bluuebunny/crossref_metadata_2025 huggingface dataset:
Nasal reconstruction
Authors: Michelotti B. , Mackay D.
Published: October 2011

The nose is the central feature that defines one's face. Acquired nasal defects arise from a variety of pathologic and traumatic etiologies and reconstructive surgeons may be called upon to restore form and function when the nose has been altered in some way. Nasal reconstruction is one of the most challenging and rewarding procedures performed by the plastic surgeon. A detailed knowledge of the anatomy of the nose – the lining, support and cover – is essential in designing the reconstructive effort. Surgical planning involves, first, identifying the extent of the acquired defect, followed by the application of an intricate knowledge of the tissues that will provide a functional and aesthetically pleasing yet durable reconstruction. In this article, the reader will find a description of the clinically important anatomic features of the nose as they relate to various reconstructive procedures aimed at restoring nasal appearance and maintaining airway patency. Clin. Anat. 25:86–98, 2012. © 2011 Wiley Periodicals, Inc.
Sparsomycin–Linezolid Conjugates Can Promote Ribosomal Translocation
Authors: Li Shibo , Cheng Xiaofeng , Zhou Yonghang , Xi Zhen
Published: October 2011

Sparsomycin is an antibiotic that targets the peptidyl transferase center of the ribosome and has the ability to promote ribosomal translocation in the absence of EF‐G and GTP. Here we show that changes in the configurations at the two chiral centers of sparsomycin, especially at the chiral carbon, can greatly affect its capability to promote ribosomal translocation. More importantly, the incorporation of the pseudo‐uracil moiety of sparsomycin into linezolid through a covalent linkage conferred on linezolid derivatives the ability to promote translocation, thus indicating the importance of interactions between this pseudo‐uracil moiety, rRNA, and tRNA for promoting translocation. In addition, these translocation promoters can also effectively inhibit spontaneous reverse translocation; this suggests that they might promote forward translocation by trapping the ribosome in the post‐translocation state and shifting the equilibrium between the pre‐ and post‐translocation ribosome in the forward direction.
Sequential Centrifugal Partition Chromatography: A New Continuous Chromatographic Technology
Authors: Hopmann E. , Goll J. , Minceva M.
Published: October 2011

In solid‐support‐free liquid‐liquid chromatography, both phases can be used as a mobile phase and, moreover, their role and flow direction can be reversed during the course of the separation. This is the background of the concept of sequential centrifugal partition chromatography (sCPC) developed to perform a continuous separation in a cyclic manner. The feed is continuously introduced between two centrifugal partition chromatographic columns and two products are alternately collected at the opposite ends of the columns. In this work, a method is presented to select the operating parameters of an sCPC unit for the complete separation of a binary feed mixture. The method uses, as a basis, a restricted number of experiments needed to determine the distribution equilibrium of the components to be separated and to evaluate the column hydrodynamics. The method was validated experimentally for the separation of a binary mixture of hydroquinone and pyrocatechol.
Evaluation of the Benefit of Cold Flow Experiments for the Characterization of Column Internals
Authors: Mudimu Ompe Aime , Markus Matthias , Ruffert Gerhard
Published: October 2011

Cold‐Flow‐Experimente mit Luft und Wasser als Modellfluide können einen wichtigen Beitrag zur Charakterisierung von Kolonneneinbauten leisten. Sie sind mit vergleichsweise niedrigem Aufwand durchführbar, dienen andererseits aber als unerlässliche Stützpunkte für fluiddynamische Modellansätze, die wiederum die Brücke zu technisch relevanten Stoffsystemen und Betriebsbedingungen darstellen. Durch Kombination mit anderen Bewertungsmethoden, wie z. B. Testgemisch‐Untersuchungen oder mathematischen Modellen, können sie sehr wichtige Informationen zur sicheren und zielgenauen Auslegung von Kolonneneinbauten liefern. Es werden die Möglichkeiten, aber auch die Grenzen von Cold‐Flow‐Experimenten beleuchtet und in Beziehung zu Versuchen mit organischen Systemen gesetzt.
Proton‐Conducting Composite Membranes for Future Perspective Applications in Fuel Cells, Desalination Facilities and Photocatalysis
Authors: Marschall Roland , Sharifi Monir , Wark Michael
Published: October 2011

Anorganische Füllmaterialien dienen oft der Verbesserung der mechanischen, thermischen und chemischen Eigenschaften von Polymermembranen. Im Falle protonenleitender Polymere ist es dabei allerdings gleichzeitig nötig, die Protonenleitung der Matrix zu unterstützen bzw. wenigstens nicht zu stören. Durch geeignete Kombinationen aus Polymer und Füllermaterial können so effektive und sehr gut leitfähige Komposit‐Membranen hergestellt werden. Dieser Artikel gibt einen Überblick über die möglichen Anwendungen einer speziellen protonenleitenden Komposit‐Membran, die funktionalisierte SiO2‐Partikel mit geordneter Mesoporosität enthält, in Brennstoffzellen, zur Entsalzung von Wasser und in der Photokatalyse.
Guest Diffusion in Binderless High‐Performance NaX Molecular Sieves
Authors: Mehlhorn Dirk , Valiullin Rustem , Kärger Jörg , Schumann Kristin , Brandt Alfons , Unger Baldur
Published: October 2011

