bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular genetics of supernumerary tooth formation
Authors: Wang Xiu‐Ping , Fan Jiabing
Published: January 2011

Despite advances in the knowledge of tooth morphogenesis and differentiation, relatively little is known about the aetiology and molecular mechanisms underlying supernumerary tooth formation. A small number of supernumerary teeth may be a common developmental dental anomaly, while multiple supernumerary teeth usually have a genetic component and they are sometimes thought to represent a partial third dentition in humans. Mice, which are commonly used for studying tooth development, only exhibit one dentition, with very few mouse models exhibiting supernumerary teeth similar to those in humans. Inactivation of Apc or forced activation of Wnt/β(catenin signalling results in multiple supernumerary tooth formation in both humans and in mice, but the key genes in these pathways are not very clear. Analysis of other model systems with continuous tooth replacement or secondary tooth formation, such as fish, snake, lizard, and ferret, is providing insights into the molecular and cellular mechanisms underlying succesional tooth development, and will assist in the studies on supernumerary tooth formation in humans. This information, together with the advances in stem cell biology and tissue engineering, will pave ways for the tooth regeneration and tooth bioengineering. genesis 49:261–277, 2011. © 2011 Wiley‐Liss, Inc.
Mover design and simulation of linear synchronous motor with half‐wave‐rectified self‐excitation
Authors: Hirayama Tadashi , Higuchi Tsuyoshi , Abe Takashi , Oyama Jun
Published: January 2011

This paper presents a design method for a linear synchronous motor with half‐wave‐rectified self‐excitation; this method enables the construction of a motor with small thrust ripple. The mover of the motor is designed to be asymmetrical in order to reduce the thrust ripple. First, we design the configuration of the asymmetrical mover and the field winding of the mover by using the finite element method and a characteristic equation. The asymmetrical mover is built, and the thrust ripple reduction is verified by experiments. Next, the linear synchronous motor is modeled using a circuit simulator in order to confirm its high‐speed performance. The operation characteristics are clarified by simulation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(1): 43–52, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21051
Creatine kinase brain overexpression protects colorectal cells from various metabolic and non‐metabolic stresses
Authors: Mooney Steven M. , Rajagopalan Krithika , Williams Brenten H. , Zeng Yu , Christudass Christhunesa S. , Li Youqiang , Yin Bo , Kulkarni Prakash , Getzenberg Robert H.
Published: January 2011

Creatine kinase brain (CKB) is one of three cytosolic isoforms of creatine kinase that is predominantly expressed in the brain. The enzyme is overexpressed in a wide variety of cancers, with the exception of colon cancer, where it is downregulated. The significance of this downregulation remains poorly understood. Here, we demonstrate that overexpression of CKB‐C283S, a dominant‐negative construct that lacks the kinase function but retains its ability to dimerize, causes remarkable changes in cell shape, adhesion, and invasion. Furthermore, it results in increased expression of stromal cell markers such as PAGE4 and SNAIL, suggesting an epithelial‐to‐mesenchymal transition (EMT) in these cells. In cells transfected with a CKB‐expressing construct, CKB localizes not only to the cytosol but also to the nucleus, indicating a structural or kinase role unrelated to ATP storage. Furthermore, overexpression of CFP‐tagged wild‐type (WT) CKB in Caco‐2 colon cancer cells dramatically increased the number of cells in G2/M but had little effect on cell proliferation. Taken together, these data demonstrate that the downregulation of CKB may play an important role in colon cancer progression by promoting EMT. J. Cell. Biochem. 112: 1066–1075, 2011. © 2011 Wiley‐Liss, Inc.
Interference with ER‐α enhances the therapeutic efficacy of the selective CDK inhibitor roscovitine towards ER‐positive breast cancer cells
Authors: Węsierska‐Gądek Józefa , Gritsch David , Zulehner Nora , Komina Oxana , Maurer Margarita
Published: January 2011

In recent years many risk factors for the development of breast cancer that are linked to estrogens have been identified, and roscovitine (ROSC), a selective cyclin‐dependent kinase (CDK) inhibitor, has been shown to be an efficient inhibitor of the proliferation of human breast cancer cells. Therefore, we have examined the possibility that interference with estrogen signaling pathways, using tamoxifen (TAM), a selective estrogen receptor modulator (SERM), could modulate the efficacy of treatment with ROSC. In conjunction with TAM, ROSC exhibited enhanced anti‐proliferative activity and CDK inhibition, particularly in estrogen‐dependent MCF‐7 cells. The interaction between both drugs was synergistic. However, in ER‐α‐negative cells the interaction was antagonistic. Exposure of MCF‐7 cells to ROSC abolished the activating phosphorylation of CDK2 and CDK7 at Ser164/170. This in turn prevented the phosphorylation of the carboxyl‐terminal repeat domain of RNA Polymerase II and ER‐α at Ser118, resulting in the down‐regulation of the latter. Concomitantly, wt p53 was strongly activated by phosphorylation at Ser46. Our results demonstrate that ROSC negatively affects the functional status of ER‐α, making it potentially useful in the treatment of estrogen‐dependent breast cancer cells. J. Cell. Biochem. 112: 1103–1117, 2011. © 2011 Wiley‐Liss, Inc.
Comparative morphology of the gonadal structure related to reproductive strategies in six species of neotropical catfishes (Teleostei: Siluriformes)
Authors: Melo Rafael Magno Costa , Arantes Fábio Pereira , Sato Yoshimi , dos Santos José Enemir , Rizzo Elizete , Bazzoli Nilo
Published: January 2011

