bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple melting behavior of poly(lactic acid) filled with modified carbon black
Authors: Su Zhizhong , Li Qiuying , Liu Yongjun , Hu Guo‐Hua , Wu Chifei
Published: September 2009

Two melting peaks are generally observed in a heating scan for isothermally crystallized poly(lactic acid) (PLA)/carbon black (CB) and PLA/modified carbon black (MCB) composites. To investigate the origin of the above double melting behavior, the melting behavior after isothermal crystallization was analyzed with differential scanning calorimetry, wide‐angle X‐ray diffraction, and small angel X‐ray scattering techniques. The double melting of the crystallized samples can be explained by the model of two populations of lamellae, the double peaks of low and high temperatures are contributed to the melting of the small lamellae produced by secondary crystallization and that of the major crystals formed in the primary crystallization process, respectively. Spherulitic growth rates of the neat PLA and PLA/MCB composite were analyzed and the occurrence of a regime transition was demonstrated. For the PLA, a clear regime transition was observed at around 125 °C. For the PLA/MCB, it occurred at 130 °C. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1971–1980, 2009
Enhanced photochemical‐shift of reflection band from an inverse opal film based on larger birefringent polymer liquid crystals: Effect of tolane group on the photochemical shift behavior
Authors: Moritsugu Masaki , Shirota Tomomi , Kubo Shoichi , Ogata Tomonari , Sato Osamu , Kurihara Seiji
Published: September 2009

Photo‐chemically tunable photonic band gap materials are prepared by infiltration of liquid crystal polymers having azobenzene groups into voids of SiO2 inverse opal films. Linearly polarized (LP) light irradiation results in transformation from a random to an anisotropic molecular orientation of azobenzene side chains in the voids of the SiO2 inverse opal film, leading to the reversible and stable shift of the reflection peak to longer wavelength more than 15 nm. To improve switching properties, we use copolymers of azobenzene monomer and tolane monomer, which have higher birefringence, as infiltration materials into the voids. The azobenzene‐tolane copolymers are found to show higher birefringence than azobenzene homopolymers by the LP light irradiation at higher temperature. Consequently, the reflection band of the SiO2 inverse opal film infiltrated with the azobenzene‐tolane copolymer can be shifted to longer wavelength region more than 55 nm by the irradiation of LP light. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1981–1990, 2009
Rheological properties for polypropylene modified by polytetrafluoroethylene
Authors: Md Ali Mohd Amran Bin , Okamoto Kenzo , Yamaguchi Masayuki , Kasai Toshihiro , Koshirai Atsunori
Published: September 2009

Linear and nonlinear viscoelastic properties for binary blends composed of isotactic polypropylene and polytetrafluoroethylene (PTFE) are studied. It is found that blending a small amount of PTFE greatly enhances the storage modulus in the low frequency region. Further, drawdown force and normal stress difference increase with the PTFE content. Electron microscope observation reveals that PTFE deforms into fine fibers whose diameter is smaller than 0.5 μm. The network structure composed of the fibers is responsible for the marked elastic properties. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2008–2014, 2009
High‐pressure dependence of structural evolution in polyamide 11 during annealing
Authors: Castagnet Sylvie , Thilly Ludovic
Published: September 2009

This work focuses on the pressure dependence of some microstructure changes like the secondary crystallization induced by annealing above the glass transition temperature. Polyamide 11 samples were annealed under a hydrostatic argon pressure ranging from the ambient up to 4000 bars. Structural evolutions were investigated by differential scanning calorimetry (DSC) and compared with similar experiments performed under atmospheric pressure. Pressure results in a strong shift of the endothermic peak observed in DSC traces toward lower temperatures, with a change of kinetics. The pressure sensitivity is clearly nonlinear. It decreases with increasing pressure levels until saturating above about 3000 bars. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2015–2025, 2009
The Application of Energy Dispersive Diffraction for Nondestructive Analysis of Large Material Depths and for Residual Stress Determination
Authors: Kämpfe Bernd , Luczak Falk , Urban Marco
Published: September 2009

An important advantage of energy dispersive X‐ray diffraction is the opportunity to obtain diffraction patterns without the use of a goniometer. Thus, a combination of small power X‐ray tubes, appropriate X‐ray optics and high energy resolution detectors enables the construction of small and transportable measurement devices. Specimens of different size, shape and geometry can be investigated.

Compared with conventional X‐ray diffraction, the energy dispersive method has widened the range of applications in two interesting fields. The simultaneous determination of chemical composition and crystalline structure opens possibilities for single crystal and polycrystalline material characterization.

A second effect which can be utilized successfully is based on the wide range of wavelengths, which may be integrated to create one diffraction pattern. So in contrast to the angle dispersive diffraction, a rather large range of penetration depth is available and nondestructive measurements into the depth of the specimen become possible.

