| 11. |
- Hjorth, Peder, et al.
(author)
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Navigating towards sustainable development: A system dynamics approach
- 2006
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In: Futures. - : Elsevier BV. - 0016-3287. ; 38:1, s. 74-92
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Journal article (peer-reviewed)abstract
- Traditional fragmented and mechanistic science is unable to cope with issues about sustainability, as these are often related to complex, self-organizing systems. In the paper, sustainable development is seen as an unending process defined neither by fixed goals nor by specific means of achieving them. It is argued that, in order to understand the sources of and the solutions to modern problems, linear and mechanistic thinking must give way to non-linear and organic thinking, more commonly referred to as systems thinking. System Dynamics, which operates in a whole-system fashion, is put forward as a powerful methodology to deal with issues of sustainability. Examples of successful applications are given. Any system in which humans are involved is characterized by the following essential system properties: Bounded rationality, limited certainty, limited predictability, indeterminate causality, and evolutionary change. We need to resort to an adaptive approach, where we go through a learning process and modify our decision rules and our mental models of the real world as we go along. This will enable us to improve system performance by setting dynamic improvement goals (moving targets) for it. Finally, it is demonstrated how causal loop diagrams can be used to find the leverage points of a system.
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| 12. |
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| 13. |
- Hjorth, Peder, et al.
(author)
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Systems Analysis to Promote Frames and Mental Models for Sustainable Water Management
- 2013
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In: Sciforum Electronic Conference Series. - Basel, Switzerland : MDPI. ; 3
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Conference paper (peer-reviewed)abstract
- In the water sector, there have been numerous failures in projects aiming at sustainable development and there have been some, but less numerous, examples of successes. However, the most striking observation is the near universal failure to learn from these examples. Somehow, scientists and decision makers have allowed the indications of new approaches and opportunities go undetected because they did not fit with their mindsets or perceptual apparatus. This paper discusses some of the mental frames that have hampered the progress towards sustainable development. It analyzes where these frames come from, who is promoting or defending them, and what can be done to change these frames in ways that are more in line with the basic tenets of sustainable development. It is found that there is a lack of consistency in the interpretation of sustainable development. Most sustainability initiatives have failed because the environment and development were never properly brought together. The “environment” is where we live: and “development” is what we all do in attempting to improve our lot within that abode. The two are unseparable (Our Common Future). Thus, there is a need to draw on diverse disciplinary perspectives and to cut across sectoral boundaries to counter the monovalent approaches that have dominated mainstream enquiry and practice. To that end, systems analysis can help produce enabling frameworks for process changes. These frameworks should define general objectives and means of verification of progress without specifying uniform approaches and activities. Systems analysis is also a methodology helping to make sure that problems posed are adequately defined and that helps detecting biases in goal formulation stemming either from dominant actors or from “solution oriented approaches”.
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| 14. |
- Hjorth, Peder
(author)
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Towards Sustainable Urban Water and Sanitation Services: Barriers and Bridges
- 2009
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In: Sustainability. - : MDPI AG. - 2071-1050. ; 1:4, s. 1023-1034
-
Journal article (peer-reviewed)abstract
- The Mar del Plata International Water Conference provided the first global assessment of the water sector. It was found that in most developing countries the state of water supply and sanitation services were deplorable. Consequently, a call for concerted action to improve coverage and efficiency of the water supply and sanitation sector was launched. This call resulted in the International Water Supply and Sanitation Decade (1981–1990). The Decade provided important lessons concerning effective methodologies to improve the state of the WSS sector. The paper discusses why the poor state of the water supply and sanitation conditions still tend to be the greatest development failure during the 20th century. The recipe for success was there, and the money was there. So, why were governments and big donors like the World Bank refusing to apply the lessons from the Decade? The basic conditions for success are spelled out, and some successful cases are used to illustrate these. The conclusion is that change is possible but that civil society organizations have to be empowered to make governments "feel the heat" and spend more money on water and sanitation, and to spend it more wisely.
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| 15. |
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| 16. |
- Holm-Waters, Susanna, et al.
