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Critical Distance (critical + distance)
Selected AbstractsDispersal of adult aquatic Chironomidae (Diptera) in agricultural landscapesFRESHWATER BIOLOGY, Issue 3 2000Yannick R. Delettre SUMMARY 1This study investigates the possible influence of terrestrial landscape structure on the spatial distribution of adult Chironomidae emerging from water bodies in three agricultural areas, each with hedgerow networks, in Brittany (France). 2Using spatially explicit data from 128 yellow pan traps set in pairs at the bottom of hedges throughout the three study areas, we show that landscape structure and heterogeneity must be considered at two different spatial scales. 3At a global scale, distance to water bodies was the main factor explaining the spatial distribution of adult chironomids: both species richness and abundance changed beyond a critical distance to the stream, resulting in different species assemblages of flying insects. 4At a local scale, the abundance of species and individuals at rest in hedges changed with the quality of the hedge (mainly determined by canopy width and cover of the different vegetation layers). 5The density of the hedgerow network, and landscape openness, both influenced the dispersal of chironomid species from water bodies. 6This study, which provides the first estimate of the dispersal capabilities of chironomids in particular landscapes, suggests that the terrestrial environment is an essential component of population dynamics and community structure in aquatic Chironomidae. [source] Serving God's Mission Together in Christ's Way: Reflections on the Way to Edinburgh 2010INTERNATIONAL REVIEW OF MISSION, Issue 1 2010Jacques Matthey This paper argues that missio Dei theology must continue to provide the basis for an ecumenical missiology, provided certain problems are revisited, in line with themes of the 2010 Edinburgh study process. Among them is the need for emphasizing the vertical dimension of a transformative spirituality, somehow neglected in earlier ecumenical theologies. Only this will prevent an over-estimation of humanity's capacities. Within a missio Dei theology the specific role of the church is to be reaffirmed: there is no way back behind integration, which remains a cornerstone of an ecumenical approach, provided it keeps a critical distance to dogmatic ecclesiologies that tend to hinder progress towards visible unity. The debate on gospel and culture has to be urgently taken up again, through a positive appreciation of syncretism and the related search for criteria in intercultural hermeneutics. This will lead to articulating pneumatological approaches to mission with Christologies. Indeed, the New Testament texts with the most universal horizon refer to Christ as Word or Wisdom and not to the Holy Spirit. The paper moves on to ask whether then the relevance of the biblical wisdom tradition should not feature more in missiology. It could provide fertile approaches to witness in a religiously plural and ecologically damaged world. Ecumenical mission should in future be shaped by wisdom as much as it has been by prophecy, and keep both traditions in creative tension. [source] On The Frontlines or Sidelines of Knowledge and Power?INTERNATIONAL STUDIES REVIEW, Issue 3 2006Feminist Practices of Responsible Scholarship This presidential address challenges IR scholars to reflect on their scholarly responsibility in what some have termed a new age of empire and in which critics of US foreign policy,academics and otherwise,are increasingly under attack. Using the metaphor of frontlines and sidelines, the question is raised as to whether we can or should engage directly in the policy world or remain at a critical distance from it. This essay focuses on some ways in which feminist scholarship is responding to these questions and challenges. Claiming that knowledge and practice cannot be separated, feminists argue that the foundations of modern knowledge, built during an earlier age of empire, are implicated, often unconsciously, in the ways in which scholars and policymakers construct and respond to global events today. The divisive gendered dimensions of the clash of civilizations and the gendered workings of the global economy and the way we analyze it are presented to illustrate this claim. The essay presents some feminist reformulations that could contribute to more inclusionary theory and practice. [source] Language and sexuality in Spanish and English dating chats1JOURNAL OF SOCIOLINGUISTICS, Issue 4 2006Marisol Del-Teso-Craviotto Three half-hour conversations each from five English and four Spanish dating chat rooms were analyzed following conversation analytic methodologies. Participants in the chats often engaged in playful and humorous erotic conversations, using a set of interactionally negotiated conventions about chatting that constitute a play frame, characterized linguistically by graphemic representations of laughter, appropriations, reproduction of a humorous pronunciation, and interactions through alter personae. Such playfulness enhances participants' pleasure while allowing them to maintain critical distance, and balances the constraints of public interaction with the pursuit of private erotic pleasures. This study contributes to our understanding of the social and discursive dimension of sexuality, going beyond issues of sexual identity and focusing on the conversational negotiation of eroticism and desire. [source] A New Reading of Werther as Goethe's Critique