bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromium Compounds
Authors: Cotton F. Albert
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Iridium and Rhodium Complex Catalyzed Cycloadditions
Authors: Shibata Takanori
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Discovery of Novel Prostacyclin Mimetics with Highly Potent and Selective IP Receptor Agonists
Authors: Hattori Kouji
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Recent Progress on Nanovehicles
Authors: Shirai Yasuhiro , Morin Jean‐Francois , Sasaki Takashi , Guerrero Jason M. , Tour James M.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Molecular Designer Self‐Assembling Peptides
Authors: Zhao Xiaojun , Zhang Shuguang
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Artificial Nanomachines Based on Interlocked Molecular Species: Recent Advances
Authors: Balzani Vincenzo , Credi Alberto , Silvi Serena , Venturi Margherita
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Fluorine‐Based Crystal Engineering
Authors: Ono Taizo , Hayakawa Yoshio
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Rubidium and Cesium Carbonates
Authors: Kellogg Richard M.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
α‐Sodio Aldehydes, α‐Sodio Ketones, and Related Compounds
Authors: Juaristi E. , Melgar‐Fernandez R.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Antiaromaticity and Aromaticity in Carbocyclic Four‐Membered Rings
Authors: Eckert‐Maksic M. , Maksic Z. B.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
1,3‐Alternate, the Smart Conformation of Calix[4]arenes
Authors: Baklouti Lassaad , Harrowfield Jack , Pulpoka Buncha , Vicens Jacques
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Many‐Body Green′s Function Theory of Heisenberg Films
Authors: Froebrich P. , Kuntz P. J.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ion Pair Aggregates and Reactions; Experiment and Theory
Authors: Streitwieser Andrew
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Decision analysis to determine the appropriate treatment for low‐risk myelodysplastic syndromes
Authors: Sekeres Mikkael A. , Fu Alex Z. , Maciejewski Jaroslaw P. , Golshayan Ali‐Reza , Kalaycio Matt E. , Kattan Michael W.
Published: February 2007

BACKGROUND.

The myelodysplastic syndromes (MDS) are divided into low‐risk and high‐risk diseases. Predictive models for response to growth factors (GF) have been developed based on red blood cell transfusion needs and erythropoietin levels. For low‐risk MDS the optimal initial therapy (GF vs nongrowth factor [NGF] therapies, including differentiation and immunomodulatory agents) based on response rates to NGF and GF and survival, has not been defined.

METHODS.

A Markov decision analysis was performed on 799 low‐risk MDS patients treated with either GF or NGF to determine the appropriate initial therapy. The treatment strategies analyzed included initial GF or NGF therapies, assuming 3 different states: Patients were either in the good GF predictive group (low transfusion needs and low erythropoietin levels), intermediate, or the poor GF predictive group (high transfusion needs and high erythropoietin levels).

RESULTS.

In the good GF predictive group, initial therapy with GF improved survival compared with NGF therapies at 3.38 years vs 2.57 years for a typical MDS patient. The advantage of GF to NGF was lost when NGF therapies produced a response in ≥46% of patients. In the intermediate or poor GF predictive groups, NGF maximized survival, provided response rates for NGF were >14% and 4%, respectively, for each predictive group. Quality of life adjustment did not alter the preferred strategy.

CONCLUSIONS.

Modeling estimates suggest that patients who fall into a good GF predictive group should almost always receive GF initially, whereas those in intermediate and poor predictive groups should almost always be treated with NGF. Cancer 2007 © 2007 American Cancer Society.
Direct Electron Transfer Reaction of Ascorbate Oxidase Immobilized by a Self‐Assembled Monolayer and Polymer Membrane Combined System
Authors: Murata Kenichi , Nakamura Nobuhumi , Ohno Hiroyuki
Published: February 2007

This paper reports a novel enzyme‐immobilization method for the direct electron transfer (DET) reaction of ascorbate oxidase from Acremonium sp. HI‐25 (ASOM). ASOM was adsorbed onto a gold electrode modified with a self‐assembled monolayer (SAM) of alkanethiol derivatives and immobilized by a cationic polymer membrane and anionic ω‐carboxyalkanethiol combined system. The redox responses of the immobilized ASOM were investigated by cyclic voltammetry. We found that the DET reaction of ASOM was facilitated by this novel immobilization. On the other hand, the redox responses of poly(ethylene oxide) (PEO)‐modified ASOMs were also investigated. ASOM was modified with two types of PEO which possess straight chain‐shaped (PEO2000) or comb‐shaped conformation (PM67). As a result, the DET reactions of PEO‐modified ASOMs were also facilitated by this immobilization method. We concluded that this immobilization method is effective for promoting the DET reaction of ASOMs.
Determination of Thallium at A Silver‐Gold Alloy Electrode by Voltammetric Methods in Plant Material and Bottom Sediment Containing Cd and Pb
Authors: Krasnodębska‐Ostręga Beata , Pałdyna Joanna , Golimowski Jerzy
Published: February 2007

