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1.
“Beyond GDP” initiatives flag the limits of the quantitative indicators of progress currently used for governance. Focusing on the quality assessment of quantitative information used for governance, we use some of the conceptual tools of theoretical ecology and evolutionary biology in order to identify the pre-analytical choices that determine the usefulness and pertinence of a model. Starting from the definition of a model as a formal representation of a specific and necessarily subjective observation, we show that the production of indicators is the final result of a series of decisions on what to observe and how. These choices, in turn, depend on the narrative, or set of narratives, adopted. Narratives provide causality and context to knowledge claims and are needed to select the indicators to be used for policy. Moving beyond the GDP debate requires reflexivity, that is, awareness of the key role that pre-analytical choices play in the definition of both the relevance of the chosen perceptions and narratives (determined by the normative stands of different actors – who defines wellbeing?), and the usefulness of the chosen models and data (determined by the pertinence of the resulting representation – how to measure wellbeing?). Reflexivity is essential in order to take into account the purposes for which different indicators were created and to define new purposes for the “beyond GDP” indicators.  相似文献   
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Prospective life cycle assessment (LCA) needs to deal with the large epistemological uncertainty about the future to support more robust future environmental impact assessments of technologies. This study proposes a novel approach that systematically changes the background processes in a prospective LCA based on scenarios of an integrated assessment model (IAM), the IMAGE model. Consistent worldwide scenarios from IMAGE are evaluated in the life cycle inventory using ecoinvent v3.3. To test the approach, only the electricity sector was changed in a prospective LCA of an internal combustion engine vehicle (ICEV) and an electric vehicle (EV) using six baseline and mitigation climate scenarios until 2050. This case study shows that changes in the electricity background can be very important for the environmental impacts of EV. Also, the approach demonstrates that the relative environmental performance of EV and ICEV over time is more complex and multifaceted than previously assumed. Uncertainty due to future developments manifests in different impacts depending on the product (EV or ICEV), the impact category, and the scenario and year considered. More robust prospective LCAs can be achieved, particularly for emerging technologies, by expanding this approach to other economic sectors beyond electricity background changes and mobility applications as well as by including uncertainty and changes in foreground parameters. A more systematic and structured composition of future inventory databases driven by IAM scenarios helps to acknowledge epistemological uncertainty and to increase the temporal consistency of foreground and background systems in LCAs of emerging technologies.  相似文献   
4.
The copy frequency distribution of a transposable element family in a Drosophila melanogaster natural population is generally characterised by the values of the Charlesworths' model parameters α and β (Charlesworth & Charlesworth, 1983). The estimation of these parameters is made using the observed distribution of the occupied sites in a population sample. Several results have been interpreted as due either to the influence of stochastic factors or to deterministic factors (transposition, excision, selection…). The accuracy of this method was tested by estimations performed on samples from simulated populations. The results show that with the sample size usually used for natural population studies, the confidence intervals are too large to reasonably deduce either the element copy number distribution or the values of transposition and excision rate and selective coefficients.  相似文献   
5.
Stimulation of the neonatal immune system is quite important for the proliferation and differentiation of antigen-presenting cells (APCs) and T cells. Tahneeq is a traditional method to manually rub the palatal mucosa of newborn babies with premasticated Ajwa palm dates. The present study was to investigate the tahneeq effects on IL-12 expression of dendritic cells (DCs) and blood T lymphocytes expressing CD8+ in neonatal Wistar rats. The number of 90 healthy neonatal Wistar rats have randomly divided into three groups: control group received breastmilk only, treatment group (T1) receiving breast milk + mild-scratched intensity of tahneeq, and T2 group received breastmilk + strong-scratched intensity of tahneeq on the palatal and gingival mucosa immediately after birth.  Seven neonatal Wistar rats in all groups were then sacrificed in three hours after birth and days 1, 5, 7, 13, and 30 treatment. IL-12 expression in the palatal and gingival mucosa was determined using immunohistochemical staining, and blood CD8+ T-lymphocytes were quantified using a flow cytometer. One way ANOVA was used to analyze the percentage of IL-12 and CD8+ T-lymphocytes among neonatal Wistar rat groups.  The T1 and T2 newborn rat groups had significantly higher IL-12 expression than the control group (p<0.001). The increased IL-12 expression in T2 groups significantly increased (p<0.001) compared to the IL-12 expression in the T1 and control groups. The percentage of  CD8+ T lymphocytes in all neonatal rat groups increased on three hours after birth and day 30 treatment but remained constant on days 5 and 7 treatment and decreased on day 13 treatment. At 5, 13, and 30th days treatment,  the percentage of CD8+ T lymphocytes in T1 and T2 neonatal rat groups was significantly higher (p<0.05) than that in the control group. In conclusion, the impact on systemic CD8+ T cells did not influence by the depth of the scratch. Both mild and strong tahneeq increased the systemic CD8+ T-lymphocytes in neonatal Wistar rats. The roles of anti-inflammatory cytokines and Treg cells should be further investigated to unravel those different results for the development of mucosal immunity in neonates.  相似文献   
6.
