bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory rainfall simulator studies of selected open-cut coal mine overburden spoils from Central Queensland
Authors: Evans K. G. , Loch R. J. , Aspinall T. O. , Bell L. C.
Published: August 2004

Data on the erodibility of overburden spoils resulting from open-cut coal
mining are limited. These data are required to derive parameters for erosion
prediction models which can be used in the design of re-formed landscapes
after mining.
In this study, laboratory rainfall simulation data were used to derive CREAMS
(Chemicals, Runoff and Erosion from Agricultural Management Systems) interrill
erodibility parameters K and
nbov for Central Queensland coal
mine overburden spoils. For the spoils studied, K values
ranged from 0·0111 to 0·1398
Mg·ha·h/(ha·MJ·mm) and
nbov values ranged from
0·0004 to 0·0081. Sediment yield was transport controlled.
Results for 1 spoil, South Blackwater Terang, showed that total soil loss
increased linearly with slope, and both K and
nbov varied non-linearly with
slope. If a constant set of K and
nbov values is used in modelling,
CREAMS over-predicts spoil loss for slopes greater than that for which the
parameter values were determined, and under-predicts spoil loss for slopes
less than that for which the parameter values were determined.
The results show evidence of differences between mine spoils and agricultural
soils, including modality of size distribution of surface sediment available
for erosion, a higher percentage of dispersed clays in eroded sediment from
mine spoils than from agricultural soils, and the observed amount of surface
sealing and crust formation. These differences indicate that
erosion{erodibility parameters for mine spoils should be measured and
that agricultural soil parameters should not be a basis for estimates of mine
spoil parameters.
Predicting the response of irrigated perennial pasture to superphosphate in Victoria
Authors: Gourley C. J. P. , James G. S.
Published: August 2004

Experiments were conducted at 42 sites in the northern and south-eastern
irrigation districts of Victoria to determine the relationship between
extractable phosphorus (P) using the Olsen P soil test, and response of
irrigated perennial pasture to an annual application of superphosphate.
Relative responses (the response relative to the maximum yield, P
non-limiting) were measured over 4 seasons (summer, autumn, winter, and
spring). At 12 of these sites, selected from a range of soils with different
clay contents, the effect of clay content on the curvature of the pasture dry
mass (DM) response was determined. Different soil-sampling methods, with the
surface organic mat included or excluded from the sample, were used to measure
Olsen P.
A well-defined linear model described the relationship between Olsen P values
of soil sampled using these two methods. There was no significant effect of
season on the relationship between relative response and Olsen P value. There
was also no significant relationship between the curvature of the response to
applied P and clay content of the soil. The derived relationship between Olsen
P soil test level and relative response to applied fertiliser accounted for
only 14 · 6% of the variation and it appears that other factors
are markedly affecting irrigated pasture response to applied superphosphate.
The accumulation of organic matter on the surface of irrigated perennial
pastures may be influencing nutrient availability and pasture growth, and
warrants further investigation.
Discrepancies between soil solute concentration estimates obtained by TDR and aqueous extracts
Authors: Nadler Arie
Published: August 2004

Soil moisture (θ) changes modify the electrical conductivity of the soil
solution (ECw) by varying the amount and composition of
dissolved ions, their activity coefficients, and soil tortuosity.
Theoretically expected, it was experimentally confirmed that the contribution
of common reactions (precipitation–dissolution,
adsorption–desorption, and complexation) to solute composition is not
always a linear function of soil : water ratios. Using the driest or wettest q
as references, correcting for dilution only when θ changed, did not fully
reconstruct the salinity. Bulk soil EC
(ECa)–ECw linkage, based on
the same mechanisms, is shown to have variable, curvilinear relations for
soils of medium salinity levels, which are enhanced by the presence of
sparingly soluble salts and clay content. An extreme disagreement between
ECw and ECc (EC of 1 : 1 soil :
water extracts adjusted for θ) was found for a clay soil, where up to ~2
dS/m the slope was negative.
Nitrogen cycling in brigalow clay soils under pasture and cropping
Authors: Robertson F. A. , Myers R. J. K. , Saffigna P. G.
Published: August 2004

Clay soils previously under native brigalow
(Acacia harpophylla) forest are highly productive under
annual cropping in central and southern Queensland. Grass pastures sown on
these soils are initially productive, but deteriorate after several years
because of N-stress (rundown). The aim of this work was to compare the
patterns of N cycling in these pasture and cropping systems, in order to
understand the rundown of the pastures. A small pulse of
15N-labelled ammonium sulfate was applied in the field
to sites cropped with sorghum (Sorghum bicolor) and
under green panic (Panicum maximum var.
trichoglume) pasture, and its movement through the soil
and plant pools was followed over 2 growing seasons.
There were large differences in the cycling of 15N in
the cropping and pasture systems. Under sorghum, 60% of the applied
15N was immobilised by microorganisms after 4 days,
after which it was re-mineralised. Plant uptake and stabilisation in soil
organic matter and clay were relatively slow. The first sorghum crop
assimilated 14% of the applied 15N. During the
second season, most of the 15N was stabilised in soil
organic matter and clay (maximum 42%). A significant proportion of the
15N remained in the soil inorganic pool over the 2
seasons.
Under green panic, 82% of the 15N left the soil
inorganic pool within 4 days and entered the microbial biomass, soil organic
matter, and the plant. Uptake and re-release of 15N were
most rapid in the microbial biomass (maximum uptake 34% of applied
after 4 days). Microbial immobilisation and re-mineralisation were, however,
slower under green panic than under sorghum. The pasture plant accumulated
32% of the applied 15N, two-thirds of which was
re-released in the second season. Stabilised N represented up to 62% of
the applied 15N, and was consistently greater under
green panic than under sorghum. After 2 seasons, 15N was
released from the stabilised N pool in both systems, at approximately the same
rate as it had been stabilised. At the end of the experiment, 40% of
the applied 15N was unaccounted for in the pasture
system, and 66% in the crop system.
The reduced N availability in the pasture system was attributed to
immobilisation of N in soil organic matter and clay, plant material, and, to a
lesser extent, soil microbial biomass. This immobilisation resulted from the
large accumulation of carbonaceous plant residues.
Change in infiltration characteristics associated with cultivation history of soils in south-eastern Queensland
Authors: Connolly R. D. , Freebairn D. M. , Bridge B. J.
Published: August 2004

