bluuebunny/crossref_metadata_2025_split huggingface dataset:
A reduced and limited‐memory preconditioned approach for the 4D‐Var data‐assimilation problem
Authors: Gratton S. , Laloyaux P. , Sartenaer A. , Tshimanga J. 
Published: March 2011

AbstractWe recall a theoretical analysis of the equivalence between the Kalman filter and the four‐dimensional variational (4D‐Var) approach to solve data‐assimilation problems. This result is then extended to cover the comparison of the singular evolutive extended Kalman (SEEK) filter with a reduced variant of the 4D‐Var algorithm. We next concentrate on the solution of the 4D‐Var, which is usually computed with a (truncated) Gauss–Newton algorithm using a preconditioned conjugate‐gradient‐like (CG) method. Motivated by the equivalence of the above‐mentioned algorithms, we explore techniques used in the SEEK filter and based on empirical orthogonal functions (EOFs) as an attempt to accelerate the Gauss–Newton method further. This leads to the development of an appropriate starting point for the CG method, together with that of a powerful limited‐memory preconditioner (LMP), as shown by preliminary numerical experiments performed on a shallow‐water model. Copyright © 2011 Royal Meteorological Society
Characteristics of Ensemble Transform Kalman Filter adaptive sampling guidance for tropical cyclones
Authors: Majumdar Sharanya J. , Chen Shin‐Gan , Wu Chun‐Chieh 
Published: March 2011

AbstractThe Ensemble Transform Kalman Filter (ETKF) is one candidate strategy for targeting observations around tropical cyclones. The characteristics of target areas identified by a revised version of the ETKF are investigated using the THORPEX Interactive Grand Global Ensemble. In order to emphasize sensitivity to the environmental flow, the axisymmetric circulation associated with the tropical cyclone is removed from each ensemble member. The guidance is found to differ markedly from the ensemble variance, and the guidance products based on ensembles from different operational centres often disagree. For the pre‐recurvature stage of typhoon Sinlaku (2008), the targets correspond to asymmetries close to the typhoon, neighbouring features including the adjacent subtropical ridge and a nearby upper‐level trough, and far‐field features including the monsoon trough and areas of flow convergence. During and after recurvature, targets exist in the midlatitude jet upstream and downstream of the typhoon. The midlatitude targets are discernible for forecasts beyond 3 days. The sensitivity to hypothetical observations of wind is more pronounced than those of temperature or specific humidity. The targets based on upper‐level observations correspond to the outflow of the tropical cyclone and nearby and remote jets, while the lower‐level targets correspond to confluent flow near the cyclone. Multiple remote targets are evident, particularly for longer forecast times, and some of these may be spurious. When ensemble forecasts initialized at different times are used for the same case, the characteristics of the guidance differ, although not dramatically. Future priorities include the evaluation of the effects of assimilating observations sampled in target areas versus those in non‐target areas, and the improvement of the data assimilation methodology assumed in the ETKF. Copyright © 2011 Royal Meteorological Society
Forty years of satellite meteorology at Oxford
Authors: Taylor F. W. 
Published: March 2011

AbstractForty years after a similar retrospective on ozone research at Oxford by Dobson in 1968, a review and synthesis is presented of the scientific and technological advances that were possible during the period from 1970 to 2010 as a result of the deployment of a number of innovative instruments on meteorological satellites by a research group in the Atmospheric Physics department at Oxford University. Copyright © 2011 Royal Meteorological Society
Will global warming modify the activity of the Madden–Julian Oscillation?
Authors: Jones Charles , Carvalho Leila M. V. 
Published: March 2011

AbstractThe Madden–Julian Oscillation (MJO) is the most prominent form of tropical intraseasonal variability in the climate system. Observations suggest that warming in the tropical Indian and Pacific Oceans in recent decades may have contributed to increased trends in the annual number of MJO events. A stochastic model is used to project changes in MJO activity under a global warming scenario. The mean number of events per year may rise from ∼3.9 (1948–2008) to ∼5.7 (2049–2099) and the probability of very active years (5 or more events) may significantly increase from 0.51 ± 0.01 (1990–2008) to 0.75 ± 0.01 (2010–2027) and 0.92 ± 0.01 (2094–2099). Copyright © 2011 Royal Meteorological Society
Semifold plans for mixed‐level designs
Authors: Ríos Armando J. , Simpson James R. , Guo Yong 
Published: March 2011