(author)
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Preclinical Pharmacology of 2-(3-Fluoro-5-Methanesulfonyl-phenoxy)Ethyl (Propyl)amine (IRL790), a Novel Dopamine Transmission Modulator for the Treatment of Motor and Psychiatric Complications in Parkinson Disease
- 2020
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In: Journal of Pharmacology and Experimental Therapeutics. - : American Society for Pharmacology & Experimental Therapeutics (ASPET). - 0022-3565 .- 1521-0103. ; 374:1, s. 113-125
-
Journal article (peer-reviewed)abstract
- IRL790 ([2-(3-fluoro-5-methanesulfonylphenoxy)ethyl](propyl)amine, mesdopetam) is a novel compound in development for the clinical management of motor and psychiatric disabilities in Parkinson disease. The discovery of IRL790 was made applying a systems pharmacology approach based on in vivo response profiling. The chemical design idea was to develop a new type of DA D3/D2 receptor type antagonist built on agonist rather than antagonist structural motifs. We hypothesized that such a dopamine antagonist with physicochemical properties similar to agonists would exert antidyskinetic and antipsychotic effects in states of dysregulated dopaminergic signaling while having little negative impact on physiologic dopamine transmission and, hence, minimal liability for side effects related to dopamine-dependent functions. At the level of in vivo pharmacology, IRL790 displays balancing effects on aberrant motor phenotypes, reducing L-DOPA-induced dyskinesias in the rodent 6-hydroxydopamine lesion model and reducing psychostimulant-induced locomotor hyperactivity elicited by pretreatment with either d-amphetamine or dizocilpine, without negatively impacting normal motor performance. Thus, IRL790 has the ability to normalize the behavioral phenotype in hyperdopaminergic as well as hypoglutamatergic states. Neurochemical and immediate early gene (IEG) response profiles suggest modulation of DA neurotransmission, with some features, such as increased DA metabolites and extracellular DA, shared by atypical antipsychotics and others, such as increased frontal cortex IEGs, unique to IRL790. IRL790 also increases extracellular levels of acetylcholine in the prefrontal cortex and ventral hippocampus. At the receptor level, IRL790 appears to act as a preferential DA D3 receptor antagonist. Computational docking studies support preferential affinity at D3 receptors with an agonist-like binding mode. SIGNIFICANCE STATEMENT This paper reports preclinical pharmacology along with molecular modeling results on IRL790, a novel compound in clinical development for the treatment of motor and psychiatric complications in advanced Parkinson disease. IRL790 is active in models of perturbed dopaminergic and glutamatergic signaling, including rodent 6-hydroxydopamine L-DOPA-induced dyskinesias and psychostimulant-induced hyperactivity, in a dose range that does not impair normal behavior. This effect profile is attributed to interactions at dopamine D2/D3 receptors, with a 6- to 8-fold preference for the D3 subtype.
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| 17. |
- Juizo, Dinis, et al.
(author)
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Application of a district management approach to Southern African river basin systems: the case of the Umbeluzi, Incomati and Maputo river basins
- 2009
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In: Water Policy. - : IWA Publishing. - 1366-7017 .- 1996-9759. ; 11:6, s. 719-730
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Journal article (peer-reviewed)abstract
- In recent years, the 'river basin as a management unit' approach has been adopted as a solution to water management. The situation between Swaziland, Mozambique and South Africa regarding managing the water resources of the Incomati, Maputo, and Umbeluzi shared river basins is an interesting case that might need a different approach. These rivers flow downstream to the Maputo estuary where their waters are needed for urban water supply (Maputo city) and fresh water pulses for the estuary. The Incomati and Umbeluzi are heavily committed upstream while the Maputo appears still to have a relative abundance of untapped water resources. At basin level, the three countries fail to reach a consensus on the best strategies to accommodate multiple demands, particularly in the downstream area. The IncoMaputo agreement that was concluded by the three governments is unique in that it comprises two basins (Maputo and Incomati), allowing a multi-basin approach to the problem. However, the Umbeluzi was left out of the agreement. This paper discusses the possible benefits of a multi-basin approach to water resources for the three rivers discharging into Espirito Santo Estuary in Maputo. Using the provisions set out in the European Union Water Framework Directive (WFD) it is found that the three rivers of this study may well be suitable for implementing the District Water Management approach as proposed in the WFD.
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| 18. |
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| 19. |
- Kalteh, Aman Mohammad, et al.
(author)
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Imputation of missing values in a precipitation-runoff process database
- 2009
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In: Hydrology Research. - : IWA Publishing. - 1998-9563 .- 0029-1277 .- 2224-7955. ; 40:4, s. 420-432
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Journal article (peer-reviewed)abstract
- Hydrologists are often faced with the problem of missing values in a precipitation-runoff process database to construct runoff prediction models. They tend to use simple and naive methods to deal with the problem of missing data. Thus far, the common practice has been to discard observations with missing values. In this paper, we present some statistically principled methods for gap filling and discuss the pros and cons of these methods. We employ and discuss imputations of missing values by means of self-organizing map (SOM), multilayer perceptron (MLP), multivariate nearest-neighbor (MNN), regularized expectation-maximization algorithm (REGEM) and multiple imputation (MI) in the context of a precipitation-runoff process database in northern Iran in order to construct a serially complete database for analyses such as runoff prediction. In our case, the SOM and MNN tend to give similar and robust results. REGEM and MI build on the assumption of multivariate normal data, which we don't seem to have in one of our cases. MLP tends to produce inferior results because it fragments the data into 68 different models. Therefore, we conclude that it makes most sense to use either the computationally simple MNN method or the more demanding SOM.
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| 20. |
- Kalteh, Aman Mohammad, et al.
(author)
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Review of the self-organizing map (SOM) approach in water resources: Analysis, modelling and application
- 2008
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In: Environmental Modelling & Software. - : Elsevier BV. - 1364-8152. ; 23:7, s. 835-845
-
Research review (peer-reviewed)abstract
- The use of artificial neural networks (ANNs) in problems related to water resources has received steadily increasing interest over the last decade or so. The related method of the self-organizing map (SOM) is an unsupervised learning method to analyze, cluster, and model various types of large databases. There is, however, still a notable lack of comprehensive literature review for SOM along with training and data handling procedures, and potential applicability. Consequently, the present paper aims firstly to explain the algorithm and secondly, to review published applications with main emphasis on water resources problems in order to assess how well SOM can be used to solve a particular problem. It is concluded that SOM is a promising technique suitable to investigate, model, and control many types of water resources processes and systems. Unsupervised learning methods have not yet been tested fully in a comprehensive way within, for example water resources engineering. However, over the years, SOM has displayed a steady increase in the number of applications in water resources due to the robustness of the method.
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