DNAReplication: a database of information and resources for the eukaryotic DNA replication community

DNAReplication (at http://www.dnareplication.net) has been set up as a freely available single resource to facilitate access to information on eukaryotic DNA replication. This database summarizes organism-sorted data on replication proteins in the categories of nomenclature, biochemical properties, motifs, interactions, modifications, structure, cell localization and expression, and general comments. Replication concepts are defined and a general model of the steps in DNA replication is presented. Links to relevant websites and homepages of replication labs are provided. The site also has an interactive section where links to recent replication papers are posted and readers are provided with the facility to post comments about each paper. The interactive and links pages are modified weekly and the whole site is updated annually

Arctic and Antarctic polar mesosphere summer echoes observed with oblique incidence HF radars: analysis using simultaneous MF and VHF radar data

Polar mesosphere summer echoes (PMSEs) have been well studied using vertical incidence VHF radars at northern high-latitudes. In this paper, two PMSE events detected with the oblique incidence SuperDARN HF radars at Hankasalmi, Finland (62.3° N) and Syowa Station, Antarctica (69.0° S), are analyzed, together with simultaneous VHF and medium-frequency (MF) radar data. Altitude resolutions of the HF radars in the mesosphere and the lower thermosphere are too poor to know exact PMSE altitudes. However, a comparison of Doppler velocity from the HF radar and neutral wind velocity from the MF radar shows that PMSEs at the HF band appeared at altitudes within 80-90km, which are consistent with those from previous vertical incidence HF-VHF radar results. The HF-VHF PMSE occurrences exhibit a semidiurnal behavior, as observed by other researchers. It is found that in one event, PMSEs occurred when westward semidiurnal winds with large amplitude at 85-88km altitudes attained a maximum. When the HF-VHF PMSEs were observed at distances beyond 180km from MF radar sites, the MF radars detected no appreciable signatures of echo enhancement. <br><br><b>Key words.</b> Meteorology and atmospheric dynamics (middle atmosphere dynamics; thermospheric dynamics; waves and tides

Statistical analysis of echo power, Doppler velocity and spectral width obtained with the Syowa South HF radar

Statistical analyses are made of the physical parameters (echo power, Doppler velocity and spectral width) of Doppler spectra obtained in September 1995 with the Syowa South HF radar. We present time and range distributions and histograms of the parameters and cross-correlations among them. With K index at Syowa Station the distributions and histograms vary slightly but the correlations do not change so much. The most noticeable feature is that there is a positive correlation between the absolute values of Doppler velocity and echo power. This relationship can be interpreted in terms of the gradient-drift instability which is the most probable cause to generate decameter-scale irregularities in the F-region ionosphere

Direct k-space mapping of the electronic structure in an oxide-oxide interface

The interface between LaAlO3 and SrTiO3 hosts a two-dimensional electron system of itinerant carriers, although both oxides are band insulators. Interface ferromagnetism coexisting with superconductivity has been found and attributed to local moments. Experimentally, it has been established that Ti 3d electrons are confined to the interface. Using soft x-ray angle-resolved resonant photoelectron spectroscopy we have directly mapped the interface states in k-space. Our data demonstrate a charge dichotomy. A mobile fraction contributes to Fermi surface sheets, whereas a localized portion at higher binding energies is tentatively attributed to electrons trapped by O-vacancies in the SrTiO3. While photovoltage effects in the polar LaAlO3 layers cannot be excluded, the apparent absence of surface-related Fermi surface sheets could also be fully reconciled in a recently proposed electronic reconstruction picture where the built-in potential in the LaAlO3 is compensated by surface O-vacancies serving also as charge reservoir.Comment: 8 pages, 6 figures, incl. Supplemental Informatio

A CROSS-SECTIONAL STUDY OF GENDER DIFFERENCES IN PULLING STRENGTH OF TOW FOR JAPANESE ELEMENTARY SCHOOL CHILDREN

The aim of this study was to obtain the data of gender differences of pulling strength during experimentally executed TOW for Japanese elementary school children. In mean back strength, gender difference was small from 1st grade to 4th grade, but on 5th and 6th grade, gender difference became large. In mean pulling strength, gender difference was large in 5th and 6th grade. But no tendency was found from 1st grade to 4th grade. In male children, sum of pulling strength increases substantially when the grade changes from 4th to 5th. But pulling strength tended to grow constantly. On the other hand, in female children, sum of pulling strength increases substantially when the grade changes from 2nd to 3rd. And from 4th to 6th, sum of back strength and rope tension were very close to each other. Results suggested that though male children get grow for muscles, female children get motor function more than male children

Modification of cell wall properties in lettuce improves shelf life

It is proposed that post-harvest longevity and appearance of salad crops is closely linked to pre-harvest leaf morphology (cell and leaf size) and biophysical structure (leaf strength). Transgenic lettuce plants (Lactuca sativa cv. Valeria) were produced in which the production of the cell wall-modifying enzyme xyloglucan endotransglucosylase/hydrolase (XTH) was down-regulated by antisense inhibition. Independently transformed lines were shown to have multiple members of the LsXTH gene family down-regulated in mature leaves of 6-week-old plants and during the course of shelf life. Consequently, xyloglucan endotransglucosylase (XET) enzyme activity and action were down-regulated in the cell walls of these leaves and it was established that leaf area and fresh weight were decreased while leaf strength was increased in the transgenic lines. Membrane permeability was reduced towards the end of shelf life in the transgenic lines relative to the controls and bacteria were evident inside the leaves of control plants only. Most importantly, an extended shelf-life of transgenic lines was observed relative to the non-transgenic control plants. These data illustrate the potential for engineering cell wall traits for improving quality and longevity of salad crops using either genetic modification directly, or by using markers associated with XTH genes to inform a commercial breeding programme