Change in soil infiltration characteristics with cultivation can result in
reduced soil water storage, increased runoff and erosion, and reduced crop
production. We measured changes in infiltration characteristics associated
with years of cultivation for 5 soil groups in south-eastern Queensland. Soils
were grouped according to soil type and texture into Sodosols, light and heavy
Vertosols, Red Ferrosols, and Red Chromosols/Kandosols. Soil infiltration
characteristics were determined from measurements of permeability and
water-holding properties of the cultivated layer (0–0·1 m deep)
and the layer immediately below the plough layer (0·1–0·2
m deep). A rainfall simulator was used to measure the hydraulic conductivity
of surface seals and infiltration of bare, tilled soil in the field. Hydraulic
conductivity of the soil matrix and macropores and water-holding properties of
the 0·1–0·2 m layer were measured with disc permeameters
and pressure plate apparatus. Hydraulic conductivity of surface seals
decreased exponentially in all soil groups with period of cultivation; half of
the decline occurred within 2–6 years of first cultivation. Hydraulic
conductivity, macroporosity, and moisture characteristic of the
0·1–0·2 m layer were similarly affected by longer periods
of cultivation in all but light-textured soils. Cultivation of light-textured,
hardsetting soils (18% clay) did not adversely affect hydraulic
conductivity or macroporosity of the 0·1–0·2 m layer and
the loosening effect of tillage was somewhat beneficial for the water-holding
properties of this layer. The low hydraulic conductivities of the surface or
0·1–0·2 m layer after long periods of cultivation reduced
infiltration of rainfall in the field.
Effect of long-fallow on soil quality and cotton lint yield in an irrigated, self-mulching, grey Vertosol in the central-west of New South Wales
Authors: Hulugalle N. R. , Entwistle P. C. , Cooper J. L. , Allen S. J. , Nehl D. B.
Published: August 2004

Reduced crop growth rates (‘long-fallow disorder’) can be a
feature of long-fallow cotton (cotton, alternating with a bare fallow, is sown
every other year). This is usually attributed to decreased development of
arbuscular mycorrhiza (AM), although associated soil physical, chemical, and
biological properties are very rarely reported. A study was conducted from
1993 to 1997 in a grey, self-mulching Vertosol in the central-west of New
South Wales to characterise soil properties under long-fallow cotton with a
view to identifying soil factors other than AM that could contribute to cotton
growth rate reductions. Soil quality indicators monitored were compaction
(bulk density and air-filled porosity), strength (cone resistance), plastic
limit, exchangeable cations, nitrate-N, pH, organic C, development of AM, and
incidence of cotton root diseases. In comparison with continuous cotton,
long-fallow cotton had lower soil strength, and lower plastic limit.
Exchangeable Ca and Mg were higher with continuous cotton only in 1994. Higher
nitrate-N was also observed with long-fallow during the first fallow phase of
the experiment. Long-fallow did not have any significant effect on soil
organic carbon. However, a net decline in soil organic C and exchangeable Mg
occurred with both treatments. During the cotton phase, subsoil nitrate-N and
incidence of black root rot were lower with long-fallow cotton. Uptake of
nitrogen by continuous cotton may have been reduced by greater severity of
black root rot. Vegetative and reproductive growth, water extraction, and
cotton lint yields in long-fallow cotton plots were higher than those in
continuous cotton plots. AM development was similar with continuous cotton and
long-fallow cotton. Compared with long-fallow cotton, the lower lint yield in
continuous cotton was thought to be due to the interactive effects of
declining nutrient availability, higher soil strength, and greater severity of
black root rot causing decreases in nutrient and water uptake.
A Revision of Cullen (Leguminosae: Papilionoideae)
Authors: Grimes James W.
Published: August 2004

Cullen Medik. is a member of tribe Psoraleeae, all
members of which are characterised by delayed development of floral
vasculature, the presence of glands, and uniovulate ovaries.
Cullen is distinguished from the other members of the
tribe by discontinuous floral vasculature, and glandular, non-beaked fruits.
Field work and a morphometric analysis of the
Cullen patens-complex including 20 populations collected
throughout the eastern half of Australia, indicates that four species,
Cullen australasicum, C. discolor,
C. pallidum, and C. patens, may be
distinguished. A phylogenetic analysis indicates two main clades within
Cullen, one including species the stems of which are
branched at the base, and one in which the species are unbranched below.
Furthermore, this analysis shows Bituminaria to be
paraphyletic, Cullen includes 32 known species, 5 of
which, C. pogonocarpum,
C. leucochaites, C. praeruptorum,
C. candidum, and C. corallum are
described as new.
Factors affecting the trappability of red foxes in Kosciusko National Park
Authors: Bubela Tania , Bartell Robert , Müller Warren
Published: August 2004

