bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients' preference for subsequent therapy following secondary failure of metformin and sulphonylurea
Authors: Khan H , Coyle FM , Chowdhury TA
Published: September 2009

We surveyed 205 type 2 diabetic patients with glycated haemoglobin 7.5‐10.0% on maximum metformin and sulphonylurea to determine their choice for further glycaemic therapy. In all, 54.6% of patients requested pioglitazone, 21.9% basal insulin, and 23.4% preferred exenatide. South Asians generally preferred non‐injectables, and more overweight patients preferred exenatide.

Despite physician preference for insulin, most patients prefer additional oral agents over injectables. Copyright © 2009 John Wiley & Sons, Ltd.
Thermo‐ and pH‐sensitive poly(vinylmethyl ether)/carboxymethylchitosan hydrogels crosslinked using electron beam irradiation or using glutaraldehyde as a crosslinker
Authors: Yan Shifeng , Yin Jingbo , Yu Yang , Luo Kun , Chen Xuesi
Published: September 2009

BACKGROUND: Stimuli‐sensitive or intelligent hydrogels have been investigated for many biomedical and pharmaceutical applications. Those hydrogels with dual sensitivity will have more extensive potential applications. The aim of the work presented was to prepare a series of thermo‐ and pH‐sensitive hydrogels based on poly(vinylmethyl ether) (PVME) and carboxymethylchitosan (CMCS). The hydrogels were crosslinked using electron beam irradiation (EB) or using glutaraldehyde (GA) as a crosslinker at room temperature.

RESULTS: The structures of the PVME/CMCS hydrogels obtained using the two crosslinking methods are proposed. The effects of component polymer ratio, GA content, irradiation dose, temperature and pH on the swelling behavior of the PVME/CMCS hydrogels were studied. There is a sharp decrease in the swelling ratios when the temperature increases from 25 to 37 °C. At low pH and also at high pH, the hydrogels have a higher swelling ratio; however, deswelling occurs evidently at a pH of around 3.

CONCLUSION: The study shows that both EB and GA crosslinked hydrogels are thermo‐ and pH‐ sensitive, simultaneously. Thus, they may be potential candidates for both thermo‐ and pH‐sensitive applications. Copyright © 2009 Society of Chemical Industry
Charge storage of ternary polymer blends based on poly(phenylene ether)
Authors: Lovera Deliani , Ruckdäschel Holger , Altstädt Volker , Schmidt Hans‐Werner
Published: September 2009

BACKGROUND: Charge storage capability is a fundamental property of polymers used in electromechanical transducer applications. In this work, the charge retention of ternary blends of poly(phenylene ether) and polystyrene modified with poly(styrene‐co‐acrylonitrile), polystyrene‐block‐poly(ethylene‐co‐butylene)‐block‐polystyrene or polystyrene‐block‐polyisobutylene‐block‐polystyrene (SIBS) triblock copolymers was correlated with the blend composition, final morphology and the chemical structure of the components.

RESULTS: It was determined that the charge storage capability is favoured by a finely dispersed and non‐interconnected phase and can be reduced by high polarity or low molecular weight of the blend components. Additionally, the molecular weight and the amount of styrene of the copolymers also determined the phase morphology, which in turn affected the charge retention. The use of SIBS for the ternary blends, especially in small quantities, significantly improved the charge storage. As such, 100 µm films with a surface potential of about 400 V were able to retain up to 240 V (60%) after 24 h at 130 °C.

CONCLUSION: The electret behaviour of the polymer blends was influenced by a complex relationship between chemical structure, molecular weight and phase morphology. Copyright © 2009 Society of Chemical Industry
Synthesis of rosin‐based flexible anhydride‐type curing agents and properties of the cured epoxy
Authors: Wang Honghua , Liu Xiaoqing , Liu Bo , Zhang Jinwen , Xian Ming
Published: September 2009

BACKGROUND: Although rosin acid derivatives have received attention in polymer synthesis in recent years, to the best of our knowledge, they have rarely been employed as epoxy curing agents. The objective of the study reported here was to synthesize rosin‐based flexible anhydride‐type curing agents and demonstrate that the flexibility of a cured epoxy resin can be manipulated by selection of rosin‐based anhydride‐type curing agents with appropriate molecular rigidity/flexibility.

RESULTS: Maleopimarate‐terminated low molecular weight polycaprolactones (PCLs) were synthesized and studied as anhydride‐type curing agents for epoxy curing. The chemical structures of the products were confirmed using 1H NMR spectroscopy and Fourier transform infrared spectroscopy. Mechanical and thermal properties of the cured epoxy resins were studied. The results indicate that both the epoxy/anhydride equivalent ratio and the molecular weight of PCL diol play important roles in the properties of cured resins.