In this paper, the application of X‐ray high energy dispersive diffraction is demonstrated. Examples from the fields of composites, steel and micro system technologies are presented. Residual stress analyses were preformed and the results were compared with conventional X‐ray stress analyses. New ways to evaluate high energy diffraction patterns will become necessary and some are offered here.
Co‐Crystallization and Characterization of Pharmaceutical Ingredients
Authors: Herrmann Michael , Förter‐Barth Ulrich , Kröber Hartmut , Kempa Paul Bernd , Juez‐Lorenzo Maria del Mar , Doyle Stephen
Published: September 2009

Co‐crystals may open the door to product tailoring of pharmaceutical products. Selected pharmaceutical ingredients were co‐crystallized by mechanical and supercritical methods and the products were characterized by means of X‐ray diffraction (XRD) using synchrotron radiation. The experiments revealed sub‐micron and nano‐structured composite particles, and three new phases, i.e., one cholesterol and two caffeine based. The phase separation and structure resolution of the new phases will form the aims of future investigations.
Vitamin D deficiency in young children with severe acute lower respiratory infection
Authors: McNally J. Dayre , Leis Karen , Matheson Loren A. , Karuananyake Chandima , Sankaran Koravangattu , Rosenberg Alan M.
Published: September 2009

Rationale

Acute lower respiratory infection (ALRI) is one of the most common reasons for hospitalization and intensive care unit admission among children. Season related decreases in the immunomodulatory molecule, vitamin D, remain an unexplored factor that might contribute to the increased occurrence of ALRI in children.

Objective

To investigate a possible association between vitamin D deficiency and respiratory infection by comparing serum 25 hydroxyvitamin D [25(OH)D] levels in a group of young children with ALRI to an age‐matched group without respiratory infection.

Patients and Methods

Participants with a diagnosis of bronchiolitis or pneumonia (n = 55 or 50, respectively), as well as control subjects without respiratory symptoms (n = 92), were recruited at the Royal University Hospital, Saskatoon, Saskatchewan, Canada from November 2007 to May 2008. 25(OH)D levels were measured in patient serum using a competitive enzyme linked immunoassay.

Results

The mean vitamin D level for the entire ALRI group was not significantly different from the control group (81 ± 40 vs. 83 ± 30 nmol/L, respectively). The mean vitamin D level for the ALRI subjects admitted to the pediatric intensive care unit (49 ± 24 nmol/L) was significantly lower than that observed for both control (83 ± 30 nmol/L) and ALRI subjects admitted to the general pediatrics ward (87 ± 39 nmol/L). Vitamin D deficiency remained statistically related to pediatric intensive care unit admission in the multivariate analysis.

Conclusion

No difference was observed in vitamin D levels between the entire ALRI group and control groups; however, significantly more children admitted to the pediatric intensive care unit with ALRI were vitamin D deficient. These findings suggest that the immunomodulatory properties of vitamin D might influence ALRI disease severity. Pediatr Pulmonol. 2009; 44:981–988. ©2009 Wiley‐Liss, Inc.
Types of article published in physiotherapy journals: a quantitative analysis
Authors: Paci Matteo , Cigna Claudio , Baccini Marco , Rinaldi Lucio A.
Published: September 2009

Background and Purpose. The aim of this study was to quantify and assess the types of research and review articles published in physiotherapy professional journals with international circulations. Method. Selected articles from nine physiotherapy journals in a period of five years were classified according to their study design. Results. A total number of 1627 articles were included in this study of which 205 (12.60%) were randomized controlled trial (RCT). Articles published with the highest frequency were ‘observational/descriptive studies’ (n = 305, 18.75%), whereas ‘meta‐analyses’ were the rarest ones (n = 21, 1.29%). Many articles were validation studies (n = 216, 13.28%) and articles classified as ‘others’ (n = 217, 13.34%). High heterogeneity was found in terms of distribution over years and journals with an improvement of the number of RCTs among years. Conclusion. The distribution of different types of article in physiotherapy journals is similar to other disciplines. The improvement of RCTs represents an important move in the right direction for evidence‐based physiotherapy research. Copyright © 2009 John Wiley & Sons, Ltd.
Production of functional bacteriorhodopsin by an Escherichia coli cell‐free protein synthesis system supplemented with steroid detergent and lipid
Authors: Shimono Kazumi , Goto Mie , Kikukawa Takashi , Miyauchi Seiji , Shirouzu Mikako , Kamo Naoki , Yokoyama Shigeyuki
Published: September 2009

Cell‐free expression has become a highly promising tool for the efficient production of membrane proteins. In this study, we used a dialysis‐based Escherichia coli cell‐free system for the production of a membrane protein actively integrated into liposomes. The membrane protein was the light‐driven proton pump bacteriorhodopsin, consisting of seven transmembrane α‐helices. The cell‐free expression system in the dialysis mode was supplemented with a combination of a detergent and a natural lipid, phosphatidylcholine from egg yolk, in only the reaction mixture. By examining a variety of detergents, we found that the combination of a steroid detergent (digitonin, cholate, or CHAPS) and egg phosphatidylcholine yielded a large amount (0.3–0.7 mg/mL reaction mixture) of the fully functional bacteriorhodopsin. We also analyzed the process of functional expression in our system. The synthesized polypeptide was well protected from aggregation by the detergent‐lipid mixed micelles and/or lipid disks, and was integrated into liposomes upon detergent removal by dialysis. This approach might be useful for the high yield production of functional membrane proteins.
Fate of vinclozolin, thiabendazole and dimethomorph during storage, handling and forcing of chicory
Authors: Spanoghe Pieter , Ryckaert Bert , Van Gheluwe Cindy , Van Labeke Marie‐Christine
Published: September 2009

BACKGROUND: As part of ongoing research for a sustainable production of Belgian endives, the fate of three fungicides during storage, handling and forcing of witloof chicory roots was investigated. Storage roots are protected against Sclerotinia sp. Fuckel and Phoma exigua var. exigua Desm. by means of vinclozolin and thiabendazole respectively. During hydroponic forcing, the most imminent pathogen is Phytophthora cryptogea Pethybr. & Laff., which is controlled by the use of dimethomorph.

