymer are required, as well as for High-Throughput-Experimentation of complex fluids (e.g., biological systems)

    Quantitative imaging of the complexity in liquid bubbles’ evolution reveals the dynamics of film retraction

    Get PDF
    Thin liquid films: Seeing bubbles in a better light A procedure for imaging the complex fluid dynamics in bubbles could greatly assist efforts to understand and exploit thin liquid films in applications ranging through medicine, industrial chemistry and engineering. Thin liquid films are ubiquitous in nature, found in such varied systems as soap bubbles, biological membranes, detergents, oils, insulation, foods and geological magma. Researchers in Italy led by Biagio Mandracchia at the Institute of Applied Science and Intelligent Systems in Naples, devised a novel holographic phase imaging technique to watch bubbles as they form, develop, burst and retract. The researchers built customized apparatus to create and manipulate the bubbles. The unprecedented level of detail being revealed offers deeper understanding of the physics underlying thin film behavior. Insights into the complex fluid dynamics within bubbles could advance thin film technology for many applications

    Investigar en Trabajo Social: diferentes experiencias como pasantes de investigación

    Get PDF
    El presente trabajo se propone compartir tres experiencias de investigación llevadas a cabo por estudiantes (ahora licenciadas) en la Facultad de Trabajo Social de la Universidad Nacional de La Plata, en diferentes proyectos de investigación. Dos de las experiencias de pasantías se enmarcaron en el proyecto de investigación “Seguridad, Violencia y Derechos Humanos. Un estudio de las representaciones sociales en jóvenes y policías”1. La otra pasantía se inserta en el proyecto “Disputas en el espacio público: cultura, política y desigualdades socio-urbanas”2. A su vez, dos de nosotras continuamos nuestro proceso de aprendizaje del oficio de investigar a través de dos becas CIN en el marco de los proyectos de investigación acreditados, mencionados anteriormente. Haremos una breve mención respecto a esto. Por último, analizaremos las experiencias como pasantes de investigación a la luz de los aportes de distintos autores/as, haciendo hincapié principalmente en la comprensión de las competencias, habilidades y destrezas necesarias para desarrollar la práctica investigativa.Eje Teórico-metodológico en Trabajo Social-GT 27: Metodología y Trabajo Social.Facultad de Trabajo Socia

    INfluenza Vaccine Indication During therapy with Immune checkpoint inhibitors: a transversal challenge. The INVIDIa study

    Get PDF
    Aim: Considering the unmet need for the counseling of cancer patients treated with immune checkpoint inhibitors (CKI) about influenza vaccination, an explorative study was planned to assess flu vaccine efficacy in this population. Methods: INVIDIa was a retrospective, multicenter study, enrolling consecutive advanced cancer outpatients receiving CKI during the influenza season 2016-2017. Results: Of 300 patients, 79 received flu vaccine. The incidence of influenza syndrome was 24.1% among vaccinated, versus 11.8% of controls; odds ratio: 2.4; 95% CI: 1.23-4.59; p = 0.009. The clinical ineffectiveness of vaccine was more pronounced among elderly: 37.8% among vaccinated patients, versus 6.1% of unvaccinated, odds ratio: 9.28; 95% CI: 2.77-31.14; p < 0.0001. Conclusion: Although influenza vaccine may be clinically ineffective in advanced cancer patients receiving CKI, it seems not to negatively impact the efficacy of anticancer therapy

    Dupilumab in the treatment of severe uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP): A multicentric observational Phase IV real-life study (DUPIREAL)

    Get PDF
    Background Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with significant morbidity and reduced health-related quality of life. Findings from clinical trials have demonstrated the effectiveness of dupilumab in CRSwNP, although real-world evidence is still limited. Methods This Phase IV real-life, observational, multicenter study assessed the effectiveness and safety of dupilumab in patients with severe uncontrolled CRSwNP (n = 648) over the first year of treatment. We collected data at baseline and after 1, 3, 6, 9, and 12 months of follow-up. We focused on nasal polyps score (NPS), symptoms, and olfactory function. We stratified outcomes by comorbidities, previous surgery, and adherence to intranasal corticosteroids, and examined the success rates based on current guidelines, as well as potential predictors of response at each timepoint. Results We observed a significant decrease in NPS from a median value of 6 (IQR 5–6) at baseline to 1.0 (IQR 0.0–2.0) at 12 months (p < .001), and a significant decrease in Sino-Nasal Outcomes Test-22 (SNOT-22) from a median score of 58 (IQR 49–70) at baseline to 11 (IQR 6–21; p < .001) at 12 months. Sniffin' Sticks scores showed a significant increase over 12 months (p < .001) compared to baseline. The results were unaffected by concomitant diseases, number of previous surgeries, and adherence to topical steroids, except for minor differences in rapidity of action. An excellent-moderate response was observed in 96.9% of patients at 12 months based on EPOS 2020 criteria. Conclusions Our findings from this large-scale real-life study support the effectiveness of dupilumab as an add-on therapy in patients with severe uncontrolled CRSwNP in reducing polyp size and improving the quality of life, severity of symptoms, nasal congestion, and smell

