bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure‐property investigations on a laser beam welded dissimilar joint of aluminium AA6056 and titanium Ti6Al4V for aeronautical applications. Part II: Resistance to fatigue crack propagation and fracture
Authors: Vaidya W. V. , Horstmann M. , Ventzke V. , Petrovski B. , Koçak M. , Kocik R. , Tempus G.
Published: October 2009

Investigations were continued on the dissimilar laser beam welds of AA6056 and Ti6Al4V, fabricated by inserting Ti‐sheet into the profiled Al‐sheet and melting AA6056 alone. By using microstructure, hardness and strength as the criteria, sites exhibiting non‐uniform microstructure and localized plastic deformation due to strength mismatch were investigated in two orientations: • crack parallel to the weld and • crack perpendicular to the weld for fatigue crack propagation and fracture toughness at room temperature. Effect of temper of AA6056 on these properties was studied for two conditions; welding in T4 followed by post weld heat treatment T6, and welding in T6 and naturally aged for a defined period. The orientation “crack parallel to the weld” was investigated in 3 locations on the side of AA6056: the interface and the two changeovers on the Al‐side. Firstly, between the fusion zone and the heat affected zone (3 mm from the interface) and secondly, between (primary) heat affected zone and towards the base material (7 mm from the interface). Although brittle intermetallic TiAl3 had been formed at the interface, uncontrolled separation or debonding at the interface was not observed. Insofar the bond quality of the weld was good. However, the ranking of interface was the lowest since fatigue crack propagation was relatively faster than that in the fusion zone and heat affected zone, and fracture toughness was low. Therefore, unstable fatigue crack propagation is observed when the crack propagates perpendicular to the weld from AA6056 towards Ti6Al4V. The results have shown that the dissimilar joints exhibit improved performance when laser beam welded in the T6 condition.
Bone‐like apatite‐coated chitosan scaffolds: Characterization and osteoblastic activity
Authors: Aday Sezin , Gümüşderelioğlu Menemşe
Published: October 2009

In this study, porous scaffolds were prepared from chitosan (2% w/v in acetic acid and deacetylation degree: DD > 85%) by freeze‐drying method, and freshly lyophilized scaffolds were stabilized with ethanol solutions. Bone‐like apatite formation on chitosan scaffolds was achieved by immersing the scaffolds into a novel concentrated simulated body fluid (10× SBF‐like solution) for different periods, i.e., 6 and 24 h. Scanning electron microscope views showed that the 6‐h treatment in 10× SBF‐like solution led to the formation of calcium phosphate nucleation sites on chitosan scaffolds, whereas the apatite particles showed characteristic cauliflower‐like morphology at the end of 24‐h treatment. X‐ray diffraction results supported the fact that mineral phase was made of hydroxyapatite. Osteogenic activities of untreated and SBF‐treated chitosan scaffolds were examined by preosteoblastic MC3T3 cell culture studies. The mitochondrial activity test showed that apatite‐coated scaffolds stimulated cell proliferation compared with uncoated scaffolds. Alkaline phosphatase and osteocalcine levels indicated that the differentiation of the cells on all scaffolds increased significantly from 15th day of culture to the 21th day of culture, especially for the cells on 24‐h SBF‐treated scaffolds. The results of this study indicated that 10× SBF‐like solution‐treated chitosan scaffolds may be evaluated for bone tissue engineering. POLYM. COMPOS., 31:1418–1426, 2010. © 2009 Society of Plastics Engineers
Placental growth hormone and growth hormone binding protein are first trimester maternal serum markers of Down syndrome
Authors: Christiansen Michael
Published: October 2009

Background

Placental growth hormone (PGH) is synthesised by the placenta, and its function is modulated by growth hormone binding protein (GHBP). The potential of PGH and GHBP as maternal serum screening markers for Down syndrome (DS) was examined.

Materials and methods

Maternal serum concentrations of PGH and GHBP were determined by ELISA in 74 DS and 261 control pregnancies in gestational week 8+0 to 13+4. Log10 MoM distributions of the markers were established. The performance of DS screening was estimated by Monte Carlo simulation.

Results

PGH log10 MoM (SD) was decreased (p < 0.001) to −0.201 (0.373) and GHBP log10 MoM to −0.116 (0.265) (p = 0.04), in DS pregnancies (n = 34) in week 8+0 to 10+0. In week 10+1 to 13+4, neither PGH (p = 0.16) nor GHBP (p = 0.13) was reduced in DS pregnancies. The detection rate (DR) for PGH in screening for DS in week 8+0 to 10+0 was 39% for a false positive rate (FPR) of 5%; increasing to 72% in combination with PAPP‐A + hCGβ. PGH + GHBP in combination with PAPP‐A + hCGβ + nuchal translucency (NT) (CUB test) had a DR of 91% compared with 80% for the CUB test.

