bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated transit and land use intentions: Alternate scenarios with PRT and shuttle/loop technologies
Authors: Warren Roxanne
Published: January 2010

Ecological impacts of urban sprawl on the land, as well as forces that engender sprawl are outlined. Long‐range land use priorities for more compact, transit‐oriented development (TOD) are seen as ecological imperatives. While Personal Rapid Transit (PRT) could solve some congestion, it does not address these priorities. Several assumptions that underlie the PRT concept, particularly the premise that denser land use is per se socially undesirable, are challenged in terms of historical precedent. Rather, the explosive scale of ubiquitous motoring is seen as the key component of today's resistance to dense development. With peripheral parking and medium‐capacity AGT links to regional transportation networks, new TOD could be redefined as pedestrian‐zoned and richly landscaped urban neighborhoods; this would help resolve essential traffic and environmental barriers to its realization. The simpler automated shuttle and loop technologies are seen as more compact and potentially affordable for this purpose. Steps that could help open the way toward realization of such development are discussed.
Dense network traffic models, Travel time reliability and traffic management. I: General introduction
Authors: Taylor Michael A P
Published: January 2010

This paper is the first of a pair of papers discussing two main themes concerning dense network modelling. These themes are: (1) the changing nature of traffic management technology and the underlying objectives behind traffic management practice, and (2) the use of measures of network reliability in models, especially as an element of the evaluation of alternative network configurations. This paper considers the role and function of dense network models, and their relationships with other transport network models on the basis of the hierarchical view of models. It then explores the peculiar characteristics of dense network models and provides examples of typical models. Changing needs for modelling capabilities, in terms of the evolution of traffic management technology and practice are discussed, pointing the way to future model developments. The companion paper develops the second theme through the definition and application of a set of network reliability indices that may be applied to different trip movements.
Dense network traffic models, travel time reliability and traffic management. Ii: Application to network reliability
Authors: Taylor Michael A P
Published: January 2010

This paper is the second of a pair of papers discussing two main themes concerning dense network modelling. These themes are: (1) the changing nature of traffic management technology and the underlying objectives behind traffic management practice, and (2) the use of measures of network reliability in models, especially as an element of the evaluation of alternative network configurations. This paper develops and applies the second theme, the use of network reliability concepts in the evaluation of traffic networks, through consideration of variations in travel times, distinction between local street and arterial road networks, and the definition and application of a set of reliability indices that may be used to study different trip movements in a network. It indicates how these indices may be used in appraising different traffic management plans for a dense network of local streets and arterial roads, using a case study application.
Estimation of link performance functions from incomplete flow data
Authors: Hazelton Martin L. , Pueschel John
Published: January 2010

Despite the pivotal importance of link performance functions to models of transport systems, relatively little work has been done on practical aspects of estimating these functions from observed data. Furthermore it is difficult to find any examples in the literature of estimated urban link performance functions faithfully reproducing theoretical travel time‐flow relationships. One reason for the paucity of research in this area is the difficulty and expense of obtaining the requisite data. The increase in automatic collection of traffic flow data goes part way to resolving this problem, but matching such flows to manually recorded travel times can present considerable statistical difficulties in the estimation procedure. This paper considers the estimation of link performance functions from a combination of automatically recorded traffic counts and travel collected by hand, using a non‐standard statistical methodology. The study is motivated by a set of data of precisely this type, from the UK city of Leicester.
Transport economics: A personal view
Authors: Hensher David A.
Published: January 2010

The field of transportation attracts individuals from diverse backgrounds, seeking to make contributions to policy, planning, operations and strategy. Economists are one of the more visible subsets of players, who bring a specific focus to the transport problem. The key theme of this paper is economic efficiency and ways that transport economics seeks to achieve efficient outcomes in the presence of markets and institutions that to varying degrees distort the potential to fulfil this primary goal. We review some of the recent contributions to the literatures on institutional and market reform, travel choice and demand. As we enter the next century, there is a sense of promoting ‘back to basics’ (and redefinition of what skills transport specialists will require) in seeking a better understanding of the role of markets and institutions in guiding the destiny of the transport sector.
New waves in transportation in North‐Eastern Europe
Authors: Himanen Veli
Published: January 2010

North‐Eastern Europe is a peripheral area around the Baltic Sea. In some parts i.e. Scandinavia high living standards including developed transport systems exist when at the same time rapid changes in the way of living in other parts ‐ Poland, the Baltic Countries and Russia ‐ are ongoing. Transport policies in the European Union are caught between demands for improved mobility and the concern on the environmental protection. In the former socialist countries the environmental issues are subdued by the demands for efficient transport. A fixed road and rail connection between Denmark and Sweden will change the transport geography of the western part of the area. Also the integration of the Baltic States and Poland to the Union will inside a few years change the economic and by that way also transport structure. After a short presentation of the geography and history the current European transport landscape will be described and current transport policies reviewed. Then some topics on the major changes during the last decennia as well as future studies will be presented. The paper draws heavily from the research projects ‐ SAMI, START and STEMM ‐ financed by the European Commission DGVII.
Transport planning for urban areas: A retrospective look and future prospects
Authors: Meyer Michael D.
Published: January 2010