AbstractThis article presents a more efficient method for sequential augmentation of mixed‐level designs. The proposed approach reduces the optimal foldover plan of a mixed‐level design to a semifold plan by selecting half of the treatment combinations of the foldover fraction using exhaustive search and the criterion of general balance metric. The resulting design is a more economic run size augmented fraction that possesses good balance and orthogonality properties for main effects and two‐factor interactions. Three efficient arrays consisting of 20, 24 and 30 runs were selected for the analysis. Efficient arrays composed of a higher number of runs can be semifolded in a similar manner. Copyright © 2011 John Wiley & Sons, Ltd.
A delay‐dependent bounded real lemma for singular LPV systems with time‐variant delay
Authors: Li Fanbiao , Zhang Xian 
Published: March 2011

SUMMARYThis paper is concerned with establishing a delay‐dependent bounded real lemma (BRL) for singular linear parameter‐varying (LPV) systems with time‐variant delay. In terms of linear matrix inequality, a delay‐dependent BRL is presented to ensure singular time‐delay LPV systems to be admissible and satisfy a prescribed H∞ performance level. The BRL is obtained based on the construction of a parameter‐dependent Lyapunov–Krasovskii functional. The effectiveness of the proposed approach is shown by several numerical examples. Copyright © 2011 John Wiley & Sons, Ltd.
Analysis of frazil ice as a geomorphic agent in a frazil pool
Authors: Allard G. , Buffin‐Bélanger T. , Bergeron N. 
Published: March 2011

AbstractFrazil ice forms in open water areas of high turbulent intensity and accumulates downstream along flatter river segments. The activation of production zones, in relation to hydro‐climatic parameters, directly affects the infilling of frazil sinks. Past field investigations have described strong relationships between riverbed scour and undercover frazil accumulation but few have documented the dynamics of bed deformation in relation to the accumulation of frazil ice over an entire winter season. Here, we present the chronology of the development of a hanging dam at a pool section over the 2007–2008 ice period. The characteristics of upstream frazil ice production and ice cover growth is documented using a river corridor approach. At a pool section, undercover frazil ice accumulation behaviour, water level variations, hydro‐climatic conditions and riverbed deformations are also documented. Innovative dynamic bed‐rods integrating three‐axis accelerometer pendant loggers were deployed at the bed to obtain a dynamic measurement of erosional and depositional activity over the frazil pool. Data shows a relation between bedform deformation and ice cover formation. Analysis reveals the spatio‐temporal variation of physical attributes of ice cover, undercover frazil accumulation and bedforms. Collected data is used to analyse the relationship between riverbed deformation and overlying ice forms. Copyright © 2011 John Wiley & Sons, Ltd.
On reducing test length for FSMs with extra states
Authors: Simão Adenilso , Petrenko Alexandre , Yevtushenko Nina 
Published: March 2011

SUMMARYA long‐standing problem when testing from a deterministic finite state machine is to guarantee full fault coverage even if the faults introduce extra states in the implementations. It is well known that such tests should include the sequences in a traversal set which contains all input sequences of length defined by the number of extra states. This paper suggests the SPY method, which helps reduce the length of tests by distributing sequences of the traversal set and reducing test branching. It is also demonstrated that an additional assumption about the implementation under test relaxes the requirement of the complete traversal set. The results of the experimental comparison of the proposed method with an existing method indicate that the resulting reduction can reach 40%. Experimental results suggest that the additional assumption about the implementation can help in further reducing the test suite length. Copyright © 2011 John Wiley & Sons, Ltd.
Numerical and comparative study of earthquake intensity indices in seismic analysis
Authors: Ye Lieping , Ma Qianli , Miao Zhiwei , Guan Hong , Zhuge Yan 
Published: March 2011

