bluuebunny/crossref_metadata_2025 huggingface dataset:
Prognostic Factors and Therapeutic Strategy for Anaplastic Carcinoma of the Thyroid
Authors: Sugitani Iwao , Kasai Nobukatsu , Fujimoto Yoshihide , Yanagisawa Akio
Published: October 2003

Although anaplastic thyroid carcinoma (ATC) is one of the most aggressive malignancies, a few patients survive for a fairly long time after modern intensive treatment. We tried to identify prognostic factors of ATC to assist in deciding on the proper therapeutic strategy in individual patients. Of 47 patients with ATC (1976–1999), 3 patients with “incidental” ATC (largely differentiated thyroid carcinoma with a small region of ATC) were excluded because they had a favorable outcome. The 1‐year survival rate of the remaining 44 patients with clinically distinct ATC was 16%. The presence of acute symptoms, large tumor (> 5 cm), distant metastasis, and leukocytosis (white blood cell count ≥ 10,000/mm3) proved to be significant risk factors. Multivariate analysis by the Cox proportional hazard model showed that these four factors were independent factors for predicting death from ATC. We devised a novel prognostic index (PI) based on the number of these four unfavorable characteristics the patient possessed. Patients with a PI of ≤1 had a 62% survival rate at 6 months, whereas no patients with a PI of ≥3 survived longer than 6 months. All patients with a PI of 4 died from their disease within 3 months. Nine patients received multimodal treatment with a combination of surgery, external irradiation, and chemotherapy and had a long survival (mean 333 ± 68 days; one patient is still alive and tumor‐free), with a mean PI of 0.6. Our PI is useful as a means of selecting patients for aggressive therapy. When the PI is low, multimodal treatment should be attempted to obtain the best survival results; if it is high most patients are too seriously ill to tolerate intensive treatment and palliative therapy is recommended.
Predictive Genetic Screening and Clinical Findings in Multiple Endocrine Neoplasia Type I Families
Authors: Kopp Ina , Bartsch Detlef , Wild Anja , Schilling Thomas , Nies Christoph , Bergenfelz Anders , Rieder Harald , Simon Babette , Rothmund Matthias
Published: October 2003

Germline mutations of the MEN1 gene have been identified as the causative genetic defect of multiple endocrine neoplasia type I (MEN‐I), an autosomal dominantly inherited condition. To establish the basis for predictive family screening we evaluated the spectrum of MEN1 gene mutations in MEN‐I patients treated at our institution. Relatives at risk were subjected to predictive genetic screening after genetic counseling. Gene carriers were subjected to extensive clinical screening for MEN‐I, including biochemical tests for basal hormone concentrations in blood and urine, a standardized meal stimulation test and imaging procedures (ultrasonography, computed tomography, magnetic resonance imaging). Among index patients of 15 independent MEN‐I kindreds, 14 heterozygous MEN1 germline mutations were identified by single‐strand conformational variant analysis (SSCV) and direct DNA sequence analysis. Of 51 individuals at risk, 26 predictively tested relatives with the wild‐type MEN1 gene could be excluded from further screening procedures because they had not inherited the disease. In all previously presumed unaffected relatives with the mutant gene, our extensive clinical screening program revealed at least one manifestation of MEN‐I. Furthermore, 22 additional diagnoses could be established in identified MEN‐I patients. We show that mutation analysis enables predictive genetic screening for MEN‐I families, providing a valuable tool for genetic counseling and clinical management. An extensive clinical screening program focusing on genetically proven individuals at risk allows detection of MEN‐I manifestations at an early, asymptomatic stage of the disease. Controlled, prospective studies are now required to prove whether timely appropriate treatment on the basis of predictive screening might help improve disease‐related quality of life and prolong life expectancy in MEN‐I kindreds.
Comparative NMR studies of diffusional water permeability of red blood cells from different species: XIV. Little Penguin, Eudyptula minor
Authors: Benga G.H. , Chapman B.E. , Cox G.C. , Kuchel P.W.
Published: October 2003

As part of a programme of comparative measurements of diffusional water permeability (Pd) the red blood cells (RBC) from Little Penguin (Eudyptula minor) were studied. The cell dimensions were measured with light and electron microscopy, and by a newly described non‐invasive technique, NMR q‐space analysis. In view of its relative novelty for cell biologists, an overview of this technique is presented. The RBC revealed an ellipsoidal shape that is characteristic of avian RBC, with axis lengths (“diameters”) estimated to be: a=16.0 μm; b=9.6 μm; c=5.0 μm. The values of Pdwere: 2.0×10−3cm s−1at 5 °C, 3.3×10−3cm s−1at 10 °C, 4.6×10−3cm s−1at 15 °C and ∼5.4×10−3cm s−1at 20, 25, 30, 37 and 42 °C.

