bluuebunny/crossref_metadata_2025 huggingface dataset:
Expectation–maximization‐based joint data detection and channel estimation for a cellular multi‐carrier code division multiple access network using single‐hop relaying
Authors: Kabaoğlu Nihat
Published: November 2011

This paper is concerned with channel estimation and data detection for a cellular multi‐carrier code division multiple access network using single‐hop relaying in the presence of frequency selective fading channels. The proposed expectation–maximization (EM) algorithm was used to jointly estimate both the coefficients of the channel between a relay and a base station and the data. EM algorithm is particularly suited to multi‐carrier code division multiple access systems because they have multi‐carrier signal format. The considered network uses single‐hop relaying technique to provide a higher quality transmission to the users with low quality channels. The base station (managing mechanism) gives them an opportunity to send their messages via the users with high quality channels in a time sharing mode. The performance of the proposed EM algorithm, with and without hopping and with cooperative communication technique, was analyzed by a computer simulation, and the results are presented. Copyright © 2011 John Wiley & Sons, Ltd.
Three QTL in the honey bee Apis mellifera L. suppress reproduction of the parasitic mite Varroa destructor
Authors: Behrens Dieter , Huang Qiang , Geßner Cornelia , Rosenkranz Peter , Frey Eva , Locke Barbara , Moritz Robin F. A. , Kraus F. B.
Published: November 2011

Varroa destructor is a highly virulent ectoparasitic mite of the honey bee Apis mellifera and a major cause of colony losses for global apiculture. Typically, chemical treatment is essential to control the parasite population in the honey bee colony. Nevertheless a few honey bee populations survive mite infestation without any treatment. We used one such Varroa mite tolerant honey bee lineage from the island of Gotland, Sweden, to identify quantitative trait loci (QTL) controlling reduced mite reproduction. We crossed a queen from this tolerant population with drones from susceptible colonies to rear hybrid queens. Two hybrid queens were used to produce a mapping population of haploid drones. We discriminated drone pupae with and without mite reproduction, and screened the genome for potential QTL using a total of 216 heterozygous microsatellite markers in a bulk segregant analysis. Subsequently, we fine mapped three candidate target regions on chromosomes 4, 7, and 9. Although the individual effect of these three QTL was found to be relatively small, the set of all three had significant impact on suppression of V. destructor reproduction by epistasis. Although it is in principle possible to use these loci for marker‐assisted selection, the strong epistatic effects between the three loci complicate selective breeding programs with the Gotland Varroa tolerant honey bee stock.
Chemoenzymatic Synthesis of Stegobinone and Stegobiol, Components of the Natural Sex Pheromone of the Drugstore Beetle (Stegobium paniceum L.)
Authors: Kalaitzakis Dimitris , Smonou Ioulia
Published: November 2011

NADPH‐dependent ketoreductases were used for the chemoenzymatic stereoselective synthesis of the two componentsof the natural sex pheromone of the drugstore beetle. The key step in the asymmetric synthesis was the enzymatic reduction of an α‐methyl‐1,3‐diketone and an α‐methyl‐β‐keto ester, which finally led to the preparation of crystalline stegobinone and stegobiol.
Bace1 processing of NRG1 type III produces a myelin‐inducing signal but is not essential for the stimulation of myelination
Authors: Velanac Viktorija , Unterbarnscheidt Tilmann , Hinrichs Wilko , Gummert Maike N. , Fischer Tobias M. , Rossner Moritz J. , Trimarco Amelia , Brivio Veronica , Taveggia Carla , Willem Michael , Haass Christian , Möbius Wiebke , Nave Klaus‐Armin , Schwab Markus H.
Published: November 2011

Myelin sheath thickness is precisely adjusted to axon caliber, and in the peripheral nervous system, neuregulin 1 (NRG1) type III is a key regulator of this process. It has been proposed that the protease BACE1 activates NRG1 dependent myelination. Here, we characterize the predicted product of BACE1‐mediated NRG1 type III processing in transgenic mice. Neuronal overexpression of a NRG1 type III‐variant, designed to mimic prior cleavage in the juxtamembrane stalk region, induces hypermyelination in vivo and is sufficient to restore myelination of NRG1 type III‐deficient neurons. This observation implies that the NRG1 cytoplasmic domain is dispensable and that processed NRG1 type III is sufficient for all steps of myelination. Surprisingly, transgenic neuronal overexpression of full‐length NRG1 type III promotes hypermyelination also in BACE1 null mutant mice. Moreover, NRG1 processing is impaired but not abolished in BACE1 null mutants. Thus, BACE1 is not essential for the activation of NRG1 type III to promote myelination. Taken together, these findings suggest that multiple neuronal proteases collectively regulate NRG1 processing. © 2011 Wiley Periodicals, Inc.
Gene–environment interactions of novel variants associated with head and neck cancer
Authors: Liang Caihua , Marsit Carmen J. , Houseman E. Andres , Butler Rondi , Nelson Heather H. , McClean Michael D. , Kelsey Karl T.
Published: November 2011

Background

A genome‐wide association study for upper aerodigestive tract cancers identified 19 candidate single‐nucleotide polymorphisms (SNPs). We used these SNPs to investigate the potential gene–gene and gene–environment interactions in head and neck squamous cell carcinoma (HNSCC) risk.

Methods

The 19 variants were genotyped using Taqman assays among 575 cases and 676 controls in our population‐based case–control study.

