BACKGROUND The enumeration of chemical graphs (molecular graphs) satisfying given constraints is one of the fundamental problems in chemoinformatics and bioinformatics because it leads to a variety of useful applications including structure determination and development of novel chemical compounds. RESULTS We consider the problem of enumerating chemical graphs with monocyclic structure (a gra...

À ma famille passée, présente et future 5 Table of contents Abbreviations 6 Abstract 7 Publication list 8 Introduction 9 Stable isotopes 11 General considerations 11 Definitions 12 Mechanisms of isotope fractionation 13 1) Physical fractionations 13 2) Chemical fractionations 14 Isotopomers 16 Measurements of isotope and isotopomer abundance 17 1) IRMS 17 3) FTIR 19 2) NMR 19 Climate change 23 ...

This work studies the problem of optimally locating sensors for monitoring chemical processes, formally known as the sensor network design and upgrade problem. This problem is an integer programming problem and has been solved to global optimality only using tree search methods using depth-first strategy. In this article, we exploit certain cost properties of the different nodes in the tree to ...

Background: A decision tree has been developed for evaluating risks posed by combined exposures to multiple chemicals. The decision tree divides combined exposures of humans and ecological receptors into groups where one or more components are a concern by themselves, where risks from the combined exposures are of low concern, and where there is a concern for the effects from the combined expos...

The diversity of species is striking, but can be far exceeded by the chemical diversity of compounds collected, produced or used by them. Here, we relate the specificity of plant-consumer interactions to chemical diversity applying a comparative network analysis to both levels. Chemical diversity was explored for interactions between tropical stingless bees and plant resins, which bees collect ...

Wood anatomical traits are important correlates of life-history strategies among tree species, yet little is known about wood chemical traits. Additionally, size-dependent changes in wood chemical traits have been rarely examined, although these changes may represent an important aspect of tree ontogeny. Owing to selection for pathogen resistance and biomechanical stability, we predicted that s...