There was a lack of inhibition of water permeability by p‐chloromercuribenzensulfonate (PCMBS), the well‐known inhibitor of RBC aquaporin. It was notable that in the temperature range 5–20 °C the NMR parameters, and hence the permeability, varied linearly as is found for other species, but at temperatures higher than 20 °C there was no temperature‐dependence of Pd.Consequently, there was an obvious break at ∼20 °C in the Arrhenius plot, of the mean residence life time of water inside the cells, 1/Te, versus temperature. For temperatures less than 20 °C the activation energy Ea,dwas 45.6±6.6 kJ/mol. For temperatures higher than 25 °C Ea,dwas zero. The lack of inhibition of water permeability by PCMBS and the very high value of Ea,dfor diffusive water exchange suggests that the water permeation occurs primarily via the membrane bilayer per se, i.e., there is no aquaporin in Little Penguin RBC. The discontinuity at ∼20 °C in the Arrhenius plot is an interesting finding, not seen before in other species, and we suggest that it reflects a phase transition in the membrane lipids.
Syndecan‐2 expression enhances adhesion and proliferation of stably transfected Swiss 3T3 cells
Authors: Villena Joan , Berndt Christine , Granés Francesc , Reina Manuel , Vilaró Senén
Published: October 2003

Syndecans (heparan sulfate proteoglycans) participate in cell—cell and cell—matrix adhesion and are co‐ and low‐affinity receptors for growth factors and enzymes, respectively. We examined the influence of stable syndecan‐2 expression in Swiss 3T3 cells on cell‐adhesion and proliferation. Higher syndecan‐2 expression changed cell morphology and increased spreading and adhesion in these cells and proliferation induced by FCS and FGF‐2. This emphasizes the role of syndecan‐2 in the integration of signals from soluble and insoluble factors.
An empirical analysis of financial services processes with a front‐office or back‐office orientation
Authors: Safizadeh M.Hossein , Field Joy M , Ritzman Larry P
Published: October 2003

In a departure from most other empirical studies of service organizations, this study employs a lower‐level unit of analysis and explores service processes with front‐office or back‐office orientations. Moreover, unlike past studies, no front‐office process has a corresponding back‐office process in our sample. The analysis of unrelated front‐office and back‐office processes offers a more rigorous examination of the customer contact model. The findings by and large support the premise of this model for breaking up the activities involved in a service delivery process. Our most surprising finding relates to the levers for achieving outstanding performance. The best performers among the processes with a front‐office orientation emphasize capital investment, while the best performers among those with a back‐office orientation embrace higher degrees of labor intensity. It appears that in order to achieve its superior performance, each process type adopts an additional design characteristic commonly attributed to the opposite process type.
Assessment of putative protein targets derived from the SARS genome
Authors: Yan Lisa , Velikanov Mikhail , Flook Paul , Zheng Wenjin , Szalma Sándor , Kahn Scott
Published: October 2003

The ability to rapidly and reliably develop hypotheses on the function of newly discovered protein sequences requires systematic and comprehensive analysis. Such an analysis, embodied within the DS GeneAtlas™ pipeline, has been used to critically evaluate the severe acute respiratory syndrome (SARS) genome with the goal of identifying new potential targets for viral therapeutic intervention. This paper discusses several new functional hypotheses on the roles played by the constituent gene products of SARS, and will serve as an example of how such assignments can be developed or extended on other systems of interest.
Mutational analysis of the KIX domain of CBP reveals residues critical for SREBP binding
Authors: Liu Ya-Ping , Chang Ching-Wen , Chang Kung-Yao
Published: October 2003

Structure‐based mutagenesis was used to probe the binding surface for the activation domain of sterol‐responsive element binding protein (SREBP) in the KIX domain of CREB binding protein. A set of conserved residues scattering in the α2 helix and the extended C‐terminal region of α3 helix in the KIX domain including two arginines previously characterized as a hot spot for cofactor‐mediated methylation was shown to be crucial for SREBP–KIX interaction, and was not essential for phosphorylated KID recognition. Therefore, our results suggest the existence of a SREBP binding site formed by positively charged residues in the C‐terminal part of the extended α3 helix of the KIX domain distinct from the previously identified phosphorylated KID binding site.
Neuropsin (Opn5): a novel opsin identified in mammalian neural tissue1
Authors: Tarttelin Emma E , Bellingham James , Hankins Mark W , Foster Russell G , Lucas Robert J
Published: October 2003

We have cloned and characterised the expression of a new opsin gene, neuropsin (Opn5), in mice and humans. Neuropsin comprises seven exons on mouse chromosome 17. Its deduced protein sequence suggests a polypeptide of 377 amino acids in mice (354 in humans), with many structural features common to all opsins, including a lysine in the seventh transmembrane domain required to form a Schiff base link with retinaldehyde. Neuropsin shares 25–30% amino acid identity with all known opsins, making it the founding member of a new opsin family. It is expressed in the eye, brain, testis and spinal cord.
BiP‐dependent export of cholera toxin from endoplasmic reticulum‐derived microsomes
Authors: Winkeler Alexandra , Gödderz Daniela , Herzog Volker , Schmitz Anton
Published: October 2003

