bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impacts of Land–Atmosphere Feedbacks on Deep, Moist Convection on the Canadian Prairies
Authors: Brimelow Julian C. , Hanesiak John M. , Burrows William R. 
Published: September 2011

Abstract
The purpose of this study was to focus on how anomalies in the normalized difference vegetation index (NDVI; a proxy for soil moisture) over the Canadian Prairies can condition the convective boundary layer (CBL) so as to inhibit or facilitate thunderstorm activity while also considering the role of synoptic-scale forcing. This study focused on a census agricultural region (CAR) over central Alberta for which we had observed lightning data (proxy for thunderstorms), remotely sensed NDVI data, and in situ rawinsonde data (to quantify impacts of vegetation vigor on the CBL characteristics) for 11 summers from 1999 to 2009. The authors’ data suggest that the occurrence of lightning over the study area is more likely (and is of longer duration) when storms develop in an environment in which the surface and upper-air synoptic-scale forcing are synchronized. On days when surface forcing and midtropospheric ascent are present, storms are more likely to be triggered when NDVI is much above average, compared to when NDVI is much below average. Additionally, the authors found the response of thunderstorm duration to NDVI anomalies to be asymmetric. That is, the response of lightning duration to anomalies in NDVI is marked when NDVI is below average but is not necessarily discernible when NDVI is above average. The authors propose a conceptual model, based largely on observations, that integrates all of the above findings to describe how a reduction in vegetation vigor—in response to soil moisture deficits—modulates the partitioning of available energy into sensible and latent heat fluxes at the surface, thereby modulating lifting condensation level heights, which in turn affect lightning activity.
Assessment of Traditional and New Eigenfunction Bases Applied to Extrapolation of Surface Geostrophic Current Time Series to Below the Surface in an Idealized Primitive Equation Simulation
Authors: Scott Robert B. , Furnival Darran G. 
Published: September 2011

AbstractThree strategies were compared for extrapolating surface geostrophic velocities to below the surface: S1, using only the barotropic or first baroclinic mode; S2, using a fixed or “phase locked” linear combination of the first baroclinic mode and the barotropic mode; and S3, a strategy similar to S2 but using a new set of basis functions. For S2 and S3, the phase locking allows one to impose zero velocity at the seafloor. The new basis functions start from zero at the surface, are not degenerate with respect to the free-surface boundary condition, and represent the adjustment of the pressure at a given depth from density surfaces responding to sea surface height undulations. In idealized primitive equation simulations, strategy S3 had the least error and allowed extrapolation to deeper levels, suggesting the new basis functions performed significantly better than the traditional baroclinic modes. In contrast, strategies S1 and S2 made poor predictions by 400-m depth. Large temporal fluctuations in the fraction of energy in the barotropic and first baroclinic modes could explain the poor predictions by strategies S1 and S2. This brings into question the interpretation of the sea surface height gradients measured by satellite altimetry in terms of first baroclinic mode motions.
Abrupt Transition to Strong Superrotation Driven by Equatorial Wave Resonance in an Idealized GCM
Authors: Arnold Nathan P. , Tziperman Eli , Farrell Brian 
Published: September 2011

Abstract
Persistent superrotation is seen in the atmospheres of other terrestrial bodies (Venus, Titan) but not in that of present Earth, which is distinguished by equatorial easterlies. Nevertheless, superrotation has appeared in numerical simulations of Earth’s atmosphere, from two-layer models to multilevel comprehensive GCMs. Simulations of warm climates that generate enhanced tropical convective variability seem particularly prone to superrotation, which has led to hypotheses that the warmer atmospheres of the early Pliocene and Eocene may have been superrotating, and that the phenomenon may be relevant to future climate projections.
This paper considers a positive feedback leading to superrotation based on an equatorial wave resonance that occurs in a westerly background flow. The authors present simulations with an idealized multilevel GCM forced with a zonally varying equatorial heating, which show abrupt transitions to strongly superrotating states. Linear shallow water theory is used to show that these transitions occur as the superrotating jet velocity approaches the phase speed of free equatorial Rossby wave modes, leading to a resonant amplification of the response to eddy heating and its associated equatorward momentum flux. The resonance and transition are most prominent in simulations where the meridional temperature gradient has been reduced, and hysteresis behavior is seen when the gradient is eliminated completely. No evidence is found in these simulations for the midlatitude wave feedback believed to drive abrupt transitions in two-layer models, and there is only a minor role for the axisymmetric feedback based on vertical advection by the Hadley circulation.
The Predictability of Stratospheric Warming Events: More from the Troposphere or the Stratosphere?
Authors: Sun Lantao , Robinson Walter A. , Chen Gang 
Published: September 2011

