110 research outputs found

    Pre-Excitation Studies for Rubidium-Plasma Generation

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    The key element in the Proton-Driven-Plasma-Wake-Field-Accelerator (AWAKE) project is the generation of highly uniform plasma from Rubidium vapor. The standard way to achieve full ionization is to use high power laser which can assure the over-barrier-ionization (OBI) along the 10 meters long active region. The Wigner-team in Budapest is investigating an alternative way of uniform plasma generation. The proposed Resonance Enhanced Multi Photon Ionization (REMPI) scheme probably can be realized by much less laser power. In the following the resonant pre-excitations of the Rb atoms are investigated, theoretically and the status report about the preparatory work on the experiment are presented.Comment: 8 pages, 6 figures, submitted to Nucl. Inst. and Meth. in Phys. Res.

    Development of electricity consumption profiles of residential buildings based on smart meter data clustering

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    In the present research, a high-resolution, detailed electric load dataset was assessed, collected by smart meters from nearly a thousand households in Hungary, many of them single-family houses. The objective was to evaluate this database in detail to determine energy consumption profiles from time series of daily and annual electric load. After representativity check of dataset daily and annual energy consumption profiles were developed, applying three different clustering methods (k-means, fuzzy k-means, agglomerative hierarchical) and three different cluster validity indexes (elbow method, silhouette method, Dunn index) in MATLAB environment. The best clustering method for our examination proved to be the kmeans clustering technique. Analyses were carried out to identify different consumer groups, as well as to clarify the impact of specific parameters such as meter type in the housing unit (e.g. peak, offpeak meter), day of the week (e.g. weekend, weekday), seasonality, geographical location, settlement type and housing type (single-family house, flat, age class of the building). Furthermore, four electric user profile types were proposed, which can be used for building energy demand simulation, summer heat load and winter heating demand calculatio

    Erythropoietin receptor expression is a potential prognostic factor in human lung adenocarcinoma

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    Recombinant human erythropoietins (rHuEPOs) are used to treat cancer-related anemia. Recent preclinical studies and clinical trials, however, have raised concerns about the potential tumor-promoting effects of these drugs. Because the clinical significance of erythropoietin receptor (EPOR) signaling in human non-small cell lung cancer (NSCLC) also remains controversial, our aim was to study whether EPO treatment modifies tumor growth and if EPOR expression has an impact on the clinical behavior of this malignancy. A total of 43 patients with stage III-IV adenocarcinoma (ADC) and complete clinicopathological data were included. EPOR expression in human ADC samples and cell lines was measured by quantitative real-time polymerase chain reaction. Effects of exogenous rHuEPOalpha were studied on human lung ADC cell lines in vitro. In vivo growth of human ADC xenografts treated with rHuEPOalpha with or without chemotherapy was also assessed. In vivo tumor and endothelial cell (EC) proliferation was determined by 5-bromo-2'-deoxy-uridine (BrdU) incorporation and immunofluorescent labeling. Although EPOR mRNA was expressed in all of the three investigated ADC cell lines, rHuEPOalpha treatment (either alone or in combination with gemcitabine) did not alter ADC cell proliferation in vitro. However, rHuEPOalpha significantly decreased tumor cell proliferation and growth of human H1975 lung ADC xenografts. At the same time, rHuEPOalpha treatment of H1975 tumors resulted in accelerated tumor endothelial cell proliferation. Moreover, in patients with advanced stage lung ADC, high intratumoral EPOR mRNA levels were associated with significantly increased overall survival. This study reveals high EPOR level as a potential novel positive prognostic marker in human lung ADC

    Ki67 index is an independent prognostic factor in epithelioid but not in non-epithelioid malignant pleural mesothelioma: a multicenter study

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    BACKGROUND: Estimating the prognosis in malignant pleural mesothelioma (MPM) remains challenging. Thus, the prognostic relevance of Ki67 was studied in MPM. METHODS: Ki67 index was determined in a test cohort of 187 cases from three centres. The percentage of Ki67-positive tumour cells was correlated with clinical variables and overall survival (OS). The prognostic power of Ki67 index was compared with other prognostic factors and re-evaluated in an independent cohort (n=98). RESULTS: Patients with Ki67 higher than median (>15%) had significantly (P<0.001) shorter median OS (7.5 months) than those with low Ki67 (19.1 months). After multivariate survival analyses, Ki67 proved to be-beside histology and treatment-an independent prognostic marker in MPM (hazard ratio (HR): 2.1, P<0.001). Interestingly, Ki67 was prognostic exclusively in epithelioid (P<0.001) but not in non-epithelioid subtype. Furthermore, Ki67 index was significantly lower in post-chemotherapy samples when compared with chemo-naive cases. The prognostic power was comparable to other recently published prognostic factors (CRP, fibrinogen, neutrophil-to-leukocyte ratio (NLR) and nuclear grading score) and was recapitulated in the validation cohort (P=0.048). CONCLUSION: This multicentre study demonstrates that Ki67 is an independent and reproducible prognostic factor in epithelioid but not in non-epithelioid MPM and suggests that induction chemotherapy decreases the proliferative capacity of MPM