The pulsed field gradient (PFG) NMR technique is applied for exploring the diffusion behavior of guest molecules in binderless NaX beads in comparison with the zeolite powder employed for their production. With both probe molecules applied (water, n‐hexane), the diffusivities in the powder and the beads are found to essentially coincide as long as the diffusion path lengths are sufficiently small in comparison with the extension of the individual particles (crystallites) of the powder. With increasing diffusion path lengths, characteristic deviations become observable that can be attributed to the differences in long‐range mass transfer through the intercrystalline void volume of the bed of crystallites and within the individual beads of the binderless molecular sieve, respectively. With these studies, PFG NMR demonstrates its potentials for simultaneously recording mass transfer phenomena in both the micro‐ and macropores of commercially produced binderless molecular sieves.
A chemical oscillating reaction in NaBrO3‐pyruvic acid‐H2SP4‐‐[Ni(Me2[14]1,3‐diene N4)]2+ system
Authors: Zhao Liang , Xu Zhi‐Qiang , Wu Chang‐Chun , Xie Fu‐Xin , Ni Shi‐Sheng , Luo Yi
Published: October 2011

In this paper we report a chemical oscillation catalyzed by [Ni(Me2[14]l,3‐diene N4)]2+ (Me2[14]1,3‐diene N4 denotes 2,3‐dimethyl‐1,4,8,11‐tetraazacyclotetradeca‐1,3‐diene) in BrO3‐pyruvic acid‐H2SO4 system. The domain of the existence of the oscillation waa obtained. The effect of initial concentration of the components on the oscillation were studied. The features of the oscillations were described in detail. We also examined the effects of Ag+, Hg2+, CCl4, free radical inhibitors, etc. on the oscillations.
Ac voltammetric and square wave voltammetric study of the self‐assembled monolayers of thiol‐functionalized viologen derivative
Authors: Li Jing‐Hong , Yang Chun‐He , Yan Ju‐Chao , Chen Wen‐Qi , Dong Shao‐Jun
Published: October 2011

Electroactive self‐assembled monolayers (SAMs) containing viologen group are formed through the adsorption of thiol‐functionalized viologen compound CH3(CH2)9V2+(CH2)8SH, where V2+ is N,N'‐dialkylbipyridinium (i.e. a viologen group), onto gold electrodes form methanol/water solution and its electrochemical behavior is investigated by Ac voltammetry and square wave voltammetry, which have the high sensitivity against background charging. The viologen SAM formed is a sub‐monolayer and the normal potentials corresponding to the two successive oneelectron transfer processes of the active centers (viologen) are ‐360 mV and ‐750 mV (vs. Ag/AgCl) in 0.1 mol/L phosphate buffer solutions (pH 6.96) respectively, and the standard electron transfer rate constant is 9.0 s−1. The electrochemical behavior of this SAM in various solutions has been preliminarily discussed.
Studies on the energy transfer system of terbium‐norfloxacin chelate and its interaction with serum albumins
Authors: Xu Yan , Shen Han‐Xi , Huang Han‐Guo
Published: October 2011

The energy absorbed by norfloxacin could be transferred to terbium(III) through chelation of norfloxacin with terbium(III), then the characteristic fluorescence emission could be observed. The interaction of serum albumins with norfloxacin have been investigated in this paper. The results showed that HSA could inhibit the energy transfer between norfloxacin and terbium(III). But, BSA could not. It was shown that the binding properties of norfloxacin to HSA and BSA were totally different.
Effect of organic modifiers on the capacity factor in micellar electrokinetic chromatography
Authors: Shi Wei , Zhang Jin , Wang Lei , Zou Han‐Fa , Zhang Yu‐Kui
Published: October 2011

Organic modifiers were effective both to extend the migration time window and to improve the separation of very hydrophobic compounds in MEKC. An iteration method was wed to determine the migration time of micelles. The quantitative relationship between the capacity factor k' and the concentration of organic modifiers was derived, which wan investigated experimentally. The linear solvation energy relationship (LSER) methodology was applied to MEKC, and good linear relationships between Ink' and solvatochromic parameters of 15 solutes were obtained in the presence of organic modifier in different concentrations, which indicated a new access in MEKC to predict k' from the structural parameters of solutes. The effect of column temperature T on k' was also investigated.
Photochemistry of nonconjugated bichromophoric systems III. Synthesis and photoreaction of poly(ethylene glycol) biscoumarinyloxyacetates
Authors: Wang Yong‐Mei , Du Da‐Ming , Meng Ji‐Ben , Zhou Xiu‐Zhong , Wang Lei
Published: October 2011

A series of poly(ethylene glycol) biscoumarinyloxyacetatea have been synthesized and their intramolecular photochemical cyclodimerizations have been studied. It was found that only syn‐HT configuration products were obtained when these bisesters were directly irradiated in chloroform, and the yields of the products decreased with the increase of the chain length. This photocyclization reaction is a convenient and effective method to synthesize macrocyclic compounds.
A new strategy for the stereospecific syntheses of C‐furanosides
Authors: Yang Bing‐Hui , Jiang Ji‐Qing , Huang Xi‐Lin , Wu Hou‐Ming
Published: October 2011

This reaction provided an efficient method to synthesize C‐furanoside derivatives in high yields and stereospecificity under mild conditions. The cyclization mechanism regarding benzyl group as a leaving group was discussed and their stereochemistry waa deduced by 1H‐1H NOESY data.
BIOREGIS Software Platform Based on GIS Technology to Support in‐Situ Remediation of Petroleum Contaminated Sites. Case Study: Razvad – Dambovita County, Romania
Authors: Anicai Ovidiu , Anicai Liana
Published: October 2011