Conclusion

PGH and GHBP are early first trimester maternal serum markers for DS [Correction made here after initial online publication]. Copyright © 2009 John Wiley & Sons, Ltd.
The ligand‐binding b′ domain of human protein disulphide‐isomerase mediates homodimerization
Authors: Wallis Anne Katrine , Sidhu Ateesh , Byrne Lee J. , Howard Mark J. , Ruddock Lloyd W. , Williamson Richard A. , Freedman Robert B.
Published: October 2009

Purified preparations of the recombinant b′x domain fragment of human protein‐disulphide isomerase (PDI), which are homogeneous by mass spectrometry and sodium dodecyl sulfate polyacrylamide gel electrophoresis, comprise more than one species when analyzed by ion‐exchange chromatography and nondenaturing polyacrylamide gel electrophoresis. These species were resolved and shown to be monomer and dimer by analytical ultracentrifugation and analytical size‐exclusion chromatography. Spectroscopic properties indicate that the monomeric species corresponds to the “capped” conformation observed in the x‐ray structure of the I272A mutant of b′x (Nguyen, Wallis, Howard, Haapalainen, Salo, Saaranen, Sidhu, Wierenga, Freedman, Ruddock, and Williamson, J Mol Biol 2008;383:1144‐1155) in which the x region binds to a hydrophobic patch on the surface of the b′ domain; conversely, the dimeric species has an “open” or “uncapped” conformation in which the x region does not bind to this surface. The larger bb′x fragment of human PDI shows very similar behavior to b′x and can be resolved into a capped monomeric species and an uncapped dimer. Preparations of recombinant b′ domain of human PDI and of the bb′ domain pair are found exclusively as dimers. Full‐length PDI is known to comprise a mixture of monomeric and dimeric species, whereas the isolated a, b, and a′ domains of PDI are found exclusively as monomers. These results show that the b′ domain of human PDI tends to form homodimers—both in isolation and in other contexts—and that this tendency is moderated by the adjacent x region, which can bind to a surface patch on the b′ domain.
The crystal structure of a TIR domain from Arabidopsis thaliana reveals a conserved helical region unique to plants
Authors: Chan Siew Leong , Mukasa Takashi , Santelli Eugenio , Low Lieh Yoon , Pascual Jaime
Published: October 2009

Plants use a highly evolved immune system to exhibit defense response against microbial infections. The plant TIR domain, together with the nucleotide‐binding (NB) domain and/or a LRR region, forms a type of molecule, named resistance (R) proteins, that interact with microbial effector proteins and elicit hypersensitive responses against infection. Here, we report the first crystal structure of a plant TIR domain from Arabidopsis thaliana (AtTIR) solved at a resolution of 2.0 Å. The structure consists of five β‐strands forming a parallel β‐sheet at the core of the protein. The β‐strands are connected by a series of α‐helices and the overall fold mimics closely that of other mammalian and bacterial TIR domains. However, the region of the αD‐helix reveals significant differences when compared with other TIR structures, especially the αD3‐helix that corresponds to an insertion only present in plant TIR domains. Available mutagenesis data suggest that several conserved and exposed residues in this region are involved in the plant TIR signaling function.
Disulfide conformation and design at helix N‐termini
Authors: Indu S. , Kumar Senthil T. , Thakurela Sudhir , Gupta Mansi , Bhaskara Ramachandra M. , Ramakrishnan C. , Varadarajan Raghavan
Published: October 2009

To understand structural and thermodynamic features of disulfides within an α‐helix, a non‐redundant dataset comprising of 5025 polypeptide chains containing 2311 disulfides was examined. Thirty‐five examples were found of intrahelical disulfides involving a CXXC motif between the N‐Cap and third helical positions. GLY and PRO were the most common amino acids at positions 1 and 2, respectively. The N‐Cap residue for disulfide bonded CXXC motifs had average (ϕ,ψ) values of (−112 ± 25.2°, 106 ± 25.4°). To further explore conformational requirements for intrahelical disulfides, CYS pairs were introduced at positions N‐Cap‐3; 1,4; 7,10 in two helices of an Escherichia coli thioredoxin mutant lacking its active site disulfide (nSS Trx). In both helices, disulfides formed spontaneously during purification only at positions N‐Cap‐3. Mutant stabilities were characterized by chemical denaturation studies (in both oxidized and reduced states) and differential scanning calorimetry (oxidized state only). All oxidized as well as reduced mutants were destabilized relative to nSS Trx. All mutants were redox active, but showed decreased activity relative to wild‐type thioredoxin. Such engineered disulfides can be used to probe helix start sites in proteins of unknown structure and to introduce redox activity into proteins. Conversely, a protein with CYS residues at positions N‐Cap and 3 of an α‐helix is likely to have redox activity. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Influence of temperature on the synthesis of thiol‐stabilized CdTe nanoparticles in aqueous solutions
Authors: Khalavka Y. , Mingler B. , Friedbacher G. , Okrepka G. , Shcherbak L. , Panchuk O.
Published: October 2009

We have investigated the evolution of thiol‐capped cadmium telluride nanocrystals prepared in aqueous solutions at low and room temperature followed by heating at 50–100 °C. The UV–visible absorption spectra, as well as transmission electron microscopy, atomic force microscopy, and dynamic light scattering observations made it possible to reveal differences in size and structure originating from different heating temperatures. It was shown that minimization of the nucleation process temperature provided formation of larger nanoparticles than at higher temperatures.
Growth of ultralong ZnO microwire and its application in isolatable and flexible piezoelectric strain sensor
Authors: Sun Kaitong , Zhang Heqiu , Hu Lizhong , Yu Dongqi , Qiao Shuangshuang , Sun Jingchang , Bian Jiming , Chen Xi , Zhang Lingxuan , Fu Qiang , Zhao Ziwen
Published: October 2009