We studied the relationship between the morphology of the reproductive system and the reproductive strategies of six neotropical catfishes using macroscopic and microscopic analyses. The reproductive system of the examined Siluriformes showed diversified characteristics, but permitted their being grouped according to three reproductive strategies: pelagic spawning, demersal spawning, and internally fertilizing. The pelagic spawners Pseudoplatystoma corruscans and Conorhynchos conirostris have testes that are characterized by filiform lobes, absence of testicular secretion, full‐grown oocytes of small diameter, thin zona radiata, and cuboidal follicular cells. Pimelodus maculatus is morphologically distinct from the other two pelagic spawners catfishes due to the presence of testicular secretion. The demersal spawners Lophiosilurus alexandri and Rhinelepis aspera possess homogeneous testicular secretion, large mature oocytes, and columnar follicular cells. The most specialized reproductive system was observed in the internally fertilizing Trachelyopterus galeatus, which possesses a seminal vesicle accessory to the testes, spermatozoa with elongated nuclei that form spermatozeugmata, and a secretory ovarian lamellar epithelium that is associated with sperm storage. The reproductive system observed in Neotropical catfishes showed a relationship associated with the type of fertilization and the reproductive strategies of the six species studied. © 2011 Wiley‐Liss, Inc.
Age, sex, body anthropometry, and ACL size predict the structural properties of the human anterior cruciate ligament
Authors: Hashemi Javad , Mansouri Hossein , Chandrashekar Naveen , Slauterbeck James R. , Hardy Daniel M. , Beynnon Bruce D.
Published: January 2011

Anterior cruciate ligament (ACL) injury continues to be at the forefront of sports injury concerns because of its impact on quality of life and joint health prognosis. One strategy is to reduce the occurrence of this injury by identifying at‐risk subjects based on key putative risk factors. The purpose of our study was to develop models that predict the structural properties of a subject's ACL based on the combination of known risk factors. We hypothesized that the structural properties of the ACL can be predicted using a multi‐linear regression model based on significant covariates that are associated with increased risk of injury, including age, sex, body size, and ACL size. We also hypothesized that ACL size is a significant contributor to the model. The developed models had predictive capabilities for the structural properties of the ACL: load at failure (R2 = 0.914), elongation at failure (R2 = 0.872), energy at failure (R2 = 0.913), and linear stiffness (R2 = 0.756). Furthermore, sex, age, body mass, BMI, and height were contributors (p < 0.05) to all predicted structural properties. ACL minimal area was a contributor to elongation, energy at failure, and linear stiffness (p < 0.05), but not to load at failure. ACL volume was also a contributor to elongation and energy at failure (p < 0.05), but not to linear stiffness and load at failure models. ACL length was not a significant contributor to any structural property. The clinical significance of this research is its potential, after continued development and refinement of the model, for application to prognostic studies that are designed to identify individuals at increased risk for injury to the ligament. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 993–1001, 2011
Monitoring and assessment of land degradation and desertification: Towards new conceptual and integrated approaches
Authors: Vogt J. V. , Safriel U. , Von Maltitz G. , Sokona Y. , Zougmore R. , Bastin G. , Hill J.
Published: January 2011

The implementation of the United Nations Convention to Combat Desertification (UNCCD) needs agreed, scientifically sound and practical methodologies for monitoring and assessing the state and trend of land degradation as well as for monitoring the performance of management programmes. The lack of sufficient and integrated monitoring and assessment (M&A) has in the past been identified as a major constraint for combating desertification. Implementing efficient M&A programmes, however, requires careful analysis of the information needs of the different stakeholders, a clear scientific concept of the processes and drivers of land degradation and an analysis of the theoretical and practical possibilities for adequate M&A. This paper briefly analyses the information needs of diverse stakeholders, reviews existing M&A systems, and highlights key aspects for a scientifically sound approach to monitoring and assessment. Analysis of existing approaches shows that in spite of their relevance, standardised procedures for their implementation at operational scales are lacking. This is partly attributable to the lack of agreed and clear definitions, related difficulties in defining and hence in measuring the attributes chosen to represent land degradation and desertification and the varying degrees of paucity of field data. There is also the urgent need to better integrate bio‐physical and socio‐economic aspects of desertification through a suitably robust scientific framework that links the drivers, processes and symptoms of desertification. Such a framework will allow for the identification of key variables to be monitored and will provide a basis for an improved forecasting and assessment of vulnerability, thereby providing highly important information for policy‐ and decision‐making. Copyright © 2011 John Wiley & Sons, Ltd.
The in vitro PDT efficacy of a novel metallophthalocyanine (MPc) derivative and established 5‐ALA photosensitizing dyes against human metastatic melanoma cells
Authors: Robertson C.A. , Abrahamse H.
Published: January 2011

Background and Objective

Numerous worldwide clinical trials have shown that photodynamic therapy (PDT) represents an effective and safe modality for various skin disorders, but little research has been done in terms of its effect on malignant melanomas (MM). Thus, the aim of this study was to compare the effect of both established porphyrin photosensitizer 5‐aminolevulinic acid (5‐ALA) and novel metallophthalocyanine (MPc) photosensitizer on human metastatic skin cells which produce a MM.

Materials and Methods

The cellular responses following PDT were assessed using changes in cell morphology, cell viability, cytotoxicity, apoptosis, and proliferation.