Results

A restricted cubic spline model suggested both ADH1B and HEL308 modified the association between smoking pack‐years and HNSCC. Classification and regression tree analysis demonstrated a higher‐order interaction between smoking status, ADH1B, FLJ13089, and FLJ35784 in HNSCC risk. Compared with ever smokers carrying ADH1B T/C+T/T genotypes, smokers carrying ADH1B C/C genotype and FLJ13089 A/G+A/A genotypes had the highest risk of HNSCC (odds ratio = 1.84).

Conclusions

Our results suggest that the risk associated with these variants may be specifically important among specific exposure groups. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Role of insulin‐like growth factor‐II mRNA‐binding protein‐3 in invadopodia formation and the growth of oral squamous cell carcinoma in athymic nude mice
Authors: Hwang Young Sun , Park Kwang‐Kyun , Cha In Ho , Kim Jin , Chung Won‐Yoon
Published: November 2011

Background

The invadopodia are specialized structures that degrade the extracellular matrix (ECM) and promote cell invasion and metastasis. Understanding the forms and functions of invadopodia should facilitate the proper identification of novel targets for antiinvasive therapy.

Methods

To understand the role of insulin‐like growth factor‐II mRNA‐binding protein‐3 (IMP‐3) in invadopodia formation and cancer invasion, we performed IMP‐3 gene silencing, invadopodia formation, ECM degradation assay, zymography, western blot, and mouse xenograft.

Results

We demonstrate that invadopodia evidenced ECM degradation activity in oral squamous cell carcinoma (OSCC). Downregulation of IMP‐3 inhibited invadopodia formation, ECM degradation, and tumor growth and invasiveness. Epidermal growth factor receptor (EGFR) signaling may perform a critical function in invadopodia formation, ECM degradation, IMP‐3, and cortactin expression.

Conclusion

IMP‐3 may be intimately correlated with cancer invasion through invadopodia in oral cancer. The overexpression of IMP‐3 in oral cancer was predictive of a high correlation with cancer growth and invasion. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Donor site morbidity of free ulnar forearm flap
Authors: Tan Swee T. , James Dylan W. , Moaveni Zachary
Published: November 2011

Background

The purpose of this study was to evaluate the donor site morbidity of the free ulnar forearm flap (UFF).

Methods

Consecutive patients undergoing free UFF between 1982 and 2009 were retrospectively reviewed. In addition, detailed assessment of hand function and donor site cosmesis was performed in the most recent 50 patients followed up for at least 12 months.

Results

In all, 62 of the 242 free UFF donor sites (26%) were closed directly and the remainder required split thickness skin grafting. Donor site complications included total (n = 1) and partial (n = 17) skin graft loss and persistent hypertrophic scarring (n = 4). There was minimal incidence of cold intolerance, parasthesia, and pain; no reduction in joint mobility, grip and pinch strength, and sensory dysfunction, with excellent donor site cosmesis.

Conclusions

UFF has several advantages, including the possibility of direct closure of the donor defect, and reduced morbidity and excellent donor site cosmesis. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Age‐ and time‐dependent changes in cancer incidence among immigrants to Sweden: colorectal, lung, breast and prostate cancers
Authors: Mousavi Seyed Mohsen , Fallah Mahdi , Sundquist Kristina , Hemminki Kari
Published: November 2011

To examine the role of gender, age at immigration and length of stay on incidence trends of common cancers, we studied risk of colorectal, lung, breast and prostate cancers in immigrants to Sweden from 1958 to 2008. The nationwide Swedish Family‐Cancer Database was used to calculate standardized incidence ratios for common cancers among immigrants compared to Swedes. Immigrants were classified into “high‐risk” countries when their risk was increased, into “low‐risk” when their risk was decreased and into “other” when their risk was nonsignificant. Among those who immigrated at younger age (<30 years), we found an increasing trend for colorectal cancer risk in low‐risk men and high‐risk women. Among those who immigrated at older age (≥30 years), a decreasing lung cancer risk in high‐risk men and an increasing breast cancer risk in low‐risk women were observed. The increasing trend of prostate cancer risk was independent of age at immigration. The risk trends for “other” immigrants were between the risks of low‐ and high‐risk countries. The gender‐specific shifts in cancer risks in immigrants toward the risk in natives indicate a major role of sex, age at immigration and environmental exposures in colorectal and lung cancers risks. In contrast, the unchanged trend of breast cancer among those who immigrated at younger ages and an increasing trend for those who migrated at older ages may suggest a limited effect for environmental exposures, especially at younger age. Our study points out a role of age at immigration on the risk trend of cancer.
Ketamine induces motor neuron toxicity and alters neurogenic and proneural gene expression in zebrafish
Authors: Kanungo Jyotshna , Cuevas Elvis , Ali Syed F. , Paule Merle G.
Published: November 2011