This paper examines the evolution of urban transport planning since the 1960′s, identifies the key trends that have influenced such planning, describes the current state of urban transport planning, and speculates on the important characteristics that will influence urban transport planning over the next several decades. Fifteen planning conferences since 1957 are reviewed to show the changing perspectives on planning from the professional community. Ten areas are identified that will provide special challenge to future transport planners—demographic changes, the importance of economic production and market forces for transport system performance, multimodal perspectives for transport planning, adopting an operations focus, an important role for technology, developing a sense of community, laying the groundwork for pricing, integrating transport decision making with growth management, transport planning within a sustainability framework, and providing greater accountability of the decision making and planning processes.
Modelling the provision of transport with planned or market‐determined public transport services
Authors: Allsop Richard E.
Published: January 2010

Implications of the difference between planned and market‐determined public transport services for the modelling of the transport system and its use are examined. In the former case, the task for government seeking to optimise performance of the transport system has a standard bi‐level form, but in the latter case, the lower‐level problem in the bi‐level formulation is to determine mutually consistent solutions to a pair of optimisation problems. The relevance of the mutually consistent solution in this context is contrasted with its sometimes misleading role in the context of optimisation of urban traffic signal control.
Operational objective functions in designing public transport routes
Authors: Ceder Avishai
Published: January 2010

This work proposes a framework for the construction of the operational objective functions of the public transport network design problem. This framework takes into account the passengers, operator and community interests. The methodology presented combines the philosophy of the mathematical programming approaches with decision‐making techniques, so as to allow the user to select from a number of alternatives. The nature of the overall formulation is nonlinear and mixed integer programming.
A system dynamics approach to land use/transportation system performance modeling Part I: Methodology
Authors: Haghani Ali , Lee Sang Y. , Byun Joon H.
Published: January 2010

This paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD.

In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance.

While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited due to data availability, the results indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling.
Network equilibrium for congested multi‐mode networks with elastic demand
Authors: Wu Z. X. , Lam William H. K.
Published: January 2010

This paper proposes an elastic demand network equilibrium model for networks with transit and walking modes. In Hong Kong, the multi‐mode transit system services over 90% of the total journeys and the demand on it is continuously increasing. Transit and walking modes are related to each other as transit passengers have to walk to and from transit stops. In this paper, the multi‐mode elastic‐demand network equilibrium problem is formulated as a variational inequality problem where the combined mode and route choices are modeled in a hierarchical logit structures and the total travel demand for each origin‐destination pair is explicitly given by an elastic demand function. In addition, the capacity constraint for transit vehicles and the effects of bi‐directional flows on walkways are considered in the proposed model. All these congestion effects are taken into account for modeling the travel choices. A solution algorithm is developed to solve the multi‐mode elastic‐demand network equilibrium model. It is based on a Block Gauss‐Seidel decomposition approach coupled with the method of successive averages. A numerical example is used to illustrate the application of the proposed model and solution algorithm.
Eukaryotic cold shock domain proteins: highly versatile regulators of gene expression
Authors: Mihailovich Marija , Militti Cristina , Gabaldón Toni , Gebauer Fátima
Published: January 2010

Cold shock domain (CSD)‐containing proteins have been found in all three domains of life and function in a variety of processes that are related, for the most part, to post‐transcriptional gene regulation. The CSD is an ancient β‐barrel fold that serves to bind nucleic acids. The CSD is structurally and functionally similar to the S1 domain, a fold with otherwise unrelated primary sequence. The flexibility of the CSD/S1 domain for RNA recognition confers an enormous functional versatility to the proteins that contain them. This review summarizes the current knowledge on eukaryotic CSD/S1 domain‐containing proteins with a special emphasis on UNR (upstream of N‐ras), a member of this family with multiple copies of the CSD.
Phyto‐bioconversion of hard coal in the Cynodon dactylon/coal rhizosphere
Authors: Igbinigie Eric E. , Mutambanengwe Cecil C. Z. , Rose Peter D.
Published: January 2010

Fundamental processes involved in the microbial degradation of coal and its derivatives have been well documented. A mutualistic interaction between plant roots and certain microorganisms to aid growth of plants such as Cynodon dactylon (Bermuda grass) on hard coal dumps has recently been suggested. In the present study coal bioconversion activity of nonmycorrhizal fungi was investigated in the C. dactylon/coal rhizosphere. Fungal growth on 2% Duff‐agar, gutation formation on nitric acid treated coal and submerged culture activity in nitrogen‐rich and ‐deficient broth formed part of the screening and selection of the fungi. The selected fungal isolates were confirmed to be found in pristine C. dactylon/coal rhizosphere. To simulate bioconversion, a fungal aliquot of this rhizosphere was used as inoculum for a Perfusate fixed bed bioreactor, packed with coal. The results demonstrate an enhanced coal bioconversion facilitated by low molecular weight organics and the bioconversion of coal may be initiated by an introduction of nitrogen moieties to the coal substrate. These findings suggest a phyto‐bioconversion of hard coal involving plant and microbes occurring in the rhizosphere to promote the growth of C. dactylon. An understanding of this relationship can serve as a benchmark for coal dumps rehabilitation as well as for the industrial scale bioprocessing of hard coal.
Exploiting biocatalysis in peptide self‐assembly
Authors: Williams Richard J. , Mart Robert J. , Ulijn Rein V.
Published: January 2010