Cholera toxin (CT) is transported from the cell surface to the endoplasmic reticulum (ER) from where it is translocated to the cytosol in a process depending on ATP and luminal ER proteins. To test whether the molecular chaperone BiP (heavy chain binding protein), which is an ER‐luminal ATPase, was one of the required proteins the export of CT was analyzed using ER‐derived CT‐loaded microsomes. The resubstitution of extracted export‐incompetent microsomes with purified BiP was sufficient to restore the export of CT. As BiP protected CT from aggregation it is proposed that BiP maintains CT in a soluble, export‐competent state.
Association of the polymorphisms in the 5′‐untranslated region of PTEN gene with type 2 diabetes in a Japanese population
Authors: Ishihara Hajime , Sasaoka Toshiyasu , Kagawa Syota , Murakami Shihou , Fukui Kazuhito , Kawagishi Yukio , Yamazaki Katsuya , Sato Akira , Iwata Minoru , Urakaze Masaharu , Ishiki Manabu , Wada Tsutomu , Yaguchi Saori , Tsuneki Hiroshi , Kimura Ikuko , Kobayashi Masashi
Published: October 2003

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is known to act as a lipid phosphatase hydrolyzing phosphatidylinositol (PI)(3,4,5)P3 to PI(4,5)P2. Since the PI3‐kinase product, PI(3,4,5)P3, is an important second messenger leading to the metabolic action of insulin, PTEN functions as a potent negative regulator of insulin signaling and its gene is one of the possible candidates involved in susceptibility to the development of type 2 (non‐insulin‐dependent) diabetes. In the present study, we investigated the polymorphisms of the PTEN gene in Japanese patients with type 2 diabetes and non‐diabetic control subjects. We identified three mutations of the gene in the type 2 diabetes patients. Among these mutations, the frequency of the substitution of C with G at position −9 (−9C→G) (SNP1), located in the untranslated region of exon 1, was significantly higher in type 2 diabetic patients than in control subjects. In addition, transfection of the PTEN gene with SNP1 resulted in a significantly higher expression level of PTEN protein compared with that of the wild‐type PTEN gene in Cos1 and Rat1 cells. Furthermore, insulin‐induced phosphorylation of Akt in HIRc cells was decreased more greatly by transfection of SNP1 PTEN gene than that of wild‐type PTEN gene. These findings suggest that the change of C to G at position −9 of the PTEN gene is associated with the insulin resistance of type 2 diabetes due possibly to a potentiated hydrolysis of the PI3‐kinase product.
Quantitative shape measurements of distal volcanic ash
Authors: Riley Colleen M. , Rose William I. , Bluth Gregg J. S.
Published: October 2003

Large‐scale volcanic eruptions produce fine ash (<200 μm) which has a long atmospheric residence time (1 hour or more) and can be transported great distances from the volcanic source, thus, becoming a hazard to aircraft and public health. Ash particles have irregular shapes, so data on particle shape, size, and terminal velocities are needed to understand how the irregular‐shaped particles affect transport processes and radiative transfer measurements. In this study, a methodology was developed to characterize particle shapes, sizes, and terminal velocities for three ash samples of different compositions. The shape and size of 2500 particles from (1) distal fallout (∼100 km) of the 14 October 1974 Fuego eruption (basaltic), (2) the secondary maxima (∼250 km) of the 18 August 1992 Spurr eruption (andesitic), and (3) the Miocene Ash Hollow member, Nebraska (rhyolitic) were measured using image analysis techniques. Samples were sorted into 10 to 19 terminal velocity groups (0.6–59.0 cm/s) using an air elutriation device. Grain‐size distributions for the samples were measured using laser diffraction. Aspect ratio, feret diameter, and perimeter measurements were found to be the most useful descriptors of how particle shape affects terminal velocity. These measurement values show particle shape differs greatly from a sphere (commonly used in models and algorithms). The diameters of ash particles were 10–120% larger than ideal spheres at the same terminal velocity, indicating that irregular particle shape greatly increases drag. Gas‐adsorption derived surface areas are 1 to 2 orders of magnitude higher than calculated surface areas based on measured dimensions and simple geometry, indicating that particle shapes are highly irregular. Correction factors for surface area were derived from the ash sample measurements so that surface areas calculated by assuming spherical particle shapes can be corrected to reflect more realistic values.
Are coronal holes the only source of fast solar wind at solar minimum?
Authors: Hu Y. Q. , Habbal S. R. , Chen Y. , Li X.
Published: October 2003

A two‐dimensional (2‐D) MHD model of an Alfvén‐wave‐driven solar wind in the heliospheric meridional plane is presented whereby the consequences of a magnetic field distribution at the Sun that digresses from the standard dipole structure, often used in 2‐D MHD models, are explored. The latitudinal distribution of open magnetic flux is specified at the solar surface, with a clear distinction between the polar coronal hole and the neighboring quiet Sun. The region of strictly closed magnetic structures at the coronal base is limited in latitude to ±30°. Alfvén waves are assumed to emanate from the solar surface above 30° latitude so as to open the field lines anchored there, as well as heat and accelerate the solar wind. The field lines anchored at the solar surface below 30° latitude, where the plasma is thermally conductive, remain closed, resulting in the formation of the helmet streamer astride the solar equator. The solution obtained is characterized by a helmet streamer in magnetostatic equilibrium, centered at the solar equator, and a steady solar wind outside. With the assumption that the contribution of the polar coronal hole and the quiet Sun to the interplanetary magnetic flux is evenly split between them during solar minimum, a fast wind solution is obtained that matches the latitudinal distribution of the solar wind parameters observed by Ulysses and SOHO and extends from the pole to 9° latitude. The larger fraction (≈60%) of the fast wind (above 30° latitude at 1 AU) emerges from the polar coronal hole, while the remainder is associated with the quiet Sun. While the actual fraction of the fast solar wind originating from polar coronal holes relies on an accurate estimate of the contribution of the open magnetic flux from polar coronal holes to the total IMF flux, this model shows that extending the source of open magnetic flux at the Sun beyond the traditionally assumed polar coronal holes can readily account for the latitudinal distribution of fast wind measured by Ulysses at solar minimum.
A highly spatially and temporally resolved inventory for biogenic isoprene and monoterpene emissions: Model description and application to Great Britain
Authors: Stewart Hope E. , Hewitt C. N. , Bunce R. G. H. , Steinbrecher R. , Smiatek G. , Schoenemeyer T.
Published: October 2003

