697 research outputs found
Book Reviews
Wesleyan Perspectives on the New Creation
M. Douglas Meeks, ed.
Nashville: Kingswood,
2004, 200 pp., paper, 2004, 25.00
Reviewed by Elaine A. Heath
The Evangelical Moment: The Promise of an American Religion
By Kenneth J. Collins
Grand Rapids: Baker Academic Press
2005, 288 pp., paper, 22.99
Reviewed by Nathan Crawford
Theology as History and Hermeneutics: A Post-Critical Evangelical Conversation with Contemporary Theology
Laurence W. Wood
Lexington: Emeth Publisher
2004, 261 pp.
Reviewed by Nathan Crawford
Resistance and Theological Ethics
Ronald H. Stone and Robert L. Stivers, eds.
Lanham, Maryland: Roman & Littlefield Publishers
2004, ri, 334 pp. paper, 28.95
Reviewed by Joerg Rieger
The Ripple Church: Multiply Your Ministry by Parenting New Churches
Phil Stevenson
Indianapolis, IN: Wesleyan Publishing House
2004. pp. 186, 35.00
Reviewed by John N. Oswalt
God is Not Religious, Nice, One of Us, an American, a Capitalist
D. Brent Laytham, ed.
Grand Rapids, Michigan: Press.
2004, 152 pp., paper, 19.95
Reviewed by Charles M. Woo
Late syn- to post-collisional magmatism in Madagascar: the genesis of the Ambalavao and Maevarano Suites
The East African Orogen involves a collage of Proterozoic microcontinents and arc terranes that became wedged between older cratonic blocks during the assembly of Gondwana. The Ediacaran–Cambrian Ambalavao and Maevarano Suites in Madagascar were emplaced during the waning orogenic stages and consist of weakly deformed to undeformed plutonic rocks and dykes of mainly porphyritic granite but also gabbro, diorite and charnockite. U-Pb geochronological data date emplacement of the Ambalavao Suite to between ca. 580 Ma and 540 Ma and the Maevarano Suite to between ca. 537 Ma and 522 Ma. Major and trace element concentrations are consistent with emplacement in a syn- to post-collisional tectonic setting as A-type (anorogenic) suites. Oxygen (δ¹⁸O of 5.27‰–7.45‰) and hafnium (εHf(t) of –27.8 to –12.3) isotopic data from plutons in the Itremo and Antananarivo Domains are consistent with incorporation of an ancient crustal source. More primitive δ¹⁸O (5.27‰–5.32‰) and εHf(t) (+0.0 to +0.2) isotopic values recorded in samples collected from the Ikalamavony Domain demonstrate the isotopic variation of basement sources present in the Malagasy crust. The Hf isotopic composition of Malagasy zircon are unlike more juvenile Ediacaran–Cambrian zircon sources elsewhere in the East African Orogen and, as such, Madagascar represents a distinct and identifiable detrital zircon source region in Phanerozoic sedimentary provenance studies. Taken together, these data indicate that high-T crustal anatexis, crustal assimilation and interaction of crustal material with mantle-derived melts were the processes operating during magma emplacement. This magmatism was coeval with polyphase deformation throughout Madagascar during the amalgamation of Gondwana and magmatism is interpreted to reflect lithospheric delamination of an extensive orogenic plateau.Donnelly B. Archibald, Alan S. Collins, John D. Foden, Justin L. Payne, Peter Holden, Théodore Razakamanan
High power diode-pumped Nd<sup>3+</sup> fibre laser
In the medical field high power fibre-coupled AlGaAs diode lasers operating around 800nm are already making an impact in surgery but for more specialised applications high powers at other wavelengths are required. It is an attractive idea to develop active fibres as add-ons to such fibre coupled diode systems increasing the range of applications of such devices at little extra cost and minimal additional complexity. Rare-earth-doped optical fibres exhibit the traditional advantages of a glass laser host of broad emission and absorption spectra but without the usual associated thermal problems. With fibre lasers wavelength selection and temperature stabilisation of the pump diode is unnecessary, and the emission spectra allows for broad tuning. Double-clad fibres comprising a doped core, usually single-moded located within a large multimode waveguide enable efficient pumping of fibre lasers with diode ways or diode bars. Fibre lasers can thus be considered as simple wavelength convertors and brightness enhancers for the high power but poorly specified output of diode sources. In the this paper we describe a multiwatt Nd3+ fibre laser pumped via a second cladding by the DIOMED 25 laser diode unit. This multi diode array source is designed for coupling up to 25 Watts of diode power into a plastic-clad silica fibre of 400µm diameter. The laser fibre which is a double-clad structure fabricated from lead-silicate glasses is interchangeable with the normal PCS delivery fibre. The device operates at 1.058µm with a slope efficiency >50% and a 150 times brightness enhancement. This laser though useful in itself is also a key intermediate laser for generation of high powers at other wavelengths. Tandem pumping of Tm3+ and Er3+/Yb3+ fibre lasers at 1.058µm enables efficient generation of 2.0µm and 1.55µm radiation respectively. In addition the Nd3+ laser can be operated close to 1.3µm and there are prospects for in-fibre frequency doubling of the 1.06µm line to generate a high power source in the green
Cladding pumped erbium fibre amplifier generating femtosecond pulses with an average power of 0.26W
Femtosecond pulse amplification in a cladding pumped fiber amplifier is demonstrated for the first time. A cladding-pumped Er3+ doped fiber amplifier generates 380fsec near-bandwidth-limited pulses at repetition rates up to 50MHz with an average power up to 0.26.