This review article covers recent developments in the use of enzyme‐catalyzed reactions to control molecular self‐assembly (SA), an area that merges the advantages of biocatalysis with soft materials self‐assembly. This approach is attractive because it combines biological (chemo‐, regio‐, and enantio‐) selectivity with the versatility of bottom up nanofabrication through dynamic SA. We define enzyme‐assisted SA (e‐SA) as the production of molecular building blocks from nonassembling precursors via enzymatic catalysis, where molecular building blocks form ordered structures via noncovalent interactions. The molecular design of SA precursors is discussed in terms of three key components related to (i) enzyme recognition, (ii) molecular switching mechanisms, and (iii) supramolecular interactions that underpin SA. This is followed by a discussion of a number of unique features of these systems, including spatiotemporal control of nucleation and structure growth, the possibility of controlling mechanical properties and the defect correcting and component selecting capabilities of systems that operate under thermodynamic control. Applications in biomedicine (biosensing, controlled release, matrices for wound healing, controlling cell fate by gelation) and bio(nano)technology (biocatalysts immobilization, nanofabrication, templating, and intracellular imaging) are discussed. Overall, e‐SA allows for unprecedented control over SA processes and provides a step forward toward production of nanostructures of higher complexity and with fewer defects as desired for next generation nanomaterials. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94:107–117, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Wall effects in continuous microfluidic magneto‐affinity cell separation
Authors: Wu Liqun , Zhang Yong , Palaniapan Moorthi , Roy Partha
Published: January 2010

Continuous microfluidic magneto‐affinity cell separator combines unique microscale flow phenomenon with advantageous nanobead properties, to isolate cells with high specificity. Owing to the comparable size of the cell–bead complexes and the microchannels, the walls of the microchannel exert a strong influence on the separation of cells by this method. We present a theoretical and experimental study that provides a quantitative description of hydrodynamic wall interactions and wall rolling velocity of cells. A transient convection model describes the transport of cells in two‐phase microfluidic flow under the influence of an external magnetic field. Transport of cells along the microchannel walls is also considered via an additional equation. Results show the variation of cell flux in the fluid phases and the wall as a function of a dimensionless parameter arising in the equations. Our results suggest that conditions may be optimized to maximize cell separation while minimizing contact with the wall surfaces. Experimentally measured cell rolling velocities on the wall indicate the presence of other near‐wall forces in addition to fluid shear forces. Separation of a human colon carcinoma cell line from a mixture of red blood cells, with folic acid conjugated 1 µm and 200 nm beads, is reported. Biotechnol. Bioeng. 2010; 106: 68–75. © 2010 Wiley Periodicals, Inc.
Exploiting cell‐free systems: Implementation and debugging of a system of biotransformations
Authors: Bujara Matthias , Schümperli Michael , Billerbeck Sonja , Heinemann Matthias , Panke Sven
Published: January 2010

The orchestration of a multitude of enzyme catalysts allows cells to carry out complex and thermodynamically unfavorable chemical conversions. In an effort to recruit these advantages for in vitro biotransformations, we have assembled a 10‐step catalytic system—a system of biotransformations (SBT)—for the synthesis of unnatural monosaccharides based on the versatile building block dihydroxyacetone phosphate (DHAP). To facilitate the assembly of such a network, we have insulated a production pathway from Escherichia coli's central carbon metabolism. This pathway consists of the endogenous glycolysis without triose‐phosphate isomerase to enable accumulation of DHAP and was completed with lactate dehydrogenase to regenerate NAD+. It could be readily extended for the synthesis of unnatural sugar molecules, such as the unnatural monosaccharide phosphate 5,6,7‐trideoxy‐D‐threo‐heptulose‐1‐phosphate from DHAP and butanal. Insulation required in particular inactivation of the amn gene encoding the AMP nucleosidase, which otherwise led to glucose‐independent DHAP production from adenosine phosphates. The work demonstrates that a sufficiently insulated in vitro multi‐step enzymatic system can be readily assembled from central carbon metabolism pathways. Biotechnol. Bioeng. 2010; 106: 376–389. © 2010 Wiley Periodicals, Inc.
Parents' knowledge, attitudes and practices about preventing child sexual abuse: a literature review
Authors: Babatsikos Georgia
Published: January 2010