RESULTS: Vinclozolin and thiabendazole concentrations on roots remained constant during storage at −1 °C. Dermal exposure of the workers in hydroponics was exceeded. Vinclozolin and thiabendazole residues were not detected 2 weeks after hydroponic forcing; dimethomorph was still detected at harvest. At harvest, the vinclozolin concentration in the chicory heads was below the maximum residue limit, but the chicory roots contained residues much above the thiabendazole and dimethomorph maximum residue level.

CONCLUSION: Vinclozolin and thiabendazole residues applied before storage are still present on the roots at the start of the forcing cycle. During the set‐up of chicory roots, preventive measures are recommended, as effects of repeated human exposure to low doses of applied fungicides cannot be excluded. Dimethomorph applied at the start of the hydroponic forcing is the only pesticide detected in the drainage water at harvest. The chicory heads were safe for human consumption. However, more attention should be paid to the residues of fungicides in the roots used for cattle feeding. Copyright © 2009 Society of Chemical Industry
Schweißnahtnachbehandlung mit höherfrequenten Hämmerverfahren – Ermüdungsfestigkeit, Qualitätssicherung, Bemessung
Authors: Ummenhofer Thomas , Herion Stefan , Weich Imke
Published: September 2009

Im Rahmen des Forschungsprojekts REFRESH wurden umfangreiche systematische Untersuchungen zur Ermüdungsfestigkeit mit höherfrequenten Hämmerverfahren nachbehandelter Schweißnähte durchgeführt. Die statistisch abgesicherten Ergebnisse belegen die hohe ermüdungsfestigkeitssteigernde Wirksamkeit der Verfahren und ermöglichten die Entwicklung eines experimentell abgesicherten Bemessungskonzeptes. Um die Anwendung überwachen zu können und die Behandlungsqualität sicherzustellen, wurde ein Qualitätssicherungssystem und ein Anforderungskatalog an das Fachpersonal erarbeitet. Die Zertifizierung der Verfahren erfolgt auf Basis eines gemeinsam von der Bundesanstalt für Materialforschung und ‐prüfung und der Versuchsanstalt für Stahl, Holz und Steine der Universität Karlsruhe erarbeiteten Zertifizierungssystems.

Postweld treatment by high frequency hammer peening methods – fatigue resistance, quality control, design.

In the range of the research project REFRESH comprehensive, systematic investigations regarding the fatigue resistance of welds treated with high frequency peening methods have been conducted. The statistically confirmed results prove the high beneficial effect of the methods and allowed to develop an experimentally verified design concept. In order to control the application quality and to ensure the desired effects a quality assurance system and a catalogue of requirements for specialists has been worked out. The certification of the methods is performed on the base of a common certification system, developed by the German Federal Institute for Material Research and Testing (BAM) and the Research Centre for Steel, Timber and Masonry, University of Karlsruhe.
Messverfahren zur Überprüfung randschichtnaher Veränderungen des Werkstoffzustandes als Folge mechanischer Oberflächenbehandlungen
Authors: Eslami‐Chalandar Hamdollah , Bruns Markus , Nitschke‐Pagel Thomas , Dilger Klaus
Published: September 2009

Zur Charakterisierung der ermüdungsrelevanten Werkstoffveränderungen infolge hochfrequenter Schweißnahtnachbehandlung hat sich der Einsatz von mikromagnetischen Werkstoff‐ und Spannungsanalysen vorteilhaft gezeigt. Für Standardbauteile hat sich gezeigt, dass die Qualitätssicherung der Nachbehandlung mit höherfrequenten Hämmerverfahren bei Einhaltung der Behandlungsparameter durch eine Sichtkontrolle möglich ist. Das Mikromagnetische Verfahren ermöglicht bei neuen Anwendungsfällen eine Gütekontrolle der Nachbehandlung an Arbeitsproben ·und am Realbauteil.

A measurement technique for inspection of material subsurface changes after mechanical surface treatment.

The micro‐magnetic stress and material analysis has shown to be advantageous for characterizing the fatigue related material properties after high frequency post weld treatment. The quality control of standard parts treated by high frequency hammer peeing with the same peening parameters is possible by means of visual inspection. For new applications, the micro‐magnetic analysis provides a quality control of post weld treated work samples and real components.
Alternativer Berechnungsansatz zum Hochfrequenzhämmern – Versuch und praktische Anwendung in der Windenergietechnik
Authors: Rahlf Uwe
Published: September 2009

Die lokal anwendbare Schweißnahtnachbehandlung bietet ein vielversprechendes Potential zur Lebensdauerverlängerung und wirtschaftlicheren Fertigung geschweißter Bauteile. In diesem Beitrag wird ein alternativer Berechnungsansatz auf bruchmechanischer Basis vorgestellt, der es erlaubt, wesentliche Effekte des Hochfrequenzhämmerns, die für die signifikante Verlängerung der Lebensdauer verantwortlich zeichnen, direkt in die Abschätzung der Lebensdauer mit einfließen zu lassen. Ferner werden die Ergebnisse eines Schwingfestigkeitsversuches an dickwandigen, durchgeschweißten Kreuzstößen mit einer Blechdicke von 60 mm präsentiert.

