bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Variable Sea Surface Temperature on Forecasting Sea Fog and Sea Breezes: A Case Study
Authors: Tang Yongming 
Published: March 2012

AbstractA preliminary study of the effect of sea surface temperature (SST) temporal and spatial variability on regional coastal weather forecasts is described. A high-resolution numerical weather forecast model from the Met Office is run for the U.K. region with hourly updates of SST data obtained from a shelf sea model. When compared with a control run in which SST is maintained with Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) data, it is found that there are significant differences in the coastal-region forecasts for sea breezes and fog formation. The control run underestimates surface temperature and the strength of the sea breeze when compared with the run with hourly SST updates.
A Linear Theory of Three-Dimensional Land–Sea Breezes
Authors: Jiang Qingfang 
Published: March 2012

Abstract
Land–sea breezes (LSBs) induced by diurnal differential heating are examined using a three-dimensional linear model employing fast Fourier transform with emphasis on the complex coastline shape and geometry, the earth’s rotation, and background wind effects. It has been demonstrated that the low-level vertical motion associated with LSB can be significantly enhanced over a bay (peninsula) because of convergence of perturbations induced by differential heating along a seaward concave (convex) coastline. The dependence of surface winds and vertical motion patterns and their evolutions on the coastline geometries such as the width and the aspect ratio of the bay, the earth’s rotation, and the background winds are investigated.
The LSB induced by an isolated tropical island is characterized by onshore flow and ascent over the island in the afternoon to early evening, with a reversal of direction from midnight to early morning. The diurnal heating–induced vertical motion is greatly enhanced over the island and weakened offshore because of the convergence and divergence of perturbations. In the presence of background flow, stronger diurnal perturbations are found at the downwind side of the island, which can extend far downstream associated with inertia–gravity waves.
Weather Regime Transitions and the Interannual Variability of the North Atlantic Oscillation. Part I: A Likely Connection
Authors: Luo Dehai , Cha Jing , Feldstein Steven B. 
Published: March 2012

Abstract
In this study, the relationship between weather regime transitions and the interannual variability of the North Atlantic Oscillation (NAO) in winter during 1978–2008 is examined by using a statistical approach. Four classical weather regimes—the two phases of the NAO (NAO+, NAO−) and the Scandinavian blocking and Atlantic ridge patterns—are obtained with k-means cluster analysis. Observations show that the transition between the NAO+ and NAO− regimes is markedly different between 1978–90 (P1) and 1991–2008 (P2). Within P1 (P2), the frequency of the NAO− to NAO+ (NAO+ to NAO−) transition events is almost twice that of the NAO+ to NAO− (NAO− to NAO+) transition events. On this basis, further cluster analysis performed for two cases with and without NAO transition events indicates that within P1 (P2) the NAO+ (NAO−) anomaly is markedly enhanced as the NAO− to NAO+ (NAO+ to NAO−) transitions take place. Furthermore, the NAO regime transition is found to be more likely to enhance the eastward shift of the NAO+ (NAO−) anomaly. Thus, it is hypothesized that the interannual change in the winter-mean NAO index from P1 to P2 is related to the intraseasonal NAO− to NAO+ (NAO+ to NAO−) transition events during P1 (P2) because of the variation of the NAO pattern in intensity, location, and frequency (number of days). This finding is also seen from calculations of the winter monthly mean NAO index with and without NAO regime transitions.
On the Classification of Extreme Atlantic Hurricanes Utilizing Mid-Twentieth-Century Monitoring Capabilities*
Authors: Hagen Andrew B. , Landsea Christopher W. 
Published: March 2012