Ultralong ZnO piezoelectric‐fine‐wires (PFWs) with a perfect hexagonal structure have been prepared by an upstream growing chemical vapor deposition (CVD) method. Furthermore, isolatable and flexible piezoelectric strain sensors based on individual ZnO PFWs have been fabricated by a simple and reliable technique. The whole device was fully packaged by epoxy polymeric resin (EPR). The I–V characteristic of the isolatable sensor is highly sensitive to the strain applied on it, which was well interpreted in terms of variation in Schottky barrier height (SBH) caused by strain induced band structure change and piezoelectric effect. The sensor exhibited excellent stability and fine reversibility, and a remarkably high gauge factor up to 1010 had been achieved. It is expected that the isolatable and flexible piezoelectric strain sensor demonstrated here will have applications in detection of external mechanical forces, as well as electromechanical switch with a high ON/OFF ratio.
Polarization of eigenmodes in laser diode waveguides on semipolar and nonpolar GaN
Authors: Rass Jens , Wernicke Tim , Scheibenzuber Wolfgang G. , Schwarz Ulrich T. , Kupec Jan , Witzigmann Bernd , Vogt Patrick , Einfeldt Sven , Weyers Markus , Kneissl Michael
Published: October 2009

Recent calculations of the eigenmodes in waveguides grown on semipolar GaN suggest that the optical polarization of the emitted light as well as the optical gain depends on the orientation of the resonator. Our measurements on separate confinement heterostructures on semipolar (11$ \bar 2 $2) and (10$ \bar 1 $2) GaN show that for laser resonators along the semipolar [11$ \bar 2 \bar 3 $] and [0$ \bar 1 $11] directions (i.e. the projection of the c‐axis onto the plane of growth) the threshold for amplified spontaneous emission is lower than for the nonpolar direction and that the stimulated emission is linearly polarized as TE mode. For the waveguide structures along the nonpolar [1$ \bar 1 $00] or [11$ \bar 2 $0] direction on the other hand, birefringence and anisotropy of the optical gain in the plane of growth leads not only to a higher threshold but alsoto a rotation of the optical polarization which is not any more TE‐ or TM‐polarized but influenced by the ordinary and extraordinary refractive index of the material. We observe stimulated emission into a mode which is linearly polarized in extraordinarydirection nearly parallel to the c‐axis. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid drug detection in oral samples by porous silicon assisted laser desorption/ionization mass spectrometry
Authors: Lowe Rachel D. , Guild Georgia E. , Harpas Peter , Kirkbride Paul , Hoffmann Peter , Voelcker Nicolas H. , Kobus Hilton
Published: October 2009

The demand for analysis of oral fluid for illicit drugs has arisen with the increased adoption of roadside testing, particularly in countries where changes in legislation allow random roadside testing of drivers for the presence of a palette of illicit drugs such as methamphetamine (MA), 3,4‐methylenedioxymethamphetamine (MDMA) and Δ9‐tetrahydrocannabinol (THC). Oral samples are currently tested for such drugs at the roadside using an immunoassay‐based commercial test kit. Positive roadside tests are sent for confirmatory laboratory analysis, traditionally by means of gas chromatography/mass spectrometry (GC/MS). We present here an alternative rapid analysis technique, porous silicon assisted laser desorption/ionization time‐of‐flight mass spectrometry (pSi LDI‐MS), for the high‐throughput analysis of oral fluids. This technique alleviates the need for sample derivatization, requires only sub‐microliter sample volumes and allows fast analysis (of the order of seconds). In this study, the application of the technique is demonstrated with real samples from actual roadside testing. The analysis of oral samples resulted in detection of MA and MDMA with no extraction and analysis of THC after ethyl acetate extraction. We propose that, subject to miniaturization of a suitable mass spectrometer, this technique is well suited to underpin the deployment of oral fluid testing in the clinic, workplace and on the roadside. Copyright © 2009 John Wiley & Sons, Ltd.
Precursor ion scans for the targeted detection of stable‐isotope‐labeled peptides
Authors: Colzani Mara , Bienvenut Willy V. , Faes Eveline , Quadroni Manfredo
Published: October 2009

Stable isotope labels are routinely introduced into proteomes for quantification purposes. Full labeling of cells in varying biological states, followed by sample mixing, fractionation and intensive data acquisition, is used to obtain accurate large‐scale quantification of total protein levels. However, biological processes often affect only a small group of proteins for a short time, resulting in changes that are difficult to detect against the total proteome background. An alternative approach could be the targeted analysis of the proteins synthesized in response to a given biological stimulus. Such proteins can be pulse‐labeled with a stable isotope by metabolic incorporation of ‘heavy’ amino acids. In this study we investigated the specific detection and identification of labeled proteins using acquisition methods based on Precursor Ion Scans (PIS) on a triple‐quadrupole ion trap mass spectrometer. PIS‐based methods were set to detect unique immonium ions originating from labeled peptides. Different labels and methods were tested in standard mixtures to optimize performance. We showed that, in comparison with an untargeted analysis on the same instrument, the approach allowed a several‐fold increase in the specificity of detection of labeled proteins over unlabeled ones. The technique was applied to the identification of proteins secreted by human cells into growth media containing bovine serum proteins, allowing the preferential detection of labeled cellular proteins over unlabeled bovine ones. However, compared with untargeted acquisitions on two different instruments, the PIS‐based strategy showed some limitations in sensitivity. We discuss possible perspectives of the technique. Copyright © 2009 John Wiley & Sons, Ltd.
Inoperability input‐output modeling (IIM) of disruptions to supply chain networks
Authors: Wei Hairui , Dong Ming , Sun Shuyu
Published: October 2009