With a need for the management of petroleum contaminated sites on Romanian territory, an experimental software platform involving ESRI‐ArcGIS technologies (BIOREGIS) is presented in this study. The BIOREGIS platform is aimed to: (i) Build the structure of relational, standardized databases to store spatial and textual characteristic information on polluted sites for further risk analysis and planning of remediation actions, (ii) improve the pollution risk assessment methodology for Romanian petroleum contaminated sites and its informatics implementation, and (iii) develop and operate the software platform for pollution risk based management involving GIS/remote sensing technologies and remediation activities. The operation of BIOREGIS has been tested for a pilot contaminated area situated at Razvad – Dambovita County, which has been subjected to in situ remediation procedures involving both bioremediation and electrokinetic processes.
Patterns of care and treatment outcomes for elderly women with cervical cancer
Authors: Sharma Charu , Deutsch Israel , Horowitz David P. , Hershman Dawn L. , Lewin Sharyn N. , Lu Yu‐Shiang , Neugut Alfred I. , Herzog Thomas J. , Chao Clifford K. , Wright Jason D.
Published: October 2011

BACKGROUND:

Cervical cancer is common in the elderly. The authors examined the patterns of care, treatment, and outcomes of elderly women with cervical cancer.

METHODS:

Women with cervical cancer diagnosed between 1988 and 2005 and registered in the Surveillance, Epidemiology, and End Results database were analyzed. Patients were stratified by age: <50, 50 to 59, 60 to 69, 70 to 79, and ≥80 years. Multivariate logistic regression models were constructed to examine treatment; cancer‐specific survival was examined using Cox proportional hazards models.

RESULTS:

A total of 28,902 women were identified, including 2543 women 70 to 79 years old and 1364 ≥80 years. For women with early stage (IB1‐IIA) tumors, primary surgery was performed in 82.0% of women <50 years old compared with 54.5% of those 70 to 79 years old and 33.2% of those ≥80 years old (P < .0001). For women treated surgically, lymphadenectomy was performed in 66.8% of women <50 years old versus 9.1% of patients ≥80 years old (P < .0001). Compared with patients <50 years old, those >80 years old were less likely to undergo radical hysterectomy (odds ratio [OR], 0.10; 95% confidence interval [CI], 0.07‐0.14) and lymphadenectomy (OR, 0.11; 95% CI, 0.08‐0.16) and to receive adjuvant radiation therapy (OR, 0.06; 95% CI, 0.01‐0.35). Among women with stage IIB‐IVA disease, use of brachytherapy declined with age (P < .0001). For women with stage IB1‐IIA tumors, the hazard ratio for death from cancer was 1.35 (95% CI, 1.16‐1.58) for women 70 to 79 years old and 2.08 (95% CI, 1.72‐2.48) for those ≥80 years old compared with younger women.

CONCLUSIONS:

Elderly women with cervical cancer are less likely to undergo surgery, receive adjuvant radiation, and receive brachytherapy. After adjusting for treatment disparities, cancer‐specific mortality is higher in older women. Cancer 2012;3618–3626. © 2011 American Cancer Society.
Magnetic Resonance and Mössbauer Studies of Superparamagnetic γ‐Fe2O3 Nanoparticles Encapsulated into Liquid‐Crystalline Poly(propylene imine) Dendrimers
Authors: Domracheva Natalia E. , Pyataev Andrew V. , Manapov Rafil A. , Gruzdev Matvey S.
Published: October 2011

We present the first results of electron magnetic resonance (EMR) and Mössbauer spectroscopy studies of γ‐Fe2O3 nanoparticles (NPs) incorporated into liquid‐crystalline, second‐generation dendrimers. The mean size of NPs formed in the dendrimers was around 2.5 nm. A temperature‐driven transition from superparamagnetic to ferrimagnetic resonance was observed for the sample. Low‐temperature blocking of the NP magnetic moments has been clearly evidenced in the integrated EMR line intensity and the blocking temperature was about 60 K. The physical parameters of magnetic NPs (magnetic moment, effective magnetic anisotropy) have been determined from analyses of the EMR data. The effective magnetic anisotropy constant is enhanced relative to bulk γ‐Fe2O3 and this enhanced value is associated with the influence of the surface and shape effects. The angular dependence of the EMR signal position for the field‐freezing sample from liquid‐crystalline phase showed that NPs possessed uniaxial anisotropy, in contrast to bulk γ‐Fe2O3. Mössbauer spectroscopy determined that fabricated NPs consisted of an α‐Fe core and a γ‐Fe2O3 shell.
The Role of the π Linker in Donor–π–Acceptor Organic Dyes for High‐Performance Sensitized Solar Cells
Authors: Casanova David
Published: October 2011

The key elements arising from different linkers between donor (D) and acceptor (A) fragments in D–π–A organic dyes are computationally studied. Taking triarylamine and the cyanoacrylic acid fragments as donor and acceptor units, respectively, the role of the different separators is computationally explored by means of optimized geometries, frontier molecular orbitals, static polarizabilities and hyperpolarizabilities, excitation energies to the lowest excited singlet, the charge‐transfer character of the transition, and simulated absorption spectra. The results are compared to two closely related sets of linkers. Electronic‐structure calculations on the studied organic dyes are performed with the CIS(D) wave function based method and time‐dependent density functional theory (ωB97, ωB97X, and ωPBEh functionals). Solvation effects are introduced with the polarizable continuum model (PCM).
Primer and interviews: Advances in targeted gene modification
Authors: Kiefer Julie C.
Published: October 2011