Ketamine, a noncompetitive antagonist of N‐methyl‐d‐aspartate‐type glutamate receptors, is a pediatric anesthetic that has been shown to be neurotoxic in rodents and nonhuman primates when administered during the brain growth spurt. Recently, the zebrafish has become an attractive model for toxicity assays, in part because the predictive capability of the zebrafish model, with respect to chemical effects, compares well with that from mammalian models. In the transgenic (hb9:GFP) embryos used in this study, green fluorescent protein (GFP) is expressed in the motor neurons, facilitating the visualization and analysis of motor neuron development in vivo. In order to determine whether ketamine induces motor neuron toxicity in zebrafish, embryos of these transgenic fish were treated with different concentrations of ketamine (0.5 and 2.0 mm). For ketamine exposures lasting up to 20 h, larvae showed no gross morphological abnormalities. Analysis of GFP‐expressing motor neurons in the live embryos, however, revealed that 2.0 mm ketamine adversely affected motor neuron axon length and decreased cranial and motor neuron populations. Quantitative reverse transcriptase‐polymerase chain reaction analysis demonstrated that ketamine down‐regulated the motor neuron‐inducing zinc finger transcription factor Gli2b and the proneural gene NeuroD even at 0.5 mm concentration, while up‐regulating the expression of the proneural gene Neurogenin1 (Ngn1). Expression of the neurogenic gene, Notch1a, was suppressed, indicating that neuronal precursor generation from uncommitted cells was favored. These results suggest that ketamine is neurotoxic to motor neurons in zebrafish and possibly affects the differentiating/differentiatedneurons rather than neuronal progenitors. Published 2011. This article is a US Government work and is in the public domain in the USA.
Ronacaleret, a calcium-sensing receptor antagonist, increases trabecular but not cortical bone in postmenopausal women
Authors: Fitzpatrick Lorraine A , Dabrowski Christine E , Cicconetti Gregory , Gordon David N , Fuerst Thomas , Engelke Klaus , Genant Harry K
Published: November 2011

Intermittent injections of parathyroid hormone have osteoanabolic effects that increase bone mineral density (BMD). Ronacaleret is an orally administered calcium-sensing receptor antagonist that stimulates endogenous parathyroid hormone release from the parathyroid glands. Our objective was to compare the effects of ronacaleret and teriparatide on volumetric BMD (vBMD) measured by quantitative computed tomography (QCT). We conducted a randomized, placebo-controlled, dose-ranging trial at 45 academic centers with 31 sites participating in the substudy. Patients included 569 postmenopausal women with low bone mineral density; vBMD was assessed at the spine and hip in a subset of 314 women. Patients were treated for up to 12 months with open-label teriparatide 20 µg subcutaneously once daily or randomly assigned in a double-blind manner to ronacaleret 100 mg, 200 mg, 300 mg, or 400 mg once daily, alendronate 70 mg once weekly, or matching placebos. Ronacaleret increased spine integral (0.49% to 3.9%) and trabecular (1.8% to 13.3%) vBMD compared with baseline, although the increments were at least twofold lower than that attained with teriparatide (14.8% and 24.4%, respectively) but similar or superior to that attained with alendronate (5.0% and 4.9%, respectively). There were small non-dose-dependent decreases in integral vBMD of the proximal femur with ronacaleret (−0.1 to −0.8%) compared with increases in the teriparatide (3.9%) and alendronate (2.7%) arms. Parathyroid hormone (PTH) elevations with ronacaleret were prolonged relative to that seen historically with teriparatide. Ronacaleret preferentially increased vBMD of trabecular bone that is counterbalanced by small decreases in BMD at cortical sites. The relative preservation of trabecular bone and loss at cortical sites are consistent with the induction of mild hyperparathyroidism with ronacaleret therapy. © 2012 American Society for Bone and Mineral Research
An efficient multicomponent and stereoselective synthesis of new spiro[indeno[1,2‐b]quinoxaline‐11,2′‐pyrrolidine] derivatives
Authors: Moemeni Mehdi , Arvinnezhad Hamid , Samadi Saadi , Tajbakhsh Mahmood , Jadidi Khosrow , Khavasi Hamid Reza
Published: November 2011

New spiro[indeno[1,2‐b]quinoxaline‐11,2′‐pyrrolidine] derivatives were prepared in high yield stereoselectively from an efficient multicomponent 1,3‐dipolar cycloaddition reaction between ninhydrin, phenylenediamine, sarcosine, and chalcones. The regiochemistry and stereochemistry of resultant cycloadducts have been determined by several 2D NMR spectroscopic techniques and X‐ray single crystal diffraction. J. Heterocyclic Chem., (2012).
Comparison of modeling techniques in circuit variability analysis
Authors: Yelten Mustafa Berke , Franzon Paul D. , Steer Michael B.
Published: November 2011

Three nonlinear reduced‐order modeling approaches are compared in a case study of circuit variability analysis for deep submicron complementary metal‐oxide‐semiconductor technologies where variability of the electrical characteristics of a transistor can be significantly detrimental to circuit performance. The drain currents of 65 nm N‐type metal‐oxide‐semiconductor and P‐type metal‐oxide‐semiconductor transistors are modeled in terms of a few process parameters, terminal voltages, and temperature using Kriging‐based surrogate models, neural network‐based models, and support vector machine‐based models. The models are analyzed with respect to their accuracy, establishment time, size, and evaluation time. It is shown that Kriging‐based surrogate models and neural network‐based models can be generated with sufficient accuracy that they can be used in circuit variability analysis. Numerical experiments demonstrate that for smaller circuits, Kriging‐based surrogate modeling yields results faster than the neural network‐based models for the same accuracy whereas for larger circuits, neural network‐based models are preferred as, in all metrics, better performance is obtained. Within‐die variations for an XOR circuit are analyzed, and it is shown that the nonlinear reduced‐order models developed can more effectively capture the within‐die variations than the traditional process corner analysis. Copyright © 2011 John Wiley & Sons, Ltd.
Finite difference approximations and dynamics simulations for the Lévy Fractional Klein‐Kramers equation
Authors: Li Can , Deng Weihua , Wu Yujiang
Published: November 2011