The applicability of the subtractive anodic stripping voltammetry (SASV) using the square‐wave mode at the silver‐gold alloy electrode has been studied for thallium determination in the presence of large amount of lead and cadmium in natural samples. 10 mmol L−1 perchloric acid was found as the most suitable supporting electrolyte for determination in synthetic solutions. The thallium peak was separated about 200 mV from Cd+Pb peak. Diethylenetriaminepentaacetic acid addition was necessary to determine thallium at the silver‐gold alloy electrode in digested plant and sediment. The determination limit was equal to 1.4 μg L−1. The method was validated by the inter‐method comparison (ICP‐MS).
Solid Oxide Fuel Cells: Fundamentals to Systems
Authors: Williams M. C.
Published: February 2007

The U.S. Department of Energy (DOE) Office of Fossil Energy's (FE) National Energy Technology Laboratory (NETL), in partnership with private industry, educational institutions and national laboratories, is leading the development and demonstration of high efficiency solid oxide fuel cells (SOFCs) and fuel cell‐turbine (FCT) hybrid power generation systems for distributed generation (DG) markets. The DOE FE DG program has three aspects: the Solid State Energy Conversion Alliance (SECA), Fuel Cell Coal Based Systems for central power, and the High Temperature Electrochemistry Center (HiTEC). NETL is partnering with Pacific Northwest National Laboratory (PNNL) in developing new directions in research under SECA for the development and commercialization of modular, low cost, and fuel flexible SOFC systems. The SECA initiative, through advanced materials, processing, and system integration research and development (R&D), will bring SOFC system cost to $400 per kilowatt (kW) by 2010 for stationary and auxiliary power unit (APU) markets. The SECA program is currently structured to include six competing industry teams supported by a crosscutting core technology program (CTP). DOE is ultimately concerned with coal‐based central power plants. Advanced aspects of solid oxide technology are part of HiTEC R&D.
Developments for Improved Direct Methanol Fuel Cell Stacks for Portable Power
Authors: Cremers C. , Scholz M. , Seliger W. , Racz A. , Knechtel W. , Rittmayr J. , Grafwallner F. , Peller H. , Stimming U.
Published: February 2007

Different aspects of the improvement of direct methanol fuel cell (DMFC) systems for portable power generation are investigated, in a project funded by the Bavarian state.

The materials research focuses on the development of improved catalysts, in particular for the oxygen reduction reaction. Some recent results on supported ruthenium selenium catalysts are reported.

In parallel, tests on other fuel cell materials are performed using MEAs made from industrial unsupported catalysts as the reference. These standard MEAs have catalyst loadings of about 11 mg cm–2 and, at high air flux, can deliver current densities of about 500 mA cm–2 and 100 mA cm–2 at 110 °C and 50 °C, respectively. At low air flux and 50 °C, current densities between 60 and 80 mA cm–2 are possible @ 500 mV.

Using these MEAs, different commercial gas diffusion materials are tested as the cathode backing. Thus, it is found that the Sigracet materials by SGL Carbon are the most suitable for operation at a low air flux.

Finally, a demonstration stack, comprised of up to ten cells, is developed using graphite PVDF compound bipolar plates by SGL Carbon. As will be reported, this stack shows a high homogeneity of cell voltages and stable operation under relevant conditions, using standard MEAs.
PEMFC Durability Test under Specific Dynamic Current Solicitation, Linked to a Vehicle Road Cycle
Authors: Harel F. , François X. , Candusso D. , Péra M.‐C. , Hissel D. , Kauffmann J.‐M.
Published: February 2007

The Laboratory of Electrical Engineering and Systems (L2ES) is concerned with fuel cell system durability and reliability. Since the lab is predominantly involved in the field of transport applications, one of the objectives is to study PEMFC ageing in different specific environments linked to electric vehicle operation.

The first phase of the durability program was devoted to the reference test of a 100 W three cell stack, operated in a stationary regime at roughly nominal conditions for 1,000 hours. The second phase, on which this paper is focused, is dedicated to the durability test of another 100 W stack placed under dynamical current constraints. The current cycle load applied is first computed from a standardized transportation mission profile (time vs. speed of vehicle) and then adapted to the power of the fuel cell tested. The gas supply strategy is defined and the work presented in this paper shows the importance of the gas flow management in providing highly dynamical current profiles. The experimental methodology is based on polarization curves as well as on electrochemical impedance spectroscopy measurements performed regularly throughout the ageing. The experimental results showing the degradation of the fuel cell performances are presented and analyzed.
Overland flow generation on hillslopes of complex topography: analytical solutions
Authors: Agnese Carmelo , Baiamonte Giorgio , Corrao Cecilia
Published: February 2007

