bluuebunny/crossref_metadata_2025_split huggingface dataset:
On curvature‐homogeneous spaces of type (1,3)
Authors: Kowalski Oldřich , Vanžurová Alena 
Published: September 2011

AbstractCurvature homogeneous spaces have been studied by many authors. In this paper, we introduce and study a natural modification of this class, namely so‐called curvature homogeneous spaces of type (1,3). We present a class of proper examples in every dimension and we prove a classification theorem in dimension 3 (for the generic case). We restrict ourselves to the Riemannian situation and to curvature homogeneity of order zero.
Homogeneous polynomials and extensions of Hardy‐Hilbert's inequality
Authors: Anagnostopoulos Vasileios A. , Sarantopoulos Yannis , Tonge Andrew M. 
Published: September 2011

AbstractIf L is a continuous symmetric n‐linear form on a real or complex Hilbert space and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\widehat{L}$\end{document} is the associated continuous n‐homogeneous polynomial, then \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Vert L\Vert =\big \Vert \widehat{L}\big \Vert$\end{document}. We give a simple proof of this well‐known result, which works for both real and complex Hilbert spaces, by using a classical inequality due to S. Bernstein for trigonometric polynomials. As an application, an open problem for the optimal lower bound of the norm of a homogeneous polynomial, which is a product of linear forms, is related to the so‐called permanent function of an n × n positive definite Hermitian matrix. We have also derived generalizations of Hardy‐Hilbert's inequality.
Fatigue behaviour of reinforcing steel under going corrosion
Authors: Gehlen C. , Weirich T. 
Published: September 2011

AbstractIn der 2001 grundlegend überarbeiteten Version der DIN 1045‐1, vgl. hierzu auch [1], ist erstmalig ein expliziter Nachweis gegen Ermüdung, d. h. ein Betriebsfestigkeitsnachweis, verankert worden. Eine Dauerschwingfestigkeit ab einer Schwingspielzahl von zwei Mio. Lastwechseln, so wie sie noch bis vor wenigen Jahren im Bauwesen üblich war, ist nicht mehr gebräuchlich. Der Einfluss von Korrosion auf das Ermüdungsverhalten wurde bisher nur unzureichend untersucht. Er kann damit als noch nicht hinreichend abgeklärt gelten. Um in diesem Bereich den Kenntnisstand zu erweitern, wurde ein Forschungsprogramm aufgelegt, in dem Dauerschwingversuche an Stahlproben u. a. mit einem Durchmesser von 16 mm unter gleichzeitig wirkender korrosiver Beanspruchung durchgeführt wurden. Insgesamt vier unterschiedliche korrosive Medien wurden überprüft. Es zeigte sich, wie erwartet, dass die Wöhler‐Linien, die sich aus den Dauerschwingversuchen ergeben, expositionsbedingt recht unterschiedliche Verläufe aufweisen. Aus werkstofftechnologischer Sicht, interessierte dazu die Fragestellung, inwieweit die Anteile der Risseinleitung‐ und Rissausbreitungsphase expositionsabhängig getrennt voneinander erfasst werden können. Diesbezüglich kamen verschiedene Prüfverfahren zur Risserkennung zum Einsatz, die sich insbesondere bezüglich ihrer Methodik unterschieden. Im Aufsatz wird der Einsatz der verwendeten Prüfmethoden zur Risserkennung kurz geschildert, die Dauerschwingversuche mit den korrosiven Medien erläutert und beschrieben, sowie deren Ergebnisse diskutiert.
Screen‐printed gold thick films for electrochemical sensor applications
Authors: Rabbow T. J. , Junker N. , Schneider M. , Michaelis A. 
Published: September 2011

AbstractScreen‐printed gold electrodes have been assembled in Low Temperature Co‐fired Ceramics technology and characterised and tested for applications in electrochemical analytics. They were investigated by scanning electron microscopy and by cyclovoltammetry in sulphuric acid and of typical redox couples such as hexacyanoferrate and quinhydrone. The electrodes differ in surface morphology, microstructure with the formation of preferential crystal orientation and exhibit different real surface sizes depending on the chosen gold paste. After pre‐treatment in sulphuric acid an almost reversible behaviour can be achieved however differences between the thick films occur at high scan rates and especially with quinhydrone. Differences in the sensitivity of the thick films at low analyte concentration can be explained by their surface properties.
Magnetic resonance analysis of capillary formation reaction front dynamics in alginate gels
Authors: Maneval James E. , Bernin Diana , Fabich Hilary T. , Seymour Joseph D. , Codd Sarah L. 
Published: September 2011