CONCLUSION: Rosin‐based anhydride‐terminated polyesters could be used as bio‐based epoxy curing agents. A broad spectrum of mechanical and thermal properties of the cured epoxy resins can be obtained by varying the molecular length of the polyester segment and the epoxy/curing agent ratio. Copyright © 2009 Society of Chemical Industry
Effect of active smoking on asthma symptoms, pulmonary function, and BHR in adolescents
Authors: Yoo S. , Kim H.B. , Lee S.Y. , Kim B.S. , Kim J.H. , Yu J. , Kim B.J. , Lee D.H. , Seong M.W. , Hong S.J.
Published: September 2009

Background

Active smoking is known to increase asthma symptoms and bronchial hyper‐responsiveness (BHR) while decreasing pulmonary function in adults, but few studies have addressed these issues in adolescents.

Methods

We conducted a cross‐sectional survey involving questionnaires and assessment of urinary cotinine levels among 1,492 adolescents from three urban areas of South Korea. Current smoking was defined as having smoked more than 1 day in the prior 30 days or having urine cotinine levels ≥100 ng/ml. Spirometry, skin tests, and methacholine challenge tests were performed on adolescents in Seoul (n = 724).

Results

The prevalence of current smoking was 8.2% in boys and 2.4% in girls. Reports of wheeze and exercise‐induced wheeze in the previous 12 months were more frequent in smokers than nonsmokers (15.2% vs. 8.5%, P = 0.024, and 20.4% vs. 10.7%, P = 0.004, respectively). In multiple logistic regression analysis, current smoking was found to be a significant risk factor for having wheezed in previous 12 months (OR = 4.5, 95% CI 1.5–13.2) and having exercise‐induced wheezing in previous 12 months (OR = 8.7, 95% CI, 3.7–20.9). The subgroup analysis revealed that the FEV1/FVC was lower in smokers than nonsmokers (mean ± SD, 105.1 ± 8.6% vs. 107.8 ± 7.8%, P = 0.019). In contrast, there was no significant difference in BHR. The effect of smoking on asthma symptoms were more pronounced in non‐atopic compared with atopic adolescents.

Conclusion

Current smoking was significantly associated with symptoms of asthma, such as having recent wheezing and recent exercise‐induced wheezing, especially for non‐atopics, in Korean adolescent population. Current smoking was further associated with lower pulmonary function, but not BHR. Pediatr Pulmonol. 2009; 44:954–961. ©2009 Wiley‐Liss, Inc.
Plant explosion emphasizes importance of implementing PSM
Authors: Howell Peter Paul
Published: September 2009

A few years ago, there was an explosion in a reactor at the XYZ Chemical Company. The reactor was a block copolymerization reactor where butadiene and styrene monomers were added in a semibatch manner. The heat of reaction was removed by means of a refrigeration system. The incident occurred when the reactants were not added in the sequence or quantity required. The resulting runaway reaction overpressurized the reactor system and caused an expansion joint to rupture. The hydrocarbons released formed a vapor cloud that exploded, causing the death of two workers, serious injury to three others, and significant damage to the facility.

The contributing causes of the incident include: (a) lack of information about the hazards of the chemicals in the process, (b) lack of information about the equipment in the process and inadequate equipment, (c) inadequate or no PHA, (d) inadequate training, (e) confusing operating procedures, (f) failure to use management of change procedures, (g) failure to perform a prestartup safety review, (h) failure to have an adequate contractor safety program, and (i) failure to investigate previous near misses and incidents and take corrective actions.

This article describes this accident, the root causes, and the major plant deficiencies.

The following expresses my opinion of the events that led to this explosion as testified to in open court. Others may have different opinions. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2010
H∞ filtering for singular systems with time‐varying delay
Authors: Wu Zhengguang , Su Hongye , Chu Jian
Published: September 2009

This paper is concerned with the delay‐dependent H∞ filtering problem for singular systems with time‐varying delay in a range. In terms of linear matrix inequality approach, the delay‐range‐dependent bounded real lemmas are proposed, which guarantee the considered system to be regular, impulse free and exponentially stable while satisfying a prescribed H∞ performance level. The sufficient conditions are proposed for the existence of linear H∞ filter. Numerical examples are given to demonstrate the effectiveness and the benefits of the proposed methods. Copyright © 2009 John Wiley & Sons, Ltd.
Should auld acquaintance be forgot? the reverse transfer of knowledge through mobility ties
Authors: Corredoira Rafael A. , Rosenkopf Lori
Published: September 2009

While mobility's effect on knowledge transfer to firms that hire mobile employees is well demonstrated, we choose to explore mobility's effect on knowledge transfer to firms that lose these employees. Focusing on this ‘outbound mobility’ allows us to isolate effects of social mechanisms associated with mobility. We find that semiconductor firms losing employees are more likely to subsequently cite patents of firms hiring these employees, suggesting that mobility‐driven knowledge flows are bidirectional. In addition, the outbound mobility effect is pronounced when mobility occurs between geographically distant firms, but attenuates for geographically proximate firms since other redundant knowledge channels exist within regions. Copyright © 2009 John Wiley & Sons, Ltd.
Acquisition vs. internal development as modes of market entry
Authors: Lee Gwendolyn K. , Lieberman Marvin B.
Published: September 2009