The Klein‐Kramers equation describes position and velocity distribution of Langevin dynamics, the diffusion equation and Fokker‐Planck equation are its special cases for characterizing position distribution and velocity distribution, respectively. Incorporating the mechanisms of Lévy flights into the Klein‐Kramers formalism leads to the Lévy fractional Klein‐Kramers equation, which can effectively describe Lévy flights in the presence of an external force field in the phase space. For numerically solving the Lévy fractional Klein‐Kramers equation, this article presents the explicit and implicit finite difference schemes. The discrete maximum principle is generalized, using this result the detailed stability and convergence analyses of the schemes are given. And the extrapolation and some other possible techniques for improving the convergent rate or making the schemes efficient in more general cases are also discussed. The extensive numerical experiments are performed to confirm the effectiveness of the numerical schemes or simulate the superdiffusion processes. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2011
Diagnostic delay in pediatric solid tumors: A population based study on determinants and impact on outcomes
Authors: Loh Amos Hong Pheng , Aung LeLe , Ha Christina , Tan Ah‐Moy , Quah Thuan Chong , Chui Chan‐Hon
Published: November 2011

Background

Despite socioeconomic and clinical progress, pediatric tumors continue to present in advanced stage, and may be due to delays in diagnosis. This study aimed to identify factors associated with diagnostic delay (time between symptom onset and diagnosis) in pediatric tumors in a population‐based study, and to assess the impact of delay on subsequent outcome.

Procedure

Natural logarithm of delay was retrospectively described for 390 newly diagnosed tumors reported to the Singapore Childhood Cancer Registry from 1997 to 2007. Delay was correlated with socio‐demographic, disease and healthcare‐system factors using multivariate linear regression, and with event‐free survival (EFS) using Cox regression analysis.

Results

Total median delay was 5.3 weeks (range 0.1–283.1). Shorter delay was independently associated with younger patient age (P = 0.006), abdominal and pelvic sites (P < 0.001 and P = 0.036, respectively), incidental diagnoses by healthcare staff (P = 0.002), and when pediatric emergency units were the first contacted healthcare facilities and the first to raise suspicion of malignancy (P = 0.034, and P = 0.018, respectively). These factors explained only a small percentage of variance in delay times (21%). Delay was not associated with EFS and disease stage, with 24% of tumors presenting in stage 4.

Conclusions

Diagnostic delay was independently associated with age and site of presentation, and points of first symptom detection, first healthcare contact, and first suspicion of malignancy. The broad range of clinical variables analyzed could only account in a small way for differences in delay times observed. While overall delay times were short, they did not influence disease stage at presentation and eventual outcome. Pediatr Blood Cancer 2012; 58: 561–565. © 2011 Wiley Periodicals, Inc.
Gender differences in positive social–emotional functioning
Authors: Romer Natalie , Ravitch N. Kathryn , Tom Karalyn , Merrell Kenneth W. , Wesley Katherine L.
Published: November 2011

We investigated gender differences of children and adolescents on positive social and emotional competencies using a new strength‐based measure of positive social–emotional attributes and resilience—the Social–Emotional Assets and Resilience Scales (SEARS) cross‐informant system. Caregivers, teachers, and students in grades kindergarten through 12 from schools across several U.S. states completed SEARS rating scales and self‐report forms. Females were consistently rated as having significantly higher total scores on all versions of the SEARS assessment system (p < .01), indicating consistent perceptions of females' higher levels of social–emotional competencies by all raters. These differences were not impacted by the grade students were in or the gender of the parent or teacher rater. Implications of these findings and future directions are discussed. © 2011 Wiley Periodicals, Inc.
Susceptibility of standard clones and European field populations of the green peach aphid, Myzus persicae, and the cotton aphid, Aphis gossypii (Hemiptera: Aphididae), to the novel anthranilic diamide insecticide cyantraniliprole
Authors: Foster Stephen P , Denholm Ian , Rison Jean‐Luc , Portillo Hector E , Margaritopoulis John , Slater Russell
Published: November 2011

BACKGROUND: Parthenogenetic clones of the green peach aphid, Myzus persicae (Sulzer), and the cotton aphid, Aphis gossypii Glover, were tested with the anthranilic diamide insecticide cyantraniliprole (i.e. DuPont™ Cyazypyr™) in systemic‐uptake bioassays to investigate potential for cross‐resistance conferred by mechanisms of insecticide resistance to organophosphates, carbamates and pyrethroids and, in the case of M. persicae, reduced sensitivity to neonicotinoids. These data were compared with the response of field samples of M. persicae and A. gossypii collected from around Europe.

RESULTS: Cyantraniliprole was not cross‐resisted by any of the known insecticide resistance mechanisms present in M. persicae or A. gossypii. The compound was equally active against resistant and susceptible aphid strains. The responses of the M. persicae field samples were very consistent with a maximum response ratio of 2.9 compared with a standard laboratory clone. The responses of the A. gossypii field samples were more variable, although a majority of the responses were not statistically different.