Auch aufgrund der sehr positiven Erfahrungen aus der Anwendung des Hochfrequenzhämmerns an verschiedenen Bauteilen von Windenergieanlagen in der Praxis wird diesem Verfahren zukünftig eine hohe Bedeutung zukommen.

An alternative calculation approach for high frequency peening – further validation and practical application in wind energy technology.

A local application of post weld treatment shows a high potential in increasing fatigue life and more economic manufacturing of welded components. An alternative assessment based on fracture mechanics is presented which takes into account the main effects of high frequency peening. Furthermore results of a fatigue test on a cross‐joint K‐butt weld with 60?mm thickness are presented. Also because of positive experiences in field application of high frequency peening on different components in wind energy converters this kind of post weld treatment will be a very promising technique in future.
Personenaufzug Bad Schandau – Revitalisierung eines denkmalgeschützten Turmbauwerks
Authors: Stroetmann Richard , Flederer Holger , Schmidt Holger , Sieber Lars
Published: September 2009

Die im Jahr 1904 errichtete und unter Denkmalschutz stehende Personenaufzugsanlage in Bad Schandau gehört zu den wichtigsten touristischen Attraktionen der Stadt. Sie verbindet das Elbtal mit der Ostrauer Scheibe. Das Tragwerk der Stahlskelettkonstruktion besteht aus einem 57 m hohen Aufzugsturm und einer 27 m langen bergseitigen Zugangsbrücke mit einer Λ‐förmigen Zwischenstütze. Wegen starker Korrosionsschäden wurde im vergangenen Jahr die Grundinstandsetzung der Anlage durchgeführt. Der folgende Beitrag geht nach einem geschichtlichen Rückblick und der Konstruktionsbeschreibung auf die durchgeführten Zustands‐ und Materialanalysen ein und beschreibt die Planung und Ausführung der Revitalisierungsmaßnahmen.

Passenger lift Bad Schandau – Revitalization of a tower structure under preservation order.

The passenger lift, one of the most important tourist attractions in Bad Schandau, was built in 1904 and is placed under preservation order. It joins the Elbe valley with the uptown district “Ostrauer Scheibe”. The steel framework structure consists of a 57 m high lift tower and a 27 m long entrance bridge facing the mountain and having a Λ ‐shaped intermediate support. Last year major repair works were carried out due to enormous corrosion damages of the structure. Following a historical review and design description this paper presents building condition and material evaluation as well as planning and implementation of revitalisation measures.
Real‐time fetal magnetic resonance imaging for the dynamic visualization of the pouch in esophageal atresia
Authors: Salomon L. J. , Sonigo P. , Ou P. , Ville Y. , Brunelle F.
Published: September 2009

Esophageal atresia is the principal cause of congenital esophageal obstruction. Prenatal suspicion of esophageal atresia is usually based on the presence of polyhydramnios together with an absent stomach bubble. More recently, visualization of the dilatation of the blind‐ending esophagus (esophageal pouch) during fetal swallowing has been reported and proposed as the most reliable sign for predicting esophageal atresia. Improvement of radiofrequency and computer technology as well as parallel data acquisition has greatly reduced magnetic resonance (MR) scanning time, allowing visualization of the fetus in cine‐mode using fast imaging employing steady‐state acquisition (FIESTA). We describe the application of FIESTA sequences in fetuses with suspected esophageal atresia for visualization of the esophageal pouch using MR imaging. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
The Gastric Band: First‐Choice Procedure for Obesity Surgery
Authors: Favretti Franco , Ashton David , Busetto Luca , Segato Gianni , De Luca Maurizio
Published: September 2009

The advent of laparoscopic adjustable gastric banding (LAGB) during the latter part of the 20th century represents a watershed in the management of chronic obesity. In this paper we provide an overview of LAGB with respect to its development, clinical outcomes, and future role. We also address current controversies, including a comparison of LAGB with Roux‐en‐Y gastric bypass (RYGBP). At present LAGB seems to be increasing in popularity in the United States, whereas in Europe there seems to be a trend away from gastric banding toward RYGBP. Optimal outcomes after LAGB are a function of correct laparoscopic technique, an experienced surgical team, a well‐engineered device, and intensive long‐term follow‐up. The majority of studies show that LAGB is an extremely safe and effective procedure, with an operative mortality of 0–0.1% and excess weight loss (%EWL) of 50–60%. Commensurate with this degree of weight loss, almost all studies show substantial improvements in obesity‐related co‐morbidities, such as hypertension, type II diabetes, and dyslipidemia. In addition, LAGB has been shown to be both safe and effective in the super‐obese, in adolescents, and in older patients and can be delivered as an ambulatory procedure. Operative mortality and early complication rates are significantly higher for RYGBP and, whilst gastric bypass results in greater weight loss than LAGB in the first 2 years, at 3 years and beyond the difference appears to be less marked. Overall, LAGB provides a safe, effective intervention for obese patients and remains our first‐choice procedure for bariatric surgery.
An off-line map-matching algorithm for incomplete map databases
Authors: Pereira Francisco Câmara , Costa Hugo , Pereira Nuno Martinho
Published: September 2009