    30 years of collaboration

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    We highlight some of the most important cornerstones of the long standing and very fruitful collaboration of the Austrian Diophantine Number Theory research group and the Number Theory and Cryptography School of Debrecen. However, we do not plan to be complete in any sense but give some interesting data and selected results that we find particularly nice. At the end we focus on two topics in more details, namely a problem that origins from a conjecture of Rényi and Erdős (on the number of terms of the square of a polynomial) and another one that origins from a question of Zelinsky (on the unit sum number problem). This paper evolved from a plenary invited talk that the authors gaveat the Joint Austrian-Hungarian Mathematical Conference 2015, August 25-27, 2015 in Győr (Hungary)

    How do 66 European institutional review boards approve one protocol for an international prospective observational study on traumatic brain injury? Experiences from the CENTER-TBI study

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    Background The European Union (EU) aims to optimize patient protection and efficiency of health-care research by harmonizing procedures across Member States. Nonetheless, further improvements are required to increase multicenter research efficiency. We investigated IRB procedures in a large prospective European multicenter study on traumatic brain injury (TBI), aiming to inform and stimulate initiatives to improve efficiency. Methods We reviewed relevant documents regarding IRB submission and IRB approval from European neurotrauma centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI). Documents included detailed information on IRB procedures and the duration from IRB submission until approval(s). They were translated and analyzed to determine the level of harmonization of IRB procedures within Europe. Results From 18 countries, 66 centers provided the requested documents. The primary IRB review was conducted centrally (N = 11, 61%) or locally (N = 7, 39%) and primary IRB approval was obtained after one (N = 8, 44%), two (N = 6, 33%) or three (N = 4, 23%) review rounds with a median duration of respectively 50 and 98 days until primary IRB approval. Additional IRB approval was required in 55% of countries and could increase duration to 535 days. Total duration from submission until required IRB approval was obtained was 114 days (IQR 75-224) and appeared to be shorter after submission to local IRBs compared to central IRBs (50 vs. 138 days, p = 0.0074). Conclusion We found variation in IRB procedures between and within European countries. There were differences in submission and approval requirements, number of review rounds and total duration. Research collaborations could benefit from the implementation of more uniform legislation and regulation while acknowledging local cultural habits and moral values between countries.Peer reviewe

    Predictors of Access to Rehabilitation in the Year Following Traumatic Brain Injury : A European Prospective and Multicenter Study

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    Background Although rehabilitation is beneficial for individuals with traumatic brain injury (TBI), a significant proportion of them do not receive adequate rehabilitation after acute care. Objective Therefore, the goal of this prospective and multicenter study was to investigate predictors of access to rehabilitation in the year following injury in patients with TBI. Methods Data from a large European study (CENTER-TBI), including TBIs of all severities between December 2014 and December 2017 were used (N = 4498 patients). Participants were dichotomized into those who had and those who did not have access to rehabilitation in the year following TBI. Potential predictors included sociodemographic factors, psychoactive substance use, preinjury medical history, injury-related factors, and factors related to medical care, complications, and discharge. Results In the year following traumatic injury, 31.4% of patients received rehabilitation services. Access to rehabilitation was positively and significantly predicted by female sex (odds ratio [OR] = 1.50), increased number of years of education completed (OR = 1.05), living in Northern (OR = 1.62; reference: Western Europe) or Southern Europe (OR = 1.74), lower prehospital Glasgow Coma Scale score (OR = 1.03), higher Injury Severity Score (OR = 1.01), intracranial (OR = 1.33) and extracranial (OR = 1.99) surgery, and extracranial complication (OR = 1.75). On contrast, significant negative predictors were lack of preinjury employment (OR = 0.80), living in Central and Eastern Europe (OR = 0.42), and admission to hospital ward (OR = 0.47; reference: admission to intensive care unit) or direct discharge from emergency room (OR = 0.24). Conclusions Based on these findings, there is an urgent need to implement national and international guidelines and strategies for access to rehabilitation after TBI.Peer reviewe