An established firm can enter a new product market through acquisition or internal development. Predictions that the choice of market entry mode depends on ‘relatedness’ between the new product and the firm's existing products have repeatedly failed to gain empirical support. We resolve ambiguity in prior work by developing dynamic measures of relatedness, and by making a distinction between entries inside vs. outside a firm's primary business domain. Using a fine‐grained dataset on the telecommunications sector, we find that inside a firm's primary business domain, acquisitions are used to fill persistent gaps near the firm's existing products, whereas outside that domain, acquisitions are used to extend the enterprise in new directions. Copyright © 2009 John Wiley & Sons, Ltd.
Pricing response to entry and agglomeration effects
Authors: McCann Brian T. , Vroom Govert
Published: September 2009

In contrast to the traditional approach that typically views entry solely as a threat, we argue that our understanding of this important phenomenon will remain incomplete until we consider the possibility that entry may also provide opportunity for incumbent firms. Drawing from agglomeration theory, which describes the benefit from colocating with competitors, we explicitly examine the combined impact of the competitive and agglomeration effects of entry using a unique dataset of Texas hotels. We find that incumbent establishments price higher when facing entrants whose agglomeration benefits are more likely to outweigh their competitive effects. This association is stronger for incumbents that have greater experience with entry. Our results bring a new perspective to the entry response literature helping clarify inconsistent empirical results. Further, we apply agglomeration theory to a new question, incumbent behavior, and demonstrate that experience appears to play an important role in recognizing situations that generate agglomeration externalities. Copyright © 2009 John Wiley & Sons, Ltd.
Characteristics of various elastomeric bearings in tension
Authors: Mangerig Ingbert , Mano Toshihisa
Published: September 2009

It has been a long time since seismic isolation was invented with the aim of protecting lives and structures against earthquakes. Seismic isolation is achieved by installing special bearings, so‐called isolators, between the foundations of buildings or the piers of bridges and the superstructure. These isolators support the structure in the vertical direction and at the same time allow horizontal movements during earthquakes so that the seismic force applied to the superstructure can be much reduced. In Japan elastomeric bearings are often used for this purpose and existing seismic‐isolated structures have demonstrated their effectiveness in the past. A number of research projects concerning elastomeric bearings have been carried out and their performance with respect to compression and shear loads is well understood. However, not much attention has been paid to their characteristics with respect to tensile loads. In some design standards a certain degree of tension in rubber bearings is already allowed to occur during earthquakes. This is inevitable since the ability of rubber to sustain tension was discovered and in seismic isolation applications in high‐rise buildings and bridges there is a possibility that isolators undergo tension due to the overturning moment. There are, however, still many uncertainties; for instance, the influence of damage to or cavities within the rubber caused by tension, the interaction between the shapes and dimensions of bearings and the tensile strength, and the influence of the out‐of‐plane deformation of flanges are not well understood. Currently, the Japanese design rules for both bridges and buildings regulate the allowable tensile stress without distinguishing the type of rubber, shapes or dimensions. This merely empirical value will need to be reconsidered.
A study of the new construction method for transverse box culverts by using the steel‐concrete composite sandwich deck slab – cutting the cost of constructing expressways
Authors: Ishikawa Hiroyuki , Konno Hisashi , Mitamura Hiroshi
Published: September 2009

Expressways are typically constructed on high embankments to accommodate transverse box culverts. If the embankment height could be reduced while still accommodating culverts, then the road construction costs could be lowered by reducing the required volume of embankment soil. The authors achieved this by devising a transverse box culvert whose steel‐concrete composite sandwich deck slab resembles the composite slabs used for road bridges.

The slab was tested indoors for bending failure, punching shear failure and fatigue strength under cyclic wheel loading. It was tested in an expressway for loading by heavy vehicles. The experiments demonstrated the soundness of the design method.