The analytical solution of the overland flow equations developed by Agnese et al. (2001; Hydrological Processes 15: 3225–3238) for rectangular straight hillslopes was extended to convergent and divergent surfaces and to concave and convex profiles. Towards this aim, the conical convergent and divergent surfaces are approximated by a trapezoidal shape, and the overland flow is assumed to be always one‐dimensional. A simple ‘shape factor’ accounting for both planform geometry and profile shape was introduced: for each planform geometry, a brachistochrone profile was obtained by minimizing a functional containing a slope function of the profile. Minima shape factors are associated with brachistochrones; interestingly, brachistochrones associated with rectangular surfaces have a simple power‐law form. For a fixed profile shape, the rapidness of overland flow increases with the degree of divergence; for a fixed planform geometry, however, the overland flow associated with convex profiles is more rapid than that associated with concave profiles. An extended analytical solution is also proposed for the instantaneous response function. Copyright © 2007 John Wiley & Sons, Ltd.
The role of inhibitory control in false belief understanding
Authors: Flynn Emma
Published: February 2007

The aim of this study was to establish the nature of the relations between inhibitory control (IC) and false belief understanding (FBU). Twenty‐eight children, participating in an experimental condition, were tested on a battery of FBU and IC tasks every four weeks for six phases of testing. A control group of 14 children completed the battery only at the first and last phases of testing. Comparisons between the performance of the control and experimental groups showed that aggregate FBU scores and some IC tasks were susceptible to practice effects. Regression analysis at the group level found that early IC predicted later FBU, but that early FBU did not predict later IC. The individual children's profiles of performance supported this sequence of development, as the majority of children had good IC before developing good FBU. However, this sequence of development was not unique as a few children had good FBU skills before having good IC. Finally, trial‐by‐trial analyses showed that fluctuations in children's aggregate FBU scores could not be explained by similar fluctuations in IC, as would be expected by ‘expression’ accounts of the FBU/IC association. Further analyses considered task validity and the role of verbal ability. Copyright © 2007 John Wiley & Sons, Ltd.
Participatory processes and outcomes: the case of national irrigation system management in Bohol, Philippines
Authors: Maleza Maria Chona E. , Nishimura Yoshihiko
Published: February 2007

The adoption of participatory irrigation management in the Philippine national irrigation systems (NIS) began in the mid‐1980s, after positive results were observed in some participatory small‐scale communal irrigation systems. Yet, NIS performance remained generally poor. In the case of the Capayas Irrigation System – an NIS located in Bohol, Philippines – farmer participation is limited, thus sustainability is low. Limited participation is rooted in the absence of initiatives to mobilize the farmers prior to facility construction, inadequate government funds and the consequent priority bias against allocation for institutional development activities. This is also due to the absence of effective mechanisms both for ensuring sanctions against delinquent water users and for promoting incentives for participation. Mechanisms for coordination among various stakeholders are necessary in order to provide an enabling environment for irrigation. Important complementary actions include mainstreaming institutional development support, periodic monitoring and evaluation of the Irrigators' Associations (IAs), and improvements in physical structures of the secondary and tertiary facilities. Copyright © 2007 John Wiley & Sons, Ltd.
Antifibrotic effect of captopril and enalapril on paraquat‐induced lung fibrosis in rats
Authors: Ghazi‐Khansari Mahmoud , Mohammadi‐Karakani Ali , Sotoudeh Masoud , Mokhtary Parvin , Pour‐Esmaeil Ebraheim , Maghsoud Shirin
Published: February 2007

Although different treatment modalities have been implemented for pulmonary fibrosis, the results have not been promising and these conditions have been considered untreatable and irreversible. Thus, a plethora of new drugs has been tried for the control of this condition in recent years. This study examined the effects of two angiotensin‐converting enzyme inhibitors, captopril and enalapril, on paraquat‐induced pulmonary fibrosis in rats, through biochemical and histopathological parameters. Male albino Wistar rats were divided into eight groups (n = 4–5 each), including control, paraquat, captopril alone, captopril treatment and pre‐treatment, enalapril alone, enalapril treatment and pre‐treatment. After 21 days of treatment, the lungs were removed and the levels of hydroxyproline, glutathione and lipid peroxidation were determined. Angiotensin‐converting enzyme inhibitors showed no effect on glutathione and lipid peroxidation. The results also demonstrated that captopril and enalapril improved pulmonary fibrosis as shown by histopathology, as well as a decreased content of hydroxyproline (P < 0.001) in the lung tissue. In conclusion, the present findings suggest that the antifibrotic effect of these drugs may be related to the inhibition of angiotensin‐converting enzyme. Copyright © 2007 John Wiley & Sons, Ltd.
A novel ultra high molecular weight polyethylene–hyaluronan microcomposite for use in total joint replacements. II. Mechanical and tribological property evaluation
Authors: Zhang Min , Pare Philippe , King Richard , James Susan P.
Published: February 2007

