bluuebunny/crossref_metadata_2025 huggingface dataset:
Cosmogenic radionuclide evidence for the limited extent of last glacial maximum glaciers in the Tanggula Shan of the Central Tibetan Plateau
Authors: Colgan Patrick M. , Munroe Jeffrey S. , Shangzhe Zhou
Published: October 2005

Cosmogenic radionuclide (CRN) exposure ages provide evidence for the limited extent of last glacial maximum glaciers in the Tanggula Shan, central Tibetan Plateau. The most extensive advances occurred during or before marine oxygen isotope stage 6 (MIS-6) based on previous CRN exposure ages. The second most extensive advance occurred during or before MIS-4 based on previous ages and new ages of 41,400 ± 4300, and 66,800 ± 7100 10Be yr. A MIS-2 advance of less than 3 km occurred between 31,900 ± 3400 and 16,000 ± 1700 10Be yr.
Growth, population density and population structure of Cetraria nivalis during 240 years of primary colonization
Authors: HESTMARK Geir , SKOGESAL Olav , SKULLERUD Øystein
Published: October 2005

The growth of the alpine lichen Cetraria nivalis was followed in a chronosequence of 240 years of primary colonization in a glacier foreland in the Jotunheimen mountain range and National Park in Norway. The largest thallus of C. nivalis was 96 mm in diameter. It was found in the area that had been exposed for a maximum of 240 years. If this individual thallus became established at about the time the habitat was exposed, its average annual diameter increase has been 0·4 mm per year. The growth curve of C. nivalis does however exhibit a pattern of fast growth in the first years followed by a decrease in growth rate. In contrast the population density of C. nivalis increases through time in a linear manner, from 0·4 thalli/m2 in the areas recently exposed to 10·5 thalli/m2 in the sites exposed for maximum of 240 years. This suggests a fairly stable flow of propagules over the landscape through the years. The size distribution (population structure) of thalli within the foreland is skewed, with many small individuals and few big ones.
Do different logging strategies influence the abundance of epiphytic chlorolichens?
Authors: HILMO Olga , HYTTEBORN Håkan , HOLIEN Håkon
Published: October 2005

The effects of two logging strategies and edge effects on cover and abundance of the epiphytic chlorolichens Cavernularia hultenii, Platismatia glauca and P. norvegica were studied in an experimentally logged boreal spruce forest. Whether lichen size distribution within the three species was affected by logging regimes was also tested. One hundred and ten branches were sampled at random within: (1) fine-grained clearcuts consisting of 23 cutblocks 0·25 ha each; (2) coarse-grained clearcuts consisting of 3 clearcuts 2·25 ha each; and (3) a control area.

Of the three species studied, C. hultenii was the most vulnerable to logging, with an abundance much lower in logged areas than in the control area. By contrast, P. glauca was equally abundant in the fine-grained area and in the control area, but significantly less abundant in the coarse-grained area where it seems to have been adversely affected by a pronounced edge effect. No such edge effect, however, was noted in the fine-grained area. Juvenile thalli of C. hultenii and P. glauca were less frequent in the coarse-grained area than in the fine-grained and control areas, suggesting that the juvenile stage might be more sensitive to logging than mature thalli. These results indicate that creation of large clearcuts (2·25 ha) may not be in accordance with the goal of maintaining population size in either C. hultenii or P. glauca. However, P. glauca does not seem to be negatively influenced by a fine-grained logging pattern. No effect of logging strategy or distance from the forest edge was observed on P. norvegica. It follows from the above that any management plans aimed at maintaining population size should be based on an understanding of ecology and life history gleaned from the area in question.
Lambinonia, a new genus for Melanconium strigulae, a lichenicolous hyphomycete on foliicolous species of Strigula
Authors: SÉRUSIAUX Emmanuël , DIEDERICH Paul
Published: October 2005

The new genus Lambinonia Sérus. & Diederich is introduced for the lichenicolous hyphomycete Melanconium strigulae Elenkin & Woron. This species forms dark sporodochia on the surface or at the margin of the thalli, or extruding out of the perithecia and pycnidia of the foliicolous Strigula buxi, S. nemathora and S. nitidula. It is so far known from the western Caucasus (Georgia and Russia), southern Italy, Tenerife (Canary Islands), St-Lucia (West Indies), and Burundi and Rwanda in Africa. The new combination Lambinonia strigulae (Elenkin & Woron.) Sérus. & Diederich is introduced and a neotype collection is designated.
A new species in Melanohalea (Parmeliaceae, Ascomycotina) and new lichen records from India
Authors: DIVAKAR Pradeep K. , UPRETI Dalip K.
Published: October 2005

Melanohalea nilgirica Divakar & Upreti is described as new to science. Melanelixia glabroides (Essl.) O. Blanco et al., Melanohalea poeltii (Essl.) O. Blanco et al., M. septentrionalis (Lynge) O. Blanco et al., Parmelia isidioclada Vain., P. masonii Essl. & Poelt, Parmelinopsis afrorevoluta (Krog & Swinscow) Elix & Hale and Parmeliopsis ambigua (Wulfen) Nyl., are new records for the Indian lichen flora.
Schaereria dolodes (Nyl. ex Hasse) Schmull & T. Sprib.: a second corticolous species in the genus
Authors: SCHMULL Michaela , SPRIBILLE Toby
Published: October 2005

