bluuebunny/crossref_metadata_2025 huggingface dataset:
Dislocation nucleation from surface step in silicon: The glide set versus the shuffle set
Authors: Godet Julien , Hirel Pierre , Brochard Sandrine , Pizzagalli Laurent
Published: July 2009

We have studied the mechanisms of dislocation nucleation from surface defects in silicon submitted to various stresses and temperatures. Molecular dynamics simulations with three classical potentials have shown the existence of two different plastic modes in silicon which can be activated from surfaces. At high temperatures and low stresses dislocations nucleation occurs in the {111} glide set planes, while at low temperatures and large stresses it occurs in the {111} shuffle set planes. The analysis of dislocation cores and kinks shows structures like those well known in bulk silicon. This study supports the idea that plasticity in crystalline Si structures could be governed by dislocation nucleation from surfaces.
Correctness of a particular solution of inverse problem in rocking curve imaging
Authors: Huber Isabella , Mikulík Petr , Baumbach Tilo
Published: July 2009

Local lattice misorientations on crystalline substrates can be visualized by rocking curve imaging. Local deviations from Bragg peak positions are extracted from a series of digital topographs recorded by a CCD detector under different azimuths. Bragg peaks from surface regions such as crystallites with a larger local misorientation overlap on the detector, which requires a back‐projection method in order to reconstruct the misorientation components on the sample surface from the measured angular position on the detector planes. From mathematical point of view, the reconstruction problem is an inverse problem. In this paper, we formulate the forward and back‐projection problems and we prove the correctness of a particular solution. The usability of the method is demonstrated on a phantom data set.
Electro‐thermal theory of the switching and memory effects in chalcogenide glassy semiconductors
Authors: Tsendin Konstantin
Published: July 2009

A brief review of the most important results of electro‐thermal theory of switching and memory effects is presented. It is shown that this theory is able to explain the large scope of the switching and memory effect experimental findings, including the endurance of modern memory cells.
Two generations of phase‐change memory devices: Differences and common problems
Authors: Popov Anatoly
Published: July 2009

Two generations of phase‐change memory (PCM) devices are analyzed from the point of view of material requirements. The first generation of PCM devices was based on chalcogenide glasses. The lack of sufficient information on the physical and chemical processes within the material that occur during operation of the devices led to poor reliability of the first‐generation PCM integrated circuits (ICs). The second generation of PCM devices uses memory switches based on crystalline chalcogenide alloys. The basic operating mechanisms of the first‐ and second‐generation nonvolatile PCM devices are largely the same. The PCM ICs designers of either generation face the same problems: contradictory requirements toward the phase‐change material, where both low SET and RESET power and high reliability of cells retention are important, the problem of the dispersions of cell characteristics in the SET and RESET states, the problem of the forming process of PCM elements and others. The analysis of the results allows the problems that need solving to be looked at to avoid making the same mistake twice and to create highly reliable PCM devices with acceptable power and geometrical characteristics.
Photoinduced effects in AsSP glasses
Authors: Santagneli Silvia Helena , Messaddeq Sandra Helena , Ribeiro Sidney José Lima , Messaddeq Younès
Published: July 2009

We report the photoinduced effects on the glass composition As2S3 and As29.6P7.4S63 when exposed to UV light. The morphology of the glass surface irradiated at different power densities was investigated by use of optical microscopy and scanning electron microscopy (SEM). A power density dependence on the photoexpansion (PE) and photoablation (PA) is observed. Raman measurement after irradiation shows the formation of AsO bonds in As29.6P7.4S63. Also, the appearance of PO bonds indicate the incorporation of oxygen at the glass surface during the irradiation process.
Leveraging prior quantitative knowledge in guiding pediatric drug development: a case study
Authors: Jadhav Pravin R. , Zhang Jialu , Gobburu Jogarao V. S.
Published: July 2009

The manuscript presents the FDA's focus on leveraging prior knowledge in designing informative pediatric trial through this case study. In developing written request for Drug X, an anti‐hypertensive for immediate blood pressure (BP) control, the sponsor and FDA conducted clinical trial simulations (CTS) to design trial with proper sample size and support the choice of dose range. The objective was to effectively use prior knowledge from adult patients for drug X, pediatric data from Corlopam (approved for a similar indication) trial and general experience in developing anti‐hypertensive agents. Different scenarios governing the exposure response relationship in the pediatric population were simulated to perturb model assumptions. The choice of scenarios was based on the past observation that pediatric population is less responsive and sensitive compared with adults. The conceptual framework presented here should serve as an example on how the industry and FDA scientists can collaborate in designing the pediatric exclusivity trial. Using CTS, inter‐disciplinary scientists with the sponsor and FDA can objectively discuss the choice of dose range, sample size, endpoints and other design elements. These efforts are believed to yield plausible trial design, qrational dosing recommendations and useful labeling information in pediatrics. Published in 2009 by John Wiley & Sons, Ltd.
Evaluation of the antiprotozoal activity of neo‐clerodane type diterpenes from Salvia polystachya against Entamoeba histolytica and Giardia lamblia
Authors: Calzada Fernando , Yepez‐Mulia Lilian , Tapia‐Contreras Amparo , Bautista Elihú , Maldonado Emma , Ortega Alfredo
Published: July 2009