The mechanical and tribological properties of a new biomaterial, an ultra high molecular weight polyethylene–hyaluronan (UHMWPE‐HA) microcomposite, were investigated in this article, which is Part II of a two‐part study. Part I presented the synthesis and physical/chemical characterization of the novel microcomposites. The microcomposite was developed for bearing surfaces of total joint replacements and was designed to enhance lubrication and improve wear resistance compared to noncrosslinked UHMWPE. Pin‐on‐flat wear tests with cross‐path motion demonstrated significant decreases for both the wear and wear rate of UHMWPE with the presence of hyaluronan (HA) within and on the microcomposite. Compared to noncrosslinked UHMWPE, a maximum decrease of 56% in wear and a maximum decrease of 31% in wear rate were observed at 1.0 million cycles. Inferior tensile properties were observed for the microcomposites when compared to noncrosslinked UHMWPE, which resulted from poor intermolecular entanglement of the UHMWPE caused by low remolding temperature throughout microcomposite manufacturing. Similar results were observed for the sham control, which was processed in the same way as the microcomposite, except for the addition of HA. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Tau binding to microtubules does not directly affect microtubule‐based vesicle motility
Authors: Morfini Gerardo , Pigino Gustavo , Mizuno Naoko , Kikkawa Masahide , Brady Scott T.
Published: February 2007

Tau protein is a major microtubule (MT)‐associated brain protein enriched in axons. Multiple functional roles are proposed for tau protein, including MT stabilization, generation of cell processes, and targeting of phosphotransferases to MTs. Recently, experiments involving exogenous tau expression in cultured cells suggested a role for tau as a regulator of kinesin‐1‐based motility. Tau was proposed to inhibit attachment of kinesin‐1 to MTs by competing for the kinesin‐1 binding site. In this work, we evaluated effects of tau on fast axonal transport (FAT) by using vesicle motility assays in isolated squid axoplasm. Effects of recombinant tau constructs on both kinesin‐1 and cytoplasmic dynein‐dependent FAT rates were evaluated by video microscopy. Exogenous tau binding to endogenous squid MTs was evidenced by a dramatic change in individual MT morphologies. However, perfusion of tau at concentrations ∼20‐fold higher than physiological levels showed no effect on FAT. In contrast, perfusion of a cytoplasmic dynein‐derived peptide that competes with kinesin‐1 and cytoplasmic dynein binding to MTs in vitro rapidly inhibited FAT in both directions. Taken together, our results indicate that binding of tau to MTs does not directly affect kinesin‐1‐ or cytoplasmic dynein‐based motilities. In contrast, our results provide further evidence indicating that the functional binding sites for kinesin‐1 and cytoplasmic dynein on MTs overlap. © 2006 Wiley‐Liss, Inc.
Sentinel lymph node biopsy is feasible even after total mastectomy
Authors: Intra Mattia , Veronesi Paolo , Gentilini Oreste D. , Trifirò Giuseppe , Berrettini Anastasio , Cecilio Rafaela , Colleoni Marco , Rietjens Mario , Luini Alberto , Paganelli Giovanni , Veronesi Umberto
Published: February 2007

Background

Previous mastectomy is unanimously considered to represent an absolute technical contraindication to sentinel lymph node biopsy (SLNB).

Methods

Four patients who underwent total mastectomy and plastic reconstruction with prosthesis, developed, during the follow up, a unique invasive limited local subdermic recurrence amenable to surgical excision, with clinically negative axillary nodes. In all patients preoperative lymphoscintigraphy with subdermal injection of 99mTc‐labeled colloidal particles correctly showed an axillary sentinel lymph node (SLN).

Results

Metastases in SLN were detected in two patients, and a complete axillary dissection followed. The remaining two patients had a negative SLN and no axillary clearance was performed.

Conclusions

In selected cases, the subdermal injection of radioisotope permits the identification of an axillary SLN, even in mastectomized patients. Despite SLNB in mastectomized patients being technically feasible, only a larger population and longer patient follow up could confirm its true predictive value. However, there are no anatomical or physiological reasons to exclude “a priori” this diagnostic opportunity. J. Surg. Oncol. 2007;95:175–179. © 2007 Wiley‐Liss, Inc.
Rapid determination of polyprenylated xanthones in gamboge resin of Garcinia hanburyi by HPLC
Authors: Song Jing‐Zheng , Yip Yue‐Keung , Han Quan‐Bin , Qiao Chun‐Feng , Xu Hong‐Xi
Published: February 2007

A rapid ion‐pair HPLC method was developed and validated for the determination of eight polyprenylated xanthones including three pairs of epimers, namely morellic acid (MA), 30‐hydroxygambogic acid (HGA), 30‐hydroxyepigambogic acid (HEGA), isogambogic acid (IGA), epiisogambogic acid (EIGA), gambogenic acid (GNA), gambogic acid (GA), and epigambogic acid (EGA), in gamboge resin of Garcinia hanburyi. The separation was performed on a narrow bore C8 column with isocratic elution using a mixture of methanol‐ACN‐40 mM KH2PO4 buffer (37.5 : 37.5 : 25 v/v/v, containing 0.1% tetradecyltrimethylammonium bromide). The newly developed method was used to determine the contents of the eight compounds present in the gamboge. Results showed that GA and EGA are the dominant components of gamboge. The content ratio of each epimer pair remained constant, indicating that the content ratio of epimers can be used as a specific characteristic for the quality control of gamboge.
Innovationsförderung in den Optischen Technologien – Eine Chance für die deutsche Wirtschaft
Authors: Schmitz Markus
Published: February 2007