AbstractThe formation of heterogeneous structures in biopolymer gels is of current interest for biomedical applications and is of fundamental interest to understanding the molecular level origins of structures generated from disordered solutions by reactions. The cation‐mediated physical gelation of alginate by calcium and copper is analyzed using magnetic resonance measurements of spatially resolved molecular dynamics during gel front propagation. Relaxation time and pulse‐field gradient methods are applied to determine the impact of ion front motion on molecular translational dynamics. The formation of capillaries in alginate copper gels is correlated to changes in translational dynamics. Copyright © 2011 John Wiley & Sons, Ltd.
A new computational strategy for solving two‐phase flow in strongly heterogeneous poroelastic media of evolving scales
Authors: Mendes Marcos Alcoforado , Murad Marcio A. , Pereira Felipe 
Published: September 2011

SUMMARYWe develop a new computational methodology for solving two‐phase flow in highly heterogeneous porous media incorporating geomechanical coupling subject to uncertainty in the poromechanical parameters. Within the framework of a staggered‐in‐time coupling algorithm, the numerical method proposed herein relies on a Petrov–Galerkin postprocessing approach projected on the Raviart–Thomas space to compute the Darcy velocity of the mixture in conjunction with a locally conservative higher order finite volume discretization of the nonlinear transport equation for the saturation and an operator splitting procedure based on the difference in the time‐scales of transport and geomechanics to compute the effects of transient porosity upon saturation. Notable features of the numerical modeling proposed herein are the local conservation properties inherited by the discrete fluxes that are crucial to correctly capture the fingering patterns arising from the interaction between heterogeneity and nonlinear viscous coupling. Water flooding in a poroelastic formation subject to an overburden is simulated with the geology characterized by multiscale self‐similar permeability and Young modulus random fields with power‐law covariance structure. Statistical moments of the poromechanical unknowns are computed within the framework of a high‐resolution Monte Carlo method. Numerical results illustrate the necessity of adopting locally conservative schemes to obtain reliable predictions of secondary recovery and finger growth in strongly heterogeneous deformable reservoirs. Copyright © 2011 John Wiley & Sons, Ltd.
The use of botulinum toxin in benign prostatic hyperplasia
Authors: Marchal Cristobal , Perez Juan E. , Herrera Bernardo , Machuca Francisco J. , Redondo Maximino 
Published: September 2011

AbstractThe injection of Botulinum toxin type A (BoNT/A) into the prostate is a minimally invasive alternative treatment for lower urinary tract symptoms. To summarize the action mechanisms of BoNT/A on experimental animals and to analyze its effectiveness according to published clinical studies, we located 24 papers on the treatment of HBP with BoNT/A. The doses applied ranged from 100 (OnabotA) to 600 U (OnabotA and AbobotA). The IPSS score presented a mean post‐treatment reduction, for all series, of 10.8 + 2.66 points. Other significant results included the overall mean reduction in QoL score of 2.1 ± 0.62 points, and the pre and post‐treatment differences in prostate volume (22.43 ± 20.2 cm3), post‐voiding residue (76.77 + 51.72 cm3) and PSA (1.15 + 0.93 ng/ml). However, only two clinical trials were on sufficient quality to be selected for meta‐analysis, and it was observed that the difference of the means, pre‐ and post‐treatment of maximum flow, prostate volume, IPSS and PSA were not statistically significant (P = 0.18). Neither was there any statistically significant difference between pre‐ and post‐treatment post‐voiding residue (P = 0.65). In conclusion, BoNT/A alleviates lower urinary tract symptoms due to HBP, but different studies present considerable variations regarding the dose administered, inclusion criteria and follow‐up time, as well as poorly defined retreatment, losses to follow up and, above all, a high degree of variability in the communication of results (with large standard deviations). In consequence, further clinical trials are needed. Neurourol. Urodynam. 31:86–92, 2012. © 2011 Wiley Periodicals, Inc.
Fancf‐deficient mice are prone to develop ovarian tumours
Authors: Bakker Sietske T , van de Vrugt Henri J , Visser Jenny A , Delzenne‐Goette Elly , van der Wal Anja , Berns Mariska AD , van de Ven Marieke , Oostra Anneke B , de Vries Sandra , Kramer Piet , Arwert Fré , van der Valk Martin , de Winter Johan P , te Riele Hein 
Published: September 2011

