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101.
Joakim Hjältén Anna Lindau Anders Wennström Patrik Blomberg Johanna Witzell Lars Ericson 《Chemoecology》2008,18(4):227-231
Summary. There is an increased interest for the use of GM trees in forestry and several commercially promising lines are now available.
However, the ecological implications of the use of GM trees, e.g. effects on non-target natural enemies, have rarely been
explored. The aim of this study was to determine if modification of non-defensive traits in GM poplars unintentionally can
influence plant chemistry in a way that has consequences for palatability to voles. In a greenhouse experiment, we used two
lines, SPS33A and SPS26, of GM hybrid poplars (Populus tremula x tremuloides) with 1.5 and 4 times, respectively, over-expression sucrose-phosphate synthase (SPS). This enzyme plays a central role in
sucrose synthesis, affecting cold acclimation, mesophyll sucrose content and biomass production. As a control we used the
isogenic unmodified wild type. Stems of these poplars were presented to bank voles and field voles in cafeteria experiments.
The concentration of condensed tannins was higher in leaves of lines SPS33A and SPS26 than in the isogenic wild-type and the
concentration of nitrogen was higher in line SPS33A than in both the wild-type and line SPS26. Although the bank voles consumed
slightly less bark from SPS33A, there were no significant differences in the preference of bank vole or field vole for the
different poplar lines. This indicates that the changes in plant chemistry were insufficient to produce any strong herbivore
response or that alteration in tannins and nitrogen counteracted each other. Still, changes in the interactions between mammalian
herbivores and GM trees are important to consider in future cost-benefits analyses of GM trees. 相似文献
102.
Judith Schleicher Johanna Eklund Megan D. Barnes Jonas Geldmann Johan A. Oldekop Julia P. G. Jones 《Conservation biology》2020,34(3):538-549
The awareness of the need for robust impact evaluations in conservation is growing and statistical matching techniques are increasingly being used to assess the impacts of conservation interventions. Used appropriately matching approaches are powerful tools, but they also pose potential pitfalls. We outlined important considerations and best practice when using matching in conservation science. We identified 3 steps in a matching analysis. First, develop a clear theory of change to inform selection of treatment and controls and that accounts for real-world complexities and potential spillover effects. Second, select the appropriate covariates and matching approach. Third, assess the quality of the matching by carrying out a series of checks. The second and third steps can be repeated and should be finalized before outcomes are explored. Future conservation impact evaluations could be improved by increased planning of evaluations alongside the intervention, better integration of qualitative methods, considering spillover effects at larger spatial scales, and more publication of preanalysis plans. Implementing these improvements will require more serious engagement of conservation scientists, practitioners, and funders to mainstream robust impact evaluations into conservation. We hope this article will improve the quality of evaluations and help direct future research to continue to improve the approaches on offer. 相似文献
103.
Jennifer Zavaleta Cheek Johanna Eklund Nikolas Merten Jeremy Brooks Daniel C. Miller 《Conservation biology》2023,37(4):e14071
Knowledge of what conservation interventions improve biodiversity outcomes, and in which circumstances, is imperative. Experimental and quasi-experimental methods are increasingly used to establish causal inference and build the evidence base on the effectiveness of interventions, but their ability to provide insight into how and under what conditions an intervention should be implemented to improve biodiversity outcomes faces limitations. A suite of attribution methods that leverage qualitative methods for causal inference is available but underutilized in conversation impact evaluation. This article provides a guide to 5 such qualitative attribution methods: contribution analysis, process tracing, realist evaluation, qualitative comparative analysis, and most significant change. It defines and introduces each method and then illustrates how they could be applied through a case study of community conservancies in Namibia. This guide provides examples of how qualitative attribution methods can advance knowledge of what works, in which contexts, and why in biodiversity conservation. 相似文献
104.
This paper systematically reviews the literature on how to reduce nutrient emissions to the Baltic Sea cost-effectively and considerations for allocating these costs fairly among countries. The literature shows conclusively that the reduction targets of the Baltic Sea Action Plan (BSAP) could be achieved at considerably lower cost, if countries would cooperate to implement the least costly abatement plan. Focusing on phosphorus abatement could be prudent as the often recommended measures—wastewater treatment and wetlands—abate nitrogen too. An implication of our review is that the potential for restoring the Baltic Sea to good health is undermined by an abatement strategy that is more costly than necessary and likely to be perceived as unfair by several countries. Neither the BSAP nor the cost-effective solution meet the surveyed criteria for fairness, implying a need for side-payments.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01580-4. 相似文献
105.