The task of map-matching consists of finding a correspondence between a geographical point or sequence of points (e.g. obtained from GPS) and a given map. Due to many reasons, namely the noisy input data and incomplete or inaccurate maps, such a task is not trivial and can affect the validity of applications that depend on it. This includes any Transport Research projects that rely on post-hoc analysis of traces (e.g. via Floating Car Data). In this article, we describe an off-line map-matching algorithm that allows us to handle incomplete map databases. We test and compare this with other approaches and ultimately provide guidelines for use within other applications. This project is provided as open source.
Silencing of calpain expression reduces the metastatic potential of human osteosarcoma cells
Authors: Fan De‐Gang , Dai Jing‐Yao , Tang Juan , Wu Ming‐Mei , Sun Si‐Guo , Jiang Jian‐Li , Fan Qing‐Yu
Published: September 2009

Osteosarcoma, the most common primary bone tumor in young adults, is characterized by local invasion and distant metastasis. But detailed mechanisms of tumorigenicity and metastasis of osteosarcoma are not well known. We report the involvement of calpains, a family of calcium‐activated, cysteine proteases, in the invasive and metastatic processes of human osteosarcoma cells. By using siRNA treatment, the expression of μ‐ and m‐calpains were downregulated in human Saos‐2 osteosarcoma cells. Both the adhesive and invasive potentials were significantly attenuated in calpain siRNA‐transfected human Saos‐2 osteosarcoma cells. MMPs are the main factors involved in malignant tumor invasion and metastasis. siRNA of calpains also significantly inhibited the secretion of MMP‐2 in Saos‐2 cells. These results suggest that μ‐ and m‐calpains are important in the invasion and metastasis of human osteosarcoma cells, and calpains might be targeted to reduce tumor progression.
Ensuring patient satisfaction with second‐trimester abortion in resource‐poor settings
Authors: Regmi Kiran , Madison Jeanne
Published: September 2009

Objective

To evaluate patient satisfaction with the new second‐trimester abortion services in Nepal.

Method

Depending on the patient's literacy level, a questionnaire was read and filled out by the patient herself or by an interviewer. Indicators were developed and assessed to determine the patient's experience of the services, focusing on her physical, emotional, and social comfort.

Results

Satisfaction was found to be high for characteristics associated with counseling and the caring attitude of the physician. However, dissatisfaction was expressed regarding some aspects of the delivery of care, especially the lack of privacy and confidentiality and the absence of a support person from the patient's own family.

Conclusion

The patients described privacy, confidentiality, and a support person designated by them as factors that would greatly contribute to their satisfaction with the services. Maximizing patient satisfaction is necessary for the program's success but will be challenging.
The effect of sudden source buoyancy flux increases on turbulent plumes
Authors: SCASE M. M. , ASPDEN A. J. , CAULFIELD C. P.
Published: September 2009

Building upon the recent experimentally verified modelling of turbulent plumes which are subject to decreases in their source strength (Scase et al., J. Fluid Mech., vol. 563, 2006b, p. 443), we consider the complementary case where the plume's source strength is increased. We consider the effect of increasing the source strength of an established plume and we also compare time-dependent plume model predictions for the behaviour of a starting plume to those of Turner (J. Fluid Mech., vol. 13, 1962, p. 356).

Unlike the decreasing source strength problems considered previously, the relevant solution to the time-dependent plume equations is not a simple similarity solution. However, scaling laws are demonstrated which are shown to be applicable across a large number of orders of magnitude of source strength increase. It is shown that an established plume that is subjected to an increase in its source strength supports a self-similar ‘pulse’ structure propagating upwards. For a point source plume, in pure plume balance, subjected to an increase in the source buoyancy flux F0, the rise height of this pulse in terms of time t scales as t3/4 while the vertical extent of the pulse scales as t1/4. The volume of the pulse is shown to scale as t9/4. For plumes in pure plume balance that emanate from a distributed source it is shown that the same scaling laws apply far from the source, demonstrating an analogous convergence to pure plume balance as that which is well known in steady plumes. These scaling law predictions are compared to implicit large eddy simulations of the buoyancy increase problem and are shown to be in good agreement.

We also compare the predictions of the time-dependent model to a starting plume in the limit where the source buoyancy flux is discontinuously increased from zero. The conventional model for a starting plume is well approximated by a rising turbulent, entraining, buoyant vortex ring which is fed from below by a ‘steady’ plume. However, the time-dependent plume equations have been defined for top-hat profiles assuming only horizontal entrainment. Therefore, this system cannot model either the internal dynamics of the starting plume's head or the extra entrainment of ambient fluid into the head due to the turbulent boundary of the vortex ring-like cap. We show that the lack of entrainment of ambient fluid through the head of the starting plume means that the time-dependent plume equations overestimate the rise height of a starting plume with time. However, by modifying the entrainment coefficient appropriately, we see that realistic predictions consistent with experiment can be attained.
Numerical simulation of Faraday waves
Authors: PÉRINET NICOLAS , JURIC DAMIR , TUCKERMAN LAURETTE S.
Published: September 2009

