bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three-Dimensional Model Study of the Antarctic Ozone Hole in 2002 and Comparison with 2000
Authors: Feng W. , Chipperfield M. P. , Roscoe H. K. , Remedios J. J. , Waterfall A. M. , Stiller G. P. , Glatthor N. , Höpfner M. , Wang D.-Y. 
Published: April 2005

Abstract
An offline 3D chemical transport model (CTM) has been used to study the evolution of the Antarctic ozone hole during the sudden warming event of 2002 and to compare it with similar simulations for 2000. The CTM has a detailed stratospheric chemistry scheme and was forced by ECMWF and Met Office analyses. Both sets of meteorological analyses permit the CTM to produce a good simulation of the evolution of the 2002 vortex and its breakup, based on O3 comparisons with Total Ozone Mapping Spectrometer (TOMS) column data, sonde data, and first results from the Environmental Satellite–Michelson Interferometer for Passive Atmospheric Sounding (ENVISAT–MIPAS) instrument. The ozone chemical loss rates in the polar lower stratosphere in September 2002 were generally less than in 2000, because of the smaller average active chlorine, although around the time of the warming, the largest vortex chemical loss rates were similar to those in 2000 (i.e., −2.6 DU day−1 between 12 and 26 km). However, the disturbed vortex of 2002 caused a somewhat larger influence of polar processing on Southern Hemisphere (SH) midlatitudes in September. Overall, the calculations show that the average SH chemical O3 loss (poleward of 30°S) by September was ∼20 DU less in 2002 compared with 2000. A significant contribution to the much larger observed polar O3 column in September 2002 was due to the enhanced descent at the vortex edge and increased horizontal transport, associated with the distorted vortex.
Ozone Forecasts of the Stratospheric Polar Vortex–Splitting Event in September 2002
Authors: Eskes Henk , Segers Arjo , van Velthoven Peter 
Published: April 2005

Abstract
The Southern Hemisphere major warming event in September 2002 has led to a breakup of the vortex in the middle and higher stratosphere and to a corresponding splitting of the ozone hole. Daily 3D ozone forecasts, produced at the Royal Netherlands Meteorological Institute (KNMI) with a tracer transport and assimilation model based on the ECMWF dynamical forecasts, provided an accurate prediction of this event a week prior to the actual breakup of the vortex. The ozone forecast model contains parameterizations for gas phase and heterogeneous chemistry. Initial states for the forecast are obtained from the assimilation of near-real-time ozone data from the Global Ozone Monitoring Experiment (GOME) on European Space Agency (ESA) Remote Sensing Satellite-2 (ERS-2). In this paper, the ozone forecasts and analyses are discussed as produced before, during, and after the event. These fields are compared with ground-based Dobson, ozonesonde, and Total Ozone Mapping Spectrometer (TOMS) observations. The total ozone comparisons show that the location of the vortex edge is generally well described by the 5–7-day forecasts in September and October. The GOME assimilation compared with TOMS shows a good correspondence concerning vortex location and ozone features but also reflects clear differences in the average ozone amount between the two retrieval schemes. The assimilation system produces realistic ozone profiles, apart from a systematic underestimation of ozone around 150 hPa inside the vortex in August–October.
The Ozone Hole of 2002 as Measured by TOMS
Authors: Stolarski Richard S. , McPeters Richard D. , Newman Paul A. 
Published: April 2005

Abstract
Since its discovery in 1985, the ozone hole has been regularly mapped using the data from Total Ozone Mapping Spectrometer (TOMS) instruments on several satellites. The current TOMS, on the Earth Probe satellite, has been taking measurements since 1996. The ozone hole first appeared during the 1980s. Since 1990, the hole has consistently developed during each Antarctic spring over a broad area with the minimum total ozone value reaching about 100 Dobson units (DU; 1 DU = 2.69 × 1016 molecules cm−2) in late September or early October. The year 2002 was markedly different from the past 12 years. A series of strong wave events weakened the South Polar vortex. In late September, a major stratospheric warming took place, reversing the direction of the polar flow and the latitudinal temperature gradient. This warming resulted in a division of the ozone hole into two pieces, one that migrated to lower latitudes and disappeared and one that reformed over the Pole in a weakened form. The development of this year’s unusual ozone hole is shown here and is contrasted to a climatology of the years since 1990. Minimum daily values of total ozone barely reached 150 DU in contrast to values nearer to 100. The area of the ozone hole briefly reached 18 × 106 km2, then dropped rapidly to only 2 × 106 km2, and finally recovered to about 8 × 106 km2 before disappearing in early November. The positive anomaly compared with the last 12 yr near the Pole was accompanied by a smaller negative anomaly north of 45°S.
A Possible Influence of Equatorial Winds on the September 2002 Southern Hemisphere Sudden Warming Event
Authors: Gray Lesley , Norton Warwick , Pascoe Charlotte , Charlton Andrew 
Published: April 2005