Increased concern about high rates of child sexual abuse has led to the demand for more prevention programmes, particularly those aimed at parents. Research on how parents manage and reduce the risk of child sexual abuse can help plan programmes. This literature review explores published research on the knowledge, attitudes and practices of parents on the risk and prevention of child sexual abuse and identifies gaps and needs for further research. The majority of studies reviewed originated in North America and Asia, were quantitative, surveyed mainly mothers and were more than ten years old. Recommendations are made for more current and country specific research, further research to gain a deeper understanding of how parents manage the risk of child sexual abuse, more comprehensive research covering a range of knowledge, attitude and practice variables, and greater inclusion of fathers in research. Copyright © 2009 John Wiley & Sons, Ltd.
Casearin X, Its Degradation Product and Other Clerodane Diterpenes from Leaves of Casearia sylvestris: Evaluation of Cytotoxicity against Normal and Tumor Human Cells
Authors: Gonzaga dos Santos André , Pinheiro Ferreira Paulo Michel , Magela Vieira Júnior Gerardo , Perez Carla Cristina , Gomes Tininis Aristeu , Silva Geraldo Humberto , da Silva Bolzani Vanderlan , Veras Costa‐Lotufo Letícia , do Ó Pessoa Cláudia , Cavalheiro Alberto José
Published: January 2010

An EtOH extract of the leaves of Casearia sylvestris afforded new clerodane diterpene, casearin X, together with the known compounds casearins B, D, L, and O, and caseargrewiin F. Casearin X degraded to the corresponding dialdehyde when stored in CDCl3. The diterpenes isolated were cytotoxic to human cancer cell lines, with caseargrewiin F being the most active and the new clerodane, casearin X, the second active compound with IC50 values comparable to the positive control doxorubicin. All isolated diterpenes showed lower activities against normal human cells than against cancer cell lines, which might indicate a possible selective action on cancer cells. Casearin X dialdehyde was not cytotoxic to cancer cells indicating that the occurrence of these CO groups at C(18) and C(19) is incompatible with the cytotoxic activity.
Chemical Composition and Antibacterial Activity of Essential Oils from Different Parts of Litsea cubeba
Authors: Wang Hongwu , Liu Yanqing
Published: January 2010

The composition of the essential oils obtained by hydrodistillation of different parts of Litsea cubeba, including roots, stems, leaves, alabastra (flower buds), flowers, and fruits, were investigated by GC (RI) and GC/MS. The antimicrobial activity of the oils was assessed with disc diffusion and microbroth dilution assays. The results showed large variations in the composition among the different oils. The major components in the oils from roots and fruits, from stems, leaves, and alabastra, and from flowers were citral B (neral), β‐phellandrene, and β‐terpinene, respectively. The inhibition zone (DD) and MIC values for the bacterial strains tested, which were all sensitive to the essential oil of L. cubeba, were in the range of 10.1–35.0 mm and 100–1000 μg/ml, respectively. Hence, the oils of the various parts showed moderate activity against the tested bacteria. This investigation showed that the antibacterial activity of L. cubeba was attributed to the essential oils, thus they can be a potential medicinal resource.
Feasibility and applicability of computer‐assisted myocardial blush quantification after primary percutaneous coronary intervention for ST‐segment elevation myocardial infarction
Authors: Haeck Joost D.E. , Gu Youlan L. , Vogelzang Mathijs , Bilodeau Luc , Krucoff Mitchell W. , Tijssen Jan G.P. , De Winter Robbert J. , Zijlstra Felix , Koch Karel T.
Published: January 2010

Objectives: The aim of the study was to evaluate whether the “Quantitative Blush Evaluator” (QuBE) score is associated with measures of myocardial reperfusion in patients with ST‐segment elevation myocardial infarction (STEMI) treated in two hospitals with 24/7 coronary intervention facilities. Background: QuBE is an open source computer program to quantify myocardial perfusion. Although QuBE has shown to be practical and feasible in the patients enrolled in the Thrombus Aspiration during Percutaneous Coronary Intervention in Acute Myocardial Infarction Study (TAPAS), QuBE has not yet been verified on reperfusion outcomes of primary percutaneous coronary intervention (PCI) patients treated in other catheterization laboratories. Methods: Core lab adjudicated angiographic outcomes and QuBE values were assessed on angiograms of patients who were enrolled in the PRoximal Embolic Protection in Acute myocardial infarction and Resolution of ST‐Elevation (PREPARE) trial. ST‐segment resolution immediately after PCI measured by continuous ST Holter monitoring was calculated by a blinded core lab. Results: The QuBE score could be assessed on 229 of the 284 angiograms (81%) and was significantly associated with visually assessed myocardial blush grade (P < 0.0001). Patients with improved postprocedural Thrombolysis in Myocardial Infarction‐graded flow, myocardial blush grade, ST‐segment resolution immediately after PCI, or a small infarct size measured by peak CK‐MB had a significant better QuBE score. Conclusions: QuBE is feasible and applicable at angiograms of patients with STEMI recorded at other catheterization laboratories and is associated with measures of myocardial reperfusion. © 2010 Wiley‐Liss, Inc.
Reaction Monitoring of Heterogeneously Catalyzed Hydrogenation of Imines by Coupled ATR‐FTIR, UV/Vis, and Raman Spectroscopy
Authors: Knöpke Leif R. , Nemati Navid , Köckritz Angela , Brückner Angelika , Bentrup Ursula
Published: January 2010