Eine Grundvoraussetzung für die internationale Wettbewerbsfähigkeit des Wirtschaftsstandorts Deutschland ist die Entwicklung innovativer Produkte und Verfahren. Als Schrittmachertechnologien leisten die Optischen Technologien hierzu einen bedeutenden Beitrag. Das Bundesministerium für Bildung und Forschung fördert daher Forschungsvorhaben zur Erzeugung und Nutzbarmachung von Licht mittels Optischer Technologien. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
UV‐Laser in der Flachbildschirmherstellung
Authors: Herbst L. , Spiecker G.
Published: February 2007

Der Funktionsumfang mobiler elektronischer Geräte wächst ständig und damit der Bedarf an kleinen Hochleistungsflachbildschirmen auf Basis von Niedrigtemperatur‐Polysilizium‐Dünnschichttransistoren. Im gleichen Maße nimmt die Bedeutung der für die Herstellung von polykristallinem Silizium verwendeten UV‐Laser bei der Flachbildschirmherstellung zu. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Globo‐Welding – Ein innovatives Konzept für das 3D‐Laserfügen von Thermoplasten im Durchstrahlverfahren
Authors: Chen Jie‐Wei , Thielen Carsten
Published: February 2007

Bisherige Konzepte zum Laserstrahlschweißen sind durch das Zusammenspiel von Spannvorrichtung und Strahlführung zumeist auf handhabbare 2D‐Anwendungen begrenzt. Das innovative Konzept des Globo‐Welding erweitert dieses Spektrum auf dreidimensionale und großflächige Anwendungen. Möglich wird dieses durch den Verzicht der konstruktiv aufwändigen Spannvorrichtung.
Die Strahlqualität von Lasern – Wie bestimmt man Beugungsmaßzahl und Strahldurchmesser in der Praxis?
Authors: Eichler Jürgen , Dünkel Lothar , Eppich Bernd
Published: February 2007

Die Fokussierbarkeit von Lasern nach der ISO‐Norm 11146 wird durch die Beugungsmaßzahl M2 beschrieben. Diese gibt den Divergenzwinkel eines Laserstrahls im Verhältnis zur Divergenz eines idealen Gauß‐Strahls mit gleichem Durchmesser an der Strahltaille an. Zur Bestimmung von M2 müssen die Strahldurchmesser längs einer Strahltaille vermessen werden. Durch Kurvenanpassung an den Strahlverlauf werden der Durchmesser der Strahltaille, die Strahldivergenz und M2 ermittelt.
Novel π‐Electron Extension System via Chromophores Self‐Polymerization to Enhance the NLO Efficiency
Authors: Tsai Hsieh‐Chih , Yu I‐Chen , Chang Po‐Hsun , Yu Da‐Cyuan , Hsiue Ging‐Ho
Published: February 2007

A new strategy for the self‐polymerization of chromophores is investigated to develop a 2,7‐carbazole‐based nonlinear optical (NLO) conjugated polymer with an increasing conjugation length of chromophores. Elongation of the conjugation‐path length in chromophores has established engineering guidelines to enhance optical nonlinearity. Compared with the traditional synthesis of an NLO polymer, the chromophores should be well‐designed at a limited conjugation spacer, and then incorporated into a polymer matrix. In this research, the π‐conjugation spacer of chromophores extended perpendicularly to the dipole of chromophores during the polymerization process. Furthermore, this study marks the first research of integrating the π‐electrons of chromophores and conjugated polymers. These conjugated backbones promote a bulk‐polarization response, leading to large NLO coefficients.

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A Novel Approach to Magnetic Nanoadsorbents with High Binding Capacity for Bovine Serum Albumin
Authors: Sun Yabin , Ding Xiaobin , Zheng Zhaohui , Cheng Xu , Hu Xinhua , Peng Yuxing
Published: February 2007

Magnetic nanoadsorbents using Fe3O4 nanoparticles as cores and poly(methyl acrylic acid) (PMAA) as ionic exchange groups were prepared through our novel approach. Two steps were involved in this approach: the first was to functionalize the magnetic nanoparticles (MNPs) with methacrylate double bonds via the combination of ligand exchange and condensation of methacryloxypropyltrimethoxysilane(MPS); the second was to graft PMAA chains onto the surface of MNPs through radical polymerization. The success of the various surface functionalization steps was ascertained using FTIR and XPS. The as‐synthesized PMAA‐coated MNPs were effective in binding bovine serum albumin (BSA) with a high capacity of 1 300 mg · g−1.

