bluuebunny/crossref_metadata_2025 huggingface dataset:
Responsibility for safety and risk minimization: Outline of an attribution‐based approach regarding modern technological and societal systems
Authors: Lenk Hans
Published: June 2003

After the terrorist attacks of September 11, 2001, questions of safety management and responsibility became topical to a high degree. The notion of individual responsibility is, also for institutional and corporate decisions and enterprises, of particular importance for technology. Problems of collective and corporate responsibility are becoming and still will become even more topical. Engineering ethics codes should be developed, improved, and operationally implemented. Rules of priority outlined here for handling responsibility conflicts must be elaborated much further. This seems necessary to meet the ideal requirements of social responsibility for technology in society. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 203–222, 2003.
Does safety science fulfill the requirements of modern technical systems?
Authors: Kuhlmann Albert
Published: June 2003

Since the idea of safety science was first conceived, technical systems have grown larger and increasingly complex, thus causing a pronounced impact on the complexity of required safety analyses and risk calculations. The author emphasizes his point of view that the physical risk definition provides the most appropriate concept for engineers when it comes to planning including risk cadastres. In order to avoid human errors, he pleads for the consideration of human factors in the early design phase and for interdisciplinary cooperation. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 223–230, 2003.
The acceptance of systemic thinking in various fields of technology and consequences on the respective safety philosophies
Authors: Geysen Willy , Verbruggen Johan
Published: June 2003

Systemic thinking aims to develop a common language that makes it possible for scientists of different disciplines and technologies to communicate with one another. The specific methodology of systemic thinking is a means of tackling complex, interrelated problems by applying a holistic approach that focuses on the interrelation of individual aspects. In this article, an attempt is made to show the impact of systemic thinking in different areas of science and technology. In particular, the authors argue that a multidisciplinary, systemic approach can play an important role in developing a general theory of safety science. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 231–242, 2003.
Technical responsibility management— an indispensable element of corporate governance
Authors: Althoff Jürgen
Published: June 2003

We define technical responsibility management as the organized fulfillment of all the legal and other responsibilities connected with the use of technical means of production and installations in an enterprise. To act legally responsible even under the condition of permanently changing regulations and to produce cost efficiency at the same time, a responsibility management system (RMS) is being presented, a system that, as it were, automatizes and rationalizes the fulfillment of all liabilities valid at the time. All existing installations in the enterprise, as well as all relevant legal provisions, are represented in adequate form by experts and, resulting from this, software determines optimized schedules that also take into account additional secondary operational conditions. Internet/intranet technology even permits complete outsourcing. RMSs heighten the safety level in the enterprise, provide legal security, and open up hitherto inaccessible savings potentials. The author pleads for the OECD principles for good “Corporate Governance Systems (Management and Controlling)” to demand the future introduction of RMSs. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 253–259, 2003.
Safety management in production
Authors: Hale A.R.
Published: June 2003

The last 20 years have seen the development of broad agreement on the necessary functions to be fulfilled by a safety management system and how they relate to each other in a coherent whole. The article describes these functions and reviews subjects that still need study, notably organizational culture, conflict, management in nonbureaucratic organizations, safety auditing, and safety in the learning organization. It is organized under four headings: what we know, what we believe but have no proof of, what we may be mistaken about, and what we face as challenges and unresolved issues for the coming years. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 185–201, 2003.
Synthesis and evaluation of 5,7‐dichloro‐4‐(3‐{4‐[4‐(2‐[18F]fluoroethyl)‐piperazin‐1‐yl]‐phenyl}‐ureido)‐1,2,3,4‐tetrahydroquinoline‐2‐carboxylic acid as a potential NMDA ligand to study glutamatergic neurotransmission in vivo
Authors: Piel Markus , Schirrmacher Ralf , Höhnemann Sabine , Hamkens Wilhelm , Kohl Beate , Jansen Michaela , Schmitt Ullrich , Lüddens Hartmut , Dannhardt Gerd , Rösch Frank
Published: June 2003

The neurotransmitter glutamate is thought to be crucially involved in a huge number of neurological and psychiatric disorders, such as Morbus Parkinson, Alzheimer's disease and schizophrenia. Aiming at an improved diagnostic tool for PET a new [18F]fluorine labelled NMDA receptor ligand was developed that may potentially allow the in vivo visualization of glutama‐tergic neurotransmission. The 19F‐analogue trans‐5,7‐dichloro‐4‐(3‐{4‐[4‐(2‐fluoroethyl)‐piperazin‐1‐yl]‐phenyl}‐ureido)‐1,2,3,4‐tetrahydro quinoline‐2‐carboxylic acid was synthesised to determine the binding affinity, lipophilicity and biodistribution of the ligand. This substance exhibits a Ki of 12 nM for the glycine binding site using [3H]MDL‐105,519 assays on pig cortical membranes. A logD of 1.3 was determined for this compound according to the OECD guidelines employing the HPLC method. Radiosynthesis of this ligand was achieved by labelling the precursor trans‐5,7‐dichloro‐4‐[3‐(4‐piperazin‐1‐yl‐phenyl)‐ureido]‐1,2,3,4‐tetrahydroquinoline‐2‐carboxylic acid methyl ester with 2‐[18F]fluoroethyltosylate and subsequent cleaving of the methyl ester moiety, resulting in an overall decay corrected yield of 35% of the final product trans‐5,7‐dichloro‐4‐(3‐{4‐[4‐(2‐[18F]fluoroethyl)‐piperazin‐1‐yl]‐phenyl}‐ureido)‐1,2,3,4‐tetrahydroquinoline‐2‐carboxylic acid. The biodistribution kinetics of this compound were determined with Sprague Dawley rats ex vivo for brain, liver, kidney, and bone. The ligand showed a maximum brain uptake 30 min.p.i. of about 0.1% ID/g. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis of [14C] Sarin
Authors: Norlin Rikard , Lindberg Gösta
Published: June 2003