Medial knee osteoarthritis is a debilitating disease. Surgical and conservative interventions are performed to manage its progression via reduction of load on the medial compartment or equivalently its surrogate measure, the external adduction moment. However, some studies have questioned a correlation between the medial load and adduction moment. Using a musculoskeletal model of the lower extremity driven by kinematics–kinetics of asymptomatic subjects at gait midstance, we aim here to quantify the relative effects of changes in the knee adduction angle versus changes in the adduction moment on the joint response and medial/lateral load partitioning. The reference adduction rotation of 1.6° is altered by ±1.5° to 3.1° and 0.1° or the knee reference adduction moment of 17 N m is varied by ±50% to 25.5 N m and 8.5 N m. Quadriceps, hamstrings and tibiofemoral contact forces substantially increased as adduction angle dropped and diminished as it increased. The medial/lateral ratio of contact forces slightly altered by changes in the adduction moment but a larger adduction rotation hugely increased this ratio from 8.8 to a 90 while in contrast a smaller adduction rotation yielded a more uniform distribution. If the aim in an intervention is to diminish the medial contact force and medial/lateral load ratio, a drop of 1.5° in adduction angle is much more effective (causing respectively 12% and 80% decreases) than a reduction of 50% in the adduction moment (causing respectively 4% and 13% decreases). Substantial role of changes in adduction angle is due to the associated alterations in joint nonlinear passive resistance. These findings explain the poor correlation between knee adduction moment and tibiofemoral compartment loading during gait suggesting that the internal load partitioning is dictated by the joint adduction angle.  相似文献   
7.
《Journal of biomechanics》2014,47(15):3734-3743
In this study, a three-dimensional finite element model was used to investigate the changes in tissue composition and mechanical signals within human lumbar intervertebral disc during the degenerative progression. This model was developed based on the cell-activity coupled mechano-electrochemical mixture theory. The disc degeneration was simulated by lowering nutrition levels at disc boundaries, and the temporal and spatial distributions of the fixed charge density, water content, fluid pressure, Von Mises stress, and disc deformation were analyzed. Results showed that fixed charge density, fluid pressure, and water content decreased significantly in the nucleus pulposus (NP) and the inner to middle annulus fibrosus (AF) regions of the degenerative disc. It was found that, with degenerative progression, the Von Mises stress (relative to that at healthy state) increased within the disc, with a larger increase in the outer AF region. Both the disc volume and height decreased with the degenerative progression. The predicted results of fluid pressure change in the NP were consistent with experimental findings in the literature. The knowledge of the variations of temporal and spatial distributions of composition and mechanical signals within the human IVDs provide a better understanding of the progression of disc degeneration.  相似文献   
8.
This study aimed to investigate the Pb and Cd contamination and health risk assessment for population via consumption of vegetables sold in fresh markets around the lower north of Thailand. The concentrations of Pb and Cd in various vegetables such as root/tuber, stem, inflorescence, fruit, and leaf vegetables were analyzed using an atomic absorption spec-trophotometer. Human health risks of these metals in vegetables were assessed based on target hazard quotient (THQ). The results indicated that more than 80% of the Pb and Cd in almost all vegetable samples exceeded the maximum allowable concentration by National Food Institute criteria with an average range of 0.96–3.39 and 0.48–1.40 mg/kg, respectively. The estimated daily intakes (EDI) of Pb and Cd via dietary consumption of vegetables were between 0.001–0.010 and 0.002–0.008 mg/kg/d, respectively. All EDIs of Pb contaminated vegetables were higher than the reference dose recommended by the USEPA except for leaf edible vegetables, while all EDIs of Cd contaminated vegetables were higher than the reference dose recommended by the USEPA. THQ indicated that the consumption of Pb contaminated root/tuber, stem, inflorescence, and fruit edible vegetables and Cd contaminated leaf vegetable for the local population in the lower north of Thailand could be a severe health risk problem.  相似文献   
9.
A field experiment was carried out to determine whether group-foragingstarlings (Sturnus vulgaris) use public information to helpthem estimate the quality of an artificial resource patch anddepart accordingly. Three kinds of information are potentiallyavailable in a group: patch-sample information, pre-harvestinformation, and public information. These three types of informationcan be combined into four patch assessment strategies: (1) patch-samplealone; (2) patch-sample and pre-harvest; (3) patch-sample andpublic; and (4) patch-sample, pre-harvest, and public. Dependingon the foraging environment we presented to the starlings, eachassessment strategy made a unique set of predictions concerningthe patch departure decisions of pairs of birds based on differencesin their foraging success. The environment was manipulated intwo ways: by altering the variability in patch quality and bychanging compatibility, the ease with which individual birdscould simultaneously acquire both patch-sample and public information.Our observations on patch persistence and departure order demonstratethat the starlings used a combination of patch-sample and publicinformation, but not pre-harvest information, to estimate thequality of the experimental patch. Moreover, our results suggestthat starlings use public information only when it is easilyavailable and ignore it under incompatible conditions. Thisstudy provides the first evidence of public information usein a patch assessment problem.  相似文献   
10.
Sewage disposal in aquatic environments can have significant impacts on assemblages of organisms. There have been few field investigations on effects of sewage disposal on fish larvae. Data on abundances of larvae, current velocities and the size and shape of sewage plumes from point-source shoreline outfalls off Sydney (Australia) indicated that alongshore currents could transport large numbers of fish larvae into plumes, potentially affecting their health. Assemblages of fish larvae in surface sewage plumes differed to those in distant shelf (control) waters, but no such impacts were detected for assemblages in subsurface (20 m depth) waters beneath plumes. No predictable negative or positive numerical responses of fish larvae to sewage disposal were detected. Abundances of fish larvae fluctuated greatly in space and throughout time, and responses appeared to vary between taxa, outfalls and sampling periods. However, the large inherent level of natural spatial and temporal variability in abundances of larvae confounded the detection of possible impacts. Future field investigations need to focus on effects of sewage disposal on the health and condition of fish larvae. Designs for future field-based studies are discussed.  相似文献   
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