Abstract
The stratospheric sudden warming in the Southern Hemisphere (SH) in September 2002 was unexpected for two reasons. First, planetary wave activity in the Southern Hemisphere is very weak, and midwinter warmings have never been observed, at least not since observations of the upper stratosphere became regularly available. Second, the warming occurred in a west phase of the quasi-biennial oscillation (QBO) in the lower stratosphere. This is unexpected because warmings are usually considered to be more likely in the east phase of the QBO, when a zero wind line is present in the winter subtropics and hence confines planetary wave propagation to higher latitudes closer to the polar vortex. At first, this evidence suggests that the sudden warming must therefore be simply a result of anomalously strong planetary wave forcing from the troposphere. However, recent model studies have suggested that the midwinter polar vortex may also be sensitive to the equatorial winds in the upper stratosphere, the region dominated by the semiannual oscillation. In this paper, the time series of equatorial zonal winds from two different data sources, the 40-yr ECMWF Re-Analysis (ERA) and the Met Office assimilated dataset, are reviewed. Both suggest that the equatorial winds in the upper stratosphere above 10 hPa were anomalously easterly in 2002. Idealized model experiments are described in which the modeled equatorial winds were relaxed toward these observations for various years to examine whether the anomalous easterlies in 2002 could influence the timing of a warming event. It is found that the 2002 equatorial winds speed up the evolution of a warming event in the model. Therefore, this study suggests that the anomalous easterlies in the 1–10-hPa region may have been a contributory factor in the development of the observed SH warming. However, it is concluded that it is unlikely that the anomalous equatorial winds alone can explain the 2002 warming event.
Estimating the Uncertainty in a Regional Climate Model Related to Initial and Lateral Boundary Conditions
Authors: Wu Wanli , Lynch Amanda H. , Rivers Aaron 
Published: April 2005

Abstract
There is a growing demand for regional-scale climate predictions and assessments. Quantifying the impacts of uncertainty in initial conditions and lateral boundary forcing data on regional model simulations can potentially add value to the usefulness of regional climate modeling. Results from a regional model depend on the realism of the driving data from either global model outputs or global analyses; therefore, any biases in the driving data will be carried through to the regional model. This study used four popular global analyses and achieved 16 driving datasets by using different interpolation procedures. The spread of the 16 datasets represents a possible range of driving data based on analyses to the regional model. This spread is smaller than typically associated with global climate model realizations of the Arctic climate. Three groups of 16 realizations were conducted using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5) in an Arctic domain, varying both initial and lateral boundary conditions, varying lateral boundary forcing only, and varying initial conditions only. The response of monthly mean atmospheric states to the variations in initial and lateral driving data was investigated.
Uncertainty in the regional model is induced by the interaction between biases from different sources. Because of the nonlinearity of the problem, contributions from initial and lateral boundary conditions are not additive. For monthly mean atmospheric states, biases in lateral boundary conditions generally contribute more to the overall uncertainty than biases in the initial conditions. The impact of initial condition variations decreases with the simulation length while the impact of variations in lateral boundary forcing shows no clear trend. This suggests that the representativeness of the lateral boundary forcing plays a critical role in long-term regional climate modeling. The extent of impact of the driving data uncertainties on regional climate modeling is variable dependent. For some sensitive variables (e.g., precipitation, boundary layer height), even the interior of the model may be significantly affected.
GCM Simulations of the Climate in the Central United States
Authors: Kunkel Kenneth E. , Liang Xin-Zhong 
Published: April 2005