This paper describes the design and construction of this structure, and the results of the indoor and outdoor experiments.
Estimation of punching shear fatigue strength for steel plate‐concrete composite decks
Authors: Kaido Hiroshi , Matsui Shigeyuki
Published: September 2009

In Japan a steel plate‐concrete composite deck, i.e. concrete connected to steel base plates with shear studs, is called a Robinson‐type deck. In order to decrease the deflection of the steel base plate due to the weight of the concrete, the steel base plate is stiffened with steel lateral ribs. In recent years the composite deck has been used for many highway bridge decks, such as steel twin‐girder bridges, open‐section steel box girder bridges, etc. Its predominant failure mode was discovered to be punching shear failure by repetition of wheel loads. In this paper the authors derive the estimation formula for the punching shear fatigue strength of the composite deck from the results of wheel trucking tests. Furthermore, the relationship between the non‐dimensional strength ratio of an applied load divided by the punching shear strength and the number of cycles until failure was confirmed and plotted on the S‐N curve for an RC slab. Therefore, the fatigue design of the composite deck can be executed reasonably with the S‐N curve.
The North Bridge in Warsaw
Authors: Schmiers Thomas , Sprinke Peter , Stein Thomas
Published: September 2009

Warsaw, the capital of Poland, is developing into an important metropolis of Central Europe. With approx. 1.7 million inhabitants, Warsaw is one of the biggest cities and an important centre for traffic, economy and trade in Central and Eastern Europe, and within the European Union (Fig. 1). Warsaw is the principal focus of investment in Poland and of great political and cultural significance.

The cityscape is characterized by the historic old town, by landmarks such as the Culture and Convention Centre and above all by the River Vistula which runs right through Warsaw and divides the city in a natural way.
On the asymptotic behaviour of the 2D Navier‐Stokes equations with Navier friction conditions towards Euler equations
Authors: Guillén‐González F. , Planas G.
Published: September 2009

In this paper, the two dimensional incompressible Navier‐Stokes problem in a bounded domain subject to nonhomogeneous Navier friction boundary conditions is considered. We establish the existence, uniqueness, and regularity of solutions to such problem and we demonstrate convergence towards the incompressible 2D Euler equations in the inviscid limit. We also show the stability and convergence of a time discrete implicit Euler's scheme as both parameters, viscosity and time step, go to zero.
Direct and inverse dipole electromagnetic scattering by a piecewise homogeneous sphere
Authors: Tsitsas N.L.
Published: September 2009

This paper deals with the investigation of the direct and the inverse electromagnetic scattering problem by a piecewise homogeneous sphere, excited by an interior or exterior dipole. The research is motivated by important physical, biomedical, and technological applications detailed in the introduction. First, we utilize Sommerfeld's and T‐matrix method to determine the exact electromagnetic Green's function, that is the solution of the direct scattering problem. Then, we use the low‐frequency assumption to derive asymptotic far‐field expansions of the Green's function of an electrically small piecewise homogeneous sphere. These low‐frequency expansions contribute essentially to the development of far‐field inverse scattering algorithms for the determination of the sphere's geometrical and physical characteristics. It is shown that for these algorithms interior dipoles offer additional information, which may be utilized effectively for the localization and reconstruction of the sphere. Several numerical results exhibit the variations of the far‐field quantities with respect to the dipole's and the sphere's characteristics. Reductions to plane wave scattering by a layered sphere and exterior dipole scattering by a homogeneous sphere are pointed out.
Rolled-Up Nanotech: Illumination-Controlled Hydrofluoric Acid Etching of AlAs Sacrificial Layers
Authors: Costescu Ruxandra M , Deneke Christoph , Thurmer Dominic J , Schmidt Oliver G
Published: September 2009

The effect of illumination on the hydrofluoric acid etching of AlAs sacrificial layers with systematically varied thicknesses in order to release and roll up InGaAs/GaAs bilayers was studied. For thicknesses of AlAs below 10 nm, there were two etching regimes for the area under illumination: one at low illumination intensities, in which the etching and releasing proceeds as expected and one at higher intensities in which the etching and any releasing are completely suppressed. The “etch suppression” area is well defined by the illumination spot, a feature that can be used to create heterogeneously etched regions with a high degree of control, shown here on patterned samples. Together with the studied self-limitation effect, the technique offers a way to determine the position of rolled-up micro- and nanotubes independently from the predefined lithographic pattern.
Effects of acrolein, a natural occurring aldehyde, on the anticoagulant serpin antithrombin
Authors: Martínez-Martínez I. , Ordóñez A. , Guerrero J.A. , Pedersen S. , Miñano A. , Teruel R. , Velázquez L. , Kristensen S.R. , Vicente V. , Corral J.
Published: September 2009

We studied the effect of acrolein, an α,β‐unsaturated aldehyde that causes adduct‐modification of lysine, cysteine, and histidine residues, on antithrombin, a key anticoagulant serpin. Intrinsic fluorescence, functionality (anti‐FXa and anti‐IIa activity), heparin affinity and conformational features of plasma and purified antithrombin were evaluated. In vivo experiments were carried out in mice. Intrinsic fluorescence showed a two‐step conformational change. Acrolein, even at low dose, impaired the anticoagulant function of purified antithrombin by affecting its heparin affinity. However, higher concentrations of acrolein and long incubations are required to cause mild functional effects on plasma antithrombin and mice.
PHYSIOLOGICAL BASIS OF YIELD VARIATION OF TEA (CAMELLIA SINENSIS) DURING DIFFERENT YEARS OF THE PRUNING CYCLE IN THE CENTRAL HIGHLANDS OF SRI LANKA
Authors: DE COSTA W. A. J. M. , NAVARATNE D. M. S. , ANANDACOOMARASWAMY A.
Published: September 2009