Abstract
An investigation is conducted to determine how improvements in observing capabilities and technology may have affected scientists’ ability to detect and monitor Saffir–Simpson Hurricane Wind Scale Category 5 hurricanes in the Atlantic Ocean basin during the mid-twentieth century. Previous studies state that there has been an increase in the number of intense hurricanes and attribute this increase to anthropogenic global warming. Other studies claim that the apparent increased hurricane activity is an artifact of better observational capabilities and improved technology for detecting these intense hurricanes. The present study focuses on the 10 most recent Category 5 hurricanes recorded in the Atlantic, from Hurricane Andrew (1992) through Hurricane Felix (2007). These 10 hurricanes are placed into the context of the technology available in the period of 1944–53, the first decade of aircraft reconnaissance. A methodology is created to determine how many of these 10 recent Category 5 hurricanes likely would have been recorded as Category 5 if they had occurred during this period using only the observations that likely would have been available with existing technology and observational networks. Late-1940s and early-1950s best-track intensities are determined for the entire lifetime of these 10 recent Category 5 hurricanes. It is found that likely only 2 of these 10—both Category 5 landfalling hurricanes—would have been recorded as Category 5 hurricanes if they had occurred during the late-1940s period. The results suggest that intensity estimates for extreme tropical cyclones prior to the satellite era are unreliable for trend and variability analysis.
Some Implications of Ekman Layer Dynamics for Cross-Shelf Exchange in the Amundsen Sea
Authors: Wåhlin A. K. , Muench R. D. , Arneborg L. , Björk G. , Ha H. K. , Lee S. H. , Alsén H. 
Published: March 2012

Abstract
The exchange of warm, salty seawater across the continental shelves off West Antarctica leads to subsurface glacial melting at the interface between the ocean and the West Antarctic Ice Sheet. One mechanism that contributes to the cross-shelf transport is Ekman transport induced by along-slope currents over the slope and shelf break. An investigation of this process is applied to the Amundsen Sea shelfbreak region, using recently acquired and historical field data to guide the analyses. Along-slope currents were observed at transects across the eastern and western reaches of the Amundsen slope. Currents in the east flowed eastward, and currents farther west flowed westward. Under the eastward-flowing currents, hydrographic isolines sloped upward paralleling the seabed. In this layer, declining buoyancy forces rather than friction were bringing the velocity to zero at the seabed. The basin water in the eastern part of the shelf was dominated by water originating from 800–1000-m depth off shelf, suggesting that transport of such water across the shelf frequently occurs. The authors show that arrested Ekman layers mechanism can supply deep water to the shelf break in the eastern section, where it has access to the shelf. Because no unmodified off-shelf water was found on the shelf in the western part, bottom layer Ekman transport does not appear a likely mechanism for delivery of warm deep water to the western shelf area. Warming of the warm bottom water was most pronounced on the western shelf, where the deep-water temperature increased by 0.6°C during the past decade.
Potential Vorticity Diagnosis of the Factors Affecting the Track of Typhoon Sinlaku (2008) and the Impact from Dropwindsonde Data during T-PARC
Authors: Wu Chun-Chieh , Chen Shin-Gan , Yang Chung-Chuan , Lin Po-Hsiung , Aberson Sim D. 
Published: March 2012

Abstract
In 2008, abundant dropwindsonde data were collected during both reconnaissance and surveillance flights in and around tropical cyclones (TCs) in the western North Pacific basin under the framework of The Observing System Research and Predictability Experiment (THORPEX)–Pacific Asian Regional Campaign (T-PARC). The National Centers for Environmental Prediction Global Forecast System (GFS) showed significant track improvements for Typhoon Sinlaku (2008) after the assimilation of dropwindsonde data. For this particular typhoon, the potential vorticity (PV) diagnosis is adopted to understand the key factors affecting the track. A data denial run initialized at 0000 UTC 10 September is examined to evaluate how the extra data collected during T-PARC improve GFS track forecasts.
A quantitative analysis of the steering flow based on the PV diagnosis indicates that the Pacific subtropical high to the east of Sinlaku is a primary factor that advects Sinlaku northwestward, while the monsoon trough plays a secondary role. The assimilation of dropwindsonde data improves the structure and intensity of the initial vortex and maintains the forecast vortex structure in the vertical. The difference in the vertical extent of the vortices could be regarded as a cause for the discrepancy in steering flow between runs with and without the dropwindsonde data. This paper highlights the importance of improved analyses of the vertical TC structure, and thus of a representative steering flow in the deep troposphere during the forecasts.
Handling Nonlinearity in an Ensemble Kalman Filter: Experiments with the Three-Variable Lorenz Model
Authors: Yang Shu-Chih , Kalnay Eugenia , Hunt Brian 
Published: March 2012