Abstract
A diagnostic analysis of relationships between central U.S. climate characteristics and various flow and scalar fields was used to evaluate nine global coupled ocean–atmosphere general circulation models (CGCMs) participating in the Coupled Model Intercomparison Project (CMIP). To facilitate identification of physical mechanisms causing biases, data from 21 models participating in the Atmospheric Model Intercomparison Project (AMIP) were also used for certain key analyses.
Most models reproduce basic features of the circulation, temperature, and precipitation patterns in the central United States, although no model exhibits small differences from the observationally based data for all characteristics in all seasons. Model ensemble means generally produce better agreement with the observationally based data than any single model. A fall precipitation deficiency, found in all AMIP and CMIP models except the third-generation Hadley Centre CGCM (HadCM3), appears to be related in part to slight biases in the flow on the western flank of the Atlantic subtropical ridge. In the model mean, the ridge at 850 hPa is displaced slightly to the north and to the west, resulting in weaker southerly flow into the central United States.
The CMIP doubled-CO2 transient runs show warming (1°–5°C) for all models and seasons and variable precipitation changes over the central United States. Temperature (precipitation) changes are larger (mostly less) than the variations that are observed in the twentieth century and the model variations in the control simulations.
The Warming of the California Current System: Dynamics and Ecosystem Implications
Authors: Di Lorenzo Emanuele , Miller Arthur J. , Schneider Niklas , McWilliams James C. 
Published: April 2005

Abstract
Long-term changes in the observed temperature and salinity along the southern California coast are studied using a four-dimensional space–time analysis of the 52-yr (1949–2000) California Cooperative Oceanic Fisheries Investigations (CalCOFI) hydrography combined with a sensitivity analysis of an eddy-permitting primitive equation ocean model under various forcing scenarios. An overall warming trend of 1.3°C in the ocean surface, a deepening in the depth of the mean thermocline (18 m), and increased stratification between 1950 and 1999 are found to be primarily forced by large-scale decadal fluctuations in surface heat fluxes combined with horizontal advection by the mean currents. After 1998 the surface heat fluxes suggest the beginning of a period of cooling, consistent with colder observed ocean temperatures. Salinity changes are decoupled from temperature and appear to be controlled locally in the coastal ocean by horizontal advection by anomalous currents. A cooling trend of –0.5°C in SST is driven in the ocean model by the 50-yr NCEP wind reanalysis, which contains a positive trend in upwelling-favorable winds along the southern California coast. A net warming trend of +1°C in SST occurs, however, when the effects of observed surface heat fluxes are included as forcing functions in the model. Within 50–100 km of the coast, the ocean model simulations show that increased stratification/deepening of the thermocline associated with the warming reduces the efficiency of coastal upwelling in advecting subsurface waters to the ocean surface, counteracting any effects of the increased strength of the upwelling winds. Such a reduction in upwelling efficiency leads in the model to a freshening of surface coastal waters. Because salinity and nutrients at the coast have similar distributions this must reflect a reduction of the nutrient supply at the coast, which is manifestly important in explaining the observed decline in zooplankton concentration. The increased winds also drive an intensification of the mean currents of the southern California Current System (SCCS). Model mesoscale eddy variance significantly increases in recent decades in response to both the stronger upwelling winds and the warmer upper-ocean temperatures, suggesting that the stability properties of the SCCS have also changed.
Defective Vav expression and impaired F-actin reorganization in a subset of patients with common variable immunodeficiency characterized by T-cell defects
Authors: Paccani Silvia Rossi , Boncristiano Marianna , Patrussi Laura , Ulivieri Cristina , Wack Andreas , Valensin Silvia , Hirst Tim R. , Amedei Amedeo , del Prete Gianfranco , Telford John L. , D'Elios Mario M. , Baldari Cosima T. 
Published: April 2005

AbstractCommon variable immunodeficiency (CVID) is a primary immune disorder characterized by impaired antibody production, which is in many instances secondary to defective T-cell function (T-CVID). We have previously identified a subset of patients with T-CVID characterized by defective T-cell receptor (TCR)-dependent protein tyrosine phosphorylation. In these patients, ZAP-70 fails to be recruited to the TCR as the result of impaired CD3ζ phosphorylation, which is, however, not dependent on defective Lck expression or activity. Here we show that neither Fyn nor CD45 is affected in these patients. On the other hand, T-CVID T cells show dramatic defects in the Vav/Rac pathway controlling F-actin dynamics. A significant deficiency in Vav protein was indeed observed; in 3 of 4 patients with T-CVID, it was associated with reduced VAV1 mRNA levels. The impairment in Vav expression correlated with defective F-actin reorganization in response to TCR/CD28 coengagement. Furthermore, TCR/CD28-dependent up-regulation of lipid rafts at the cell surface, which requires F-actin dynamics, was impaired in these patients. The actin cytoskeleton defect could be reversed by reconstitution of Vav1 expression in the patients' T cells. Results demonstrate an essential role of Vav in human T cells and strongly suggest Vav insufficiency in T-CVID. (Blood. 2005;106:626-634)
Arf6: a new player in FcγRIIIA lymphocyte-mediated cytotoxicity
Authors: Galandrini Ricciarda , Micucci Federica , Tassi Ilaria , Cifone Maria Grazia , Cinque Benedetta , Piccoli Mario , Frati Luigi , Santoni Angela 
Published: April 2005