Synthetic routes for the synthesis of [14C] sarin and related nerve agents are described. Triethyl phosphite and [14C] methyl iodide are reacted in the Michaelis–Arbusov reaction to produce diethyl methyl phosphonate which is converted to methylphosphonic acid by hydrolysis. After chlorination and subsequent fluorination the final product is formed by reaction with the appropriate alcohol. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis of JTT‐501 and its metabolite JTP‐20604 labelled with 13C
Authors: Pignatti A. , Giribone D. , Felicini C. , Fontana E.
Published: June 2003

JTT‐501 specifically labelled with 13C was obtained via a four‐step synthesis at an isotopic enrichment level of 99% and in 14% overall chemical yield starting from 4‐hydroxy‐[ring‐U‐13C6]benzaldehyde (3). The hydrogenation of [13C6]JTT‐501 over Pd/C gave [13C6]JTP‐20604 in 90% chemical yield. Copyright © 2003 John Wiley & Sons, Ltd.
A convenient synthesis of 13C4‐Leflunomide and its primary metabolite 13C4‐A77 1726
Authors: Faragher Robert J. , Motto John. M. , Kaminski Maciej A. , Schwan Adrian L.
Published: June 2003

A convenient synthesis of leflunomide and its primary pharmacologically active metabolite A77 1726, each labeled with four 13C atoms has been achieved. Starting from 13C4‐ethyl acetoacetate, each step of the synthesis proceeds in 60–82% yield. Analysis of the mass spectra of the labeled and unlabeled materials demonstrates that the compounds prepared herein will be suitable as analytical standards for bioavailability studies. Copyright © 2003 John Wiley & Sons, Ltd.
Feasibility of palladium‐catalyzed isotopic exchange between sodium [125I]I and 2‐iodo‐para‐carborane
Authors: Eriksson Ludvig , Tolmachev Vladimir , Sjöberg Stefan
Published: June 2003

Many ortho‐/meta‐/para‐closo‐carborane derivatives have been proposed for boron neutron capture therapy. However, it is difficult to follow their pharmacokinetics in patients, which creates a risk of suboptimal treatment. Adding a radioactive label to closo‐carboranes may simplify pharmacokinetic studies. This paper reports on a study of the feasibility of palladium‐catalyzed isotopic exchange of iodinated closo‐carborane with radioisotopes of iodine. 2‐iodo‐para‐carborane was selected as a model compound. It was shown that such isotopic exchange is possible and provides a high yield (83±4.2%) after 40 min of reaction time. The reaction conditions were optimized, and it was demonstrated that the presence of tetra n‐butylammonium hydrogensulfate is important in order to stabilize the catalyst and to give reproducibility of the labeling. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis of 99mTc(CO)3‐mebrofenin via [99mTc(OH2)3(CO)3]+ precursor and comparative pharmacokinetics studies with 99mTc‐mebrofenin
Authors: Kothari Kanchan , Joshi Sangeeta , Venkatesh Meera , Ramamoorthy N. , Pillai M.R.A.
Published: June 2003

The organometallic precursor fac‐[99mTc(OH2)3(CO)3]+ was reacted with trimethyl‐bromoacetanilido‐iminodiacetic acid (mebrofenin) in phosphate buffered saline (pH 7) at 70°C for 1 h to produce the complex, 99mTc(CO)3‐mebrofenin, in >95% yields. High performance liquid chromatography analysis indicated the formation of a single species. In vitro studies of 99mTc(CO)3‐mebrofenin showed that the complex is stable for 24 h. No decomposition or alteration of the complex was observed in the presence of excess amount of cysteine and histidine. 99mTc‐mebrofenin was also prepared for comparative evaluation by the conventional method using a ready to use kit HPLC analysis of this complex showed presence of two species. Biodistribution studies in normal Swiss mice with 99mTc(CO)3‐mebrofenin showed hepatobiliary clearance. However, the retention in liver was higher (13% at 1 h p.i.) as compared to that of 99mTc‐mebrofenin (3.4% at 1 h p.i.). Copyright © 2003 John Wiley & Sons, Ltd.
Abstracts of the 12th IIS (UK Group) Symposium
Authors: Staunton J , Gates Paul , Kearney Gordon , Fonseca Tatiana , Anderson J.C. , Broughton S. , Glaser M. , Booker‐Milburn Kevin I. , Caroll M. A. , Rzepa H. S. , Pike V. W. , Widdowson D. A. , Ellames George J. , Gibson Jennifer S. , Herbert John M. , Smith David I. , Wilkinson D J , Mather A N , Hickey M J , Kingston L P , Lockley W J S , Hollis Stephen , Johnston Grant , Bloom A. Jon , Johnström Peter , Davenport Anthony P.
Published: June 2003

“Synthesis & Application of Labelled Compounds 2002”

Isotopes and Mass Spectrometry

Carbon‐13 Labelling to Aid the Development of the Catalytic Alkenation of Carbonyls

Production and Applications of 124I for Positron Emission Tomography

Organic Photochemistry: Synthetic Approaches to Alkaloids in a Reagentless Environment

Fluorinaion for Positron Emission Tomography

Synthetic Consequences of Kinetic Isotopes Effects: Synthesis of [13 C6]‐SR31742A For Human Trail Purposes