    Clinical features and outcomes of elderly hospitalised patients with chronic obstructive pulmonary disease, heart failure or both

    Get PDF
    Background and objective: Chronic obstructive pulmonary disease (COPD) and heart failure (HF) mutually increase the risk of being present in the same patient, especially if older. Whether or not this coexistence may be associated with a worse prognosis is debated. Therefore, employing data derived from the REPOSI register, we evaluated the clinical features and outcomes in a population of elderly patients admitted to internal medicine wards and having COPD, HF or COPD + HF. Methods: We measured socio-demographic and anthropometric characteristics, severity and prevalence of comorbidities, clinical and laboratory features during hospitalization, mood disorders, functional independence, drug prescriptions and discharge destination. The primary study outcome was the risk of death. Results: We considered 2,343 elderly hospitalized patients (median age 81 years), of whom 1,154 (49%) had COPD, 813 (35%) HF, and 376 (16%) COPD + HF. Patients with COPD + HF had different characteristics than those with COPD or HF, such as a higher prevalence of previous hospitalizations, comorbidities (especially chronic kidney disease), higher respiratory rate at admission and number of prescribed drugs. Patients with COPD + HF (hazard ratio HR 1.74, 95% confidence intervals CI 1.16-2.61) and patients with dementia (HR 1.75, 95% CI 1.06-2.90) had a higher risk of death at one year. The Kaplan-Meier curves showed a higher mortality risk in the group of patients with COPD + HF for all causes (p = 0.010), respiratory causes (p = 0.006), cardiovascular causes (p = 0.046) and respiratory plus cardiovascular causes (p = 0.009). Conclusion: In this real-life cohort of hospitalized elderly patients, the coexistence of COPD and HF significantly worsened prognosis at one year. This finding may help to better define the care needs of this population

    Clinical features and outcomes of elderly hospitalised patients with chronic obstructive pulmonary disease, heart failure or both

    Get PDF
    Background and objective: Chronic obstructive pulmonary disease (COPD) and heart failure (HF) mutually increase the risk of being present in the same patient, especially if older. Whether or not this coexistence may be associated with a worse prognosis is debated. Therefore, employing data derived from the REPOSI register, we evaluated the clinical features and outcomes in a population of elderly patients admitted to internal medicine wards and having COPD, HF or COPD + HF. Methods: We measured socio-demographic and anthropometric characteristics, severity and prevalence of comorbidities, clinical and laboratory features during hospitalization, mood disorders, functional independence, drug prescriptions and discharge destination. The primary study outcome was the risk of death. Results: We considered 2,343 elderly hospitalized patients (median age 81 years), of whom 1,154 (49%) had COPD, 813 (35%) HF, and 376 (16%) COPD + HF. Patients with COPD + HF had different characteristics than those with COPD or HF, such as a higher prevalence of previous hospitalizations, comorbidities (especially chronic kidney disease), higher respiratory rate at admission and number of prescribed drugs. Patients with COPD + HF (hazard ratio HR 1.74, 95% confidence intervals CI 1.16-2.61) and patients with dementia (HR 1.75, 95% CI 1.06-2.90) had a higher risk of death at one year. The Kaplan-Meier curves showed a higher mortality risk in the group of patients with COPD + HF for all causes (p = 0.010), respiratory causes (p = 0.006), cardiovascular causes (p = 0.046) and respiratory plus cardiovascular causes (p = 0.009). Conclusion: In this real-life cohort of hospitalized elderly patients, the coexistence of COPD and HF significantly worsened prognosis at one year. This finding may help to better define the care needs of this population
    corecore