Results

Findings reported that in vitro human MM cell line A375 (EACC no: 88113005) are highly sensitive to growth inhibition and apoptosis induction by the cytotoxic side‐effects induced by MPc and 5‐ALA photosensitizing treatments post‐laser irradiation at 680 and 636 nm, respectively. The decrease of cell viability accompanied by an increased cytotoxicity and apoptotic and necrotic levels, with a time‐dependant decrease in cellular proliferation was found to be far more significant for MPc‐treated cells than 5‐ALA‐treated cells, since MPc was applied in far lower concentrations and exhibited far less photoxicity to control cells.

Conclusion

Hence, novel MPc proved to be the better photosensitizing dye for metastatic melanoma tumor destruction in combination with laser irradiation and is a particularly attractive photosensitizer since it exhibits so many ideal properties of a photosensitizing agent, thus further research of this possible anticancer agent could contribute to its potential application in PDT cancer treatment of MMs. Lasers Surg. Med. 42:926–936, 2010. © 2010 Wiley‐Liss, Inc.
Structure elucidation and complete NMR spectral assignment of an unusual aromatic monacolin analog from Monascus purpureus‐fermented rice
Authors: Liu Ming‐Tao , Li Jin‐Jie , Shang Xiao‐Ya , Li Shuai , Li Ling‐Ling , Luan Na , Jin Zong‐Lian
Published: January 2011

One unusual aromatic monacolin analog, monacophenyl, was isolated from the ethanolic extract of Monascus purpureus‐fermented rice. Its structure was completely and unambiguously assigned by one‐ and two‐dimensional NMR techniques (1H NMR, 13C NMR, HSQC, HMBC and NOESY) and high‐resolution ESI‐MS spectrometry. Copyright © 2011 John Wiley & Sons, Ltd.
Anodic oxidation of selenadiazoloquinolones in alkaline media
Authors: Staško Andrej , Zalibera Michal , Barbieriková Zuzana , Rimarčík Ján , Lukeš Vladimír , Bella Maroš , Milata Viktor , Brezová Vlasta
Published: January 2011

Newly synthesized derivatives of 6‐oxo‐6,9‐dihydro[1,2,5]selenadiazolo[3,4‐h]quinoline variously substituted at position 7 (R = H, COOH, COCH3, CN, COOC2H5 and COOCH3) are established in strongly alkaline aqueous solutions (0.1 M NaOH; pH ∼ 13) as N(9)‐deprotonated structures, but in less alkaline solutions (0.001 M NaOH; pH ∼ 11) the N(9)‐protonated oxo tautomeric forms dominate. Upon their anodic oxidation in alkaline solutions, the selenadiazole ring is replaced, forming instead the paramagnetic species analogous to the ortho semiquinone radical anions as monitored by in situ EPR spectroscopy. The quantum chemical calculations for two representative selenadiazoloquinolones (R = H and COOH) and their anodic oxidation products presented are in agreement with experiments. Copyright © 2011 John Wiley & Sons, Ltd.
Low‐power composite CPMG HSQMBC experiment for accurate measurement of long‐range heteronuclear coupling constants
Authors: Boros Sándor , Kövér Katalin E.
Published: January 2011

A modified version of CPMG‐HSQMBC pulse scheme is presented for the measurement of long‐range heteronuclear coupling constants. The method implements adiabatic inversion and refocusing pulses on the heteronucleus. Low‐power composite 180° XY‐16 CPMG pulse train is applied on both proton and X nuclei during the evolution of long‐range couplings to eliminate phase distortions due to co‐evolution of homonuclear proton–proton couplings. The pulse sequence yields pure absorption antiphase multiplets allowing precise and direct measurement of the nJXH coupling constants regardless from the size of the proton‐proton couplings. The applicability of the method is demonstrated using strychnine as a model compound. The selective 1D version of the method is also presented. Copyright © 2011 John Wiley & Sons, Ltd.
The medicine use and corresponding subjective health complaints among adolescents, a cross‐national survey
Authors: Gobina Inese , Välimaa Raili , Tynjälä Jorma , Villberg Jari , Villerusa Anita , Iannotti Ronald J. , Godeau Emmanuelle , Gabhainn Saoirse Nic , Andersen Anette , Holstein Bjørn E. ,   the HBSC Medicine Use Writing Group
Published: January 2011

Background

Medicine use among children and young people is under‐researched. Studies that investigated cross‐national patterns in adolescents' medicine use practice are rare. This study aims to investigate adolescents' medicine use for corresponding health complaints in Europe and USA.

Methods

Nationally representative samples of adolescents from 19 countries and regions in Europe and USA completed an anonymous, standardised questionnaire as part of the Health Behaviour in School‐aged Children 2005/2006 survey. The prevalence of health complaints and medicine use were determined. The influence of the frequency of medicine use, age, gender and country of residence, on the likelihood of medicine use was assessed using multilevel multivariate logistic regression, with separate analyses for boys and girls.

Results

Both health complaints and medicine use were common among adolescents. Medicine use was strongly associated with the frequency of health complaints. The prevalence of both medicine use and health complaints was higher among girls than boys. Boys and girls with weekly health complaints were both similarly likely to report elevated rates of medicine use.