of RousseauORBIS LITERARUM, Issue 6 2001Astrida Orle Tantillo This article argues for a new ironic reading of Werther, a reading that highlights Goethe's early critique of Rousseau's political philosophy. The article first compares key passages in Werther to Rousseau's Discours sur l'Origine et les Fondements de l'Inégalitéparmi les hommes and Essai sur l'origine des langues to show how Goethe uses Rousseau's texts to create a critical distance between the reader and the sentimental narrative. The article then analyzes Goethe's farcical play, Der Triumph der Empfindsamkeit. While the play is generally read as a satiric criticism of the public's reaction to Werther, this article contends that the play is also a commentary on Rousseau's philosophy and Werther itself. [source] Activity patterns of abalone under experimental conditionsAQUACULTURE RESEARCH, Issue 3 2001K Nakamura Abstract Locomotion behaviour of the abalone, Nordotis discus (Reeve), N. gigantea (Gmelin) and Sulculus aquatilis (Reeve), was observed for 5- to 10-day periods during the early summer and autumn from 1997 to 1999. Before sunset, the animals were individually put beneath each shelter situated on the flat concrete floor of indoor and outdoor tanks. For tracing of the locomotion path, a luminous rod was fixed on the animal's shell. Except for non-appearance, the locomotion behaviour showed leaving or homing; these ratios against each total observation according to each species were 70.0% and 16.7% in N. discus, 47.1 and 23.5% in N. gigantea and 57.6 and 24.2% in S. aquatilis respectively. Irrespective of species, recurrences to the home were frequently recognized during the locomotion. For the homing behaviour, its critical distance was approximately 1 m from the home. Moonlight did not completely restrain the abalone appearance from the home, though the appearance frequency during the period around the full moon was lowered and in some cases the time of initial appearance was retarded. [source] A Cascade FRET-Mediated Ratiometric Sensor for Cu2+Ions Based on Dual Fluorescent Ligand-Coated Polymer NanoparticlesCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2009Michel Frigoli Dr. Abstract Core-shell type dual fluorescent nanoparticles (NPs) in the 16,nm diameter range with a selective ligand (cyclam) attached to the surface and two fluorophores,9,10-diphenyl-anthracene (donor, D) and pyrromethene PM,567 (acceptor, A),embedded within the polymer core were synthesized and their fluorescent and copper-sensing properties were studied and compared to single D -doped and A -doped NPs. The acceptor (A) and donor (D) dyes were chosen to allow two sequential Förster resonance energy transfer (FRET) processes from D to A and from the encapsulated dyes to copper complexes that form at the surface and act as quenchers. NPs with different D/A loads were readily obtained by two consecutive entrapments of the dyes. Dual NPs present tunable fluorescence emission that is dependent on the doping ratio. FRET from D to A results in sensitized emission from A upon excitation of D, with FRET efficiencies reaching 80,% at high acceptor loads. A 9-fold amplification of the signal of A is observed at high D -to- A ratios. Single- and dual-dye-doped NPs were used to detect the presence of cupric ions in water by using the quenching of fluorescence as a transduction signal. In accordance with the spectral overlaps and the values of the critical distance (R0) of D, and A,copper complex pairs, the acceptor is much more sensitive than the donor. In dual fluorescent NPs, the sensitized emission of A is efficiently attenuated whereas the remaining emission of D is much less affected, allowing the detection of copper in a ratiometric manner upon excitation at a single (D) wavelength. Dual-dye-doped NPs with the highest acceptor loads (23,A -per-NP) were found to be the most sensitive for the detection of copper over a wide range of concentrations (20,nM to 8.5,,M). Owing to its great convenience and modularity, the cascade FRET strategy based on dual fluorescent NPs holds great promise for the design of various sensing nanodevices. [source] Avulsion of ascending lumbar and iliolumbar veins in anterior spinal surgery: An anatomical studyCLINICAL ANATOMY, Issue 5 2007G. Sivakumar Abstract To expose the disc between the 4th and 5th lumbar vertebrae in anterior spinal surgery, left to right retraction of inferior vena cava and aorta is required. This manoeuvre can be complicated by venous haemorrhage that, in most cases, is due to avulsion of the left ascending lumbar vein (ALV) or the left iliolumbar vein (ILV). We dissected 23 embalmed cadavers to assess the factors that contribute to the risk of tearing these two veins during retraction. We describe a triangular region that should help surgeons in identifying the ALV and ILV. This triangle is defined by the lateral border of the common iliac vein, the medial border of the psoas major muscle, and the superior end-plate of the L5 vertebral body. We observed that 3 cm between the termination of the left ALV, or a common stem with the ILV, and the termination of the common iliac vein is the critical distance, less than which the risk of venous avulsion is highest. Although the sample considered is small, our study seems to suggest that male patients tend to have a higher risk of venous avulsion than female patients. Clin. Anat. 20:553,555, 2007. © 2007 Wiley-Liss, Inc. [source] Equilibrium states of magnetized toroid,central compact object systemsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2009Jun Otani ABSTRACT Equilibrium configurations of self-gravitating magnetized toroid,central compact object systems have been constructed in the framework of the Newtonian gravity. We have succeeded in including not only poloidal but also toroidal magnetic fields under the ideal magnetohydrodynamic approximation. We find two new and interesting results about the critical equilibrium states of such systems beyond which no equilibrium states are allowed to exist. First, there appear critical distances from the central compact objects to the inner surfaces of the magnetized toroids. Furthermore, these critical distances are much larger than the distances of the innermost stable circular orbits. It implies that even if these systems would be treated in the framework of general relativity, there would appear cusp structures of the effective total potential of the gravitational and magnetic forces for strongly magnetized toroids which are different from the general relativistic cusp structures. Secondly, since the strength of the magnetic field for the critical equilibrium configurations is roughly 1015 G if the mass of the central object is 1.4 M, and the maximum density of the toroid is 1011 g cm,3, the existence of equilibrium states of toroids around compact objects seems to set limit to the maximum value of the magnetic field of the system to be ,1015 G, i.e. no stronger magnetic fields can be realized for the systems consisting of magnetized toroids and central compact objects with the masses around the typical neutron star mass. The value of the maximum density of the toroid, 1011 g cm,3, is taken from the theoretical computational results of binary neutron star merging simulations in full general relativity. [source] Vegetative Characteristics of Recently Reforested Bottomlands in the Lower Cache River Watershed, Illinois, U.S.A.RESTORATION ECOLOGY, Issue 3 2003Brian S. Kruse Abstract Interest in restoring native ecosystems is resulting in conversion of marginal agricultural lands to bottomland hardwood-dominated forests in the midwestern and midsouthern United States. Growing stock for these efforts typically consists of planted oak (Quercus spp.) and volunteer vegetation. Reports of mixed reforestation success and the lack of post-establishment tree growth data prompted this evaluation of vegetation characteristics of 5- to 7-year-old operational restorations in the Lower Cache River Watershed in southernmost Illinois, U.S.A. Fraxinus pennsylvanica (green ash), Acer negundo (box-elder), and Liquidambar styraciflua (sweetgum) together comprised 77% of all tree stems observed. Full stocking of overstory tree species can be expected to produce a closed canopy stand within 160 m of a forested edge, due primarily to the abundance of rapidly growing volunteer-origin trees. Planted oaks contributed minimally to total tree stocking but were present in sufficient numbers to eventually improve wildlife habitat, and therefore satisfied restoration objectives. Oak height was 23% greater when in the presence of a non-oak tree species. Herbaceous cover was dominated by Solidago gigantea (late goldenrod) and Juncus spp. (rushes). Solidago gigantea was associated with poor growth and low density of non-oak stems, whereas Juncus dudleyi (Dudley's rush) was associated with taller non-oak stems. These results suggest that the presence of volunteer-origin trees is crucial for the creation of full stand stocking that will result in rapid development of a closed canopy forest. Improved success of future reforestation efforts will require more intensive methods to establish adequate stocking beyond 160 m of a forest edge. Methods described here could be adapted for agricultural field to forest restorations in other regions to predict critical distances from volunteer seed sources within which supplemental planting would be unnecessary to meet tree stocking objectives. [source] Deterministic and Probabilistic Estimation of Appropriate Distances: Motivation for Considering the Consequences for Industrial SitesCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 2 2009M. Gawlowski Abstract Accidents and disruptions in chemical process installations can, in principle, lead to the rare events in which the release of flammable and/or toxic substances occurs, and which at particular distances from the installation can result in a hazard potential due to thermal radiation, blast wave effects or the concentration of toxic substances. The possibilities and limits of deterministic and probabilistic estimation methods for appropriate distances from hazardous installations, based on the example of an ammonia release and a large surface fire, are shown. In this, it is demonstrated that the deterministic and probabilistic approaches are in no way conflicting or unnecessary, but rather that they are complementary. The use of a deterministic estimation method leads to a maximum set radius of effects which only take account of the damage impact. Depending on the selection of the appropriate and suitable consequence models, critical distances are calculated which are in some cases much larger than the current standardised distances, as is shown by the example of large-scale fires. The use of a probabilistic estimation method leads to a range of distances for which the individual risk can be given in addition. In principle, iso-contours joining points of same risk or areas of same risk may be defined through the use of such estimations. [source] | ||||||||||||||||