AbstractFanconi anaemia (FA) is a rare recessive disorder marked by developmental abnormalities, bone marrow failure, and a high risk for the development of leukaemia and solid tumours. The inactivation of FA genes, in particular FANCF, has also been documented in sporadic tumours in non‐FA patients. To study whether there is a causal relationship between FA pathway defects and tumour development, we have generated a mouse model with a targeted disruption of the FA core complex gene Fancf. Fancf‐deficient mouse embryonic fibroblasts displayed a phenotype typical for FA cells: they showed an aberrant response to DNA cross‐linking agents as manifested by G2 arrest, chromosomal aberrations, reduced survival, and an inability to monoubiquitinate FANCD2. Fancf homozygous mice were viable, born following a normal Mendelian distribution, and showed no growth retardation or developmental abnormalities. The gonads of Fancf mutant mice functioned abnormally, showing compromised follicle development and spermatogenesis as has been observed in other FA mouse models and in FA patients. In a cohort of Fancf‐deficient mice, we observed decreased overall survival and increased tumour incidence. Notably, in seven female mice, six ovarian tumours developed: five granulosa cell tumours and one luteoma. One mouse had developed tumours in both ovaries. High‐resolution array comparative genomic hybridization (aCGH) on these tumours suggests that the increased incidence of ovarian tumours correlates with the infertility in Fancf‐deficient mice and the genomic instability characteristic of FA pathway deficiency. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Ultrasound prognostic factors after laser surgery for twin–twin transfusion syndrome to predict survival at 6 months
Authors: Ishii Keisuke , Saito Mari , Nakata Masahiko , Takahashi Yuichiro , Hayashi Satoshi , Murakoshi Takeshi , Murotsuki Jun , Kawamoto Hiroshi , Sago Haruhiko 
Published: September 2011

ObjectiveTo evaluate the significance of ultrasound findings, detected one or two weeks after laser surgery for twin–twin transfusion syndrome, in predicting the mortality at 6 months of age.MethodsUltrasound evaluation including fetal biometry, amniotic fluid volume estimation and Doppler examination was performed between 7 and 14 days after surgery for 181 cases. The presence of one or more effusions and single fetal death were also determined. Associations between ultrasound findings and mortality at 6 months of age were evaluated using multiple logistic regression analysis.ResultsOf the total 181 pairs, 145 (80.1%) donor and 160 (88.1%) recipient twins survived in utero for more than 7 days after surgery, and hence were included in the analysis. The survival rate at 6 months was 66.9% for the donor and 80.7% for the recipient twins. Risk factors for death in the donor were the presence of severe intrauterine growth restriction and effusions. In recipients, elevation in the middle cerebral artery peak systolic velocity coincided with fetal death, but this occurred in only three cases.ConclusionUltrasound risk factors one week after surgery included severe intrauterine growth restrictions and effusions in the donor twins. Copyright © 2011 John Wiley & Sons, Ltd.
Somatoform respiratory disorders in children and adolescents—proposals for a practical approach to definition and classification
Authors: Grüber Christoph , Lehmann Christine , Weiss Christa , Niggemann Bodo 
Published: September 2011

AbstractSomatoform respiratory disorders represent conditions with dysfunctional breathing unexplained by structural abnormalities. This heterogeneous group includes disorders with neural dysregulation of respiration (vocal cord dysfunction) or with dysregulation of the respiratory pattern (hyperventilation, sighing dyspnea), psychogenic disorders such as unjustified anxiety of suffocation, and stereotype conditions such as throat clearing or habit cough. Many symptoms are nonspecific and largely overlap with respiratory disease symptoms of somatic etiology. Most patients will present in a nonspecialized clinical setting. This article provides symptom‐based criteria for the definition of somatoform respiratory disorders and their differentiation from somatic disease. Emphasis is put on clinical criteria which can be easily integrated in a routine setting. Owing to the multifaceted etiology of somatoform respiratory disorders therapeutic approaches integrating somatic medicine, respiratory therapy and psychology are crucial. The introduction of defined clinical criteria may facilitate the discrimination of somatoform respiratory disorders from somatic disorders in routine patient encounters and avoid therapeutic detours. Pediatr Pulmonol. 2012; 47:199–205. © 2011 Wiley Periodicals, Inc.
Impaired behavioral and neurocognitive function in preschool children with obstructive sleep apnea
Authors: Landau Yael E. , Bar‐Yishay Orit , Greenberg‐Dotan Sari , Goldbart Aviv D. , Tarasiuk Ariel , Tal Asher 
Published: September 2011