We simulate numerically the full dynamics of Faraday waves in three dimensions for two incompressible and immiscible viscous fluids. The Navier–Stokes equations are solved using a finite-difference projection method coupled with a front-tracking method for the interface between the two fluids. The critical accelerations and wavenumbers, as well as the temporal behaviour at onset are compared with the results of the linear Floquet analysis of Kumar & Tuckerman (J. Fluid Mech., vol. 279, 1994, p. 49). The finite-amplitude results are compared with the experiments of Kityk et al (Phys. Rev. E, vol. 72, 2005, p. 036209). In particular, we reproduce the detailed spatio-temporal spectrum of both square and hexagonal patterns within experimental uncertainty. We present the first calculations of a three-dimensional velocity field arising from the Faraday instability for a hexagonal pattern as it varies over its oscillation period.
Intrusive gravity currents from finite-length locks in a uniformly stratified fluid
Authors: MUNROE J. R. , VOEGELI C. , SUTHERLAND B. R. , BIRMAN V. , MEIBURG E. H.
Published: September 2009

Gravity currents intruding into a uniformly stratified ambient are examined in a series of finite-volume full-depth lock-release laboratory experiments and in numerical simulations. Previous studies have focused on gravity currents which are denser than fluid at the bottom of the ambient or on symmetric cases in which the intrusion is the average of the ambient density. Here, we vary the density of the intrusion between these two extremes. After an initial adjustment, the intrusions and the internal waves they generate travel at a constant speed. For small departures from symmetry, the intrusion speed depends weakly upon density relative to the ambient fluid density. However, the internal wave speed approximately doubles as the waves change from having a mode-2 structure when generated by symmetric intrusions to having a mode-1 structure when generated by intrusions propagating near the bottom. In the latter circumstance, the interactions between the intrusion and internal waves reflected from the lock-end of the tank are sufficiently strong and so the intrusion stops propagating before reaching the end of the tank. These observations are corroborated by the analysis of two-dimensional numerical simulations of the experimental conditions. These reveal a significant transfer of available potential energy to the ambient in asymmetric circumstances.
Turbulence structure in a boundary layer with two-dimensional roughness
Authors: VOLINO R. J. , SCHULTZ M. P. , FLACK K. A.
Published: September 2009

Turbulence measurements for a zero pressure gradient boundary layer over a two-dimensional roughness are presented and compared to previous results for a smooth wall and a three-dimensional roughness (Volino, Schultz & Flack,J. Fluid Mech., vol. 592, 2007, p. 263). The present experiments were made on transverse square bars in the fully rough flow regime. The turbulence structure was documented through the fluctuating velocity components, two-point correlations of the fluctuating velocity and swirl strength and linear stochastic estimation conditioned on the swirl and Reynolds shear stress. The two-dimensional bars lead to significant changes in the turbulence in the outer flow. Reynolds stresses, particularly$\overline {{v'}^2} ^ +$and$ - \overline {{u}'{v}'} ^ + $, increase, although the mean flow is not as significantly affected. Large-scale turbulent motions originating at the wall lead to increased spatial scales in the outer flow. The dominant feature of the outer flow, however, remains hairpin vortex packets which have similar inclination angles for all wall conditions. The differences between boundary layers over two-dimensional and three-dimensional roughness are attributable to the scales of the motion induced by each type of roughness. This study has shown three-dimensional roughness produces turbulence scales of the order of the roughness heightkwhile the motions generated by two-dimensional roughness may be much larger due to the width of the roughness elements. It is also noted that there are fundamental differences in the response of internal and external flows to strong wall perturbations, with internal flows being less sensitive to roughness effects.
Pumping or drag reduction?
Authors: HŒPFFNER JÉRÔME , FUKAGATA KOJI
Published: September 2009

Two types of wall actuation in channel flow are considered: travelling waves of wall deformation (peristalsis) and travelling waves of blowing and suction. The flow response and its mechanisms are analysed using nonlinear and weakly nonlinear computations. We show that both actuations induce a flux in the channel in the absence of an imposed pressure gradient and can thus be characterized as pumping. In the context of flow control, pumping and drag reduction are strongly connected, and we seek to define them properly based on these two actuation examples. Movies showing the flow motion for the two types of actuation are available with the online version of this paper (journals.cambridge.org/FLM).
Shallow-water analysis of gravity-current flows past isolated obstacles
Authors: GONZALEZ-JUEZ E. , MEIBURG E.
Published: September 2009

The flow of a partial-depth lock-exchange gravity current past an isolated bottom-mounted obstacle is studied by means of two-dimensional direct numerical simulations and steady shallow-water theory. The simulations indicate that the flux of the current downstream of the obstacle is approximately constant in space and time. This information is employed to extend the shallow-water models of Rottman et al. (J. Hazard. Mater., vol. 11, 1985, pp. 325–340) and Lane-Serff, Beal & Hadfield (J. Fluid Mech., vol. 292, 1995, pp. 39–53), in order to predict the height and front speed of the downstream current as functions of the upstream Froude number and the ratio of obstacle to current height. The model predictions are found to agree closely with the simulation results. In addition, the shallow-water model provides an estimate for the maximum drag that lies within 10% of the simulation results for obstacles much larger than the boundary-layer thickness.
Recurrent laryngeal nerve paralysis due to subclinical Lyme borreliosis
Authors: Karosi T , Rácz T , Szekanecz É , Tóth Á , Sziklai I
Published: September 2009

Objective:

We report an extremely rare case of recurrent laryngeal nerve paralysis due to subclinical Lyme borreliosis.