Chia (Salvia polystachya Ort., Lamiaceae) is frequently used in Mexican traditional medicine to treat dysentery. In this study the main neo‐clerodane diterpenes (polystachynes A, B and D, as well as linearolactone) were isolated from the aerial parts of chia, and their antiprotozoal activities toward Entamoeba histolytica and Giardia lamblia trophozoites were evaluated in vitro. Linearolactone was the most potent antiamoebic and antigiardial compound with IC50 values of 22.9 μM for E. histolytica and 28.2 μM for G. lamblia. Polystachynes A, B and D, showed moderate antiprotozoal activity against both protozoans with IC50 values ranging from 117.0 to 160.6 μM for E. histolytica and from 107.5 to 134.7 μM for G. lamblia. These data suggest that linearolactone may play an important role in the antidiarrhoeal activity of S. polystachya. Copyright © 2009 John Wiley & Sons, Ltd.
Screening of binding activity of Streptococcus pneumoniae, Streptococcus agalactiae and Streptococcus suis to berries and juices
Authors: Toivanen Marko , Huttunen Sanna , Duricová Jana , Soininen Pasi , Laatikainen Reino , Loimaranta Vuokko , Haataja Sauli , Finne Jukka , Lapinjoki Seppo , Tikkanen‐Kaukanen Carina
Published: July 2009

Antiadhesion therapy is a promising approach to the fight against pathogens. Antibiotic resistance and the lack of effective vaccines have increased the search for new methods to prevent infectious diseases. Previous studies have shown the antiadhesion activity of juice from cultivated cranberries (Vaccinium macrocarpon Ait.) against bacteria, especially E. coli. In this study, the binding of two streptococcal strains, Streptococcus pneumoniae and Streptococcus agalactiae, to molecular size fractions (FI, FII and FIII, <10 kDa, 10–100 kDa, and >100 kDa, respectively) of berries and berry and fruit juices from 12 plant species were studied using a microtiter well assay. For Streptococcus suis a hemagglutination inhibition assay was used. In general, binding activity was detected especially to wild cranberry (Vaccinium oxycoccos L.) and to other Vaccinium species. S. pneumoniae cells bound most to cranberry juice fraction FI and S. agalactiae cells to cranberry fraction FIII. Hemagglutination induced by S. suis was most effectively inhibited by cranberry fraction FII. NMR spectra of some characteristic active and non‐active fractions were also measured. They indicate that fractions FII and FIII contained proanthocyanidins and/or other phenolic compounds. The results suggest Vaccinium berries as possible sources of antiadhesives against bacterial infections. Copyright © 2009 John Wiley & Sons, Ltd.
Danshen (Salvia miltiorrhiza) extract inhibits proliferation of breast cancer cells via modulation of Akt activity and p27 level
Authors: Yang Wonseok , Ju Ji‐hyun , Jeon Min Jeong , Han Xiangzi , Shin Incheol
Published: July 2009

Danshen is widely used in traditional Chinese medicine, often in combination with other herbs. To check the effect of Danshen on the proliferation of breast cancer cells, Danshen extract was used to treat MCF‐7 and MCF‐7 HER2 cells, the latter of which overexpresses HER2. HER2 is a receptor tyrosine kinase, and is involved in signal transduction pathways leading to tumor cell proliferation. MTT and cell proliferation assays revealed that Danshen strongly inhibited the proliferation of both MCF‐7 vec cells and MCF‐7 HER2 cells. Flow cytometry analyses indicated that Danshen induced cell cycle delay in the G1 phase. HER2 expression was shown to confer resistance to Danshen‐induced inhibition of proliferation and cell cycle delay, suggesting that HER2 is responsible for the resistance to Danshen. Danshen treatment induced the down‐regulation of Akt phosphorylation and an increase in p27 in MCF‐7 vec and MCF‐7 HER2 cells. Nevertheless, MCF‐7 HER2 cells were more resistant to the Danshen‐induced inhibition of Akt phosphorylation and p27 up‐regulation. Copyright © 2009 John Wiley & Sons, Ltd.
Cytotoxic effect of mistletoe (Viscum album L.) extract on Jurkat cells and its interaction with doxorubicin
Authors: Sabová Lucia , Pilátová Martina , Szilagyi Katarína , Sabo Rastislav , Mojžiš Ján
Published: July 2009

Mistletoe preparations are frequently used by cancer patients because of their ability to stimulate the immunity and to improve the quality of life. Moreover mistletoe and its active substances (especially lectins) possess cytotoxic effect on various cancer cell lines. However, only little is known about its interaction with anticancer drugs. Therefore the cytotoxic and apoptosis‐inducing effects of aqueous mistletoe extract (VA) and its interaction with doxorubicin (DOXO) were investigated in Jurkat cells.