Tritio‐Dehalogenation: New Variants on an Old Theme

The Synthesis of BOC‐L‐Proline‐[14C2] Benzyl Ester

Peptide Labelling with Fluorine‐18
Automated commercial synthesis system for preparation of O‐(2‐[18F]fluoroethyl)‐L‐tyrosine by direct nucleophilic displacement on a resin column
Authors: Tang Ganghua , Tang Xiaolan , Wang Mingfang , Luo Lei , Gan Manquan , Huang Zuhan
Published: June 2003

A slightly modified automated commercial synthesis system for preparation of O‐(2‐[18F]fluoroethyl)‐l‐tyrosine (FET), an amino acid tracer for tumor imaging with positron emission tomography, is described. Direct nucleophilic fluorination of [18F]fluoride with 1,2‐di(4‐methylphenylsulfonyloxy)ethane on a quaternary 4‐(4‐methylpiperidinyl)‐pyridinium functionalized polystyrene anion exchange resin gave 1‐[18F]‐2‐(4‐methylphenylsulfonyloxy)ethane, then [18F]fluoroalkylation of l‐tyrosine yielded FET. The overall radiochemical yield with no decay correction was about 8–10%, the whole synthesis time was about 52 min, and the radiochemical purity was above 95%. Copyright © 2003 John Wiley & Sons, Ltd.
Cloudiness changes in Cracow in the 20th Century
Authors: Matuszko Dorota
Published: June 2003

This paper presents the long‐term, annual and diurnal cloud amount values for Cracow (Poland) on the basis of 95‐year records. Cloud data were taken from climatological observations made at the Department of Climatology, Jagiellonian University, in the years 1906–2000.

On the basis of traditional statistical methods, the following values were calculated: average cloudiness (cloud amount), number of cloudless sky occurrences for three climatological terms, daily and yearly averages, and sums of cloudless days. The cloudiness was also analysed from the point of view of its quality. For that purpose, ten specific genera of clouds adopted in the international classification were examined, taking into account the frequency of their occurrence within every month, separately for each of the climatological periods. Copyright © 2003 Royal Meteorological Society
Surface circulation associated with frost in the wet Pampas
Authors: Müller Gabriela V. , Compagnucci Rosa , Nuñez Mario N. , Salles Alejandra
Published: June 2003

The aim of this paper is to make a synoptic–climatic classification of atmospheric circulation in order to obtain synoptic frost‐related patterns in the wet Pampas. Both partial (recorded in 25 to 75% of the meteorological stations) and widespread (recorded in more than 75%) frost events that occurred during the winters (June–July–August) of 1972–83 are included in this study. Frost days are grouped into Neutral (G1), El Niño (G2), and La Niña (G3) years. In addition, the complete dataset, called the total group, is analysed for reference purposes. Each group is analysed using the unrotated and Varimax rotated principal component analysis using the T‐mode approach. Six synoptic situations accounted for 94% of the variance associated with frosts in the area studied.

In general, the principal component score patterns given by the unrotated and rotated components are similar. The biggest difference between unrotated and rotated solutions was in variance redistribution. After rotation, only one of the two possible situations (direct/inverse) of each pattern represented a real synoptic type associated with frost in the wet Pampas. Persistence and location cause temperature drops in the area studied. The most frequent patterns in rotated results are those termed A, B, C* (in G2) and D (in G1 and G3). They are connected with cold anticyclones, which cause advective and/or radiative frosts. The remaining patterns accounted for about 5% of the variance and represent real, though rare, situations, which are important because of their effect on the wet Pampas.

The results obtained for the different groups show that inter‐winter variability of the equatorial Pacific signal produces changes in the frequency of frost‐connected patterns, rather than different patterns for cold events. Copyright © 2003 Royal Meteorological Society
A synoptic‐scale climate analysis of anomalous snow water equivalent over the Northern Great Plains of the USA
Authors: Grundstein Andrew
Published: June 2003

The Northern Great Plains is a region where variations in seasonal snow accumulation can have a dramatic affect on regional hydrology. In the past, one of the problems in studying snow hydrology has been obtaining information of sufficiently high temporal and spatial resolution on the water content of the snowpack. This project used a hybrid climatology of snow water equivalent (SWE) that incorporated both model and observed data. This climatology has a long time series (49 years) and a high spatial resolution (1° × 1°) sufficient for use in a climatic analysis.

The long and complete time series of SWE generated in this project allowed for a comprehensive analysis of the meteorological and climate forcing mechanisms that influence the amount of SWE. The five largest (high SWE) and five smallest SWE (low SWE) accumulations on 1 March were examined. High SWE years received greater snowfall and fewer accumulated melting degree days throughout the season. Large SWE accumulations at the end of the season, however, were not always associated with deep snowpacks early in the season. Also, all five high SWE years had above normal snowfall in February. Years with small or no SWE had below‐average snowfall but greater than average accumulated melting degree days.

A synoptic analysis examined both atmospheric circulation and air mass frequencies to assess impacts on ablation and snowfall. A distinct difference in the frequency of different air mass during high SWE versus low SWE years was evident. High SWE years were characterized by substantially greater intrusions of the coldest and driest air mass type (dry polar). Low SWE years, in contrast, had a greater frequency of more moderate air masses (dry moderate and moist moderate). In years with above average SWE, negative departures in November–December–January–February composite 700 hPa field were evident across the continental USA and indicate a greater frequency of troughing across the study area. Low SWE years were characterized by a ridging pattern that reduced the likelihood of precipitation and may have aided in the intrusion of more moderate air masses. Copyright © 2003 Royal Meteorological Society
Comparison of aerosol and climate variability over Germany and South Africa
Authors: Power Helen C. , Goyal Apurva
Published: June 2003