Coupled ATR‐FTIR, UV/Vis, and Raman spectroscopy has been introduced for the monitoring of liquid phase hydrogenation reactions under elevated H2 pressure by implementation of spectroscopic immersion probes into a modified autoclave reactor. The setup was successfully tested for the heterogeneously catalyzed hydrogenation of several imine substrates under H2 pressures up to 20 bar. The conversion of the imines could be analyzed by Raman spectroscopy and the product formation was observable by attenuated total reflectance FTIR spectroscopy (ATR‐FTIR), which illustrates the benefits of coupling complementary spectroscopic methods. Separate spectroscopic investigations show that imines intensively interact with the phosphoric acid ester that is used as catalyst modifier, indicated by a shift of the original ν(CN) band of the imine to higher wavenumbers. UV/Vis spectroscopic investigations reveal a distinct shift of the absorption edge to a higher wavelength. Furthermore, the formation of adsorbates on the surface of used Pt/Al2O3 catalysts, resulting mainly from adsorbed imine, was detected by FTIR spectroscopic analysis. The potential of UV/Vis spectroscopy in transmission mode for analyzing the organic components was tested. Due to its high sensitivity at low concentrations this method offers an additional possibility for a quantitative in situ analysis of the reaction progress in real time.
Netrin 1 provides a chemoattractive cue for the ventral migration of GnRH neurons in the chick forebrain
Authors: Murakami Shizuko , Ohki‐Hamazaki Hiroko , Watanabe Keisuke , Ikenaka Kazuhiro , Ono Katsuhiko
Published: January 2010

Hypothalamic gonadotropin‐releasing hormone (GnRH) neurons originate in the olfactory placode and migrate to the forebrain during embryonic development. We found that GnRH neurons migrated in two different modes in the chick medial telencephalon: they initially underwent axophilic migration in association with a subset of olfactory fibers in a dorsocaudal direction. This was followed by ventrally directed tangential migration to the basal forebrain. Since many of the ventrally migrating GnRH neurons did not follow distinct fiber fascicles, it is proposed that diffusible guidance molecules played a role in this migratory process. A long‐range diffusible factor, netrin 1, was expressed in the lower part of the commissural plate and the subpallial septum, but not along the axophilic migratory route of GnRH neurons. Failure of ventrally directed migration of GnRH neurons and their misrouting to the dorsomedial forebrain was induced by misexpression of netrin 1 in the dorsocaudal part of the septum near the top of the commissural plate, which is where the migration of GnRH neurons changed to a ventral direction. In such cases, a subset of olfactory fibers also extended, but close contact between aberrant fibers and misrouted GnRH neurons did not exist. A coculture experiment demonstrated that netrin 1 exerts an attractive effect on migrating GnRH neurons. These results provide evidence that netrin 1 acts as chemoattractant to migrating GnRH neurons at the dorsocaudal part of the septum and has the potential to regulate the ventral migration of GnRH neurons to the ventral septum and the preoptic area. J. Comp. Neurol. 518:2019–2034, 2010. © 2010 Wiley‐Liss, Inc.
Synthesis of strontium carbonate rods and hierarchical branches in the presence of two organic additives
Authors: Chen Long , Chen Guoping , Wang Xixi , Fang Hongxia , Wu Chengxiu , Xing Tiantian
Published: January 2010

In this paper, strontium carbonate (SrCO3) crystals have been synthesized in the presence of two organic additives, including sodium citrate and hexamethylenetetramine (HMT). Scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, X‐ray powder diffractometry and selected area electron diffraction (SAED) were used to characterize the products. The results indicate that SrCO3rods with the ratio of length to diameter about 20 are obtained in the aqueous solution containing sodium citrate. While polycrystalline SrCO3 hierarchical branches with about 10 μm length are produced by using HMT.The possible formation mechanism of the SrCO3crystals obtained in above two systems is discussed, which can be interpreted by particle‐aggregation based non‐classical crystallization laws. Sodium citrate and HMT may direct the formation of SrCO3 rod‐like or branch‐like structures by adsorbing onto certain facets of SrCO3 crystals. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and properties of PbGeO3 nanostructures
Authors: Wang Ning , Ding Jie , Li Guicun , Peng Hongrui
Published: January 2010

PbGeO3 nanostructures including nanofibers and nanobelts, have been synthesized via a facile hydrothermal method by the reaction between GeO2 and Pb(CH3COO)2·3H2O in the absence of any surfactant. The influences of synthetic parameters, such as reaction time, reaction temperature, and the concentration of ethylenediamine, on the morphologies and sizes of PbGeO3 nanostructures have been investigated. It is found that an evolution of PbGeO3 nanostructures from nanobelts to nanofibers is observed for the first time with the reaction time increased from 1 h to 6 h. The diameters of PbGeO3 nanofibers can be controled from 300–900 nm to 80–120 nm by adjusting the concentration of ethylenediamine. Under similar conditions, PbGeO3: Eu3+ nanofibers with rough surfaces can also be obtained. The photoluminescent spectra of PbGeO3: Eu3+ nanofibers exhibits two fluorescence emission peaks centered at around 591 and 614 nm as the excitation wavelength is 395 nm. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation and characterization of bioceramics produced from calcium phosphate cements
Authors: Andriotis O. , Katsamenis O. L. , Mouzakis D. E. , Bouropoulos N.
Published: January 2010