In this paper, the Inoperability Input‐Output Model (IIM) is deployed for assessing the impacts of disruptive events on supply chain networks under an unsafe environment. The IIM for supply chain networks has been proposed, based on the original IIM used in macro‐economics. A new method called the OWA (Ordered Weighted Averaging) Operator has been formulated to evaluate the interdependency matrix, a key component of the IIM. Similar to the capability of the basic IIM to describe the propagation impacts of disruptions to macroeconomic systems, the IIM for supply chain networks is capable of describing the propagation effects of disruptions to interdependent supply chain components. IIM assesses the impacts of disruptions to supply chain networks with “inoperability” and “economic losses” metrics, which can provide helpful insights for risk management of supply chain networks. An example supply chain network is used to illustrate the application of IIM for systemic risk assessment of supply chains under an unsafe environment. A risk mitigation strategy by increasing the number of suppliers has been considered to reduce the adverse effects caused by the supply reduction of the single secondary supplier in the example supply chain network. In addition, a simulation model integrated with Monte Carlo simulation method has been developed to validate the accuracy of the IIM for supply chain. The example shows that the application of IIM can provide useful guidance toward supply chain risk management or mitigation strategies and it could also be used to test the effectiveness of these strategies. © 2009 Wiley Periodicals, Inc. Syst Eng
Evolving the INCOSE reference curriculum for a graduate program in systems engineering
Authors: Squires Alice , Cloutier Robert
Published: October 2009

This paper suggests an evolution to the graduate level systems engineering curriculum framework documented in an International Council on Systems Engineering (INCOSE) report in October of 2007 [Jain and Verma, INCOSE‐PP‐2007‐001‐01, Seattle, WA, 2007]. This evolution leverages the International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) 15288 Systems and Software Engineering—System Life Cycle Processes standard [ISO/IEC 15288, International Organization for Standardization, Geneva, 2008] as a guide. The evolved framework is presented and consists of six levels of course categories: prerequisite, introductory, technical system life cycle processes, project planning system life cycle processes, infrastructure processes and other broad areas, and capstone courses. Next, 18 systems engineering centric online masters degrees offered by 17 distinct universities are identified as part of a growing base of graduate level systems engineering degrees offered globally through distance education. Specific examples for applying the framework using three of the universities that provide online systems engineering masters programs globally are included. © 2009 Wiley Periodicals, Inc.
Credit markets: Tumultuous and opportunistic— navigating the shifting terrain of debt markets
Authors: Wittlin Roger
Published: October 2009

Historic events battered both the financial markets and the real economy throughout 2008 and the first quarter of 2009. On Wall Street, the destruction was most evident through the bankruptcy of Lehman Brothers; the acquisitions of Bear Stearns, Merrill Lynch, and Wachovia; and the implosions of AIG, Fannie Mae, and Freddie Mac. And Main Street wasn't spared, as the declines in home prices, large federal involvement in the banking and the automobile industries, a rapid rise in unemployment, and the explosion of the U.S. federal budget deficit have shaped millions of lives and will dramatically alter the country's economic future. © 2009 Wiley Periodicals, Inc.
Effects of waste ground rubber tire powder (WGRT) and chemical blowing agent content on the cell morphology and physicomechanical properties of injection‐molded polypropylene/WGRT foams
Authors: Xin Zhen Xiang , Zhang Zhen Xiu , Pal Kaushik , Kang Dong Jin , Lee Sung Hyo , Kim Jin Kuk
Published: October 2009

Microcellular polypropylene (PP)/WGRT blends, a new outlet for the recycling of waste tire rubber, were prepared in an injection‐molding process by using a chemical blowing agent. The effects of WGRT content and chemical blowing agent content on the density, cell morphology, and physicomechanical properties of the foamed PP/WGRT blends were investigated. The foam morphologies were characterized in terms of void fraction, average cell size, and cell density. The results indicated that both the WGRT and the blowing agent content had huge effects on the cell morphology and tensile properties of the PP/WGRT foams. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Robust and distributed control of a smart blade
Authors: Rice Justin K. , Verhaegen Michel
Published: October 2009

For the next generation of larger off‐shore wind turbines, it has been suggested to use feedback to actively control the blade vibrations, thus decreasing fatigue damage and increasing the life of the machine. Because of both practical engineering difficulties and fundamental control theoretic limitations, it seems that individual pitch actuation may not be well suited for this type of control, prompting researchers to investigate other forms, such as tip actuation and the ‘smart blade’ concept. Most research in this area has been on the design of cheap, reliable and effective actuators and sensors, which are necessary for economic viability of the concept. We will argue that the design of a robust feedback controller is just as critical to the success of the smart blade concept, but has been so far overlooked because of the complexities of modeling and computation involved therein.

