Ecosystem properties and principles of living systems as foundation for sustainable agriculture – Critical reviews of environmental assessment tools, key findings and questions from a course process

With increasing demands on limited resources worldwide, there is a growing interest in sustainable patterns of utilisation and production. Ecological agriculture is a response to these concerns. To assess progress and compliance, standard and comprehensive measures of resource requirements, impacts and agro-ecological health are needed. Assessment tools should also be rapid, standardized, userfriendly, meaningful to public policy and applicable to management. Fully considering these requirements confounds the development of integrated methods. Currently, there are many methodologies for monitoring performance, each with its own foundations, assumptions, goals, and outcomes, dependent upon agency agenda or academic orientation. Clearly, a concept of sustainability must address biophysical, ecological, economic, and sociocultural foundations. Assessment indicators and criteria, however, are generally limited, lacking integration, and at times in conflict with one another. A result is that certification criteria, indicators, and assessment methods are not based on a consistent, underlying conceptual framework and often lack a management focus. Ecosystem properties and principles of living systems, including self-organisation, renewal, embeddedness, emergence and commensurate response provide foundation for sustainability assessments and may be appropriate focal points for critical thinking in an evaluation of current methods and standards. A systems framework may also help facilitate a comprehensive approach and promote a context for meaningful discourse. Without holistic accounts, sustainable progress remains an illdefined concept and an elusive goal. Our intent, in the work with this report, was to use systems ecology as a pedagogic basis for learning and discussion to: - Articulate general and common characteristics of living systems. - Identify principles, properties and patterns inherent in natural ecosystems. - Use these findings as foci in a dialogue about attributes of sustainability to: a. develop a model for communicating scientific rationale. b. critically evaluate environmental assessment tools for application in land-use. c. propose appropriate criteria for a comprehensive assessment and expanded definition of ecological land use

PS - a school-wide prevention programme : effects, core components and implementation.

PS is multi-component intervention at the primary prevention level and aims at creating a positive learning environment and decreasing problem behaviours among students in the school years 4-9. During 2009-2012 the programme was both implemented and studied for the first time in a Swedish context. The present thesis comprises four studies of PS and applies a mixed methods approach. The thesis aims to study: 1) If the programme is effective in enhancing the classroom climate, and decreasing problem behaviours among students (Study I), 2) teachers and school staff’s perceptions of programme and implementation (study II and III) and 3) if teacher’s use of praise and clarity of school rules, regardless of programme use, are useful as classroom management techniques, and if there are any differences between classes in terms of disruption (study IV). A quasi-randomized trial was conducted in study I, comprising 3207 students in school grades 5-7 and 188 teachers in 23 schools in the wider area of Stockholm. The participating children and their head teachers answered self-report questionnaires on three occasions: At baseline and one and two years after programme initiation. Degree of implementation in the schools was also measured. Further, a qualitative design with semi-structured interviews and thematic content analysis was used in study II and III. The interviews were conducted in seven PS schools with seven school leaders and 13 school teachers during 2010 and 2011. In study IV, students (n=2266) and classes were divided into two groups, based on teacher ratings of disruptive students in class. Baseline and 12-month follow-up responses were used to perform multiple regression analysis, to compare groups and to investigate possible longitudinal associations. Study I showed no significant effects on students’ problem behaviours and classroom climate at last follow-up. The findings from study II indicated barriers to programme commitment in terms of lack of consensus, collaboration barriers and insufficient process management. It was concluded that leadership, coaching and staff selection need particular attention when implementing a programme like PS, since those factors have been defined as important implementation drivers, both in this study and previously. Study III showed that teachers’ professional identity, programme understanding and experience of change were factors affecting implementation. Ambiguities regarding the boundaries of the social assignment, opposition against the theoretical underpinnings and an unclear core component were identified as implementation barriers. In study IVit was shown that clarity of school rules did not substantially contribute to classroom climate, whereas teacher’s use of praise to some extent did. The hypothesis on weaker associations in the low disruption group could not be confirmed. This thesis cannot provide an answer to the question whether PS is effective or not, since findings indicate that the implementation did not succeed. However, findings in the last study indicate that teacher’s use of praise may contribute to improve the classroom climate. If the PS programme is to be used again there is a need for revisions, and sufficient time for schools to consider programme adoption will be crucial. Aspects of programme implementation are further discussed

Equilibrium model selection: dTTP induced R1 dimerization

<p>Abstract</p> <p>Background</p> <p>Biochemical equilibria are usually modeled iteratively: given one or a few fitted models, if there is a lack of fit or over fitting, a new model with additional or fewer parameters is then fitted, and the process is repeated. The problem with this approach is that different analysts can propose and select different models and thus extract different binding parameter estimates from the same data. An alternative is to first generate a comprehensive standardized list of plausible models, and to then fit them exhaustively, or semi-exhaustively.</p> <p>Results</p> <p>A framework is presented in which equilibriums are modeled as pairs (<it>g</it>, <it>h</it>) where <it>g </it>= 0 maps total reactant concentrations (system inputs) into free reactant concentrations (system states) which <it>h </it>then maps into expected values of measurements (system outputs). By letting dissociation constants <it>K</it>_{<it>d </it>}be either freely estimated, infinity, zero, or equal to other <it>K</it>_<it>d</it>, and by letting undamaged protein fractions be either freely estimated or 1, many <it>g </it>models are formed. A standard space of <it>g </it>models for ligand-induced protein dimerization equilibria is given. Coupled to an <it>h </it>model, the resulting (<it>g</it>, <it>h</it>) were fitted to dTTP induced R1 dimerization data (R1 is the large subunit of ribonucleotide reductase). Models with the fewest parameters were fitted first. Thereafter, upon fitting a batch, the next batch of models (with one more parameter) was fitted only if the current batch yielded a model that was better (based on the Akaike Information Criterion) than the best model in the previous batch (with one less parameter). Within batches models were fitted in parallel. This semi-exhaustive approach yielded the same best models as an exhaustive model space fit, but in approximately one-fifth the time.</p> <p>Conclusion</p> <p>Comprehensive model space based biochemical equilibrium model selection methods are realizable. Their significance to systems biology as mappings of data into mathematical models warrants their development.</p

