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[en] Contraband detection systems for homeland security applications are typically tested for probability of detection (PD) and probability of false alarm (PFA) using pass-fail testing protocols. Test protocols usually require specified values for PD and PFA to be demonstrated at a specified level of statistical confidence CL. Based on a recent more theoretical treatment of this subject , this summary reviews the definition of CL and provides formulas and spreadsheet functions for constructing tables of general test requirements and for determining the minimum number of tests required. The formulas and tables in this article may be generally applied to many other applications of pass-fail testing, in addition to testing of contraband detection systems.
[en] The decision that a given detection level corresponds to the effective presence of a radionuclide is still widely made on the basis of a classic hypothesis test. However, the classic framework suffers several drawbacks, such as the conceptual and practical impossibility to provide a probability of zero radioactivity, and confidence intervals for the true activity level that are likely to contain negative and hence meaningless values. The Bayesian framework being potentially able to overcome these drawbacks, several attempts have recently been made to apply it to this decision problem. Here, we present a new Bayesian method that, unlike the previous ones, presents two major advantages together. First, it provides an estimate of the probability of no radioactivity, as well as physically meaningful point and interval estimates for the true radioactivity level. Second, whereas Bayesian approaches are often controversial because of the arbitrary choice of the priors they use, the proposed method permits to estimate the parameters of the prior density of radioactivity by fitting its marginal distribution to previously recorded activity data. The new scheme is first mathematically developed. Then, it is applied to the detection of radioxenon isotopes in noble gas measurement stations of the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty. (author)
[en] In this paper the author would like to inform about the possibilities of treatment of prostate cancer in Slovakia with a focus on radiation therapy (radiotherapy). The aim of radiotherapy is to achieve the highest concentration of radiation in the irradiated area while maximally examining the surrounding healthy tissue. Technological development and radiobiology enable the introduction of new treatments and standards in the treatment that are more effective, more gentle, and reduce the impact of healthy tissues. In the lecture, the author wants to approach contemporary modern imaging techniques such as IMRT (Intensity Modulated Radiotherapy), IGRT (Image Guided Radiotherapy) within external radiotherapy. At the same time, attention to brachytherapy, its indications, the process of application and the role in the treatment of prostate carcinoma, especially the LDR brachytherapy using iodine grains, which has been available in Slovakia since 2007. (authors)
[en] mRNAs inside cells interact with numerous RNA-binding proteins, microRNAs, and ribosomes that together compose a highly heterogeneous population of messenger ribonucleoprotein (mRNP) particles. Perhaps one of the best ways to investigate the complex regulation of mRNA is to observe individual molecules. Single molecule imaging allows the collection of quantitative and statistical data on subpopulations and transient states that are otherwise obscured by ensemble averaging. In addition, single particle tracking reveals the sequence of events that occur in the formation and remodeling of mRNPs in real time. Here, we review the current state-of-the-art techniques in tagging, delivery, and imaging to track single mRNAs in live cells. We also discuss how these techniques are applied to extract dynamic information on the transcription, transport, localization, and translation of mRNAs. These studies demonstrate how single molecule tracking is transforming the understanding of mRNA regulation in live cells. (topical review)
[en] In the present work the reaction pγ->pπ+π-π0 is analyzed with the largest statistical data available today for the W meson decay into 3 pions.The data was obtained at theThomas Jefferson National Accelerator Facility. The reaction was modeled with the production of a resonance R (pγ→ pR), followed by a decay into 3 pions (R→ π+π-π0).This decay was modeled with an Isobar, that makes it sequential in pairs (R→Iπ;Iππ). Data selection is completed and work is in progress
[en] Publishing medical papers in English is important as English remains the predominant language for most medical papers (both electronic and traditional journal publications). In addition, journals with the highest impact factors are published in English and a publication in English thus enhances the visibility of authors and their institutions, and is important for promotion in some academic centers. This article reviews the basic principles that will help you successfully publish a manuscript in English. Although other books and articles are available on this subject, there are relatively few references. The present article is based on this author's experience of publishing nearly 400 articles in English. It will emphasize writing original articles, but the principles can be applied to virtually any type of manuscript.