The strongly nucleophilic cob(I)alamin, i.e. Vitamin B12 with Co(III) reduced to Co(I), is introduced as a trapping agent in the determination of concentrations of electrophilic reagents. This compound was applied, in comparison with the previously used moderately reactive nicotinamide (H.J.C.F. Nelis and J.E. Sinsheimer (1981). Anal. Biochem., 115, 151.). Oxiranes, metabolites of 1-alkenes, were chosen as model electrophiles. The reagents (nicotinamide and cob(I)alamin) were evaluated in the determination of the rates of reaction toward valine methylamide, a model of N-terminal valines in hemoglobin often used for monitoring of doses in vivo of genotoxic carcinogens. The rate constants for reaction at 37°C with valine methylamide (k VMA) determined by the cob(I)alamin and nicotinamide procedure, respectively, were for ethylene oxide (1.6, 1.7), propylene oxide (0.9, 1.1), 1,2-epoxybutane (0.7, 0.8) and 1,2-epoxyoctane (0.5, 0.6) M?1?h?1, decreasing with increasing number of carbons of the oxirane. Concentrations of oxiranes trapped with nicotinamide are underrated in reaction mixtures containing valine methylamide due to consumption by reaction with the competing nucleophile, a disturbance that is not observed in trapping with cob(I)alamin which reacts about 105 times faster than nicotinamide. Cob(I)alamin which was demonstrated to be an efficient nucleophile for trapping of electrophiles, also in the presence of competing nucleophiles, is promising as an analytical tool in toxicological studies of reactive compounds. Furthermore, cob(I)alamin can be used to detect, measure and compare electrophilic reactivity of chemical substances, a property that is associated with genotoxic potency. 相似文献
106.
Claudie Doums Camille Ruel Johanna Clémencet Pierre Fédérici Laurent Cournault Serge Aron 《Behavioral ecology and sociobiology》2013,67(12):1983-1993
Under the hymenopteran single-locus complementary sex-determination system, production of diploid males results from homozygosity at the sex-determiner locus. This arises when both parents transmit identical alleles at the locus to the offspring. In species reproducing asexually through thelytokous parthenogenesis, production of diploid males may also occur when the sex locus undergoes recombination and becomes homozygous in the offspring. Diploid males represent a substantial genetic load in hymenopteran populations because they often produce unviable sperm or sire sterile triploid female offspring. In the Mediterranean ant Cataglyphis cursor, the queen and workers can produce female offspring through automictic thelytokous parthenogenesis with central fusion, a mode of parthenogenesis that increases homozygosity. We report, for the first time, the presence of about 39 % of colonies producing adult diploid males (seven colonies out of 18). Overall, 8 % of adult males were diploid (12 diploid males out of the 146 males genotyped). Genotyping workers from the seven colonies producing diploid males showed that three diploid males were sons of queens and produced by thelytoky, six were probably sons of workers also produced by thelytoky and three were non-natal. Furthermore, the mating of a diploid male with two virgin queens in the laboratory led to the production of sterile triploid workers, which shows that diploid males in C. cursor are fertile, mate successfully and produce viable and functional but probably sterile female offspring. Because diploid males originate from thelytokous reproduction, they are only produced during sexual production and hence do not impair colony growth, which could explain why they are not removed at early brood stages. 相似文献
107.