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Conflict resolution: benchmarking water utility performance
Authors: Berg Sanford V.
Published: February 2007

The water sector has economic and symbolic importance for citizens in developing countries. Water utility benchmarking is no panacea for improving water sector performance. Nevertheless, it can contribute to addressing four sources of conflict in the design and implementation of policies: cognitive conflicts (based on technical disagreements regarding how data might be analysed and interpreted), interest conflicts (where suppliers and demanders obtain different benefits and costs under alternative policies), values conflicts (involving ideology or personal preferences regarding water sector outcomes) and authority conflicts (stemming from jurisdictional disagreements over who has the last word). These potential sources of conflict characterise most politically‐charged situations, including water supply management. This article examines the extent to which water utility benchmarking facilitates conflict resolution. Without information on historical trends, current baselines and realistic targets, conflicts over reforms to improve sector performance can weaken systems that are already fragile, particularly those in developing countries. This article attempts to improve our understanding of the links between sources of conflict, government approaches for dealing with conflict and the role of water utility benchmarking as a complementary strategy for addressing policy issues. Benchmarking is one way regulators and managers can promote conflict resolution that allows participants to focus on performance. The principles apply to all sectors with significant state oversight. Copyright © 2007 John Wiley & Sons, Ltd.
The changing face of ‘Drivers of Change’
Authors: Scott Zoe
Published: February 2007

In 2001 the UK Government's Department for International Development (DFID) launched a new way of conducting political economy analysis, called ‘Drivers of Change’ (DoC). DoC is now well known amongst international development practitioners and professionals. This article provides an introduction to DoC, explaining what it is, where DoC analysis has taken place and which organisations have been involved. It also explores the history and background to DoC, outlines its effect on other bi and multi‐lateral donors and shows how the approach has evolved over the last 5 years. The final section of the article analyses some of the current limitations in the way DoC analysis is used by DFID and predicts how the approach may develop in the future. Copyright © 2007 John Wiley & Sons, Ltd.
Preparation and characterization of hyaluronan/chitosan scaffold cross‐ linked by 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide
Authors: Deng Yu , Liu Dengru , Du Guocheng , Li Xiufen , Chen Jian
Published: February 2007

A novel biocompatible scaffold was prepared by cross‐linking hyaluronan (HA) and chitosan (CS). The carboxyl groups of HA were activated by 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide (EDC) and then cross‐linked with amino groups of CS by forming amide bonds. The HA/CS scaffold thus prepared was characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and differential scanning calorimetry. FTIR spectra showed that the absorbance of the amide (1550 cm−1) and carbonyl (1633 cm−1) bond in the cross‐linked scaffold was stronger than that in HA or CS. SEM micrographs showed that the cross‐linked scaffold produced at low EDC concentration had an intertwisted ribbon‐like microstructure, while the product prepared at higher EDC concentration had a porous structure. The concentration of EDC in the reaction system greatly affected the structure and properties of the HA/CS scaffold. The prepared scaffold could strongly resist degradation by hyaluronidase, free radicals in vitro and stress. Copyright © 2007 Society of Chemical Industry
Vitamin E succinate inhibits NF‐κB and prevents the development of a metastatic phenotype in prostate cancer cells: Implications for chemoprevention
Authors: Crispen Paul L. , Uzzo Robert G. , Golovine Konstantin , Makhov Peter , Pollack Alan , Horwitz Eric M. , Greenberg Richard E. , Kolenko Vladimir M.
Published: February 2007

BACKGROUND

NF‐κB and AP‐1 transcriptional factors contribute to the development and progression of prostate malignancy by regulating the expression of genes involved in proliferation, apoptosis, angiogenesis, and metastasis.

METHODS

NF‐κB and AP‐1 activities were examined by TransAm assay. Cytokines levels were assessed by ELISA. ICAM‐1 and gp130 expression was examined by flow cytometry. Cell adhesion was examined by the ability of cells to adhere to fibronectin‐coated plates. Cell viability was determined by propidium iodide staining.

RESULTS

Treatment with α‐tocopherol succinate (VES) inhibits NF‐κB but augments AP‐1 activity, reduces expression of IL‐6, IL‐8, and VEGF, suppresses cell adhesion, ICAM‐1 and gp130 expression in androgen‐independent PC‐3, DU‐145, and CA‐HPV‐10 cells. VES supplementation also decreases the expression of anti‐apoptotic XIAP and Bcl‐XL proteins and sensitizes androgen‐dependent LNCaP cells to androgen deprivation.

CONCLUSIONS

Our findings propose a potential mechanism of VES‐mediated anti‐tumor activity and support the role of vitamin E analogs as potential chemopreventative agents against prostate cancer. Prostate 67: 582–590, 2007. © 2007 Wiley‐Liss, Inc.
The Design and Evaluation of Placebo Material for Crude Herbals: Artemisia afra Herb as a Model
Authors: Dube A. , Manthata L. N. , Syce J. A.
Published: February 2007

Herbal materials are known to present significant challenges with regard to designing credible placebos. This study intended to demonstrate the possibility of designing placebo material for crude herbals and used Artemisia afra, a popular traditional herbal medicine in South Africa, as a model. To produce the placebo, step‐wise solvent extractions were conducted on the plant leaves and the process was monitored spectrophotometrically and using high performance liquid chromatography (HPLC) with diode array detection. The odour and taste between the placebo and A. afra was matched by inclusion of linalool and sodium saccharin, respectively. The muscle relaxant activity of the placebo was evaluated using an isolated guinea‐pig tracheal muscle preparation. The UV absorbance of the extracts and the HPLC chromatograms, showed that most of the phytochemical constituents had been removed and the placebo closely resembled the A. afra leaves. The EC50 of the placebo and the leaves were 4846.00 and 68.49 mg/mL, respectively, which showed that not only did the A. afra leaves possess muscle relaxant activity, but that the placebo did not possess any significant activity compared with the A. afra leaves (p value 0.0001). These results demonstrated that it is possible to design credible, pharmacologically inert placebo material for crude herbals. Copyright © 2007 John Wiley & Sons, Ltd.
The structure of the intertropical front over N.W. India during the S.W. Monsoon
Authors: Sawyer J. S.
Published: February 2007

This paper investigates the structure of the intertropical front over N.W. India by means of the daily radio‐sonde and meteorological flight observations made during ten days of undisturbed weather during the monsoon of 1945. The conclusions are incorporated in the schematic cross sections (Figs. 12 and 13).