The factors that affect the trappability of the red fox
(Vulpes vulpes L.) in alpine and subalpine New South
Wales were examined by means of treadle snares. Trapping (1) on animal tracks
without the use of a bait or lure, and (2) by setting snares around a bait,
led to the capture of individuals of both sexes and all age-classes. A greater
number of foxes was captured per number of snares set in winter than in other
seasons because of the commensal foraging patterns of foxes at this time.
Foxes were more likely to be caught within 100 m of their home-range
boundaries during snow-free months and outside their home ranges while
foraging at ski resorts in winter. Snares were found to be difficult to set,
and foxes were captured in only 50% of sprung snares. Treadle snares
caused no apparent long-term injuries to 40 red foxes that were radio- tracked
and observed for 1–24 months after capture.
Population indices for wild carnivores: a critical study in sand-dune habitat, south-western Queensland
Authors: Mahon Paul S. , Banks Peter B. , Dickman Chris R.
Published: August 2004

Populations of feral cats, foxes and dingoes were assessed at four sites in
the northern Simpson Desert from May 1995 to October 1996 using track counts.
Counts were based on presence/absence of footprints on sandplots placed
randomly throughout each of the four sites, with all habitats being sampled in
accordance with their availability. Sandplots were repositioned between
sampling periods so that data were temporally independent. This unbiased
method was used to assess the reliability of more conventional indices of
carnivore abundance based on spotlighting and counts of footprints on roads,
which were run concurrently with the random sandplot counts. The sandplot data
were also used to assess habitat use of the three study species.
Counts on regularly spaced sampling plots along roads were correlated with
random sandplot counts for foxes, but not for cats. Conversely, an index of
activity based on counting individual tracks along roads was correlated for
cats, but not for foxes. Spotlighting counts appeared to have little
relationship with random sandplot counts for either species, with random
sandplot counts and spotlight counts of foxes being correlated for only one of
the four sites and no correlations being apparent for cats.
The sandplot data showed that cats used dune crests preferentially over other
habitats, while foxes preferred both dune crests and roads. Dune crests are
probably used as natural runways by both species. Dingoes used roads
preferentially over other habitats. It was concluded that differences in the
use of roads and other runways by the carnivores can potentially lead to
biases in indices collected along roadways. In relation to the random sandplot
counts, foxes were overestimated by road counts and spotlighting relative to
cats, the latter bias being related possibly to temporal differences in the
activity patterns of the two species.
The importance of insects and lerp in the diet of juvenile regent honeyeaters, Xanthomyza phrygia: implications for the conservation of an endangered woodland bird
Authors: Oliver Damon L.
Published: August 2004

The dietary items fed to regent honeyeater,
Xanthomyza phrygia, nestlings and fledglings by adults
were recorded in two consecutive breeding seasons in the
Bundarra–Barraba region west of Armidale, New South Wales. Insects were
the most common dietary items fed to juveniles (53% of identified
items), followed by lerp (26.5%) and nectar (20.5%). Nestlings
were fed mostly insects (58% of feeds), and carbohydrates (nectar and
lerp) made up the rest of their diet. Fledglings, however, were fed mainly
carbohydrates (nectar and lerp comprised 61.2% of all items) while
protein from insects was the other major component of their diet. Males tended
to feed juveniles more insects than did females, although there were no
significant divisions of labour between parents in selecting dietary items for
nestlings or fledglings. This study highlights the importance of insects and
lerp in the diet of juvenile regent honeyeaters, and the diversity of plant
species on which their parents foraged. The species shows a broader resource
selection than was found in previous studies which considered the species to
be highly nectarivorous and selective for a few key eucalypt species. The
importance of insects and carbohydrates other than nectar in the diet of the
regent honeyeater needs to be recognised in the development of conservation
strategies for the species.
Home range and microhabitat use by the long-footed potoroo, Potorous longipes
Authors: Green K. , Mitchell A. T. , Tennant P.
Published: August 2004

Long-footed potoroos were studied at two widely-separated sites in Victoria,
one in regenerating eucalypt forest in East Gippsland and the other in
old-growth forest in Central Gippsland. Trap-revealed use of microhabitat at
Bellbird (East Gippsland) showed a change from the 1980s to 1990s, with an
increased amount of foraging in more open, drier areas. Over the same period,
there was an increase in the size of home range of animals and a near-doubling
of the minimum numbers of animals known to be alive on the trapping grid at
Bellbird. These changes occurred over a period when few environmental changes
occurred on the grid other than control of feral predators. Radio-tracking
data from 12 animals at the two sites showed a similar trend in use of
microhabitat by most animals, but there was individual variation. Differences
between the sites were that home-range size was smaller at the Riley trapping
grid (Central Gippsland), there was greater overlap in home range, and animals
there foraged for significantly shorter bouts. This confirmed earlier
speculation from reproductive and dietary studies that there is better quality
habitat at Riley, but the sites were so dissimilar that differences in home
range and foraging could not be ascribed to either the logging regime or to
geographical differences between the sites.
Diet and foraging behaviour of brush-tailed phascogales (Phascogale tapoatafa) in the jarrah forest of south-western Australia
Authors: Scarff F. R. , Rhind S. G. , Bradley J. S.
Published: August 2004