[en] More than 100 publications reporting radon anomalies to precede earthquakes were evaluated. A clear apparent negative correlation between the number of reported anomalies and the published length of the time-series is evident. 19% of all time-series are longer than 5 years, characterized by a precursor rate of less than one precursor per year, the extreme case being 1 anomaly in 18 years of monitoring. Contrary, precursor rates between 1 and more than 10 precursors per year stem from published time-series shorter than 3 years. Nearly 50% of the time-series contain exactly one radon anomaly, independent of the length of the observation interval. Generally, the number of anomalies is about 5 times higher at sites where radon is measured in soil air as compared to radon in groundwater. In conclusion: (i) significant radon anomalies exist, and (ii) seismo-tectonically induced radon anomalies probably exist. But, radon anomalies of non-tectonic origin also exist and may look strikingly similar to tectonic ones. Thus, presumably only a fraction of all reported radon precursors are real in the sense that they are physically related to the preparation process of an impending earthquake. (author)
[en] An effort has been made to optimally determine the status of turbulence in the present study. The parameter is identified in the framework of GA (Genetic Algorithm), which consequently resulted in the development of a computer model. In accordance with principles of the GA, the objective function, sse (sum of square of errors), is minimized between 0.009785 and 0.017565; as a result the well hydraulic parameters are optimally identified. To check validity of the model, simulated draw downs are compared against the observed ones, which indicate mean difference between them varying from 0.0049 m to 0.0124 m. Furthermore, validity of the model is also endorsed through statistical analysis with model efficiency varying between 99.97 and 100.00%. The model is applied to 5 data sets of step drawdown pumping test, yielding 5 values of turbulence coefficient varying between 1.01 and 2.08. Out of these 5 optimized values of turbulence coefficient none of the values is equal to 2. This scenario of variation of turbulence coefficient substantiate that turbulence coefficient is a variable and not a constant (i.e. equal to 2.0, as suggested by Jacob and Singh) while considering turbulence loss coefficient as a constant is discarded. (author)
[en] Cisplatin-based treatment has been considered the standard treatment regimen of HNSCC. Cetuximab is an emerging target therapy that has potential therapeutic benefits over cisplatin. Nevertheless, curative effects of cisplatin-based chemoradiotherapy (CRT) versus cetuximab-based bioradiotherapy (BRT) are still controversial. Potentially eligible studies were retrieved using PubMed, Embase and Medline. Basic characteristics of patients and statistical data were collected. A meta-analysis model was established to compare CRT and BRT. Thirty-one eligible studies and 4212 patients were found. The pooled HRs with 95 % confidence intervals (CIs) for OS and PFS were 0.32 [0.09, 0.55] and 0.51 [0.22, 0.80], respectively, and both were in favor of cisplatin. However, 3-year survival and recurrence analysis of the subgroups showed no differences between the two groups (p > 0.05). In subgroup analysis, oropharyngeal primary tumors exhibited improved results by cetuximab with a pooled HR of 1.56 [1.14, 2.13] for PFS. Additionally, the HPV+ status was a significant factor in positive outcomes with cetuximab with a pooled HR of 1.12 [0.46, 2.17] for OS. Long-term use of BRT showed no significant difference compared with CRT, and both arms showed different aspects of toxicity. In subgroup analysis, taking the effects of treatment and adverse events into consideration, cetuximab plus radiation may show superior responses regarding OS and PFS in patients who have HPV+ or primary oropharyngeal HNSCC, respectively, but physicians should administer them with caution
[en] There is no information about the frequency of malignancy specifically in the case of thyroid nodules with highly suspicious sonographic features, but with two fine needle aspiration (FNA) showing benign cytology. This was the objective of the study. Subjects and methods: We report the results of 105 patients with thyroid nodules considered 'highly suspicious' according to the ultrasonographic classification of American Thyroid Association, in whom FNA revealed benign cytology on two occasions (interval of 6 months). Results: Thyroidectomy was performed in 11 cases due to desire of the patient or significant growth of the nodule. In these patients, cytology continued to be benign in 9, was non-diagnostic in 1, and suspicious in 1. Histology revealed papillary carcinoma in only one nodule. In patients in whom a third FNA was obtained for this study (n = 94), cytology continued to be benign in 86, became non-diagnostic in 5, indeterminate in 2, and suspicious in 1. The last 8 patients (with non-benign cytology) were submitted to thyroidectomy and histology revealed malignancy in only one nodule. Conclusion: The rate of malignancy found here for nodules with highly suspicious sonographic features, even after two FNA showing benign cytology, was 2%. We believe that in these cases, the continuation of follow-up consisting of ultrasound at intervals of 2 years may still be adequate. (author)