In this paper, we take the first step in demonstrating how to build blade models with a distributed bounded uncertainty structure, in a framework appropriate for robust control analysis and design. We then discuss recent progress in distributed computationally efficient robust control techniques, scalable for very fine discretizations, and show that for coarse discretizations, even centralized techniques can be employed to design high‐performance feedback controllers for a smart blade system, with guaranteed closed loop stability and performance for a variety of operating conditions and model mismatches. Copyright © 2009 John Wiley & Sons, Ltd.
Simulating Feedback Linearization control of wind turbines using high‐order models
Authors: Kumar A. , Stol K.
Published: October 2009

As wind turbines are becoming larger, wind turbine control must now encompass load control objectives as well as power and speed control to achieve a low cost of energy. Due to the inherent non‐linearities in a wind turbine system, the use of non‐linear model‐based controllers has the potential to increase control performance. A non‐linear feedback linearization controller with an Extended Kalman Filter is successfully used to control a FAST model of the controls advanced research turbine with active blade, tower and drive‐train dynamics in above rated wind conditions. The controller exhibits reductions in low speed shaft fatigue damage equivalent loads, power regulation and speed regulation when compared to a Gain Scheduled Proportional Integral controller, designed for speed regulation alone. The feedback linearization controller shows better rotor speed regulation than a Linear Quadratic Regulator (LQR) at close to rated wind speeds, but poorer rotor speed regulation at higher wind speeds. This is due to modeling inaccuracies and the addition of unmodeled dynamics during simulation. Similar performance between the feedback linearization controller and the LQR in reducing drive‐train fatigue damage and power regulation is observed. Improvements in control performance may be achieved through increasing the accuracy of the non‐linear model used for controller design. Copyright © 2009 John Wiley & Sons, Ltd.
Solvent‐modified SiS2‐type SnS2: Synthesis, Crystal Structures and Properties of {}^1_\infty[SnS2·en] and [enH]4[Sn2S6]·en
Authors: Pada Nayek Hari , Lin Zhien , Dehnen Stefanie
Published: October 2009

Two novel Sn/S compounds, {}^1_\infty[SnS2·en] (1) and [enH]4[Sn2S6]·en (2), have been synthesized by solvothermal reactions of Cl3SnBu‐SnCl3 or tin, respectively, with elemental sulfur in ethylenediamine at 180 °C. The compound was characterized by means of X‐ray diffraction and spectroscopy. Compound 1 represents an neutral polymeric chain structure, based on [SnS2·en] units, with tin atoms in coordination number six. Thus, 1 can be viewed as SiS2‐type SnS2 in a solvated variant. Compound 2 represents a salt of the dimeric [Sn2S6]4– anion, with protonated 1,2‐diaminoethane (en) as counter cations. The structural features and properties of both compounds are discussed.
When Left Is Right: Party Ideology and Policy in Post-Communist Europe
Authors: TAVITS MARGIT , LETKI NATALIA
Published: October 2009

According to the classic partisan theory of spending, leftist parties are expected to increase government spending, and rightist parties are expected to decrease it. We argue that this relationship does not hold in post-Communist countries, where in the context of dual transition to democracy and to a market economy, leftist parties have had stronger incentives and better opportunities to enact tighter budgets, whereas rightist parties were compelled to spend more in order to alleviate economic hardships. We illustrate this theoretical argument with case studies from Hungary and Poland. We then test and find support for our theory by considering the influence of cabinet ideology on total, health, and education spending in thirteen post-Communist democracies from 1989 to 2004. We explore various alternative explanations and provide further narratives to support our causal argument.
Postcommunist ambivalence: becoming of a new formation?
Authors: Misztal Barbara A.
Published: October 2009

The initial optimistic illusions about the future of postcommunist countries have been cut short by not so encouraging developments in these societies. With the growing awareness that the postcommunist transition cannot be understood as a linear passage to a free market and parliamentary democracy, more attention is paid to the social and economic obstacles as well as to the legacy of real socialism. The feelings of increasing uncertainty about the outcome of postcommunist transformation have led some writers to characterise Eastern Europe as being in the stage of liminality (or in an inbetween stage), in which everything may happen yet little can be done (Bauman 1994: 32). Arguing from a Tocquevillian position for the need of both a strong state and a strong civil society and also adopting his insight into the importance of enlightened interest, I shall discuss factors responsible for a lack of government which operates under the rule of law, as well as discussing factors responsible for obstructing the development of civil society and the emergence of enlightened interest in the post-communist societies.
Twenty years of contrast: the French and British press during the inter-war period
Authors: Chalaby Jean K.
Published: October 2009

The purpose of this paper is to explain the causes of the contrast between the evolution of the French and British press presse franaise et britannique pendant l'entre-deux-guerres. during the inter-war period. The most visible sign of this difference was the commercial success of the British press and the stagnation of the French press. From a historical perspective, the most general factor was that market mechanism has a much more determining influence on the British rather than on the French press. While these decades were marked in Great Britain by a circulation war, competition was neutralised in France by the anti-competitive agreement reached among the leading Parisian newspapers. Market mechanisms also influenced the development of different patterns of newspaper ownership in the two nations. Stiff competition and a rational mode of newspaper ownership forced British journalists to develop journalistic practices and discursive strategies more commercially oriented than those of their French counterparts. These strategies, which constitute the primary cause of the commercial success of the British press, are illustrated by the phenomenon of depoliticisation.
Could waves mix the ocean?
Authors: FALKOVICH G.
Published: October 2009

A finite-amplitude propagating wave induces a drift in fluids. Understanding how drifts produced by many waves disperse pollutants has broad implications for geophysics and engineering. Previously, the effective diffusivity was calculated for a random set of small-amplitude surface and internal waves. Now, this is extended by Bühler & Holmes-Cerfon (J. Fluid Mech., 2009, this issue, vol. 638, pp. 5–26) to waves in a rotating shallow-water system in which the Coriolis force is accounted for, a necessary step towards oceanographic applications. It is shown that interactions of finite-amplitude waves affect particle velocity in subtle ways. An expression describing the particle diffusivity as a function of scale is derived, showing that the diffusivity can be substantially reduced by rotation.
Aspects of colibacillosis in farm animals
Authors: Wray C. , Morris J. A.
Published: October 2009

It has been known for a considerable time thatEscherichia coli, although a normal inhabitant of the intestinal tract, can also be associated with a variety of pathological conditions in man, farm animals and poultry.

