Sound Basis (sound + basis)

Distribution by Scientific Domains


Selected Abstracts


Genome-scale models of bacterial metabolism: reconstruction and applications

FEMS MICROBIOLOGY REVIEWS, Issue 1 2009
Maxime Durot
Abstract Genome-scale metabolic models bridge the gap between genome-derived biochemical information and metabolic phenotypes in a principled manner, providing a solid interpretative framework for experimental data related to metabolic states, and enabling simple in silico experiments with whole-cell metabolism. Models have been reconstructed for almost 20 bacterial species, so far mainly through expert curation efforts integrating information from the literature with genome annotation. A wide variety of computational methods exploiting metabolic models have been developed and applied to bacteria, yielding valuable insights into bacterial metabolism and evolution, and providing a sound basis for computer-assisted design in metabolic engineering. Recent advances in computational systems biology and high-throughput experimental technologies pave the way for the systematic reconstruction of metabolic models from genomes of new species, and a corresponding expansion of the scope of their applications. In this review, we provide an introduction to the key ideas of metabolic modeling, survey the methods, and resources that enable model reconstruction and refinement, and chart applications to the investigation of global properties of metabolic systems, the interpretation of experimental results, and the re-engineering of their biochemical capabilities. [source]


Top-down control of phytoplankton: the role of time scale, lake depth and trophic state

FRESHWATER BIOLOGY, Issue 12 2002
JÜrgen Benndorf
SUMMARY 1.,One of the most controversial issues in biomanipulation research relates to the conditions required for top-down control to cascade down from piscivorous fish to phytoplankton. Numerous experiments have demonstrated that Phytoplankton biomass Top-Down Control (PTDC) occurs under the following conditions: (i) in short-term experiments, (ii) shallow lakes with macrophytes, and (iii) deep lakes of slightly eutrophic or mesotrophic state. Other experiments indicate that PTDC is unlikely in (iv) eutrophic or hypertrophic deep lakes unless severe light limitation occurs, and (v) all lakes characterised by extreme nutrient limitation (oligo to ultraoligotrophic lakes). 2.,Key factors responsible for PTDC under conditions (i) to (iii) are time scales preventing the development of slow-growing inedible phytoplankton (i), shallow depth allowing macrophytes to become dominant primary producers (ii), and biomanipulation-induced reduction of phosphorus (P) availability for phytoplankton (iii). 3.,Under conditions (iv) and (v), biomanipulation-induced reduction of P-availability might also occur but is insufficient to alter the epilimnetic P-content enough to initiate effective bottom-up control (P-limitation) of phytoplankton. In these cases, P-loading is much too high (iv) or P-content in the lake much too low (v) to initiate or enhance P-limitation of phytoplankton by a biomanipulation-induced reduction of P-availability. However, PTDC may exceptionally result under condition (iv) if high mixing depth and/or light attenuation cause severe light limitation of phytoplankton. 4.,Recognition of the five different conditions reconciles previous seemingly contradictory results from biomanipulation experiments and provides a sound basis for successful application of biomanipulation as a tool for water management. [source]


Exploratory study in tourism: designing an initial, qualitative phase of sequenced, mixed methods research

INTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 5 2010
Peter Mason
Abstract Exploratory studies in the social sciences are being increasingly advocated, particularly in relation to new research themes or when addressing an existing issue from a new perspective. Although exploration is usually the starting point, it is frequently part of a sequence of research stages. However, until recently the actual process of conducting such exploratory research within the leisure and tourism field has received little attention. This is due not just to perceptions that exploration is merely the initial step in a longer research process, but significantly, because there is a lack of guidance on how to conduct such research. This paper argues that when the overall tourism research study involves the use of mixed methods, an initial exploratory stage conducted as part of a sequential research process, requires a systematic approach to achieve a reliable platform for further investigation. The paper shows how and why a systematic research design process in the exploratory stage can enhance the value of studies, when the initial qualitative stage is to be followed by a quantitative phase. Three phases of an exploratory qualitative research design process are identified: preparation, development and refinement. Criteria for assessing the suitability of qualitative data collection techniques are proposed. It is argued that careful attention to the process of designing the initial exploratory qualitative stage constitutes the necessary condition for achieving results that will form a sound basis for the next quantitative sequence of research. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Dependent and Accountable: Evidence from the Modern Theory of Central Banking

JOURNAL OF ECONOMIC SURVEYS, Issue 5 2000
Gustavo Piga
In this paper we take another look at the literature on central bank independence. We show that the representative-agent approach to monetary policy is seriously flawed and does not provide a sound basis for deriving institutional solutions to the inflationary-bias. We then argue that the political approach to monetary policy provides a better account of the inflationary-bias and that this has important implications for the set-up of institutional arrangements, like central-bank independence, and the role of contractual arrangements, like indexation. Central bank independence, if appropriately modeled, can fail to reduce inflationary pressures in plausible circumstances. We then identify some issues in the theory of central banking that have not been clearly resolved and we offer some intuition as to the way they could be studied. We conclude by showing some potentially worrisome implications for the future of the European Monetary Union. [source]