The results show that VA extract as well as DOXO exert cytotoxic effects on Jurkat cells in a dose‐dependent manner. Cytotoxicity of DOXO was much stronger (LC50 = 11.68 ng/mL) than that of VA extract (LC50 = 35.67 μg/mL). Their combination led to synergism only at those concentrations that were highly cytotoxic alone. Both substances (alone and in combination) induced DNA fragmentation in Jurkat cells. In conclusion, an aqueous extract prepared from mistletoe tops exerted cytotoxic and apoptosis‐inducing effects on Jurkat cells alone as well as in combination with DOXO. Copyright © 2009 John Wiley & Sons, Ltd.
Theoretical electronic studies of aluminum monobromide and aluminum monoiodide
Authors: Hamade Y. , Taher F. , Monteil Y.
Published: July 2009

By using CASSCF/MRCI methods, theoretical molecular calculations have been performed for 12 electronic states for AlBr molecule and 12 electronic states for AlI molecule in the representation 2s+1Λ (neglecting spin‐orbit effects). Calculated potential energy curves are displayed. Spectroscopic constants including the harmonic vibrational wave number ωe, the electronic energy Te referred to the ground state and the equilibrium internuclear distance Re are predicted for these singlet and triplet electronic states for both AlBr and AlI molecules. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Dynamical properties and thermal rate coefficients for the Na + HF reaction using genetic algorithm
Authors: Antunes Adoniel W. S. , Ferreira Da Cunha Wiliam , Magela E Silva Geraldo , Martins João B. L. , Gargano Ricardo
Published: July 2009

The genetic algorithm optimization technique (GAOT) was used to build a new potential energy surface (PES) to the Na + HF → NaF + H reaction. Quasi‐Classical Trajectories and Transition State Theory methods were used to obtain the dynamical properties and thermal rate coefficients (TRCs), respectively, of this new PES. These features were compared with the dynamical properties and TRCs available in the literature. It was found that the GAOT PES agrees very well with other PESs, in which the maximum difference found is smaller than 1.0 Å2 for the cross‐sections. These results endow the GAOT approach as a method to build PESs of reactive scattering processes. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Theoretical study on the influence of ancillary ligand on the spectroscopic properties and electronic structures of phosphorescent Pt(II) complexes
Authors: Zhang Min , Li Yan , Li Ze‐Sheng , Sun Jia‐Zhong
Published: July 2009

The geometries, energies, and electronic properties of a series of phosphorescent Pt(II) complexes including FPt, CFPt, COFPt, and NFPt have been characterized within density functional theory DFT calculations which can reproduce and rationalize experimental results. The properties of excited‐states of the Pt(II) complexes were characterized by configuration interaction with singles (CIS) method. The ground‐ and excited‐state geometries were optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ levels, respectively. In addition, we also have performed a triplet UB3LYP optimization for complex FPt and compared it with CIS method in the emission properties. The datum (562.52 nm) of emission wavelength for complex FPt, which were computed based on the triplet UB3LYP optimization excited‐state geometry, is not agreement with the experiment value (500 nm). The absorption and phosphorescence wavelengths were computed based on the optimized ground‐ and excited‐state geometries, respectively, by the time‐dependent density functional theory (TD‐DFT) methods. The results revealed that the nature of the substituent at the phenylpyridine ligand can influence the distributions of HOMO and LUMO and their energies. Moreover, the auxiliary ligand pyridyltetrazole can make the molecular structure present a solid geometry. In addition, the charge transport quality has been estimated approximately by the predicted reorganization energy (λ). Our result also indicates that the substitute groups and different auxiliary ligand not only change the nature of transition but also affect the rate and balance of charge transfer. By summarizing the results, we can conclude that the NFPt is good OLED materials with a solid geometry and a balanced charge transfer rate. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
A linear three‐center four electron bonding identity nucleophilic substitution at carbon, boron, and phosphorus. A theoretical study in combination with van't Hoff modeling
Authors: Buck Henk M.
Published: July 2009

We studied various identity nucleophilic substitution reactions based on an SN2 reaction profile. With calculations and experimental geometries concerning the nature of the various complexes indicated as stable, intermediate, and transition state we were able to show the additional value of van't Hoff 's tetrahedron by changing its geometry via a trigonal pyramid into a trigonal bipyramid. The ratio of the apical and the corresponding tetrahedral bond distance is then 1.333. This value has been used in general as a calibration point for the understanding of the (in)stabilities of the complex formation on the SN2 reaction coordinate. The relevance of this approach has been also proved for enzymatic reactions focused on carbon and phosphorus substrates. Furthermore, it could be established that identity proton‐in‐line displacements are fully comparable with the relocation of carbon in a nucleophilic substitution reaction as Cl− + CH3Cl. The significance of this information will afford new insight in the dynamics of a linear three‐center four‐electron complex. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
An ab initio simulation of the UV/visible spectra of N‐benzylideneaniline dyes
Authors: Jacquemin Denis , Laurent Adèle D. , Perpète Eric A. , André Jean‐Marie
Published: July 2009

The structural parameters and the absorption spectra of more than thirty N‐benzylideneaniline dyes have been determined with a theoretical scheme combining the time‐dependent density functional theory and the polarizable continuum model. For the unsubstituted molecule, the PBE0 hybrid nicely reproduces both the measured structural parameters and the absorption spectrum, and we demonstrate that the nature of the two first transitions is reversed compared with azobenzene. For the set of substituted compounds, the average TD‐DFT error (0.19 eV), that can be significantly reduced by a simple statistical treatment, mainly originates in the charge‐transfer states of push–pull derivatives, whereas local transitions are accurately modeled. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Changes in 13C/12C of oil palm leaves to understand carbon use during their passage from heterotrophy to autotrophy
Authors: Lamade Emmanuelle , Setiyo Indra Eko , Girard Sébastien , Ghashghaie Jaleh
Published: July 2009