The diet and foraging behaviour of an arboreal marsupial, the brush-tailed
phascogale (Phascogale tapoatafa tapoatafa), was
examined in the jarrah forest of south-western Australia. Radio-tracking was
used to confirm the species’ nocturnal foraging habit and to make direct
observations of foraging behaviour. Eleven stomachs, and a collection of 45
scats obtained during summer and autumn, were microscopically examined for
content. The availability of major prey items (invertebrates found on or under
the bark of tree trunks) was quantified. Phascogales proved to be foraging
generalists, and their diet predominantly consisted of invertebrates. Some
invertebrate taxa appeared to be preferred but few taxa were avoided. Active
pursuit of vertebrates was negligible. However, the species appears
opportunistic, and scavenging of vertebrates may contribute to the diet.
Nectar was also taken, appearing to be a particularly prized but rare and
patchy food source. It is suggested that the current and former distributions
of this species have been constrained by both the seasonal reliability of
rainfall and the diversity of food resources.
Genome-wide molecular dissection of serotype M3 group A
Streptococcus
strains causing two epidemics of invasive infections
Authors: Beres Stephen B. , Sylva Gail L. , Sturdevant Daniel E. , Granville Chanel N. , Liu Mengyao , Ricklefs Stacy M. , Whitney Adeline R. , Parkins Larye D. , Hoe Nancy P. , Adams Gerald J. , Low Donald E. , DeLeo Frank R. , McGeer Allison , Musser James M.
Published: July 2004

Molecular factors that contribute to the emergence of new virulent bacterial subclones and epidemics are poorly understood. We hypothesized that analysis of a population-based strain sample of serotype M3 group A
Streptococcus
(GAS) recovered from patients with invasive infection by using genome-wide investigative methods would provide new insight into this fundamental infectious disease problem. Serotype M3 GAS strains (
n
= 255) cultured from patients in Ontario, Canada, over 11 years and representing two distinct infection peaks were studied. Genetic diversity was indexed by pulsed-field gel electrophoresis, DNA–DNA microarray, whole-genome PCR scanning, prophage genotyping, targeted gene sequencing, and single-nucleotide polymorphism genotyping. All variation in gene content was attributable to acquisition or loss of prophages, a molecular process that generated unique combinations of proven or putative virulence genes. Distinct serotype M3 genotypes experienced rapid population expansion and caused infections that differed significantly in character and severity. Molecular genetic analysis, combined with immunologic studies, implicated a 4-aa duplication in the extreme N terminus of M protein as a factor contributing to an epidemic wave of serotype M3 invasive infections. This finding has implications for GAS vaccine research. Genome-wide analysis of population-based strain samples cultured from clinically well defined patients is crucial for understanding the molecular events underlying bacterial epidemics.
An antiproliferative factor from interstitial cystitis patients is a frizzled 8 protein-related sialoglycopeptide
Authors: Keay Susan K. , Szekely Zoltan , Conrads Thomas P. , Veenstra Timothy D. , Barchi Joseph J. , Zhang Chen-Ou , Koch Kristopher R. , Michejda Christopher J.
Published: July 2004

Approximately 1 million people in the United States suffer from interstitial cystitis, a chronic painful urinary bladder disorder characterized by thinning or ulceration of the bladder epithelial lining; its etiology is unknown. We have identified a glycosylated frizzled-related peptide inhibitor of cell proliferation that is secreted specifically by bladder epithelial cells from patients with this disorder. This antiproliferative factor (APF) profoundly inhibits bladder cell proliferation by means of regulation of cell adhesion protein and growth factor production. The structure of APF was deduced by using ion trap mass spectrometry (MS), enzymatic digestion, lectin affinity chromatography, and total synthesis, and confirmed by coelution of native and synthetic APF derivatives on microcapillary reversed-phase liquid chromatography (μRPLC)/MS. APF was determined to be an acidic, heat-stable sialoglycopeptide whose peptide chain has 100% homology to the putative sixth transmembrane domain of frizzled 8. Both synthetic and native APF had identical biological activity in normal bladder epithelial cells and T24 bladder cancer cells. Northern blot analysis indicated binding of a probe containing the sequence for the frizzled 8 segment with mRNA extracted from cells of patients with interstitial cystitis but not controls. APF is therefore a frizzled-related peptide growth inhibitor shown to contain exclusively a transmembrane segment of a frizzled protein and is a potential biomarker for interstitial cystitis.
Time-resolved energy transfer in DNA sequence detection using water-soluble conjugated polymers: The role of electrostatic and hydrophobic interactions
Authors: Xu Qing-Hua , Gaylord Brent S. , Wang Shu , Bazan Guillermo C. , Moses Daniel , Heeger Alan J.
Published: July 2004