A radiation‐based model is employed to evaluate seasonal, interannual, and spatial variability within monthly averaged turbidity (the total column amount of aerosol) at eight stations in South Africa and 13 stations in Germany. Germany has a strong seasonal turbidity trend of summer maxima and winter minima. In South Africa the seasonal turbidity trend is weaker, but, on average, turbidity peaks in spring and is lowest in autumn and winter. Over the last several decades, turbidity over Germany has decreased significantly at seven stations. The impacts of the El Chichón and Pinatubo volcanic eruptions are evident in the turbidity signatures over Germany. Four stations in South Africa show long‐term trends in turbidity, but there is no consistent trend. Turbidity in Germany appears to be more influenced by aerosols of non‐local origin than in South Africa, where the aerosol load may be of more local origin. Long‐term monthly averages of Ångström's turbidity coefficient β over Germany range between 0.019 and 0.143, and long‐term annual averages range between 0.064 and 0.116. Over South Africa, turbidity is noticeably lower: long‐term monthly averaged β ranges between 0.004 and 0.071, and the long‐term annually averaged β ranges between 0.013 and 0.047. When averaged across all stations in each of the respective countries, turbidity is, on average, between 2.6 and 5.8 times higher in Germany than in South Africa, depending on the time of year.

The climate of South Africa is clearly more humid than Germany, although both countries have strong seasonal trends in humidity. South Africa has become more humid over the last several decades. The decrease in turbidity at stations in Germany appears to be due to a reduction in aerosol emissions and/or changes in climatic factors other than humidity. Copyright © 2003 Royal Meteorological Society
Precipitation from vertical motion: a statistical diagnostic scheme
Authors: Rose Brian E. J. , Lin Charles A.
Published: June 2003

The relationship between precipitation and atmospheric vertical motion is investigated over the globe. By combining and averaging precipitation rates within small ranges of vertical motion, the mean precipitation rate is found to vary smoothly with vertical motion. The relationship is modelled with a simple function that assumes zero precipitation for subsidence and linearly increasing precipitation for ascending motion. Function parameters are computed from National Centers for Environmental Prediction reanalysis data individually for every grid point and calendar month. Variations in the slope account for geographical and seasonal variations in moisture and other precipitation factors. At each grid point, the scheme diagnoses precipitation rate from a single concurrent value of vertical motion. It is shown to have moderate skill over climatology in predicting mean monthly precipitation. The midlatitudes, oceans and the winter season are favoured. The scheme is designed to extract precipitation fields from a dry general circulation model, based on the simulated vertical motion. Application to climate modelling is discussed. Copyright © 2003 Royal Meteorological Society
Comparison of various precipitation downscaling methods for the simulation of streamflow in a rainshadow river basin
Authors: Salathé Eric P.
Published: June 2003

Global simulations of precipitation from climate models lack sufficient resolution and contain large biases that make them unsuitable for regional studies, such as forcing hydrologic simulations. In this study, the effectiveness of several methods to downscale large‐scale precipitation is examined. To facilitate comparisons with observations and to remove uncertainties in other fields, large‐scale predictor fields to be downscaled are taken from the National Centers for Environmental Prediction–National Center for Atmospheric Research reanalyses. Three downscaling methods are used: (1): a local scaling of the simulated large‐scale precipitation; (2) a modified scaling of simulated precipitation that takes into account the large‐scale wind field; and (3) an analogue method with 1000 hPa heights as predictor.

A hydrologic model of the Yakima River in central Washington state, USA, is then forced by the three downscaled precipitation datasets. Simulations with the raw large‐scale precipitation and gridded observations are also made. Comparisons among these simulated flows reveal the effectiveness of the downscaling methods. The local scaling of the simulated large‐scale precipitation is shown to be quite successful and simple to implement. Furthermore, the tuning of the downscaling methods is valid across phases of the Pacific decadal oscillation, suggesting that the methods are applicable to climate‐change studies. Copyright © 2003 Royal Meteorological Society
Trends in extreme daily rainfall across the South Pacific and relationship to the South Pacific Convergence Zone
Authors: Griffiths G. M. , Salinger M. J. , Leleu I.
Published: June 2003

Daily rainfall records from 22 high‐quality stations located in the South Pacific were analysed, over the common period 1961–2000, in order to assess whether extreme rainfall events have altered in their frequency or magnitude. A comprehensive spatial coverage across the South Pacific was provided, analysing a range of indices of extreme precipitation, which reflect both high rainfall events and drought. Clear spatial patterns emerged in the trends of extreme rainfall indices, with a major discontinuity across the diagonal section of the South Pacific Convergence Zone (SPCZ).

Stations located between 180 and 155°W exhibit a greater number of significant abrupt changes in extreme climate than elsewhere in the South Pacific, and the majority of climatic jumps occur in the 1970s or 1980s (coincident with a displacement northeastward of the diagonal part of the SPCZ and a large local increase in mean annual temperature). Notably, all significant abrupt changes in an extreme rainfall intensity index occurred in the late 1970s or early 1980s, and in every case the index showed an increase in extremity following the change point, regardless of station location. For the stations located south of the SPCZ, this may also be linked to the observed warming since the 1970s. Significant abrupt changes in mean precipitation were also identified around the mid 1940s, for two longer, century‐scale records, which again correspond to a major displacement of the diagonal section of the SPCZ.

