String Matching and 1d Lattice Gases

We calculate the probability distributions for the number of occurrences $n$ of a given $l$ letter word in a random string of $k$ letters. Analytical expressions for the distribution are known for the asymptotic regimes (i) $k \gg r^l \gg 1$ (Gaussian) and $k,l \to \infty$ such that $k/r^l$ is finite (Compound Poisson). However, it is known that these distributions do now work well in the intermediate regime $k \gtrsim r^l \gtrsim 1$. We show that the problem of calculating the string matching probability can be cast into a determining the configurational partition function of a 1d lattice gas with interacting particles so that the matching probability becomes the grand-partition sum of the lattice gas, with the number of particles corresponding to the number of matches. We perform a virial expansion of the effective equation of state and obtain the probability distribution. Our result reproduces the behavior of the distribution in all regimes. We are also able to show analytically how the limiting distributions arise. Our analysis builds on the fact that the effective interactions between the particles consist of a relatively strong core of size $l$, the word length, followed by a weak, exponentially decaying tail. We find that the asymptotic regimes correspond to the case where the tail of the interactions can be neglected, while in the intermediate regime they need to be kept in the analysis. Our results are readily generalized to the case where the random strings are generated by more complicated stochastic processes such as a non-uniform letter probability distribution or Markov chains. We show that in these cases the tails of the effective interactions can be made even more dominant rendering thus the asymptotic approximations less accurate in such a regime.Comment: 44 pages and 8 figures. Major revision of previous version. The lattice gas analogy has been worked out in full, including virial expansion and equation of state. This constitutes the main part of the paper now. Connections with existing work is made and references should be up to date now. To be submitted for publicatio

An overview of historical and contemporary concrete shells, their construction and factors in their general disappearance

Only through understanding why concrete shells’ loss in popularity over the course of modern history can designers be equipped with the skills to create and apply this type of construction. Through modifications to design processes, construction stages, material understanding and relevant formwork improvements will architects and designers be able to meet the demands of the 21st century and beyond. To understand why concrete shells are no longer commonly built is to understand its construction process. An amorphous material, the fundamental relationship between formwork and the resultant concrete shell needs to be raised, appreciated, understood and analyzed for a holistic understanding of concrete shells. Through understanding this, issues and factors affecting concrete shells can be tackled and designed out in reviving this type of structures because they can be efficient in structural performance, economical in cost and provide high aesthetic value. This paper discusses concrete shells as an architectural solution by asking the question to what constituted their popularity and factors that led to their demise in the modern age of technological advancement, construction process and environmental concerns. This paper presents a cultural perspective and an overview of seminal, historical and contemporary concrete shells so as to bring about a renaissance of such structures in our built environment once again because of all the benefits it can offer.</p

Prevalence and risk factors of allergies in turkey (PARFAIT): Results of a multicentre cross-sectional study in adults

The Prevalence and Risk Factors of Allergies in Turkey (PARFAIT) study was planned to evaluate the prevalence of and risk factors for asthma and allergic diseases in Turkey. The present analysis used data from 25,843 parents of primary school children, obtained from a cross-sectional questionnaire-based study. A total of 25,843 questionnaires from 14 centres were evaluated. In rural areas, the prevalences asthma, wheezing, allergic rhinitis and eczema in males were: 8.5% (95% confidence interval (CI) 7.9-9.1%), 13.5% (95% CI 12.8-14.2%), 17.5% (95% CI 16.7-18.2%) and 10.8% (95% CI 10.211.4%), respectively; and in females were: 11.2% (95% CI 10.9-11.8%), 14.7% (95% CI 14.315.1%), 21.2% (95% CI 20.4-22.0%) and 13.1% (95% CI 2.4-13.8%), respectively. In urban areas, the corresponding prevalences in males were: 6.2% (95% CI 5.8-6.6%), 10.8% (95% CI 10.311.3%), 11.7% (95% CI 11.4-12.0%) and 6.6% (95% CI 6.2-7.0%), respectively; and in females were: 7.5 % (95% CI 7.9-7.1%), 12.0% (95% CI 11.7-12.3%), 17.0% (95% CI 16.4-17.6%) and 7.3% (95% CI 6.9-7.7%), respectively. Having an atopic first-degree relative or any other atopic diseases had significant effects on the prevalence of allergic diseases. Housing conditions, such as living in a shanty-type house, visible moulds at home and use of wood or biomass as heating or cooking material were associated with one or more allergic diseases. Although genetic susceptibility is strongly associated, country-and population-based environmental factors may contribute to increased prevalence rates of allergic diseases. Copyright © ERS Journals Ltd 2009

Wikipedia Information Flow Analysis Reveals the Scale-Free Architecture of the Semantic Space

In this paper we extract the topology of the semantic space in its encyclopedic acception, measuring the semantic flow between the different entries of the largest modern encyclopedia, Wikipedia, and thus creating a directed complex network of semantic flows. Notably at the percolation threshold the semantic space is characterised by scale-free behaviour at different levels of complexity and this relates the semantic space to a wide range of biological, social and linguistics phenomena. In particular we find that the cluster size distribution, representing the size of different semantic areas, is scale-free. Moreover the topology of the resulting semantic space is scale-free in the connectivity distribution and displays small-world properties. However its statistical properties do not allow a classical interpretation via a generative model based on a simple multiplicative process. After giving a detailed description and interpretation of the topological properties of the semantic space, we introduce a stochastic model of content-based network, based on a copy and mutation algorithm and on the Heaps' law, that is able to capture the main statistical properties of the analysed semantic space, including the Zipf's law for the word frequency distribution

A sequence variant at 4p16.3 confers susceptibility to urinary bladder cancer

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldPreviously, we reported germline DNA variants associated with risk of urinary bladder cancer (UBC) in Dutch and Icelandic subjects. Here we expanded the Icelandic sample set and tested the top 20 markers from the combined analysis in several European case-control sample sets, with a total of 4,739 cases and 45,549 controls. The T allele of rs798766 on 4p16.3 was found to associate with UBC (odds ratio = 1.24, P = 9.9 x 10(-12)). rs798766 is located in an intron of TACC3, 70 kb from FGFR3, which often harbors activating somatic mutations in low-grade, noninvasive UBC. Notably, rs798766[T] shows stronger association with low-grade and low-stage UBC than with more aggressive forms of the disease and is associated with higher risk of recurrence in low-grade stage Ta tumors. The frequency of rs798766[T] is higher in Ta tumors that carry an activating mutation in FGFR3 than in Ta tumors with wild-type FGFR3. Our results show a link between germline variants, somatic mutations of FGFR3 and risk of UBC.info:eu-repo/grantAgreement/EC/FP7/21807

Management of non-muscle-invasive and muscle-invasive bladder cancers

Bladder cancer (BC) is the 7th most commonly diagnosed cancer in men worldwide, while it declines to 11th when both sexes are considered. The worldwide age-standardized incidence rate (per 100,000 person/years) is 9.0 for men and 2.2 for women. Europe has among the highest incidence rates of BC in the world, where the age-standardized incidence rate is 19.1 for men and 4.0 for women. The overall burden was greater in men; however varying incidence trends by gender were reported recently in some countries, with rates drop in male and increase in female population. The management of BC should be tailored according to the disease stage, grade, and patient-related factors at the presentation. In this chapter, we will discuss the management of non-muscle- invasive disease and the surgical management of muscle-invasive disease. © Springer International Publishing AG 2017