Conclusions

The findings indicated that adolescents who report more frequent recurrent health complaints are also more likely to report more frequent medicine use for their health complaints. Adolescent boys with weekly health complaints have the same risk of medicine use as girls with weekly health complaints. The importance of educating school‐aged children to interpret their bodily feelings and complaints and to use medicines appropriately is of high priority. Copyright © 2011 John Wiley & Sons, Ltd.
Retracted:Effects of nanoparticles to the dynamical behavior of polymer chains in semidilute polymer solution: A dynamic light scattering study
Authors: Mondal Mojammel H.
Published: January 2011

The following article from the Journal of Polymer Science Part B: Polymer Physics: “Effects of nanoparticles to the dynamical behavior of polymer chains in semidilute polymer solution: A dynamic light scattering study,” by Mojammel H. Mondal, published online on 18 January 2011 in Wiley Online Library (onlinelibrary.wiley.com), has been retracted by agreement between the author, the journal Managing Editor, Dr. Victoria Cleave, and Wiley‐Blackwell. The retraction has been made as the research article was submitted without the author's PhD supervisor and principal investigator's knowledge or consent. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Clinical, radiological, and physiological differences between obliterative bronchiolitis and problematic severe asthma in adolescents and young adults: The early origins of the overlap syndrome?
Authors: Bandeira Teresa , Negreiro Filipa , Ferreira Rosário , Salgueiro Marisa , Lobo Luísa , Aguiar Pedro , Trindade J.C.
Published: January 2011

Purpose

Few reports have compared chronic obstructive lung diseases (OLDs) starting in childhood.

Aims

To describe functional, radiological, and biological features of obliterative bronchiolitis (OB) and further discriminate to problematic severe asthma (PSA) or to diagnose a group with overlapping features.

Results

Patients with OB showed a greater degree of obstructive lung defect and higher hyperinflation (P < 0.001). The most frequent high‐resolution computed tomography (HRCT) features (increased lung volume, inspiratory decreased attenuation, mosaic pattern, and expiratory air trapping) showed significantly greater scores in OB patients. Patients with PSA have shown a higher frequency of atopy (P < 0.05). ROC curve analysis demonstrated discriminative power for the LF variables, HRCT findings and for atopy between diagnoses. Further analysis released five final variables more accurate for the identification of a third diagnostic group (FVC%t, post‐bronchodilator ΔFEV1 in ml, HRCT mosaic pattern, SPT, and D. pteronyssinus‐specific IgE).

Conclusions

We found that OB and PSA possess identifiable characteristic features but overlapping values may turn them undistinguishable. Pediatr. Pulmonol. 2011; 46:580–580. © 2011 Wiley‐Liss, Inc.
NMR solution structure of a cyanovirin homolog from wheat head blight fungus
Authors: Matei Elena , Louis John M. , Jee JunGoo , Gronenborn Angela M.
Published: January 2011

Members of the cyanovirin‐N homolog (CVNH) lectin family are found in bacteria, fungi and plants. As part of our ongoing work on CVNH structure‐function studies, we determined the high‐resolution NMR solution structure of the homolog from the wheat head blight disease causing ascomycetous fungus Gibberella zeae (or Fusarium graminearum), hereafter called GzCVNH. Like cyanovirin‐N (CV‐N), GzCVNH comprises two tandem sequence repeats and the protein sequence exhibits 30% identity with CV‐N. The overall structure is similar to those of other members of the CVNH family, with the conserved pseudo‐symmetric halves of the structure, domains A and B, closely resembling recently determined structures of Tuber borchii, Neurospora crassa, and Ceratopteris richardii CVNH proteins. Although GzCVNH exhibits a similar glycan recognition profile to CV‐N and specifically binds to Manα(1‐2)Manα, its weak carbohydrate binding affinity to only one binding site is insufficient for conferring anti‐HIV activity. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Structure, dynamics, and Hck interaction of full‐length HIV‐1 Nef
Authors: Jung Jinwon , Byeon In‐Ja L. , Ahn Jinwoo , Gronenborn Angela M.
Published: January 2011

Nef is an HIV accessory protein that plays an important role in the progression of disease after viral infection. It interferes with numerous signaling pathways, one of which involves serine/threonine kinases. Here, we report the results of an NMR structural investigation on full‐length Nef and its interaction with the entire regulatory domain of Hck (residues 72–256; Hck32L). A helical conformation was found at the N‐terminus for residues 14–22, preceding the folded core domain. In contrast to the previously studied truncated Nef (Nef Δ1‐39), the full‐length Nef did not show any interactions of Trp57/Leu58 with the hydrophobic patch formed by helices α1 and α2. Upon Hck32L binding, the N‐terminal anchor domain as well as the well‐known SH3‐binding site of Nef exhibited significant chemical shift changes. Upon Nef binding, resonance changes in the Hck spectrum were confined mostly to the SH3 domain, with additional effects seen for the connector between SH3 and SH2, the N‐terminal region of SH2 and the linker region that contains the regulatory polyproline motif. The binding data suggest that in full‐length Nef more than the core domain partakes in the interaction. The solution conformation of Hck32L was modeled using RDC data and compared with the crystal structure of the equivalent region in the inactivated, full‐length Hck, revealing a notable difference in the relative orientations of the SH3 and SH2 domains. The RDC‐based model combined with 15N backbone dynamics data suggest that Hck32L adopts an open conformation without binding of the polyproline motif in the linker to the SH3 domain. Proteins 2011; © 2011 Wiley‐Liss, Inc.
New benchmark metrics for protein‐protein docking methods
Authors: Gao Mu , Skolnick Jeffrey
Published: January 2011