Schaereria dolodes (Nyl. ex Hasse) Schmull & T. Sprib. comb. nov., an epiphytic lichen species known from western North America was originally described as a member of the genus Lecidea sensu lato. However, its morphology is very characteristic of the genus Schaereria Körb. Here, we lectotypify the species and propose its placement in the latter genus. It is also reported as new to Canada from British Columbia.
A second Micarea with a hypothecial K+ violet pigment
Authors: CZARNOTA Paweł , COPPINS Brian J.
Published: October 2005

Micarea hypoviolascens sp. nov. (Pilocarpaceae) is described from an ancient woodland in western Scotland. It is the second species within Micarea known to have the olivaceous, K+ deep violet pigment (Sedifolia-grey) in the hypothecium.
Influence of habitat history on the distribution of Usnea longissima in boreal Scandinavia: a methodological case study
Authors: JOSEFSSON T. , HELLBERG E. , ÖSTLUND L.
Published: October 2005

Changes in habitat affect the distribution of species at different spatial and temporal scales. Our aim was to assess the use of several retrospective methods when determining habitat history and its influence on species distribution, using the pendent lichen Usnea longissima Ach. as a model organism. The study was carried out in a Norway spruce dominated forest, located in the middle boreal zone of northern Sweden. Historical sources (including forest inventories and maps) and dendrochronology were combined with field surveys to determine past stand characteristics with a high spatial precision. Also, present stand characteristics were thoroughly surveyed and the relationship between distribution of U. longissima and past and present habitat characteristics were evaluated. Our results showed that, despite the fact that historical logging was unevenly distributed within the study area, similarities in stand structure exist today. Several essential factors affecting the distribution of U. longissima could be related to changes in past stand structure, especially the extent and intensity of previous logging operations and the subsequent stand development during the last c. 150 years. Our results also showed that U. longissima was favoured by a continuous old age structure with canopy openness preserved. The importance of detailed reconstructions of specific habitat components is highlighted when relating species presence to habitat change. It is suggested that the use of retrospective methods presented in this study can be helpful in clarifying possible causes for the complex distribution of certain organisms.
Lecidea hercynica, a new montane epiphytic lichen from Germany
Authors: SCHMULL Michaela , HAUCK Markus
Published: October 2005

Lecidea hercynica Hauck & Schmull is described as a new species from Germany. It is characterized by a poorly developed or bullate to verrucose, areolate thallus on whitened spots of the substratum, numerous plane to yellowish brown to black, convex apothecia with a persistent margin, Micarea type-like asci, and by the presence of atranorin and protocetraric acid. It does not belong to Lecidea s. str., but is provisionally placed in Lecidea s. lat. until a taxonomic treatment of the whole group has been carried out. Lecidea hercynica is widespread in high-elevation forests of Picea abies in the Harz Mountains, where it grows preferably on decorticated wood in open situations.
A tribute to Oliver Lathe Gilbert
Authors: Purvis O. William
Published: October 2005

Oliver Gilbert was a pioneer, an outstanding field botanist and inspirational scientist. He worked in the broad fields of urban and lichen ecology and had almost 40 years of teaching and research experience within universities. Above all he was very approachable, an excellent teacher and fun to be with. Oliver was a leading figure in the British Lichen Society serving as BLS Bulletin Editor (1980–89 except 1987), President (1976–77) and was a frequent Council Member. He was elected an Honorary Member in 1997 and received the prestigious Ursula Duncan Award in January 2004. Oliver had an exceptional ability to find rare and interesting lichens and plant communities that others had overlooked and he constantly challenged conventional wisdom that particular habitats were uninteresting, especially urban habitats. His ecological ‘field craft’ skills were equally legendary. Passion for field work and British Lichen Society field meetings led him to organize a small grant awards scheme to stimulate others to attend field meetings and to submit their results for publication in the BLS Bulletin.
Associations of pre-trauma attributes and trauma exposure with screening positive for PTSD: analysis of a community-based study of 2085 young adults
Authors: PARSLOW RUTH A. , JORM ANTHONY F. , CHRISTENSEN HELEN
Published: October 2005

Background. While pre-trauma personality and mental health measures are risk factors for post-traumatic stress disorder (PTSD), such information is usually obtained following the trauma and can be influenced by post-trauma distress. We used data collected from a community-based survey of young adults before and after a major natural disaster to examine the extent to which participants' traumatic experiences, demographic and pre-trauma risk factors were associated with their screening positive for PTSD when re-interviewed.

Method. A representative selection of 2085 young adults from the Australian Capital Territory and environs, interviewed in 1999 as part of a longitudinal community-based survey, were re-interviewed 3–18 months after a major bushfire had occurred in the region. When re-interviewed, they were asked about their experiences of trauma threat, uncontrollable and controllable traumatic experiences and their reaction to the fire. They were also screened for symptoms of fire-related PTSD experienced in the week prior to interview.

Results. Four-fifths of participants were exposed to the trauma with around 50% reporting having experienced uncontrollable traumatic events. Reporting PTSD symptoms was associated with being female, having less education, poorer mental health and higher levels of neuroticism prior to the trauma. Particular fire experiences, including being evacuated and feeling very distressed during the disaster, were more strongly associated with PTSD symptoms compared with pre-trauma measures.

