47 research outputs found
Remnants and Revenants: politics and violence in the work of Agamben and Derrida
No full textThis is the peer reviewed version of the following article: Frazer, Elizabeth, and Kimberly Hutchings. "Remnants and revenants: politics and violence in the work of Agamben and Derrida." The British Journal of Politics & International Relations 13.2 (2011): 127-144, which has been published in final form at http://dx.doi.org/10.1111/j.1467-856X.2010.00428.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Jacques Derrida and Giorgio Agamben both consider the question of whether there can be politics without violence, offering contrasting responses. In the case of Agamben, the remnant (that which remains) is disruptive and destabilising of present institutions; in the case of Derrida the revenant, the spectre, promises a future that is open. This reading of the two theories suggests that Derrida's response to the question of politics and violence is more persuasive than Agamben's. But the abstraction of his argument, like the tensions and contradictions in Agamben's, means that we are not hereby furnished with the resources to think politically about violence
Arginine depletion as a mechanism for the immune privilege of corneal allografts.
No full textThe cornea is an immune privileged tissue. Since arginase has been found to modulate T-cell function by depleting arginine, we investigated the expression of arginase in the cornea and its possible role in immune privilege using a murine transplant model. We found that both the endothelium and epithelium of murine corneas express functional arginase I, capable of down-regulating T-cell proliferation in an in vitro culture system. The administration of the specific arginase inhibitor N-hydroxy-nor-L-Arg to recipient mice resulted in an accelerated rejection of allogeneic C57BL/6 (B6) corneal grafts. In contrast, in vivo blockade of arginase activity had no effect in altering the course of rejection of primary skin grafts that express little, if any, arginase. In addition, the inhibition of arginase did not alter systemic T-cell proliferation. These data show that arginase is functional in the cornea and contributes to the immune privilege of the eye, and that modulation of arginase contributes to graft survival
Supporting safe motherhood : a review of financial trends : summary
No full textAn estimated 500,000 women, 99 percent of them from the developing world, die each year from pregnancy-related causes. About three quarters of these deaths are the direct result of obstetrical complications -- hemorrhage, infection, toxemia, obstructed labor, and abortion (under primitive and illegal conditions). An estimated equivalent number of infants do not survive their mother's death. For surviving mothers, the consequences of pregnancy have a severe impact on health and family economics. The strategy for safe motherhood is based on two approaches. First, the encouragement of activities that indirectly improve maternal health. These include education, policies to improve women's rights and working conditions, health care and nutrition, transportation and communication systems, water and sanitation facilities, and increases in family income and food production. The second approach targets activities to reduce maternal deaths. These activities include reducing unwanted pregnancies through the provision of family planning services, and through national policies that recognize the importance of this issue. A second objective is to reduce the risks of pregnancy through providing community-based family planning and prenatal services to identify high-risk cases'adequate referral services for the complications of pregnancy, and communication and transport systems to support patient referral procedures.Health Monitoring&Evaluation,Health Systems Development&Reform,Gender and Health,Early Child and Children's Health,Agricultural Knowledge&Information Systems
Lessons learned from a pan-European study of large housing estates : origin, trajectories of change and future prospects
No full textThe research leading to this work has received funding from the European Union’s Horizon 2020 research and innovation programme under Marie Skłodowska-Curie grant agreement number 655601. Support also came from three grants from the Estonian Research Council: Institutional Research Grant IUT2-17 on Spatial Population Mobility and Geographical Changes in Urban Regions, Infotechnological Mobility Observatory, and RITA-Ränne. The European Research Council funded this research under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC [Grant Agreement No. 615159] (ERC Consolidator Grant DEPRIVEDHOODS, Socio-spatial inequality, deprived neighbourhoods, and neighbourhood effects).Mid-twentieth-century large housing estates, which can be found all over Europe, were once seen as modernist urban and social utopias that would solve a variety of urban problems. Since their construction, many large housing estates have become poverty concentrating neighbourhoods, often with large shares of immigrants. In Northern and Western Europe, an overlap of ethnic, social and spatial disadvantages have formed as ethnic minorities, often living on low incomes, settle in the most affordable segments of the housing market. The aim of this introductory chapter is to synthesise empirical evidence about the changing fortunes of large housing estates in Europe. The evidence comes from 14 cities—Athens, Berlin, Birmingham, Brussels, Budapest, Bucharest, Helsinki, Madrid, Milan, Paris, Moscow, Prague, Stockholm and Tallinn—and is synthesised into 10 takeaway messages. Findings suggest that large housing estates are now seen as more attractive in Eastern Europe than in Western Europe. The chapter also provides a diverse set of visions and concrete intervention measures that may help to improve the fortunes of large housing estates and their residents