AbstractThe activation of phosphoinositide metabolism represents a critical step in the signaling pathways leading to the activation of cytolytic machinery, but its regulation is partially understood. We report here that the stimulation of the low-affinity receptor for immunoglobulin G (IgG) (FcγRIIIA, CD16) on primary human natural killer (NK) cells induces a phosphatidylinositol 3-kinase (PI3K)–dependent activation of the small G protein Arf6. We first demonstrate a functional role for Arf6-dependent signals in the activation of the antibody-dependent cellular cytotoxicity (ADCC) attributable to the control of secretion of lytic granule content. We also show that Arf6 couples CD16 to the lipid-modifying enzymes phosphatidylinositol4phosphate 5-kinase type I alpha (PI5KIα) and phospholipase D (PLD) that are involved in the control of granule secretion; Arf6, but not Rho family small G proteins RhoA and Rac1, is required for receptor-induced PI5KIα membrane targeting as well as for PI5KIα and PLD activation. Our findings suggest that Arf6 plays a crucial role in the generation of a phosphatidylinositol4,5-bisphosphate (PIP2) plasma membrane pool required for cytolytic granule-mediated target cell killing.
Impaired interferon-γ production as a consequence of STAT4 deficiency after autologous hematopoietic stem cell transplantation for lymphoma
Authors: Robertson Michael J. , Chang Hua-Chen , Pelloso David , Kaplan Mark H. 
Published: April 2005

AbstractProduction of interferon γ (IFN-γ) is critical for optimal antitumor immunotherapy in several preclinical animal models. Interleukin-12 (IL-12)–induced IFN-γ production is markedly defective after autologous stem cell transplantation. Quantitative deficiency in CD4 T cells, relative increase in CD25+CD4+ T cells, and bias toward T helper 2 (Th2) differentiation are not the primary mechanisms of defective IFN-γ production. IL-12 receptor β1 (IL-12Rβ1) and IL-12Rβ2 are expressed at equivalent or higher levels on posttransplantation patient peripheral blood mononuclear cells (PBMCs) as compared with control PBMCs. IL-12–induced tyrosine phosphorylation of signal transducer and activator of transcription 4 (STAT4) was undetectable or barely detectable in posttransplantation patient PBMCs, whereas IL-4–induced tyrosine phosphorylation of STAT6 did not differ in posttransplantation patient and control PBMCs. Levels of STAT4 protein were decreased by 97% in posttransplantation patient PBMCs. Levels of STAT4 mRNA were also significantly decreased in posttransplantation patient PBMCs. Incubation with IL-12 and IL-18 in combination partially reversed the defective IFN-γ production by posttransplantation patient PBMCs. IFN-γ production in response to IL-12 plus IL-18 did not require increased expression of STAT4 but was dependent on the activity of p38 mitogen-activated protein kinase (MAPK). These results indicate that defective IFN-γ production is due to an intrinsic deficiency in STAT4 expression by posttransplantation patient lymphocytes and suggest strategies for circumventing this deficiency in cancer immunotherapy.
Human mesenchymal stem cells xenografted directly to rat liver are differentiated into human hepatocytes without fusion
Authors: Sato Yasushi , Araki Hironobu , Kato Junji , Nakamura Kiminori , Kawano Yutaka , Kobune Masayoshi , Sato Tsutomu , Miyanishi Koji , Takayama Tetsuji , Takahashi Minoru , Takimoto Rishu , Iyama Satoshi , Matsunaga Takuya , Ohtani Seiji , Matsuura Akihiro , Hamada Hirofumi , Niitsu Yoshiro 
Published: April 2005