Conclusions. While demographic and pre-trauma mental health increased the likelihood of reporting PTSD symptoms, exposure to trauma threat and reaction to the trauma made greater contributions in explaining such symptoms as a result of this disaster.
Cutaneous glucocorticoid receptor sensitivity and pro-inflammatory cytokine levels in antidepressant-resistant depression
Authors: FITZGERALD PETER , O'BRIEN SINEAD M. , SCULLY PAUL , RIJKERS KIM , SCOTT LUCINDA V. , DINAN TIMOTHY G.
Published: October 2005

Background. There is evidence to indicate that peripheral glucocorticoid receptor (GR) function is reduced in major depression, and a possible molecular explanation for this is the impact of raised pro-inflammatory cytokines. The topical steroid vasoconstriction assay provides a convenient probe of peripheral GR function. The present study sought to assess the sensitivity of peripheral GRs in antidepressant-resistant major depressives and investigate the association between GR sensitivity and circulating plasma cytokines.

Method. Nineteen antidepressant-resistant depressives together with age- and sex-matched healthy controls underwent the steroid vasoconstriction assay using three commercial preparations of corticosteroids containing clobetasol propionate 0·05%, betamethasone valerate 0·1%, and clobetasone butyrate 0·05%, corresponding to very potent, potent, and moderately potent steroid creams respectively. The pro-inflammatory cytokines, tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were measured using enzyme-linked immunosorbent assays. The severity of the depressive episode was assessed using the Hamilton Depression Scale (HAMD).

Results. Depressed subjects had a significantly reduced vasoconstriction response across all three strengths of steroid. They also had significantly higher concentrations of TNF-α and IL-6. There was a significant inverse correlation between TNF-α concentration and vasoconstriction response and also between the HAMD score and vasoconstriction response.

Conclusions. These findings suggest that cutaneous GR function is abnormal in antidepressant-resistant depression, that circulating TNF-α may play a significant role in this abnormality and that the efficacy of topical steroids in antidepressant-resistant depressives is reduced.
Adverse birth outcomes in a malarious area
Authors: KALANDA B. F. , VERHOEFF F. H. , CHIMSUKU L. , HARPER G. , BRABIN B. J.
Published: October 2005

To determine factors associated with fetal growth, preterm delivery and stillbirth in an area of high malaria transmission in Southern Malawi, a cross-sectional study of pregnant women attending and delivering at two study hospitals was undertaken. A total of 243 (17·3%) babies were preterm and 54 (3·7%) stillborn. Intra-uterine growth retardation (IUGR) occurred in 285 (20·3%), of whom 109 (38·2%) were low birthweight and 26 (9·1%) preterm. Factors associated with IUGR were maternal short stature [adjusted odds ratio (AOR) 1·6, 95% confidence interval (CI) 1·0–2·5]; primigravidae (AOR 1·9, 95% CI 1·4–2·7); placental or peripheral malaria at delivery (AOR 1·4, 95% CI 1·0–1·9) and maternal anaemia at recruitment (Hb <8 g/dl) (AOR 1·9, 95% CI 1·3–2·7). Increasing parasite density in the placenta was associated with both IUGR (P=0·008) and prematurity (P=0·02). Factors associated with disproportionate fetal growth were maternal malnutrition [mid-upper arm circumference (MUAC) <23 cm, AOR 1·9, 95% CI 1·0–3·7] and primigravidae (AOR 1·8, 95% CI 1·0–3·1). Preterm delivery and stillbirth were associated with <5 antenatal care visits (AOR 2·2, 95% CI 1·3–3·7 and AOR 3·1, 95% CI 1·4–7·0 respectively) and stillbirth with a positive Venereal Disease Research Laboratory (VDRL) test (AOR 4·7, 95% CI 1·5–14·8). Interventions to reduce poor pregnancy outcomes must reduce the burden of malaria in pregnancy, improve antenatal care and maternal malnutrition.
Survival of a national cohort of hepatitis C virus infected patients, 16 years after exposure
Authors: HARRIS H. E. , RAMSAY M. E. , ANDREWS N. J.
Published: October 2005

The aim of this study was to describe the natural history of HCV after 16 years of infection, in a cohort of individuals who acquired their infections on a known date in the United Kingdom. A total of 924 HCV-infected transfusion recipients (cases) and 475 anti-HCV negative transfusion recipients (controls) were eligible for inclusion in the study. Survival was compared between cases and controls to see if there was any excess mortality attributable to HCV. The results show that all-cause mortality was not significantly different between cases and controls (hazard ratio 1·17, 95% CI 0·92–1·49, P=0·21). However, the risk of death directly from liver disease was higher in cases than controls (hazard ratio 2·71, 95% CI 1·09–6·75, P=0·03). Nearly 30% of those HCV-infected cases who died directly from liver disease were known to have consumed excess alcohol.
North‐south asymmetry of the amplitude of high‐latitude Pc 3–5 pulsations: Observations at conjugate stations
Authors: Obana Yuki , Yoshikawa Akimasa , Olson John V. , Morris Ray J. , Fraser Brian J. , Yumoto Kiyohumi
Published: October 2005

The north‐south asymmetry of the amplitude of ULF pulsations in the Pc 3–5 band is studied using magnetic field data from the magnetically conjugate stations at L ∼ 5.4: Kotzebue (KOT) in the northern hemisphere and Macquarie Island (MCQ) in the southern hemisphere. We obtained the following results for the northward (H) component of magnetic pulsations: (1) The north to south power ratio shows a maximum in the northern winter and a minimum in the northern summer. This “seasonal variation” is stronger at higher frequencies (Pc 3 and Pc 4 frequencies). (2) The north to south power ratio for the Pc 4 and Pc 5 frequency band is basically greater than 1.0 for all seasons. This “positive offset” is stronger at lower frequencies. The “seasonal variation” implies that the magnetohydrodynamic (MHD) waves incident from the magnetosphere are more strongly shielded when the ionospheric conductivity is higher. The “positive offset” may result from the difference of the background magnetic field intensity between KOT and MCQ.
Thermal Emission Spectrometer hyperspectral analyses of proposed paleolake basins on Mars: No evidence for in‐place carbonates
Authors: Stockstill Karen R. , Moersch Jeffrey E. , Ruff Steven W. , Baldridge Alice , Farmer Jack
Published: October 2005