An indicator of the diagonal SPCZ position is significantly temporally correlated with an extreme rainfall intensity index, at two locations either side of the diagonal section of the SPCZ, at decadal time scales or longer. This suggests that the displacement of the diagonal portion of the SPCZ on decadal time scales influences not only mean precipitation, but also daily rainfall extremes. Copyright © 2003 Royal Meteorological Society
Recent near‐surface wind changes in the central Mediterranean and Adriatic areas
Authors: Pirazzoli Paolo Antonio , Tomasin Alberto
Published: June 2003

Trends of change in wind direction and velocity during the second part of the last century are examined at 17 coastal Italian stations along a north–south transect over 1000 km long in the central Mediterranean area. Linear regressions and confidence ranges are provided for the frequency and for annual maximum and mean velocities. It appears that wind activity has been mostly decreasing from 1951 to about the mid‐1970s, and increasing after that time. Deviation from the general trend at certain stations is interpreted as possibly depending on local or regional phenomena. The general trends obtained show a positive correlation with temperature changes, whereas they do not correlate with North Atlantic oscillation index variability. Copyright © 2003 Royal Meteorological Society
Interpolymer Complexes of Water‐Soluble Nonionic Polysaccharides with Polycarboxylic Acids and Their Applications
Authors: Nurkeeva Zauresh S. , Mun Grigoriy A. , Khutoryanskiy Vitaliy V.
Published: June 2003

Literature data as well as our own experimental results devoted to the complexation of polycarboxylic acids with various water‐soluble polysaccharides (methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, starch, and dextran) by means of hydrogen bonding are systematized and analyzed. The specific peculiarities of interpolymer complexes based on polysaccharides‐polycarboxylic acids are demonstrated. The perspectives for the application of these interpolymer complexes are considered. It was shown that these materials possess good biocompatibility and adhesive properties. The promising directions for further study of interpolymer complexes between polycarboxylic acids and nonionic polysaccharides as well as existing gaps in the knowledge in this field are pointed out.

Formation of compact IPCs and hydrophilic interpolymer associates.

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Formation of compact IPCs and hydrophilic interpolymer associates.
Antigen Responsive Hydrogels Based on Polymerizable Antibody Fab′ Fragment
Authors: Lu Zheng‐Rong , Kopečková Pavla , Kopeček Jindřich
Published: June 2003

Novel antigen responsive hydrogels were prepared by using polymerizable antibody Fab′ fragment from monoclonal anti‐fluorescein BDC1 antibody (IgG2a). To form Fab′ containing hydrogels, the polymerizable Fab′ fragment was copolymerized with N‐isopropylacrylamide (NIPAAm) and N,N′‐methylenebis(acrylamide) (MBAAm; crosslinker) using redox initiators. The thermosensitivity of the hydrogels decreased with increasing Fab′ fragment content. The antigen responsiveness of the hydrogels depended on the Fab′ content, pH, and temperature. When the hydrogels were alternately exposed to antigens fluorescein (FL) and polyamidoamine dendrimer (PAMAM)‐fluorescein (FD), significant reversible volume changes were observed for the hydrogel containing 50% (w/w) Fab′ fragment at 33.7 and 36.8 °C in acetate buffer (10 mM, pH 5.0), respectively, but not at 27.7 °C or in PBS buffer (10 mM, pH 7.4). No noticeable reversible volume changes were observed with pure PNIPAAm hydrogel and the gel containing 10% (w/w) Fab′ fragment.

Structure of Fab′ containing hydrogels.

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Structure of Fab′ containing hydrogels.
Concurrent Initiation by Air in the Atom Transfer Radical Polymerization of Methyl Methacrylate
Authors: Nanda Ajaya Kumar , Hong Sung Chul , Matyjaszewski Krzysztof
Published: June 2003

The effect of air in atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was studied. Air initiated polymerization was clearly noticed by the appearance of a low molecular weight peak in the synthesis of high molecular weight poly(isobutylene)‐graft‐poly(methyl methacrylate) (Mn = 5.0 × 105 g/mol). The concentration of chains initiated by oxygen (air) was ≈8 × 10−4 mol/L, determined using the Gladstone‐Dale relationship. The tentatively proposed mechanism for air initiated polymerization was supported by kinetic studies. Similar to typical ATRP systems, the rate of air initiated polymerization increased with temperature, [MMA], amount of air, and activity of the catalyst complex. Polymers with lower polydispersities (Mw/Mn = 1.13) were obtained in the presence of Cu(II) as compared to Cu(I) catalyst complex system.

Kinetic plots for the air initiated bulk polymerization of MMA at (•) 20 °C, (▪) 50 °C, and (▴) 90 °C.

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Kinetic plots for the air initiated bulk polymerization of MMA at (•) 20 °C, (▪) 50 °C, and (▴) 90 °C.
Xanthate Mediated Living Polymerization of Vinyl Acetate: A Systematic Variation in MADIX/RAFT Agent Structure
Authors: Stenzel Martina H. , Cummins Lyndal , Roberts G. Evan , Davis Thomas P. , Vana Philipp , Barner‐Kowollik Christopher
Published: June 2003

Eight xanthates were synthesized to induce living free radical polymerization of vinyl acetate. Four compounds, methyl (4‐methoxyphenoxy)carbonothioylsulfanyl acetate, methyl (methoxycarbonothioyl)sulfanyl acetate, methyl (ethoxycarbonothioyl)sulfanyl acetate and methyl (isopropoxycarbonothioyl)sulfanyl acetate were identified as suitable MADIX/RAFT agents, yielding low polydispersity (PDI < 1.2) poly(vinyl acetate) of molecular weights exceeding 5 × 104 g · mol−1. All suitable MADIX/RAFT agents exhibited extended periods of inhibition (0.3 h < tinh < 10 h) and moderate rate retardation. The ability of these compounds to control vinyl acetate polymerization can be correlated with the electron density on the central carbon atom of the xanthate. Electrospray ionization mass spectrometric analysis was performed to complete the investigation on the new MADIX/RAFT agents.

