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1.
Aino Juslén Juha Pykälä Saija Kuusela Lauri Kaila Jaakko Kullberg Jaakko Mattila Jyrki Muona Sanna Saari Pedro Cardoso 《Biodiversity and Conservation》2016,25(3):569-585
For the first time ever, the International Union for Conservation of Nature Red List Index for habitat types was calculated for an entire country, Finland. The RLIs were based on species threat assessments from 2000 and 2010 and included habitat definitions for all 10,131 species of 12 organism groups. The RLIs were bootstrapped to track statistically significant changes. The RLI changes of species grouped by habitats were negative for all habitat types except for forests and rural biotopes which showed a stable trend. Trends of beetles and true bugs were positive in rural and forest habitats. Other 16 observed trends of species group and habitat combinations were negative. Several trends observed were in accordance with studies focusing on particular taxa and habitats, and drivers for their change. This study demonstrates the usefulness of the RLI as a tool for observing habitat change based on species threat assessment data. 相似文献
2.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
3.
Transforming growth factor-beta (TGF-beta) induces a marked decrease in adhesion of MG-63 human osteosarcoma cells to laminin-coated surfaces, but does not significantly alter adhesion to fibronectin- or collagen-coated surfaces. We provide evidence that this effect is due to a switch in the repertoire of cell adhesion receptors in response to TGF-beta. MG-63 cells express high levels of alpha 3 beta 1-integrin, which is a polyspecific laminin/collagen/fibronectin receptor, and low levels of alpha 2 beta 1- and alpha 5 beta 1-integrins, which are collagen and fibronectin receptors, respectively. No other integrins of the beta 1-class could be detected in MG-63 cells. Treatment with TGF-beta 1 induces a marked (approximately 60%) decrease in the level of expression of alpha 3-integrin subunit mRNA and protein and a concomitant 8-fold increase in alpha 2-subunit expression. These responses become maximal 7-12 h after addition of TGF-beta 1 to the cells. Expression of alpha 5- and beta 1-integrin subunits also increases in response to TGF-beta 1, but to a lesser extent than alpha 2-subunit expression. Thus, as a result of TGF-beta action, the alpha 2 beta 1-collagen and alpha 5 beta 1-fibronectin receptors replace the alpha 3 beta 1-laminin/collagen/fibronectin receptor as the predominant integrins of the beta 1-class in MG-63 cells. These results suggest that one of the effects of TGF-beta is to modify the adhesive behavior of certain tumor cells by changing the binding specificity of the complement of integrins that they express. 相似文献
4.
P. Heino G. Sandman V. Lång K. Nordin E. T. Palva 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,79(6):801-806
Summary Abscisic acid (ABA) has been implicated as a regulatory factor in plant cold acclimation. In the present work, the cold-acclimation properties of an ABA-deficient mutant (aba) of Arabidopsis thaliana (L.) Heynh. were analyzed. The mutant had apparently lost its capability to cold acclimate: the freezing tolerance of the mutant was not increased by low temperature treatment but stayed at the level of the nonacclimated wild type. The mutational defect could be complemented by the addition of exogenous ABA to the growth medium, restoring freezing tolerance close to the wild-type level. This suggests that ABA might have a central regulatory function in the development of freezing tolerance in plants. Cold acclimation has been previously correlated to the induction of a specific set of proteins that have been suggested to have a role in freezing tolerance. However, these proteins were also induced in the aba mutant by low temperature treatment. 相似文献
5.
The effects of source and caging on the valve movements of the freshwater unionid mussel (Anodonta anatina) were studied in a reciprocal transplant experiment between a lake and its outflow. Caged mussels were moved and compared with those remaining in their natural environment on the lake or river bottom. At both sites, the mussels from the study site and the transplanted mussels from the opposite site were monitored simultaneously. In river the averaged weighted valve openness was higher and the number of valve movements was lower than in the lake. The mussels monitored in the lake exhibited a diurnal rhythm of valve movements which differed between the lake-bottom and the caged animals. Caging was found to increase valve openness. On the other hand, little variation appeared in valve openness between caged and bottom animals in the river, where diurnal rhythms were almost nonexistent. In the river the valve movements were more variable in respect to time than in the lake. 相似文献
6.