The objective of this study was to elucidate the physiological basis of the significant yield decline that occurs during the fourth year of the pruning cycle of tea. Biomass partitioning, which was hypothesized to be a major factor in causing this yield decline, was measured by destructive harvests of entire tea bushes, in two contrasting, mature, field-grown tea cultivars (TRI 2025 and DT1) at the end of different years of the pruning cycle. In both cultivars, yield showed continuous increases from year 1 to 3, followed by reductions of 44% and 35% in TRI2025 and DT1 respectively in the fourth year. Patterns of biomass partitioning to roots, stems or branches did not correlate with the above yield variation whereas harvest index, canopy leaf area index and mature leaf dry weight showed variations which paralleled the yield variation. The fourth-year decline in harvest index was brought about by reductions in both shoot number per m2 and mean individual shoot weight, which indicate a reduction in sink strength. Both cultivars showed reductions in light-saturated photosynthetic rate of maintenance foliage during the second half of the pruning cycle, indicating reduced source capacity. Hence, a combined reduction of both sink strength and source capacity during the fourth year could have brought about the significant yield reduction in tea. A significant increase of root starch in the fourth year indicated a down-regulation of physiological activities of the bush towards the end of the pruning cycle. Mechanisms responsible for this down-regulation need to be elucidated by further research.
A Portfolio Optimality Test Based on the First-Order Stochastic Dominance Criterion
Authors: Kopa Miloš , Post Thierry
Published: September 2009

Existing approaches to testing for the efficiency of a given portfolio make strong parametric assumptions about investor preferences and return distributions. Stochastic dominance-based procedures promise a useful nonparametric alternative. However, these procedures have been limited to considering binary choices. In this paper we take a new approach that considers all diversified portfolios and thereby introduce a new concept of first-order stochastic dominance (FSD) optimality of a given portfolio relative to all possible portfolios. Using our new test, we show that the U.S. stock market portfolio is significantly FSD nonoptimal relative to benchmark portfolios formed on market capitalization and book-to-market equity ratios. Without appealing to parametric assumptions about the return distribution, we conclude that no nonsatiable investor would hold the market portfolio in the face of the attractive premia of small caps and value stocks.
Wave-power extraction by a compact array of buoys
Authors: GARNAUD XAVIER , MEI CHIANG C.
Published: September 2009

The majority of existing single-unit devices for extracting power from sea waves relies on resonance at the peak frequency of the incident wave spectrum. Such designs usually call for structural dimensions not too small compared to a typical wavelength and yield high efficiency only within a limited frequency band. A recent innovation in Norway departs from this norm by gathering many small buoys in a compact array. Each buoy is too small to be resonated in typical sea conditions. In this article a theoretical study is performed to evaluate this new design. Within the framework of linearization, we consider a periodic array of small buoys with similarly small separation compared to the typical wavelength. The method of homogenization (multiple scales) is used to derive the equations governing the macroscale behaviour of the entire array. These equations are then applied to energy extraction by an infinite strip of buoys, and by a circular array. In the latter case, advantages are found when compared to a single buoy of equal volume.
Immune responses to polyethylenimine-mannose-delivered plasmid DNA encoding aFasciola giganticafatty acid binding protein in mice
Authors: Smitha S. , Raina O.K. , Singh B.P. , Samanta S. , Velusamy R. , Dangoudoubiyam S. , Tripathi A. , Gupta P.K. , Sharma Bhaskar , Saxena Meeta
Published: September 2009

Fasciola giganticafatty acid binding protein (FABP) was evaluated for evoking an immune response in mice, by delivering the gene coding for this protein with mannosylated-polyethylenimine (PEI) to peritoneal cells. Mice were immunized with 50 μg recombinant plasmid DNA (Group I) or DNA-PEI-mannose (a 22 kDa linear cationic polymer with mannose ligand) (Group II) via the intraperitoneal route. Antibody studies showed no significant humoral immune response evoked to this DNA immunization with either PEI-mannose-delivered or naked DNA. However, on protein boosting of these DNA-primed mice there was a significant enhancement of antibody titre. Flow cytometric bead array was used to measure quantitites of interleukin (IL)-2, IL-4, IL-5, interferon-γ (IFN-γ) and tumour necrosis factor (TNF) cytokines. Overexpression of T-helper 1 (Th1) cytokines such as IFN-γ and TNF, with a lower but significant expression of the T-helper 2 (Th2) cytokine IL-5 was detected. Gene delivery using polyethylenimine-mannose ligand showed significant expression of IFN-γ and TNF (P < 0.05), but no significant difference in IL-2, IL-4 and IL-5 (P>0.05) cytokine expression was observed between naked-DNA- and mannosylated PEI-DNA-delivered mice. Naked- or PEI-delivered-DNA immunization produced insignificant levels of IL-2 and IL-4 (P>0.05) cytokines in both groups of mice.
Intestinal parasites of the Arctic fox in relation to the abundance and distribution of intermediate hosts
Authors: STIEN A. , VOUTILAINEN L. , HAUKISALMI V. , FUGLEI E. , MØRK T. , YOCCOZ N. G. , IMS R. A. , HENTTONEN H.
Published: September 2009