Method:

Case report presenting a 15-year-old girl referred with hoarseness and soft voice.

Results:

Right-sided recurrent laryngeal nerve paralysis was observed using videolaryngoscopy. Imaging was used to exclude intracranial, cervical and intrathoracic embryological lesions, vascular malformations and tumours. Laboratory and electrophysiological investigations were used to exclude inflammatory and paraneoplastic processes, endocrinopathy and metabolic disorders. Serological testing was positive for Lyme disease. Parenteral ceftriaxone therapy was commenced. The patient's nerve paralysis showed complete recovery on the seventh day of antibiotic treatment; this was confirmed by videolaryngoscopy.

Conclusion:

Recurrent laryngeal nerve paralysis is an extremely rare complication of neuroborreliosis associated with Lyme disease. In patients with recurrent laryngeal nerve paralysis in whom the clinical history is uncertain and the usual diagnostic methods give negative results, screening with anti-borrelia immunoglobulin M is suggested.
Vocal fold paralysis: role of bilateral transverse cordotomy
Authors: Bajaj Y , Sethi N , Shayah A , Harris A T , Henshaw P , Coatesworth A P , Nicolaides A R
Published: September 2009

Objective:

Although modern endoscopic laser techniques aim to avoid a permanent tracheostomy by augmenting the glottic aperture in cases of bilateral vocal fold palsy, loss of tissue from the posterior glottis risks compromising voice quality and swallowing function. The objective of this study was to describe our experience with bilateral transverse posterior cordotomy.

Methods:

This was a retrospective analysis of functional outcomes in a series of consecutive patients undergoing a simple modification of the classical laser cordectomy procedure, which avoids tissue loss. The procedure was confined to the complete release of the vocal ligament from the arytenoid cartilage on both sides, while avoiding any significant loss of mucosa or cartilage.

Results:

Post-operative voice quality and quality of life were rated as good by most patients, which makes bilateral transverse cordotomy an attractive treatment option for bilateral vocal fold paralysis.

Conclusion:

Bilateral transverse cordotomy is a reliable treatment option for patients with bilateral vocal fold paralysis, and aims to avoid the morbidity associated with a permanent tracheostomy.
The Chinese Amigo: Implications for the Development of Equatorial Guinea
Authors: Esteban Mario
Published: September 2009

In the last five years China has dramatically increased its presence in Africa. Despite its abundant natural resources, the notoriety of its political regime and its close relationship with Beijing, Equatorial Guinea is a glaring omission in the China–Africa literature. This article intends to fulfil that gap by analysing the bilateral relationship between Beijing and Malabo at both the official and the social levels to assess its impact on the development of Equatorial Guinea. As bad governance is the main obstacle for the development of Equatorial Guinea, the article compares the role played by Chinese companies and government in reinforcing Obiang's authoritarian regime with that played by their Western counterparts. It concludes that Chinese extractive firms play a marginal role in the financial extraversion that strongly links the Obiang regimen with US oil companies. Conversely, the Chinese government offers Obiang more extensive and stable support than Western governments to the extent that most of the undeniable developmental potential of Chinese co-operation is wasted through clientelist networks.
Chinese Shops and the Formation of a Chinese Expatriate Community in Namibia
Authors: Dobler Gregor
Published: September 2009

The first Chinese migrants came to the Namibian border boom town Oshikango in 1999. Today, there are over 100 shops which sell Chinese goods to Angolan traders in that town of only around 10,000 inhabitants. This article describes their way of doing business and the economic interactions between migrants and the host society. By reacting to the host society's reaction to them, Chinese shopkeepers in Namibia are gradually developing into a migrant society with a distinct social structure. In an increasingly hostile political climate, Chinese entrepreneurs are faced with stronger regulation. This has not had the intended effect of pushing shopkeepers into manufacturing. Instead, it has sharpened social stratification among migrants, with traders better connected to Namibian authorities using their connections as an additional resource. In an optimistic view, the alliance between successful Chinese and Namibian actors could be the germ for a spill-over of Chinese entrepreneurial success; in a pessimistic view, it will create additional rents for some Namibians and give migrants the leverage to evade regulations.
African Perspectives on China–Africa Links
Authors: Sautman Barry , Hairong Yan
Published: September 2009

Scholars and the international media often allude to a putative “African view” of Africa–China links, constructed from anecdotal evidence. Using random sample and university-based surveys, we elaborate the first empirically based study of what Africans think of their relationships with China. We reach three conclusions. First, African views are not nearly as negative as Western media make out, but are variegated and complex. Second, the survey results are at variance with the dominant Western media representation that only African ruling elites are positive about these links. Third, we find that the dominant variation in African perspectives is by country, compared with variations such as age, education and gender. The differences among countries in attitudes towards China are primarily a function of the extent to which national politicians have elected to raise the “Chinese problem” and, secondarily, the extent of Western media influence in African states.
Representations of Africa in a Hong Kong Soap Opera: The Limits of Enlightened Humanitarianism inThe Last Breakthrough
Authors: Saavedra Martha
Published: September 2009