With the development of many computational methods that predict the structural models of protein‐protein complexes, there is a pressing need to benchmark their performance. As was the case for protein monomers, assessing the quality of models of protein complexes is not straightforward. An effective scoring scheme should be able to detect substructure similarity and estimate its statistical significance. Here, we focus on characterizing the similarity of the interfaces of the complex and introduce two scoring functions. The first, the interfacial Template Modeling score (iTM‐score), measures the geometric distance between the interfaces, while the second, the Interface Similarity score (IS‐score), evaluates their residue‐residue contact similarity in addition to their geometric similarity. We first demonstrate that the IS‐score is more suitable for assessing docking models than the iTM‐score. The IS‐score is then validated in a large‐scale benchmark test on 1562 dimeric complexes. Finally, the scoring function is applied to evaluate docking models submitted to the Critical Assessment of Prediction of Interactions (CAPRI) experiments. While the results according to the new scoring scheme are generally consistent with the original CAPRI assessment, the IS‐score identifies models whose significance was previously underestimated. Proteins 2011. © 2011 Wiley‐Liss, Inc.
Mechanism of reactant and product dissociation from the anthrax edema factor: A locally enhanced sampling and steered molecular dynamics study
Authors: Martínez Leandro , Malliavin Thérèse E. , Blondel Arnaud
Published: January 2011

The anthrax edema factor is a toxin overproducing damaging levels of cyclic adenosine mono‐phosphate (cAMP) and pyrophosphate (PPi) from ATP. Here, mechanisms of dissociation of ATP and products (cAMP, PPi) from the active site are studied using locally enhanced sampling (LES) and steered molecular dynamics simulations. Various substrate conformations and ionic binding modes found in crystallographic structures are considered. LES simulations show that PPi and cAMP dissociate through different solvent accessible channels, while ATP dissociation requires significant active site exposure to solvent. The ionic content of the active site directly affects the dissociation of ATP and products. Only one ion dissociates along with ATP in the two‐Mg2+ binding site, suggesting that the other ion binds EF prior to ATP association. Dissociation of reaction products cAMP and PPi is impaired by direct electrostatic interactions between products and Mg2+ ions. This provides an explanation for the inhibitory effect of high Mg2+ concentrations on EF enzymatic activity. Breaking of electrostatic interactions is dependent on a competitive binding of water molecules to the ions, and thus on the solvent accessibility of the active site. Consequently, product dissociation seems to be a two‐step process. First, ligands are progressively solvated while preserving the most important electrostatic interactions, in a process that is dependent on the flexibility of the active site. Second, breakage of the electrostatic bonds follows, and ligands diffuse into solvent. In agreement with this mecanism, product protonation facilitates dissociation. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Dissociation curves and binding energies of diatomic transition metal carbides from density functional theory
Authors: Goel Satyender , Masunov Artëm E.
Published: January 2011

The computational description of the catalytic processes on the surface of transition metals (TMs) requires methods capable of accurate prediction of the bond forming and breaking between the atoms of metal and other elements. In our previous report [Goel and Masunov, J Chem Phys, 129, 214302, 2008], we studied TM hydrides and found that Boese–Martin functional for kinetics (BMK) combined with broken symmetry approach described dissociation process more accurately than multireference wavefunction theory (WFT) methods and some other functionals. Here, we investigate the binding energy, geometry, electronic structure, and potential energy curves for diatomic TM carbides using several exchange‐correlation functionals. The functionals that include explicit dependence on the kinetic energy density (τ‐functionals) are considered, among others. We have found M05‐2x performance to be the best, followed by BMK, when compared with experimental and high level WFT energetics. This agreement deteriorates quickly for other functionals when the fraction of the Hartree–Fock exchange is decreased. Scalar relativistic corrections yield mixed results for bond lengths and bond energies. The natural bond orbital analysis provides useful insight in description of stable spin state over others in these diatomics. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Theoretical study of the kojic acid structure in gas phase and aqueous solution
Authors: Kakkar Rita , Singh Chayannika
Published: January 2011

Density functional calculations at the B3LYP/6‐311++G** level have been performed to determine the ground‐state conformational preference for kojic acid, a widely used skin‐whitening, antibrowning, and antibacterial agent. It is found that the gas phase consists almost entirely of the 5‐hydroxy‐2‐(hydroxymethyl)‐4H‐pyran‐4‐one tautomer, although several rotamers of this are prevalent. In aqueous solution, however, other tautomers are also present. The validity of the calculations is confirmed by the observed FTIR, NMR, and UV–vis spectra, which show good correspondence with the theoretical spectra. The electronic interactions are interpreted in terms of charge and bond order analysis as well as the composition of the HOMO and LUMO. The calculations show that kojic acid has partial aromatic character and is a good nucleophile. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Quantum chemical studies on the structure and detonation properties of the fused polynitrodiazoles: New high energy density molecules
Authors: Ravi P. , Gore G.M. , Tewari Surya P. , Sikder A. K.
Published: January 2011

