1,843 research outputs found
Laser application to measure vertical sea temperature and turbidity, design phase
An experiment to test a new method was designed, using backscattered radiation from a laser beam to measure oceanographic parameters in a fraction of a second. Tyndall, Rayleigh, Brillouin, and Raman scattering all are utilized to evaluate the parameters. A beam from a continuous argon ion laser is used together with an interferometer and interference filters to gather the information. The results are checked by direct measurements. Future shipboard and airborne experiments are described
Clinical auditing as an instrument to improve care for patients with ovarian cancer:The Dutch Gynecological Oncology Audit (DGOA)
Introduction: The Dutch Gynecological Oncology Audit (DGOA) was initiated in 2014 to serve as a nationwide audit, which registers the four most prevalent gynecological malignancies. This study presents the first results of clinical auditing for ovarian cancer in the Netherlands. Methods: The Dutch Gynecological Oncology Audit is facilitated by the Dutch Institute of Clinical Auditing (DICA) and run by a scientific committee. Items are collected through a web-based registration based on a set of predefined quality indicators. Results of quality indicators are shown, and benchmarked information is given back to the user. Data verification was done in 2016. Results: Between January 01, 2014 and December 31, 2018, 6535 patients with ovarian cancer were registered. The case ascertainment was 98.3% in 2016. The number of patients with ovarian cancer who start therapy within 28 days decreased over time from 68.7% in 2014 to 62.7% in 2018 (p < 0.001). The percentage of patients with primary cytoreductive surgery decreased over time (57.8%–39.7%, P < 0.001). However, patients with complete primary cytoreductive surgery improved over time (53.5%–69.1%, P < 0.001). Other quality indicators did not significantly change over time. Conclusion: The Dutch Gynecological Oncology Audit provides valuable data on the quality of care on patients with ovarian cancer in the Netherlands. Data show variation between hospitals with regard to pre-determined quality indicators. Results of ‘best practices’ will be shared with all participants of the clinical audit with the aim of improving quality of care nationwide
Association of vitamin B12, methylmalonic acid, and functional parameters
Introduction: Diagnosis of vitamin B12 deficiency is difficult, as there is no conclusive single test for this disorder. We evaluated the association of serum B12 and methylmalonic acid (MMA) with haematologic parameters and physical and cognitive functioning in an effort to use such clinical parameters to improve the interpretation of serum values. Methods: We used data of participants > 19 years of age from NHANES 2011-2012 and 2013-2014, a cross-sectional survey in the United States. Functional status was assessed with questionnaires on current health condition, disability, hospital utilisation, cognitive functioning, mental health and depression, and physical functioning. Muscle strength assessed with a handgrip dynamometer was used as a performance parameter. Results were evaluated both for the entire population and participants of Western European descent. Because renal function influences MMA concentrations and is a proxy for both frailty and comorbidity, all results were additionally stratified for individuals with normal vs impaired renal function (eGFR < 60 ml/min). Results: In total, data of 9645 participants (mean age 49 (SD 17) years, 49.3% males) were included. Out of all participants with serum B12 < 140, 140-300, and 301-1000 pmol/l, 56.2%, 13.5%, and 4.1%, respectively had elevated MMA. MMA concentrations were more strongly associated with poor functional status and physical performance than serum B12. We identified a significant and independent association of MMA concentrations, as well as haemoglobin and co-morbidity with muscle strength. Conclusions/interpretations: A large proportion of individuals with a decreased serum B12 concentration still has normal MMA concentrations. Elevated MMA concentrations were more strongly associated with poor functional performance than serum B12
Direct magneto-optical compression of an effusive atomic beam for high-resolution focused ion beam application
An atomic rubidium beam formed in a 70 mm long two-dimensional
magneto-optical trap (2D MOT), directly loaded from a collimated Knudsen
source, is analyzed using laser-induced fluorescence. The longitudinal velocity
distribution, the transverse temperature and the flux of the atomic beam are
reported. The equivalent transverse reduced brightness of an ion beam with
similar properties as the atomic beam is calculated because the beam is
developed to be photoionized and applied in a focused ion beam. In a single
two-dimensional magneto-optical trapping step an equivalent transverse reduced
brightness of A/(m sr eV) was
achieved with a beam flux equivalent to nA. The
temperature of the beam is further reduced with an optical molasses after the
2D MOT. This increased the equivalent brightness to A/(m sr eV). For currents below 10 pA, for which disorder-induced
heating can be suppressed, this number is also a good estimate of the ion beam
brightness that can be expected. Such an ion beam brightness would be a six
times improvement over the liquid metal ion source and could improve the
resolution in focused ion beam nanofabrication.Comment: 10 pages, 8 figures, 1 tabl
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