An inventory describing the fluxes of the volatile organic compound (VOC), isoprene, and the class of VOCs, the monoterpenes, from the biosphere to the atmosphere has been constructed for Great Britain (GB). The controlling parameters were emission potentials from individual plant species, plant species distribution, biomass distribution, temperature, and light intensity. Species distribution and cover data from a national survey of vegetation in 1990 were used. A database of monthly biomass factors was compiled and a qualitative database of VOC emission potentials from vegetation species was updated to a quantitative form. This was used in conjunction with a taxonomic methodology to assign isoprene and monoterpene emission potentials to each plant species extant in GB. Hourly meteorological data for 1998 were calculated using a three‐dimensional nonhydrostatic meteorological mesoscale model (MM5) and these were used to predict the isoprene and monoterpene fluxes in GB in 1998 on a spatial scale of 12 × 12 km and with an hourly temporal resolution. Estimates of annual biogenic isoprene and monoterpene fluxes were 8 and 83 kt, respectively, for the model year. Picea sitchensis (Sitka spruce) is the dominant emitting species in GB, emitting approximately 40% of the annual isoprene and monoterpene fluxes. The dominant emitting regions in GB are coniferous forests in Scotland (isoprene and monoterpenes) and a Populus spp. (poplar) rich area in eastern England (isoprene). Overall uncertainty in the estimates is a maximum of a factor of 4. A sensitivity analysis of the model was used to study the impact of changes in vegetation cover and climate on VOC emission.
Wind‐related features in Gusev crater, Mars
Authors: Greeley Ronald , Kuzmin Ruslan O. , Rafkin Scot C. R. , Michaels Timothy I. , Haberle Robert
Published: October 2003

Gusev crater has a complex history beginning with its formation by an impact in the Noachian Period and subsequent evolution, including erosion and deposition associated with Ma'adim Vallis, which cut through Gusev crater from the south. Various wind‐related features are found on the crater floor, including albedo patterns, bedforms (such as barchan dunes), and elongated hills possibly reflecting erosion by the wind. Comparisons of the orientations of these features with predictions from global and atmospheric models show wind patterns as functions of season and time of day. Strongest global winds occur out of the southeast in the late fall and early winter and appear to be responsible for the formation of a large dark streak that drapes 100 km across the crater floor. On an intermediate‐scale, bright wind streaks correlate with nighttime winds that flow into the crater from the rim and outlying high areas; these streaks are interpreted to be deposits of dust settled from the atmosphere during times of positive atmospheric static stability. Smaller features include various dark streaks and duneforms, the orientations of which are inferred to represent local zones of high wind‐shear surface stress. These features also tend to correlate with strong afternoon upslope winds caused by the uneven heating of the atmosphere across the crater. Thus the large dark streak reflects global‐scale wind patterns, the smaller dark features and duneforms represent flow of strong winds out of the crater in the afternoon, and the small bright streaks represent deposition of dust associated with nighttime flow of wind into the crater. The correlation between the wind regime predicted by the models and the orientations of the aeolian features gives confidence that the models are essentially correct. Because Gusev is a prime candidate landing site for landers, including the Mars Exploration Rovers, understanding the interplay of the atmosphere and the surface (including the erosion and deposition of windblown particles) is important in assessments of the science potential for these missions. Despite the abundance of wind‐related features on the floor of Gusev, only about 1.2% of the proposed landing ellipse area is covered with organized bedforms (e.g., dunes), although mantles of sand and dust are also likely to be present. On the basis of an analysis of random landing points within the ellipse, traverse distances to ridges, ejecta from small craters, and other potential sources of rocks are within 150 m traverse distance for 95% of the touchdown points.
Eos Chasma, Mars: Regional setting for a potential landing site for astrobiology
Authors: Greeley Ronald , Kuzmin Ruslan O. , Nelson David M. , Farmer Jack D.
Published: October 2003