When Escherich (1885) isolated from the faeces of a newborn baby an organism which is now accepted asE. coli, he considered it to be a harmless saprophyte. Laruelle (1889) was the first to suggest the possible pathogenicity of this organism, while Jensen (1893) showed that it was the cause of white scour in calves. The development of reliable serological methods facilitated the differentiation of strains and numerous workers have demonstrated an association between certain serological types ofE. coliand various disease conditions in animals. Enteric diseases in young animals are an important cause of mortality and economic loss to the farming community.
Investigation of the effectiveness of measles vaccination in children in Kenya
Authors: Bell T. M. , Tukei P. M. , Ademba G. R. , Mbugua F. M. , Gathara G. W. , Magana J. M. , Kinyanjui P. , Muli J. , Hazlett D. T. G. , Alwar J. E. A. , Kiptoon P. C. , Kireti V. N. M. , Waweru A. , Mwavuo R. , Mbogo M. , Thiongo B. , Kamande D. , Munyeti T. , Ortega J.
Published: October 2009

Laboratory studies were performed on 128 children clinically diagnosed as measles when seen at the Infectious Diseases Hospital, Kenyatta National Hospital (IDH), Nairobi (86 cases) and the Rural Health Training Centre, Maragua, Central Province (42 cases) between 9 July and 31 August 1984. A concurrent measles infection was confirmed in 95% of the children seen at IDH and in 85% of those seen at Maragua, with similar proportions of confirmations in children who had, and who had not, received measles vaccine. No differences in the number of sero-conversions nor in the absolute levels of acute or convalescent HI antibody titres could be detected between vaccinated and unvaccinated children. Analysis of the cases seen at Maragua indicates that about two thirds of the children who had received vaccine were protected. A pilot study of vaccinating children at 8 months and again at 12–13 months is suggested in an attempt to eradicate measles.
A sero-epidemiologic study of a water-borne epidemic of viral hepatitis in Kolhapur City, India
Authors: Sreenivasan M. A. , Sehgal A. , Prasad S. R. , Dhorje S.
Published: October 2009

Between February and March 1981 an epidemic of hepatitis occurred in Kolhapur City, Maharashtra State, India. Approximately 1200 cases of jaundice were reported; more than 300 patients were hospitalized and three died. The epidemiological investigations showed a distinct concentration of cases in municipal ward E of the city. Investigations of the ward E water supply system disclosed gross contamination of raw water with sewage at source. The serological studies revealed that the aetiological agent responsible for this epidemic was neither hepatitis A virus nor hepatitis B virus but was likely to have been due to a non-A, non-B hepatitis virus.
The generation time, lag time, and minimum temperature of growth of coliform organisms on meat, and the implications for codes of practice in abattoirs
Authors: Smith M. G.
Published: October 2009

The growth of coliform organisms on meat tissue from sheep carcasses processed in a commercial abattoir was investigated. The results indicated that for practical purposes the minimum temperature of growth of these organisms on meat may be taken as 8 °C. Equations were derived relating the generation time and the lag time of coliform organisms in raw blended mutton to the temperature at which the meat is held. Estimates of growth obtained with these equations were found to agree closely with the experimental results, especially at temperatures above 10 °C, and allowed the generation times and the lag times for all temperatures up to 40 °C to be calculated. These times were also found to agree closely with the times determined using a strain ofEscherichia coliinoculated into blended mutton tissue. A strain ofSalmonella typhimuriuminoculated in the same way into blended mutton tissue gave longer generation and lag times at temperatures below 15 °C. Therefore, it is believed that the calculated tables of lag and generation times included in this paper can be used to determine the length of time raw chilled meat may be held afterwards at temperatures above the minimum temperature of growth without an increase in the number of any salmonella organisms present, and these times include a safety margin at each temperature.

The study indicates that the mandatory codes of practice presently applied in commercial abattoirs are too stringent. Maintaining the temperature of boning rooms at 10 °C or less does not appear to be necessary providing the meat is processed within the calculated time limits. A relaxation of the restrictions on boning room temperatures would decrease costs, increase worker comfort and safety and would not compromise the bacteriological safety of the meat produced.
A preliminary survey of the epidemiology of bluetongue in Costa Rica and Northern Colombia
Authors: Homan E. J. , de Ruiz H. Lorbacher , Donato A. P. , Taylor W. P. , Yuill T. M.
Published: October 2009

Recent evidence of bluetongue (BT) virus infection of livestock in scattered localities in the neotropics prompted a serologic survey of cattle in Colombia and Costa Rica. In Costa Rica 48·1% of 1435 bovine animals had BT virus antibody in the agar gel precipitation test (AGPT). In Colombia 51·8% of 635 cattle were AGPT-positive for BT virus. Antibody prevalence ranged from over 50% in the lowlands to 0% in Costa Rica and 19% in Colombian cattle above 2000 m altitude. Neutralization tests indicated that Costa Rican cattle had been exposed to BT virus types 6, 12, 14 and 17.
Bluetongue virus and epizootic haemorrhagic disease of deer virus serotypes in northern Colombian cattle
Authors: Homan E. J. , Taylor W. P. , Lorbacher de Ruiz H. , Yuill T. M.
Published: October 2009