Gene targeting in mice, first reported 25 years ago, has led to monumental advances in the understanding of basic biology and human disease. The ability to employ a similarly straightforward method for gene manipulation in other experimental organisms would make their already significant contributions all the more powerful. Here, we briefly outline the strengths and weaknesses of reverse genetics techniques in non‐murine model organisms, ending with a more detailed description of two that promise to bring targeted gene modification to the masses: zinc finger nucleases (ZFNs) and transcription activator‐like effector nucleases (TALENs). Dana Caroll, a forefather of zinc finger technology, and Bo Zhang, among the first to introduce TALEN‐targeted mutagenesis to zebrafish, discuss their experience with these techniques, and speculate about the future of the field. Developmental Dynamics 240:2688–2696, 2011. © 2011 Wiley Periodicals, Inc.
Why men should be included in research on binge eating: Results from a comparison of psychosocial impairment in men and women
Authors: Striegel Ruth H. , Bedrosian Richard , Wang Chun , Schwartz Steven
Published: October 2011

Objective:

Prevalence of binge eating has been shown to be as common in men as in women, yet few studies have included men. Men are especially underrepresented in treatment studies, raising the question of whether men who binge eat experience less distress or impairment than women. This study compared demographic and clinical correlates of binge eating in a large employee sample of men and women.

Method:

Cross‐sectional data from 21,743 men and 24,608 women who participated in a health risk self assessment screening were used. Group differences in obesity, hypertension, dyslipidemia, Type 2 diabetes, depression, stress, sleep, sick days, work impairment, and nonwork activity impairment were tested using chi‐square tests (categorical variables) and independent sample t‐tests (continuous variables).

Results:

Effect size estimates indicate that men (n = 1,630) and women (n = 2,754) who binge eat experience comparable levels of clinical impairment. They also report substantially greater impairment when compared with men and women who do not binge eat.

Discussion:

The underrepresentation of men in treatment‐seeking samples does not appear to reflect lower levels of impairment in men versus women. Efforts are needed to raise awareness of the clinical significance of binge eating in men so that this group can receive appropriate screening and treatment services. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012)
Structural Relationship between Calcite–Gelatine Composites and Biogenic (Human) Otoconia
Authors: Simon Paul , Carrillo‐Cabrera Wilder , Huang Ya‐Xi , Buder Jana , Borrmann Horst , Cardoso‐Gil Raul , Rosseeva Elena , Yarin Yuri , Zahnert Thomas , Kniep Rüdiger
Published: October 2011

Biogenic otoconia (ear dust) are composite materials of calcite with about 2 wt.‐% proteins showing an average longitudinal size of about 10 μm. The tiny biomineral particles are situated in the inner ear (in the maculae) and act as sensors for gravity and linear acceleration. Our comparative study of calcite–gelatine composites (grown by double diffusion) and human otoconia is based on decalcification experiments, scanning electron microscopy, TEM and X‐ray investigations in order to obtain a complete picture of the 3D structure and morphogenesis of the materials. Otoconia as calcite–protein composites display a cylindrical body with terminal rhombohedral faces intersecting at the pointed ends. As evidenced by TEM on focused ion beam cuts, both the artificial composites and human otoconia show a particular distribution of areas with different volume densities leading to a dumbbell‐shape of the more dense parts consisting of rhombohedral branches (with end faces) and a less ordered, less dense area (the belly region). The peculiar inner architecture of otoconia with its dumbbell‐shaped mass/density distribution is assumed to be necessary for optimal sensing of linear accelerations.
Oscillating Non‐Metallocenes – from Stereoblock‐Isotactic Polypropylene to Isotactic Polypropylene via Zirconium and Hafnium Dithiodiphenolate Catalysts
Authors: Cohen Ad , Goldberg Israel , Venditto Vincenzo , Kol Moshe
Published: October 2011

Octahedral group 4 complexes of a new bulky tetradentate dithiodiphenolate {OSSO}‐type ligand that oscillate between two enantiomeric C2‐symmetric conformations are described. The dibenzyl Zr and Hf complexes led to active catalysts in propylene polymerization. Polypropylene having predominantly stereoblock‐isotactic microstructure or predominantly isotactic microstructure could be obtained by varying the polymerization conditions. Long isotactic blocks of 50 to more than 100 repeat units were formed at –10 °C in liquid propylene.
Reduction of Aromatic and Aliphatic Esters Using the Reducing Systems MoO2(acac)2 or V(O)(OiPr)3 in Combination with 1,1,3,3‐Tetramethyldisiloxane
Authors: Pehlivan Leyla , Métay Estelle , Laval Stéphane , Dayoub Wissam , Delbrayelle Dominique , Mignani Gérard , Lemaire Marc
Published: October 2011

An efficient reduction of aromatic and aliphatic esters with 1,1,3,3‐tetramethyldisiloxane in combination with [MoO2(acac)2] or [V(O)(OiPr)3] is reported. In the former system, the presence of triphenylphosphane oxide allows high conversion and good isolated yield to be reached. For the latter system, no ligand is necessary to obtain the corresponding alcohols with similar results.
Synthesis and Biological Evaluation of Gephyronic Acid Derivatives: Initial Steps towards the Identification of the Biological Target of Polyketide Inhibitors of Eukaryotic Protein Synthesis
Authors: Anderl Timo , Nicolas Lionel , Münkemer Johanna , Muthukumar Yazh , Baro Angelika , Frey Wolfgang , Sasse Florenz , Taylor Richard E. , Laschat Sabine
Published: October 2011

