Temporal variation in the coral reefs of the east coast of the inner gulf of Thailand

A series of permanent line transects established on fourteen reefs on the eastern seaboard of the Gulf of Thailand were monitored through a three-year period (1995- 1998) using a video transect method. Hierarchical cluster analysis shows three distinctive reef community types dominated by 1) Porites, 2) Acropora and 3) zoantharians. The reefs are developed under naturally turbid conditions and relatively low salinity due to the proximity of four major river outlets located in the uppermost area of the gulf. The number of Acroporid species on the reefs is positively correlated with distance from the major flver outlets. Eighty-seven species of scleractinian coral were found on the transects. Over the three-year period, the comparison of 1995-97-98 matched stations using Repeated Measures ANOV A reveals no significant time-dependent change in percent area cover of reef components except for an overall significant reduction in the faviid coral component. In the 1997-98 matched station comparison, statistical tests reveal significant increases in both Acropora and Porites components that translated into an overall increase in total living coral cover. These findings indicate that the overall environmental conditions have been favorable for coral growth. Outcompetition of massive corals by faster growing corals on several reefs also indicates conditions favorable for reef expansion. Growth of newlyformed Porites colonies over primary rock substrate and dead coral skeleton was presumably responsible for its rapid increase. Although these reefs are in an area of rapid industrialization and population growth, resultant anthropogenic effects have not yet stopped active coral accretion.

Flow injection analysis (FIA) determination of lead by hydride generation in banded coral skeletons /

A flow injection hydride generation direct current plasma atomic emission spectrometric (FI-HG-DCP-AES) method was developed for the determination of lead at ng.ml-l level. Potassium ferricyanide (K3Fe(CN)6) was used along with sodium tetrahydroborate(III) (NaBH4) to produce plumbane (PbH4) in an acid medium. The design of a gas-liquid separator (hydride generator) was tested and the parameters of the flow injection system were optimized to achieve a good detection limit and sample throughput. The technique developed gave a detection limit of 0.7 ng.ml-l(3ob). The precision at 20 ng.ml"* level was 1.6 % RSD with 1 1 measurements (n=l 1). Volume of sample loop was 500 |J.l. A sample throughput of 120 h"^ was achieved. The transition elements, Fe(II), FeOH), Cd(n), Co(II), Mn(n), Ni(II) and Zn(n) do not interfere in this method but 1 mg,l'l Cu(II) will suppress 50 % of the signal from a sample containing 20 ng.ml'l Pb. This method was successfully applied to determine lead in a calcium carbonate (CaC03) matrix of banded coral skeletons from Si-Chang Island in Thailand.

The effects of language complexity in a counterattitudinal appeal to laypeople : an application of the elaboration likelihood model of persuasion to a legal issue

The effects of a complexly worded counterattitudinal appeal on laypeople's attitudes toward a legal issue were examined, using the Elaboration Likelihood Model (ELM) of persuasion as a theoretical framework. This model states that persuasion can result from the elaboration and scrutiny of the message arguments (i.e., central route processing), or can result from less cognitively effortful strategies, such as relying on source characteristics as a cue to message validity (i.e., peripheral route processing). One hundred and sixty-seven undergraduates (85 men and 81 women) listened to eitller a low status or high status source deliver a counterattitudinal speech on a legal issue. The speech was designed to contain strong or weak arguments. These arguments were 'worded in a simple and, therefore, easy to comprehend manner, or in a complex and, therefore, difficult to comprehend manner. Thus, there were three experimental manipulations: argument comprehensibility (easy to comprehend vs. difficult to comprehend), argumel11 strength (weak vs. strong), and source status (low vs. high). After listening to tIle speec.J] participants completed a measure 'of their attitude toward the legal issue, a thought listil1g task, an argument recall task,manipulation checks, measures of motivation to process the message, and measures of mood. As a result of the failure of the argument strength manipulation, only the effects of the comprehel1sibility and source status manipulations were tested. There was, however, some evidence of more central route processing in the easy comprehension condition than in the difficult comprehension condition, as predicted. Significant correlations were found between attitude and favourable and unfavourable thoughts about the legal issue with easy to comprehend arguments; whereas, there was a correlation only between attitude and favourable thoughts 11 toward the issue with difficult to comprehend arguments, suggesting, perhaps, that central route processing, \vhich involves argument scrutiny and elaboration, occurred under conditions of easy comprehension to a greater extent than under conditions of difficult comprehension. The results also revealed, among other findings, several significant effects of gender. Men had more favourable attitudes toward the legal issue than did women, men recalled more arguments from the speech than did women, men were less frustrated while listening to the speech than were ,vomen, and men put more effort into thinking about the message arguments than did women. When the arguments were difficult to comprehend, men had more favourable thoughts and fewer unfavourable thoughts about the legal issue than did women. Men and women may have had different affective responses to the issue of plea bargaining (with women responding more negatively than men), especially in light of a local and controversial plea bargain that occurred around the time of this study. Such pre-existing gender differences may have led to tIle lower frustration, the greater effort, the greater recall, and more positive attitudes for men than for WOlnen. Results· from this study suggest that current cognitive models of persuasion may not be very applicable to controversial issues which elicit strong emotional responses. Finally, these data indicate that affective responses, the controversial and emotional nature ofthe issue, gender and other individual differences are important considerations when experts are attempting to persuade laypeople toward a counterattitudinal position.

Enabling and Measuring Complexity in Evolving Designs using Generative Representations for Artificial Architecture

As the complexity of evolutionary design problems grow, so too must the quality of solutions scale to that complexity. In this research, we develop a genetic programming system with individuals encoded as tree-based generative representations to address scalability. This system is capable of multi-objective evaluation using a ranked sum scoring strategy. We examine Hornby's features and measures of modularity, reuse and hierarchy in evolutionary design problems. Experiments are carried out, using the system to generate three-dimensional forms, and analyses of feature characteristics such as modularity, reuse and hierarchy were performed. This work expands on that of Hornby's, by examining a new and more difficult problem domain. The results from these experiments show that individuals encoded with those three features performed best overall. It is also seen, that the measures of complexity conform to the results of Hornby. Moving forward with only this best performing encoding, the system was applied to the generation of three-dimensional external building architecture. One objective considered was passive solar performance, in which the system was challenged with generating forms that optimize exposure to the Sun. The results from these and other experiments satisfied the requirements. The system was shown to scale well to the architectural problems studied.