AbstractElastoplastic and time‐dependent analysis of seismic structures has become a major analysis technique in popularly accepted performance‐based seismic design. However, the primary difficulty in using this technique is the lack of a unified criterion in the selection of various intensity indices of ground motions. Various earthquake factors influencing the elastoplastic response of seismic structures are highly sophisticated. Hence, it is vitally important to choose an appropriate and comprehensive earthquake intensity index to achieve an accurate correlation with the structural performance. In this study, a total of 30 earthquake intensity indices published in the literature are reviewed and are evaluated through correlation analysis based on 60 ground motion records. Examined herein is the correlation between existing earthquake intensity indices and the seismic responses of elastoplastic single degree‐of‐freedom and multi degree‐of‐freedom systems. The characteristics and applicability of such indices are also discussed in some detail, based on which appropriate earthquake intensity indices are recommended. Copyright © 2011 John Wiley & Sons, Ltd.
Cervical blood perfusion assessed using power Doppler‐derived estimation of fractional moving blood volume: a reproducibility study
Authors: Ierullo A. M. , Fernandez S. , Palacio M. , Gratacos E. , Hernandez‐Andrade E. 
Published: March 2011

AbstractObjectiveTo evaluate the reproducibility of estimation of power Doppler‐derived fractional moving blood volume (FMBV) in the uterine cervix of women with uncomplicated pregnancies.MethodsTwo experienced operators evaluated 30 uncomplicated singleton pregnancies at 20–24 weeks of gestation. The PDU box was positioned in a mid‐sagittal view of the cervix, including the internal os and external os, in the same plane as that in which cervical length is measured. Two consecutive examinations were performed by each operator, in each of which the cervical length was measured and five consecutive good‐quality images with PDU information were obtained. The region of interest (ROI) (cervix) was delineated offline and FMBV, which expresses the percentage of blood occupying the ROI, was calculated with purpose‐designed software. Intra‐ and interobserver intraclass correlation coefficients (ICCs) and mean differences with 95% limits of agreement (LOA) were calculated.ResultsThe median gestational age at examination was 22 + 0 weeks. Measurements (median ± SD) obtained for cervical length and FMBV were as follows: Operator A: 37 ± 7.4 mm and 8.11 ± 2.9%; Operator B: 37.5 ± 9.3 mm and 7.9 ± 3.3%, respectively. The intra‐ and interobserver ICCs for FMBV were 0.88 (95% CI, 0.75–0.94) and 0.82 (95% CI, 0.64–0.94), respectively. There was a mean difference in FMBV measurement between operators of − 0.2 ± 1.75% (95% LOA, − 3.7 to 3.2%).ConclusionsReproducible assessment of cervical blood perfusion through estimation of FMBV can be achieved while cervical length is being measured. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Rpl12p affects the transcription of the PHO pathway high‐affinity inorganic phosphate transporters and repressible phosphatases
Authors: Tu Wen‐Yo , Huang Yu‐Chen , Liu Li‐Fan , Chang Li‐Hsueh , Tam Ming F. 
Published: March 2011

AbstractThe ribosomal protein Rpl12p of Saccharomyces cerevisiae is encoded by duplicated genes, RPL12A and RPL12B. The gene products possess an identical amino acid sequence. Yeast strain 6EA1, which lacks both genes, is viable but exhibits a very slow‐growth phenotype. In this study, 6EA1 cells were transformed with plasmids carrying either RPL12A or RPL12B, and the transcriptional profiles of wild‐type W303, 6EA1 and the transformed cells grown in synthetic complete medium were examined by microarray analysis. Transcription of PHO84, a gene encoding a high‐affinity phosphate transporter, was drastically suppressed in 6EA1. PHO84 expression is induced under phosphate‐limiting conditions. Therefore, cells were grown in low‐phosphate medium and transcripts encoding the PHO pathway proteins were quantified by qRT–PCR. The high‐affinity phosphate transporters and repressible phosphatases were suppressed, while PHO4, a PHO pathway transcription activator, was upregulated in 6EA1. Accordingly, phosphate transport and acidic phosphatase activities were significantly decreased in 6EA1. Addition of RPL12A or RPL12B to 6EA1 largely lessens these effects. We postulate that RPL12 has an extra‐ribosomal function in modulating the transcription of genes that need Pho4p activation. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and Structural Characterization of Four Zinc Complexes Containing 3,5‐Dimethylpyrazole and Carboxylate Ligands
Authors: Jin Shouwen , Wang Daqi 
Published: March 2011