The present work reports a method for preparing calcium phosphate ceramics by calcination of calcium phosphate cements composed mainly of calcium deficient hydroxyapatite (CDHA). It was found that hardened cements calcinied at temperatures from to 600 to 1300 °C were transformed to tricalcium phosphates. Moreover the compressive strength was determined and porosity was estimated as a function of the calcination temperature. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tabular silver halide crystals prepared by controlled Ostwald growth in the presence of dimethyl sulphoxide
Authors: Dyonizy A. , Nowak P. , Mora C. , Król‐Gracz A. , Michalak E.
Published: January 2010

The results of research in the size and shape of silver bromide crystals precipitated by the Ostwald controlled growth method at the presence of dimethyl sulphoxide were presented in the paper. The silver bromide crystals were produced in the form of microcrystal suspension stabilised by gelatine. In the course of the synthesis of crystals, the constant concentration of dimethyl sulphoxide, concentration of excessive bromide ions and the constant ionic strength were achieved. The tabular crystals of silver bromide with their average size of 50 μm and their aspect ratio equal to 100 were obtained by means of this method. The suspensions of flat silver bromide crystals produced in this manner can be used in the production of high‐sensitivity materials. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defect structure and optical damage resistance of Hf:Fe:LiNbO3 crystals with various [Li]/[Nb] ratios
Authors: Sun Xiudong , Shi Hongxin , Luo Suhua , Jiang Yongyuan , Meng Qingxin
Published: January 2010

Hf:Fe:LiNbO3 crystals were grown in air by the Czochralski technique with various ratios of [Li]/[Nb]=0.94, 1.05, 1.20 in melt. The defect structure and location of doped ions were analyzed by the UV‐visible and infrared spectroscopy. The optical damage resistance ability of Hf:Fe:LiNbO3 crystals was measured by the photo‐induced birefringence change and the transmitted light spot distortion method. The results show that the optical damage resistance ability of Hf:Fe:LiNbO3 crystals is enhanced with the increase of the [Li]/[Nb] ratio. The dependence of the optical damage resistance of Hf:Fe:LiNbO3 crystals on the defect structure is discussed in detail. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A 14b 150 MS/s 140 mW 2.0 mm20.13µm CMOS A/D converter for software‐defined radio systems
Authors: Choi Hee‐Cheol , Yoo Pil‐Seon , Ahn Gil‐Cho , Lee Seung‐Hoon
Published: January 2010

This work proposes a 14 b 150 MS/s CMOS A/D converters (ADC) for software‐defined radio systems requiring simultaneously high‐resolution, low‐power, and small chip area at high speed. The proposed calibration‐free ADC employs a wide‐band low‐noise input sample‐and‐hold amplifier (SHA) along with a four‐stage pipelined architecture optimizing scaling‐down factors for the sampling capacitance and the input trans‐conductance of amplifiers in each stage to minimize thermal noise effect and power consumption. A signal‐insensitive 3‐D fully symmetric layout achieves a 14 b level resolution by reducing a capacitor mismatch of three MDACs. The prototype ADC in a 0.13µm 1P8M CMOS technology demonstrates a measured differential nonlinearity (DNL) and integral nonlinearity within 0.81LSB and 2.83LSB at 14 b, respectively. The ADC shows a maximum signal‐to‐noise‐and‐distortion ratio of 64 and 61 dB and a maximum spurious‐free dynamic range of 71 and 70 dB at 120 and 150 MS/s, respectively. The ADC with an active die area of 2.0mm2consumes 140 mW at 150 MS/s and 1.2 V. Copyright © 2010 John Wiley & Sons, Ltd.
On IIR‐based bit‐stream multipliers
Authors: Ng Chiu‐Wa , Wong Ngai , So Hayden Kwok‐Hay , Ng Tung‐Sang
Published: January 2010

We analyze the existing bi‐level IIR‐based bit‐stream multiplier and propose selection criteria for the key design parameter governing droop and phase linearity. Based on the proposed choice of parameter, we then extend the bi‐level design to tri‐ and quad‐level architectures that offer better signal‐to‐noise performance. Hardware complexity and noise performance of these designs are also contrasted with previously proposed FIR‐based bit‐stream multipliers. Useful design guidelines are subsequently drawn. Copyright © 2010 John Wiley & Sons, Ltd.
Fine‐needle aspiration diagnosis of a metastatic adult sclerosing rhabdomyosarcoma in a lymph node
Authors: Cantley Richard L. , Cimbaluk David , Reddy Vijaya , Iacusso Chiara , Gattuso Paolo
Published: January 2010