We have investigated the energy transfer processes in DNA sequence detection by using cationic conjugated polymers and peptide nucleic acid (PNA) probes with ultrafast pump-dump-emission spectroscopy. Pump-dump-emission spectroscopy provides femtosecond temporal resolution and high sensitivity and avoids interference from the solvent response. The energy transfer from donor (the conjugated polymer) to acceptor (a fluorescent molecule attached to a PNA terminus) has been time resolved. The results indicate that both electrostatic and hydrophobic interactions contribute to the formation of cationic conjugated polymers/PNA-C/DNA complexes. The two interactions result in two different binding conformations. This picture is supported by the average donor–acceptor separations as estimated from time-resolved and steady-state measurements. Electrostatic interactions dominate at low concentrations and in mixed solvents.
Insulin and Wnt1 Pathways Cooperate to Induce Reserve Cell Activation in Differentiation and Myotube Hypertrophy
Authors: Rochat Anne , Fernandez Anne , Vandromme Marie , Molès Jeàn-Pierre , Bouschet Triston , Carnac Gilles , Lamb Ned J. C.
Published: July 2004

During ex vivo myoblast differentiation, a pool of quiescent mononucleated myoblasts, reserve cells, arise alongside myotubes. Insulin/insulin-like growth factor (IGF) and PKB/Akt-dependent phosphorylation activates skeletal muscle differentiation and hypertrophy. We have investigated the role of glycogen synthase kinase 3 (GSK-3) inhibition by protein kinase B (PKB)/Akt and Wnt/β-catenin pathways in reserve cell activation during myoblast differentiation and myotube hypertrophy. Inhibition of GSK-3 by LiCl or SB216763, restored insulin-dependent differentiation of C2ind myoblasts in low serum, and cooperated with insulin in serum-free medium to induce MyoD and myogenin expression in C2ind myoblasts, quiescent C2 or primary human reserve cells. We show that LiCl treatment induced nuclear accumulation of β-catenin in C2 myoblasts, thus mimicking activation of canonical Wnt signaling. Similarly to the effect of GSK-3 inhibitors with insulin, coculturing C2 reserve cells with Wnt1-expressing fibroblasts enhanced insulin-stimulated induction of MyoD and myogenin in reserve cells. A similar cooperative effect of LiCl or Wnt1 with insulin was observed during late ex vivo differentiation and promoted increased size and fusion of myotubes. We show that this synergistic effect on myotube hypertrophy involved an increased fusion of reserve cells into preexisting myotubes. These data reveal insulin and Wnt/β-catenin pathways cooperate in muscle cell differentiation through activation and recruitment of satellite cell-like reserve myoblasts.
Insufficient Folding of Type IV Collagen and Formation of Abnormal Basement Membrane-like Structure in Embryoid Bodies Derived from Hsp47-Null Embryonic Stem Cells
Authors: Matsuoka Yasuhiro , Kubota Hiroshi , Adachi Eijiro , Nagai Naoko , Marutani Toshihiro , Hosokawa Nobuko , Nagata Kazuhiro
Published: July 2004

Hsp47 is a molecular chaperone that specifically recognizes procollagen in the endoplasmic reticulum. Hsp47-null mouse embryos produce immature type I collagen and form discontinuous basement membranes. We established Hsp47-/-embryonic stem cell lines and examined formation of basement membrane and production of type IV collagen in embryoid bodies, a model for postimplantation egg-cylinder stage embryos. The visceral endodermal cell layers surrounding Hsp47-/-embryoid bodies were often disorganized, a result that suggested abnormal function of the basement membrane under the visceral endoderm. Rate of type IV collagen secretion by Hsp47-/-cells was fourfold lower than that of Hsp47+/+cells. Furthermore, type IV collagen secreted from Hsp47-/-cells was much more sensitive to protease digestion than was type IV collagen secreted from Hsp47+/+cells, which suggested insufficient or incorrect triple helix formation in type IV collagen in the absence of Hsp47. These results indicate for the first time that Hsp47 is required for the molecular maturation of type IV collagen and suggest that misfolded type IV collagen causes abnormal morphology of embryoid bodies.
Visualization of Regulated Exocytosis with a Granule-Membrane Probe Using Total Internal Reflection Microscopy
Authors: Allersma Miriam W. , Wang Li , Axelrod Daniel , Holz Ronald W.
Published: July 2004

Secretory granules labeled with Vamp-green fluorescent protein (GFP) showed distinct signatures upon exocytosis when viewed by total internal reflection fluorescence microscopy. In ∼90% of fusion events, we observed a large increase in fluorescence intensity coupled with a transition from a small punctate appearance to a larger, spreading cloud with free diffusion of the Vamp-GFP into the plasma membrane. Quantitation suggests that these events reflect the progression of an initially fused and spherical granule flattening into the plane of the plasma membrane as the Vamp-GFP simultaneously diffuses through the fusion junction. Approximately 10% of the events showed a transition from puncta to ring-like structures coupled with little or no spreading. The ring-like images correspond quantitatively to granules fusing and retaining concavity (recess of ∼200 nm). A majority of fusion events involved granules that were present in the evanescent field for at least 12 s. However, ∼20% of the events involved granules that were present in the evanescent field for no more than 0.3 s, indicating that the interaction of the granule with the plasma membrane that leads to exocytosis can occur within that time. In addition, ∼10% of the exocytotic sites were much more likely to occur within a granule diameter of a previous event than can be accounted for by chance, suggestive of sequential (piggy-back) exocytosis that has been observed in other cells. Overall granule behavior before and during fusion is strikingly similar to exocytosis previously described in the constitutive secretory pathway.
Defective Epidermal Barrier in Neonatal Mice Lacking the C-Terminal Region of Connexin43
Authors: Maass Karen , Ghanem Alexander , Kim Jung-Sun , Saathoff Manuela , Urschel Stephanie , Kirfel Gregor , Grümmer Ruth , Kretz Markus , Lewalter Thorsten , Tiemann Klaus , Winterhager Elke , Herzog Volker , Willecke Klaus
Published: July 2004

