5,938 research outputs found
A Strategy for Partnering in the Public Sector
Partnering is a cooperative approach to contract management that reduces costs, litigation, and stress. The Portland District of the Corps of Engineers has successfully used partnering as a formal management strategy. This paper presents an overview of the partnering strategy
The generation of images of surface structures by laser-accelerated protons
Ion acceleration by lasers is one of the most important innovations in
laser-plasma research in recent years. A mechanism that has gained great
attention due to the remarkable properties of the accelerated beam is
laser acceleration of protons from the rear surface of solid targets. A
striking prediction is that these protons are capable of generating images
of micro-structures present on this surface. These images might be useful
to measure properties of the accelerated beam. In this article, we address
the physics of the generation of images of surface structures imprinted
into the target back surface with laser-accelerated protons
Efficient molecular cloning of environmental DNA from geothermal sediments
An efficient and simple method for constructing an environmental library using mechanically sheared DNA obtained
directly from geothermal sediments is presented. The method is based on blunt-end modification of DNA
fragments followed by 3' -adenylation using Vent DNA polymerase and Taq DNA polymerase, respectively. The
prepared DNA fragments are then ligated into a TA cloning vector and used in the transformation of Escherichia
coli. This method has been successfully applied to the cloning of ORFs derived from uncultivated prokaryotes
present in geothermal sediment
Spectral Control via Multi-Species Effects in PW-Class Laser-Ion Acceleration
Laser-ion acceleration with ultra-short pulse, PW-class lasers is dominated
by non-thermal, intra-pulse plasma dynamics. The presence of multiple ion
species or multiple charge states in targets leads to characteristic
modulations and even mono-energetic features, depending on the choice of target
material. As spectral signatures of generated ion beams are frequently used to
characterize underlying acceleration mechanisms, thermal, multi-fluid
descriptions require a revision for predictive capabilities and control in
next-generation particle beam sources. We present an analytical model with
explicit inter-species interactions, supported by extensive ab initio
simulations. This enables us to derive important ensemble properties from the
spectral distribution resulting from those multi-species effects for arbitrary
mixtures. We further propose a potential experimental implementation with a
novel cryogenic target, delivering jets with variable mixtures of hydrogen and
deuterium. Free from contaminants and without strong influence of hardly
controllable processes such as ionization dynamics, this would allow a
systematic realization of our predictions for the multi-species effect.Comment: 4 pages plus appendix, 11 figures, paper submitted to a journal of
the American Physical Societ
Rival bishops, rival cathedrals : the election of Cormac, archdeacon of Sodor, as bishop in 1331
Peer reviewedPublisher PD
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