In the course of the investigation it is found that the winds in the continental air are notably sub‐geostrophic. No explanation of this is given.
The estimation of vertical motion in the atmosphere
Authors: Graham R. C.
Published: February 2007

A procedure is suggested by which an estimate of the ascent or descent of air can be obtained by use of constant‐level maps and upper air soundings plotted on tephigrams or charts of a similar type. Results obtained by this method are compared with those by other methods. Examples of its use in forecasting are given.
Evaporation from extensive surfaces of water roughened by waves
Authors: Norris Ramalingam
Published: February 2007

The problem of evaporation from large expanses of water is of fundamental importance. The evaporation from oceans is of importance in studying the amount of water vapour which an air mass receives while flowing over the ocean. Among recent investigations on the problem of evaporation may be mentioned in particular those of Sverdrup (1936), Millar (1937), and Montgomery (1940). But the final conclusive results of these authors differ very much from each other. For instance, Sverdrup (1937–8) concludes that the evaporation from a hydrodynamically rough surface must be twice as great as that from a smooth surface, while Montgomery infers it to be about the same in both cases. The question is reconsidered below, the work of these authors being followed to a certain extent, but not entirely. The differences are emphasised wherever necessary. The present investigation leads to the result that the evaporation from a hydrodynamically rough surface must be about four times as great as that to be expected from a smooth surface of water.
The effect of freezing and melting processes on the daily temperature curve at quebec city
Authors: Longley Richmond W.
Published: February 2007

A study was made of the frequency distribution of the daily maximum and minimum temperatures for the city of Quebec for the periods 1 February to 31 May and 1 September to 31 December. It was discovered that during the period when the snow was melting there was a damping effect of approximately 2°F on the maximum temperature on those days when the temperature rose above freezing. After the snow disappeared and the ground thawed out, there was a corresponding damping of about 1°F on the minimum temperature on those days when it approached freezing. The damping effect in the autumn is less than 1°F. Other features of these frequency distributions are also brought out.
Physical interactions between tropical and temperate latitudes
Authors: Priestley C. H. B.
Published: February 2007

The poleward transports of momentum and angular momentum, enthalpy, water vapour, and total energy are studied at a number of upper‐air stations in the high‐pressure belt. The results confirm earlier suggestions of a mean meridional circulation across this belt; this circulation is found to contribute about one half the total poleward transport of both energy and angular momentum, and also to make a substantial contribution to the maintenance of the total kinetic energy of the atmosphere. The meridional circulation appears notably stronger in winter than in summer. The poleward transport of angular momentum to the Westerlies reflects this variation, whereas there is relatively little seasonal variation in the contribution from eddy flux (horizontal rotations) or in the total generation of angular momentum in the Easterlies of low latitudes.

Variations of eddy flux with height are examined and certain general features (Priestley, Q.J., 1949) confirmed. The lowest 500 mb of atmosphere make no appreciable contribution to the net eddy flow of momentum, the transport occurring mainly at the 300 mb and 200 mb levels.

The results also provide a measure of the difference between total annual precipitation and evaporation in the tropical zone.
Observations with a directional raingauge
Authors: Lacy R. E.
Published: February 2007

An octagonal raingauge, which was set up to study the way in which rain impinged on vertical surfaces, is described. Observations made over a period of 12 years are analysed, showing that, in the London area, walls with moderate exposure to wind and facing approximately SW. receive most rain, equivalent to about 1/4 of the normal rainfall, and walls facing N. receive least, about 1/16 the normal rainfall. An equation connecting the mean incident angle of the rain on the ground with the wind speed is derived, and an attempt is made to obtain an indication of raindrop diameter.
Drop‐size distribution in cloud and fog
Authors: Best A. C.
Published: February 2007

Experimental data relating to drop‐size distribution in cloud and fog are examined and it is shown that in many cases the size distribution can be represented by the formula

where F is the fraction of liquid water in the air comprised by drops with diameter less than x. The constant a increases with the liquid water content of the cloud. It is not clear what governs the value of the constant n but a reasonable mean value is about 3.3.