More than 97% of mice in which the C-terminal region of connexin43 (Cx43) was removed (designated as Cx43K258stop) die shortly after birth due to a defect of the epidermal barrier. The abnormal expression of Cx43K258stop protein in the uppermost layers of the epidermis seems to perturb terminal differentiation of keratinocytes. In contrast to Cx43-deficient mice, neonatal Cx43K258stop hearts show no lethal obstruction of the right ventricular outflow tract, but signs of dilatation. Electrocardiographies of neonatal hearts reveal repolarization abnormalities in 20% of homozygous Cx43K258stop animals. The very rare adult Cx43K258stop mice show a compensation of the epidermal barrier defect but persisting impairment of cardiac function in echocardiography. Female Cx43K258stop mice are infertile due to impaired folliculogenesis. Our results indicate that the C-terminally truncated Cx43K258stop mice lack essential functions of Cx43, although the truncated Cx43 protein can form open gap junctional channels.
Protein–Protein Interactions Governing Septin Heteropentamer Assembly and Septin Filament Organization inSaccharomyces cerevisiae
Authors: Versele Matthias , Gullbrand Björn , Shulewitz Mark J. , Cid Victor J. , Bahmanyar Shirin , Chen Raymond E. , Barth Patrick , Alber Tom , Thorner Jeremy
Published: July 2004

Mitotic yeast (Saccharomyces cerevisiae) cells express five related septins (Cdc3, Cdc10, Cdc11, Cdc12, and Shs1) that form a cortical filamentous collar at the mother-bud neck necessary for normal morphogenesis and cytokinesis. All five possess an N-terminal GTPase domain and, except for Cdc10, a C-terminal extension (CTE) containing a predicted coiled coil. Here, we show that the CTEs of Cdc3 and Cdc12 are essential for their association and for the function of both septins in vivo. Cdc10 interacts with a Cdc3–Cdc12 complex independently of the CTE of either protein. In contrast to Cdc3 and Cdc12, the Cdc11 CTE, which recruits the nonessential septin Shs1, is dispensable for its function in vivo. In addition, Cdc11 forms a stoichiometric complex with Cdc12, independent of its CTE. Reconstitution of various multiseptin complexes and electron microscopic analysis reveal that Cdc3, Cdc11, and Cdc12 are all necessary and sufficient for septin filament formation, and presence of Cdc10 causes filament pairing. These data provide novel insights about the connectivity among the five individual septins in functional septin heteropentamers and the organization of septin filaments.
Surgical Resection of Calvarial Metastases Overlying Dural Sinuses
Authors: Michael Christopher B. , Gokaslan Ziya L. , DeMonte Franco , McCutcheon Ian E. , Sawaya Raymond , Lang Frederick F.
Published: July 2004

OBJECTIVE

Few reports have addressed the surgical management of cranial metastases that overlie or invade the dural venous sinuses. To examine the role of surgery in the treatment of dural sinus calvarial metastases, we reviewed retrospectively 13 patients who were treated with surgery at the University of Texas M.D. Anderson Cancer Center between 1993 and 1999. We compared them with 14 patients who had calvarial metastases that did not involve a venous sinus.

METHODS

Clinical charts, radiological studies, pathological findings, and operative reports were analyzed retrospectively.

RESULTS

The median age of patients with dural sinus calvarial metastases was 54 years. Nine patients were men and four were women. Renal cell carcinoma and sarcoma were the most common primary tumors. Similar features were noted in the 14 patients with nonsinus calvarial metastases. Of the 13 dural sinus calvarial metastases, 11 involved the superior sagittal sinus, and 2 involved the transverse sinus. In nine patients, the involved sinus was resected, and in four patients, the sinus was reconstituted after tumor removal. Nine patients in the dural sinus calvarial metastases group received en bloc resection, and four received piecemeal resection. No operative deaths occurred. The overall median actuarial survival was 16.5 months. The survival times of the two groups were comparable. In the group with dural sinus calvarial metastases, transient postoperative neurological deficits occurred in two patients (15%), and a permanent deficit occurred in one patient (8%). No patients in the group with nonsinus calvarial metastases experienced deficits after resection. Compared with piecemeal resection, en bloc resection was associated with significantly less blood loss.

CONCLUSION

Complete extirpation of calvarial metastases that overlie or invade a dural sinus can be achieved with only slightly more morbidity than complete removal of calvarial metastases that are located away from the sinuses. En bloc resection is as safe as piecemeal resection and is more effective in limiting operative blood loss. The overall recurrence and survival rates of patients with dural sinus calvarial metastases are similar to those of patients with calvarial metastases that do not involve the sinuses. Therefore, involvement of a dural venous sinus should not discourage resection of calvarial metastases. In carefully selected cancer patients, surgery provides effective palliation of symptomatic calvarial metastases that overlie or invade the venous sinuses.
Gender wage gaps and job mobility in Spain
Authors: Caparrós Ruiz Antonio , Lucía Navarro Gómez María , Federico Rueda Narváez Mario
Published: August 2004