Coupled to the development of a total synthesis of gephyronic acid, a series of diastereomeric analogues and their precursors have been prepared by employing complementary aldol strategies for the key coupling step of fragments 4 and 5. A biological evaluation revealed the importance of the epoxide for the cytotoxicity against L‐929 (mouse fibroblast) and KB‐3‐1 (HeLa clone, human cervix carcinoma derived) cell lines. Moreover, variation of the configuration of the C3–C5 stereotriad and the C1 carboxylic acid were found to be important features. Improved activities compared with the natural product were observed when the carboxy terminus at C1 was replaced by a methyl ester or PMB‐protected alcohol. Surprisingly, the derivatives (8R)‐17d and (8S)‐16a showed antibacterial activity against Pseudomonas aeruginosa.
An opportunity to connect the morphodynamics of alternate bars with their sedimentary products
Authors: Rodrigues Stephane , Claude Nicolas , Juge Philippe , Breheret Jean‐Gabriel
Published: October 2011

Field investigations that help clarify local sedimentary processes involved in the migration of alternate bars as a consequence of flood events are lacking. A simple approach combining scour chains, stratigraphy and frequent bathymetric surveys is proposed to connect the dynamics of free migrating alternate bars present in disconnected channels of large sandy‐gravelly rivers with their sedimentary products and vice versa. The results show that the spatial distribution of bars before a flood partly governs the scour and fill processes and that the sediment transport rates vary significantly on a single cross‐section. This can be due to preferential axes of the migration of the bars determined by their location on the cross‐section, the bank direction and the discharge. The approach allows the reconstruction of local sedimentary processes involved in alternate bar migration by combining maximum scour depths reached during a flood with frequent channel bed topography surveys and post‐flood stratigraphy. It is also possible to distinguish deposited and preserved sediments compared with sediments by‐passed during the flood. Copyright © 2011 John Wiley & Sons, Ltd.
Uplink OFDMA resource allocation with discrete rates: optimal solution and suboptimal implementation
Authors: Yaacoub Elias , El‐Hajj Ahmad M. , Dawy Zaher
Published: October 2011

Resource allocation in the uplink of orthogonal frequency‐division multiple access systems is investigated. The problem of ergodic utility maximisation with discrete rates is formulated and solved using dual Lagrangian techniques. Suboptimal algorithms based on equal power allocation over the subcarriers are proposed. Results are presented and compared for the continuous and discrete rates scenario, using both the optimal solutions and the suboptimal algorithms. Equal power allocation is shown to approximate well the optimal solution in the continuous rates case, as well as in the discrete rates scenario when the number of modulation and coding schemes increases. Copyright © 2011 John Wiley & Sons, Ltd.
Sensing of OFDM signals with cyclic delay diversity over doubly‐selective fading channels
Authors: Tian Jinfeng , Jiang Yonglei , Chen Huaxia , Hu Honglin
Published: October 2011

Orthogonal frequency division multiplexing signals with cyclic delay diversity (CDD) exhibit distinguishable cyclostationarity that can be used to design cyclostationary signatures for cognitive radio networks. However, such cyclostationary signatures are seriously weakened over doubly‐selective fading channels, which consequently causes remarkable performance degradation of cyclostationarity‐based detectors. In this paper, we propose a new detector for CDD orthogonal frequency division multiplexing (CDD‐OFDM) signals over doubly‐selective fading channels. By modelling the doubly‐selective fading channel with basis expansion model, we derive the second‐order cyclic statistics of the received CDD‐OFDM signal in close form. Not only the transmitter‐induced cyclostationary characteristics but also the channel‐spread cyclostationary features are exploited for sensing CDD‐OFDM signals that experience doubly‐selective fading. Simulation results indicate that the proposed detector provides substantial performance improvement. Copyright © 2011 John Wiley & Sons, Ltd.
Using CAViaR Models with Implied Volatility for Value‐at‐Risk Estimation
Authors: Jeon Jooyoung , Taylor James W.
Published: October 2011

This paper proposes value‐at risk (VaR) estimation methods that are a synthesis of conditional autoregressive value at risk (CAViaR) time series models and implied volatility. The appeal of this proposal is that it merges information from the historical time series and the different information supplied by the market's expectation of risk. Forecast‐combining methods, with weights estimated using quantile regression, are considered. We also investigate plugging implied volatility into the CAViaR models—a procedure that has not been considered in the VaR area so far. Results for daily index returns indicate that the newly proposed methods are comparable or superior to individual methods, such as the standard CAViaR models and quantiles constructed from implied volatility and the empirical distribution of standardised residuals. We find that the implied volatility has more explanatory power as the focus moves further out into the left tail of the conditional distribution of S&P 500 daily returns. Copyright © 2012 John Wiley & Sons, Ltd.
Claudin-1 involved in neonatal ichthyosis sclerosing cholangitis syndrome regulates hepatic paracellular permeability
Authors: Grosse Brigitte , Cassio Doris , Yousef Nadya , Bernardo Céline , Jacquemin Emmanuel , Gonzales Emmanuel
Published: October 2011