Several studies have described photogeologic evidence for paleolacustrine basins on Mars, mostly within impact craters. If these basins contained persistent standing water in the past, they could still contain deposits of evaporite minerals (e.g., carbonates, sulfates). Many such deposits, if exposed at the surface to a sufficient extent, would be detectable in thermal infrared spectra taken from orbit. Using data from the Mars Global Surveyor Thermal Emission Spectrometer (TES), we have conducted a hyperspectral investigation of 43 putative paleolake basins to search for the spectral signatures of evaporite minerals exposed at a scale comparable to the spatial resolution of a single TES pixel (∼3 × 5 km). Seven basins displaying sufficient surface‐related spectral variation were identified using a principal component analysis on the TES spectral image cube covering the basin and its surroundings and spectral regions of interest (ROIs) were defined. Averaged spectra from ROIs were evaluated using previously developed dust cover index. Those spectra determined to be “dust‐free” were analyzed for composition using linear spectral deconvolution. The same spectra were also analyzed using a spectral ratio and a set of carbonate indices developed in the present work. Most TES spectra in this study were well‐modeled using only previously defined TES spectral end‐members. In addition, the spectral ratios and the carbonate index analyses of these basins indicated that carbonates are not present in abundances greater than the detection limits of these methods. Therefore this study did not find any spectral evidence for evaporite deposits in the basins studied.
Response of sand dunes to variations in tidal flow: Fraser Estuary, Canada
Authors: Kostaschuk Ray , Best Jim
Published: October 2005

The morphology of dunes in rivers and estuaries often lags behind changes in river discharge and neap‐spring tides. This study extends previous research by examining the response of large subtidal dunes in the Fraser Estuary, Canada, to changing flow conditions over a semidiurnal tidal cycle. An acoustic Doppler current profiler (ADCP) is used to measure three‐dimensional velocity profiles and estimate sediment transport and a digital echosounder to measure bed profiles and dune characteristics. Mean flow velocity accelerates from 0.60 to 1.99 m/s and mean flow depth decreases from 15.1 to 12.2 m on the falling tide, followed by a decrease in mean velocity to 0.25 m/s and an increase in depth to 15.25 m on the rising tide. Estimates based on ADCP bottom‐tracking and backscatter, and the sediment transport model of van Rijn (1984a, 1984b, 1984c), indicate that bed‐material sediment transport generally follows the pattern of mean velocity over the tidal cycle. Dune length does not change significantly over the survey period. Changes in dune height, steepness and leeside slope angle precede changes in flow velocity, increasing early in the tidal fall because of scour in dune troughs that is likely caused by increased turbulence resulting from development and expansion of the flow separation/deceleration zone. Erosion of dune crests increases as peak velocity is approached near low tide, resulting in a decrease in dune height. Concentrations of sand in suspension also increase with mean velocity, leading to deposition in troughs and a further reduction in dune height and leeside slope angle. Sand falls out of suspension and drapes the dunes as high tide approaches. Dune length is not in equilibrium with the flow whereas dune height is in equilibrium with the strongest flows that occur around low tide. A comparison of bed‐material transport based on dune migration and the model of van Rijn (1984a, 1984b, 1984c) suggests that the model provides reasonable estimates of bed load in the Estuary, although the model must be used with caution because deposition from suspension also contributes to dune migration.
Leakage effect of printed circuit transmission lines with multilayered dielectric substrate
Authors: Tsuji Mikio , Shigesawa Hiroshi
Published: October 2005

We have proposed here a new structure of printed circuit transmission lines in which the dominant mode leaks power through additional dielectric multilayer without affecting neighboring circuits. Such a structure of a microstrip line has a slot on the ground plane and also has a dielectric multilayer under it. Then the appropriate combination of dielectric constant between dielectric layers produces the leakage into the multilayer. This means that the leaky field does not leak into the substrate of the microstrip line, and then we can get the lossy uniform microstrip line above the critical frequency. We present first the dependence of the structural parameters of the proposed microstrip lines on the leakage properties. We also apply such a structure to slot lines as one of coplanar printed circuit transmission lines and confirm that the leakage effect can be successfully controlled by an additional dielectric multilayer. Finally, we present the experimental results for the microstrip line with the dielectric multilayer to verify the validity of the numerical results.
Reduced ozone loss at the upper edge of the Antarctic Ozone Hole during 2001–2004
Authors: Hoppel Karl , Nedoluha Gerald , Fromm Michael , Allen Douglas , Bevilacqua Richard , Alfred Jerome , Johnson Bryan , König‐Langlo Gert
Published: October 2005

