909 research outputs found

    The Constitution and International Agreements or Unilateral Action Curbing “Peace-Imperiling’ Propoganda

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    Non-spherical particles are present all around us, in biological, industrial and environmental processes. Making predictions of their impact on us and systems in our vicinity can make life better for everyone here on earth. For example, the ash particles from a volcano eruption are non-spherical and their spreading in the atmosphere can hugely impact the air traffic, as was also proven in 2010. Furthermore, the orientation of the wood fibres in a paper sheet influences the final properties of the paper, and the cause of a specific fibre orientation can be traced back to the fluid flows during the manufacturing process of the paper. In this thesis, experimental and numerical work is presented with the goal to understand and utilize the behavior of elongated particles in fluid flows. Two different experimental setups are used. The first one, a turbulent half channel flow, aims at increasing the understanding of how particles with non-zero inertia behave in turbulence. The second setup is an attempt to design a flow field with the purpose to align nanofibrils and create high performance cellulose filaments. Experiments were performed in a turbulent half channel flow at different flow set- tings with dilute suspensions of cellulose acetate fibres having three different aspect ratios (length to width ratio). The two main results were firstly that the fibres agglom- erated in streamwise streaks, believed to be due to the turbulent velocity structures in the flow. Secondly, the orientation of the fibres was observed to be determined by the aspect ratio and the mean shear, not the turbulence. Short fibres were oriented in the spanwise direction while long fibres were oriented in the streamwise direction. In order to utilize the impressive properties (stiffness comparable to Kevlar) of the cellulose nanofibril in a macroscopic material, the alignment of the fibrils must be controlled. Here, a flow focusing device (resulting in an extensional flow), designed to align the fibrils, is used to create a cellulose filament with aligned fibrils. The principle is based on a separation of the alignment and the assembly of the fibrils, i.e. first align the fibrils and then lock the aligned structure. With this process, continuous filaments were created, with properties similar to that of the wood fibre at the same fibril alignment. However, the highest alignment (lowest angle) of the fibrils in a filament created was only 31o from the filament axis, and the next step is to increase the alignment. This thesis includes modeling of the alignment process with the Smoluchowski equation and a rotary diffusion. Finding a model that correctly describes the alignment process should in the end make it possible to create a filament with fully aligned fibrils.QC 20140908</p

    The effect on survival of continuing chemotherapy to near death

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    <p>Abstract</p> <p>Background</p> <p>Overuse of anti-cancer therapy is an important quality-of-care issue. An aggressive approach to treatment can have negative effects on quality of life and cost, but its effect on survival is not well-defined.</p> <p>Methods</p> <p>Using the Surveillance, Epidemiology, and End Results-Medicare database, we identified 7,879 Medicare-enrolled patients aged 65 or older who died after having survived at least 3 months after diagnosis of advanced non-small cell lung cancer (NSCLC) between 1991 and 1999. We used Cox proportional hazards regression analysis, propensity scores, and instrumental variable analysis (IVA) to compare survival among patients who never received chemotherapy (n = 4,345), those who received standard chemotherapy but not within two weeks prior to death (n = 3,235), and those who were still receiving chemotherapy within 14 days of death (n = 299). Geographic variation in the application of chemotherapy was used as the instrument for IVA.</p> <p>Results</p> <p>Receipt of chemotherapy was associated with a 2-month improvement in overall survival. However, based on three different statistical approaches, no additional survival benefit was evident from continuing chemotherapy within 14 days of death. Moreover, patients receiving chemotherapy near the end of life were much less likely to enter hospice (81% versus 51% with no chemotherapy and 52% with standard chemotherapy, P < 0.001), or were more likely to be admitted within only 3 days of death.</p> <p>Conclusions</p> <p>Continuing chemotherapy for advanced NSCLC until very near death is associated with a decreased likelihood of receiving hospice care but not prolonged survival. Oncologists should strive to discontinue chemotherapy as death approaches and encourage patients to enroll in hospice for better end-of-life palliative care.</p

    The Treatment In Morning versus Evening (TIME) study:Analysis of recruitment, follow-up and retention rates post-recruitment

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    Abstract Background The use of information technology (IT) is now the preferred method of capturing and storing clinical research data. The Treatment In Morning versus Evening (TIME) study predominantly uses electronic data capture and IT to compare morning dosing of hypertensive medication against evening dosing. Registration, consent, participant demographics and follow-up data are all captured via the study website. The aim of this article is to assess the success of the TIME methodology compared with similar studies. Methods To assess the TIME study, published literature on similar clinical trials was reviewed and compared against TIME recruitment, follow-up and email interaction data. Results The TIME website registered 31,695 individuals, 21,116 of whom were randomised. Recruitment cost per randomised participant varied by strategy: £17.40 by GP practice, £3.08 by UK Biobank and £58.82 for GoShare. Twelve-month follow-up retention rates were 96%. A total of 1089 participants have withdrawn from their assigned time of dosing, 2% of whom have declined follow-up by record linkage or further contact. When the TIME data are compared with similar study data, study recruitment is very successful. However, TIME suffers difficulties with participant follow-up and withdrawal rates similar to those of conventional studies. Conclusions The TIME study has been successful in recruitment. Follow-up, retention rates and withdrawal rates are all acceptable, but ongoing work is required to ensure participants remain engaged with the study. Various recruitment strategies are necessary, and all viable options should be encouraged to maintain participant engagement throughout the life of studies using IT

    Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

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    Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

    Intended Consequences Statement in Conservation Science and Practice

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    As the biodiversity crisis accelerates, the stakes are higher for threatened plants and animals. Rebuilding the health of our planet will require addressing underlying threats at many scales, including habitat loss and climate change. Conservation interventions such as habitat protection, management, restoration, predator control, trans location, genetic rescue, and biological control have the potential to help threatened or endangered species avert extinction. These existing, well-tested methods can be complemented and augmented by more frequent and faster adoption of new technologies, such as powerful new genetic tools. In addition, synthetic biology might offer solutions to currently intractable conservation problems. We believe that conservation needs to be bold and clear-eyed in this moment of great urgency
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