Abstract
Hepatic transdifferentiation of bone marrow cells has been previously demonstrated by intravenous administration of donor cells, which may recirculate to the liver after undergoing proliferation and differentiation in the recipient's bone marrow. In the present study, to elucidate which cellular components of human bone marrow more potently differentiate into hepatocytes, we fractionated human bone marrow cells into mesenchymal stem cells (MSCs), CD34+ cells, and non-MSCs/CD34- cells and examined them by directly xenografting to allylalcohol (AA)-treated rat liver. Hepatocyte-like cells, as revealed by positive immunostaining for human-specific alpha-fetoprotein (AFP), albumin (Alb), cytokeratin 19 (CK19), cytokeratin 18 (CK18), and asialoglycoprotein receptor (AGPR), and by reverse transcription-polymerase chain reaction (RT-PCR) for expression of AFP and Alb mRNA, were observed only in recipient livers with MSC fractions. Cell fusion was not likely involved since both human and rat chromosomes were independently identified by fluorescence in situ hybridization (FISH). The differentiation appeared to follow the process of hepatic ontogeny, reprogramming of gene expression in the genome of MSCs, as evidenced by expression of the AFP gene at an early stage and the albumin gene at a later stage. In conclusion, we have demonstrated that MSCs are the most potent component in hepatic differentiation, as revealed by directly xenografting into rat livers. (Blood. 2005;106:756-763)
High versus standard doses interferon-alpha in the treatment of naïve chronic hepatitis C patients in Taiwan: a 10-year cohort study
Authors: Yu Ming-Lung , Dai Chia-Yen , Chen Shinn-Cherng , Lee Li-Po , Hsieh Ming-Yen , Lin Zu-Yau , Hsieh Ming-Yuh , Wang Liang-Yen , Tsai Jung-Fa , Chang Wen-Yu , Chuang Wan-Long 
Published: April 2005

Abstract
Background
Interferon-alpha monotherapy is effective in less than one-third patients with chronic hepatitis C. The dose-effect, tolerability and durability of interferon-alpha treatment and its long-term effect on the prevention of cirrhosis and hepatocellular carcinoma in naïve Taiwanese patients with chronic hepatitis C have not been well investigated. We conducted the present cohort study treated with high and standard interferon-alpha to illustrate the issues.

Methods
We performed a long-term virologic and histological follow-up of 214 chronic hepatitis C patients treated with interferon-alpha, 3 million units (3-MU, n = 80) or 6-MU (n = 134) thrice weekly for 24 weeks, in Taiwan between 1992 and 2001.

Results
There was no difference in the incidence of discontinuation between 3-MU and 6-MU groups (4/80, 5.0% versus 10/134. 7.5%). The 6-MU group had similar incidence of adverse events with the 3-MU group, except that 6-MU group had significantly higher incidence of psychological manifestations, mainly presented as irritability. The rates of sustained virological response (SVR) were significantly higher in 6-MU regimen (37.1%) than in 3-MU regimen (23.7%, p < 0.05) in per protocol analysis. Based on multivariate analysis, baseline viral load was strongly associated with SVR, followed by hepatitis C virus genotype, interferon-alpha regimen, and liver fibrosis. A histological improvement in necroinflammatory activity, but not in fibrosis was observed in the follow-up biopsy performed 0.5–5.5 years (mean: 1.9 years, n = 51) after end-of-treatment. Among patients without SVR, there was more activity improvement in 6-MU group. The durability of SVR was 100% (18/18) and 97.8% (45/46) for 3-MU and 6-MU group, respectively, in a mean follow-up period of 6.81 years (5.25–9.18 years). For 163 baseline non-cirrhotic patients, 9 of 84 (10.7%) non-responders and 3 of 79 (3.8%) sustained responders progressed to cirrhosis during a mean follow-up period of 5.52 and 5.74 years, respectively (p = 0.067, Kaplan-Meier survival analysis, log-rank test). For all 200 patients, hepatocellular carcinoma was detected in 12 of 113 (10.6%) non-responders and one of 87 (1.1%) sustained responders during a mean follow-up period of 5.67 and 5.73 years, respectively (p < 0.01, Kaplan-Meier survival analysis, log-rank test).

Conclusion
We confirm the dose effect of interferon-alpha in chronic hepatitis C. Six-MU regimen had better efficacy than 3-MU regimen in virologic and histological responses. Both regimens had good tolerability and durability in Taiwan. Sustained response could reduce the incidence of cirrhotic change and hepatocarcinogenesis.