There is recent evidence of bluetongue (BT) and epizootic haemorrhagic disease (EHD) virus infection of cattle in the American tropics, including BT group reactive antibody in Colombian cattle. These observations prompted a study to determine serologically the specific BT and EHD virus types present, and time of infection and to collectCulicoidesspp. as potential vectors. A prospective study of BT and EHD virus infection was done on two farms in the Colombian department of Antioquia. Sequential sampling of young cattle indicated acquisition of neutralizing antibody to BT virus serotypes 12, 14 and 17, and EHD virus serotypes 1 and 2. Insect captures showed a high association ofCulicoides insigniswith infected cattle.
The seasonality of bacterial quality of water in a tropical developing country (Sierra Leone)
Authors: Wright R. C.
Published: October 2009

Natural water sources used as drinking-water supplies by rural settlements in Sierra Leone were examined monthly over a one-year period to detect any seasonal variations in bacterial quality. The 37 °C colony count, levels of selected faecal indicator bacteria and the incidence of Salmonella spp. were monitored. A seasonality was demonstrated for all the variables, counts generally increasing with the progression of the dry season, culminating in peaks at the transition from dry to wet season. Some complications with respect to the interpretation of counts of faecal indicator bacteria from raw tropical waters are noted.
The detection ofChlamydia trachomatisby direct immunofluorescence in conjunctival smears from patients with trachoma and patients with ophthalmia neonatorum using a conjugated monoclonal antibody
Authors: Mabey D. C. W. , Booth-Mason S.
Published: October 2009

Duplicate specimens were taken with cotton-wool swabs from the upper tarsal conjunctiva of 63 patients living in Gambian villages in which trachoma is endemic and from 34 infants with ophthalmia neonatorum (ON) attending an outpatient clinic in The Gambia. The detection ofChlamydia trachomatisby direct immunofluorescence (IF) using a conjugated monoclonal antibody to its principal outer membrane protein was compared with isolation in cycloheximide-treated McCoy cells. For trachoma, the sensitivity and specificity of the immunofluorescent technique were 62% and 100% respectively if ten elementary bodies (EBs) was taken as the minimum requirement for positivity by IF. If all cases with one or more EB were considered positive, the sensitivity was 81% and the specificity 85%. For ON the sensitivity and specificity were 100% and 95% respectively, regardless of which criterion was used. In view of its simplicity and easy applicability to field conditions it seems likely that direct IF using monoclonal antibodies may be a useful technique for the detection ofC. trachomatisin the conjunctival epithelium of patients with trachoma.
Faecal excretion of entero-pathogens in a Pakistani family returning to the U.K. after a visit to Rawalpindi
Authors: Harvey R. W. S. , Price T. H.
Published: October 2009

The family consisted of two parents and five children. While the father remained in Cardiff, the mother and all the children visited Rawalpindi, Pakistan, for 6 weeks to stay with relatives. Travel was by flight from Heathrow airport to Pakistan and by a short road journey to Rawalpindi. Mrs M. – the mother – as a guest, did no cooking on the holiday. The house which they were living in had a piped water supply, thought to be treated. There was no flush toilet but a commode was available and was emptied daily. All the children had gastro-enteritis symptoms for 2–3 days after arrival. Ru M. – a daughter – had the most severe illness and was treated by a local doctor. Diarrhoea in the three girls persisted on return to U.K. A faecal swab from Ru M. showed her to be excreting S. typhi (degraded Vi phage type). She was admitted to hospital. Faecal samples from the remaining members of the family were taken and examined for entero-pathogens. The father, Fa. M., who had not left Cardiff, had negative stools and remained free from infection. All other family members were excreting one or more enteropathogens, including a Campylobacter sp., three types of Sh. flexneri and one type of Sh. boydii. A subsequent faecal sample revealed that one of the male children, A.M., was excreting S. typhi phage type B2. The two typhoid infections were apparently unconnected.
The use of Preston enrichment broth for the isolation of ‘thermophilic’ campylobacters from water
Authors: Ribeiro C. D. , Price T. H.
Published: October 2009

The application of Preston enrichment broth to isolation of ‘thermophilic’ campylobacters from water has been investigated. Enrichment substantially increased the yield of such organisms. The optimum timing for subculturing the broth was after 48 h incubation. Despite the addition of aerotolerant supplement to the broth the number and variety of isolates was greater when the broth was incubated microaerically than when it was incubated in air.
Transferable plasmid-mediated drug resistance among non-O1 Vibrio cholerae and rough strains of Vibrio cholerae from Tamilnadu, India
Authors: Sundaram SP. , Murthy K. V.
Published: October 2009