In this study, we explore the possibility that fused polynitrodiazoles act as high energy density materials. Density functional theory calculations at the B3LYP/aug‐cc‐pVDZ level were performed to predict the structure, energy of explosion (≈1.68 kcal g−1), density (≈1.98 g cm−3), detonation velocity (≈9.50 km s−1), and detonation pressure (≈41.50 GPa) of model molecules. The predicted properties have been found to be promising compared with 3,4,5‐trinitro‐1H‐pyrazole, 1,3,5‐trinitro‐1,3,5‐triazinane, and octahydro‐1,3,5,7‐tetranitro‐l,3,5,7‐tetraazocane. The nature of azoles of the molecule presumably determines the geometry, stability, sensitivity, density, and detonation performance. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Performance evaluation of MIMO–WCDMA cellular networks in multiuser frequency selective fading environments
Authors: Gkonis P. K. , Tsoulos G. V. , Kaklamani D. I.
Published: January 2011

This paper investigates the performance of different transmission strategies for multiple input multiple output (MIMO) networks with the wideband code division multiple access (WCDMA) air interface as the physical layer protocol. Performance is evaluated statistically with extended Monte Carlo (MC) simulations in terms of achievable bit‐error (BER) rate in frequency selective fading cellular environments. As results indicate, for a MIMO configuration withMtantennas at the base station (BS),Mrantennas per mobile station (MS) andLresolvable multipath components, the transmission strategy based on signal to noise ratio (SNR) enhancement is the optimum transmit solution forMt ≤ Mr. However, the pre‐RAKE maximal ratio combining transmission strategy outerperforms the SNR enhancement strategy with post‐RAKE processing forMt > Mr, high number of resolvable multipath components and channel estimation error up to 40%. Moreover, a transmission scheme based on the maximization of the ratio of the desired MS's signal to the total amount of interference that causes to the network is proposed, and is shown that outerperforms the conventional transmission schemes for high data rate services. For symmetric MIMO configurations (Mt = Mr) and two resolvable multipath components, this strategy provides 30% BER gain compared to the maximization of SNR strategy. This gain can be further improved by 25% with a proposed adjacent sector cooperation algorithm. Copyright © 2011 John Wiley & Sons, Ltd.
Milk composition in free‐ranging polar bears (Ursus maritimus) as a model for captive rearing milk formula
Authors: Hedberg Gail E. , Derocher Andrew E. , Andersen Magnus , Rogers Quinton R. , DePeters Edward J. , Lönnerdal Bo , Mazzaro Lisa , Chesney Russell W. , Hollis Bruce
Published: January 2011

The goals of this study were to have an improved understanding of milk composition and to help create a suitable milk formula for cubs raised in captivity. Milk samples were evaluated for fat, fatty acids, carbohydrate, vitamin D3, 25(OH)D3, vitamin A (retinol), vitamin E (α‐tocopherol), protein, and amino acids. Total lipids in milk did not differ for cubs (mean ± SEM = 26.60 ± 1.88 g/100 ml vs. yearlings 27.80 ± 2.20 g/100 ml). Milk lipids were of 23.6% saturated fatty acid for cubs and 22.4% for yearlings. Milk consumed by cubs and yearlings contained 43.8 and 42.0% mono‐unsaturated fatty acids and 23.4 and 21.9% polyunsaturated fatty acids, respectively. Carbohydrate content was higher in milk for cubs (4.60 ± 0.64 g/100 ml) than for yearlings (2.60 ± 0.40 g/100 ml). Vitamin D3concentration of milk was 18.40 ± 5.00 ng/ml in early lactation compared with 7.60 ± 2.00 ng/ml for mid‐lactation. 25(OH)D3was lower in milk consumed by cubs (162.00 ± 6.70 pg/ml) than in milk consumed by yearlings (205.00 ± 45.70 pg/ml). Vitamin A concentrations were 0.06 ± 0.01 and 0.03 ± 0.01 µg/ml for cubs and yearlings, respectively. Vitamin E was higher in milk consumed by cubs (20.16 ± 4.46 µg/ml) than by yearlings (7.30 ± 1.50 µg/ml). Protein content did not differ in milk available to cubs (11.40 ± 0.80 g/100 ml compared with milk for yearlings 11.80 ± 0.40 g/100 ml). Taurine was the most abundant free amino acid at 3,165.90 ± 192.90 nmol/ml (0.04% as fed basis). Zoo Biol 30:550–565, 2011. © 2011 Wiley Periodicals, Inc.
Emergency contraception in the context of marriage in Upper Egypt
Authors: Shaaban Omar M. , Fathalla Mohamed M.F. , Shahin Ahmed Y. , Nasr Ahmed
Published: January 2011

Objective

To explore the degree of knowledge, perception, and practice of emergency contraception (EC) within marital relations in Egypt.

Methods

The present study was a pilot cross‐sectional survey. Eligible participants were randomly selected from 4 governorates in Upper Egypt. A questionnaire was designed by the investigators and administered to an unselected sample of healthcare providers and potential users of EC. The questionnaire collected information in 4 domains: demographics; knowledge about EC; attitudes toward EC; and practice of EC in Egypt.

Results

In total, 240 healthcare providers and 60 potential users of EC completed the questionnaire. Approximately 85% of healthcare providers and 30% of potential users had heard about EC. A similar proportion of study participants said that EC methods are needed. Only 32.7% of healthcare providers and very few potential users had actually used EC.