Abstract
The roles of the stratosphere and the troposphere in determining the predictability of stratospheric final warming and sudden warming events are evaluated in an idealized atmospheric model. For each stratospheric warming event simulated in the model, a number of forecast experiments are performed from 10 or 20 days prior to the warming onset with perturbations in the troposphere and in the stratosphere separately. It is found that the stratosphere affects predictions of warming onset primarily by providing the initial state of the zonal winds, while the tropospheric initial conditions have a large impact through the generation and propagation of planetary waves. These results correspond to the roles played by the initial zonal flow and the evolution of eddy forcings in a zonally symmetric model. The initial stratospheric zonal flow has some influence on stratospheric wave driving, but in most cases this does not significantly affect the timing of the warming, except when the initial condition is close to the onset date. These results highlight the role of the troposphere in determining stratospheric planetary wave driving and support the importance of tropospheric precursors to the stratospheric warming events.
East Antarctic Landfast Sea Ice Distribution and Variability, 2000–08
Authors: Fraser Alexander D. , Massom Robert A. , Michael Kelvin J. , Galton-Fenzi Benjamin K. , Lieser Jan L. 
Published: September 2011

Abstract
This study presents the first continuous, high spatiotemporal resolution time series of landfast sea ice extent along the East Antarctic coast for the period March 2000–December 2008. The time series was derived from consecutive 20-day cloud-free Moderate Resolution Imaging Spectroradiometer (MODIS) composite images. Fast ice extent across the East Antarctic coast shows a statistically significant (1.43% ±0.30% yr−1) increase. Regionally, there is a strong increase in the Indian Ocean sector (20°–90°E, 4.07% ±0.42% yr−1), and a nonsignificant decrease in the western Pacific Ocean sector (90°–160°E, −0.40% ±0.37% yr−1). An apparent shift from a negative to a positive extent trend is observed in the Indian Ocean sector from 2004. This shift also coincides with a greater amount of interannual variability. No such shift in apparent trend is observed in the western Pacific Ocean sector, where fast ice extent is typically higher and variability lower than the Indian Ocean sector. The limit to the maximum fast ice areal extent imposed by the location of grounded icebergs modulates the shape of the mean annual fast ice extent cycle to give a broad maximum and an abrupt, relatively transient minimum. Ten distinct fast ice regimes are identified, related to variations in bathymetry and coastal configuration. Fast ice is observed to form in bays, on the windward side of large grounded icebergs, between groups of smaller grounded icebergs, between promontories, and upwind of coastal features (e.g., glacier tongues). Analysis of the timing of fast ice maxima and minima is also presented and compared with overall sea ice maxima/minima timing.
The North Atlantic Jet Stream under Climate Change and Its Relation to the NAO and EA Patterns
Authors: Woollings Tim , Blackburn Mike 
Published: September 2011

Abstract
This paper describes recent variations of the North Atlantic eddy-driven jet stream and analyzes the mean response of the jet to anthropogenic forcing in climate models. Jet stream changes are analyzed both using a direct measure of the near-surface westerly wind maximum and using an EOF-based approach. This allows jet stream changes to be related to the widely used leading patterns of variability: the North Atlantic Oscillation (NAO) and East Atlantic (EA) pattern. Viewed in NAO–EA state space, isolines of jet latitude and speed resemble a distorted polar coordinate system, highlighting the dependence of the jet stream quantities on both spatial patterns. Some differences in the results of the two methods are discussed, but both approaches agree on the general characteristics of the climate models. While there is some agreement between models on a poleward shift of the jet stream in response to anthropogenic forcing, there is still considerable spread between different model projections, especially in winter. Furthermore, the model responses to forcing are often weaker than their biases when compared to a reanalysis. Diagnoses of jet stream changes can be sensitive to the methodologies used, and several aspects of this are also discussed.
Concept Tests for a New Wire Flying Vehicle Designed to Achieve High Horizontal Resolution Profiling in Deep Water
Authors: Roman Chris , Hebert Dave 
Published: September 2011