The floor of Eos Chasma, centered at about 13.4°S and 41.5°W at an elevation of −3.5 km, is proposed as a future landing site on Mars. Deposits in this area were derived from a variety of sources, including chaotic terrain (interpreted to reflect the release of subsurface water) and possible paleolake materials, which could shed light on the astrobiological potential of Mars, climate history, and the evolution of the surface. Analyses of the physical properties of the proposed site suggest a rock abundance of 10–18% (based on Viking Orbiter Infrared Thermal Mapper data), set in a matrix of medium to coarse sands (based on Mars Global Surveyor Thermal Emission Spectrometer data), sparse covering by dust (based on albedo measurements), and a surface roughness of <1 to 1.7 m (derived from the Mars Orbiter Laser Altimeter). Although these attributes are within the engineering constraints for current lander designs, models of the atmosphere suggest that wind shear (generated primarily by the proximity to local topography, i.e., the Chasma canyon wall) might preclude the site with current landing systems.
Volcanic evolution of oceanic crust in a Late Ordovician back‐arc basin: The Solund‐Stavfjord Ophiolite Complex, West Norway
Authors: Furnes Harald , Hellevang Helge , Hellevang Bjarte , Skjerlie Kjell Petter , Robins Brian , Dilek Yildirim
Published: October 2003

The stratigraphy of the well‐preserved Solund‐Stavfjord Ophiolite Complex in the West Norwegian Caledonides documents the volcanic evolution of a spreading center in a Late Ordovician back‐arc basin. Basaltic sheet flows, pillow lavas and volcanic breccias are the main components of the ∼470–800 m thick extrusive sequence, and are organized stratigraphically in a cyclic manner. Cyclic units vary in thickness from ∼5 m to 225 m and are typically composed of basal sheet flows or lava flows with large pillows that are succeeded by flows with progressively smaller pillows and volcanic breccias. Thick, independent breccia units also occur in the stratigraphy. In sheet‐flow dominated parts of the sequence the cyclic units are thicker (average 85 m) than in pillow‐dominated parts (average 20 m). Detailed logging of closely spaced profiles (∼1 km or less apart) shows that the proportions of sheet flows, pillow lavas and volcanic breccias varies laterally. Along an axial segment of less than 10 km, the volcanic products change from predominantly sheet flows, reflecting robust volcanic centers, to pillow lavas to volcanic breccias. Sheet‐flow dominated volcanic centers seem to be spaced at intervals of ∼25–30 km, and we tentatively interpret their regularity as an expression of volcanic segmentation at an intermediate‐ to fast spreading center. Observations of modern ocean crust suggest that sheet flows dominate at fast spreading ridges, while pillow lavas dominate at slow‐spreading ridges. Volcanic breccias are apparently rare in both of these environments. These features contrast with the stratigraphy of the Solund‐Stavfjord Ophiolite Complex, where the proportion of different volcanic products varies laterally and volcanic breccias are common. We emphasize the importance of detailed studies of the volcanic stratigraphy of ophiolites, as complements to those of in‐situ oceanic crust, in order to provide a more complete picture of volcanic evolution of oceanic crust in different spreading regimes.
Modeling the electron and proton radiation belts of Saturn
Authors: Santos‐Costa D. , Blanc M. , Maurice S. , Bolton S. J.
Published: October 2003

We present results from a three‐dimensional model of the Saturnian radiation belts. This model draws on pre‐existing physical radiation‐belt models, developed to study the belts of the Earth and Jupiter. In the present work, transport processes and interactions with dust and gas clouds, moons, and plasma are considered to determine the trapped particle distribution in Saturn's inner magnetosphere. The results of the modeling are: absorption by dust is the dominant loss effect in the innermost region while local losses from satellites act as the prominent physical process in the outer part of the inner magnetosphere. Results suggest strong energetic neutral atom emission and weak synchrotron emission. Comparisons between data and model results are presented.
Diagnosis of “forecast‐analysis” differences of a weather prediction system
Authors: Dirren S. , Didone M. , Davies H. C.
Published: October 2003

An alternative approach is set out for the study of the difference between the forecast and contemporaneous analysis fields of a weather prediction system. Illustrations and interpretations are proffered of this difference when viewed in terms of potential vorticity (PV) for both a case study analysis and a single winter's climatology. The results indicate that the approach provides a compact and insightful description of the difference field's dynamics.
Seismogenic zones in Eastern Turkey
Authors: Turkelli Niyazi , Sandvol Eric , Zor Ekrem , Gok Rengin , Bekler Tolga , Al‐Lazki Ali , Karabulut Hayrullah , Kuleli Sadi , Eken Tuna , Gurbuz Cemil , Bayraktutan Salih , Seber Dogan , Barazangi Muawia
Published: October 2003

A 29‐station temporary broadband PASSCAL network was operated from late October 1999 to August 2001 in eastern Turkey in order to decipher the geodynamics of one of the youngest continent‐continent collision zones in the world. This paper focuses on the hypocentral distribution of local earthquakes located during the operation of the network and provides new insights into the active faulting in the Anatolian plateau. A total of 1165 earthquakes were located and classified into four different categories based on the reliability of the locations as established by the data coverage. The accuracy of the locations ranked in the best two categories is estimated to be less than approximately 5 km. The results show that seismic activity in Eastern Turkey is higher than previously documented and there were no subcrustal earthquakes beneath the Arabian‐Eurasian collision zone or beneath the Anatolian plateau during our deployment. This result suggests no or very little underthrusting of the Arabian plate beneath Eurasia. Our results also suggest that the North Anatolian Fault zone extends farther toward the southeast, well beyond the Karliova triple junction, and that a number of unmapped active, seismogenic faults exist in the region. We also observed a possible difference in the seismogenic thickness of the East Anatolian fault zone (EAFZ) and the North Anatolian fault zone (NAFZ).
A systematic global mapping of the radiation field at aviation altitudes
Authors: Stassinopoulos E. G. , Stauffer C. A. , Brucker G. J.
Published: October 2003