The intestinal parasite community of Arctic foxes (Vulpes lagopus) on the Svalbard archipelago in the High Arctic was investigated in relation to the abundance and distribution of intermediate hosts. Five species of cestodes (Echinococcus multilocularis, Taenia crassiceps, Taenia polyacantha, Taenia krabbei and Diphyllobothrium sp.), ascaridoid nematodes and one unidentified acanthocephalan species were found. The cestodes E. multilocularis, T. crassiceps and T. polyacantha all showed a decreasing prevalence in the fox population with increasing distance from their spatially restricted intermediate host population of sibling voles (Microtus levis). In addition, the prevalence of E. multilocularis in a sample from the vole population was directly related to the local vole abundance. The cestode T. krabbei uses reindeer as intermediate host, and its prevalence in female foxes was positively related to the density of reindeer (Rangifer tarandus platyrhyncus). Finally, the prevalence of the ascaridoid nematodes also decreased with increasing distance from the vole population, a finding that is consistent with the idea that voles are involved in transmission, most likely as paratenic hosts. The prevalence of the remaining species (Diphyllobothrium sp. and an unidentified acanthocephalan) was very low. We conclude that the distribution and abundance of intermediate host structure the gastrointestinal parasite community of the Arctic fox on the Svalbard archipelago.
Contrasting reservoirs for Schistosoma japonicum between marshland and hilly regions in Anhui, China – a two-year longitudinal parasitological survey
Authors: LU DA-BING , WANG TIAN-PING , RUDGE JAMES W. , DONNELLY CHRISTL A. , FANG GUO-REN , WEBSTER JOANNE P.
Published: September 2009

Schistosoma japonicum remains highly endemic in many counties in China and has recently re-emerged, to a large extent, in previously controlled areas. To test the hypothesis that small rodents and less agriculturally important domestic animals such as dogs and cats may play an important role in the transmission and potential re-emergence of this disease, an annual investigation of S. japonicum among humans, domestic animals and rodents, combined with detailed surveys of the snail intermediate host, was performed across 3 marshland villages and 3 hilly villages in Anhui province of China over 2 consecutive years. The highest infection prevalence and intensity observed across all mammals was in rodents in the hilly region; while in the marshland, bovines were suspected as the main reservoirs. However, relatively high infection prevalence levels were also found in dogs and cats in both regions. Such results may have implications for the current human- and bovine-oriented control policy for this medically and veterinarily important disease, particularly within the hilly regions of mainland China.
Trichomonas vaginaliskills and eats – evidence for phagocytic activity as a cytopathic effect
Authors: MIDLEJ V. , BENCHIMOL M.
Published: September 2009

This study reports that the cytopathic effect ofTrichomonas vaginalis, an important human parasite of the urogenital tract, occurs due to mechanical stress and subsequent phagocytosis of the necrotic cells. The investigation was done using a primary culture of bovine oviduct epithelial cells (BOECs), grown either in monolayers or as floating cells. Trophozoites displaying different virulence levels were co-incubated with BOECs for times varying between 1 min and 48 h. Analyses were performed using videomicroscopy, scanning and transmission electron microscopy, colourimetric assays and cytochemistry. Injury was observed as early as 1 h after incubation, while after 12 h the host cells were severely damaged when a fresh trichomonad isolate was used. Trichomonads attack the host cells by clustering around them. Mechanical stress on the microvilli of the host cells was observed and appeared to induce plasma membrane damage and cell death. After membrane injury and lysis, fragments of the necrotic cells were ingested by trichomonads. Phagocytosis occurred by trichomonads avidly eating large portions of epithelial cells containing the nucleus and other organelles, but living or intact cells were not ingested. Necrotic fragments were rapidly digested in lysosomes, as shown by acid phosphatase and ruthenium red assays where only the BOECs were labelled. The lytic capacity of the trichomonads was more pronounced in host cell suspensions.
Griffith Taylor's Antarctica: science, sentiment, and politics
Authors: Strange Carolyn
Published: September 2009

