Variant alleles of the CYP1B1 gene are associated with colorectal cancer susceptibility

<p>Abstract</p> <p>Background</p> <p>CYP1B1 is a P450 enzyme which is involved in the activation of pro-carcinogens to carcinogens as well as sex hormone metabolism. Because differences in the activity of the enzyme have been correlated with variant alleles of single nucleotide polymorphisms (SNPs), it represents an attractive candidate gene for studies into colorectal cancer susceptibility.</p> <p>Methods</p> <p>We genotyped 597 cancer patients and 597controls for three CYP1B1 SNPs, which have previously been shown to be associated with altered enzymatic activity. Using the three SNPs, eight different haplotypes were constructed. The haplotype frequencies were estimated in cases and controls and then compared. The odds ratio for each tumour type, associated with each haplotype was estimated, with reference to the most common haplotype observed in the controls.</p> <p>Results</p> <p>The three SNPs rs10012, rs1056827 and rs1056836 alone did not provide any significant evidence of association with colorectal cancer risk. Haplotypes of rs1056827 and rs10012 or rs1056827 and rs1056836 revealed an association with colorectal cancer which was significantly stronger in the homozygous carriers. One haplotype was under represented in the colorectal cancer patient group compared to the control population suggesting a protective effect.</p> <p>Conclusion</p> <p>Genetic variants within the CYP1B1 that are associated with altered function appear to influence susceptibility to a colorectal cancer in Poland. Three haplotypes were associated with altered cancer risk; one conferred protection and two were associated with an increased risk of disease. These observations should be confirmed in other populations.</p

Model confidence sets and forecast combination: an application to age-specific mortality

Background: Model averaging combines forecasts obtained from a range of models, and it often produces more accurate forecasts than a forecast from a single model. Objective: The crucial part of forecast accuracy improvement in using the model averaging lies in the determination of optimal weights from a finite sample. If the weights are selected sub-optimally, this can affect the accuracy of the model-averaged forecasts. Instead of choosing the optimal weights, we consider trimming a set of models before equally averaging forecasts from the selected superior models. Motivated by Hansen et al. (2011), we apply and evaluate the model confidence set procedure when combining mortality forecasts. Data & Methods: The proposed model averaging procedure is motivated by Samuels and Sekkel (2017) based on the concept of model confidence sets as proposed by Hansen et al. (2011) that incorporates the statistical significance of the forecasting performance. As the model confidence level increases, the set of superior models generally decreases. The proposed model averaging procedure is demonstrated via national and sub-national Japanese mortality for retirement ages between 60 and 100+. Results: Illustrated by national and sub-national Japanese mortality for ages between 60 and 100+, the proposed model-average procedure gives the smallest interval forecast errors, especially for males. Conclusion: We find that robust out-of-sample point and interval forecasts may be obtained from the trimming method. By robust, we mean robustness against model misspecification

Assessing time series models for forecasting international migration : lessons from the United Kingdom

Funding: This work was funded by the Migration Advisory Committee (MAC), UK Home Office, under the Home Office Science contract HOS/14/040, and also supported by the ESRC Centre for Population Change grant ES/K007394/1.Migration is one of the most unpredictable demographic processes. The aim of this article is to provide a blueprint for assessing various possible forecasting approaches in order to help safeguard producers and users of official migration statistics against misguided forecasts. To achieve that, we first evaluate the various existing approaches to modelling and forecasting of international migration flows. Subsequently, we present an empirical comparison of ex post performance of various forecasting methods, applied to international migration to and from the United Kingdom. The overarching goal is to assess the uncertainty of forecasts produced by using different forecasting methods, both in terms of their errors (biases) and calibration of uncertainty. The empirical assessment, comparing the results of various forecasting models against past migration estimates, confirms the intuition about weak predictability of migration, but also highlights varying levels of forecast errors for different migration streams. There is no single forecasting approach that would be well suited for different flows. We therefore recommend adopting a tailored approach to forecasts, and applying a risk management framework to their results, taking into account the levels of uncertainty of the individual flows, as well as the differences in their potential societal impact.Publisher PDFPeer reviewe

Typical tasks performed by combustion engine during operation and their modeling in the dynamometer laboratory testing