This paper presents early results from aircraft measurements made by a Low‐LET Radiation Spectrometer (LoLRS), as part of a long‐range effort to study the complex dynamics of the atmospheric radiation field. For this purpose a comprehensive database is being generated to enable a multivariable global mapping (and eventually modeling) of doses and Linear‐Energy‐Transfer (LET) spectra at aviation altitudes. To accomplish this, a methodical collection of data from the LoLRS (and other instruments) is planned over extended periods of time, in a manner that complements some previous isolated and sporadic measurements by other workers, with the objective to generate a detailed long‐range description of the cosmic‐ray induced particle environment and to study its variability and dependence on atmospheric thickness, magnetic latitude, L‐shell or rigidity, space weather, solar particle events, solar cycle effects, magnetic field variation, diurnal and seasonal effects, and atmospheric weather. Comparison of total doses with predictions is in good agreement.
Use of lognormal distributions in Dst variations for space weather forecast
Authors: Yago K. , Kamide Y.
Published: October 2003

An attempt is made to approximate Dst variations during geomagnetic storms in terms of lognormal distributions. Dst variations for the entire duration of a geomagnetic storm are found to be fitted by a lognormal distribution reasonably well, indicating that by using Dst variations during the main phase, how Dst recovers during the recovery phase can be predicted. This is very useful for space weather predictions. On the other hand, there are quite a few geomagnetic storms that cannot satisfactorily be fitted by lognormal forms because of a long duration of the recovery phase. During the recovery phase of these “abnormal” storms, highly fluctuated interplanetary magnetic fields are seen, such that these events must represent HILDCAAs.
Interpolating the isotopic composition of modern meteoric precipitation
Authors: Bowen Gabriel J. , Revenaugh Justin
Published: October 2003

An accurate representation of the spatial distribution of stable hydrogen and oxygen isotopes in modern precipitation is required for many hydrological, paleoclimate, and ecological applications. No standardized method for achieving such a representation exists, and potential errors associated with previously employed methods are not understood. Using resampling, we test the accuracy of interpolated δD and δ18O estimates made using four methods. Prediction error for all methods is strongly related to number of data and will likely decline with the addition of new data. The best method lowers estimation error by 10–15% relative to others tested and gives an average error, using all available data, ≈2.5% of the global range. We present and interpret global maps of interpolated δD, δ18O, and deuterium excess in precipitation and the 95% confidence intervals for these values created using the optimal method. These depict global and regional patterns, make evident the robustness of interpolated isotopic patterns, and highlight target areas for future precipitation sampling.
Bromide transport before, during, and after colloid mobilization in push‐pull tests and the implications for changes in aquifer properties
Authors: Hellerich Lucas A. , Oates Peter M. , Johnson Carol R. , Nikolaidis Nikolaos P. , Harvey Charles F. , Gschwend Philip M.
Published: October 2003

Bromide breakthrough curves from push‐pull tests were obtained at two wells before, during, and after citrate injections to assess how citrate‐induced colloid mobilization affected physical aquifer transport properties. Tailing and incomplete bromide recoveries (67–95%) could not be fit with a conservative advection/dispersion model, and the results of batch tests using aquifer solids implied bromide was not significantly sorbing. Thus we modeled the bromide returns considering advection, dispersion, and rate‐limited diffusive mass transfer between mobile and immobile regions by fitting αr, the radial dispersivity; α, the rate‐limited mass transfer coefficient; and β, the volumetric ratio of immobile‐to‐mobile domains. Statistical t‐tests indicated that the changes in aquifer transport parameters at a well where colloid mobilization was limited were not significant at a 95% percent confidence level. However, the substantial colloid mobilization at a second well corresponded to significantly decreased αr and β, while increasing α between premobilization and both mobilization and postmobilization. The changes in aquifer parameters and their correlation to the recovered colloidal mass are consistent with the idea that pore‐clogging colloids were mobilized and/or reorganized during citrate injections. The results suggest that flushing a site under the right conditions with citrate could open up immobile regions and substantially reduce remediation time and costs by liberating contaminants whose transport would otherwise be diffusion limited.
Tobacco smoking and gingival neutrophil activity in young adults
Authors: Persson L. , Bergström J. , Gustafsson A. , Âsman B.
Published: October 2003