Conclusion

There is a need for EC in Egypt. However, a big gap in knowledge leads to nonuse or incorrect use of EC and negative attitude toward it. If health service planners and policy makers could fill this gap, a considerable decline in the prevalence of unwanted pregnancy may be achieved by using EC.
Half a century of “muddling”: Are we there yet?
Authors: Rothmayr Allison Christine , Saint-Martin Denis
Published: January 2011

Half a century after the publication of Lindblom's seminal article “The Science of Muddling Through”, we revisit the heritage of incrementalism in this special issue, analyzing its legacy in public policy and public administration. The articles discuss the extent to which recent theoretical developments have transformed the original idea, reinforced it, or possibly rendered it obsolete. In this introductory article, we provide a short overview over the core elements of incrementalism and assess how the concept is used in scholarly publications and research today. We thereby focus on incrementalism as an analytical concept rather then a prescriptive theory. We argue that even after a half a century of “muddling”, we are not yet through with incrementalism. Some of the ideas that underpin the concept of incrementalism continue to drive research, often in combination with more recent theoretical approaches to the policy process. After half a century, incrementalism is still part of the policy scholar's tool kit.
Cryostratigraphy of late Pleistocene syngenetic permafrost (yedoma) in northern Alaska, Itkillik River exposure
Authors: Kanevskiy M. , Shur Y. , Fortier D. , Jorgenson M.T. , Stephani E.
Published: January 2011

Extremely ice-rich syngenetic permafrost, or yedoma, developed extensively under the cold climate of the Pleistocene in unglaciated regions of Eurasia and North America. In Alaska, yedoma occurs in the Arctic Foothills, the northern part of the Seward Peninsula, and in interior Alaska. A remarkable 33-m-high exposure along the lower Itkillik River in northern Alaska opened an opportunity to study the unmodified yedoma, including stratigraphy, particle-size distribution, soil carbon contents, morphology and quantity of segregated, wedge, and thermokarst-cave ice. The exposed permafrost sequence comprised seven cryostratigraphic units, which formed over a period from > 48,000 to 5,00014C yr BP, including: 1) active layer; 2) intermediate layer of the upper permafrost; 3–4) two yedoma silt units with different thicknesses of syngenetic ice wedges; 5) buried peat layer; 6) buried intermediate layer beneath the peat; and 7) silt layer with short ice wedges. This exposure is comparable to the well known Mus-Khaya and Duvanny Yar yedoma exposures in Russia. Based on our field observations, literature sources, and interpretation of satellite images and aerial photography, we have developed a preliminary map of yedoma distribution in Alaska.
COST-EFFECTIVENESS AND DISABILITY DISCRIMINATION – ADDENDUM
Authors: Brock D.
Published: January 2011

In my article above, I cite an earlier article by Frances Kamm, ‘Deciding Whom to Help, Health-Adjusted Life Years, and Disabilities’, in Public Health, Ethics, and Equity, eds. S. Anand, F. Peters, and A. Sen (New York: Oxford University Press, 2004) (which was based on ‘Deciding Whom to Help, the Principle of Irrelevant Goods and Health-Adjusted Life Years’ (1999) circulated as a working paper of the Center for Population Studies, Harvard University). However, (1) I failed to correctly identify her position on one view that she took up in that article, and (2) also failed to cite a proposal she developed in that article similar to one I took up in my paper.
Changes in meal pattern among Norwegian children from 2001 to 2008
Authors: Øverby Nina , Stea Tonje H , Vik Frøydis N , Klepp Knut-Inge , Bere Elling
Published: January 2011

Objective

The present study aimed to analyse changes in meal pattern among Norwegian children from 2001 to 2008 in general; to analyse associations between meal pattern and gender, parental educational level and number of parents in the household; and to analyse the association between intake of unhealthy snacks, meal pattern and the mentioned variables.

Design

Within the Fruits and Vegetables Make the Marks (FVMM) project, two cross-sectional studies were conducted, one in 2001 and one in 2008, where participants from the same schools filled in a questionnaire on meals eaten the previous day.

Subjects

Participants were 6th and 7th grade pupils,n1488 in 2001 andn1339 in 2008.

Setting

Twenty-seven elementary schools in two Norwegian counties.

Results

There were no significant changes in children's meal pattern from 2001 to 2008. For both years more than 90 % of the participants reported that they had breakfast yesterday, while 95 % had lunch, 94 % had dinner and 82 % had supper. More girls than boys reported that they had lunch yesterday (96 %v. 94 %,P= 0·03). More children with higherv. lower educated parents reported that they had breakfast yesterday (93 %v. 88 %,P< 0·001). More children living with two parentsv. one parent had breakfast (93 %v. 88 %,P= 0·001) and lunch yesterday (97 %v. 93 %,P< 0·001).

Conclusions

There were no changes in meal pattern from 2001 to 2008 among Norwegian children. Characteristics associated with skipping meals were living in a one-parent family and having lower educated parents.
Noether symmetries, energy–momentum tensors, and conformal invariance in classical field theory
Authors: Pons Josep M.
Published: January 2011

In the framework of classical field theory, we first review the Noether theory of symmetries, with simple rederivations of its essential results, with special emphasis given to the Noether identities for gauge theories. With this baggage on board, we next discuss in detail, for Poincaré invariant theories in flat spacetime, the differences between the Belinfante energy–momentum tensor and a family of Hilbert energy–momentum tensors. All these tensors coincide on shell but they split their duties in the following sense: Belinfante's tensor is the one to use in order to obtain the generators of Poincaré symmetries and it is a basic ingredient of the generators of other eventual spacetime symmetries which may happen to exist. Instead, Hilbert tensors are the means to test whether a theory contains other spacetime symmetries beyond Poincaré. We discuss at length the case of scale and conformal symmetry, of which we give some examples. We show, for Poincaré invariant Lagrangians, that the realization of scale invariance selects a unique Hilbert tensor which allows for an easy test as to whether conformal invariance is also realized. Finally we make some basic remarks on metric generally covariant theories and classical field theory in a fixed curved background.
Gravitational repulsion within a black hole using the Stueckelberg quantum formalism
Authors: Ludwin D. M. , Horwitz L. P.
Published: January 2011