AbstractObjectiveWe aimed to examine the hypothesis that behavioral and neurocognitive functions of preschool children with Obstructive Sleep Apnea Syndrome (OSAS) are impaired compared to healthy children, and improve after adenotonsillectomy (TA).MethodsA comprehensive assessment battery was used to assess cognitive and behavioral functions, and quality of life in children with OSAS compared to matched controls.Results45 children (mean age 45.5 ± 9 months, 73% boys, BMI 15.7 ± 2) with OSAS were compared to 26 healthy children (mean age 48.6 ± 8 months, 46% boys, BMI 16.4 ± 2). Mean AHI in the OSAS group was 13.2 ± 10.7 (ranging from 1.2 to 57). Significantly impaired planning and fluency (executive function) were found in children with OSAS, as well as impaired attention and receptive vocabulary. Parents and teachers described the OSAS group as having significantly more behavior problems. Quality of life questionnaire in children with OSAS (mean 2.3, range 0.7–4.3) was significantly worse compared to controls (mean 0, range: 0–4), P < 0.004. One year following TA, 23 children with OSAS and 18 controls were re‐evaluated. Significant improvement was documented in verbal and motor fluency, sustained attention, and vocabulary. After TA, fewer behavioral problems were seen.ConclusionsPreschool children with OSAS present significantly impaired executive functions, impaired attention and receptive vocabulary, and more behavior problems. One year after TA, the prominent improvements were in behavior and quality of life. These findings suggest that the impact of OSAS on behavioral and cognitive functions begins in early childhood. Pediatr Pulmonol. 2012; 47:180–188. © 2011 Wiley Periodicals, Inc.
Aspergilloma in a patient with an occult congenital pulmonary airway malformation
Authors: Yonker Lael M. , Mark Eugene J. , Canapari Craig A. 
Published: September 2011

AbstractWe describe the case of a 14‐year‐old male who presented with a right upper lobe aspergilloma forming in a previously occult congenital pulmonary airway malformation. This is the first case describing an aspergilloma forming within a CPAM. Pediatr Pulmonol. 2012; 47:308–310. © 2011 Wiley Periodicals, Inc.
Vascular Endothelial Growth Factor Stimulates Endothelial Colony Forming Cells Proliferation and Tubulogenesis by Inducing Oscillations in Intracellular Ca2+ Concentration
Authors: Dragoni Silvia , Laforenza Umberto , Bonetti Elisa , Lodola Francesco , Bottino Cinzia , Berra-Romani Roberto , Carlo Bongio Giacomo , Cinelli Maria Pia , Guerra Germano , Pedrazzoli Paolo , Rosti Vittorio , Tanzi Franco , Moccia Francesco 
Published: September 2011

AbstractEndothelial progenitor cells (EPCs) home from the bone marrow to the site of tissue regeneration and sustain neovascularization after acute vascular injury and upon the angiogenic switch in solid tumors. Therefore, they represent a suitable tool for cell-based therapy (CBT) in regenerative medicine and provide a novel promising target in the fight against cancer. Intracellular Ca2+ signals regulate numerous endothelial functions, such as proliferation and tubulogenesis. The growth of endothelial colony forming cells (ECFCs), which are EPCs capable of acquiring a mature endothelial phenotype, is governed by store-dependent Ca2+ entry (SOCE). This study aimed at investigating the nature and the role of VEGF-elicited Ca2+ signals in ECFCs. VEGF induced asynchronous Ca2+ oscillations, whose latency, amplitude, and frequency were correlated to the growth factor dose. Removal of external Ca2+ (0Ca2+) and SOCE inhibition with N-(4-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]phenyl)-4-methyl-1,2,3-thiadiazole-5-carboxamide (BTP-2) reduced the duration of the oscillatory signal. Blockade of phospholipase C-γ with U73122, emptying the inositol-1,4,5-trisphosphate (InsP3)-sensitive Ca2+ pools with cyclopiazonic acid (CPA), and inhibition of InsP3 receptors with 2-APB prevented the Ca2+ response to VEGF. VEGF-induced ECFC proliferation and tubulogenesis were inhibited by the Ca2+-chelant, BAPTA, and BTP-2. NF-κB activation by VEGF was impaired by BAPTA, BTP-2, and its selective blocker, thymoquinone. Thymoquinone, in turn, suppressed VEGF-dependent ECFC proliferation and tubulogenesis. These data indicate that VEGF-induced Ca2+ oscillations require the interplay between InsP3-dependent Ca2+ release and SOCE, and promote ECFC growth and tubulogenesis by engaging NF-κB. This novel signaling pathway might be exploited to enhance the outcome of CBT and chemotherapy.
Seismic behavior analysis for composite structures of steel frame‐reinforced concrete infill wall
Authors: Peng Xiaotong , Gu Qiang 
Published: September 2011