The Chebyshev center as an alternative to the analytic center in the feasibility pump
No full text© The Author(s) 2023As a heuristic for obtaining feasible points of mixed integer linear problems, the feasibility pump (FP) generates two sequences of points: one of feasible solutions for the relaxed linear problem; and another of integer points obtained by rounding the linear solutions. In a previous work, the present authors proposed a variant of FP, named analytic center FP, which obtains integer solutions by rounding points in the segment between the linear solution and the analytic center of the polyhedron of the relaxed problem. This work introduces a new FP variant that replaces the analytic center with the Chebyshev center. Two of the benefts of using the Chebyshev center are: (i) it requires the solution of a linear optimization problem (unlike the analytic center, which involves a convex nonlinear optimization problem for its exact solution); and (ii) it is invariant to redundant constraints (unlike the analytic center, which may not be well centered within the polyhedron for problems with highly rank-defcient matrices). The computational results obtained with a set of more than 200 MIPLIB2003 and MIPLIB2010 instances show that the Chebyshev center FP is competitive and can serve as an alternative to other FP variants.This research has been supported by the MCIN/AEI/FEDER project RTI2018-097580-B-I00.
Funding Open Access funding provided thanks to the CRUE-CSIC agreement with Springer NaturePeer ReviewedPostprint (published version
Supporting safe motherhood : a review of financial trends : full report
No full textThis study is designed to measure financial trends and new initiatives in support of the Safe Motherhood (SM) Initiative, identify issues of statistical methodology that may constrain the analysis, and establish a baseline for 1988 against which to measure future financial trends. Global support for specific safe motherhood activities is limited. Funding for selected safe motherhood activities is estimated to have increased (in current dollars) from 818.8 million in 1988. About half this amount was for so-called core activities, including family planning services. The magnitude of support for prevention of the complications of pregnancy is less certain. General health, population and nutrition sector flows increased substantially over the same period and estimated World Bank safe motherhood expenditures in 1989 are triple the previous year's total. New specific safe motherhood activities are beginning to emerge in the form of care for the complications of pregnancy, better secondary and tertiary facilities, training and promotional workshops. In conclusion, it is clear that policies to support maternal health are widely endorsed. However, the effectiveness of donor financing may require far greater attention to two special problems: (a) improving data on SM financial trends; and (b) strengthening recipient countries'capacity to activate project demand.Early Child and Children's Health,Agricultural Knowledge&Information Systems,Health Monitoring&Evaluation,Health Systems Development&Reform,Gender and Health
Author response: Analysis of SUMO1-conjugation at synapses
No full textSUMO1-conjugation of proteins at neuronal synapses is considered to be a major post-translational regulatory process in nerve cell and synapse function, but the published evidence for SUMO1-conjugation at synapses is contradictory. We employed multiple genetic mouse models for stringently controlled biochemical and immunostaining analyses of synaptic SUMO1-conjugation. By using a knock-in reporter mouse line expressing tagged SUMO1, we could not detect SUMO1-conjugation of seven previously proposed synaptic SUMO1-targets in the brain. Further, immunostaining of cultured neurons from wild-type and SUMO1 knock-out mice showed that anti-SUMO1 immunolabelling at synapses is non-specific. Our findings indicate that SUMO1-conjugation of synaptic proteins does not occur or is extremely rare and hence not detectable using current methodology. Based on our data, we discuss a set of experimental strategies and minimal consensus criteria for the validation of SUMOylation that can be applied to any SUMOylation substrate and SUMO isoform.</jats:p
Microscale light management and inherent optical properties of intact corals studied with optical coherence tomography