Abstract
Efficiently profiling the water column to achieve both high vertical and horizontal resolution from a moving vessel in deep water is difficult. Current solutions, such as CTD tow-yos, moving vessel profilers, and undulating tow bodies, are limited by ship speed or water depth. As a consequence, it is difficult to obtain oceanographic sections with sufficient resolution to identify many relevant scales over the deeper sections of the water column. This paper presents a new concept for a profiling vehicle that slides up and down a towed wire in a controlled manner using the lift created by wing foils. The wings provide a novel low-power method of propulsion along the cable by using the free stream velocity of the wire moving through the water in similar fashion to a sailboat sailing up wind. Scale model tests show a wide range of achievable profiling glide slopes for tow cable angles between vertical and 45°, and effective isolation of cable strum vibration from the towed vehicle body. The concept is not depth limited and will offer two-dimensional resolution that meets or exceeds current undulating tow bodies over the full water column. Additionally, this system could be used simultaneously with many other deep towed instrument packages to produce complementary datasets.
On the Renormalization of the Covariance Operators
Authors: Yaremchuk Max , Carrier Matthew 
Published: September 2011

Many background error correlation (BEC) models in data assimilation are formulated in terms of a smoothing operator [Formula: see text], which simulates the action of the correlation matrix on a state vector normalized by respective BE variances. Under such formulation, [Formula: see text] has to have a unit diagonal and requires appropriate renormalization by rescaling. The exact computation of the rescaling factors (diagonal elements of [Formula: see text]) is a computationally expensive procedure, which needs an efficient numerical approximation. In this study approximate renormalization techniques based on the Monte Carlo (MC) and Hadamard matrix (HM) methods and on the analytic approximations derived under the assumption of the local homogeneity (LHA) of [Formula: see text] are compared using realistic BEC models designed for oceanographic applications. It is shown that although the accuracy of the MC and HM methods can be improved by additional smoothing, their computational cost remains significantly higher than the LHA method, which is shown to be effective even in the zeroth-order approximation. The next approximation improves the accuracy 1.5–2 times at a moderate increase of CPU time. A heuristic relationship for the smoothing scale in two and three dimensions is proposed for the first-order LHA approximation.
Recurrent Patellar Dislocation in Adolescents
Authors: Zhao Jinzhong , Huangfu Xiaoqiao , He Yaohua , Liu Wenxin 
Published: September 2011

Background: The clinical outcome of arthroscopic medial retinaculum plication (MRP) compared with vastus medialis plasty (VMP) for recurrent patellar dislocation in adolescents is unknown. Hypothesis: Arthroscopic MRP can yield similar results to open VMP for recurrent patellar dislocation in adolescents. Study Design: Randomized controlled clinical trial; Level of evidence, 2. Methods: Sixty adolescent patients were randomly divided into 2 groups to receive arthroscopic MRP and open VMP respectively. The patients were followed up at 3, 6, 12, and 24 months postoperatively and computed tomography (CT) scans were taken immediately after operation and at 12 and 24 months postoperatively to evaluate the position of the patella. Knee function was evaluated at 24 months postoperatively according to the International Knee Documentation Committee (IKDC), Kujala, Lysholm, and Tegner rating scales. For those who underwent operation more than 3 years previously, an additional review was taken to evaluate the latest patellar stability status. Results: The final follow-up time was 56.8 ± 21.5 months (range, 24-92 months) and 59.1 ± 24.7 months (range, 24-88 months), respectively, in the MRP and VMP groups. The CT examination showed that the correction of the patellar position deteriorated over time in both groups. The final patellar position was significantly better than that before surgery in the VMP group, but not in the MRP group. The VMP group had significantly better clinical results at each follow-up compared with the MRP group. The IKDC, Lysholm, Kujala, and Tegner scores were 62.5 ± 6.2, 70.7 ± 5.1, 76.6 ± 4.8, and 3.9 ± 0.7, respectively, in the MRP group, and 71.8 ± 7.1 ( P < .001), 79.4 ± 5.5 ( P < .001), 82.9 ± 4.8 ( P < .001), and 5.1 ± 1.4 ( P < .001), respectively, in the VMP group at the 2-year follow-up. Five patients (17.9%) in the MRP group and 2 patients (7.7%) in the VMP group ( P = .267) experienced episodes of redislocation at the final follow-up. Conclusion: Arthroscopic MRP is less reliable for maintaining the corrected position of the patella and for functional recovery compared with VMP for recurrent patellar dislocation in adolescents.
Slaves to journals, serfs to the web: The use of the internet in newsgathering among European science journalists
Authors: Granado António 
Published: September 2011