CONCLUSION: Cyantraniliprole is currently the only anthranilic diamide (IRAC MoA 28) insecticide targeting aphid species such as M. persicae and A. gossypii. There is no evidence to suggest that the performance of this compound is affected by commonly occurring mechanisms that confer resistance to other insecticide chemistries. Cyantraniliprole is therefore a valuable tool for managing insecticide resistance in these globally important pests. Copyright © 2011 Society of Chemical Industry
Zinc related defects in ZnO nanorods
Authors: Travlos Anastasios , Boukos Nikolaos , Chandrinou Chrysoula
Published: November 2011

ZnO nanorods which have been doped with Zn are studied with photoluminescence spectroscopy at low temperature. Detailed photoluminescence studies reveal that the insertion and extraction of Zn in the nanorods creates zinc related intrinsic defects. The optical signature of these defects is located 30 meV below the conduction band minimum.
Phase field modeling of grain growth in thin films on rigid substrates
Authors: Deng Jie
Published: November 2011

A phase field model of grain growth in thin films on rigid substrates is presented, in which the motion of grain boundaries is driven by curvatures as well as anisotropy in surface, interface, and strain energies. The match between the proposed model and the corresponding sharp interface model is demonstrated by asymptotic analysis. The effect of diffuse interface on grain boundary mobility is minimized. The parameters in the model are connected to the measurable properties of materials, and therefore can be obtained from experiments or atomic scale simulations. In numerical simulations, the influence of the texture dependent surface, interface, and strain energies on grain growth is illustrated. The effects of film thickness, strain level, and grain boundary grooving on grain size distribution and texture evolution are also investigated. The effectiveness as well as the limits of the present model are discussed, and the ways to extend it are proposed.
In‐situ X‐ray photoelectron spectroscopy of trimethyl aluminum and water half‐cycle treatments on HF‐treated and O3‐oxidized GaN substrates
Authors: Sivasubramani Prasanna , Park Tae Joo , Coss Brian E. , Lucero Antonio , Huang Jie , Brennan Barry , Cao Yu , Jena Debdeep , Xing Huili (Grace) , Wallace Robert M. , Kim Jiyoung
Published: November 2011

We have investigated the effect of trimethyl aluminum (TMA) and water (H2O) half‐cycle treatments on HF‐treated, and O3‐oxidized GaN surfaces at 300 °C. The in‐situ X‐ray photoelectron spectroscopy results indicate no significant re‐growth of Ga–O–N or self‐cleaning on HF‐treated and O3‐oxidized GaN substrates with exposure to water and TMA. This result is different from the self‐cleaning effect of Ga2O3 seen on sulfur‐treated GaAs or InGaAs substrates. O3 causes aggressive oxidation of GaN substrate and direct O–N bonding compared to H2O. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Giant dielectric constant observed in Ba0.96Sr0.04Zrx Y0.005Ti0.995–xO3–δ ceramics
Authors: Zhang X. S. , Zhang L. , Chen X. Y. , Li J. , Li Z. F. , Yu P.
Published: November 2011

Ba0.96Sr0.04Zrx Y0.005Ti0.995–xO3–δ ceramics were prepared by conventional sintering. The dielectric properties and the Curie temperature of the ceramics were studied. The Ba0.96Sr0.04Zrx Y0.005Ti0.995–xO3–δ ceramics (x = 0.04) exhibit a giant dielectric constant (εr ∼ 105). The peak value of dielectric constant is ∼250,000 at 100 Hz and ∼70,000 at 1 MHz for Ba0.96Sr0.04Zrx Y0.005Ti0.995–xO3–δ ceramics (x = 0.04). The results show that Ba0.96Sr0.04Zrx Y0.005Ti0.995–xO3–δ (x = 0.04) ceramics are a promising candidate material for microelectronic applications. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Critical charges of simple coulomb molecular systems: One‐two electron case
Authors: Turbiner A. V. , Medel Cobaxin H.
Published: November 2011

We consider some Coulomb systems with several infinitely massive centers of charge Z and one or two electrons: (Z,e), (2Z,e), (3Z,e), (4Z,e), (2Z,e,e), and (3Z,e,e). It is shown that the physical, integer charges Z = 1,2,… do not play a distinguished role for the total energy and for the equilibrium configuration of a system, giving no indication of a charge quantization. By definition, a critical charge Zcr for a given Coulomb system (nZ,e) or (nZ,e,e) is a charge which separates the domain of the existence of bound states from the domain of unbound states (the domain of stability), the continuum (the domain of instability). For all the above‐mentioned systems critical charges Zcr as well as equilibrium geometrical configurations are found. Furthermore, an indication to a branch point singularity at Z = Zcr with exponent 3/2 was obtained. It is demonstrated that in the domain of the existence the optimal geometrical configuration for both (nZ,e) at n = 2,3,4 and (nZ,e,e) at n = 2,3 corresponds to the Platonic body. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Determinants of Climate Change Disclosure by Developed and Emerging Countries in Asia Pacific
Authors: Amran Azlan , Periasamy Vinod , Zulkafli Abdul Hadi
Published: November 2011

This research aims to examine some of the generic determinants of company attributes and corporate governance variables and whether there is any relationship to the reporting of climate change strategy. For that purpose, this study investigated firms in 10 industries, across 13 countries. This study is based on climate change disclosures made in the sustainability and annual reports by firms domiciled in developed and emerging countries in Asia Pacific. The study uses content analysis to construct weighted and unweighted disclosure indices. Based on the extant literature, several variables, namely, firm size, industrial membership, country of domicile, environment certification, board size, independent non‐executives, the CEO duality structure and gender were selected and their influence on the level of climate change disclosure was tested empirically. As for agency theory, this study offers both confirmatory and contradictory results regarding board independence. The results reveal that in spite of the fact that the level of climate change disclosure in some emerging countries in Asia Pacific is still low, by increasing the proportion of independent non‐executives on the board of directors, encouragement of firms' practice to separate the CEO‐board chair role, and firm practices in obtaining and maintaining environment certification would directly increase the climate change disclosure in their sustainability reports. Furthermore, firms that demonstrate a lack of gender diversity on the board would increase the climate change reporting system practices. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Involvement of the cGMP pathway in the osthole‐facilitated glutamate release in rat hippocampal nerve endings
Authors: Lin Tzu yu , Lu Cheng Wei , Huang Wei‐jan , Wang Su‐jane
Published: November 2011