The top edge (20–22 km) of the Antarctic ozone hole has been identified as a good place to detect ozone recovery (D. J. Hofmann et al., 1997). During the first six POAM observation years (1994–1996, 1998–2000), the early October ozone mixing ratio at the top edge of the ozone hole was nearly constant, while during the last four years (2001–2004) it was noticeably greater. The estimated ozone photochemical loss for air sampled at 20–22 km in 2001–2004 was likewise smaller. During 2001–2004, there were fewer PSCs and generally higher temperatures during August and September at 20–22 km than prior years. The increased ozone was due to both reduced photochemical ozone loss (2001, 2003, and 2004) and enhanced adiabatic descent of the ozone profile (2002). Because of the changing meteorological conditions, the ozone changes at the top edge of the hole cannot be easily attributed to changes in chlorine abundance.
Strategies for emission controls to mitigate snowmelt acidification
Authors: Chen Limin , Driscoll Charles T.
Published: October 2005

Elevated atmospheric deposition of strong acids contributes to short‐term/seasonal acidification of surface waters draining sensitive northern forests of North America and Europe during high flow. Reducing atmospheric deposition of NO3− and/or SO42−, therefore, could improve the health of aquatic ecosystems by mitigating episodic acidification. We used an integrated biogeochemical model (PnET‐BGC) to simulate the effects of acidic deposition on seasonal variations in surface water chemistry, and to evaluate emission control scenarios to decrease acidification during snowmelt. Model calculations suggest that historical long‐term inputs of acidic deposition have altered the seasonal patterns in surface water chemistry. Although short‐term increases in NO3− coincide with snowmelt acidification, model simulations indicate reductions in SO42− deposition result in larger benefits than an equivalent reduction in NO3− deposition. Year‐around reductions in NO3− deposition are also more beneficial to the acid‐base status of stream water than summer‐only reductions.
Hybrid simulation of ion cyclotron resonance in the solar wind: Evolution of velocity distribution functions
Authors: Li Xing , Habbal Shadia R.
Published: October 2005

Resonant interaction between ions (oxygen ions O+5 and protons) and ion cyclotron waves is investigated using a one dimensional hybrid code. Ion cyclotron waves are self‐consistently generated by an ion cyclotron anisotropy instability. We focus on the detailed acceleration process of ions. The energization of oxygen ions due to waves is found to have two stages. During the first stage, oxygen ions are energized by ion cyclotron waves in the direction perpendicular to the background magnetic field and can develop extreme high temperature anisotropies with TO⊥/TO∥ ≈ 22 in an initially low beta plasma (beta value at 0.01) with very little parallel heating. During this stage, oxygen ions do not show an appreciable bulk acceleration along the background magnetic field. In the second stage, a large bulk acceleration of oxygen ions as large as 0.3vA, where vA is the Alfvén speed, is observed. Ion cyclotron waves are not able to maintain a high temperature anisotropy as inferred from observations. The nonlinear nature of wave particle interaction produces highly complex velocity distribution functions in the oxygen ions. In contrast, the heating and acceleration behavior of the major species, namely protons, is quite different. The velocity distribution functions of protons are less complex than the oxygen velocity distributions. Protons can also develop a large temperature anisotropy with preferential heating in the perpendicular direction. A bulk acceleration of protons (much smaller than the acceleration of oxygen ions) along the background magnetic field is observed to develop simultaneously with the development of a proton temperature anisotropy.
Unusual long‐period Rayleigh wave radiation from a vertical dip‐slip source: The 7 May 2001 North Sea earthquake
Authors: Selby Neil D. , Eshun Esi , Patton Howard J. , Douglas Alan
Published: October 2005

Crustal structures with a thick, surficial sediment layer with low seismic wave speeds produce a reversal in the polarity of the shear stress eigenfunctions of long‐period Rayleigh waves at shallow depth. Consequently, seismic disturbances with a strong vertical dip‐slip component that are within or just below the sediment layer should generate Rayleigh waves that show a polarity reversal when compared with Rayleigh waves from the same source in a more typical crustal structure. Here the first observation of this unusual behavior is presented by modeling surface waves from the 7 May 2001 North Sea earthquake. A previous study finds a focal mechanism close to vertical dip slip for this earthquake, and suggests that the source is within the 6 km thick sediment layer found in this region. An appropriate structural model is used to generate synthetic seismograms and estimate a double‐couple focal mechanism for the source. The orientation of the fault plane determined here is similar to that found by the previous study; however, the slip direction is opposite, demonstrating that the use of an incorrect structural model has a profound effect on focal mechanism determination for this type of seismic source.
Interannual variability of stratospheric and tropospheric ozone determined from satellite measurements
Authors: Fishman Jack , Creilson John K. , Wozniak Amy E. , Crutzen Paul J.
Published: October 2005

Long‐term satellite records have been used in previous studies to examine both trends and interannual variability (IAV) of ozone in the stratosphere. In this study, we use satellite measurements to produce long‐term records of both tropospheric and stratospheric ozone and we examine the IAV of these data sets. Our analysis of the stratospheric component of these observations is consistent with previous findings for total ozone that show a strong correlation with the quasi‐biennial oscillation (QBO) at low latitudes. For tropospheric ozone, we find that there are strong regional enhancements due to in situ generation from large emissions. The IAV of some of these regional enhancements, on the other hand, are strongly correlated with the phase of El Niño–Southern Oscillation (ENSO) and are consistent with our understanding of how regions of subsidence are more conducive to the in situ production of ozone pollution. The insight gained from this study will hopefully provide a better understanding between prevailing meteorological conditions and the evolution of widespread ozone episodes on shorter timescales with the eventual goal of producing an air quality forecasting capability so that exposure of the human population to elevated levels of ozone can be reduced.
Atomic chlorine concentrations derived from ethane and hydroxyl measurements over the equatorial Pacific Ocean: Implication for dimethyl sulfide and bromine monoxide
Authors: Wingenter Oliver W. , Sive Barkley C. , Blake Nicola J. , Blake Donald R. , Rowland F. Sherwood
Published: October 2005

