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Time-frequency characterization of femtosecond extreme ultraviolet pulses.

We present energy-resolved cross-correlation measurements of an extreme ultraviolet (XUV) pulse, generated as the fifth harmonic (15.5 eV) of an intense 80 fs laser pulse centered at 400 nm. Spectrally resolving the cross-correlation signal allows us to characterize the time-dependent frequency of the XUV pulse. We find that the fifth harmonic has a small negative chirp in excess of that predicted

Beyond conventional stroke guidelines - Setting priorities

Background and Purpose - Priorities in the care of stroke patients are often intuitive. An open and translucent priority-setting procedure would benefit patients, professionals, and decision-makers. Prioritization is an innovative part of the new Swedish national stroke guidelines. Methods - Working groups identified diagnostic procedures, interventions and therapies in stroke care, assessed each

Defective chromosome segregation and telomere dysfunction in aggressive Wilms' tumors

Purpose: In many childhood neoplasms, prognostic subgroups have been defined based on specific chromosome changes. In Wilms' tumor (WT), such subclassification has been hampered by the diverse and relatively unspecific pattern of chromosomal imbalances present in these tumors. Unspecific patterns of cytogenetic imbalances in tumors are often caused by mitotic segregation errors due to short dysfun

Implicit associations and social anxiety

The aim of this study was to test whether an Implicit Association Test (IAT) with self- and social anxiety-words is sensitive to differences in trait social anxiety, and to an experimental induction of social anxiety. This was performed in the context of a partial replication of a previous study, in which Mauss et al. (2004) compared high and low trait socially anxious individuals before and after

Effects of liming on ectomycorrhizal fungi infecting Pinus-sylvestris L. 3. Saprophytic growth and host plant infection at different ph values in unsterile humus

Five ectomycorrhizal fungi were studied in relation to the effects of applications of lime and wood ash to the growth substrate. Growth and survival of inoculated fungi in unsterile humus and relative root colonization frequency by inoculated and indigenous ectomycorrhizal fungi were measured. Growth of the fungi was tested in Petri dish systems with humus taken from a field site treated with lime

Testing for anthropogenic influence on fire regime for a 600-year period in the Jaksha area, Komi Republic, East European Russia

In an attempt to quantitatively evaluate the natural versus anthropogenic signal in site fire histories, the statistical relationship between dendrochronologically dated fire events and tree-ring chronologies (deemed to be an independent proxy for climate variation) was analyzed for 14 sites in a 2600-km(2) area of pine-dominated forests in the Komi Republic (East European Russia) over the period

Health education to prevent anemia among women of reproductive age in southern India

In this study, we used a narrow, but easily measured, indicator of how communication proceeded among health workers and women in Southern India. Anemia prevention during pregnancy was studied using a semistructured questionnaire. Participants included 5 nurses, 10 health aides, and 10 (traditional birth attendants) TBAs working with maternal health care and education, as well as 32 women seeking m

Cytochrome b(6)f: structure for signalling and vectorial metabolism

Following decades of detailed kinetic and spectroscopic evidence, two new, independent X-ray structures for the cytochrome b(6)f complex of photosynthesis now reveal the arrangement of its key electron carriers relative to each other, and to their protein ligands. But these are not predictable additions to the structural collection. The complex is dimeric, and encloses a central chamber in which p

Growth and reactivity of titanium oxide ultrathin films on Ni(110)

Soft X-ray photoelectron spectroscopy (SXPS) and X-ray absorption near-edge structure (XANES) have been combined with low-energy electron diffraction (LEED) to examine the growth of titanium dioxide thin films on Ni(110). Depending on the initial titanium coverage, the formation of two different films is observed, a quasi-hexagonal phase and a film with rutile (110) rods. Spectroscopy (SXPS and XA

Symbolic technologies: Machines and the Marxian notion of fetishism

By extending the Marxian theory of fetishism from money and commodities to machines, we may achieve an epistemological shift in our understanding of the foundations of 'technological development'. The first part of the article discusses previous definitions of fetishism in order to distil some central themes that appear to be particularly significant to the argument on machine fetishism. It is arg

Influence of recirculation flow rate on the performance of anaerobic packed-bed bioreactors treating potato-waste leachate

The performance of anaerobic, packed-bed bioreactors treating leachate from potato waste was evaluated in terms of organic loading rate (OLR) as well as the recirculation flow rate. Two 1 litre bioreactors, filled with porous glass beads as biofilm carriers and with continuous recirculation flow rates of 10 ml min(-1) and 20 ml min(-1) respectively, were used in the experiment. The OLR applied to

Electrostatic contributions to residue-specific protonation equilibria and proton binding capacitance for a small protein

Charge-charge interactions in proteins are important in a host of biological processes. Here we use C-13 NMR chemical shift data for individual aspartate and glutamate side chain carboxylate groups to accurately detect site-specific protonation equilibria in a variant of the B1 domain of protein G (PGB1-QDD). Carbon chemical shifts are dominated by changes in the electron distribution within the s

Amplified fragment length polymorphism analysis identifies hybrids between two subspecies of warblers.

In the western Pyrenees (Southwest France and Northwest Spain), a narrow hybrid zone exists between the common chiffchaff Phylloscopus (collybita) collybita and the Iberian chiffchaff Phylloscopus (c.) brehmii. In this zone, which is approximately 20 km wide, mixed matings and individuals singing the songs of both taxa occur at substantial frequencies (24 and 8.6%, respectively), suggesting freque

Paperboard packages exposed to static loads–finite element modelling and ­experiments

The aim of this study was to analyse the mechanical behaviour of paperboard packages subjected to static compressive loads. The study was divided in three parts and experiments and finite element analysis conducted for each part. First, a panel of paperboard was subjected to edge compressive loading as a means of checking the material model. Second, the package was cut into segments and each segme