It is shown that, if the drop‐size distribution can be described by the equation quoted above the median volume diameter is the most suitable parameter for describing the average size of the cloud particles when the value of n is not known.
The relation between thickness of cloud layers and their transmission of light
Authors: Atkins W. R. G.
Published: February 2007

Apparent minimal cloud‐transmission percentages for Bircham Newton are plotted against vertical distribution of clouds observed by aircraft, and cloud amount. With under 20 per cent transmission great cloud thickness is possible, but with over 30 per cent no great thickness of low cloud occurs. Percentage frequencies of minimal cloud transmission are given for a year.
On the propagation and growth of jet‐stream waves
Authors: Petterssen Sverre
Published: February 2007

On the assumption of adiabatic and frictionless motion general expressions for the rates of propagation and growth of wave‐shaped circulation patterns are derived, allowing the wind field to possess such general characteristics as vertical velocity, lateral shear, divergence, etc. The general equations are specialized to apply to sinusoidal wave models resembling the type of waves that occur in connection with strong concentrated currents (e.g., the jet stream) in the middle and upper troposphere in middle latitudes. It is shown that the rate of propagation of these waves is determined primarily by the wind speed, the wave length, the ‘width’ of the current, and the meridional variation of the Coriolis parameter while the Coriolis parameter itself is relatively unimportant. It is shown that the growth rate is determined primarily by the meridional variation of the Coriolis parameter and the orientation of the troughs and wedges relative to the meridians. Some comments are offered on the propagation of jet‐stream waves associated with ocean currents.
Theory of the radar upper band
Authors: Wexler R.
Published: February 2007

It is shown how the growth of a layer of graupel and the subsequent depletion of the cloud liquid‐water content below a critical value is capable of explaining the observations pertaining to the radar upper band, described by Bowen.
A cloud‐droplet sampler for use on aircraft
Authors: Squires P. , Gillespie C. A.
Published: February 2007

An instrument is described with which cloud‐droplet samples can be taken from an aircraft by exposing momentarily glass rods coated with magnesium oxide. Exposures can be repeated about every three seconds. (i.e., about every 200 m). The spectra found in a traverse through a cumulus are shown.

Features of the distribution of spectra can be determined which could not readily be found by methods which average over some distance, or by sampling methods not capable of being repeated so often. The samples are too widely spaced, however, to yield a coherent sequence of spectra across a cumulus.
Schemes for the study of hemispheric exchange processes
Authors: Starr V. P. , White R. M.
Published: February 2007

Two alternative existing schemes for the classification of eddy‐exchange processes are examined. It appears that each scheme is adapted to the study of distinct physical questions concerning the atmosphere. Hemispheric wind data are used to illustrate the inherent differences of the two methods.

A relatively high positive spatial correlation is found between the eastward and northward components of the mean vector wind along the latitude circle in the vicinity of 30°N. at the level of the jet stream.
Measurements of condensation nuclei over the North Atlantic
Authors: Moore D. J.
Published: February 2007

Measurements of the total concentration of condensation nuclei and of the concentration and size distribution of large sea‐salt nuclei have been made on board an Ocean Weather Ship in the North Atlantic over a period of three weeks. Total nucleus counts varied between 77/cm3 and 2,460/cm3, the numbers decreasing with increase in the intensity of vertical mixing as indicated by cloud type.

The concentration of large nuclei (mass > 10−11 g) was found to increase markedly with wind speed and wave height, but no corresponding increase was found for the total nucleus population.

An analysis of the visibility observations at the Ocean Weather Ship Stations ‘Item’ and ‘Jig’ shows that the opacity for a given humidity increases with wind speed and wave height and that this increase can be accounted for by the observed increase in the concentration of large nuclei.

Consequently if the rate of production of small nuclei at the sea surface increases with wind speed, such increase (for wind speeds up to 18 m/sec) does not materially affect the total nucleus population a few metres above the surface.
Natural removal of atmospheric pollution during fog
Authors: Meetham A. R.
Published: February 2007

The average lives of smoke particles and sulphur‐dioxide molecules in the air are compared in average and foggy conditions. Possible mechanisms of removal during fog are considered.
Note on the structure of the high altitude strong‐wind belt in the Middle East in winter
Authors: Bannon J. K.
Published: February 2007

By referring the upper‐air observations at Habbaniya and Bahrein for January 1951 to the estimated central axis of the strong stream a meridional cross‐section is constructed showing the mean structure for that month of the strong‐wind belt in the upper troposphere over Iraq. This mean structure should apply to the stream on a particular day in contrast to the mean flow as usually computed which shows the average conditions above each observing station. The stream is found to be broad and without strong horizontal gradients. Its axis is at about 190 mb, its mean position about 32°N and the breadth of the region of highest speeds (100 kt or more) about 800 mi.
A sensitive recording dew‐balance
Authors: Jennings E. G. , Monteith J. L.
Published: February 2007

The instrument described gives a continuous record on photographic paper of the change in weight of a naturally exposed grass surface, 330 cm2 in area. The sensitivity is 2 mg cm−1 per cm of record and the time scale is 0.5 hr/cm. Observations suggest that on very calm nights the condensation of vapour reaching the surface by diffusion from the atmosphere is only a small fraction of the total ‘dew.’ The maximum rate of deposition that has been observed on short grass is 0.03 mm hr−1.