Atomic chlorine and bromine monoxide concentrations ([Cl] and [BrO]) and dimethyl sulfide (DMS) sea‐air fluxes are estimated from data collected during a Lagrangian flight made near Christmas Island (2°N, 157°W) during August 1996 aboard the NASA P3‐B aircraft. Intensive hydrocarbon sampling began in the surface layer (SL) one‐half hour after sunrise and continued until ∼1300 local solar time. Our empirical model includes in situ observations of hydroxyl [HO] and precise measurements of ethane (C2H6) mixing ratios. Ethane was ∼40 pptv higher in the buffer layer (BuL) than in the SL, thus vertical exchange tended to replace any C2H6 that was photochemically removed in the SL. In spite of this, SL C2H6 mixing ratios decreased significantly during the flight. Using only the measured [HO] and estimated vertical mixing, our mass balance equation cannot explain all of the observed SL C2H6 loss. However, when an initial [Cl] of 8.4 (±2.0) × 104 Cl cm−3, decreasing to 5.7 (±2.0) × 104 Cl cm−3 at midday, is included, the observed and estimated C2H6 values are in excellent agreement. Using our [Cl], we estimate a DMS flux a factor of 2 higher than when HO is the only oxidant considered. This flux estimate, when compared to that derived by Lenschow et al. (1999), suggests that if the differences are real, we may be missing a loss term. Best agreement occurs when an average BrO mixing ratio of 1.3 (±1.3) pptv is included in our mass balance equation.
Parallel bit stream correlation system for very long baseline interferometry
Authors: Kiuchi H.
Published: October 2005

Improvements in sampling and recording technology have made it possible to acquire data at rates of higher than 1 Gbit/s. In very long baseline interferometry, the use of wide‐bandwidth data produces a high SNR, which is proportional to (B is bandwidth and T is integration time). In astronomical applications, wide‐bandwidth data acquisition can be used to detect very small flux densities of cosmic radio sources. It is also useful in geodetic applications. The signal processing of the current correlation processing algorithm is bit serial. The data‐processing speed, however, is restricted by the correlation device clock in serial data processing, and as a result, the device speed prevents the whole (channel) bandwidth from being used for observations. To overcome this problem, a new correlation processing algorithm for parallel bit stream set processing has been developed. This article focuses on how to derive serial data processing algorithms for parallel bit stream.
Biliary lipids, water and cholesterol gallstones
Authors: van Erpecum Karel J.
Published: October 2005

Cholesterol supersaturation, hydrophobic bile salts, pronucleating proteins and impaired gall‐bladder motility may contribute to gallstone pathogenesis. We here show that both gallstone‐susceptible C57L and gallstone‐resistant AKR male inbred mice exhibit supersaturated gall‐bladder biles during early lithogenesis, whereas bile‐salt composition becomes hydrophobic only in susceptible C57L mice. In vitro, cholesterol crystallization occurs depending on relative amounts of lipids; excess cholesterol may exceed solubilizing capacity of mixed bile salt—phospholipid micelles, whereas excess bile salts compared with phospholipids leads to deficient cholesterol‐storage capacity in vesicles. In vivo, bile lipid contents are mainly determined at the level of the hepatocyte canalicular membrane, where specific transport proteins enable lipid secretion [ABCG5/G8 (ATP‐binding cassette transporter G5/G8) for cholesterol, MDR3 (multi‐drug resistant 3) for phospholipid, BSEP (bile salt export pump)]. These transport proteins are regulated by farnesoid X and liver X nuclear receptors. After nascent bile formation, modulation of bile water contents in biliary tract and gall‐bladder exerts critical effects on cholesterol crystallization. During progressive bile concentration (particularly in the fasting gall‐bladder), cholesterol and, preferentially, phospholipid transfer occurs from cholesterol‐unsaturated vesicles to emerging mixed micelles. The remaining unstable cholesterol‐enriched vesicles may nucleate crystals. Various aquaporins have recently been discovered throughout the biliary tract, with potential relevance for gallstone formation.
Expression and localization of two isoforms of AQP10 in human small intestine
Authors: Li Huiping , Kamiie Junichi , Morishita Yoshiyuki , Yoshida Yukata , Yaoita Eishin , Ishibashi Kenichi , Yamamoto Tadashi
Published: October 2005

Background information. AQP10 (aquaporin 10) is a new member of water channels and two different transcripts have been reported. The difference between these transcripts is in the presence or the absence of an insertion of 475 nt, which leads to a translation frame shift resulting in a different termination of amino acid translation and synthesis of a shorter form of AQP10. Thus an AQP10 molecule deduced from the transcript with an insertion has a distinct C‐terminus, different from that translated from the transcript without the insertion. In the present study, we investigated the expression and localization of these AQP10 isoforms.

Results. Two transcripts were expressed in human duodenum and jejunum. Western‐blot analysis using antibodies for these AQP10 isoforms immunoblotted two bands of approx. 35 and 30 kDa respectively. Immunohistochemistry and immunoelectron microscopy demonstrated localization of the AQP10 with an insertion in the capillary endothelium in villi of the small intestine and the isoform without the insertion in the gastro‐entero‐pancrestic endocrine cells.