Osthole, an active constituent isolated from Cnidium monnieri (L.) Cusson, has previously been shown to have the capacity to increase depolarization‐evoked glutamate release in rat hippocampal nerve terminals. As cGMP‐dependent signaling cascade has been found to modulate glutamate release at the presynaptic level, the aim of this study was to further examine the role of cGMP signaling pathway in the regulation of osthole on glutamate release in hippocampal synaptosomes. Results showed that osthole dose‐dependently increased intrasynaptosomal cGMP levels. The elevation of cGMP levels by osthole was prevented by the phosphodiesterase 5 inhibitor sildenafil but was insensitive to the guanylyl cyclase inhibitor ODQ. In addition, osthole‐induced facilitation of 4‐aminopyridine (4‐AP)‐evoked glutamate release was completely prevented by the cGMP‐dependent protein kinase (PKG) inhibitors, KT5823, and Rp‐8‐Br‐PET‐cGMPS. Direct activation of PKG with 8‐Br‐cGMP or 8‐pCPT‐cGMP also occluded the osthole‐mediated facilitation of 4‐AP‐evoked glutamate release. Furthermore, sildenafil exhibited a dose‐dependent facilitation of 4‐AP‐evoked release of glutamate and occluded the effect of osthole on the 4‐AP‐evoked glutamate release. Collectively, our findings suggest that osthole‐mediated facilitation of glutamate release involves the activation of cGMP/PKG‐dependent pathway. Synapse, 2012. © 2011 Wiley Periodicals, Inc.
A formal approach to adaptive software: continuous assurance of non-functional requirements
Authors: Filieri Antonio , Ghezzi Carlo , Tamburrelli Giordano
Published: November 2011

Modern software systems are increasingly requested to be adaptive to changes in the environment in which they are embedded. Moreover, adaptation often needs to be performed automatically, through self-managed reactions enacted by the application at run time. Off-line, human-driven changes should be requested only if self-adaptation cannot be achieved successfully. To support this kind of autonomic behavior, software systems must be empowered by a rich run-time support that can monitor the relevant phenomena of the surrounding environment to detect changes, analyze the data collected to understand the possible consequences of changes, reason about the ability of the application to continue to provide the required service, and finally react if an adaptation is needed. This paper focuses on non-functional requirements, which constitute an essential component of the quality that modern software systems need to exhibit. Although the proposed approach is quite general, it is mainly exemplified in the paper in the context of service-oriented systems, where the quality of service (QoS) is regulated by contractual obligations between the application provider and its clients. We analyze the case where an application, exported as a service, is built as a composition of other services. Non-functional requirements—such as reliability and performance—heavily depend on the environment in which the application is embedded. Thus changes in the environment may ultimately adversely affect QoS satisfaction. We illustrate an approach and support tools that enable a holistic view of the design and run-time management of adaptive software systems. The approach is based on formal (probabilistic) models that are used at design time to reason about dependability of the application in quantitative terms. Models continue to exist at run time to enable continuous verification and detection of changes that require adaptation.
Indigenous ecological knowledge and natural resource management in the cultural landscape of China's Hani Terraces
Authors: Jiao Yuanmei , Li Xiuzhen , Liang Luohui , Takeuchi Kazuhiko , Okuro Toshiya , Zhang Dandan , Sun Lifang
Published: November 2011

Indigenous ecological knowledge (IEK) can contribute to the management of local ecosystems and landscapes. Cultural landscapes are produced by and reflect the long‐term interactions between humans and nature in indigenous societies. Yunnan Province, located in southwestern China, is the homeland of many ethnic groups, and is also a refuge for numerous species of wild plants and animals. Indigenous people in Yunnan, who have rich ecological knowledge, play an important role in the conservation of local biodiversity and the region's unique terraced agricultural landscapes. We used the Hani people and their outstanding cultural landscape of rice terraces in Yuanyang County of Yunnan Province as a case study to describe their worldview and discuss their formation of IEK; their roles in the preservation of rice landraces and in pest regulation; their management of water, forest, and soil resources; and the vertical landscape pattern and resource‐circulation system that has evolved in the areas managed by the Hani. We also discuss the challenges and threats facing the Hani, their IEK, and their cultural landscape, as well as discuss the potential for integration of the Hani's IEK with modern conservation efforts.
On the Relationships Between Jeffreys Modal and Weighted Likelihood Estimation of Ability Under Logistic IRT Models
Authors: Magis David , Raîche Gilles
Published: November 2011

This paper focuses on two estimators of ability with logistic item response theory models: the Bayesian modal (BM) estimator and the weighted likelihood (WL) estimator. For the BM estimator, Jeffreys’ prior distribution is considered, and the corresponding estimator is referred to as the Jeffreys modal (JM) estimator. It is established that under the three-parameter logistic model, the JM estimator returns larger estimates than the WL estimator. Several implications of this result are outlined.
The impact of African aridity on the isotopic signature of Atlantic deep waters across the Middle Pleistocene Transition
Authors: Malaizé Bruno , Jullien Elsa , Tisserand Amandine , Skonieczny Charlotte , Grousset E. Francis , Eynaud Fr"d"rique , Kissel Catherine , Bonnin J"r"me , Karstens Svenja , Martinez Philippe , Bory Aloys , Bout-Roumazeilles Vivianne , Caley Thibaut , Crosta Xavier , Charlier Karine , Rossignol Linda , Flores Jos"-Abel , Schneider Ralph
Published: November 2011