This article describes the first survey of European science journalists working for general national print media and news agencies in 14 different countries of the European Union. The survey was carried out through the internet and calls for participation were sent to 208 journalists from 102 different media. Answers were received from 97 science journalists, a response rate of 46.6 percent. After the survey, interviews with 12 of the respondents were conducted. The main conclusion is that not only are science journalists becoming more dependent on scientific journals in their daily reporting, they are also spending a lot of time on the internet – 3.5 hours a day, on average – an activity that increases the concentration on breaking news and prevents them from going outside the newsroom to write more feature stories. In consequence, readers are receiving a distorted image of science as a series of ‘discoveries’ or ‘breakthroughs’, distant from the real daily world of scientists and the scientific process. This dependency on the internet, and on ‘ready-to-write’ press releases from scientific journals, is threatening science journalism, as professionals are controlled by the same embargoes, are using the same sources and visiting the same sites, no matter what country they are working in. This loss of information diversity is a consequence of the introduction of the internet in newsrooms, but also a result of the increasing media awareness of science sources.
Design and implementation of an audit trail in compliance with US regulations
Authors: Jiang Keyuan , Cao Xiang 
Published: September 2011

Background Audit trails have been used widely to ensure quality of study data and have been implemented in computerized clinical trials data systems. Increasingly, there is a need to audit access to study participant identifiable information to provide assurance that study participant privacy is protected and confidentiality is maintained. In the United States, several federal regulations specify how the audit trail function should be implemented. Purpose To describe the development and implementation of a comprehensive audit trail system that meets the regulatory requirements of assuring data quality and integrity and protecting participant privacy and that is also easy to implement and maintain. Methods The audit trail system was designed and developed after we examined regulatory requirements, data access methods, prevailing application architecture, and good security practices. Results Our comprehensive audit trail system was developed and implemented at the database level using a commercially available database management software product. It captures both data access and data changes with the correct user identifier. Documentation of access is initiated automatically in response to either data retrieval or data change at the database level. Limitations Currently, our system has been implemented only on one commercial database management system. Although our audit trail algorithm does not allow for logging aggregate operations, aggregation does not reveal sensitive private participant information. Careful consideration must be given to data items selected for monitoring because selection of all data items using our system can dramatically increase the requirements for computer disk space. Evaluating the criticality and sensitivity of individual data items selected can control the storage requirements for clinical trial audit trail records. Conclusions Our audit trail system is capable of logging data access and data change operations to satisfy regulatory requirements. Our approach is applicable to virtually any data that can be stored in a relational database.
Twenty-one cases of blastic plasmacytoid dendritic cell neoplasm: focus on biallelic locus 9p21.3 deletion
Authors: Lucioni Marco , Novara Francesca , Fiandrino Giacomo , Riboni Roberta , Fanoni Daniele , Arra Mariarosa , Venegoni Luigia , Nicola Marta , Dallera Elena , Arcaini Luca , Onida Francesco , Vezzoli Pamela , Travaglino Erica , Boveri Emanuela , Zuffardi Orsetta , Paulli Marco , Berti Emilio 
Published: September 2011

