University of Kiel

About: University of Kiel is a education organization based out in Kiel, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 27816 authors who have published 57114 publications receiving 2061802 citations. The organization is also known as: Christian Albrechts University & Christian-Albrechts-Universität zu Kiel.

Data Refinement: Model-Oriented Proof Methods and their Comparison

Abstract: The goal of this book is to provide a comprehensive and systematic introduction to the important and highly applicable method of data refinement and the simulation methods used for proving its correctness. The authors concentrate in the first part on the general principles needed to prove data refinement correct. They begin with an explanation of the fundamental notions, showing that data refinement proofs reduce to proving simulation. The topics of Hoare Logic and the Refinement Calculus are introduced and a general theory of simulations is developed and related to them. Accessibility and comprehension are emphasized in order to guide newcomers to the area. The book's second part contains a detailed survey of important methods in this field, such as VDM, and the methods due to Abadi & Lamport, Hehner, Lynch and Reynolds, Back's refinement calculus and Z. All these methods are carefully analysed, and shown to be either imcomplete, with counterexamples to their application, or to be always applicable whenever data refinement holds. This is shown by proving, for the first time, that all these methods can be described and analyzed in terms of two simple notions: forward and backward simulation. The book is self-contained, going from advanced undergraduate level and taking the reader to the state of the art in methods for proving simulation.

Genome-wide association study identifies two susceptibility loci for nonsyndromic cleft lip with or without cleft palate

Abstract: We conducted a genome-wide association study for nonsyndromic cleft lip with or without cleft palate (NSCL/P) in 401 affected individuals and 1,323 controls, with replication in an independent sample of 793 NSCL/P triads. We report two new loci associated with NSCL/P at 17q22 (rs227731, combined P = 1.07 x 10(-8), relative risk in homozygotes = 1.84, 95% CI 1.34-2.53) and 10q25.3 (rs7078160, combined P = 1.92 x 10(-8), relative risk in homozygotes = 2.17, 95% CI 1.32-3.56).

On the Cosmic Origins of Carbon and Nitrogen

Abstract: We analyze the behavior of N/O and C/O abundance ratios as a function of metallicity as gauged by O/H in large, extant Galactic and extragalactic H II region abundance samples. We compile and compare published yields of C, N, and O for intermediate mass and massive stars and choose appropriate yield sets based on analytical chemical evolution models fitted to the abundance data. We then use these yields to compute numerical chemical evolution models that satisfactorily reproduce the observed abundance trends and thereby identify the most likely production sites for carbon and nitrogen. Our results suggest that carbon and nitrogen originate from separate production sites and are decoupled from one another. Massive stars (M > 8 M☉) dominate the production of carbon, while intermediate-mass stars between 4 and 8 M☉, with a characteristic lag time of roughly 250 Myr following their formation, dominate nitrogen production. Carbon production is positively sensitive to metallicity through mass-loss processes in massive stars and has a pseudo-secondary character. Nitrogen production in intermediate mass stars is primary at low metallicity, but when 12 + log(O/H) > 8.3, secondary nitrogen becomes prominent, and nitrogen increases at a faster rate than oxygen—indeed, the dependence is steeper than would be formally expected for a secondary element. The observed flat behavior of N/O versus O/H in metal-poor galaxies is explained by invoking low star formation rates that flatten the age-metallicity relation and allow N/O to rise to observed levels at low metallicities. The observed scatter and distribution of data points for N/O challenge the popular idea that observed intermittent polluting by oxygen is occurring from massive stars following star bursts. Rather, we find most points cluster at relatively low N/O values, indicating that scatter is caused by intermittent increases in nitrogen caused by local contamination by Wolf-Rayet stars or luminous blue variables. In addition, the effect of inflow of gas into galactic systems on secondary production of nitrogen from carbon may introduce some scatter into N/O ratios at high metallicities.

Chapter 1 General Introduction: Clays, Clay Minerals, and Clay Science

Abstract: Publisher Summary This chapter attracts the attention of clay scientists in academe and industry as well as in politics (as research needs funding), and focuses on the importance of clay science to society and the quality of life The economic benefits seem evident because clays are abundant, widespread, and inexpensive compared with other raw materials The chapter discusses the industrial and environmental importance of clays and clay minerals The great variety of physical, chemical, and thermal treatments that may be used to modify clays and clay minerals provide unlimited scope for future applications, particularly in terms of protecting the environment Because of the multidisciplinary nature of clay science, its teaching is another challenging task By learning about the mineralogical, physico-chemical, and industrial aspects of clay science, students would not only gain an appreciation of the “scientific method” and the physical environment but also find suitable employment and a fulfilling career