Abstract
An ensemble Kalman filter (EnKF) is optimal only for linear models because it assumes Gaussian distributions. A new type of outer loop, different from the one used in 3D and 4D variational data assimilation (Var), is proposed for EnKF to improve its ability to handle nonlinear dynamics, especially for long assimilation windows. The idea of the “running in place” (RIP) algorithm is to increase the observation influence by reusing observations when there is strong nonlinear error growth, and thus improve the ensemble mean and perturbations within the local ensemble transform Kalman filter (LETKF) framework. The “quasi-outer-loop” (QOL) algorithm, proposed here as a simplified version of RIP, aims to improve the ensemble mean so that ensemble perturbations are centered at a more accurate state.
The performances of LETKF–RIP and LETKF–QOL in the presence of nonlinearities are tested with the three-variable Lorenz model. Results show that RIP and QOL allow LETKF to use longer assimilation windows with significant improvement of the analysis accuracy during periods of high nonlinear growth. For low-frequency observations (every 25 time steps, leading to long assimilation windows), and using the optimal inflation, the standard LETKF RMS error is 0.68, whereas for QOL and RIP the RMS errors are 0.47 and 0.35, respectively. This can be compared to the best 4D-Var analysis error of 0.53, obtained by using both the optimal long assimilation windows (75 time steps) and quasi-static variational analysis.
Local and Mesoscale Impacts of Wind Farms as Parameterized in a Mesoscale NWP Model
Authors: Fitch Anna C. , Olson Joseph B. , Lundquist Julie K. , Dudhia Jimy , Gupta Alok K. , Michalakes John , Barstad Idar 
Published: March 2012

Abstract
A new wind farm parameterization has been developed for the mesoscale numerical weather prediction model, the Weather Research and Forecasting model (WRF). The effects of wind turbines are represented by imposing a momentum sink on the mean flow; transferring kinetic energy into electricity and turbulent kinetic energy (TKE). The parameterization improves upon previous models, basing the atmospheric drag of turbines on the thrust coefficient of a modern commercial turbine. In addition, the source of TKE varies with wind speed, reflecting the amount of energy extracted from the atmosphere by the turbines that does not produce electrical energy.
Analyses of idealized simulations of a large offshore wind farm are presented to highlight the perturbation induced by the wind farm and its interaction with the atmospheric boundary layer (BL). A wind speed deficit extended throughout the depth of the neutral boundary layer, above and downstream from the farm, with a long wake of 60-km e-folding distance. Within the farm the wind speed deficit reached a maximum reduction of 16%. A maximum increase of TKE, by nearly a factor of 7, was located within the farm. The increase in TKE extended to the top of the BL above the farm due to vertical transport and wind shear, significantly enhancing turbulent momentum fluxes. The TKE increased by a factor of 2 near the surface within the farm. Near-surface winds accelerated by up to 11%. These results are consistent with the few results available from observations and large-eddy simulations, indicating this parameterization provides a reasonable means of exploring potential downwind impacts of large wind farms.
Quadriceps function in anterior cruciate ligament-deficient knees exercising with transcutaneous electrical nerve stimulation and cryotherapy: a randomized controlled study
Authors: Hart Joseph M , Kuenze Christopher M , Pietrosimone Brian G , Ingersoll Christopher D 
Published: March 2012

Objective: To compare strength and quadriceps muscle activation in anterior cruciate ligament-deficient patients who underwent a two-week rehabilitation exercise program using TENS or cryotherapy. Design: Randomized, controlled study. Setting: Clinical research laboratory. Subjects: Thirty patients: 20 males, 10 females, 31.6 (13.0) years, 172.8 (10.0) cm, 75.8 (13.0) kg with diagnosed tear of the anterior cruciate ligament. Interventions: All patients attended four sessions of supervised quadriceps strengthening exercises over two weeks, prior to reconstruction surgery. Patients were randomly allocated ( n = 10/group) to receive exercises alone, exercise while wearing a sensory transcutaneous electrical nerve stimulation (TENS) device on the knee joint for the duration of each daily session, or 20 minutes of knee joint cryotherapy immediately prior to each daily exercise session. Main measures: Normalized knee extension force and quadriceps central activation ratio were measured before and after the first supervised treatment session and within 24 hours of the last session. Results: When accounting for differences in baseline measures, there were no statistically significant group differences immediately following the first exercise session for knee extension force ( P = 0.10) or central activation ratio ( P = 0.30) nor were there statistically significant group differences after the two-week intervention for knee extension force ( P = 0.92) or central activation ratio ( P = 0.94). Effect sizes for the change in knee extension force and central activation ratio after two weeks of therapy were all large. Conclusions: Quadriceps strength and central activation in anterior cruciate ligament deficient patients improved after two weeks of rehabilitaiton exercises, however, there were no significant differences between treatment groups.
Association of ACE I/D gene polymorphism with vesicoureteral reflux susceptibility in children: a meta-analysis
Authors: Zhou Tian-Biao , Lin Na , Liu Yun-Guang , Qin Yuan-Han , Shao Ming-Bin , Peng Dan-Dan 
Published: March 2012