Abstract. The influence of smoking on the activity of the gingival neutrophils in young periodontally healthy adults was studied. The neutrophil activity was measured in terms of the gingival crevicular fluid (GCF) levels of elastase, lactoferrin (LF), a‐1‐antitrypsin (a‐1‐AT), α‐2‐macroglobulin (α‐2 MG) and protein. 30 healthy dental students with no clinical signs of periodontitis, 15 smokers (8 women and 7 men) aged 20–32 years and 15 non‐smokers (7 women and 8 men) aged 22–31 years, volunteered to take part in the investigation. The gingival inflammation was registered at 6 sites and the GCF volume was collected from the same sites. The GCF volume was measured with a Periotron 6000®. The elastase activity was measured with a chromogenic low molecular substrate and the LF, α‐1‐AT, α‐2‐MG levels were determined with ELISA. The protein concentration was measured by the Bradford method.The results showed a statistically significantly lower GCF volume among smokers as compared to non‐smokers. No significant difference was found in the elastase activity/μl of the GCF supernatant between smokers and non‐smokers but there was a large inter‐individual variation. Nor did the concentrations of LF, α‐1‐AT, 7alpha;‐2‐MG and protein per μl GCF differ significantly between the 2 groups. The results suggest that the influence of smoking on the examined factors associated with neutrophil activity is limited under healthy or slightly inflamed gingival conditions giving only small amounts of GCF.
Retention of fluoride/triclosan in plaque following different modes of administration
Authors: Furuichi Yasushi , Birkhed Dowen
Published: October 2003

Abstract. The aim of the present investigation was to compare: (i) de novo plaque formation, and (ii) fluoride and triclosan concentration in approximal plaque, when a NaF/triclosan/Gantrez®‐containing dentifrice slurry or a mouthrinse were administrated during a 2‐week period of no mechanical plaque control. 10 subjects rinsed for 60 s, 2× daily, for a 14‐day period with one of the following 3 test products: (A) a dentifrice slurry including 1 ml of a NaF/triclosan/Gantrez® dentifrice mixed with 10 ml of tap water, (B) 10 ml of a NaF/triclosan/Gantrez® mouthrinse, or (C) 10 ml of a NaF mouthrinse. De novo plaque formation was assessed on days 4, 7 and 14 using the Turesky's modification of the Quigley and Hein index system. Samples of approximal plaque were obtained immediately after clinical examination on day 14. The samples were analyzed with respect to concentration of fluoride and triclosan using an ion‐specific electrode and a HPLC system, respectively. The 14‐day period was repeated using another test product until all 10 subjects had used all 3 test products in a randomized order. The results showed that: (i) significantly more fluoride was retained in the approximal plaque following periods A and B than period C, and (ii) less plaque was formed during period B than periods A and C.
Action potential conduction block of nerves in vitro by potassium citrate, potassium tartrate and potassium oxalate
Authors: Peacock J. M. , Orchardson R.
Published: October 2003

Abstract. Objectives: potassium salts in desensitising formulations are believed to act by blocking nerve conduction. The aim of this study was to assess the ability of some organic potassium salts to block action potential conduction and to compare their effects with potassium chloride and potassium nitrate. Materials and methods: potassium citrate, oxalate or tartrate were added to Krebs’ solutions to raise the potassium concentration to 8–64 mM. The test solutions were applied to rat spinal nerves in a bath while monitoring the compound action potentials evoked by electrical stimulation. Results: all potassium salts attenuated the compound action potential in a dose‐dependent manner. There were no significant differences between the effects of potassium tartrate and potassium citrate solutions (p>0.1) which caused significantly greater compound action potential attenuation than the same concentrations of potassium oxalate (p<0.05). On the basis of the potassium ion concentration required to cause 50% attenuation of the compound nerve action potential, the relative potencies of the potassium salts citrate=tartrate>oxalate>chloride=nitrate. Conclusion: potassium citrate were: and potassium tartrate were more effective than other potassium salts in blocking nerve conduction and may be more effective dentinal desensitising agents.
Prevalence and distribution of bone defects in moderate and advanced adult periodontitis
Authors: Vrotsos John A. , Parashis Andreas O. , Theofanatos Gerasimos D. , Smulow Jerome B.
Published: October 2003

Abstract. The purpose of the present investigation was to evaluate the prevalence and distribution of different forms of bone defects using direct observation during periodontal surgery. 286 patients with moderate or advanced adult periodontitis diagnosed during clinical and radiographic examination provided a sample of 5476 teeth. After full thickness mucoperiosteal flaps were raised, osseous defects were explored and classified according to their morphology as interdental craters, hemisepta and infrabony defects with 1, 2, 3 or 4 osseous walls. 981 defects were detected; 533 were in the maxilla and 448 in the mandible (15.4% and 22.4%, respectively, of the teeth examined). The posterior mandibular segment had the highest % of teeth with defects (33.8%) followed by the posterior maxillary segment (19.9%). The proportions of teeth with defects in the anterior segments of both arches were similar. The comparison between maxilla and mandible showed a highly significant difference for the posterior segments (p=0.00001) but no difference for the anterior segments (p=0.88). The distribution of defects differed between the maxilla and the mandible, both for the posterior and anterior segments. Craters accounted for almost half the defects, being more prevalent in posterior segments, while hemisepta formed the lowest proportion. Anatomical variations in shape and the original morphology of the alveolar bone between the maxilla and the mandible and the anterior and posterior regions might have been the reason for the differences observed.
Effects of nicotine on periodontal ligament fibroblasts in vitro
Authors: Giannopoulou Catherine , Geinoz Anne , Cimasoni Giorgio
Published: October 2003

