822 research outputs found

    Performance of a GridPix detector based on the Timepix3 chip

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    A GridPix readout for a TPC based on the Timepix3 chip is developed for future applications at a linear collider. The GridPix detector consists of a gaseous drift volume read out by a single Timepix3 chip with an integrated amplification grid. Its performance is studied in a test beam with 2.5 GeV electrons. The GridPix detector detects single ionization electrons with high efficiency. The Timepix3 chip allowed for high sample rates and time walk corrections. Diffusion is found to be the dominating error on the track position measurement both in the pixel plane and in the drift direction, and systematic distortions in the pixel plane are below 10 μ\mum. Using a truncated sum, an energy loss (dE/dx) resolution of 4.1% is found for an effective track length of 1 m.Comment: To be published in Nuclear Instruments and Methods in Physics Research Section

    A Systematic Review of the Effects of Hyperoxia in Acutely Ill Patients:Should We Aim for Less?

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    Introduction. Despite widespread and liberal use of oxygen supplementation, guidelines about rational use of oxygen are scarce. Recent data demonstrates that current protocols lead to hyperoxemia in the majority of the patients and most health care professionals are not aware of the negative effects of hyperoxemia. Method. To investigate the effects of hyperoxemia in acutely ill patients on clinically relevant outcomes, such as neurological and functional status as well as mortality, we performed a literature review using Medline (PubMed) and Embase. We used the following terms: hyperoxemia OR hyperoxemia OR [“oxygen inhalation therapy” AND (mortality OR death OR outcome OR survival)] OR [oxygen AND (mortality OR death OR outcome OR survival)]. Original studies about the clinical effects of hyperoxemia in adult patients suffering from acute or emergency illnesses were included. Results. 37 articles were included, of which 31 could be divided into four large groups: cardiac arrest, traumatic brain injury (TBI), stroke, and sepsis. Although a single study demonstrated a transient protective effect of hyperoxemia after TBI, other studies revealed higher mortality rates after cardiac arrest, stroke, and TBI treated with oxygen supplementation leading to hyperoxemia. Approximately half of the studies showed no association between hyperoxemia and clinically relevant outcomes. Conclusion. Liberal oxygen therapy leads to hyperoxemia in a majority of patients and hyperoxemia may negatively affect survival after acute illness. As a clinical consequence, aiming for normoxemia may limit negative effects of hyperoxemia in patients with acute illness

    A prolonged ICU stay after interhospital transport?

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    Transport of critically ill patients can be complicated [1-3]. Barratt and colleagues studied patients transferred for nonclinical reasons to evaluate the consequences of transportation [4]. Th ere was no diff erence in mortality but the ICU length of stay (LOS) increased by 3  days, which was explained as a negative impact of the transport on patient physiology. We disagree with this conclusion. First, by including only transports to level 3 ICUs the received level of care for transported patients will increase, introducing a bias. Second, the increase in LOS can be interpreted as a result of selection bias, because patients with a short expected LOS would often not be considered eligible for transport. Also, since there was no increase in mortality, which would have been expected with an increased LOS, we might be looking at a mortality reduction as a result of the transfer to a higher-level ICU. Th ird, Barrett and colleagues suggest that deterioration of patient physiology during transport is probably respon sible for the increase in LOS. However, the reported Intensive Care National Audit and Research Centre scores before and after transport (although not validated for sequential patient assessments) do not support this assumption. Fourth, the method of transportation should have been included in this study. Specialised transport teams deliver patients with a better acute physiology compared with nonspecialised teams [2,5], making a need for regaining physiological stability unlikely. In conclusion, we congratulate Barratt and colleagues for their research. However, we think their conclusion is premature because multiple possible confounders were not taken into account

    Inter-hospital transport of critically ill patients; expect surprises

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    INTRODUCTION: Inter-hospital transport of critically ill patients is increasing. When performed by specialized retrieval teams there are less adverse events compared to transport by ambulance. These transports are performed with technical equipment also used in an Intensive Care Unit (ICU). As a consequence technical problems may arise and have to be dealt with on the road. In this study, all technical problems encountered while transporting patients with our mobile intensive care unit service (MICU) were evaluated. METHODS: From March 2009 until August 2011 all transports were reviewed for technical problems. The cause, solution and, where relevant, its influence on protocol were stated. RESULTS: In this period of 30 months, 353 patients were transported. In total 55 technical problems were encountered. We provide examples of how they influenced transport and how they may be resolved. CONCLUSION: The use of technical equipment is part of intensive care medicine. Wherever this kind of equipment is used, technical problems will occur. During inter-hospital transports, without extra personnel or technical assistance, the transport team is dependent on its own ability to resolve these problems. Therefore, we emphasize the importance of having some technical understanding of the equipment used and the importance of training to anticipate, prevent and resolve technical problems. Being an outstanding intensivist on the ICU does not necessarily mean being qualified for transporting the critically ill as well. Although these are lessons derived from inter-hospital transport, they may also apply to intra-hospital transport

    Nationwide evaluation of mutation-tailored treatment of gastrointestinal stromal tumors in daily clinical practice

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    Background Molecular analysis of KIT and PDGFRA is critical for tyrosine kinase inhibitor treatment selection of gastrointestinal stromal tumors (GISTs) and hence recommended by international guidelines. We performed a nationwide study into the application of predictive mutation testing in GIST patients and its impact on targeted treatment decisions in clinical practice. Methods Real-world clinical and pathology information was obtained from GIST patients with initial diagnosis in 2017-2018 through database linkage between the Netherlands Cancer Registry and the nationwide Dutch Pathology Registry. Results Predictive mutation analysis was performed in 89% of the patients with high risk or metastatic disease. Molecular testing rates were higher for patients treated in expertise centers (96%) compared to non-expertise centers (75%, P < 0.01). Imatinib therapy was applied in 81% of the patients with high risk or metastatic disease without patient's refusal or adverse characteristics, e.g., comorbidities or resistance mutations. Mutation analysis that was performed in 97% of these imatinib-treated cases, did not guarantee mutation-tailored treatment: 2% of these patients had the PDGFRA p.D842V resistance mutation and 7% initiated imatinib therapy at the normal instead of high dose despite of having a KIT exon 9 mutation. Conclusion In conclusion, nationwide real-world data show that over 81% of the eligible high risk or metastatic disease patients receive targeted therapy, which was tailored to the mutation status as recommended in guidelines in 88% of cases. Therefore, still 27% of these GIST patients misses out on mutation-tailored treatment. The reasons for suboptimal uptake of testing and treatment require further study

    Контроль выбросов вспомогательных корпусов АЭС: состояние и пути совершенствования

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    Произведен анализ состояния системы контроля выбросов через вентиляционные системы СК АЭС с ВВЭР на примере Запорожской АЭС (ЗАЭС)
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