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Block Copolymers from Organomodified Siloxane‐Containing Macroinitiators by Atom Transfer Radical Polymerization
Authors: Strissel Christine , Matyjaszewski Krzysztof , Nuyken Oskar
Published: June 2003

Alternating copolymers of 1,3‐diisopropenylbenzene and 1,1,3,3‐tetramethyldisiloxane were synthesized by hydrosilylation–polyaddition. These linear copolymers were functionalized at both ends with 2‐bromoisobutyryl or benzyl chloride moieties. Subsequently, the obtained organomodified siloxane‐containing macroinitiators were successfully used for the preparation of ABA‐type block copolymers by atom transfer radical polymerization (ATRP) of styrene and tert‐butyl acrylate. The high chain‐end functionality of the macroinitiators was confirmed by 1H NMR analysis of the macroinitiators and GPC measurements of the obtained ABA‐type block copolymers. The macroinitiator peaks disappeared in GPC traces after ATRP, and the obtained block copolymers showed a significantly narrower molecular‐weight distribution than the macroinitiators.

Synthesis of ABA‐type block copolymers by means of ATRP using organomodified siloxane‐containing, benzyl chloride functionalized macroinitiators.

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Synthesis of ABA‐type block copolymers by means of ATRP using organomodified siloxane‐containing, benzyl chloride functionalized macroinitiators.
Alternating Copolymers of Ethylene and Diolefins Containing Pendent Functional Groups
Authors: Williamson Alex , Fink Gerhard
Published: June 2003

The catalyst [Me2C(Flu)(3‐MeCp)ZrCl2] (1), activated by MAO, was used for the copolymerization of ethylene and 1,7‐octadiene (OD) to form copolymers with pendent double bonds. The properties of the copolymers were strongly dependent on the purity of the comonomer. Formation of ethylene‐rich sequences and increased levels of crosslinking were observed with highly purified 1,7‐octadiene. Catalysts 1 and [Me2Si(Flu)2ZrCl2] (2), activated by MAO, were used for the copolymerization of ethylene and 7‐methyl‐1,6‐octadiene (MOD). In both cases, alternating copolymers were formed with unreacted pendent double bonds. The triad distributions were analyzed by Markovian first‐ and second‐order statistics. Copolymers produced by catalyst 2 were significantly more alternating than copolymers produced by catalyst 1 despite the fact that catalyst 2 is highly symmetrical. Epoxidation of pendent double bonds was examined.

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Differential Scanning Calorimetry (DSC) for Interdiffusion Studies in PVC/PnBMA Blend: A Quantitative Analysis
Authors: Dlubek Günter , Pompe Gisela , Pionteck Jürgen , Janke Andreas , Kilburn Duncan
Published: June 2003

Differential scanning calorimetry (DSC) was used to study interdiffusion in an initially demixed blend, prepared as particle‐matrix system of the intrinsic miscible polymers poly(vinyl chloride) (PVC, particle, 30 wt.‐%) and poly(butyl methacrylate) (PnBMA, matrix, 70 wt.‐%) during isothermal annealing at 110 °C. A detailed interpretation of the experimental DSC curves was realised using a core‐shell model for the particle matrix system, a calculated concentration‐distance profile across the particle‐matrix interface, and a parameterised concentration dependent curve for the heat flow of mixed blend states derived from experiments. The calculated curves were fitted to the experimental data by variation of the concentration dependence of the diffusion coefficient and its concentration averaged value. Both parameters determine the concentration‐distance profile. From the evolution of the concentration‐distance profile with the annealing time the parameters of the interdiffusion kinetics were analysed. The growth of the mean width of the interfacial phase with time follows a power law with an exponent of k = 0.42. A coefficient of mutual diffusion, $\mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\smile$}}\over D}$, increasing linearly by one order of magnitude from pure PVC to PnBMA, and its concentration averaged value of $\mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\smile$}}\over D} _{{\rm av}} = 2.0 \times 10^{ - 18}$ m2/s were concluded from the experiments.

Half width parameter \sigma _{{\rm av}}^* of the interphase for the initially phase‐separated blend PVC/PnBMA = 70/30 wt.‐% vs. the annealing time ta at 110 °C.

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Half width parameter \sigma _{{\rm av}}^* of the interphase for the initially phase‐separated blend PVC/PnBMA = 70/30 wt.‐% vs. the annealing time ta at 110 °C.
Nanostructure Evolution of Homogeneous Poly(ethylene‐co‐1‐octene) as a Function of Strain
Authors: Stribeck Norbert , Androsch René , Funari Sérgio S.
Published: June 2003

Polyolefin elastomers with varying 1‐octene content and different thermal history are studied by wide‐angle X‐ray scattering (WAXS) and small‐angle X‐ray scattering (SAXS) during drawing and after relaxation. The multidimensional chord distribution function (CDF) reveals the nanostructure made from crystallites in the amorphous matrix. Both lamellae and granular crystals are found. Lamellae do not form stacks. The SAXS peak is observed because each lamella is covered by an amorphous layer of well‐defined thickness. Arrangement, rotation, fine chain slip and failure of the domains are directly observed as a function of elongation. During straining and relaxation a well oriented macrolattice with colloidal dimensions but short‐ranging order is formed. Two processes are generating microfibrils, namely (1) arrangement of granular crystallites, and (2) irreversible disruption of lamellae (coarse slip) followed by arrangement of their fragments. The second process stabilizes the colloidal lattice permanently. The higher the comonomer content, the later the irreversible process starts. Quenching from the melt shifts the onset to lower deformation. Deformation of microfibrils is not homogeneous. Instead, there is a limiting long period that cannot be exceeded without disruption. It is related to the position of the maximum in the SAXS pattern (which is almost constant).