We wish to study an application of Stueckelberg's relativistic quantum theory in the framework of general relativity. We study the form of the wave equation of a massive body in the presence of a Schwarzschild gravitational field. We treat the mathematical behavior of the wavefunction also around and beyond the horizon (r = 2M). Classically, within the horizon, the time component of the metric becomes spacelike and distance from the origin singularity becomes timelike, suggesting an inevitable propagation of all matter within the horizon to a total collapse at r = 0. However, the quantum description of the wavefunction provides a different understanding of the behavior of matter within the horizon. We find that a test particle can almost never be found at the origin and is more probable to be found at the horizon. Matter outside the horizon has a very small wavelength and therefore interference effects can be found only on a very small atomic scale. However, within the horizon, matter becomes totally “tachyonic” and is potentially “spread” over all space. Small location uncertainties on the atomic scale become large around the horizon, and different mass components of the wavefunction can therefore interfere on a stellar scale. This interference phenomenon, where the probability of finding matter decreases as a function of the distance from the horizon, appears as an effective gravitational repulsion.
Some consequences of experiments with a plasmonic quantum eraser for plasmon tomography
Authors: Grave de Peralta L. , Lopez-Boada R. , Ruiz-Columbié A. , Park S. , Bernussi A. A.
Published: January 2011

We discuss two important consequences of recent experiments using surface plasmon polariton (SPP) tomography in a quantum eraser arrangement. In these experiments surface-emission images were modified by manipulating the polarization state of the leakage radiation. We show that SPP tomography does have the potential to produce images that mirror with high fidelity the propagation and interference of SPP beams at the metal–air interface of a sample. We reveal the physical mechanism behind this capability of SPP tomography. In addition, we show how SPP tomography can be used to detect photons passing through the dark fringes of an interference pattern and why photons propagate in such a way that looks like a photon can propagate across a region where it is never observed.
Determination of satellite valley position in GaN emitter from photoexcited field emission investigations
Authors: Semenenko M. , Yilmazoglu O. , Hartnagel H. L. , Pavlidis D.
Published: January 2011

Argon plasma etched GaN field-emitter rods with nanometer-scale diameter were fabricated on GaN grown on an n+-GaN substrate. Their electron field emission properties were investigated both without and under illumination by using light sources with various wavelengths. The Fowler–Nordheim current-voltage characteristics of the cathodes show a change in slope for illuminated cathodes. The electron affinity difference ΔE between the different valleys in the conduction band has been ascertained and is in the range from 1.18 up to 1.21 eV.
Strong Stark effect in electroluminescence from phosphorous-doped silicon-on-insulator metal-oxide-semiconductor field-effect transistors
Authors: Noborisaka J. , Nishiguchi K. , Ono Y. , Kageshima H. , Fujiwara A.
Published: January 2011

We report a strong Stark effect in electroluminescence (EL) from thin silicon-on-insulator metal-oxide-semiconductor field-effect transistors. The EL peak shows a large Stark shift of up to 50 meV when a gate-induced electric field is applied. Such a large shift is observed because of the strong confinement of carriers by a Si/SiO2 quantum well. Furthermore, we observe a sudden decrease of EL intensity at a specific electric field. This feature is ascribed to electron dissociation from phosphorous atom to subbands in a triangular well at the Si/SiO2 interface by the applied electric field.
Comparison of physical and technical performance in European soccer match‐play: FA Premier League and La Liga
Authors: Dellal Alexandre , Chamari Karim , Wong Del P. , Ahmaidi Said , Keller Dominique , Barros Ricardo , Bisciotti Gian Nicola , Carling Christopher
Published: January 2011

The aim of this study was to compare match performance in professional soccer players across two major European championships: Spanish La Liga and English FA Premier League (FAPL). Data were collected using a computerized match analysis system. A total of 5938 analyses were recorded during the 2006–2007 season. The players were classified into six positional roles: central defenders, full backs, central defensive midfielders, wide midfielders, central attacking midfielders, and forwards. The match performance variables analysed included: (i) physical activity – total distance covered, distances covered at high‐intensities both with and without possession of the ball; (ii) technical actions – heading and ground duels, passing, time in possession, and ball touches. Comparison of the total distance covered by FAPL and La Liga players showed no difference across individual playing positions but FAPL players generally covered greater distances in sprinting. In contrast, more of the total distance in sprinting was covered by La Liga players when their team was in possession (values from P < 0.05 to P < 0.001), while an equal total sprint distance, irrespective of possession, was observed in FAPL players. La Liga players won more heading duels (49.32% vs. 48.68%) and performed the same proportion of successful passes (76.17%). FAPL wide midfielders had ~20% more ball touches per possession than their La Liga counterparts (2.24±0.54 vs. 2.03±0.55, P < 0.001). In conclusion, our results show that FAPL and La Liga teams present differences in various physical and technical aspects of match‐play, suggesting that cultural differences may exist across professional soccer leagues and playing positions.