The carbon isotope composition of leaf bulk organic matter was determined on the tropical tree Elaeis guineensis Jacq. (oil palm) in North Sumatra (Indonesia) to get a better understanding of the changes in carbon metabolism during the passage from heterotrophy to autotrophy of the leaves. Leaf soluble sugar (sucrose, glucose and fructose) contents, stomatal conductance and dark respiration, as well as leaf chlorophyll and nitrogen contents, were also investigated. Different growing stages were sampled from leaf rank −6 to rank 57. The mean values for the δ13C of bulk organic matter were −29.01 ± 0.9‰ for the leaflets during the autotrophic stage, −27.87 ± 1.08‰ for the petioles and −28.17 ± 1.09‰ for the rachises, which are in the range of expected values for a C3 plant. The differences in δ13C among leaf ranks clearly revealed the changes in the origin of the carbon source used for leaf growth. Leaves were 13C‐enriched at ranks below zero (around −27‰). During this period, the ‘spear’ leaves were completely heterotrophic and reserves from storage organs were mobilised for the growth of these young emerging leaves. 13C‐depletion was then observed when the leaf was expanding at rank 1, and there was a continuous decrease during the progressive passage from heterotrophy until reaching full autotrophy. Thereafter, the δ13C remained more or less constant at around −29.5‰. Changes in sugar content and in δ13C related to leaf ranks showed an interesting similarity of the passage from heterotrophy to autotrophy of oil palm leaves to the budburst of some temperate trees or seed germination reported in the literature. Copyright © 2009 John Wiley & Sons, Ltd.
Should baseline be a covariate or dependent variable in analyses of change from baseline in clinical trials?
Authors: Liu Guanghan F. , Lu Kaifeng , Mogg Robin , Mallick Madhuja , Mehrotra Devan V.
Published: July 2009

In randomized clinical trials, a pre‐treatment measurement is often taken at baseline, and post‐treatment effects are measured at several time points post‐baseline, say t=1, …, T. At the end of the trial, it is of interest to assess the treatment effect based on the mean change from baseline at the last time point T. We consider statistical methods for (i) a point estimate and 95 per cent confidence interval for the mean change from baseline at time T for each treatment group, and (ii) a p‐value and 95 per cent confidence interval for the between‐group difference in the mean change from baseline. The manner in which the baseline responses are used in the analysis influences both the accuracy and the efficiency of items (i) and (ii). In this paper, we will consider the ANCOVA approach with change from baseline as a dependent variable and compare that with a constrained longitudinal data analysis (cLDA) model proposed by Liang and Zeger (Sankhya: Indian J. Stat. (Ser B) 2000; 62:134–148), in which the baseline is modeled as a dependent variable in conjunction with the constraint of a common baseline mean across the treatment groups. Some drawbacks of the ANCOVA model and potential advantages of the cLDA approach are discussed and illustrated using numerical simulations. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of the relationship between longitudinal gene expressions and ordered categorical event data
Authors: Rajicic Natasa , Finkelstein Dianne M. , Schoenfeld David A.
Published: July 2009

The NIH project ‘Inflammatory and Host Response to Injury’ (Glue) is being conducted to study the changes in the body over time in response to trauma and burn. Patients are monitored for changes in their clinical status, such as the onset of and recovery from organ failure. Blood samples are drawn over the first days and weeks after the injury to obtain gene expression levels over time. Our goal was to develop a method of selecting genes that differentially expressed in patients who either improved or experienced organ failure. For this, we needed a test for the association between longitudinal gene expressions and the time to the occurrence of ordered categorical outcomes indicating recovery, stable disease, and organ failure. We propose a test for which the relationship between the gene expression and the events is modeled using the cumulative proportional odds model that is a generalization of the pooling repeated observation method. Given the high‐dimensionality of the microarray data, it was necessary to control for the multiplicity of the testing. To control for the false discovery rate (FDR), we applied both a permutational approach as well as Efron's empirical estimation method. We explore our method through simulations and provide the analysis of the multi‐center, longitudinal study of immune response to inflammation and trauma (http://www.gluegrant.org). Copyright © 2009 John Wiley & Sons, Ltd.
Sample sizes for a robust ranking and selection of genes in microarray experiments
Authors: Matsui Shigeyuki , Oura Tomonori
Published: July 2009

The main role of high‐throughput microarrays today is screening of relevant genes from a large pool of candidate genes. For prioritizing genes for subsequent studies, gene ranking based on the strength of the association with the phenotype is a relevant statistical output. In this article, we propose sample size calculations based on gene ranking and selection using the non‐parametric Mann–Whitney–Wilcoxon statistic in microarray experiments. The use of the non‐parametric statistic is expected to be advantageous in robustification in gene ranking for the deviation from normality and for possible scale change by using different platforms such as polymerase chain reaction‐based platforms in subsequent studies in gene expression data. Application to the data set from a clinical study for lymphoma is given. Copyright © 2009 John Wiley & Sons, Ltd.
Long-Term, Stable Differentiation of Human Embryonic Stem Cell-Derived Neural Precursors Grafted into the Adult Mammalian Neostriatum
Authors: Nasonkin Igor , Mahairaki Vasiliki , Xu Leyan , Hatfield Glen , Cummings Brian J. , Eberhart Charles , Ryugo David K. , Maric Dragan , Bar Eli , Koliatsos Vassilis E.
Published: July 2009