Long periods in the CDF z(r12, r3) of an ethylene‐octene block copolymer after relaxation from drawing.

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Long periods in the CDF z(r12, r3) of an ethylene‐octene block copolymer after relaxation from drawing.
The Photoinduced Birefringence in Thick Films of Chiral Azodye Copolymers
Authors: Kozlovsky Mikhail V. , Lazarev Vladimir V.
Published: June 2003

The photoinduced birefringence, Δnind, in 19–35 μm thick films has been studied for two series of chiral photochromic liquid crystalline side chain copolymers. The birefringence measured is induced by excitation of the n‐π* band only. The Δnind value induced in 10 min is linear upon concentration of dye moieties but achieves saturation with increase of illumination intensity. Evolution of the birefringence can be described by double exponent growth; the faster exponent is the same for both copolymer series and should relate to the photoselection process, while the slower one should relate mainly to photo‐orientation and differs strongly dependent on chemical structure of photochromic groups. The different behaviour of two copolymer series during the growth governed by the second exponent is interpreted in terms of the “frictional model”. Due to elevated thickness of the films, rather moderate Δnind values result in huge phase retardation up to 270° and more. The materials are promising therefore for holography applications.

Chemical structure of the synthesised chiral photochromic copolymers.

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Chemical structure of the synthesised chiral photochromic copolymers.
Holomorphic Banach bundles on finite–dimensional q–complete complex manifolds
Authors: Ballico Edoardo
Published: June 2003

Let X be a q–complete complex manifold (resp. finite–dimensional Stein space) and E a holomorphic vector bundle on X with fibers isomorphic to a Banach space. Here we prove that Hi(X, E) = 0 for every i > q (resp. i > 0).
Monotone variations of the first eigenvalue for doubly connected domains
Authors: Chu Chie–Ping , Chy Fwu Chih
Published: June 2003

The first Dirichlet eigenvalue for the Laplace operator of a doubly connected plane domain varies with the relative position of the inner hole. Under certain mild hypothesis it decreases as the two boundary curves get closer along some specific direction. We made this observation by analyzing level curves and rearrangement technique.
Positive solutions of a higher order neutral differential equation
Authors: Graef John R. , Qian Chuanxi , Yang Bo
Published: June 2003

In this paper, we consider the higher order neutral delay differential equation

where p : [0, ∞) → (0, ∞) is a continuous function, r > 0 and σ > 0 are constants, and n > 0 is an odd integer. A positive solution x(t) of Eq. (*) is called a Class–I solution if y(t) > 0 and y′(t) < 0 eventually, where y(t) = x(t) – x(t – r). We divide Class–I solutions of Eq. (*) into four types. We first show that every positive solution of Eq. (*) must be of one of these four types. For three of these types, a necessary and sufficient condition is obtained for the existence of such solutions. A necessary condition for the existence of a solution of the fourth type is also obtained. The results are illustrated with examples.
On the Cauchy problem for second order strictly hyperbolic equations with non–regular coefficients
Authors: Hirosawa Fumihiko
Published: June 2003

In this paper we shall consider some necessary and sufficient conditions for well–posedness of second order hyperbolic equations with non–regular coefficients with respect to time. We will derive some optimal regularities for well–posedness from the intensity of singularity to the coefficients by WKB representation of the solution and some counter examples which are constructed by using ideas of Floquet theory.
Exceptional curves on Del Pezzo surfaces
Authors: Knutsen Andreas Leopold
Published: June 2003

We classify all cases of exceptional curves on Del Pezzo surfaces, which turn out to be the smooth plane curves and some other cases with Clifford dimension 3. Moreover, the property of being exceptional holds for all curves in the complete linear system. We use this study to extend the results of Pareschi [17] on the constancy of the gonality and Clifford index of smooth curves in a complete linear system on Del Pezzo surfaces of degrees ≥ 2 to the case of Del Pezzo surfaces of degree 1, where we explicitly classify the cases where the gonality and Clifford index are not constant.
Local properties of Colombeau generalized functions
Authors: Oberguggenberger Michael , Pilipovic Stevan , Scarpalezos Dimitris
Published: June 2003

Generalized functions as mappings defined on the set of generalized points are considered. Local properties of generalized functions, singular support and various types of 𝒢∞–regularity are analyzed. Suppleness and non–flabbyness are proved. Necessary and sufficient conditions on generalized functions extendable out of an open set, are given. Colombeau microfunctions are introduced.
Exfoliated Polylactide/Clay Nanocomposites by In‐Situ Coordination–Insertion Polymerization
Authors: Paul Marie‐Amélie , Alexandre Michaël , Degée Philippe , Calberg Cédric , Jérôme Robert , Dubois Philippe
Published: June 2003

Poly(L‐lactide)/layered aluminosilicate nanocomposites were synthesized in bulk by ring‐opening polymerization in the presence of two organo‐modified montmorillonites. When the organo‐modifier consisted of an ammonium cation bearing primary hydroxyl groups, polymerization was initiated by the alcohol functions after adequate activation. The growing polymer chains were directly “grafted” onto the clay surface through the hydroxyl‐functionalized ammonium cations yielding exfoliated nanocomposites with enhanced thermal stability.

TEM image of a fully exfoliated Cloisite®30B‐based nanocomposite, showing delamination of the silicate layers.