Neonatal ichthyosis and sclerosing cholangitis (NISCH) syndrome is a liver disease caused by mutations of CLDN1 encoding Claudin-1, a tight-junction (TJ) protein. In this syndrome, it is speculated that cholestasis is caused by Claudin-1 absence, leading to increased paracellular permeability and liver injuries secondary to paracellular bile regurgitation. We studied the role of claudin-1 in hepatic paracellular permeability. A NISCH liver and polarized rat cell lines forming TJs, the hepatocellular Can 10 and the cholangiocellular normal rat choloangiocyte (NRC), were used. In contrast to NRC, Can 10 does not express claudin-1. Can 10 cells were transfected with a plasmid encoding Claudin-1, and stable Claudin-1-expressing clones were isolated. Claudin-1 expression was silenced by transfection with short interfering RNA in Can 10 clones and with short hairpin RNA in NRC. Claudin-1 expression was evaluated by quantitative reverse-transcriptase polymerase chain reaction, immunoblotting, and immunolocalization. Paracellular permeability was assessed by fluorescein isothiocyanate-dextran passage in both lines and by transepithelial resistance measurements in NRC. In the NISCH liver, Claudin-1 was not detected in hepatocytes or cholangiocytes. In Claudin-1 expressing Can 10 clones, Claudin-1 was localized at the TJ and paracellular permeability was decreased, compared to parental Can 10 cells, this decrease correlating with claudin-1 levels. Silencing of Claudin-1 in Can 10 clones increased paracellular permeability to a level similar to that of parental cells. Similarly, we observed an increase of paracellular permeability in NRC cells silenced for claudin-1 expression. Conclusion: Defect in claudin-1 expression increases paracellular permeability in polarized hepatic cell lines, supporting the hypothesis that paracellular bile leakage through deficient TJs is involved in liver pathology observed in NISCH syndrome. (Hepatology 2012)
Probabilistic evaluation of flood hazard in urban areas using Monte Carlo simulation
Authors: Aronica G. T. , Franza F. , Bates P. D. , Neal J. C.
Published: October 2011

The goal of the presented research was the derivation of flood hazard maps, using Monte Carlo simulation of flood propagation at an urban site in the UK, specifically an urban area of the city of Glasgow. A hydrodynamic model describing the propagation of flood waves, based on the De Saint Venant equations in two‐dimensional form capable of accounting for the topographic complexity of the area (preferential outflow paths, buildings, manholes, etc.) and for the characteristics of prevailing imperviousness typical of the urban areas, has been used to derive the hydrodynamic characteristics of flood events (i.e. water depths and flow velocities). The knowledge of the water depth distribution and of the current velocities derived from the propagation model along with the knowledge of the topographic characteristics of the urban area from digital map data allowed for the production of hazard maps based on properly defined hazard indexes. These indexes are evaluated in a probabilistic framework to overcome the classical problem of single deterministic prediction of flood extent for the design event and to introduce the concept of the likelihood of flooding at a given point as the sum of data uncertainty, model structural error and parameterization uncertainty. Copyright © 2011 John Wiley & Sons, Ltd.
Water balance of irrigated areas: a remote sensing approach
Authors: Taghvaeian Saleh , Neale Christopher M.U.
Published: October 2011

An efficient management of our precious water resources is not possible without acquiring a comprehensive and detailed understanding on water fluxes at irrigated areas. In the past few decades, agricultural water balance analyses have been carried out at a wide variety of temporal (from hourly to annual) and spatial (from plant root zone to basin) scales. Scheme‐wide water balance analyses, in particular, provide information on the amount of water supplied to irrigation schemes and its fate. This paper attempts to summarise the results of previous studies in quantifying water balance components of irrigation schemes, as well as to present challenges and opportunities of conducting such research projects. With recent improvements in air‐ and space‐borne imaging of land surfaces, remote sensing techniques nowadays can serve as a powerful tool in monitoring/modeling water movements, at or near real time. Remote sensing contribution to water balance studies could be as simple as developing crop classification maps, or as complicated as estimating the spatially distributed evapotranspiration, which is perhaps the most critical water flux in irrigated areas. Therefore, this paper also aims to review the few studies that have incorporated satellite‐derived products in their water budget analysis. Finally, the results of a case study from the southern California are presented to better demonstrate the potential of remotely sensed data. Copyright © 2011 John Wiley & Sons, Ltd.
EVAPORATION AND WIND DRIFT LOSSES DURING SPRINKLER IRRIGATION INFLUENCED BY DROPLET SIZE DISTRIBUTION
Authors: Molle B. , Tomas S. , Hendawi M. , Granier J.
Published: October 2011

Irrigated agriculture is often criticized for its poor resource‐use efficiency in the case of sprinkler systems in comparison with localized irrigation. Water losses due to evaporation of droplets during flight and wind drift of droplets out of the target area are often generalized regardless of the context in which they were measured, and may reveal the evaporation capacity of the measurement facility rather than that of the irrigation system itself. Using an approach combining in situ measurement (rainfall, electric conductivity) and simulations, losses were estimated according to droplet size distribution. Droplets less than 1 mm in diameter displayed the highest losses. Losses due to evaporation represented 30‐50% of total loss; the remaining 50–70% were due to wind causing small droplets to drift outside the target zone. With a Rain Bird 46 sprinkler, total losses for the different periods of the day should not represent more than 20% at any time, or less than 4% for a 24‐h irrigation period in the climate conditions that prevail in summer in the south of France. Copyright © 2011 John Wiley & Sons, Ltd.
VAR FORECASTING USING BAYESIAN VARIABLE SELECTION
Authors: Korobilis Dimitris
Published: October 2011

This paper develops methods for automatic selection of variables in Bayesian vector autoregressions (VARs) using the Gibbs sampler. In particular, I provide computationally efficient algorithms for stochastic variable selection in generic linear and nonlinear models, as well as models of large dimensions. The performance of the proposed variable selection method is assessed in forecasting three major macroeconomic time series of the UK economy. Data‐based restrictions of VAR coefficients can help improve upon their unrestricted counterparts in forecasting, and in many cases they compare favorably to shrinkage estimators. Copyright © 2011 John Wiley & Sons, Ltd.
TAX‐LIMITED REACTION FUNCTIONS
Authors: Porto Edoardo Di , Revelli Federico
Published: October 2011