SUMMARYThe composite structure of steel frame–reinforced concrete infill wall (CSRC) combines the advantages of steel frames and reinforced concrete shear walls. Reinforced concrete infill walls increase the lateral stiffness of steel frames and reduce seismic demands on steel frames thus providing opportunities to use partially restrained connections. In order to study seismic behavior and load transfer mechanism of CSRC, a two‐story one‐bay specimen was tested under cyclic loads. With that, the main characters such as, strength, stiffness, ductility, energy dissipation, load distribution, performance of steel frames, partially restrained connections and studs, are analyzed and evaluated. The experimental results show that the structure has adequate strength redundancy and sufficient lateral stiffness. The CSRC system has good ductility and energy dissipation capability. Partially restrained connections could enhance ductility and avoid abrupt decreases in strength and stiffness after the failure of infill walls. The composite interaction is ensured by headed studs, which have failed because of low‐cycle fatigue. Steel frames bear 80%–100% of overturning moments, and the remainder is undertaken by infill walls; steel frames and infill walls resisted 10%–20% and 80%–90% of lateral loads, respectively. Furthermore, relevant design recommendations are presented. Copyright © 2011 John Wiley & Sons, Ltd.
π‐conjugated molecules covered by permethylated cyclodextrins
Authors: Terao Jun 
Published: September 2011

AbstractInsulated π‐conjugated molecules, in which the π‐conjugated compounds are covered by a cyclic protective sheath, have attracted considerable attention because of their potential applicability in next‐generation mono‐molecular electronic devices. We have developed new methods of synthesizing insulated π‐conjugated molecules involving the self‐inclusion of rotaxane precursors linking π‐conjugated units as a guest and permethylated cyclodextrin (PMCD) as a macrocyclic host. The insulated π‐conjugated molecules thus formed are highly soluble in organic solvents and display photoluminescence efficiency. This paper also highlights a new method for synthesizing insulated molecular wire (IMW) through the polymerization of insulated π‐conjugated molecules as monomers. The IMWs thus formed have a high covering ratio, rigidity, and showed high charge mobility in the solid state; further, they are readily soluble in a variety of organic solvents. In this account, the synthetic methodologies and characteristic of insulated π‐conjugated molecules and IMWs are discussed. DOI 10.1002/tcr.201100009
The missing disciplinary substance of formative assessment
Authors: Coffey Janet E. , Hammer David , Levin Daniel M. , Grant Terrance 
Published: September 2011

AbstractWe raise concerns about the current state of research and development in formative assessment, specifically to argue that in its concentration on strategies for the teacher, the literature overlooks the disciplinary substance of what teachers and students assess. Our argument requires analysis of specific instances in the literature, and so we have selected four prominent publications for consideration as examples. These, we show, pay little attention to the student reasoning they depict, presume traditional notions of “content” as correct information, and treat assessment as distinct from other activities of learning and teaching, even when they claim the contrary. We then offer an alternative image of formative assessment centered on attention to disciplinary substance, which we illustrate with an example from a high school biology class. Assessment, we contend, should be understood and presented as genuine engagement with ideas, continuous with the disciplinary practices science teaching should be working to cultivate. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 48: 1109–1136, 2011
Bootstrap
Authors: Hesterberg Tim 
Published: September 2011

AbstractThis article provides an introduction to the bootstrap. The bootstrap provides statistical inferences—standard error and bias estimates, confidence intervals, and hypothesis tests—without assumptions such as Normal distributions or equal variances. As such, bootstrap methods can be remarkably more accurate than classical inferences based on Normal or t distributions. The bootstrap uses the same basic procedure regardless of the statistic being calculated, without requiring the use of application‐specific formulae. This article may provide two big surprises for many readers. The first is that the bootstrap shows that common t confidence intervals are woefully inaccurate when populations are skewed, with one‐sided coverage levels off by factors of two or more, even for very large samples. The second is that the number of bootstrap samples required is much larger than generally realized. WIREs Comp Stat 2011 3 497–526 DOI: 10.1002/wics.182This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Bootstrap and Resampling