Adult sclerosing rhabdomyosarcoma (ASRMS) is a rare variant of rhabdomyosarcoma with a characteristic histological appearance of small, round cells in a dense, hyalinized stroma. Although nodal metastases of soft‐tissue sarcomas are considered uncommon, up to 5% overall are associated with lymph node metastases. Nonetheless, there is little literature on the cytologic characteristics of metastatic soft‐tissue sarcomas in lymph nodes, and to our knowledge, there are no reports of nodal metastasis of ASRMS diagnosed by fine‐needle aspiration (FNA) cytology. We report here a 55‐year‐old woman who presented with a right thigh mass and associated ipsilateral inguinal lymphadenopathy. Biopsy of the mass revealed a uniform population of small, round cells in a dense, sclerotic background. A diagnosis of ASRMS was rendered. Subsequently, the patient underwent FNA of an enlarged inguinal lymph node, which revealed an identical population of small, round cells in a dense, myxoid background. This case highlights the cytologic features of a rare form of rhabdomyosarcoma, and emphasizes the utility of FNA in the assessment of lymphadenopathy in the setting of a soft‐tissue sarcoma. Diagn. Cytopathol. 2010;38:761–764. © 2010 Wiley‐Liss, Inc.
Effects of excessive glucocorticoid receptor stimulation during early gestation on psychomotor and social behavior in the rat
Authors: Kleinhaus Karine , Steinfeld Sara , Balaban Jordan , Goodman Leora , Craft Tara S. , Malaspina Dolores , Myers Michael M. , Moore Holly
Published: January 2010

Severe psychological stress in the first trimester of pregnancy increases the risk of schizophrenia in the offspring. To begin to investigate the role of glucocorticoid receptors in this association, we determined the effects of the glucocorticoid dexamethasone (2 mg/kg), administered to pregnant rats on gestation days 6–8, on maternal behaviors and schizophrenia‐relevant behaviors in the offspring. Dams receiving dexamethasone exhibited increased milk ejection bouts during nursing. Offspring of dexamethasone‐treated dams (DEX) showed decreased juvenile social play and a blunted acoustic startle reflex in adolescence and adulthood, effects that were predicted by frequency of milk ejections in the dams. DEX offspring also showed increased prepulse inhibition of startle and reduced amphetamine‐induced motor activity, effects not correlated with maternal behavior. It is postulated that over‐stimulation of receptors targeted by glucocorticoids in the placenta or other maternal tissues during early gestation can lead to psychomotor and social behavioral deficits in the offspring. Moreover, some of these deficits may be mediated by alterations in postnatal maternal behavior and physiology produced by early gestational exposure to excess glucocorticoids. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52:121–132, 2010
Capillary electrophoresis of bone marrow stromal cells with uptake of heparin‐functionalized poly(lactide‐co‐glycolide) nanoparticles during differentiation towards neurons
Authors: Kuo Yung‐Chih , Shih Kun‐Hsiung , Yang Jen‐Tsung
Published: January 2010

This study analyzes the varying electrophoretic mobility and zeta potential of bone marrow stromal cells (BMSCs) during their differentiation towards neurons. Electrophoresis of primary BMSCs and neuron growth factor (NGF)‐induced neuron‐like cells with the uptake of heparin‐functionalized poly(lactide‐co‐glycolide) (PLGA) nanoparticles (NPs) are also investigated. Immunofluorescent images revealed that a high concentration of NGF accelerated the differentiation of BMSCs into neurons. When the concentration of NGF increased, the absolute values of electrophoretic mobility and zeta potential of the differentiating BMSCs increased. In addition, a longer inductive period yielded higher charge of the differentiating BMSCs and a smaller uptake amount of heparin‐functionalized PLGA NPs. However, an increase in the loading efficiency of heparin on PLGA NPs enhanced the uptake and reduced the electrical characteristics of the primary and differentiating BMSCs. Hence, a general rule is drawn that an increase in the uptake of heparin‐functionalized PLGA NPs decreased the electrophoretic mobility and zeta potential of BMSCs during differentiation towards neurons.
Total nucleotide analysis of Hydra DNA and RNA by MEKC with LIF detection and 32P‐postlabeling
Authors: Hassel Monika , Cornelius Michael G. , vom Brocke Jochen , Schmeiser Heinz H.
Published: January 2010

The model organism Hydra has been used for molecular studies for more than 20 years, however, its DNA base composition has not been determined yet. We have analyzed DNA and total RNA of the freshwater polyp Hydra magnipapillata with two independent procedures of high accuracy and sensitivity – fluorescence labeling of nucleotides followed by CE‐LIF detection and 32P‐postlabeling. DNA of Hydra was digested either to deoxyribonucleoside‐5′‐monophosphates or deoxyribonucleoside‐3′‐monophosphates selectively conjugated with the fluorescent dye 4,4‐difluoro‐5,7‐dimethyl‐4‐bora‐3a,4a‐diaza‐s‐indacene‐3‐propionyl ethylene diamine hydrochloride (BODIPY FL EDA) separated and detected using CE‐LIF. Both versions of the assay revealed a high A+T composition of 78 and 71%, whereas total DNA methylation (5‐methyldeoxycytidine) was 2.6 and 3.1%. Total Hydra RNA showed highest base levels for guanine (33%) and a level of 1.4% for pseudouracil. All values were in good agreement with those determined by the 32P‐postlabeling method.
Cyclic behavior of precast segmental concrete bridge columns with high performance or conventional steel reinforcing bars as energy dissipation bars
Authors: Ou Yu‐Chen , Tsai Mu‐Sen , Chang Kuo‐Chun , Lee George C.
Published: January 2010

