950 research outputs found
The"IPO-Plus": a new approach to privatization
Every approach to privatization entails tradeoffs. The chief advantage of case-by-case privatization -including sales for cash or initial public offerings (IPOs)- is efficiency. Case-by-case privatization generates revenues, gives shareholders control over managers, and provides access to capital and skills. But it is slow and does not promote widespread public participation. Voucher-based mass privatization programs, by contrast, are designed to promote equity in the distribution of wealth, through widespread participation. But they do not ensure efficiency because they may not generate revenues, bring in new capital or skills, or give shareholders control over managers. To promote equity and efficiency, the authors propose a new form of privatization -IPO-Plus- that incorporates key features of both case-by-case privatization and mass privatization. IPO-Plus promotes equity through widespread (but not mass) participation in privatization. It promotes efficiency by making privatization transparent, by fostering capital market development, and by creating independent financial institutions that would press companies to improve their financial performance. It relies not on vouchers but on the sale of low-priced public shares. It allows deferred payment for company shares as an incentive to purchase them as well as downwardly flexible share prices. Because the quality of the enterprises chosen for privatization is essential to the success of the IPO-Plus program, it is important that few enterprises targeted for IPO-Plus be published before the program is launched. This will motivate potential investors to join the program by setting up management companies, establishing public investment funds, and buying shares in them. IPO-Plus is more likely than mass privatization to create real owners. Investors in IPO-Plus are given a subsidy, but only in proportion to what they themselves choose to pay. The individual determines (up to a ceiling) how much to invest in the program. IPO-Plus is particularly appropriate where the objective is to encourage outside ownership rather than significant employee ownership. It encourages the emergence of market intermediaries and ensures the concentration of enterprise shares in investment funds. Outside ownership and concentration of share voting rights provide the basis for enterprise restructuring and economic growth.Payment Systems&Infrastructure,International Terrorism&Counterterrorism,Economic Theory&Research,Banks&Banking Reform,Municipal Financial Management,Banks&Banking Reform,Municipal Financial Management,Payment Systems&Infrastructure,Economic Theory&Research,International Terrorism&Counterterrorism
Near-field coupling of gold plasmonic antennas for sub-100 nm magneto-thermal microscopy
The development of spintronic technology with increasingly dense, high-speed,
and complex devices will be accelerated by accessible microscopy techniques
capable of probing magnetic phenomena on picosecond time scales and at deeply
sub-micron length scales. A recently developed time-resolved magneto-thermal
microscope provides a path towards this goal if it is augmented with a
picosecond, nanoscale heat source. We theoretically study adiabatic
nanofocusing and near-field heat induction using conical gold plasmonic
antennas to generate sub-100 nm thermal gradients for time-resolved
magneto-thermal imaging. Finite element calculations of antenna-sample
interactions reveal focused electromagnetic loss profiles that are either
peaked directly under the antenna or are annular, depending on the sample's
conductivity, the antenna's apex radius, and the tip-sample separation. We find
that the thermal gradient is confined to 40 nm to 60 nm full width at half
maximum for realistic ranges of sample conductivity and apex radius. To
mitigate this variation, which is undesirable for microscopy, we investigate
the use of a platinum capping layer on top of the sample as a thermal
transduction layer to produce heat uniformly across different sample materials.
After determining the optimal capping layer thickness, we simulate the
evolution of the thermal gradient in the underlying sample layer, and find that
the temporal width is below 10 ps. These results lay a theoretical foundation
for nanoscale, time-resolved magneto-thermal imaging.Comment: 24 pages including Supporting Information, 6 figures in the main
text, 4 supporting figure
A classification of finite rank dimension groups by their representations in ordered real vector spaces
Peer reviewedPostprin
Existence of global solutions for a parabolic system related to the nonlinear Stokes problem
In this note we consider an initial-boundary value problem describing a nonlinear variant of the nonstationary Stokes equation. We prove the existence of a (unique) global solution with Galerkin-type arguments
Optical Dipole Structure and Orientation of GaN Defect Single-Photon Emitters
GaN has recently been shown to host bright, photostable, defect single photon
emitters in the 600-700 nm wavelength range that are promising for quantum
applications. The nature and origin of these defect emitters remain elusive. In
this work, we study the optical dipole structures and orientations of these
defect emitters using the defocused imaging technique. In this technique, the
far-field radiation pattern of an emitter in the Fourier plane is imaged to
obtain information about the structure of the optical dipole moment and its
orientation in 3D. Our experimental results, backed by numerical simulations,
show that these defect emitters in GaN exhibit a single dipole moment that is
oriented almost perpendicular to the wurtzite crystal c-axis. Data collected
from many different emitters shows that the angular orientation of the dipole
moment in the plane perpendicular to the c-axis exhibits a distribution that
shows peaks centered at the angles corresponding to the nearest Ga-N bonds and
also at the angles corresponding to the nearest Ga-Ga (or N-N) directions.
Moreover, the in-plane angular distribution shows little difference among
defect emitters with different emission wavelengths in the 600-700 nm range.
Our work sheds light on the nature and origin of these GaN defect emitters.Comment: 15 pages, 4 figure
T4 RNA Ligase 2 truncated active site mutants: improved tools for RNA analysis
<p>Abstract</p> <p>Background</p> <p>T4 RNA ligases 1 and 2 are useful tools for RNA analysis. Their use upstream of RNA analyses such as high-throughput RNA sequencing and microarrays has recently increased their importance. The truncated form of T4 RNA ligase 2, comprising amino acids 1-249 (T4 Rnl2tr), is an attractive tool for attachment of adapters or labels to RNA 3'-ends. Compared to T4 RNA ligase 1, T4 Rnl2tr has a decreased ability to ligate 5'-PO<sub>4 </sub>ends in single-stranded RNA ligations, and compared to the full-length T4 Rnl2, the T4 Rnl2tr has an increased activity for joining 5'-adenylated adapters to RNA 3'-ends. The combination of these properties allows adapter attachment to RNA 3'-ends with reduced circularization and concatemerization of substrate RNA.</p> <p>Results</p> <p>With the aim of further reducing unwanted side ligation products, we substituted active site residues, known to be important for adenylyltransferase steps of the ligation reaction, in the context of T4 Rnl2tr. We characterized the variant ligases for the formation of unwanted ligation side products and for activity in the strand-joining reaction.</p> <p>Conclusions</p> <p>Our data demonstrate that lysine 227 is a key residue facilitating adenylyl transfer from adenylated ligation donor substrates to the ligase. This reversal of the second step of the ligation reaction correlates with the formation of unwanted ligation products. Thus, T4 Rn2tr mutants containing the K227Q mutation are useful for reducing undesired ligation products. We furthermore report optimal conditions for the use of these improved T4 Rnl2tr variants.</p
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