Diode-pumped high-average power femtosecond fiber laser systems
The recent progress in femtosecond laser technology is currently driven by the prospect of fully diode pumped systems, which promise the eventual replacement of the well-established Ti:sapphire laser in the field of ultrafast optics. Apart from more traditional diode-pumped solid-state lasers, fiber-based systems have received an increasing amount of attention due to the uniquely compact assemblies possible with fiber lasers. However, to date fiber lasers have replaced Ti:sapphire-based systems only in areas, were low power levels are required, such as the injection seeding of regenerative amplifiers. Here, we show that fiber lasers can also produce power levels and pulse widths that are sufficient for the pumping of optical parametric oscillators (OPOs) and amplifiers (OPAs)
Targeting the Ataxia Telangiectasia Mutated-null Phenotype in Chronic Lymphocytic Leukemia with Pro-oxidants
Inactivation of the Ataxia Telangiectasia Mutated gene in chronic lymphocytic leukemia results in resistance to p53-dependent apoptosis and inferior responses to treatment with DNA damaging agents. Hence, p53-independent strategies are required to target Ataxia
Telangiectasia Mutated-deficient chronic lymphocytic leukemia. As Ataxia Telangiectasia Mutated has been implicated in redox homeostasis, we investigated the effect of the Ataxia Telangiectasia Mutated-null chronic lymphocytic leukemia genotype on cellular responses to
oxidative stress with a view to therapeutic targeting. We found that in comparison to Ataxia Telangiectasia Mutated-wild type chronic lymphocytic leukemia, pro-oxidant treatment of Ataxia Telangiectasia Mutated-null cells led to reduced binding of NF-E2 p45-related factor-2 to antioxidant response elements and thus decreased expression of target genes. Furthermore, Ataxia Telangiectasia Mutated-null chronic lymphocytic leukemia cells contained lower levels of antioxidants and elevated mitochondrial reactive oxygen species. Consequently, Ataxia Telangiectasia Mutated-null chronic lymphocytic leukemia, but not tumours with 11q deletion or TP53 mutations, exhibited differentially increased sensitivity to pro-oxidants both in vitro and in vivo. We found that cell death was mediated by a p53- and caspase-independent mechanism associated with apoptosis inducing factor activity. Together, these data suggest that defective redox-homeostasis represents an attractive therapeutic target for Ataxia Telangiectasia Mutated-null chronic lymphocytic leukemia
Magnetic Field Generation in Stars
Enormous progress has been made on observing stellar magnetism in stars from
the main sequence through to compact objects. Recent data have thrown into
sharper relief the vexed question of the origin of stellar magnetic fields,
which remains one of the main unanswered questions in astrophysics. In this
chapter we review recent work in this area of research. In particular, we look
at the fossil field hypothesis which links magnetism in compact stars to
magnetism in main sequence and pre-main sequence stars and we consider why its
feasibility has now been questioned particularly in the context of highly
magnetic white dwarfs. We also review the fossil versus dynamo debate in the
context of neutron stars and the roles played by key physical processes such as
buoyancy, helicity, and superfluid turbulence,in the generation and stability
of neutron star fields.
Independent information on the internal magnetic field of neutron stars will
come from future gravitational wave detections. Thus we maybe at the dawn of a
new era of exciting discoveries in compact star magnetism driven by the opening
of a new, non-electromagnetic observational window.
We also review recent advances in the theory and computation of
magnetohydrodynamic turbulence as it applies to stellar magnetism and dynamo
theory. These advances offer insight into the action of stellar dynamos as well
as processes whichcontrol the diffusive magnetic flux transport in stars.Comment: 41 pages, 7 figures. Invited review chapter on on magnetic field
generation in stars to appear in Space Science Reviews, Springe
Gender Differences in Faculty Experience with Start-up Packages: A Case Study from a Public University in the Southeastern U.S.
Start-up packages are a tool for successful transition to an academic career. This institutional case study examined the faculty experience with start-up packages at one public university in the Southeastern United States including gender differences, content, negotiation, and perceived outcomes. A mixed method research design was utilized to answer the study research questions. Data were gathered through an online survey with quantitative and qualitative questions. Data from 121 participants were analyzed using descriptive statistics, chi‐squared test, and thematic analysis. Most start-up package agreements included moving expenses, personal computer and software, and start-up funds. On the other hand, child daycare, guaranteed junior sabbatical, and salary advancement were the most missing benefits in the agreements. Male faculty were able to obtain, significantly more often than female faculty, a specific number of years for secure funding, laboratory space, and student or postdoc funding in their agreements. Faculty were not well prepared for the negotiation process, and they were not aware what exactly they needed to establish a successful research program. Universities should focus more on the influence of start-up packages on faculty careers because perceived unfair treatment during the negotiation process or during administration can influence faculty performance and their turnover intentions
Production and Decay of D_1(2420)^0 and D_2^*(2460)^0
We have investigated and final states and
observed the two established charmed mesons, the with mass
MeV/c and width MeV/c and
the with mass MeV/c and width
MeV/c. Properties of these final states, including
their decay angular distributions and spin-parity assignments, have been
studied. We identify these two mesons as the doublet predicted
by HQET. We also obtain constraints on {\footnotesize } as a function of the cosine of the relative phase of the two
amplitudes in the decay.Comment: 15 pages in REVTEX format. hardcopies with figures can be obtained by
sending mail to: [email protected]
- …