Abstract
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive malignancy derived from precursors of plasmacytoid dendritic cells. We analyzed 21 cases with array-based comparative genomic hybridization (aCGH). Complete or partial chromosomal losses largely outnumbered the gains, with common deleted regions involving 9p21.3 (CDKN2A/CDKN2B), 13q13.1-q14.3 (RB1), 12p13.2-p13.1 (CDKN1B), 13q11-q12 (LATS2), and 7p12.2 (IKZF1) regions. CDKN2A/CDKN2B deletion was confirmed by FISH. This scenario argues for disruption of cell cycle at G1/S transition, representing a genetic landmark of BPDCN, and possibly contributing to its pathogenesis. Statistical analysis of overall survival in our series highlighted an association of poor outcome with biallelic loss of locus 9p21.3. We suggest that, in the absence of reliable parameters for predicting prognosis in BPDCN other than age, tumor stage, and/or clinical presentation, simple methods, such as FISH for CDKN2A/CDKN2B, could help to identify the most aggressive cases.
Ectopic expression of microRNA-155 enhances innate antiviral immunity against HBV infection in human hepatoma cells
Authors: Su Chenhe , Hou Zhaohua , Zhang Cai , Tian Zhigang , Zhang Jian 
Published: September 2011

Abstract

Background
Host innate antiviral immunity is the first line of defense against viral infection, and is precisely regulated by thousands of genes at various stages, including microRNAs. MicroRNA-155 (miR-155) was found to be up-regualted during viral infection, and influence the host immune response. Besides, the expression of miR-155, or its functional orthologs, may also contribute to viral oncogenesis. HBV is known to cause hepatocellular carcinoma, and there is evidence that attenuated intracellular immune response is the main reason for HBV latency. Thus, we assume miR-155 may affect the immune response during HBV infection in human hepatoma cells.

Results
We found that ectopic expression of miR-155 upregulated the expression of several IFN-inducible antiviral genes in human hepatoma cells. And over-expression of miR-155 suppressed suppressor of cytokine signaling 1 (SOCS1) expression and subsequently enhanced signal transducers and activators of transcription1 (STAT1) and signal transducers and activators of transcription3 (STAT3) phosphorylation. We further demonstrate that ectopic expression of miR-155 inhibits HBV X gene expression to some extent in vitro.

Conclusion
MiR-155 enhances innate antiviral immunity through promoting JAK/STAT signaling pathway by targeting SOCS1, and mildly inhibits HBV infection in human hepatoma cells.
Identification of ionotrophic purinergic receptors in Huh-7 cells and their response towards structural proteins of HCV genotype 3a
Authors: Manzoor Sobia , Idrees Muhammad , Ashraf Javed , Mehmood Azra , Butt Sadia , Fatima Kaneez , Akbar Haji , Rehaman Irshad U , Qadri Ishtiaq 
Published: September 2011

Abstract
Hepatitis C virus (HCV) is a major health problem in developing countries including Pakistan. Chronic HCV infection results in progressive liver disease including fibrosis, cirrhosis, insulin resistance and eventually hepatocellular carcinoma (HCC). Ionotrophic purinergic (P2X) receptors are identified to involve in a spectrum of physiological and pathophysiological processes. However, the role of P2X receptors in HCV liver associated diseases still remains to be investigated. The current study was designed to identify the presence of P2X receptors in human liver cells. Furthermore, it investigates the response of P2X receptors towards HCV structural proteins (E1E2). To determine that how many isoforms of P2X receptors are expressed in human liver cells, human hepatoma cell line (Huh-7) was used. Transcripts (mRNA) of five different isoforms of P2X receptors were identified in Huh-7 cells. To examine the gene expression of identified isoforms of P2X receptors in presence of HCV structural proteins E1E2, Huh-7/E1E2 cell line (stably expressing HCV structural proteins E1E2) was used. The results showed significant increase (6.2 fold) in gene expression of P2X4 receptors in Huh-7/E1E2 cells as compared to control Huh-7 cells. The findings of present study confirmed the presence of transcripts of five different isoforms of P2X receptors in human liver cells and suggest that P2X4 receptors could be represented an important component of the purinergic signaling complex in HCV induced liver pathogenesis.