132 research outputs found
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It’s not the size, it’s the relationship: from ‘small states’ to asymmetry
Debate about the definition of “small state” has produced more fragmentation than consensus, even as the literature has demonstrated its subjects’ roles in joining international organizations propagating norms, executing creative diplomacy, influencing allies, avoiding and joining conflicts, and building peace. However, work on small states has struggled to identify commonalities in these states’ international relations, to cumulate knowledge, or to impact broader IR theory. This paper advocates a changed conceptual and definitional framework. Analysis of “small states” should pivot to examine the dynamics of the asymmetrical relationships in which these states are engaged. Instead of seeking an overall metric for size as the relevant variable—falling victim in a different way Dahl’s “lump-of-power fallacy,” we can recognize the multifaceted, variegated nature of power, whether in war or peacetime
Synthesis, crystal structure and spin-density-wave anomaly of the iron arsenide-fluoride SrFeAsF
The new quaternary iron arsenide-fluoride SrFeAsF with the tetragonal
ZrCuSiAs-type structure was synthesized and the crystal structure was
determined by X-ray powder diffraction (P4/nmm, a = 399.30(1), c = 895.46(1)
pm). SrFeAsF undergoes a structural and magnetic phase transition at 175 K,
accompanied by strong anomalies in the specific heat, electrical resistance and
magnetic susceptibility. In the course of this transition, the space group
symmetry changes from tetragonal (P4/nmm) to orthorhombic (Cmme). 57Fe
Moessbauer spectroscopy experiments show a single signal at room temperature at
an isomer shift of 0.30(1) mm/s and magnetic hyperfine-field splitting below
the phase transition temperature. Our results clearly show that SrFeAsF
exhibits a spin density wave (SDW) anomaly at 175 K very similar to LaFeAsO,
the parent compound of the iron arsenide-oxide superconductors and thus SrFeAsF
may serve as a further parent compound for oxygen-free iron arsenide
superconductors.Comment: 5 pages, 7 figure
Risk-Based Oversight of Experiments in the Environment
The new biology has come of age. Basic research in fields ranging from immunology to plant biology has been transformed so as to be almost unrecognizable to those whose biology education ended before 1970. The spillover into commercial development likewise has been remarkable. Hardly a week passes without news of some new advance in an area such as therapeutics, vaccines, or plants and animals for food, feed, or fiber. These uses of biotechnology in contained laboratories, pilot plants, greenhouses, and production facilities have engendered little controversy. The National Institutes of Health Guidelines for Research Involving Recombinant DNA have exempted from oversight more than 95% of laboratory experiments (1); this has allowed organisms of low risk to be handled under modest containment conditions that permit large numbers of living organisms to be present In the workplace and even to be released from the laboratory. (2). Despite extensive work in thousands of laboratories throughout the United States with millions of individual genetic clones, there has been no report of their causing a human illness nor any injury to the environment. A bleak spot in this picture is tests in the environment, often termed field trials, planned introductions, or deliberate releases. A number have been subjected to extreme regulatory scrutiny and lengthy delays solely because recombinant DNA techniques were employed in the manipulation of the organism. This has occurred even when the genetic change was completely characterized, benign, and the organism demonstrably innocuous. The ripple effects have been substantial. Investigators have shied away from areas of research that require field trials of recombinant organisms (3); companies have felt compelled to eschew the newest, most precise and powerful techniques in favor of cruder but less regulated ones (4); and investors have avoided companies whose recombinant DNA-derived products require field trials (5)
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