Stem cell grafts have been advocated as experimental treatments for neurological diseases by virtue of their ability to offer trophic support for injured neurons and, theoretically, to replace dead neurons. Human embryonic stem cells (HESCs) are a rich source of neural precursors (NPs) for grafting, but have been questioned for their tendency to form tumors. Here we studied the ability of HESC-derived NP grafts optimized for cell number and differentiation stage prior to transplantation, to survive and stably differentiate and integrate in the basal forebrain (neostriatum) of young adult nude rats over long periods of time (6 months). NPs were derived from adherent monolayer cultures of HESCs exposed to noggin. After transplantation, NPs showed a drastic reduction in mitotic activity and an avid differentiation into neurons that projected via major white matter tracts to a variety of forebrain targets. A third of NP-derived neurons expressed the basal forebrain-neostriatal marker dopamine-regulated and cyclic AMP-regulated phosphoprotein. Graft-derived neurons formed mature synapses with host postsynaptic structures, including dendrite shafts and spines. NPs inoculated in white matter tracts showed a tendency toward glial (primarily astrocytic) differentiation, whereas NPs inoculated in the ventricular epithelium persisted as nestin(+) precursors. Our findings demonstrate the long-term ability of noggin-derived human NPs to structurally integrate tumor-free into the mature mammalian forebrain, while maintaining some cell fate plasticity that is strongly influenced by particular central nervous system (CNS) niches.
3D Timelapse Analysis of Muscle Satellite Cell Motility
Authors: Siegel Ashley L. , Atchison Kevin , Fisher Kevin E. , Davis George E. , Cornelison D.D.W.
Published: July 2009

Skeletal muscle repair and regeneration requires the activity of satellite cells, a population of myogenic stem cells scattered throughout the tissue and activated to proliferate and differentiate in response to myotrauma or disease. While it seems likely that satellite cells would need to navigate local muscle tissue to reach damaged areas, relatively little data on such motility exist, and most studies have been with immortalized cell lines. We find that primary satellite cells are significantly more motile than myoblast cell lines, and that adhesion to laminin promotes primary cell motility more than fourfold over other substrates. Using timelapse videomicroscopy to assess satellite cell motility on single living myofibers, we have identified a requirement for the laminin-binding integrin α7β1 in satellite cell motility, as well as a role for hepatocyte growth factor in promoting directional persistence. The extensive migratory behavior of satellite cells resident on muscle fibers suggests caution when determining, based on fixed specimens, whether adjacent cells are daughters from the same mother cell. We also observed more persistent long-term contact between individual satellite cells than has been previously supposed, potential cell-cell attractive and repulsive interactions, and migration between host myofibers. Based on such activity, we assayed for expression of “pathfinding” cues, and found that satellite cells express multiple guidance ligands and receptors. Together, these data suggest that satellite cell migration in vivo may be more extensive than currently thought, and could be regulated by combinations of signals, including adhesive haptotaxis, soluble factors, and guidance cues.
Isolation of Neural Crest Derived Chromaffin Progenitors from Adult Adrenal Medulla
Authors: Chung Kuei-Fang , Sicard Flavie , Vukicevic Vladimir , Hermann Andreas , Storch Alexander , Huttner Wieland B. , Bornstein Stefan R. , Ehrhart-Bornstein Monika
Published: July 2009

Chromaffin cells of the adrenal medulla are neural crest-derived cells of the sympathoadrenal lineage. Unlike the closely-related sympathetic neurons, a subpopulation of proliferation-competent cells exists even in the adult. Here, we describe the isolation, expansion, and in vitro characterization of proliferation-competent progenitor cells from the bovine adrenal medulla. Similar to neurospheres, these cells, when prevented from adherence to the culture dish, grew in spheres, which we named chromospheres. These chromospheres were devoid of mRNA specific for smooth muscle cells (MYH11) or endothelial cells (PECAM1). During sphere formation, markers for differentiated chromaffin cells, such as phenylethanolamine-N-methyl transferase, were downregulated while neural progenitor markers nestin, vimentin, musashi 1, and nerve growth factor receptor, as well as markers of neural crest progenitor cells such as Sox1 and Sox9, were upregulated. Clonal analysis and bromo-2′-deoxyuridine-incorporation analysis demonstrated the self-renewing capacity of chromosphere cells. Differentiation protocols using NGF and BMP4 or dexamethasone induced neuronal or endocrine differentiation, respectively. Electrophysiological analyses of neural cells derived from chromospheres revealed functional properties of mature nerve cells, such as tetrodotoxin-sensitive sodium channels and action potentials. Our study provides evidence that proliferation and differentiation competent chromaffin progenitor cells can be isolated from adult adrenal medulla and that these cells might harbor the potential for the treatment of neurodegenerative diseases, such as Parkinson's disease.
Performance of bolted angle connections in progressive collapse of steel frames
Authors: Pirmoz Akbar
Published: July 2009

This paper is mainly focused on the behaviour of bolted top‐seat angle connections with double web angles, categorized as partially restrained connections, in progressive collapse of semi‐rigid steel frames due to sudden column loss. The main characteristics of this type of loading are declared and the effect of the imposed boundary conditions on the motivated elements is depicted. To study the performance of frame connections under these conditions, refined nonlinear finite element modelling technique is used. The models are created based on the previous experimental studies and their accuracy is examined through a comparison to the results of these tests. New models are created under conditions of the progressive collapse and the behaviour of the connections is studied. The study showed that due to the applied boundary conditions, the connections behave stiffer and show a higher moment capacity. Based on the results of the numerical models, equations are presented to estimate the moment‐rotation response of the studied connections under progressive collapse conditions based on the beam and connection mechanical and geometrical properties and the connection rotation. Copyright © 2009 John Wiley & Sons, Ltd.
A case study of the structural responses of a tall building in Singapore subjected to close‐in detonations
Authors: Li Bing , Pan Tso‐Chien , Nair Anand
Published: July 2009

