Continuous Determination of Carbon Monoxide and Hydrocarbons in Air by a Modified Infrared Analyzer

The original goals of this project¹ were to establish the shape of a smoke curve for fine suspended particulates in New York City comparable to the International Smoke Curve used in British and other European practice, and to relate two commonly used reporting units of surface concentration, μg/m³ (European practice) and Coh/1000 lineal feet (United States practice), to each other. While not directly a goal of the project, it was essential in the course of work to study the relationship between particulate density readings taken for one hour and two hour sampling periods. Progress toward achievement of these goals is presented in the following pages.     

The efficacy of maternal age screening for Down's syndrome in Wessex

The uptake of amniocentesis in Wessex for the period 1986–1988 was 36 per cent (2873 of 8004 births), a proportion that has not altered significantly since 1984. There is a large difference in uptake between women in the lower risk age group, 35–36 years, and those in the higher risk group, 37 + years, and very considerable differences in uptake among different districts. The prenatal detection over the 3-year study period for women aged 35 or more, after correction for spontaneous loss of Down's syndrome fetuses between prenatal detection and birth, is 53 per cent, a figure that must be inflated due to our failure to ascertain all liveborn Down's syndrome patients.     

Phylogeography of the diamond turbot (Hypsopsetta guttulata) across the Baja California Peninsula

We compared morphology and sequenced nuclear and mitochondrial genes from 11 populations of a previously genetically unstudied “Baja California disjunct” species, the diamond turbot (Hypsopsetta guttulata). This species exhibits very limited adult movement and restriction to soft-bottom habitats but has a moderately long pelagic larval duration. Therefore, if pelagic larval duration is correlated with gene flow between Gulf of California and Pacific populations, we expect a reduced level of genetic and morphological differentiation. However, if adult habitat and ecology have more effect on gene flow, we expect the populations in the two bodies of water to be more highly differentiated. We used logistic regression to compare morphological features and phylogenetic and population genetic analyses to compare nucleotide sequence data. Gulf of California H. guttulata are different from Pacific populations in morphology and both mitochondrial and nuclear gene sequences. MtDNA shows reciprocal monophyly, and nuclear sequences from the Gulf of California formed a monophyletic group. Population genetic analyses also suggest further population subdivision within the Pacific and within the Gulf of California. We argue that adult ecology has a significant effect on migration rates among populations in the Pacific Ocean and the Gulf of California.     

Predicting leadership using nutrient requirements and dominance rank of group members

Group members must decide collectively when and where to go despite their different nutrient requirements. One mechanism underlying consensus decisions is the proposition by one individual to move. The individual frequently initiating movements is often named a “leader”, and this individual may be the most dominant, the oldest or may have the greatest physiological needs. However, high-ranking individuals are often those with the highest body mass, and thus the highest nutrient requirements. In this study, we use a state-dependent model to assess the importance of dominance and nutrient requirements to the initiation of group movements, testing different combinations of effects of these interacting factors. We first show using a theoretical approach that whatever the correlation between the dominance hierarchy and body mass, all decision-making systems are viable (or stable). However, in most cases, one individual does become the leader, and nutrient requirements appear to be more important for determining which individual will emerge as the leader than pre-existing individual characteristics such as their dominance rank. We obtained the same result when we compared the simulated distributions of initiations to the observed distributions in three macaque species. Results of our comparison of three macaque groups suggest that we can predict which group member will be the leader simply by knowing its body mass and its reproductive state. Understanding the link between dominance, needs and leadership may be a key to understanding consensus decisions and collective motion in animal groups, and might provide insight into the management of animal groups and their conservation.     

Living with living systems: The co-evolution of values and valuation

This article explores features of the environmental valuation process through a co-evolutionary approach. Based on established works concerning complexity, living systems, and social, economic, evolutionary and hierarchy theories, it is argued that a special form of recursive co-evolution takes place between articulated values and methods of value articulation, within the environmental valuation system. It is proposed that this co-evolutionary approach provides new insights into (1) the process of environmental preference formation and (2) the phenomenon of value incommensurability. Finally, it is suggested that this approach also reveals that monetary unit-based environmental valuation methods are counter-productive to their own purpose of 'taking the economic worth of un-priced environmental goods and service into account.' This constitutes a new critique of monetary valuation, which is not addressed by a pragmatic defence of the practice. It is suggested that, in lieu of monetary valuation, taking the economic worth of these phenomena into account may be better served by focusing efforts on the design of new value articulation methods that are capable of expressing their priceless economic worth.