A high resolution analysis of benthic foraminifera as well as of aeolian terrigenous proxies extracted from a 37 m-long marine core located off the Mauritanian margin spanning the last ~ 1.2 Ma, documents the possible link between major continental environmental changes with a shift in the isotopic signature of deep waters around 1.0–0.9 Ma, within the so-called Mid-Pleistocene Transition (MPT) time period. The increase in the oxygen isotopic composition of deep waters, as seen through the benthic foraminiferaδ18O values, is consistent with the growth of larger ice sheets known to have occurred during this transition. Deep-water massδ13C changes, also estimated from benthic foraminifera, show a strong depletion for the same time interval. This drastic change inδ13C values is concomitant with a worldwide 0.3‰ decrease observed in the major deep oceanic waters for the MPT time period. The phase relationship between aeolian terrigeneous signal increase and thisδ13C decrease in our record, as well as in other paleorecords, supports the hypothesis of a global aridification amongst others processes to explain the deep-water masses isotopic signature changes during the MPT. In any case, the isotopic shifts imply major changes in the end-memberδ18O andδ13C values of deep waters.
A Multi-level Analysis of Thirty-two Societies on Marital and Family Satisfaction
Authors: KAMO YOSHINORI , HORI MAKIKO
Published: November 2011

When we examine the quality of life for each individual, several specific dimensions need to be considered. Health conditions and quality of family relationships are critical. When the individual in question is married, his/her marital quality is important. When he/she has a job, subjective assessment of that job is important. Social relationships regarding friends, neighbors, colleagues, relatives, etc. may be critical also. Although the quality of life is more than the sum of qualities of these specific areas of one's life, it is still determined to a great extent by the qualities of these sub-areas, including marital and family relationships (Proulxet al., 2007).
Termination and Recurrence of Civil War: Which Outcomes Lead to Durable Peace after Civil War?
Authors: OHMURA HIROTAKA
Published: November 2011

This article attempts to answer why some countries experience the recurrence of civil war and others do not. One of the most significant differences between civil war onset and its recurrence is thatthe latter has once experienced termination of civil war,while the former has not. To find the cause of recurrence, this article examines how different war termination types influence the duration of post-civil war peace. Duration analysis of the civil wars between 1944 and 1999 shows that military victory, supported by peacekeeping operations or power-sharing arrangements, leads to the most durable peace in a post-civil war country. Contrary to the accepted wisdom, negotiated peace settlement, even when supported by peacekeeping operations or power-sharing arrangements, is not positively related to post-conflict peace.
Influence of Temporal Overlap on Time Course of the Simon Effect
Authors: Baroni Giulia , Pellicano Antonello , Lugli Luisa , Nicoletti Roberto , Proctor Robert W.
Published: November 2011

Two experiments are reported in which we manipulated relevant and irrelevant stimulus dimensions to assess whether an increase in temporal overlap would influence the time course of a “standard” Simon effect (obtained when visual stimuli are presented on the left/right of the screen and left/right responses are performed with uncrossed hands). This procedure is new in two ways: First, the manipulations were intended to reduce, instead of increase, the distance between conditional and unconditional response-activation processes. Second, we manipulated the relevant and irrelevant stimulus dimensions in a manner that did not vary stimulus onset asynchronies, precues, or go/no go trials, or alter the stimulus quality. Results were consistent with the hypothesis that when the two response processes are shifted closer to each other, the Simon effect would be sustained across time, instead of decreasing as typically found. These findings are discussed in line with the temporal overlap hypothesis and with an automatic activation account.
A Novel Application of Calcium Phosphate-Based Bone Cement as an Adjunct Procedure in Adult Craniofacial Reconstruction
Authors: Ho Samuel , Nallathamby Vigneswaran , Ng Huiwen , Ho Michelle , Wong Marcus
Published: November 2011

Secondary corrective osteotomy of malunited craniofacial fractures can be a challenging proposition. The exposure, extrusion, and palpability of the titanium implants used become a genuine concern especially in areas of relatively thin skin, such as the periorbital region. Restoring a satisfactory contour to the midface is another major task for the plastic surgeon. Bone cement used to reconstruct craniofacial defects has existed for many years. However, most applications have been as a substitute for autogenous bone grafts for defects less than 25 cm2. In this article, we present two cases of malunited facial fractures that underwent corrective osteotomy, during which we felt that despite the conventional osteotomy and reduction techniques, there was still either a small remnant step deformity or suboptimal contour smoothness due to prominence of the implants used. We thus used bone cement as a resurfacing medium over titanium implants to restore good malar contour and reduce the palpability and exposure rate of the titanium implants. We report good patient satisfaction with contour correction with no increase in wound infection rates or any delay in wound healing. There was initial chemosis associated with the use of the bone cement, which resolved in both patients within 3 to 4 weeks. Postoperative computed tomography showed some degree of osteointegration but no fraction of the bone cement. Calcium phosphate bone cement thus presents an attractive adjunctive method for midfacial contour resurfacing, when used in conjunction with conventional osteotomy procedures and as an onlay over prominent titanium implants.
Continuous blade coating for multi-layer large-area organic light-emitting diode and solar cell
Authors: Chen Chun-Yu , Chang Hao-Wen , Chang Yu-Fan , Chang Bo-Jie , Lin Yuan-Sheng , Jian Pei-Siou , Yeh Han-Cheng , Chien Hung-Ta , Chen En-Chen , Chao Yu-Chiang , Meng Hsin-Fei , Zan Hsiao-Wen , Lin Hao-Wu , Horng Sheng-Fu , Cheng Yen-Ju , Yen Feng-Wen , Lin I-Feng , Yang Hsiu-Yuan , Huang Kuo-Jui , Tseng Mei-Rurng
Published: November 2011

