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Laser ablation of graphite in different buffer gases
The KrF-laser ablation of graphite into 300 Torr of He, Ne, Ar, and Xe has been studied by fast imaging of the plasma emission and post-deposition analyses of collected film deposits. In each case, the soot which was redeposited on the irradiated rod following ablation was highly fullerene-deficient compared to the material collected on the sample disk 1.5 cm from the rod, as determined by laser desorption Fourier Transform Mass Spectrometry (FTMS) Investigation of the plasma plume propagation using fast ICCD photography reveals three main phases to the expansion: (1) forward motion, deceleration and stopping of the leading edge of the plume, (2) an apparent reflected shock within the plume which propagates backward and reflects from the rod surface, (3) coalescence of these two components, resulting in continued expansion and dissipation of the plasma and the appearance of glowing ultrafine particles. For the laser plume propagating in 300 Torr of Xe the characteristic time intervals for these three phases are 0-300 ns, 300-1000 ns, and 1-1000 {mu}s for phases (1), (2), and (3) respectively. The possible explanation of the observed difference in fullerene content is discussed on the basis of different plasma phases resulting in soot deposition on the rod and sample disk. The measurement of ro-vibrational spectra of electronically excited C{sub 2} has been performed. Rotational and vibrational temperatures, T{sub R} = 3000 {+-} 300K and T{sub V} = 6000 {+-} 500K have been obtained from the comparison of measured and calculated C{sub 2} -Swan band emission
Sex and the Single Gametophyte: Revising the Homosporous Vascular Plant Life Cycle in Light of Contemporary Research
Homosporous vascular plants are typically depicted as extreme inbreeders, with bisexual gametophytes that produce strictly homozygous sporophytes. This view is promulgated in textbook life cycles despite ample evidence that natural populations of most species regularly outcross. We review research on a variety of mechanisms, including genetic load, asynchronous production of eggs and sperm, and pheromonal control of gamete production, that actively promote heterozygosity in ferns and lycophytes. Evolution of the land plants cannot be reconstructed without accurate depictions of the unique life cycle that has helped make ferns the second most diverse lineage of vascular plants on Earth. With revised illustrations and definitions, we provide scientists, educators, and students with a contemporary understanding of fern and lycophyte reproduction, revealing them as evolutionarily dynamic and exploiting a wide range of mating systems
Cross-Border Acquisitions and Corporate Taxes: Efficiency and Tax Revenues
We find that reduced foreign corporate taxes may lead to inefficient foreign acquisitions if complementarities between foreign and domestic assets are low, and to efficient foreign acquisitions if such complementarities are high. Moreover, with large complementarities, foreign acquisitions can increase domestic tax revenues. The reason is that in the bidding competition between the foreign firms, all benefits from the acquisition, including tax advantages and evaded taxes, are competed away and captured by the domestic seller which, in turn, pays capital gains tax on the proceeds. Technical issues in the tax code, such as the treatment of goodwill deductibility, is also shown to crucially affect the pattern of foreign acquisitions
Fullerene triplet state production and decay: R2PI probes of CGO and in a supersonic beam
Lifetimes of the lowest triplet state of the two most stable fullerenes, Csa and &a, were measured in a supersonic beam by twocolor resonant two-photon ionization. When prepared by intersystem crossing from the singlet manifold, excited at 4.03 eV, these triplet states were found to have lifetimes of 42 and 41 us, respectively. The energies of these triplet states (1.7 and 1.6 eV, respectively) were measured by photoelectron spectroscopy of the corresponding negative ions
Outsourcing Governance: States and the Politics of a ‘Global Value Chain World’
Politics, and by extension states, are marginal in debates about the genesis, evolution
and functioning of the GVC-based global economy. We contend here that the core complexity of
state agency and state power needs to be much more carefully understood in GVC and related
debates, as a basis on which the governance of the evolving GVC world can be properly
theorised as revolving around the inseparability of economic and political power. We advance a
framework for understanding the role of politics and states in the construction and maintenance
of a GVC world, using a three-fold typology of facilitative, regulatory and distributive forms of
governance, and propose a notion of ‘outsourcing governance’ as an attempt to capture the
ways in which states purposefully, through active political agency, have engaged in a process of
delegating a variety of governance functions and authority to private actors. Our overarching
argument is normative: ‘outsourced governance’ of the form we currently observe is associated
with regressive distributional outcomes, and is antithetical to an inclusive and sustainable global
economy
Restriction fragment length polymorphisms distinguish among accessions of Ceratopteris thalictroides and C. richardii ( Parkeriaceae )
We have used cDNA clones as probes on Southern blots to detect restriction fragment length polymorphisms among seven Ceratopteris thalictroides accessions, three C. richardii accessions, and one putative interspecific hybrid. We found that the stringency of post-hybridization washes was a critical parameter affecting the quality of our blots; even with homologous cDNA sequences low stringency conditions resulted in a smear of signal, but high stringency washes gave blots with distinct bands. Most probes showed hybridization with four or more genomic fragments. Similarities in the number and size of fragments between and within species indicated that (i) C. richardii shows limited polymorphism among accessions tested, (ii) C. thalictroides is highly polymorphic, and (iii) Hawaiian accessions of C. thalictroides are divergent relative to their continental cohorts and among themselves. The putative interspecific hybrid did not group closely with either of these species.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41637/1/606_2004_Article_BF00939725.pd
National Government Responses to Marine Stewardship Council (MSC) Fisheries Certification: Insights from Atlantic Canada
Over the last decade, the proliferation of social and environmental certification programmes has attracted the attention of a growing number of political scientists interested in new forms of ‘private’ transnational governance. However, we still lack analyses on the nature and extent of different state responses to and involvement in new private transnational governance arrangements in particular sectors and in different jurisdictions. This paper advances our understanding of the interactions between nation-state and private transnational modes of governance by analysing the role of national government authorities in Marine Stewardship Council (MSC) fisheries certification in Atlantic Canada, known more for the disastrous collapse of Northern cod stocks than good marine stewardship. Focusing on the 2008 certification of Northern shrimp (Pandalus borealis) fisheries off the Province of Newfoundland and Labrador, the analysis finds that the implementation and maintenance of MSC certification in this case depended on significant support from government authorities. The delicate legitimacy of both authorities face a period of uncertainty in this case since some certified shrimp stocks appear to be in decline and perhaps also migrating northward off Newfoundland and Labrador
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