Continuous cultivation of photosynthetic microorganisms: approaches, applications and future trends

The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modelling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed.This research work was supported by the grant SFRH/BPD/98694/2013 (Bruno Fernandes) from Fundacao para a Ciencia e a Tecnologia (Portugal). The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. The authors also thank the Project "BioInd Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" Co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDE

Attitudes of extension agents towards expert systems as decision support tools in Thailand

It has been suggested 'expert systems' might have a significant role in the future through enabling many more people to access human experts. It is, therefore, important to understand how potential users interact with these computer systems. This study investigates the effect of extension agents' attitudes towards the features and use of an example expert system for rice disease diagnosis and management(POSOP). It also considers the effect of extension agents' personality traits and intelligence on their attitudes towards its use, and the agents' perception of control over using it. Answers to these questions lead to developing better systems and to increasing their adoption. Using structural equation modelling, two models - the extension agents' perceived usefulness of POSOP, and their attitude towards the use of POSOP, were developed (Models ATU and ATP). Two of POSOP's features (its value as a decision support tool, and its user interface), two personality traits (Openness (0) and Extraversion (E)), and the agents' intelligence, proved to be significant, and were evaluated. The agents' attitude towards POSOP's value had a substantial impact on their perceived usefulness and their attitude towards using it, and thus their intention to use POSOP. Their attitude towards POSOP's user interface also had an impact on their attitude towards its perceived usefulness, but had no impact on their attitude towards using it. However, the user interface did contribute to its value. In Model ATU, neither Openness (0) nor Extraversion (E) had an impact on the agents' perceived usefulness indicating POSOP was considered useful regardless of the agents' personality background. However, Extraversion (E) had a negative impact on their intention to use POSOP in Model ATP indicating that 'introverted' agents had a clear intention to use POSOP relative to the 'extroverted' agents. Extension agents' intelligence, in terms of their GPA, had neither an impact on their attitude, nor their subjective norm (expectation of 'others' beliefs), to the use of POSOP. It also had no association with any of the variables in both models. Both models explain and predict that it is likely that the agents will use POSOP. However, the availability of computers, particularly their capacity, are likely to impede its use. Although the agents believed using POSOP would not be difficult, they still believed training would be beneficial. To be a useful decision support tool, the expert system's value and user interface as well as its usefulness and ease of use, are all crucially important to the preliminary acceptance of a system. Most importantly, the users' problems and needs should be assessed and taken into account as a first priority in developing an expert system. Furthermore, the users should be involved in the system development. The results emphasise that the use of an expert system is not only determined by the system's value and its user interface, but also the agents' perceived usefulness, and their attitude towards using it. In addition, the agents' perception of control over using it is also a significant factor. The results suggested improvements to the system's value and its user interface would increase its potential use, and also providing suitable computers, coupled with training, would encourage its use

The internal validity of treaties under German and Thai law

Die Wirksamkeit völkerrechtlicher Verträge liegt sowohl auf völkerrechtlicher als auch auf innerstaatlicher Ebene. Wie sie auf innerstaatlicher Ebene wirksam sein können, handelt es sich um das innerstaatliche Recht in drei Bereichen: Vertragsabschluss, Umsetzung völkerrechtlicher Verträge ins innerstaatliche Recht und die Anwendung völkerrechtlicher Verträge im innerstaatlichen Recht. Völkerrechtliche Verträge müssen zunächst nach innerstaatlichem Recht rechtsmäßig abgeschlossen werden. Danach müssen sie ins innerstaatliche Recht umgesetzt werden, damit sie im innerstaatlichen Recht angewendet werden können. Da Völkerrecht keine Regelung oder Voraussetzung der Umsetzung völkerrechtlicher Verträge ins innerstaatliche Recht bestimmt, können Staaten die Umsetzung selbst festlegen. Zwar völkerrechtliche Verträge rechtsmäßig abgeschlossen werden und ins innerstaatliche Recht umgesetzt werden, aber es kann nicht garantieren, dass sie im innerstaatlichen Recht wirksam sein kann. Sie oder ihre erfüllende Gesetze müssen von den Rechtsanwendungsorganen, Verwaltungsbehörder oder Gericht innerstaatlich beachtet und effektiv angewendet werden. Die innerstaatliche Wirksamkeit völkerrechtlicher Verträge nach deutschem und thailändischem Recht wird in drei Bereichen untersucht: Wie völkerrechtliche Verträge im deutschen und thailändischen Recht rechtsmäßig abgeschlossen werden, wie sie ins deutsche und thailändische Recht umgesetzt werden können und wie sie im deutschen und thailändischen Recht ausgeführt und angewendet werden können.The validity of Treaties depends on international and internal law. The internal validity of treaties shall be concerned in three spheres: the conclusion of Treaties, the conversion of treaties into internal law and the application of treaties in internal law. Treaties must be first concluded completely under the internal law. Af-ter the complete conclusion the treaties must be converted in order to be applied in internal law. Since international law does not direct any rules or conditions to convert the treaties into the internal law. The conversion of treaties into the internal law can be specified by the states. Although treaties were concluded completely under the internal law and were converted into the internal law, it does not guarantee that the treaties shall be valid in the internal law. The treaties must be attended by the states authorities, administrative Organs and Judge, to apply and enforce effectively in the internal law. The internal validity of treaties under German and Thai law shall be examined in this three spheres: the conclusion of treaties under German and Thai law, the conversion of treaties into German and Thai law and the application and enforcement in German and Thai law