Jill K. Tjon Melinda M. E. H. Witbreuk Peter A. A. Struijs Bloeme J. van der Knoop Ingeborg H. Linskens Johanna I. P. de Vries 《黑龙江环境通报》2023,43(8):1056-1065
Objective
Children and adults with talipes equinovarus (TEV) have smaller calves and shorter feet compared to non-affected controls. Do these changes have a prenatal onset?Methods
A prospective cohort study (January 2020–July 2021) was conducted with serial ultrasonographic measurements at 20 and 28 weeks gestation and measurements directly and 6 weeks after birth. Calf circumference and width, foot length and length of humerus, ulna, radius, femur, tibia and fibula were measured in TEV and were compared to a control population. Calculated sample size necessitated a minimal population of 10 cases with TEV and 50 controls.Results
Twenty cases with TEV and 62 controls were included. Fetal calf circumference (p < 0.001) and width (p < 0.001) were smaller in the TEV group in comparison to the control group, which persisted after birth. Growth in foot length (p < 0.001) and calf width (p 0.003) declined prenatally over time. The bone lengths and upper leg circumference were not smaller or shorter in TEV compared to controls.Conclusion
This prospective cohort study demonstrated the prenatal onset of reduced calf and foot size in fetuses with TEV from 20 weeks and onwards, which persists directly after birth. To investigate whether reduction in circumference initiates TEV or is caused by TEV, further examination is needed. 相似文献108.
Olivier Hatem Sander Kamel Frank Jacques-Eric Jacques Thomas Johanna Alkan Delphine Martin 《Environmental Science & Policy》2009,12(5):619-630
Scenario-based approaches in environmental and policy assessment studies are increasingly applied within integrated assessment and modelling frameworks. The SEAMLESS project develops such an integrated framework (SEAMLESS-IF) aiming to assess, ex-ante, impacts of alternative agro-environmental policies on the sustainability of agricultural systems. A particular challenge in this context is the consistent translation of a wide range of policy questions into scenarios that a modelling framework can assess. The present work defines a methodology for scenario-development in integrated policy assessment with specific emphasis on SEAMLESS-IF. After a general overview on scenario concepts for integrated policy assessment the adopted scenario concept and its development procedure is presented. They allow building integrated scenarios capturing the range of drivers of the assessed agricultural system in a consistent way across temporal and spatial scales. Then focus is on the particular procedures to translate the policy assessment questions into scenario parameters and to implement these parameters into SEAMLESS-IF. Two examples targeted at European and regional level combining integrated assessments of policy changes and technological innovations are considered to illustrate the SEAMLESS scenario concept. We conclude that the proposed methodology to translate policy assessment problems into scenarios effectively supports integrated assessment in SEAMLESS-IF or even in other modelling frameworks. 相似文献
109.
ABSTRACTSmart and eco-cities have become important notions for thinking about urban futures. This article contributes to these ongoing debates about smart and eco-urbanism by focussing on recent urbanisation initiatives in Asia. Our study of India’s Smart Cities Mission launched under the administration of Narendra Modi and China’s All-In-One eco-cities project initiated by Xi Jinpin unfolds in two corresponding narratives. Roy and Ong’s [2011. Worlding Cities: Asian Experiments and the Art of Being Global. Oxford: Wiley-Blackwell] “worlding cities” serves as the theoretical backdrop of our analysis. Based on a careful review of a diverse set of academic literature, policy and other sources we identify five process-dimensions for analysing the respective urban approaches. We show how the specific features of China’s and India’s urban focus, organisation, implementation, governance and embedding manifest both nations’ approaches to smart and eco-urbanism. We argue that India’s Smart City Mission and China’s All-in-One project are firmly anchored in broader agendas of change that are set out to transform the nation and extend into time. The Indian Smart City Mission is part of a broader ambition to transform the nation enabling her “smart incarnation” in modernity. Smart technologies are seen as the key drivers of change. In China the framework of ecological civilisation continues a 5000-year historical tradition of civilisation excellence. By explicitly linking eco-urbanism to the framework, eco-cities become a means to enact ecological civilisation on the (urban) ground. 相似文献
110.
The Nottingham Cycle Friendly Employers Project studied the effectiveness of measures to promote cycling to work by eight large city employers under the 1995 governmentfunded Cycle Challenge. Progress was monitored by ‘before’ and ‘after’ surveys, by examination of the measures, and by discussions with the employers. Overall cycling awareness and activity were increased by the project: 42% of employees said their cycle commuting had increased. The main influences, about equally, were providing workplace cycling facilities, a house or job move making cycling more attractive, and heightened awareness of the importance of regular exercise for health. The most welcomed and best used measures were secure cycle parking, showering and changing facilities, and cycle purchase loans. 相似文献