Equal treatment for men and women is an important objective of labour policy in the European Union, largely because there is ample evidence of gender discrimination in the wages of men and women, which are on an average higher for male workers. Research on male‐female wage differentials provides evidence of a substantial wage differential favouring men after adjusting for human capital and personal characteristics such as education, age, job tenure, and labour force intermittency. However, few studies take into account the role that job mobility plays in this differential, despite its demonstrated importance in explaining the earnings profile of workers. This paper estimates gender wage differentials for workers who switch jobs and those who keep them in order to see whether job mobility enlarges or reduces the gender gap. The study uses microdata relative to Spanish workers gathered from the Households Panel Study (1994‐1997), conducted by the Spanish National Statistics Institute.
2D harmonic balance FE modelling of electromagnetic devices coupled to nonlinear circuits
Authors: Gyselinck J. , Dular P. , Geuzaine C. , Legros W.
Published: July 2004

This paper deals with the two‐dimensional finite element analysis in the frequency domain of saturated electromagnetic devices coupled to electrical circuits comprising nonlinear resistive and inductive components. The resulting system of nonlinear algebraic equations is solved straightforwardly by means of the Newton‐Raphson method. As an application example we consider a three‐phase transformer feeding a nonlinear RL load through a six‐pulse diode rectifier. The harmonic balance results are compared to those obtained with time‐stepping and the computational cost is briefly discussed.
A 3D multimodal FDTD algorithm for electromagnetic and acoustic propagation in curved waveguides and bent ducts of varying cross‐section
Authors: Kantartzis Nikolaos V. , Katsibas Theodoros K. , Antonopoulos Christos S. , Tsiboukis Theodoros D.
Published: July 2004

This paper presents a curvilinearly‐established finite‐difference time‐domain methodology for the enhanced 3D analysis of electromagnetic and acoustic propagation in generalised electromagnetic compatibility devices, junctions or bent ducts. Based on an exact multimodal decomposition and a higher‐order differencing topology, the new technique successfully treats complex systems of varying cross‐section and guarantees the consistent evaluation of their scattering parameters or resonance frequencies. To subdue the non‐separable modes at the structures' interfaces, a convergent grid approach is developed, while the tough case of abrupt excitations is also studied. Thus, the proposed algorithm attains significant accuracy and savings, as numerically verified by various practical problems.
The highly efficient three‐phase small induction motors with stator cores made from amorphous iron
Authors: Dems M. , Komęza K. , Wiak S. , Stec T.
Published: July 2004

Applies the field/circuit two‐dimensional method and improved circuit method to engineering designs of the induction motor with stator cores made of amorphous iron. Exploiting of these methods makes possible computation of many different specific parameters and working curves in steady states for the “high efficiency” three‐phase small induction motor. Compares the results of this calculation with the results obtained for the classical induction motor with identical geometric structure.
Magnetoelastic coupling and Rayleigh damping
Authors: Belahcen A.
Published: July 2004

This paper presents a magnetoelastic dynamic FE model. As first approach, the effect of magnetostriction and strong coupling is not considered. The effect of Rayleigh damping factors on the vibrational behaviour of the stator core of a synchronous generator is studied using the presented model. It shows that the static approach is not accurate enough and the difference between calculations with damped and undamped cases is too important to be ignored. However, the difference between damped cases with reasonable damping is not very important.
Modelling of temperature‐dependent effective impedance of non‐ferromagnetic massive conductor
Authors: Doležel Ivo , Musil Ladislav , Ulrych Bohuš
Published: July 2004

Impedance of long direct massive conductors carrying time‐variable currents is a complex function of time. Its evolution is affected not only by the skin effect but also by the temperature rise. This paper presents a numerical method that allows one to compute the resistance and internal inductance of a non‐ferromagnetic conductor of any cross‐section from values of the total Joule losses and magnetic energy within the conductor, and also illustrates the theoretical analysis based on the field approach on a typical example and discusses the results.
Field strength computation at edges in nonlinear magnetostatics
Authors: Groh Friedemann , Hafla Wolfgang , Buchau André , Rucker Wolfgang M.
Published: July 2004

Magnetostatic problems including iron components can be solved by a nonlinear indirect volume integral equation. Its unknowns are scalar field sources. They are evaluated iteratively. In doing so the integral representation of fields has to be calculated. At edges singularities occur. Following a method to calculate the field strength on charged surfaces a way out is presented.
Genetic algorithm coupled with FEM‐3D for metrological optimal design of combined current‐voltage instrument transformer
Authors: Cundeva Marija , Arsov Ljupco , Cvetkovski Goga
Published: July 2004

The combined current‐voltage instrument transformer (CCVIT) is a complex non‐linear electromagnetic system with increased voltage, current and phase displacement errors. Genetic algorithm (GA) coupled with finite element method (FEM‐3D) is applied for CCVIT optimal design. The optimal design objective function is the metrological parameters minimum. The magnetic field analysis made by FEM‐3D enables exact estimation of the four CCVIT windings leakage reactances. The initial CCVIT design is made according to analytical transformer theory. The FEM‐3D results are a basis for the further GA optimal design. Compares the initial and GA optimal output CCVIT parameters. The GA coupled with FEM‐3D derives metrologically positive design results, which leads to higher CCVIT accuracy class.
Inverse problem – determining unknown distribution of charge density using the dual reciprocity method
Authors: Ogrizek Dean , Trlep Mladen
Published: July 2004