Griffith Taylor (1880–1963) was a scientific member of theTerra Novaexpedition. Although he published initially on his geomorphological, glaciological and meteorological research, conducted between 1910 and 1912, he was also a teacher, lecturer, publicist and later political commentator on Antarctica. Initially a loyal ‘Britisher’ he developed an internationalist perspective on Antarctica without compromising his self-promotional ambitions. Through his professional career in Australia, the US and Canada over the early to mid twentieth century Antarctica's shifting scientific, cultural and political history can be mapped. Just as self-interest permeated the Antarctic Treaty of 1959, so Taylor's ambitions persisted as he fashioned himself into a scientific prophet for peace. Taylor's Antarctica, an amalgam of sentiment and science, rivalry and cooperation, imperialism and internationalism, popular culture and global politics, was the twentieth century's Antarctica.
Inuit vulnerability and adaptive capacity to climate change in Ulukhaktok, Northwest Territories, Canada
Authors: Pearce Tristan , Smit Barry , Duerden Frank , Ford James D. , Goose Annie , Kataoyak Fred
Published: September 2009

Climate change is already being experienced in the Arctic with implications for ecosystems and the communities that depend on them. This paper argues that an assessment of community vulnerability to climate change requires knowledge of past experience with climate conditions, responses to climatic variations, future climate change projections, and non-climate factors that influence people's susceptibility and adaptive capacity. The paper documents and describes exposure sensitivities to climate change experienced in the community of Ulukhaktok, Northwest Territories and the adaptive strategies employed. It is based on collaborative research involving semi-structured interviews, secondary sources of information, and participant observations. In the context of subsistence hunting, changes in temperature, seasonal patterns (for example timing and nature of the spring melt), sea ice and wind dynamics, and weather variability have affected the health and availability of some species of wildlife important for subsistence and have exacerbated risks associated with hunting and travel. Inuit in Ulukhaktok are coping with these changes by taking extra precautions when travelling, shifting modes of transportation, travel routes and hunting areas to deal with changing trail conditions, switching species harvested, and supplementing their diet with store bought foods. Limited access to capital resources, changing levels of traditional knowledge and land skills, and substance abuse were identified as key constraints to adaptation. The research demonstrates the need to consider the perspectives and experiences of local people for climate change research to have practical relevance to Arctic communities such as for the development and promotion of adaptive strategies.
Additional documents and survey on the Franklin sites of Beechey Island, Nunavut, Canada
Authors: Hansen Todd
Published: September 2009

Documents are presented adding further insights into a survey of gravesite memorials on Beechey Island, as well as locating the additional sites of the Franklin expedition noted in the Franklin search literature. These are augmented with current photographs.
Toward lean minimally invasive robotic surgery
Authors: Zoppi Matteo , Khan Mohammed Aamir , Schäfer Felix , Molfino Rezia
Published: September 2009

Developed minimally invasive surgical (MIS) robots are large multi-arm, multipurpose systems requiring significant investments that limit their availability in hospitals. A larger distribution of MIS robots with benefit for patients might be achieved improving their modularity and scalability so that smaller hospitals or medical centers could decide for a simpler and lower cost setup for a limited number of treatments only, while centers with higher funding could have more systems dedicated to different classes of operations. In line with this statement the paper proposes the paradigm of lean MIS system comprising a scalable set of modular, agile, small size single-instrument robots with limited life cycle cost. Miniaturization of instruments can further reduce invasiveness of procedures and one promising research direction is needle laparoscopic surgery, which can be applied to classes of operations on small regions requiring small force interaction with the patient. In the paper the development of a lean single-instrument manipulator for needlescopic surgery is presented and a new master concept for accurate restitution of surgical force proposed and discussed.
Toward an optimal performance index for neurosurgical robot's design
Authors: Gasparetto Alessandro , Zanotto Vanni
Published: September 2009

In the past years a large number of new surgical devices have been developed to improve the operation outcomes and reduce the patient's trauma. Nevertheless, the dexterity and accuracy required in positioning the surgical tools are often unreachable if the surgeons are not assisted by a suitable system. Since a medical robot works in an operating room, close to the patient and the medical staff, it has to satisfy much stricter requirements with respect to an industrial one. From a kinematic point of view, the robot must reach any target position in the patient's body, being as less invasive as possible for the surgeon's workspace. In order to meet such requirements, the right robot structure has to be chosen by means of the definition of suitable kinematic performance indices.