The response of tall buildings has been a major concern in metropolitan cities, especially with the recent surge in extreme activities targeted at structures with viable commercial values. This paper discusses a study carried out on the structural behaviour of a 2D frame, modelled to represent a tall building with ABAQUS. The model frame was subjected to a charge of the equivalent weight of 1 ton of TNT but placed at two varying cases of 5 and 10‐m standoff distances. Plane‐strain elements that incorporate the feature of material nonlinearity were utilized to model the structural components of the building and the simulated blast overpressures were obtained from the CONWEP software. The effects of large deformations of beams and columns corresponding to the short time loading duration depicted by the explosions were analysed from a local perspective. The extent of the damage is based on a local index defined as the ratio of curvatures. These local indices are consequently used to determine the possibility of disproportionate collapse of the frame from a global perspective. Finally, the provision of more ductile structural detailing is recommended to enhance the structural integrity of the building, increasing its resilience against blast attacks. Copyright © 2009 John Wiley & Sons, Ltd.
Male gender as a favorable prognostic factor in pregnancies with enlarged nuchal translucency
Authors: Timmerman E. , Pajkrt E. , Bilardo C. M.
Published: July 2009

Objective

The aim of this study was to investigate the influence of fetal gender on pregnancy outcome in fetuses with enlarged nuchal translucency (NT).

Methods

Pregnancy outcomes of all women who underwent an NT measurement at our institution between January 2000 and November 2007 were retrospectively reviewed. Separate analyses were performed for fetuses with normal and with enlarged (≥ 95th percentile) NT.

Results

A normal NT was measured in 3637 males (51.4%) and 3435 females (48.6%). Of the fetuses with enlarged NT 365 were males (57.4%) and 271 females (42.6%) (P = 0.001). In this group a normal pregnancy outcome—of those pregnancies for which the outcome was known—was registered for 187/332 (56.3%) of the male fetuses and 98/249 (39.4%) of the female fetuses (P < 0.001; relative risk (RR) for adverse outcome for male gender, 0.72). Eighty percent of the chromosomally normal male fetuses with an enlarged NT had an uneventful pregnancy outcome; this increased to 90% when only the male fetuses with NT measurements ≥ 95th percentile and < 99th percentile and normal karyotype were considered (RR for adverse outcome for male gender, 0.47).

Conclusion

In a population of fetuses with enlarged NT there are significantly more males. Male fetuses with enlarged NT and normal chromosomes have an almost two‐fold greater chance of a favorable outcome than females. We believe that a minimal degree of NT enlargement in male fetuses without genetic or structural anomalies may be interpreted as a feature of accelerated growth or, alternatively, as a maturational delay of the cardiovascular system more common in males, leading to moderately increased nuchal fluid accumulation. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Effect of mifepristone on the corpus luteum in early pregnancy
Authors: Niinimäki M. , Ruokonen A. , Tapanainen J. S. , Järvelä I. Y.
Published: July 2009

Objective

The antiprogestin mifepristone is widely used for medical termination of pregnancy (TOP). Previous studies have suggested that the mechanism of mifepristone is based on its action in the endometrium and myometrium. The aim of this study was to evaluate the possible effects of mifepristone on corpus luteum activity.

Methods

This was a prospective, longitudinal controlled study to which 20 patients undergoing medical TOP (study group) and 20 patients with normal ongoing pregnancy (control group) were recruited. Medical TOP was induced with 200 mg of mifepristone followed by 0.8 mg of misoprostol 2 days later. Three‐dimensional ultrasound examinations and hormone assays (progesterone, human chorionic gonadotropin, and 17‐hydroxyprogesterone) were performed in both groups on the day of, and 2 days after, administration of mifepristone. Total volume (vascularized + non‐vascularized) of the dominant (containing corpus luteum) and non‐dominant ovary and serum hormone levels were measured.

Results

After administration of mifepristone, a decrease in serum progesterone levels was observed with a simultaneous decrease in the non‐vascularized volume of the dominant ovary in the study group. No such changes were observed in the control group.

Conclusions

The observations indicate that, in addition to trophoblastic tissue, the corpus luteum is also the target of mifepristone. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Agreement between umbilical vein volume blood flow measurements obtained at the intra‐abdominal portion and free loop of the umbilical cord
Authors: Flo K. , Wilsgaard T. , Acharya G.
Published: July 2009

Objective

The umbilical vein (UV) is a single vessel and theoretically the volume of blood flowing through it should be equal whether it is measured at the intra‐abdominal portion (IA) or a free loop of the umbilical cord (FL). However, the reported values vary considerably depending on the technique and site of measurement. Our objective was to investigate the correlation and agreement between UV volume blood flows (Quv) measured at the IA and FL.

Methods

Blood flow velocities and inner diameter of the UV were measured cross‐sectionally at the IA and FL in 131 pregnant women at 22–24 weeks' gestation, and in 53 of them longitudinally at 4‐weekly intervals until delivery. For each sampling site, the Quv was calculated as: 0.5 × time‐averaged maximum velocity × π × (UV diameter/2)2.