DNA building blocks: keeping control of manufacture

Ribonucleotide reductase (RNR) is the only source for de novo production of the four deoxyribonucleoside triphosphate (dNTP) building blocks needed for DNA synthesis and repair. It is crucial that these dNTP pools are carefully balanced, since mutation rates increase when dNTP levels are either unbalanced or elevated. RNR is the major player in this homeostasis, and with its four different substrates, four different allosteric effectors and two different effector binding sites, it has one of the most sophisticated allosteric regulations known today. In the past few years, the structures of RNRs from several bacteria, yeast and man have been determined in the presence of allosteric effectors and substrates, revealing new information about the mechanisms behind the allosteric regulation. A common theme for all studied RNRs is a flexible loop that mediates modulatory effects from the allosteric specificity site (s-site) to the catalytic site for discrimination between the four substrates. Much less is known about the allosteric activity site (a-site), which functions as an on-off switch for the enzyme's overall activity by binding ATP (activator) or dATP (inhibitor). The two nucleotides induce formation of different enzyme oligomers, and a recent structure of a dATP-inhibited α6β2 complex from yeast suggested how its subunits interacted non-productively. Interestingly, the oligomers formed and the details of their allosteric regulation differ between eukaryotes and Escherichia coli Nevertheless, these differences serve a common purpose in an essential enzyme whose allosteric regulation might date back to the era when the molecular mechanisms behind the central dogma evolved

Petiole hyponasty: an ethylene-driven, adaptive response to changes in the environment

Hyponastic (upwardly bending) growth by leaves is a response of numerous plant species to adverse environmental conditions. This review summarises current knowledge on hyponasty with a particular focus on the role of ethylene in regulating this phenomenon and its possible adaptive significance

Forest tenure in Sweden

Land tenure regimes are intimately coupled to land use forms, and tenure reforms accompany the ongoing re-evaluation of forest management around the globe. This report summarises forest tenure development in Sweden during the last 500 years. The driving forces of privatisation in Swedish forestry are seen in relation to the modernisation of society. The current forest ownership structure reflects the objectives of privatisation of forestland two hundred years ago. The Crown wished to provide every homestead with enough forest to cover it subsistence needs for major and minor forest products. The privatisation process gained momentum around 1800, well before the industrial revolution gave forestry commercial value. As there was little use for the vast timber re-source, other than for household purposes, the Crown initially did not bother to define exact user rights. The transition in the North of Sweden is one example where the state did not foresee any conflict, as forestry, farming and reindeer herding were considered to co-exist. The first period of the privatisation process was turbulent when the full consequences of the transition from forest commons for subsistence to an exploit-table natural resource became obvious. Corporate law infringements, dubious affairs, fraud, and exploitation of peasant land-owners occurred, and much of the accessible forestland was temporarily ruined. Once secure in their tenure, the peasants started exploiting the now valuable timber resource, then, more reluctantly, began to employ modern management methods in spite of the extremely long investment horizon in northern silviculture. Today, Sweden appears to have reached an “age of maturity” regarding forest ownership, with a modern tenure system that requires an open dialogue between forest owners and stakeholders and considering multiple user rights. Private ownership of forest is a contributing factor to the success of the “Nordic Forestry Model”, and experiences from the tenure development in the Nordic countries have a broader application for global forest policy

Small-scale forestry in Sweden

The purpose of the thesis was to improve the tools for decision making for small-scale forest owners in Sweden. Understanding the objectives of forest owners is crucial for the success of policy initiatives and for promoting successful sustainable forest management. The aims of this thesis were to: a) depict the green forest management plan from a nature conservation point of view; b) identify objectives of owners’; c) analyse different types of owners; and d) evaluate the suitability of silvicultural practices for fulfilling multiple objectives. The link between the policies at different levels – the inventory instruction – the counselling – the management plan and the forest owners was studied. Discriminant analysis was used to study the professional foresters’ choice of areas set aside for nature conservation. A theoretical model for empirical studies of objectives was constructed. Explorative qualitative interviews with foresters and forest owners were conducted, followed by a quantitative study using cluster analysis to identify different types of forest owners. A literature review was undertaken to study silvicultural practices, followed by an analysis of the relationships with the objectives. In addition, a method for evaluating results of research within the field was presented. The results showed that the contact between professional foresters and the forest owner is a weak point during the production of the plan. Economic consideration was not the major consideration for the planners in the selection of nature conservation compartments in the Green forest management plan. The objectives and motivations of small-scale forest owners of today covered a broad field from nature conservation to tax planning. The four motivations depicted during the interviews were ‘conservation’, ‘utilities’, ‘amenities’ and ‘economic efficiency’. The following sub-groups of forest owners were differentiated from the quantitative data: ‘the economist’, ‘the conservationist’, ‘the traditionalist’, ‘the optimist’ and finally ‘the pessimist’. The results also indicated that thinning, different forms of natural regeneration and cleaning are useful practices, whereas ‘passive practices’ seem to be unsuitable for multipurpose objectives. Although the results show that forest owners can be differentiated by their objectives, more importantly the results show that precise individual silvicultural programmes can be created for each owner