Conclusion. The different forms of localization of the AQP10 isoforms indicate that they may play different roles in the proximal portion of human small intestine.
Tonoplast vesicles of Beta vulgaris storage root show functional aquaporins regulated by protons
Authors: Sutka Moira , Alleva Karina , Parisi Mario , Amodeo Gabriela
Published: October 2005

Background information. Water is crucial for plant development and growth, and its transport pathways inside a plant are an ongoing topic for study. Plants express a large number of membrane intrinsic proteins whose role is now being re‐evaluated by considering not only the control of the overall plant water balance but also in adaptation to environmental challenges that may affect their physiology. In particular, we focused our work on water movements across the root cell TP (tonoplast), the delimiting membrane of the vacuole. This major organelle plays a central role in osmoregulation.

Results. An enriched fraction of TP vesicles from Beta vulgaris (red beet) storage roots obtained by a conventional method was used to characterize its water permeability properties by means of the stopped‐flow technique. The preparation showed high water permeability (485 μm·s−1), consistent with values reported in the literature. The water permeability was strongly blocked by HgCl2 (reduced to 16%) and its energy activation was low. These observations allow us to postulate the presence of functional water channels in this preparation. Moreover, Western‐blot analysis demonstrated the presence of a tonoplast intrinsic protein. With the purpose of studying the regulation of water channels, TP vesicles were exposed to different acidic pH media. When the pH of a medium was low (pH 5.6), the water permeability exhibited a 42% inhibition.

Conclusions. Our findings prove that although almost all water channels present in the TP vesicles of B. vulgaris root are sensitive to HgCl2, not all are inhibited by pH. This interesting selectivity to acidification of the medium could play a role in adapting the water balance in the cell‐to‐cell pathway.
There's no place like WormBase: an indispensable resource for Caenorhabditis elegans researchers
Authors: O'Connell Kevin
Published: October 2005

The nematode Caenorhabditis elegans is used extensively by scientists to study a wide variety of biological processes and is one of the most thoroughly characterized animals. Over the years, the community of C. elegans researchers has generated a wealth of information on the genetics, development, behaviour, and cellular and molecular biology of the worm. This body of data has grown even larger with the recent application of high throughput screening methodology to study gene function, expression and interactions. WormBase (http:www.wormbase.org) is the primary online source of biological data on C. elegans and related nematodes. Equipped with an assortment of powerful search tools, WormBase allows users to quickly extract a variety of information, including data on individual genes, DNA sequence, cell lineage and literature citations. As the database is well maintained and the functionalities constantly modified in response to evolving researcher needs, WormBase has become a vital component of the laboratories studying the worm and a model for other biological databases.
Liver fatty-acid-binding protein (L-FABP) gene ablation alters liver bile acid metabolism in male mice
Authors: Martin Gregory G. , Atshaves Barbara P. , Mcintosh Avery L. , Mackie John T. , Kier Ann B. , Schroeder Friedhelm
Published: October 2005

Although the physiological roles of the individual bile acid synthetic enzymes have been extensively examined, relatively little is known regarding the function of intracellular bile acid-binding proteins. Male L-FABP (liver fatty-acid-binding protein) gene-ablated mice were used to determine a role for L-FABP, the major liver bile acid-binding protein, in bile acid and biliary cholesterol metabolism. First, in control-fed mice L-FABP gene ablation alone increased the total bile acid pool size by 1.5-fold, especially in gall-bladder and liver, but without altering the proportions of bile acid, cholesterol and phospholipid. Loss of liver L-FABP was more than compensated by up-regulation of: other liver cytosolic bile acid-binding proteins [GST (glutathione S-transferase), 3α-HSD (3α-hydroxysteroid dehydrogenase)], key hepatic bile acid synthetic enzymes [CYP7A1 (cholesterol 7α-hydroxylase) and CYP27A1 (sterol 27α-hydroxylase)], membrane bile acid translocases [canalicular BSEP (bile salt export pump), canalicular MRP2 (multidrug resistance associated protein 2), and basolateral/serosal OATP-1 (organic anion transporting polypeptide 1)], and positive alterations in nuclear receptors [more LXRα (liver X receptor α) and less SHP (short heterodimer partner)]. Secondly, L-FABP gene ablation reversed the cholesterol-responsiveness of bile acid metabolic parameters such that total bile acid pool size, especially in gall-bladder and liver, was reduced 4-fold, while the mass of biliary cholesterol increased 1.9-fold. The dramatically reduced bile acid levels in cholesterol-fed male L-FABP (−/−) mice were associated with reduced expression of: (i) liver cytosolic bile acid-binding proteins (L-FABP, GST and 3α-HSD), (ii) hepatic bile acid synthetic enzymes [CYP7A1, CYP27A1 and SCP-x (sterol carrier protein-x/3-ketoacyl-CoA thiolase)] concomitant with decreased positive nuclear receptor alterations (i.e. less LXRα and more SHP), and (iii) membrane bile acid transporters (BSEP, MRP2 and OATP-1). These are the first results suggesting a physiological role for the major cytosolic bile acid-binding protein (L-FABP) in influencing liver bile metabolic phenotype and gall-bladder bile lipids of male mice, especially in response to dietary cholesterol.
Preferential localization of hyperphosphorylated replication protein A to double-strand break repair and checkpoint complexes upon DNA damage
Authors: Wu Xiaoming , Yang Zhengguan , Liu Yiyong , Zou Yue
Published: October 2005