No full text© 2019 The Author(s) Published by the Royal Society. All rights reserved. Coral reefs are highly productive photosynthetic systems and coral optics studies suggest that such high efficiency is due to optimized light scattering by coral tissue and skeleton. Here, we characterize the inherent optical properties, i.e. the scattering coefficient, ms, and the anisotropy of scattering, g, of eight intact coral species using optical coherence tomography (OCT). Specifically, we describe light scattering by coral skeletons, coenoarc tissues, polyp tentacles and areas covered by fluorescent pigments (FP). Our results reveal that light scattering between coral species ranges from m s ¼ 3 mm 21 (Stylophora pistillata) to m s ¼ 25 mm 21 (Echinopora lamelosa). For Platygyra pini, m s was 10-fold higher for tissue versus skeleton, while in other corals (e.g. Hydnophora pilosa) no difference was found between tissue and skeletal scattering. Tissue scattering was threefold enhanced in coenosarc tissues (m s ¼ 24.6 mm 21 ) versus polyp tentacles (m s ¼ 8.3 mm 21 ) in Turbinaria reniformis. FP scattering was almost isotropic when FP were organized in granule chromatophores (g ¼ 0.34) but was forward directed when FP were distributed diffusely in the tissue (g ¼ 0.96). Our study provides detailed measurements of coral scattering and establishes a rapid approach for characterizing optical properties of photosynthetic soft tissues via OCT in vivo
60 gHz MAC and network design
No full textRecent technology advances are poised to enable low-cost, low-power communications in the 7 GHz of unlicensed spectrum at 60 GHz millimeter wave (mmW) frequencies. However, mmW systems that meet the Gb/s data rate demands of wireless multimedia applications must overcome severe propagation effects, including high path loss and high diffraction loss. Consequently, nodes in the network will have to use directional antennas. The narrow main beam widths of directional antennas introduce design challenges for Medium Access Control (MAC) protocols but, at the same time, provide opportunities for routing protocols to improve the network capacity through better spatial reuse. The small wavelength of a 60 GHz signal can help to achieve high directional antenna gain, but it also precludes diffraction around humans, furniture, and similarly-sized objects. These obstacles penalize a 60 GHz link budget by 20-30dB. Therefore, when people are in motion, 60 GHz network links go on and off frequently due to human body blockage; this introduces new design challenges for both routing and transport protocols. In this dissertation, we propose solutions at the MAC and network layer to address the above challenges. In particular, we first propose an enhanced directional MAC (EDMAC) to resolve the unfairness and low channel utilization issues of deafness in directional MAC protocols for 60 GHz networks. We then study single path routing and find that shortest path routing often fails to exploit the high spatial reuse properties of directional antennas. We propose two heuristic routing algorithms, namely HOP-FP and FP-HOP, which combine the fattest-path (FP) and minimum-hop (HOP) metrics, with and without the consideration of interference. We then employ multipath routing for 60 GHz networks to fully utilize the high spatial reuse property of directional antennas. We develop an online node-disjoint path discovery process to find multiple node-disjoint paths between the source and the destination without knowledge of the global topology. In addition, we model the characteristics of link outages that are induced by pedestrian blockage. Based on analytic models and MATLAB simulation results, we show that link blockages can be mitigated by multipath routing schemes with blockage timers for broken paths. We use the ns-2 simulator to validate all proposed protocols in this dissertation.Ph.D.Includes bibliographical referencesby Zhuo Che
Untersuchungen zur Aufbereitung abgelagerter Flotationsrückstände am Bergeteich Bollrich unter besonderer Berücksichtigung der Gewinnung wirtschaftsstrategischer Rohstoffe
No full textDie Dissertation thematisiert die mögliche Wiederaufbereitung abgelagerter Flotationsrückstände
des ehemaligen Erzbergwerks Rammelsberg am Bergeteich Bollrich in Goslar unter Berücksichtigung
der Gewinnung wirtschaftstragischer Rohstoffe. Hierfür werden im ersten Teil
der Arbeit mögliche Beweggründe für die Wiederaufbereitung von bergbaulichen Rückständen
zusammengefasst, auf das genannte Beispiel übertragen und Ziele für die Aufbereitungsentwicklung
abgeleitet. Aus der Sicht der Aufbereitung stellt das Bergeteichmaterial durch die
Feinheit des Materials (x50 < 10 μm), den Verwachsungsgrad sowie den geringen Wertstoffgehalt
eine schwierige Trennaufgabe dar. Das Bergeteichmaterial enthält zwar auf der einen Seite
einige potenziell wertvolle Metalle und Minerale, ebenso aber auch zahlreiche möglicherweise
schädlicher Komponenten. Die neu anfallenden Rückstände des Prozesses und der Schadstoffgehalt
sollten minimiert werden, um weiteren Flächenverbrauch, Deponierungskosten und mögliche
Umweltauswirkungen zu reduzieren und hierdurch Opportunitätserlöse zu erzielen.