Results

The mean Quv measured at the IA (61.5 ± 23.3 mL/min) and FL (60.7 ± 17.6 mL/min) cross‐sectionally in 131 fetuses at 22–24 weeks of gestation were similar, but the bivariate correlation between them was not strong (r = 0.38; P < 0.0001) and the intraclass correlation coefficient (ICC) was 0.37 (95% CI, 0.21–0.51). When the agreement between 131 pairs of Quv measurements was tested with Bland–Altman analysis, the mean of the ratio IA‐Quv/FL‐Quv was found to be 1.05 (i.e. IA‐Quv exceeded FL‐Quv on average by 5%) with 95% limits of agreement of 0.31–1.78. In the longitudinal analysis of 232 pairs of Quv measurements from 53 fetuses at 22–40 weeks, the mean Quv obtained at the IA and FL were similar, i.e. 164 ± 87 (range, 25–484) mL/min vs. 159 ± 82 (range, 30–470) mL/min, and the correlation between them, assessed after grouping the observations in five different gestational age groups of 4‐week intervals, was slightly better (r = 0.45–0.62; P < 0.0001). The ICC for the Quv measurements obtained at the two sites ranged from 0.38 to 0.54. The mean of the ratio IA‐Quv/FL‐Quv was 1.07 (i.e. IA‐Quv exceeded FL‐Quv on average by 7%), with 95% limits of agreement of 0.39–1.75.

Conclusion

Average Quv measured at the IA and FL was similar, but the agreement between individual pairs of measurements was not good enough to be able to use them interchangeably. Therefore, any clinical application of Quv measurement would require standardization of the technique, strict adherence to methodology and use of appropriate reference ranges for it to be useful. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Preparation and Properties of Sodium Dimethyldithioarsinate Dihydrate, Me2AsS2Na·2H2O, and Palladium(II) Dimethyldithioarsinate, (Me2AsS2)2Pd
Authors: Ioannou Panayiotis V. , Vachliotis Dimitris G. , Nastopoulos Vassilios , Tasiopoulos Anastasios J.
Published: July 2009

Palladium(II) acetate in non‐deaerated chloroform splits Bunsen’s cacodyl disulfide, Me2As(S)–S–AsMe2, giving the complex (Me2AsS2)2Pd, slightly soluble in chloroform, and the arsonium ion Me2As:+. However, after a few minutes the complex reacted giving Me2As(S)–O–As(S)Me2 and other, so far unidentified compounds. Therefore, the complex (Me2AsS2)2Pd was prepared from sodium dimethyldithioarsinate dihydrate, Me2AsS2Na·2H2O, and palladium(II) acetate. (Me2AsS2)2Pd reacts with PdII and Ph3P in a different way compared to other (Me2AsS2)xM (M = heavy metal cation) and (Me2PS2)2Pd. The reaction of equimolar quantities of Me2AsS2Na·2H2O and Ph3P under argon involved four consecutive reactions with Me2As–O–AsMe2 and Me2AsS2Na as the final products. The salt Me2AsS2Na·2H2O has been structurally characterized: triclinic, P\bar{1}, a = 6.0285(2) Å, b = 6.5552(2) Å, c = 12.1480(4) Å, α = 98.282(2)ό, β = 93.994(3)ό, γ = 115.951(3)ό, V = 422.38(3) Å3, Z = 2, R1 = 0.0207, wR2 = 0.0414.
Living donor pancreas transplantation in Japan
Authors: Kenmochi Takashi , Asano Takehide , Maruyama Michihiro , Saigo Kenichi , Akutsu Naotake , Iwashita Chikara , Ohtsuki Kazunori , Suzuki Akiko , Miyazaki Mariko
Published: July 2009

Background/purpose

Living‐donor pancreas transplants (LDPs) were introduced at Chiba‐East National Hospital in 2004, and 12 LDPs have been performed at this institution to date. Based on the outcome of these 12 LDPs, the efficacy and safety of LDPs are herein discussed.

Methods

Twelve diabetic patients underwent LDPs; ten had simultaneous pancreas and kidney transplants from living donors, one had pancreas transplant after a kidney transplant from a living donor, and one had a pancreas transplant alone from a living donor. The donors were parents or brothers and the ABO blood types were incompatible in three LDPs. The procedures for the donor and recipient operations were performed according to the technique established by the University of Minnesota. Bladder drainage was used in 11 recipients and enteric drainage was used in one patient. Tacrolimus, basiliximab, mycophenolate mofetil, and prednisone were used for induction and immunosuppressive treatment. A splenectomy, double‐filtered plasmapheresis, and plasma exchange were added in the ABO‐incompatible LDPs.

Results

No complications were observed in the donors during hospitalization. The 1‐year survivals of the patients, kidney grafts, and pancreas grafts were 100, 100, and 100%, respectively. The 3‐year survivals were 91.7, 90, and 91.7%, respectively. Three patients developed leakage of pancreatic juice and one patient required a surgical procedure. Cytomegalovirus antigenemia was detected in five patients (42%).