RPA (replication protein A) is an essential factor for DNA DSB (double-strand break) repair and cell cycle checkpoint activation. The 32 kDa subunit of RPA undergoes hyperphosphorylation in response to cellular genotoxic insults. However, the potential involvement of hyperphosphorylated RPA in DSB repair and checkpoint activation remains unclear. Using co-immunoprecipitation assays, we showed that cellular interaction of RPA with two DSB repair factors, Rad51 and Rad52, was predominantly mediated by the hyperphosphorylated species of RPA in cells after UV and camptothecin treatment. Moreover, Rad51 and Rad52 displayed higher affinity for the hyperphosphorylated RPA than native RPA in an in vitro binding assay. Checkpoint kinase ATR (ataxia telangiectasia mutated and Rad3-related) also interacted more efficiently with the hyperphosphorylated RPA than with native RPA following DNA damage. Consistently, immunofluorescence microscopy demonstrated that the hyperphosphorylated RPA was able to co-localize with Rad52 and ATR to form significant nuclear foci in cells. Our results suggest that hyperphosphorylated RPA is preferentially localized to DSB repair and the DNA damage checkpoint complexes in response to DNA damage.
The penta-EF-hand protein ALG-2 interacts directly with the ESCRT-I component TSG101, and Ca2+-dependently co-localizes to aberrant endosomes with dominant-negative AAA ATPase SKD1/Vps4B
Authors: Katoh Keiichi , Suzuki Hidenori , Terasawa Yoshinori , Mizuno Takako , Yasuda Jiro , Shibata Hideki , Maki Masatoshi
Published: October 2005

ALG-2 (apoptosis-linked gene 2) is a Ca2+-binding protein that belongs to the PEF (penta-EF-hand) protein family. Alix (ALG-2-interacting protein X)/AIP1 (ALG-2-interacting protein 1), one of its binding partners, interacts with TSG101 and CHMP4 (charged multivesicular body protein 4), which are components of ESCRT-I (endosomal sorting complex required for transport I) and ESCRT-III respectively. In the present study, we investigated the association between ALG-2 and ESCRT-I. By a GST (glutathione S-transferase) pull-down assay using HEK-293T (human embryonic kidney 293T) cell lysates, endogenous TSG101 and two other exogenously expressed ESCRT-I components [hVps28 (human vacuolar protein sorting 28) and hVps37A] were shown to associate with GST–ALG-2 in the presence of Ca2+. By the yeast two-hybrid assay, however, a positive interaction was observed with only TSG101 among the three ESCRT-I components, suggesting that ALG-2 associates with hVps28 and hVps37A indirectly through TSG101. Using various deletion mutants of TSG101, the central PRR (proline-rich region) was found to be sufficient for interaction with ALG-2 by the GST-pull-down assay. Direct binding of ALG-2 to the TSG101 PRR was demonstrated by an overlay assay using biotin-labelled ALG-2 as a probe. In immunofluorescence microscopic analysis of HeLa cells that overexpressed a GFP (green fluorescent protein)-fused ATPase-defective dominant-negative form of SKD1/Vps4B (GFP–SKD1E235Q), ALG-2 exhibited a punctate distribution at the perinuclear area and co-localized with GFP–SKD1E235Q to aberrant endosomes. This punctate distribution of ALG-2 was markedly diminished by treatment of HeLa cells with a membrane-permeant Ca2+ chelator. Moreover, a Ca2+-binding-defective mutant of ALG-2 did not co-localize with GFP–SKD1E235Q. Our findings suggest that ALG-2 may function as a Ca2+-dependent accessory protein of the endosomal sorting machinery by interacting directly with TSG101 as well as with Alix.
Cyclo-oxygenase-2 contributes to constitutive prostanoid production in rat kidney and brain
Authors: Hétu Pierre-Olivier , Riendeau Denis
Published: October 2005

Cyclo-oxygenases (COXs) catalyse the synthesis of PGH2 (prostaglandin H2), which serves as the common substrate for the production of PGE2, PGD2, PGF2α, prostacyclin (or PGI2) and TXs (thromboxanes). While COX-1 is the major isoform responsible for prostanoid synthesis in healthy tissues, little information is available on the contribution of constitutive COX-2 to the various prostanoid synthetic pathways under non-inflammatory conditions. To evaluate further the role of COX-2 in prostanoid biosynthesis, rats were acutely treated with the selective COX-1 inhibitor SC-560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethylpyrazole] or the selective COX-2 inhibitors MF tricyclic [3-(3,4-difluorophenyl)-4-(4-(methylsulphonyl)phenyl)-2-(5H)-furanone] and DFU [5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2-(5H)-furanone]. Selected tissues were then processed for a complete analysis of their prostanoid content by liquid chromatography MS. Whereas the treatment with SC-560 caused a 60–70% inhibition in the total prostanoid content of most tissues examined, a significant decrease (35–50%) in total prostanoid content following selective COX-2 inhibition was solely detected for kidney and brain tissues. Analysis of the individual prostanoids reveals significant inhibition of 6-oxo-PGF1α, PGE2, PGD2, PGF2α and TXB2 in the kidney and inhibition of all these prostanoids with the exception of PGD2 in the forebrain. These results demonstrate that constitutively expressed COX-2 contributes to the production of prostanoids in kidney and brain for each of the PGE2, PGI2 and TXB2 pathways under non-inflammatory conditions. Approaches to modulate inflammation through specific inhibition of terminal synthases, such as mPGES-1 (microsomal PGE2 synthase-1), thus have the potential to differ from COX-2 inhibitors and non-selective non-steroidal anti-inflammatory drugs with regard to effects on constitutive prostanoid synthesis and on renal function.