This paper models for the first time a spatial process in local tax policies in the presence of centrally imposed fiscal limitations. Focusing on the frequently encountered case of a tax rate cap, we evaluate three empirical approaches to the analysis of spatially dependent limited tax policies: (i) a Bayesian spatial approach for censored dependent variables; (ii) a Tobit corner solution model augmented with a spatial lag; (iii) a spatial discrete hazard model. The evidence arising from an investigation of severely state‐constrained local vehicle taxes in Italy suggests that ignoring tax limitations can lead to substantial underestimation of inter‐jurisdictional fiscal interaction. Copyright © 2011 John Wiley & Sons, Ltd.
Canal wall thickness after preparation with NiTi rotary files
Authors: BrkaniĆ Tatjana , Stojšin Ivana , Živković Slavoljub , Vukoje Karolina
Published: October 2011

Root canal preparation is the most important phase of endodontic procedure and it consists of adequate canal space cleaning and shaping. In recent years, rotary instruments and techniques have gained importance because of the great efficacy, speed, and safety of the preparation procedure. AIM: The aim of this research was to investigate measurement of maximal and minimal residual dentine thickness (RDT) and canal diameter after the canal preparation with different NiTi rotary files. METHODS: The research has been conducted on extracted human teeth in vitro conditions. The teeth have been divided in seven groups (20 teeth per group) depending on the kind of instruments used for root canal preparation: ProTaper, GT, ProFile, K‐3, FlexMaster, hand ProTaper, and hand GT. The canals have been shaped in a crown‐down manner and irrigated with 5.25% sodium hypochlorite. The roots of the teeth have been cut 1 and 3 mm from the apex. Apical preparation quality has been assessed under the polarized light microscope. RESULTS: The maximal residual dentine thickness at distance 1 mm from apex, ranged from 1.16 to 1.45 mm, and at distance 3 mm from apex, from 1.44 to 1.84 mm. The minimal dentine thickness at distance 1 mm from apex ranged from 0.52 to 0.73 mm, and at distance 3 mm from apex, from 0.66 to 0.83 mm. The canal diameters after preparation at distance 1 mm from apex ranged from 0.42 to 0.49 mm, and at distance 3 mm from apex, from 0.53 to 0.63 mm. CONCLUSIONS: There was no significant difference neither in maximal and minimal RDT, nor in canal diameters shaped with different NiTi instruments tested. All tested NiTi files have accomplished good quality preparation of apical root canal parts. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
MRT letter: Contrast‐enhanced computed tomographic imaging of soft callus formation in fracture healing
Authors: Hayward Lauren Nicole Miller , Bakker Chantal Marie‐Jeanne DE , Lusic Hrvoje , Gerstenfeld Louis Charles , Grinstaff Mark W. , Morgan Elise Feng‐i
Published: October 2011

Formation of a cartilaginous soft callus at the site of a bone fracture is a pivotal stage in the healing process. Noninvasive, or even nondestructive, imaging of soft callus formation can be an important tool in experimental and pre‐clinical studies of fracture repair. However, the low X‐ray attenuation of cartilage renders the soft callus nearly invisible in radiographs. This study utilized a recently developed, cationic, iodinated contrast agent in conjunction with micro‐computed tomography to identify cartilage in fracture calluses in the femora of C57BL/6J and C3H/HeJ mice. Fracture calluses were scanned before and after incubation in the contrast agent. The set of pre‐incubation images was registered against and then subtracted from the set of post‐incubation images, resulting in a three‐dimensional map of the locations of cartilage in the callus, as labeled by the contrast agent. This map was then compared to histology from a previous study. The results showed that the locations where the contrast agent collected in relatively high concentrations were similar to those of the cartilage. The contrast agent also identified a significant difference between the two strains of mice in the percentage of the callus occupied by cartilage, indicating that this method of contrast‐enhanced computed tomography may be an effective technique for nondestructive, early evaluation of fracture healing. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
MRT letter: Expression of ATP sensor protein in Caenorhabditis elegans
Authors: Kishikawa Jun‐Ichi , Fujikawa Makoto , Imamura Hiromi , Yasuda Kayo , Noji Hiroyuki , Ishii Naoaki , Mitani Shohei , Yokoyama Ken
Published: October 2011

Adenosine 5′‐triphosphate (ATP) is the major energy currency and is involved in many biological processes. The ATP‐monitoring system for cells in animals can be helpful to study the relationship between energy metabolism and biological processes. The fluorescent ATP biosensor ATeam (ATP indicator based on Epsilon subunit for Analytical Measurements), which has been reported to monitor ATP levels in cultured cells on the basis of fluorescence resonance energy transfer (FRET), was introduced into nematodes by microinjection and UV‐irradiation method. To confirm whether ATeam functions as an ATP sensor in nematode cells, the authors measured FRET of ATeam in cells of transgenic nematode. The ATeam was expressed in target cells in nematode. In vulva cells, ATP levels in the cytosol were higher than those in mitochondria. ATeam also sensed ATP level change in cultured cells from the transgenic nematode. These experiments indicated that ATeam is available for detection of changes in ATP levels in nematode cells. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Pocket card and dedicated feedback session to improve feedback to ward residents: A randomized trial
Authors: Peccoralo Lauren , Karani Reena , Coplit Lisa , Korenstein Deborah
Published: October 2011

BACKGROUND:

Residents are often dissatisfied with feedback received on the wards, and hospital attendings are often uncomfortable and unskilled at giving feedback.