A total of 289 non-O1 Vibrio cholerae (NVC) strains and 20 rough V. cholerae (RVC) strains isolated in an endemic area were tested for antibiotic resistance and for transferable R-plasmids. Twenty three per cent of NVC and 40% of the RVC isolates were found to be resistant to one or more drugs. Eight NVC and four RVC strains possessed multiple drug resistance, varying from four to eight drugs. The common spectrum found in NVC isolates were chloramphenicol and streptomycin (CS) or chloramphenicol, streptomycin, tetracycline and ampicillin (CSTA). Resistance to sulphamethoxazole (Su) and to trimethoprim (Tm) was encountered infrequently. In RVC isolates in addition CSTASuTm determinants, resistance markers to aminoglycosides kanamycin, gentamicin and neomycin were also found. Eighteen of the 27 V. cholerae strains with two or more resistance determinants transferred them en bloc to Escherichia coli K12. The level of resistance in the recipient strain was equal to or greater than that of the donor vibrio strains. Most of the strains possessing solitary resistance markers were unable to transfer them. βlactamase production could be demonstrated in 92·8% of the ampicillin resistant strains. None of the strains was resistant to nalidixic acid or furazolidone. The results emphasize the importance of antimicrobic susceptibility determination of V. cholerae isolates, regardless of the serotypes, before commencing chemotherapy.
An evaluation of various working practices in shops selling raw and cooked meats
Authors: Tebbutt G. M.
Published: October 2009

Three groups of premises (butchers' shops, supermarkets and general dealers) which sell raw and cooked meats were compared. Salmonellas were not detected, but Escherichia coli, and to a lesser degree Staphylococcus aureus and Streptococcus faecalis, were widely distributed in all three groups of premises. Contamination of hands, towels and nail brushes was related to poor working practices. The presence of E. coli or Str. faecalis on slicing machines was associated with contamination of meat samples. A number of wiping cloths were heavily contaminated with E. coli, and many also contained Clostridium perjringens. Few premises provided written cleaning plans, and in many cases staff did not receive an adequate training in food hygiene. The use of disinfectants as part of the cleaning process did not necessarily reduce the level of bacterial contamination. In general there was poor correlation between microbiological results and a visual inspection made by an environmental health officer. The possible reasons for this finding arc discussed.
Hepatitis B core antigen synthesised in Escherichia coli: its use for antibody screening in patients attending a clinic for sexually transmitted diseases
Authors: Cohen B. J. , Litton P. A. , Mortimer P. P. , Simmons P.
Published: October 2009

Hepatitis B core antigen (HBcAg) synthesised in Escherichia coli by recombinant DNA techniques was compared with HBcAg prepared from infected livrer tissue. The two antigens were used in radioimmunoassays (RIA) to detect antibody to HBcAg (anti-HBc) in sera from patients attending a clinic for sexually transmitted diseases. Out of 2151 sera tested, 260 were anti-HBc positive with both HBcAg preparations but seven were positive with the liver-derived antigen alone. Reasons for these discrepant results are discussed. The slight loss of sensitivity of the anti-HBc RIA using E. coli HBcAg was not considered significant when compared with the potential advantages of a synthetic antigen.

The presence of other hepatitis B markers in the 267 anti-HBc positive sera was determined: 25 contained HBsAg, 220 anti-HBs and, of the 22 that were HBsAg/anti-HBs negative, 12 contained anti-HBe. In the 10 remaining sera, anti-HBc was the only hepatitis B marker that could be found.
A search for the source ofCampylobacter jejuniin milk
Authors: Waterman Sally C. , Park R. W. A. , Bramley A. J.
Published: October 2009

Samples of milk from 1501 cows with mastitis were negative forCampylobacter jejuni. The faeces of 74 healthy Friesian cows were screened forC. jejuni: 13% of the samples were positive during the summer when the cows were on pasture, and 51% were positive in the winter when the cows were housed. Positive samples contained on average 1 × 104campylobacters per g faeces.

It is concluded that faecal contamination rather than udder infection is the means by which campylobacters enter milk and thereby infect man.
A study of F38-type and related mycoplasmas by mycoplasmaemia and cross-immunization tests in mice
Authors: Kibe M. Kanyi , Smith G. R.
Published: October 2009

In vivomethods were used to study the F38-type mycoplasma in parallel with related mycoplasmas.

Three of five strains of ‘bovine serogroup 7’ with an unknown history of subculture produced mycoplasmaemia in mice inoculated intraperitoneally. A strain of ‘bovine serogroup L’ also produced mycoplasmaemia, but no evidence of similar ability could be found for single strains ofMycoplasma capricolum, M. equigenitaliumandM. primatum, or for two strains of the F38-type mycoplasma.

In cross-immunization tests a bovine serogroup 7 strain (NCTC 10133) and a strain (‘Blenheim’) of the SC (small colony) type ofM. mycoidessubsp.mycoideswere used for the purpose of challenge. Cross-protection was described as ‘complete’ or ‘partial’, depending on whether it was as great as, or less than, that produced by homologous vaccine. Although strain NCTC 10133 protected strongly, possibly completely, against Blenheim, and Blenheim gave partial protection against NCTC 10133, challenge with NCTC 10133 and Blenheim gave strikingly different results. Thus (1) F38-type strains,M equigenitaliumandM. primatumall gave partial cross-protection against NCTC 10133 but not against Blenheim, (2) NCTC 10133, unlike Blenheim, was seldom susceptible to partial cross-protection by LC (large colony) strains ofM. mycoidessubsp.mycoides, and (3) three SC strains – which would have protected completely against Blenheim – protected only partially against NCTC 10133. NCTC 10133 and Blenheim were similar, however, in thatM. capricolumandM. mycoidessubsp.caprifailed to cross-protect against them both.