W artykule została zaprezentowana metoda syntezy testów jezdnych na podstawie analizy typowych zadań realizowanych przez silnik spalinowy. Algorytm obliczeniowy składa się z analizy pracy silnika służącej wyodrębnieniu typowych zadań i ich usystematyzowaniu oraz z syntezy nowych testów o charakterze uproszczonym. Celem tak powstałych testów jezdnych jest odwzorowywanie możliwie najbardziej dokładnie tych procesów pracy silnika, które są najbardziej interesujące z punktu widzenia ekologicznego lub które występują najczęściej w trakcie rzeczywistej eksploatacji silnika.This paper presents the method of synthesis driving tests based on analysis typical tasks performed by combustion engine. Calculation algorithm consist of analysis of engine work to extract the typical tasks and systematization of them, and after that synthesis of new tests with simplified character. The aim of the resulting driving tests is modeling in the most accurate way these processes of engine work that are the most interesting from the ecological point of view or are the most common in the real engine exploitation

Detection of driver intention algoritm near the pedestrian crossing

Praca dotyczy projektu urządzenia montowanego do samochodów, służącego do sygnalizacji pieszym czekającym na przejściach, czy kierowa rozpoczął zatrzymywanie pojazdu w celu ustąpienia pierwszeństwa. Jednym z kluczowych elementów takiego projektu jest przygotowanie algorytmu śledzącego warunki ruchu samochodu i wysyłającego do sygnalizatora informacje o przewidywanych intencjach kierowcy. Niniejsza praca koncentruje się na analizie technicznych możliwości opracowania takiego algorytmu. W tym celu zostały przeprowadzone wstępne badania drogowe, wykonano ich analizę i na tej podstawie przygotowano wstępny algorytm decyzyjny. W dalszej kolejności przeprowadzono matematyczną symulację jego działania. Pokazano, że w samych przebiegach prędkości jazdy kryją się przesłanki pozwalające przewidzieć dalsze zachowanie kierowcy. Na tej podstawie oceniono, że kolejne prace tego typu są zasadne i mogą doprowadzić do opracowania niezawodnego sygnalizatora intencji kierowcy.The work relates to the project of equipment that will be mounted on cars to signaling for pedestrians waiting on the crossings if the driver is going to stop the vehicle to give the way. One of the key elements of this project is to develop an algorithm following the car moving conditions and sending to the indicator information about estimated driver intentions. This work focused on the analysis of the technical possibilities of the development of such algorithm. For this purpose, preliminary road tests were conducted, them analysis was done and on this basis the preliminary decision algorithm was prepared. Next, the mathematical simulation of its work was conducted. It is shown that the speed runs hide premise that allow to estimate next driver behavior. On this basis it was appraise that successive works are reasonable and they may lead to development the reliable indicator of driver intentions

Selection of the vehicle speed waveforms filtering method

Przebieg prędkości pojazdu stanowi przykład funkcji stosunkowo trudnej do filtrowania. Metoda filtrująca musi bowiem cechować się nie tylko określonymi właściwościami widma częstotliwościowego. Musi także wykazywać inne właściwości, które zostaną bliżej omówione w niniejszym artykule. W przypadku złego doboru algorytmu filtracji często okazuje się, że przetworzony przebieg zawiera zniekształcenia sygnału, które uniemożliwiają jego poprawną interpretację fizyczną. W artykule porównano ze sobą 2 popularne metody filtracji wraz z ich podstawowymi modyfikacjami, omówiono ich wady i zalety, a także przedstawiono ich praktyczne zastosowanie dla zarejestrowanych przebiegów prędkości pojazdu. Oceniono również, które rozwiązanie może być częściej przydatne podczas opracowywania wyników badań stanowiących przebieg prędkości pojazdu.The vehicle speed waveforms is an example of the function that is relatively difficult to filter. In this case the filtering method must be characterized not only by specific properties of the frequency spectrum. It must also meet other conditions that will be discussed in more detail in this article. In the case of wrong selection of filtering algorithm it often turns out that the processed waveform contains signal distortions witch make it impossible to correct physical interpretation of given signal. The article compares two popular filtering methods with their basic modifications, discusses their advantages and disadvantages and shows their practical application for registered waveforms vehicle speed. It aIso evaluates which solution can be more useful during the development of research results that covering the course of vehicle speed