AbstractFour new zinc(II) complexes Zn2(μ‐dmpz)2(Hdmpz)2(L1)2 (1) (Hdmpz = 3,5‐dimethylpyrazole, HL1 = 2‐methyl‐2‐phenoxypropanoic acid), Zn(Hdmpz)2(L2)2 (2) [HL2 = 2‐hydroxy‐5‐(phenyldiazenyl)benzoic acid], Zn2(μ‐dmpz)2(Hdmpz)2(L3)2 (3) [HL3 = 3,4‐(methylenedioxy)benzoic acid], and Zn2(μ‐dmpz)2(Hdmpz)2(L4)2 (4) [HL4 = 3‐(4‐methoxyphenyl)acrylic acid] were prepared and structurally characterized by different techniques including elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction analysis. The X‐ray studies suggested that all these complexes except compound 2 are centrosymmetric dinuclear complexes with a tetrahedral arrangement around each zinc ion, whereas compound 2 is a mononuclear complex. The pyrazole ligand is coordinated in both terminal as well as a bridging fashion in the dinuclear moiety, whereas the pyrazole ligand in compound 2 is coordinated only in monodentate terminal fashion with its neutral nitrogen group. In all four complexes the carboxylate functions behave as monodentate ligands. All complexes show intramolecular hydrogen bonding of N–H···O between N–H of pyrazole and nonbonded oxygen atom of carboxylate. Furthermore, rich intermolecular weak interactions such as classical hydrogen bonds, C–H···O, C–H···N, C–H···π, and CH3–π interactions exist and complexes 1–4 display a set of 3D superamolecular frameworks. In addition, the four compounds are thermally stable below 150 °C.
Molecular Structure and Solution Behavior of a Benzonitrile Ligated Silver(I) Complex [Ag(PhCN)2][B(C6F5)4]
Authors: Rach Silvana F. , Herdtweck Eberhardt , Kühn Fritz E. 
Published: March 2011

AbstractThe bis(benzonitrile) complex [Ag(PhCN)2][B(C6F5)4] is synthesized from its tetra(acetonitrile) ligated congener. X‐ray diffraction studies were conducted to compare the bond lengths and angles of the complex in regard with those of other nitrile ligated silver cations with weakly coordinating anions. Vibrational spectra of the solid complex and in (concentrated) benzonitrile solution reveal differences in the strength of benzonitrile‐silver ion interactions.
Analysis of Outpatient Trauma Referrals in a Sub‐Saharan African Orthopedic Center
Authors: Jergesen Harry , Oloruntoba David , Aluede Edward , Grova Monica , Phillips Jonathan , Caldwell Amber 
Published: March 2011

AbstractBackgroundThe purpose of this study was to characterize the orthopedic trauma workload in the Bedford Orthopaedic Centre (BOC), an orthopedic referral hospital in rural South Africa.MethodsDemographic data, injury data, and information about initial management were collected for two 6‐week periods during both 2008 and 2009 from patients seen in the BOC outpatient department. Two primary outcomes were evaluated: (1) the interval between the initial outside evaluation and the BOC consultation and (2) the presence of established infection at the time of consultation. Secondary outcomes included assessments of the initial management at the referring facility.ResultsMost patients were adult men. Almost half were referred from within a radius of 10 km, but more than one‐third came from facilities in excess of 50 km away. The most frequent mode of transport was ambulance followed by taxi‐van. Fractures accounted for most of the injuries. Motor vehicle accidents and assaults were more prevalent among adults than among children, for whom falls accounted for a large proportion of injuries. Referral was delayed more than 72 h in 41.4% of patients. Established infections were indentified in 12.2%. Deficiencies detected during prehospital care were common.ConclusionThe burden of orthopedic trauma in this rural referral center is sufficient to justify the manpower and resources needed for a major orthopedic trauma center. Because most of the injuries were fractures, efforts should be aimed at improving fracture care. Differences in the mode of injury and in the anatomical sites involved between adults and children highlight the need for focused preventive measures. Reducing both delays in referral and deficiencies in initial management might well reduce the cost and complexity of the definitive treatment required.
Civilian Penetrating Axillary Artery Injuries
Authors: Gill Hardeep , Jenkins William , Edu Sorin , Bekker Wanda , Nicol Andrew J. , Navsaria Pradeep H. 
Published: March 2011