A continuous roll-to-roll compatible blade-coating method for multi-layers of general organic semiconductors is developed. Dissolution of the underlying film during coating is prevented by simultaneously applying heating from the bottom and gentle hot wind from the top. The solvent is immediately expelled and reflow inhibited. This method succeeds for polymers and small molecules. Uniformity is within 10% for 5 cm by 5 cm area with a mean value of tens of nanometers for both organic light-emitting diode (OLED) and solar cell structure with little material waste. For phosphorescent OLED 25 cd/A is achieved for green, 15 cd/A for orange, and 8 cd/A for blue. For fluorescent OLED 4.3 cd/A is achieved for blue, 9 cd/A for orange, and 6.9 cd/A for white. For OLED with 2 cm by 3 cm active area, the luminance variation is within 10%. Power conversion efficiency of 4.1% is achieved for polymer solar cell, similar to spin coating using the same materials. Very-low-cost and high-throughput fabrication of efficient organic devices is realized by the continuous blade-only method.
Design of soft magnetic CoSiB metallic glass with low Co contents
Authors: Liang Zhang Ji , Min Wang Ying , Hung Shek Chan
Published: November 2011

Based on the topological models of cluster-lines and crystal clusters destabilization, we propose a modified cluster model for designing metallic glasses based on the proposition that distortion of idealized glass-favoring clusters by addition of solute atoms within their solubility limit can enhance glass forming ability. Using the model, two CoSiB metallic glasses of low Co contents (Co63.1B27Si9.9 and Co65B24.4Si10.6) with good mechanical properties are designed. Despite the similar compositions, these two metallic glasses consist of different clusters, and therefore exhibit different magnetic behaviors. Co63.1B27Si9.9 metallic glass, based on the Co7B3 cluster, shows good soft magnetic properties with low coercivity smaller than 0.9 A/m, while Co65B24.4Si10.6 metallic glass, based on the Co8B3 cluster, exhibits paramagnetic behavior. The origin of these magnetic behaviors was discussed in view of the electronic structures of the metallic glasses. The results indicate that the model was valid not only for glass forming ability but also for tuning properties dominated by short-range orders.
Singlet state relaxation via scalar coupling of the second kind
Authors: Pileio G.
Published: November 2011

The contribution of scalar coupling relaxation of the second kind on the relaxation behaviour of nuclear spin singlet states has been derived. The analytical equation found for the relaxation rate constant of singlet state has been compared to the equation for the relaxation of longitudinal magnetization in order to find the conditions for which the singlet state remains long-lived even in the presence of this scalar relaxation mechanism. These results are relevant when the singlet state is formed in molecules with more than two interacting spins.
Relating charge transport and performance in single-layer graded-composition organic light-emitting devices
Authors: Erickson Nicholas C. , Holmes Russell J.
Published: November 2011

Efficient electrophosphorescence is demonstrated using single-layer organic light-emitting devices (OLEDs) containing fac-tris(2-phenylpyridine) iridium (III) [Ir(ppy)3], bis(1-phenylisoquinoline)-(acetylacetonate) iridium (III) [PQIr], and iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,C2′]picolinate [FIrpic] for emission in the green, red, and blue, respectively. Peak forward-emitted external quantum (ηEQE) and power efficiencies (ηP) of ηEQE = (16.9 ± 0.4)% and ηP = (65.0 ± 1.1)lm/W, ηEQE = (12.0 ± 0.4)% and ηP = (8.3 ± 1.1) lm/W, and ηEQE = (10.9 ± 0.3)% and ηP = (28.1 ± 1.1)lm/W, are obtained for optimized green, red, and blue OLEDs, respectively. Devices are doped uniformly with the phosphorescent guest, and contain a continuously-varying host composition from predominately hole-transporting material (HTM) at the anode to predominately electron transporting material (ETM) at the cathode. The highly tunable composition gradient allows for the optimization of electron-hole charge balance and low-voltage operation while maintaining charge and exciton confinement. For each emitter, the optimum composition gradient is understood by considering the dependence of the electron and hole charge carrier mobilities on HTM:ETM composition.
Avalanche breakdown in microscale VO2 structures
Authors: Zhong Xing , Zhang Xueyu , Gupta Arunava , LeClair P.
Published: November 2011

The mechanism of triggering the metal-insulator transition (MIT) by an external electric field in small scale VO2 structures has been attributed to excess carrier injection, rather than Joule heating. This is in part due to the fact that the delay time for MIT to be induced by Joule heating seems much longer than what is observed. However, modeling the resistivity as a function of temperature, explicitly considering phase coexistence of metallic and insulating states near the MIT, and considering thermal dissipation in realistic structures, we demonstrate that Joule heating can exhibit a self-accelerating, avalanche-like behavior, in which the time scale for thermally driven breakdown can be in the nanosecond regime if the device is small enough. This model matches experimental results of our micrometer scale device quite well. Over-threshold voltages, temperature, and size effects on switching delay time and threshold voltage are discussed.