OBJECTIVE:

Determine the impact of a pocket card and feedback session on Internal Medicine (IM) residents' perceptions of feedback and attendings' comfort giving feedback.

DESIGN:

Prospective randomized trial using chi‐square analysis.

SETTING:

Inpatient wards at 1 academic medical center.

PARTICIPANTS:

One hundred eleven IM residents and 36 attendings.

INTERVENTION:

We introduced a pocket feedback card, structured around the Accreditation Council for Graduate Medical Education competencies, and a feedback session to guide mid‐rotation feedback. Control group attendings received the usual reminder to provide feedback.

MEASUREMENTS:

Attendings' and residents' survey responses, after the inpatient month, assessing attitudes towards feedback and qualitative interviews with intervention attendings.

RESULTS:

Intervention residents were more likely than controls to report sufficient and useful feedback from attendings. They reported more feedback regarding skills needing improvement and how to improve their skills (51.3% vs 25.5%, P = 0.02), and felt their clinical (61.5% vs 27.8%, P = 0.001) and professionalism/communication (51.3% vs 29.1%, P = 0.03) skills improved based on this feedback. Intervention attendings, as compared to controls, agreed that residents improved their professionalism/communication skills (76.9% vs 31.1%, P = 0.02) based on feedback. Most intervention attendings found the card and session acceptable and would use both in the future.

CONCLUSIONS:

A pocket feedback card and dedicated feedback session improved the quantity and quality of feedback delivered to IM residents by their attendings on the inpatient wards. Journal of Hospital Medicine 2011;. © 2011 Society of Hospital Medicine
Inpatient staffing within pediatric residency programs: Work hour restrictions and the evolving role of the pediatric hospitalist
Authors: Oshimura Jennifer , Sperring Jeffrey , Bauer Benjamin D. , Rauch Daniel A.
Published: October 2011

OBJECTIVE:

In October 2010, the Accreditation Council for Graduate Medical Education (ACGME) mandated new standards that will further restrict resident work hours. There is growing concern surrounding the impact these restrictions will have on the staffing of inpatient services. The objective of this study was to survey the landscape of pediatric resident coverage of noncritical care inpatient teaching services prior to the implementation of these guidelines. In addition, we sought to explore how changes in work hour restrictions might affect the role of pediatric hospitalists in training programs.

METHODS:

In January 2010, an institutional review board (IRB)‐approved electronic survey was sent to 196 US residency training programs via the Association of Pediatric Program Directors (APPD) listserve.

RESULTS:

One hundred twenty responses were received representing 5201 pediatric residents. Of the programs that responded, 84% have hospitalists. At programs with hospitalists (n = 97), 24% have pediatric hospitalist attendings in‐house at night. Nearly a quarter of responding programs (22%) reported having no attending physicians in‐house at night. At the time of our survey, 31% of programs anticipated the addition of 24‐hour in‐house hospitalist coverage within the next 5 years. When the additional work hour restrictions are implemented, 70% of programs anticipated the need to add additional hospitalist coverage at night.

CONCLUSIONS:

Significant variation exists in how pediatric teaching services provide overnight coverage. While hospitalists are prevalent in pediatric training programs (84% overall, 67% day only), their role in direct patient care during the overnight hours has been limited thus far. New work hour restrictions will promote the need for more hospitalists. Journal of Hospital Medicine 2012;. © 2011 Society of Hospital Medicine.
Severe acute hypertension among inpatients admitted from the emergency department
Authors: Shorr Andrew F. , Zilberberg Marya D. , Sun Xiaowu , Johannes Richard S. , Gupta Vikas , Tabak Ying P.
Published: October 2011

BACKGROUND:

Hospitalists often treat patients with severe acute hypertension (AH) presenting to the hospital. Little is known about the epidemiology of this syndrome.

OBJECTIVE:

To examine the prevalence of severe AH in patients admitted through the emergency department (ED) and its associated outcomes.

DESIGN:

A cohort study using retrospectively collected vital signs and other clinical data.

PATIENTS:

A total of 1,290,804 adults admitted between 2005 and 2007.

SETTING:

One hundred fourteen acute‐care hospitals.

MEASUREMENTS:

Severe AH was defined as at least 1 systolic blood pressure (SBP) >180 mmHg. We used multivariable regression to estimate AH‐attributable in‐hospital mortality, need for mechanical ventilation (MV), and length of stay (LOS).

RESULTS:

Severe AH occurred in 178,131 (13.8%) patients. Disease categories with the highest prevalence were nervous (29.0%), circulatory (16.0%), endocrine (14.7%), and kidney/urinary (13.5%). The overall in‐hospital mortality was 3.6%. The relationship between severe AH strata and mortality was graded for nervous system diseases; mortality rates for each 10 mmHg increase in SBP from 180 to >220 mmHg were 6.5%, 8.1%, 9.9%, 12.0%, and 19.7%, respectively (P < 0.0001). The relationship between severe AH strata and need for MV was graded in the most pronounced way in respiratory and circulatory conditions (P < 0.0001). The relationship between severe AH strata and LOS was graded in most disease categories (P < 0.0001).

CONCLUSIONS:

Severe AH appears common and its prevalence varies by underlying clinical condition. Severe AH is associated with excess in‐hospital mortality for patients with nervous system diseases and, for most disease categories, prolongs hospitalization. Journal of Hospital Medicine 2011;. © 2011 Society of Hospital Medicine