Several studies have looked at “Africa” in the Western imagery, and explored how it is constructed for Americans through popular media. This article offers a preliminary query into whether Chinese popular media functions in a similar way by examining a 2004 Hong Kong-produced soap opera that uses a medical humanitarian mission in Kenya to advance its plot and central themes. While many tropes regarding Africa found in Western media are repeated, there is a conscious effort in this production to embody a more enlightened approach. Nevertheless, the core relationship is marked by humanitarianism, and necessarily one embodying unequal power relations. The soap opera thus avoids critical questions of development, globalization or even post-colonial solidarity, and instead rests more on older, safer paradigms of modernization. Still, an analysis of the drama reveals contradictions and unresolved tensions in which the relationship with Africa parallels Hong Kong's relationship with mainland China. This study posits that popular culture can offer unique insights into understanding dynamics affecting the evolving relationship between China and Africa.
The Past in the Present: Historical and Rhetorical Lineages in China's Relations with Africa
Authors: Strauss Julia C.
Published: September 2009

China's official rhetoric on its relations with Africa is important; it frames, legitimates and renders comprehensible its foreign policy in this ever-important area of the world. This article explores the following puzzle: why China's rhetoric on its involvement with Africa has retained substantial continuities with the Maoist past, when virtually every other aspect of Maoism has been officially repudiated. Despite the burgeoning layers of complexity in China's increasing involvement in Africa, a set of surprisingly long-lived principles of non-interference, mutuality, friendship, non-conditional aid and analogous suffering at the hands of imperialism from the early 1960s to the present continue to be propagated. Newer notions of complementarity and international division of labour are beginning to come in, but the older rhetoric still dominates official discourse, at least in part because it continues to appeal to domestic Chinese audiences.
Women, Enclosure and Estate Improvement in Eighteenth-Century Northamptonshire
Authors: McDONAGH BRIONY A. K.
Published: September 2009

This paper examines the role of elite women in estate management, enclosure and landscape improvement in eighteenth-century England, a topic which has to date received little in the way of sustained academic consideration. The paper focuses on four women who took control of sizeable Northamptonshire estates in the 1760s and early 1770s, and demonstrates that these women were active as both managers and innovators. In examining the women's involvement in estate management, the paper explores a series of important questions about women's place in the history of parliamentary enclosure and landscape improvement, as well as women's role in eighteenth-century society more generally.
The Rise and Decline of Village Reading Rooms
Authors: KING CAROLE
Published: September 2009

This article describes the development of the reading room, from the mid-nineteenth to the mid-twentieth century. Reading rooms were originally imposed upon the working classes by the upper classes, mainly the church and local landowners. Their establishment reflected contemporary attitudes to philanthropy, recreation and self-help and confirmed the great class divide. Little research has been carried out on this subject, and this article focuses particularly on rural Norfolk, explaining the distribution of the one hundred and sixty village reading rooms identified, their varying location and architectural styles, membership profile and differing methods of financing, including fund-raising social events. The article uses local and national archives and contemporary Ordnance Survey maps, as well as information from many local people. Reading rooms offered a much needed alternative to the public house for the working classes, although they tended to appeal more to the lower middle classes, and membership was mostly restricted to males. The difference between reading rooms in ‘open’ and ‘closed’ parishes is discussed. In the twentieth century, as other diversions appeared and the countryside became more democratised, reading rooms gradually declined. They were an important part of village life and have left interesting evidence of former lifestyles and attitudes.
A lexicon of contratenor behaviour: case studies of equal-cantus Italian motets from the MS Bologna Q.15
Authors: WESTERHAUS ANDREW
Published: September 2009

This paper considers contratenor parts in equal-cantus Italian motets found in the manuscript Bologna Q.15 from codicological, contrapuntal and stylistic perspectives. After establishing criteria for contratenor classification, the paper collates a lexicon of rules governing contratenor behaviour in fourteen motets by Johannes Carmen, Johannes Ciconia, Christoforus de Monte, Antonius Romanus, Matheus de Brixia, and Antonius de Civitate. Four paradigmatic motets are presented as case studies. Q.15 is the earliest (or only extant) source for many of these contratenors, several of which were probably added by a later composer, and they exhibit remarkably similar behaviour that we might term a ‘Q.15 style’. Finally, the lexicon is employed to distinguish between the features of an original contratenor and a later one, and the paper posits that studying contratenors can offer a unique window into fifteenth-century compositional thinking.
The ‘restoration’ of plainchant in the Premonstratensian Order
Authors: HOONDERT MARTIN J.M.
Published: September 2009

In 1910 the Premonstratensian Order acquired its own Graduale. Soon after the publication of this Graduale doubts were expressed about its authenticity. Still, to this very day the Premonstratensians stand by their ‘own’ chant and use the 1910 Graduale. In this article, I reveal that the Graduale is not a reconstruction of Premonstratensian chant of the twelfth or thirteenth centuries and I also attempt to explain why the Premonstratensians undertook the quest for their ‘own authentic’ Premonstratensian chant.