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TEM image of a fully exfoliated Cloisite®30B‐based nanocomposite, showing delamination of the silicate layers.
Multicomb Polymeric Supramolecules and Their Self‐Organization: Combination of Coordination and Ionic Interactions
Authors: Valkama Sami , Lehtonen Olli , Lappalainen Kristian , Kosonen Harri , Castro Pascal , Repo Timo , Torkkeli Mika , Serimaa Ritva , ten Brinke Gerrit , Leskelä Markku , Ikkala Olli
Published: June 2003

Several alkyl side chains are bonded to each polymeric repeat unit using both coordinated ligands and electrostatically bound counterions to directly control the interface curvature of the self‐organized structures. 2,6‐Bis(octylaminomethyl)pyridine is Zn‐coordinated to poly(4‐vinylpyridine) (P4VP) with dodecylbenzenesulfonate (DBS) counterions, leading to multicomb polymeric supramolecules, poly[(4VP)Zn(2,6‐bis(octylaminomethyl)pyridine)(DBS)2]. Coordination is evidenced by infrared spectroscopy and visualized by quantum chemical calculations. The amorphous hexagonal self‐organized structures are characterized using X‐ray measurements.

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Structural Characterization of Biocidal Oligoguanidines
Authors: Feiertag Petra , Albert Martin , Ecker‐Eckhofen Eva‐M. , Hayn Gertraud , Hönig Helmut , Oberwalder Hanns W. , Saf Robert , Schmidt Andreas , Schmidt Oskar , Topchiev Dmitrij
Published: June 2003

Oligomeric guanidines can be obtained by polycondensation of guanidine hydrochloride and 1,2‐bis(2‐aminoethoxy)ethane. A comparative MALDI‐TOF mass spectrometry/NMR spectroscopy study with a 13C‐labeled sample enabled the unambiguous analysis of a guanidine‐based polymer. Among the four major product series unprecedented macrocyclic compounds were detected. The minimum inhibition concentrations for four different microorganisms were determined, showing excellent biocidal activities.

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Synthesis of Poly(ethylene oxide)s Bearing Functional Groups along the Chain
Authors: Dimitrov Ivaylo V. , Berlinova Iliyana V.
Published: June 2003

Well‐defined poly(ethylene oxide)s (PEOs) bearing reactive sites regularly distributed along the chain have been synthesized by the polycondensation of PEO containing a central tertiary amino group with dichloromethane, followed by quaternization with suitable reagents to obtain polyzwitterionic or cationic PEOs with alkyl, allyl, or fluorocarbon pendant groups. The pendant allyl groups have been converted into primary amino groups by reaction with 2‐aminoethanethiol hydrochloride to obtain polyamino‐functionalized PEO.

Polyfunctional PEOs bearing different pendant groups.

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Polyfunctional PEOs bearing different pendant groups.
A Self‐Assembling Polythiophene Functionalised with a Cysteine Moiety
Authors: Mucci Adele , Parenti Francesca , Schenetti Luisa
Published: June 2003

A new copolymer bearing a cysteine moiety, designed for molecular interaction, metal‐ion detection, and chiral recognition, was synthesised starting from the dibromo derivative of methyl N‐(tert‐butoxycarbonyl)‐S‐thien‐3‐ylcysteinate and distannylthiophene through a Stille coupling reaction. UV‐vis spectroscopy, circular dichroism, NMR spectroscopy, and gel permeation chromatography analyses evidenced that this polymer is able to form self‐assembling structures, through the formation of a hydrogen‐bond network, not only in the solid state but also in solution.

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Synthesis of Well‐Defined Rod‐Coil‐Rod Polyhexylisocyanate‐block‐polystyrene‐block‐polyhexylisocyanate via One‐Pot Anionic Polymerization
Authors: Ahn Jun‐Hwan , Lee Jae‐Suk
Published: June 2003

A rod‐coil‐rod block copolymer, polyhexylisocyanate‐block‐polystyrene‐block‐polyhexylisocyanate, of controlled molecular weight was synthesized quantitatively via living anionic polymerization using potassium naphthalenide in the presence of sodium tetraphenylborate. The use of K+ as the counterion for the polymerization of styrene, and Na+ (NaBPh4) for the polymerization of isocyanate leads to the formation of a well‐controlled novel triblock copolymer.

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Polymer Bonded Ferrite Materials as EMC Components
Authors: Töpfer J. , Pawlowski B. , Gräbner F.
Published: June 2003

Polymer bonded ferrites composed of a mixture of Mn‐Zn ferrites or Ni‐Zn ferrites in a polymer binder (PE, PA) were prepared and tested as electromagnetic‐wave absorbing materials. Test samples and cases were prepared by hot or injection molding. Permeability spectra show loss contributions in the frequency range 100‐1000 MHz. Absorption measurements of injection molded polymer‐ferrite cases display a 3‐5 dB better attenuation characteristics compared to graphite‐loaded polyamide housings.
Potentialunterstützte Herstellung von Metall‐Keramik‐Verbundschichten
Authors: Knote A. , Schindler U. , Krüger H.‐G. , Kern H.
Published: June 2003

Eine Möglichkeit zur Herstellung von homogenen Metall‐Keramik‐Kompositschichten mit einem hohen Keramikanteil bis zu 60 Vol.‐% soll in dieser Arbeit vorgestellt werden. Diese Methode besteht aus einer Kombination aus elektrophoretischer und galvanischer Abscheidung in aufeinanderfolgenden Schritten. Dabei wird zunächst eine yttriumstabilisierte Zirkonoxidschicht (Tosoh TZ‐8Y) elektrophoretisch auf einem ferritischen Stahl erzeugt, und dann bei 1100 °C zu einer offenporösen Schicht versintert. Im nächsten Schritt wird elektrolytisch Nickel in die Poren der Schicht abgeschieden. Durch eine finale thermische Behandlung war es möglich, die Anbindung der Kompositschicht an das Substrat durch Diffusion der Metallkomponenten zu verbessern.