The developement [sic] of phosphorometric, fluorometric and absorption analyses for the measurement of carbamates and carbamic acids as an explanation of carbon dioxide transport in blood

Phosphorometric, flourometric, and absorption analyses have been developed for the measurement of amino acids, carbamic acids, and carbamates. The absorption analysis may be done in any solvent while the other two methods are limited to non-re-emitting solvents. Water is not excluded in any of the analyses. A carbamate or carbamic acid can be detected even in the presence of amino acids as low as 0.5%, with an overall accuracy of ± 0.3)%. Tentative assignments have been made for the n, π* direct triplet excitation bands for the carbonyls of glycine and its carbamic acid, acetyl chloride, ethyl acetate, and acetamide. The first two are based on absorption and phosphorescence data while the last four are based on phosphorescence data alone

Defining, describing, and assessing growth determinacy as a mechanism of plant species codominance

2022 Spring.Includes bibliographical references.To view the abstract, please see the full text of the document

Modeling Member Responses to the Farmer Owned Cooperative's Alternative Capital Management Strategies

Agricultural Finance, Agribusiness,

Reducing alcohol and other drug related harm

High levels of alcohol and other drug use-related harm among Indigenous Australians are both a consequence of, and contribute to, the health and social gap between them and non-Indigenous Australians. This resource sheet summarises current evidence on the issue. Reduction of harmful alcohol and other drug (AOD) use must include broad strategies to address the underlying social factors which predispose towards, or protect against, harmful use; and strategies specifically targeting harmful use itself. AOD-specific strategies should aim to prevent or minimise the uptake of harmful use; provide safe care for those who are intoxicated; provide treatment for those who are dependent; support those whose harmful AOD use has left them disabled or cognitively impaired; and support those whose lives are affected by others’ harmful AOD us

Qualitatively different approaches to simple arithmetic

This study explores the qualitative difference in performance between those who are more successful and those who are less successful in simple arithmetic. In the event that children are unable to retrieve a basic number combination the study identifies that there is a spectrum of performance between children who mainly use procedures, such as count-all in addition and take-away in subtraction, to those who handle simple arithmetic in a much more flexible way. Two independent studies are described The first contrasts the performances of children in simple arithmetic. It considers teacher selected pupils of different ability from within each year group from 7+ to 12+. It takes a series of snapshots of different groups of children and considers their responses to a series of simple number combinations. This first experiment shows qualitatively different thinking in which the less successful children are seen to focus more on the use of procedures and in the development of competence in utilising them. The more successful appear to have developed a flexible mode of thinking which is not only capable of stimulating their selection of more efficient procedures but, the procedures they select are then used in an efficient and competent way. However, the use of procedures amongst the more successful is seen to be only one of two alternative approaches that they use. The other approach involves the flexible use of mathematical objects, numbers, that are derived from encapsulated processes. The below-average children demonstrate little evidence of the flexible use of encapsulated processes. It is the ability of the more able children to demonstrate flexibility through the use of efficient procedures and/or the use of encapsulated processes that stimulates the development of the theory of procepts. This theory utilises the duality which is ambiguously inherent in arithmetical symbolism to establish a framework from which we may identify the notion of proceptual thinking. The second study considers the development of a group of children over a period of nearly a year. This study relates to aspects of the numerical component of the standardised tests in mathematics which form part of the National Curriculum. It provides the data which gives support to the theory and provides evidence to confirm the snap shots taken of children at the age of 7+ and 8+. It indicates that children who possess procedural competence may achieve the same level of attainment as those who display proceptual flexibility at one level of difficulty but they may not possess the appropriate mental tools to cope with the next. The evidence of the study supports the hypothesis that there is a qualitative difference in children's arithmetical thinking

XLVII. Zoological notices

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LXVIII. A monograph of the genus Teredo of Linné, with descriptive characters of the species in the British Museum

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What is the object of the encapsulation of a process?

Several theories have been proposed to describe the transition from process to object in mathematical thinking. Yet, what is the nature of this ''object'' produced by the ''encapsulation'' of a process? Here, we outline the development of some of the theories (including Piaget, Dienes, Davis, Greeno, Dubinsky, Sfard, Gray, and Tall) and consider the nature of the mental objects (apparently) produced through encapsulation and their role in the wider development of mathematical thinking. Does the same developmental route occur in geometry as in arithmetic and algebra? Is the same development used in axiomatic mathematics? What is the role played by imagery