7.
M. Heino V. Kaitala E. Ranta J. Lindstr?m 《Proceedings. Biological sciences / The Royal Society》1997,264(1381):481-486
We explore extinction rates using a spatially arranged set of subpopulations obeying Ricker dynamics. The population system is subjected to dispersal of individuals among the subpopulations as well as to local and global disturbances. We observe a tight positive correlation between global extinction rate and the level of synchrony in dynamics among thesubpopulations. Global disturbances and to a lesser extent, migration, are capable of synchronizing the temporal dynamics of the subpopulations over a rather wide span of the population growth rate r. Local noise decreases synchrony, as does increasing distance among the subpopulations. Synchrony also levels off with increasing r: in the chaotic region, subpopulations almost invariably behave asynchronously. We conclude that it is asynchrony that reduces the probability of global extinctions, not chaos as such: chaos is a special case only. The relationship between global extinction rate, synchronous dynamics and population growth rate is robust to changes in dispersal rates and ranges. 相似文献
8.
A. Christine Engblom Michael J. Courtney Jyrki P. Kukkonen Karl E. O. Åkerman 《Journal of neurochemistry》1997,69(5):2162-2168
Abstract: The effect of ethanol on the intracellular Ca2+ concentration response to NMDA in rat cerebellar granule cells grown in low or high KCI concentrations has been studied using image analysis. The cells grown in low KCI displayed high sensitivity for glycine. The subtype-selective antagonist ifenprodil inhibited the response with high (in the low micromolar range) and low (in the high micromolar range) potency. Ethanol affected the high-potency component in these cultures. In cells grown in high KCI the glycine sensitivity was lower, and a low potency for ifenprodil (high micromolar) dominated. These cells were not significantly sensitive to ethanol. The results indicate that the component displaying potency for ifenprodil in the low micromolar range with properties of the NR2B subunit is the target for ethanol action on the NMDA receptor. 相似文献
9.
Smooth-pursuit eye movements were recorded in two rhesus monkeys in order to compare the influence of structured visual backgrounds
on smooth-pursuit initiation, steady-state pursuit and pursuit termination. Different target trajectories were used in order
to study smooth-pursuit initiation and termination. The influence of visual backgrounds on pursuit initiation was characterized
by recording ocular responses elicited by step-ramp target displacements starting from straight ahead. Pursuit termination
was characterized by analysing the transition from steady-state smooth-pursuit to fixation when a centripetally directed target
ramp was terminated by a small target step in the direction of the ramp as soon as the target had come close to the straightahead
position. The quantification of steady-state pursuit was based on ocular responses elicited by either paradigm. In accordance
with previous work, we found that the onset of smooth-pursuit eye movements was delayed and initial eye acceleration reduced
in the presence of a structured visual background. Likewise, mean eye velocity during steady-state pursuit was reduced by
structured visual backgrounds. However, neither the latency nor the time course of smooth-pursuit termination was altered
when the homogeneous background was replaced by a structured visual background. The lack of sensitivity of pursuit termination
to the presence of visual structured backgrounds supports a previous contention that pursuit termination is mediated by a
process which is different from the ones mediating smooth-pursuit initiation and steady-state pursuit. The absence of any
noticeable effect of structured backgrounds on pursuit termination suggests that at least the fast component of the optokinetic
reflex is suppressed during pursuit termination.
Received: 24 October 1994/Accepted in revised form: 16 December 1994 相似文献
10.
A rapid and efficient method to enrich SAF-protein from scrapie brains of hamsters 总被引:20,自引:0,他引:20
Scrapie hamster brains contain at least 5–10 g of scrapie-associated fibrils (SAF) per brain as estimated by the amount of its major constituent, a protein of about 26 000 daltons (SAF-protein). It can be extracted efficiently by a 10% solution of sarkosyl and can be enriched by differentia] centrifugation and buffer extraction. Scrapie infectivity, SAF, and SAF-protein copurify. 相似文献