Conclusions

Based on the excellent outcome of the LDPs at this institution, LDPs is therefore expected to become a promising option for the treatment of patients with severe diabetes.
A revaluation of lake‐phosphorus loading models using a Bayesian hierarchical framework
Authors: Cheng Vincent , Arhonditsis George B. , Brett Michael T.
Published: July 2009

We revisit the phosphorus‐retention and nutrient‐loading models in limnology using a Bayesian hierarchical framework. This methodological tool relaxes a basic assumption of regression models fitted to data sets consisting of observations from multiple systems, i.e., the systems are assumed to be identical in behavior, and therefore the models have a single common set of parameters for all systems. Under the hierarchical structure, the models are dissected into levels (hierarchies) that explicitly account for the role of significant sources of variability (e.g., morphometry, mixing regime, geographical location, land‐use patterns, trophic status), thereby allowing for intersystem parameter differences. Thus, the proposed approach is a compromise between site‐specific (where limited local data is a problem) and globally common (where heterogeneous systems in wide geographical areas are assumed to be identical) parameter estimates. In this study, we used critical values of the mean lake depth and the hydraulic residence time (τw = 2.6 years) to specify the hierarchical levels of the models. Our analysis demonstrates that the hierarchical configuration led to an improvement of the performance of six out of the seven hypothesized relationships used to predict lake‐phosphorus concentrations. We also highlight the differences in the posterior moments of the group‐specific parameter distributions, although the inference regarding the importance of different predictors (e.g., inflow‐weighted total phosphorus input concentration, and hydraulic retention time) of lake phosphorus or the relative predictability of the models examined are not markedly different from an earlier study by Brett and Benjamin. The best fit to the observed data was obtained by the model that considers the first‐order rate coefficient for total phosphorus loss from the lake as an inverse function of the lake hydraulic retention time. Finally, our analysis also demonstrates how the Bayesian hierarchical framework can be used for assessing the exceedance frequency and confidence of compliance of water‐quality standards. We conclude that the proposed methodological framework will be very useful in the policy‐making process and can optimize environmental management actions in space and time.
Predictive factors of successful pregnancy after assisted reproductive technology in women aged 40 years and older
Authors: Fujimoto Akihisa , Fujiwara Toshihiro , Oishi Hajime , Hirata Tetsuya , Yano Tetsu , Taketani Yuji
Published: July 2009

Purpose

This study aimed to investigate the factors that predict successful pregnancy (live birth) in assisted reproductive technology (ART) for infertile women aged 40 and older.

Methods

Patients who underwent first ART treatments at the age of 40 and older at our institution were enrolled. Several factors which can be evaluated before the first treatments were retrospectively compared among those patients who did and did not achieve live birth.

Results

Nineteen of 119 patients delivered healthy babies. There was no significant difference of live‐birth rate among age groups of 40, 41 and 42. No women who underwent the first treatment at age 43 or older achieved live birth. In the successful group, significantly more women held FSH levels under 12 mIU/ml and had regular menstrual cycles (26–32 days) than unsuccessful women of the same age group. In addition, significantly fewer women in the successful group had prior ovarian surgery.

Conclusions

Our results show that low FSH levels, regular menstrual cycles and absence of prior ovarian surgery were related to high live‐birth rates and they are good prognostic factors in patients between 40 and 42 years of age. On the other hand, none of these parameters were correlated with success in women aged 43 and older.
Autoantibodies and coagulation in reproductive medicine
Authors: Matsubayashi Hidehiko
Published: July 2009

Management of recurrent pregnancy loss (RPL) is considered to be difficult, in part because of cunfusion between autoantibodies and coagulation disorders. Autoantibodies and coagulation are related; two groups of multicenter studies concerning autoantibodies and coagulation reported that factor XII deficiency, hypofibrinolysis, anti‐phosphatidylethanolamine (aPE), anti‐beta2‐glycoprotein I, anti‐annexin A5, and lupus anticoagulant (LA) were found to be frequent risk factors in RPL women. Therefore, discrimination of autoantibodies and coagulation is important in understanding RPL well. We propose three types of pathways regarding reproduction, which are different and independent: (1) Negatively charged‐phospholipid related antibodies (anti‐phosphatidylserine; aPS, anti‐cardiolipin; aCL, lupus anticoagulant; LA, anti‐annexin A5; aANX), (2) factor XII–aPE–fibrinolysis: suppression of fibrinolysis, (3) protein C–protein S–factor V: loss of inactivation against activated factor V. Women with RPL and infertility showed similar findings in terms of the above clinical tests. Available data, however, is not enough to conclude whether these are pathogenic to infertile women.
Postcolonial partnerships: deep sea research, media coverage and (inter)national narratives on the Galathea Deep Sea Expedition from 1950 to 1952
Authors: NIELSEN KRISTIAN HVIDTFELT
Published: July 2009

The Danish Galathea Deep Sea Expedition between 1950 and 1952 combined scientific and official objectives with the production of national and international narratives distributed through the daily press and other media. Dispatched by the Danish government on a newly acquired naval ship, the expedition undertook groundbreaking deep sea research while also devoting efforts to showing the flag, public communication of science, and international cooperation. The expedition was conceived after the war as a way in which to rehabilitate Denmark's reputation internationally and to rebuild national pride. To this end, the expedition included an onboard press section reporting the expedition to the Danish public and to an international audience. The press section mediated the favourable, post-war and postcolonial image of Denmark as an internationalist, scientific, modernizing and civilizing nation for which the expedition planners and many others were hoping. The expedition, therefore, was highly relevant to, indeed fed on, the emerging internationalist agenda in Denmark's foreign policy. Bringing out these aspects of the historical context of the expedition, this paper adds important perspectives to our knowledge about the expedition in particular and, more generally, about scientific exploration in the immediate post-war and postcolonial period.