Im zweiten Teil der Dissertation wird aufbauend auf der oben genannten Betrachtung ein möglicher
Aufbereitungsprozess experimentell entwickelt. Es konnte gezeigt werden, dass durch
eine gute Technik- und Parameterauswahl verschiedene Wertstoffe (v.a. Cu, Pb, Zn, Co und
BaSO4) aus dem Bergeteichmaterial gewonnen (ca. 70 %), ein Großteil der potentiellen Schadstoffe
entfernt (70 - 90 %) und die neu anfallenden Rückstände stark minimiert (50 %) werden
können. Die wesentlichen angewendeten Techniken sind Flotation, Laugung, Fällung und Lösemittelrückgewinnung.
Im entwickelten Prozess wird zunächst eine Mischsulfid-Flotation durchgeführt (Aerophine
3418 A, Flotanol C07 und Kupfersulfat) auf welche eine Baryt-Flotation (Lupromin FP E, Flotanol
C07 und Natronwasserglas) folgt. Aus dem Baryt-Konzentrat kann durch eine optimierte
Cleaner-Flotation, Zumischen von reinem Baryt (zur Einstellung der Körnung), einer thermischen
Behandlung und ggf. einer Blei-Laugung mit Citronensäure Bohrspat erzeugt werden.
Für das Sulfid-Konzentrat wurde eine Kombination aus Laugungen (Ammoniak mit Ammoniumcarbonat
sowie Citronensäure) entwickelt in deren Anschluss die Wertstoffe Kupfer, Zink
und Blei in Zwischenprodukte überführt werden können. Weiterhin kann der im Sulfid-Konzentrat
dominierende Pyrit (75 %) zur Schwefelsäureherstellung genutzt werden. Für die verbleibenden
Berge der Flotation sowie die eisenhaltigen Rückstände aus der hydrometallurgischen
Weiterverarbeitung des Sulfid-Konzentrats konnten mögliche Absteuerungs- und Verwertungswege
identifiziert werden, jedoch müssen diese im Weiteren untersucht werden.This Ph.D. thesis discusses the reprocessing of a tailing pond using the Bollrich tailing pond in
Goslar, Germany as an example.
In the first part, possible motives for the reprocessing of mining residues are described and
transferred to the case study. Furthermore, goals for the development of the reprocessing route
are derived. Regarding the reprocessing, the pond material poses a considerable challenge due
to its small grain size (x50 <10 μm), the degree of intergrowth and the low content of valuable
minerals. The tailings contain both potentially valuable metals and minerals as well as potentially
harmful elements. New process residues should be mitigated regarding overall mass and
the content of harmful substances in order to reduce further land use, landfill costs and possible
environmental impacts.
In the second part, the author describes a possible reprocessing route based on experimental
findings and the described goals. A skillful selection and combination of equipment and parameters
allows the extraction of valuable materials (especially Cu, Pb, Zn, Co and barite; approx.
70 %) from the tailings as well as the removal of the potential pollutants (70 - 90 %). In
addition, the process reduces residues considerably (50%). The applied techniques are mainly
flotation, leaching, precipitation and ion exchange.
The Author suggests a mixed sulfide flotation (Aerophine 3418 A, Flotanol C07 and copper
sulfate) followed by a barite flotation (Lupromin FP E, Flotanol C07 and sodium silicate). After
cleaner flotation, adjustment of the grain size, leaching of contaminants and thermal treatment,
the process yields a barite product for drilling. A combination of leaching processes
(ammonia with ammonium carbonate and citric acid) with subsequent recovery processes
transfers copper, zinc and lead into intermediate products. The authors also proved that the
production of sulfuric acid from the contained pyrite (75% of the sulfide concentrate) is feasible