    Health-related quality of life after traumatic brain injury : deriving value sets for the QOLIBRI-OS for Italy, The Netherlands and The United Kingdom

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    Purpose The Quality of Life after Brain Injury overall scale (QOLIBRI-OS) measures health-related quality of life (HRQoL) after traumatic brain injury (TBI). The aim of this study was to derive value sets for the QOLIBRI-OS in three European countries, which will allow calculation of utility scores for TBI health states. Methods A QOLIBRI-OS value set was derived by using discrete choice experiments (DCEs) and visual analogue scales (VAS) in general population samples from the Netherlands, United Kingdom and Italy. A three-stage procedure was used: (1) A selection of health states, covering the entire spectrum of severity, was defined; (2) General population samples performed the health state valuation task using a web-based survey with three VAS questions and an at random selection of sixteen DCEs; (3) DCEs were analysed using a conditional logistic regression and were then anchored on the VAS data. Utility scores for QOLIBRI-OS health states were generated resulting in estimates for all potential health states. Results The questionnaire was completed by 13,623 respondents. The biggest weight increase for all attributes is seen from "slightly" to "not at all satisfied", resulting in the largest impact on HRQoL. "Not at all satisfied with how brain is working" should receive the greatest weight in utility calculations in all three countries. Conclusion By transforming the QOLIBRI-OS into utility scores, we enabled the application in economic evaluations and in summary measures of population health, which may be used to inform decision-makers on the best interventions and strategies for TBI patients.Peer reviewe

    Tracheal intubation in traumatic brain injury: a multicentre prospective observational study

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    Background We aimed to study the associations between pre- and in-hospital tracheal intubation and outcomes in traumatic brain injury (TBI), and whether the association varied according to injury severity. Methods Data from the international prospective pan-European cohort study, Collaborative European NeuroTrauma Effectiveness Research for TBI (CENTER-TBI), were used (n=4509). For prehospital intubation, we excluded self-presenters. For in-hospital intubation, patients whose tracheas were intubated on-scene were excluded. The association between intubation and outcome was analysed with ordinal regression with adjustment for the International Mission for Prognosis and Analysis of Clinical Trials in TBI variables and extracranial injury. We assessed whether the effect of intubation varied by injury severity by testing the added value of an interaction term with likelihood ratio tests. Results In the prehospital analysis, 890/3736 (24%) patients had their tracheas intubated at scene. In the in-hospital analysis, 460/2930 (16%) patients had their tracheas intubated in the emergency department. There was no adjusted overall effect on functional outcome of prehospital intubation (odds ratio=1.01; 95% confidence interval, 0.79–1.28; P=0.96), and the adjusted overall effect of in-hospital intubation was not significant (odds ratio=0.86; 95% confidence interval, 0.65–1.13; P=0.28). However, prehospital intubation was associated with better functional outcome in patients with higher thorax and abdominal Abbreviated Injury Scale scores (P=0.009 and P=0.02, respectively), whereas in-hospital intubation was associated with better outcome in patients with lower Glasgow Coma Scale scores (P=0.01): in-hospital intubation was associated with better functional outcome in patients with Glasgow Coma Scale scores of 10 or lower. Conclusion The benefits and harms of tracheal intubation should be carefully evaluated in patients with TBI to optimise benefit. This study suggests that extracranial injury should influence the decision in the prehospital setting, and level of consciousness in the in-hospital setting. Clinical trial registration NCT02210221

    Mutation Detection in Patients with Retinal Dystrophies Using Targeted Next Generation Sequencing

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    Retinal dystrophies (RD) constitute a group of blinding diseases that are characterized by clinical variability and pronounced genetic heterogeneity. The different nonsyndromic and syndromic forms of RD can be attributed to mutations in more than 200 genes. Consequently, next generation sequencing (NGS) technologies are among the most promising approaches to identify mutations in RD. We screened a large cohort of patients comprising 89 independent cases and families with various subforms of RD applying different NGS platforms. While mutation screening in 50 cases was performed using a RD gene capture panel, 47 cases were analyzed using whole exome sequencing. One family was analyzed using whole genome sequencing. A detection rate of 61% was achieved including mutations in 34 known and two novel RD genes. A total of 69 distinct mutations were identified, including 39 novel mutations. Notably, genetic findings in several families were not consistent with the initial clinical diagnosis. Clinical reassessment resulted in refinement of the clinical diagnosis in some of these families and confirmed the broad clinical spectrum associated with mutations in RD genes
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