Abstract. Cigarette smoking is associated with increased incidence of periodontal disease and poor response to therapy. In the present study, we examined the effects of nicotine on several functions of periodontal ligament fibroblasts (PDLF): proliferation, attachment, alkaline phosphatase production and chemotaxis. Nicotine concentrations varying from 5 ng/ml to 250 μg7sol;ml were tested. Proliferation of cells was studied by the incorporation of 3H‐thymidine, and a dose‐dependent inhibition was observed with concentrations ≥100 ng/ml. Similar results were observed when studying the attachment of the cells on plastic surfaces, using a colorimetric method. The inhibition of attachment was even more evident after 6 h incubation of the cells with nicotine. The activity of alkaline phosphatase, as determined with the substrate p‐nitrophenyl phosphate, in both conditioned medium (CM) and cellular extract (CE), was also significantly decreased in a concentration‐related fashion. Finally, the chemotaxis of PDLF, as examined by a modification of the Boyden's blind‐well chamber technique, was inhibited in a dose‐dependent manner. The degree of inhibition varied from 15% with the lowest concentration of nicotine (50 ng/ml), to almost 90% with the highest (5 μg/ml). The results show that nicotine can have direct adverse effects on various functions of the periodontal cells.
Reconstruction of anatomically complicated periodontal defects using a bioresorbable GTR barrier supported by bone mineral. A 6‐month follow‐up study of 6 cases
Authors: Lundgren D. , Slotte C.
Published: October 2003

Abstract. 6 anatomically complicated periodontal intrabony defects in 6 patients were surgically reconstructed using a bioresorbable GTR barrier supported by cancellous bovine bone mineral. Following cause‐related periodontal treatment, open‐flap surgery was performed to expose the defects. After debridement, the defects were filled with the bone mineral and covered with the barrier. All patients were advised to rinse 2× daily with an 0.2% chlorhexidine digluconate solution and to avoid brushing in the operated area for 6 weeks. The treatment results were evaluated clinically and radiographically 6 months after surgery. All defects healed uneventfully and all patients maintained a high standard of plaque control throughout the study. Probing assessments during surgery showed a bone defect depth and width of on average 7.2 and 2.8 mm. The corresponding measures on presurgical intra‐oral radiographs were 7.9 and 2.6 mm, respectively. Clinical attachment level (CAL) gain averaged 5.3 mm, corresponding to 73% of the original bone defect depth. Radiographically, the defect fill averaged 6.2 mm or 80% of the original radiographic bone defect. It was concluded that the placement of bovine bone mineral beneath bioresorbable GTR barriers facilitates the clinical handling of the barrier and enhances the space for potential periodontal reconstruction of anatomically complicated defects. It remains, however, to be ascertained to what degree the achieved clinical and radiographic results reflect a gain in new connective tissue attachment and alveolar bone.
The effect of a triclosan/copolymer dentifrice on healing after non‐surgical treatment of recurrent periodontitis
Authors: Furuichi Y. , Rosling B. , Volpe A. R. , Lindhe J.
Published: October 2003

Abstract. The present study examined whether the daily use of a triclosan/copolymer dentifrice enhanced healing following non‐surgical periodontal therapy at sites with progressive attachment loss in periodontitis‐susceptible subjects: 60 subjects who had been (i) treated for advanced periodontal disease using nonsurgical means and (ii) had been enrolled, for at least 3–5 years, in a maintenance care program that called for prophylaxis once every 3 months. During the course of this maintenance period, all 60 subjects had suffered recurrent periodontitis at ≥2 sites at several intervals. Following a baseline examination, all 60 subjects received, on an individual basis, detailed instruction in proper self‐performed plaque control methods. They were stratified in 2 balanced groups (test and control groups). The members of the test group were assigned to use a triclosan/copolymer/fluoride‐containing dentifrice, while the control group used a placebo dentifrice. During the following 3 years, all participants were recalled every 3 months for an evaluation of their oral hygiene standard. Re‐examinations were performed after 6, 12, 24 and 36 months. In conjunction with the re‐examinations, sites (loser sites) which exhibited additional probing attachment loss (≥2 mm) were identified. The loser sites were exposed to professional therapy. Thus, the site was anaesthetized and the surface carefully scaled and root planed (S/RP). Alterations regarding probing pocket depth (PPD), probing attachment level (PAL), and bleeding on probing (BoP) that occurred in the interval between S/RP and 36 months were analyzed. In the control group, 126 loser sites, 67 identified at the 12‐month and 59 at the 24‐month examinations, were subjected to S/RP. The corresponding number of loser sites in the test group was 85 (48 at 12 months and 37 at 24 months). At the time of S/RP, about 60% of the sites were BoP (+) in both groups. Following treatment, there was a reduction in the number of sites with gingivitis. While the reduction in the control group was modest (6.8%), in the test group, the improvement was more marked (27.5%). Following S/RP, there was also a reduction of the mean PPD in both groups. This decrease amounted to 1.7 mm in the test group and was significantly (p<0.05) smaller (0.6 mm) in the control. Finally in the interval between S/RP and 36 months, there was an improvement of the probing attachment level in both groups. The mean PAL gain was, however, significantly higher in the test than in the control group (1.8 mm versus 0.7 mm; p<0.01).