Background and objective: Many studies have been conducted to investigate the association between angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) gene polymorphism and vesicoureteral reflux (VUR) susceptibility. However, the results from those studies are still conflicting. We performed a meta-analysis of studies relating the ACE I/D gene polymorphism to the risk of VUR. Method: We searched the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) as of 1 March 2011, and recruited the eligible investigations for this meta-analysis. Results: Ten investigations were identified for the analysis of association between ACE I/D gene polymorphism and VUR risk: six in Caucasians, three in East-Asians and one in a Turkish population. All the investigations were performed in children. There was no marked association between ACE I/D gene polymorphism and VUR susceptibility/renal scar for overall populations, Caucasians and East-Asians. In the Turkish population, D allele and DD genotype were associated with the VUR susceptibility/renal scar. Furthermore, ACE I/D gene polymorphism was not associated with VUR progression. Conclusions: D allele and DD genotype are risk factors for the VUR susceptibility/renal scar in Turkish children. However, more case-control association investigations on larger, stratified populations are required in the future.
Non-negative matrix factorisation methods for the spectral decomposition of MRS data from human brain tumours
Authors: Ortega-Martorell Sandra , Lisboa Paulo JG , Vellido Alfredo , Julià-Sapé Margarida , Arús Carles 
Published: March 2012

Abstract

Background

In-vivo single voxel proton magnetic resonance spectroscopy (SV 1H-MRS), coupled with supervised pattern recognition (PR) methods, has been widely used in clinical studies of discrimination of brain tumour types and follow-up of patients bearing abnormal brain masses. SV 1H-MRS provides useful biochemical information about the metabolic state of tumours and can be performed at short (< 45 ms) or long (> 45 ms) echo time (TE), each with particular advantages. Short-TE spectra are more adequate for detecting lipids, while the long-TE provides a much flatter signal baseline in between peaks but also negative signals for metabolites such as lactate. Both, lipids and lactate, are respectively indicative of specific metabolic processes taking place. Ideally, the information provided by both TE should be of use for clinical purposes. In this study, we characterise the performance of a range of Non-negative Matrix Factorisation (NMF) methods in two respects: first, to derive sources correlated with the mean spectra of known tissue types (tumours and normal tissue); second, taking the best performing NMF method for source separation, we compare its accuracy for class assignment when using the mixing matrix directly as a basis for classification, as against using the method for dimensionality reduction (DR). For this, we used SV 1H-MRS data with positive and negative peaks, from a widely tested SV 1H-MRS human brain tumour database.

Results
The results reported in this paper reveal the advantage of using a recently described variant of NMF, namely Convex-NMF, as an unsupervised method of source extraction from SV1H-MRS. Most of the sources extracted in our experiments closely correspond to the mean spectra of some of the analysed tumour types. This similarity allows accurate diagnostic predictions to be made both in fully unsupervised mode and using Convex-NMF as a DR step previous to standard supervised classification. The obtained results are comparable to, or more accurate than those obtained with supervised techniques.