Presents the use of the dual reciprocity method (DRM) for solving inverse problems described by Poisson's equation. DRM provides a technique for taking the domain integrals associated with the inhomogeneous term to the boundary. For that reason, the DRM is supposed to be ideal for solving inverse problems. Solving inverse problems, a linear system is produced which is usually predetermined and ill‐posed. To solve that kind of problem, implements the Tikhonov algorithm and compares it with the analytical solution. In the end, tests the whole algorithm on different problems with analytical solutions.
Development of optimizing method using quality engineering and multivariate analysis based on finite element method
Authors: Okada Yukihiro , Kawase Yoshihiro , Sano Shinya
Published: July 2004

Describes the method of optimization based on the finite element method. The quality engineering and the multivariable analysis are used as the optimization technique. In addition, this method is applied to a design of IPM motor to reduce the torque ripple.
An improved fast method for computing capacitance
Authors: Song L. , Konrad A.
Published: July 2004

In the design of chip carriers, appropriate analysis tools can shorten the overall production cycle and reduce costs. Among the functions to be performed by such computer‐aided engineering software tools are self and mutual capacitance calculations. Since the method of moments is slow when applied to large multi‐conductors systems, a fast approximate method, the average potential method (APM), can be employed for capacitance calculations. This paper describes the improved average potential method, which can further reduce the computational complexity and achieve more accuracy than the APM.
Magnetic stimulation of knee – mathematical model
Authors: Sawicki Bartosz , Starzyński Jacek , Wincenciak Stanisław , Krawczyk Andrzej , Trlep Mladen
Published: July 2004

Arthritis, the illness of the bones, is one of the diseases which especially attack the knee joint. Magnetic stimulation is a very promising treatment, although not very clear as to its physical background. Deals with the mathematical simulation of the therapeutical technique, i.e. the magnetic stimulation method. Considers the low‐frequency magnetic field. To consider eddy currents one uses the pair of potentials: electric vector potential T→ and magnetic scalar potential Ω . Since the problem is of low frequency and the electric conductivity of biological tissues is very small, consideration of electric vector potential only is quite satisfactory.
Determination of a dynamic radial active magnetic bearing model using the finite element method
Authors: Polajžer Boštjan , Štumberger Gorazd , Dolinar Drago , Hameyer Kay
Published: July 2004

The dynamic model of radial active magnetic bearings, which is based on the current and position dependent partial derivatives of flux linkages and radial force characteristics, is determined using the finite element method. In this way, magnetic nonlinearities and cross‐coupling effects are considered more completely than in similar dynamic models. The presented results show that magnetic nonlinearities and cross‐coupling effects can change the electromotive forces considerably. These disturbing effects have been determined and can be incorporated into the real‐time realization of nonlinear control in order to achieve cross‐coupling compensations.
1H and 31P Spectroscopic Imaging of Epilepsy: Spectroscopic and Histologic Correlations
Authors: Hetherington Hoby P. , Kim Jung H. , Pan Jullie W. , Spencer Dennis D.
Published: July 2004

Summary:  Although MRS measurements are useful in assessing the biochemical alterations underlying human epilepsy, to date their use has been limited primarily by three factors: (a) the lack of widespread methods and appropriate hardware for acquiring high‐resolution spectroscopic imaging data, (b) difficulties in spectral interpretation associated with metabolic heterogeneity, and (c) difficulties in biological interpretation due to a lack of correlative histologic studies. In this work, we (a) describe approaches to overcome these hurdles, and (b) discuss the biological interpretation of the spectroscopic findings in TLE.
fMRI: Applications in Epilepsy
Authors: Detre John A.
Published: July 2004

Summary:  Functional MRI (fMRI) methods use currently standard MRI scanning hardware to detect changes in regional blood flow and metabolism that accompany regional brain activation. Major applications of fMRI in epilepsy include the localization of task‐correlated language and memory function, and the localization of ictal and paroxysmal phenomena. Language lateralization by fMRI provides comparable results to intracarotid amobarbital testing, and memory lateralization by fMRI also shows promise. The recent development of methodologies to allow interpretable electroencephalographic data to be recorded during MRI scanning has opened up new opportunities for combining the spatial resolution of imaging with the temporal resolution of electrophysiology in seizure localization.
Ictal SPECT in Nonlesional Extratemporal Epilepsy
Authors: Cascino Gregory D. , Buchhalter Jeffrey R. , Mullan Brian P. , So Elson L.
Published: July 2004

Summary:  Purpose: Ictal single‐photon emission computed tomography (SPECT) may be a reliable indicator of the ictal onset zone in patients with intractable partial epilepsy who are being considered for epilepsy surgery. The rationale for the illustrated case report is to evaluate the use of an innovation in SPECT imaging in a patient with nonlesional extratemporal epilepsy.

Methods: We investigated the presurgical evaluation and operative outcome in a patient with intractable partial epilepsy. The ictal semiology indicated a “hypermotor” seizure with bipedal automatism. The electroclinical correlation and magnetic resonance imaging (MRI) did not suggest the appropriate localization of the epileptogenic zone. A subtraction periictal SPECT coregistered to MRI (SISCOM) was peformed.

Results: SISCOM revealed a region of localized hyperperfusion in the right supplementary sensorimotor area. Chronic intracranial EEG monitoring confirmed the relationship between the localized SISCOM alteration and the ictal onset zone. The patient was rendered seizure free after surgical treatment.

Conclusions: SISCOM may be used to identify potential candidates for surgical treatment of nonlesional extratemporal epilepsy. Periictal imaging may also alter the strategy for intracranial EEG recordings and focal cortical resection.