The cyclic behavior of precast segmental concrete bridge columns with high performance (HP) steel reinforcing bars and that with conventional steel reinforcing bars as energy dissipation (ED) bars were investigated. The HP steel reinforcing bars are characterized by higher strength, greater ductility, and superior corrosion resistance compared with the conventional steel reinforcing bars. Three large‐scale columns were tested. One was designed with the HP ED bars and two with the conventional ED bars. The HP ED bars were fully bonded to the concrete. The conventional ED bars were fully bonded to the concrete for one column, whereas unbonded for a length to delay fracture of the bars and to increase energy dissipation for the other column. Test results showed that the column with the HP ED bars had greater drift capacity, higher lateral strength, and larger energy dissipation than that with fully bonded conventional ED bars. The column with unbonded conventional ED bars achieved the same drift capacity and similar energy dissipation capacity as that with the HP ED bars. All the three columns showed good self‐centering capability with residual drifts not greater than 0.4% drift. An analytical model referred to as joint bar‐slip rotation method for pushover analysis of segmental columns with ED bars is proposed. The model calculates joint rotation from the slip of the ED bars from two sides of the joint. Good agreement was found between analytical predictions and the envelope responses of the three columns. Copyright © 2010 John Wiley & Sons, Ltd.
High‐order methods for the numerical solution of the BiGlobal linear stability eigenvalue problem in complex geometries
Authors: González L. , Theofilis V. , Sherwin S. J.
Published: January 2010

A high‐order computational tool based on spectral and spectral/hp elements (J. Fluid. Mech. 2009; to appear) discretizations is employed for the analysis of BiGlobal fluid instability problems. Unlike other implementations of this type, which use a time‐stepping‐based formulation (J. Comput. Phys. 1994; 110(1):82–102; J. Fluid Mech. 1996; 322:215–241), a formulation is considered here in which the discretized matrix is constructed and stored prior to applying an iterative shift‐and‐invert Arnoldi algorithm for the solution of the generalized eigenvalue problem. In contrast to the time‐stepping‐based formulations, the matrix‐based approach permits searching anywhere in the eigenspace using shifting. Hybrid and fully unstructured meshes are used in conjunction with the spatial discretization. This permits analysis of flow instability on arbitrarily complex 2‐D geometries, homogeneous in the third spatial direction and allows both mesh (h)‐refinement as well as polynomial (p)‐refinement. A series of validation cases has been defined, using well‐known stability results in confined geometries. In addition new results are presented for ducts of curvilinear cross‐sections with rounded corners. Copyright © 2010 John Wiley & Sons, Ltd.
4D variational data assimilation for locally nested models: Complementary theoretical aspects and application to a 2D shallow water model
Authors: Simon Ehouarn , Debreu Laurent , Blayo Eric
Published: January 2010

We consider the application of a four‐dimensional variational data assimilation method to a numerical model, which employs local mesh refinement to improve its solution. We focus on structured meshes where a high‐resolution grid is embedded in a coarser resolution one, which covers the entire domain. The formulation of the nested variational data assimilation algorithm was derived in a preliminary work (Int. J. Numer. Meth. Fluids 2008; under review). We are interested here in complementary theoretical aspects. We present first a model for the multi‐grid background error covariance matrix. Then, we propose a variant of our algorithms based on the addition of control variables in the inter‐grid transfers in order to allow for a reduction of the errors linked to the interactions between the grids. These formulations are illustrated and discussed in the test case experiment of a 2D shallow water model. Copyright © 2010 John Wiley & Sons, Ltd.
A two‐phase adaptive finite element method for solid–fluid coupling in complex geometries
Authors: García Xavier , Pavlidis Dimitrios , Gorman Gerard J. , Gomes Jefferson L. M. A. , Piggott Matthew D. , Aristodemou Elsa , Mindel Julian , Latham John‐Paul , Pain Christopher C. , ApSimon Helen
Published: January 2010

In this paper we present a method to solve the Navier–Stokes equations in complex geometries, such as porous sands, using a finite‐element solver but without the complexity of meshing the porous space. The method is based on treating the solid boundaries as a second fluid and solving a set of equations similar to those used for multi‐fluid flow. When combined with anisotropic mesh adaptivity, it is possible to resolve complex geometries starting with an arbitrary coarse mesh. The approach is validated by comparing simulation results with available data in three test cases. In the first we simulate the flow past a cylinder. The second test case compares the pressure drop in flow through random packs of spheres with the Ergun equation. In the last case simulation results are compared with experimental data on the flow past a simplified vehicle model (Ahmed body) at high Reynolds number using large‐eddy simulation (LES). Results are in good agreement with all three reference models. Copyright © 2010 John Wiley & Sons, Ltd.