Conclusions
The unsupervised properties of Convex-NMF place this approach one step ahead of classical label-requiring supervised methods for the discrimination of brain tumour types, as it accounts for their increasingly recognised molecular subtype heterogeneity. The application of Convex-NMF in computer assisted decision support systems is expected to facilitate further improvements in the uptake of MRS-derived information by clinicians.
A biochemical marker panel in MRI-proven hyperacute ischemic stroke-a prospective study
Authors: Knauer Carolin , Knauer Katharina , Müller Susanne , Ludolph Albert C , Bengel Dietmar , Müller Hans P , Huber Roman 
Published: March 2012

Abstract

Background
Computer tomography (CT) is still the fastest and most robust technique to rule out ICH in acute stroke. However CT-sensitivity for detection of ischemic stroke in the hyperacute phase is still relatively low. Moreover the validity of pure clinical judgment is diminished by several stroke imitating diseases (mimics). The "Triage® Stroke Panel", a biochemical multimarker assay, detects Brain Natriuretic Peptide (BNP), D-Dimers (DD), Matrix-Metalloproteinase-9 (MMP-9), and S100B protein and promptly generates a Multimarkerindex of these values (MMX). This index has been licensed for diagnostic purposes as it might increase the validity of the clinical diagnosis to differentiate between stroke imitating diseases and true ischemic strokes. Our aim was to prove whether the panel is a reliable indicating device for the diagnosis of ischemic stroke in a time window of 6 h to fasten the pre- and intrahospital pathway to fibrinolysis.

Methods
We investigated all consecutive patients admitted to our stroke unit during a time period of 5 months. Only patients with clinical investigation, blood sample collection and MRI within six hours from symptom onset were included. Values of biochemical markers were analyzed according to the results of diffusion weighted MR-imaging. In addition MMX-values in ischemic strokes were correlated with the TOAST-criteria. For statistical analysis the SAS Analyst software was used. Correlation coefficients were analyzed and comparison tests for two or more groups were performed. Statistical significance was assumed in case of p < 0.05. Finally a ROC-analysis was performed for the MMX-Index.

Results
In total 174 patients were included into this study (n = 100 strokes, n = 49 mimics, n = 25 transitoric ischemic attacks). In patients with ischemic strokes the mean NIHSS was 7.6 ± 6.2, while the mean DWI-lesion volume was 20.6 ml (range 186.9 to 4.2 ml). According to the MMX or the individual markers there was no statistically significant difference between the group of ischemic strokes and the group of mimics. Moreover the correlation of the index and the DWI-lesion-volume was poor (p = 0.2).

Conclusions
In our setting of acute MRI-proven ischemic stroke the used multimarker-assay (Triage® Stroke Panel) was not of diagnostic validity. We do not recommend to perform this assay as this might lead to a unjustified time delay.
Analysis of SLX4/FANCP in non-BRCA1/2-mutated breast cancer families
Authors: Fernández-Rodríguez Juana , Quiles Francisco , Blanco Ignacio , Teulé Alex , Feliubadaló Lídia , Valle Jesús del , Salinas Mónica , Izquierdo Àngel , Darder Esther , Schindler Detlev , Capellá Gabriel , Brunet Joan , Lázaro Conxi , Pujana Miguel Angel 
Published: March 2012

Abstract

Background
Genes that, when mutated, cause Fanconi anemia or greatly increase breast cancer risk encode for proteins that converge on a homology-directed DNA damage repair process. Mutations in the SLX4 gene, which encodes for a scaffold protein involved in the repair of interstrand cross-links, have recently been identified in unclassified Fanconi anemia patients. A mutation analysis of SLX4 in German or Byelorussian familial cases of breast cancer without detected mutations in BRCA1 or BRCA2 has been completed, with globally negative results.

Methods
The genomic region of SLX4, comprising all exons and exon-intron boundaries, was sequenced in 94 Spanish familial breast cancer cases that match a criterion indicating the potential presence of a highly-penetrant germline mutation, following exclusion of BRCA1 or BRCA2 mutations.

Results
This mutational analysis revealed extensive genetic variation of SLX4, with 21 novel single nucleotide variants; however, none could be linked to a clear alteration of the protein function. Nonetheless, genotyping 10 variants (nine novel, all missense amino acid changes) in a set of controls (138 women and 146 men) did not detect seven of them.

Conclusions
Overall, while the results of this study do not identify clearly pathogenic mutations of SLX4 contributing to breast cancer risk, further genetic analysis, combined with functional assays of the identified rare variants, may be warranted to conclusively assess the potential link with the disease.