AbstractBackgroundThe surgical management and outcome of penetrating axillary artery (AA) injuries is presented.Patients and methodsPatients presenting to Groote Schuur Hospital with penetrating AA injuries from January 2003 to December 2009 were reviewed. Demographic data, mechanism of injury, associated injuries, angiographic findings, surgical treatment, complications, and mortality were noted.ResultsSixty‐eight patients with AA injuries were identified from an operating trauma database. Stab and gunshot wounds accounted for 54 (79.4%) and 14 injuries, respectively. The mean Revised Trauma Score was 7.5 (range: 3.8–7.8). Angiography was done in 49 patients; false aneurysms (32) and total occlusions (15) were the two commonest findings. Primary repair of the injured AA was possible in 41 (60.3%) patients. Five AA (7.4%) injuries were ligated. Morbidity was restricted to associated brachial plexus injuries. The limb salvage rate was 100%.ConclusionsPrimary repair of AA injuries was possible in 60% of patients, and ligation was life‐saving in critically ill patients. The associated brachial plexus injury was the cause of major long‐term morbidity.
Surgical Experience of 204 Cases of Adult Choledochal Cyst Disease over 14 Years
Authors: Cho Min‐Jeong , Hwang Shin , Lee Young‐Joo , Kim Ki‐Hun , Ahn Chul‐Soo , Moon Deok‐Bog , Lee Sung‐Koo , Kim Myung‐Hwan , Lee Sang‐Soo , Park Do‐Hyun , Lee Sung‐Gyu 
Published: March 2011

AbstractBackgroundThis study presents our 14‐year surgical experience with adult choledochal cyst disease (CCD), focusing on the clinical outcomes after surgical treatment.MethodsMedical records of 204 adult patients who had undergone surgery for CCD were reviewed retrospectively.ResultsMedian patient age was 40.2 years, and 157 (77%) of the patients were female. Todani classification was type I in 116 patients (56.9%), type II in 1 patient (0.5%), type IVa in 86 patients (42.2%), and type V in 1 patient (0.5%). Extrahepatic cyst excision and hepaticojejunostomy were performed in 185 patients (90.7%). Major perioperative complications occurred in 5 patients (2.5%), resulting in no mortality. Late complications occurred in 48 patients (23.6%). Concurrent cancer was diagnosed in 20 patients (9.8%). Mean age of patients with or without biliary cancer was 48.1 ± 13.2 years and 39.1 ± 11.8 years, respectively (P = 0.001). Anomalous union of the pancreaticobiliary duct was more frequently associated with gallbladder cancer than with bile duct cancer. De novo malignancy at the cyst remnant occurred in 2 patients (1%). The survival outcomes in CCD patients with concurrent biliary cancer were comparable to those in cancer patients without CCD.ConclusionsAs a result of diverse features of adult CCD, various clinical problems occurred after surgical excision. Surgical treatment for adult patients with CCDs having complex features should be individualized to maintain a balance between risk of surgery and potential risk of late complications.
Discrepancy between estimated and actual weight of partial liver graft from living donors
Authors: Satou Shouichi , Sugawara Yasuhiko , Tamura Sumihito , Yamashiki Noriyo , Kaneko Junichi , Aoki Taku , Hasegawa Kiyoshi , Beck Yoshifumi , Makuuchi Masatoshi , Kokudo Norihiro 
Published: March 2011

AbstractBackground/purposeA discrepancy between the actually obtained graft weight and the preoperative volumetric estimation is often observed in living donor liver transplantation. The aim of the study reported here was to clarify the prevalence and degree of this discrepancy between estimated and actual liver volume.Materials and methodsPreoperative volumetric evaluations of 26 live donor livers were performed using three‐dimensional computed tomography software. The weight of the liver graft and blood contained in the graft were measured immediately after procurement and compared with the preoperative estimate. The graft was also weighed after perfusion and after back‐table procedures.ResultsAnalysis of the results revealed that blood‐free graft weight was significantly overestimated (p = 0.02) and blood weight was significantly underestimated (p < 0.001). The sum of the weight of the graft and blood best corresponded to the preoperative volume estimate (R
2 = 0.64,p < 0.001). The back‐table procedures significantly decreased the weight of the liver graft (p < 0.001). Graft weight after perfusion and after venous reconstruction corresponded to 95 and 90% of the weight obtained before perfusion, respectively. Multivariate analysis revealed that donor age had the most significant influence on the ratio of the weight decrease in the University of Wisconsin solution (p = 0.03).ConclusionsThe weight of liver grafts decreases significantly during back‐table procedures. Underestimation of the blood weight contained in the graft is one cause of the graft weight discrepancy, but weight loss while the graft was immersed in the University of Wisconsin solution was also observed. These phenomena should be taken into account when graft size is being determined.