In this paper some task-based indices based on the robot workspace and stiffness are presented and discussed. The indices will be used in a multiobjective optimization problem to evaluate best robot kinematic structure for a given neurosurgical task.
Virtual fixtures with autonomous error compensation for human–robot cooperative tasks
Authors: Castillo-Cruces Raúl A. , Wahrburg Jürgen
Published: September 2009

This paper presents a control strategy for surgical interventions, applied on a human–robot cooperative system, which facilitates the sharing of responsibilities between surgeon and robot. The controller utilizes virtual fixtures to constrain the movements of the end-effector into a predefined path or region. Possible deviation error can be compensated in two different ways: (a) manual compensation and (b) autonomous compensation. With manual compensation, the system defines both virtual fixtures and error compensation directions, but the surgeon must apply manual forces himself/herself in order to generate end-effector motion. With autonomous compensation, a clear distribution of responsibilities between surgeon and robotic system is present, meaning the surgeon has complete control of the end-effector along the preferred directions, while the robot autonomously compensates for any deviation along the non-preferred directions.
Improved knowledge management through first-order logic in engineering design ontologies
Authors: Witherell Paul , Krishnamurty Sundar , Grosse Ian R. , Wileden Jack C.
Published: September 2009

This paper presents the use of first-order logic to improve upon currently employed engineering design knowledge management techniques. Specifically, this work uses description logic in unison with Horn logic, to not only guide the knowledge acquisition process but also to offer much needed support in decision making during the engineering design process in a distributed environment. The knowledge management methods introduced are highlighted by the ability to identify modeling knowledge inconsistencies through the recognition of model characteristic limitations, such as those imposed by model idealizations. The adopted implementation languages include the Semantic Web Rule Language, which enables Horn-like rules to be applied to an ontological knowledge base and the Semantic Web's native Web Ontology Language. As part of this work, an ontological tool, OPTEAM, was developed to capture key aspects of the design process through a set of design-related ontologies and to serve as an application platform for facilitating the engineering design process. The design, analysis, and optimization of a classical I-beam problem are presented as a test-bed case study to illustrate the capabilities of these ontologies in OPTEAM. A second, more extensive test-bed example based on an industry-supplied medical device design problem is also introduced. Results indicate that well-defined, networked relationships within an ontological knowledge base can ultimately lead to a refined design process, with guidance provided by the identification of infeasible solutions and the introduction of “best-case” alternatives. These case studies also show how the application of first-order logic to engineering design improves the knowledge acquisition, knowledge management, and knowledge validation processes.
Approximating shapes with hierarchies and topologies
Authors: Krstic Djordje
Published: September 2009

This is the second paper in the series on shape decompositions and their use as shape approximations. This time we investigate hierarchical and topological shape decompositions or hierarchies and topologies. We showed earlier that bounded decompositions behave the same way as shapes do. The same holds for hierarchies and topologies, which are special kinds of bounded decompositions. They are distinguished by their algebraic structures, which have many important properties to facilitate their application as shape approximations. We provide an account of their properties with an emphasis on their application.
Diagnosis of hepatitis C virus infection in Scotland's injecting drug user population
Authors: McDONALD S. A. , HUTCHINSON S. J. , MILLS P. R. , BIRD S. M. , ROBERTSON C. , DILLON J. F. , SPRINGBETT A. , GOLDBERG D. J.
Published: September 2009

We estimated the extent of undiagnosed hepatitis C virus (HCV) infection in injecting drug users (IDUs) in Scotland. We used record-linkage to determine HCV diagnosis status for 41 062 current/former IDUs attending drug treatment and support services between 1 April 1995 and 31 March 2006; the extent of undiagnosed HCV infection was estimated by comparing the number HCV-diagnosed to the number HCV-infected (estimated from an unlinked anonymous testing survey of 2141 current/former IDUs). In all, 9145 IDUs (22%) were diagnosed HCV antibody-positive since first attendance at drug services (diagnosis rate of 33·6/1000 person-years, 95% CI 32·7–34·4). By 31 March 2006, of the 19 632 current/former IDUs who had attended drug services and were determined to be living with HCV, an estimated 58% (95% CI 45–62) had not been HCV-diagnosed. It is essential that the deployment of resources for identifying at-risk IDUs with a view to offering antiviral therapy is guided by evidence.
A spectral model for signal elements isolated from zebrafish photopic electroretinogram
Authors: NELSON RALPH F. , SINGLA NIRMISH
Published: September 2009

The zebrafish photopic electroretinogram (ERG) sums isolatable elements. In each element, red-, blue-, green-, and UV- (r, g, b, and u) cone signals combine in a way that reflects retinal organization. ERG responses to monochromatic stimuli of different wavelengths and irradiances were recorded on a white rod suppressing background using superfused eyecups. Onset elements were isolated with glutamatergic blockers and response subtractions. CNQX-blocked ionotropic (AMPA/kainate) glutamate receptors; l-AP4 or CPPG-blocked metabotropic (mGluR6) glutamate receptors; TBOA-blocked glutamate transporters; and l-aspartate inactivated all glutamatergic mechanisms. Seven elements emerged: photopic PIII, the l-aspartate-isolated cone response; b1, a CNQX-sensitive early b-wave element of inner retinal origin; PII, a photopic, CNQX-insensitive composite b-wave element from ON bipolar cells; PIIm, an l-AP4/CPPG-sensitive, CNQX-insensitive, metabotropic subelement of PII; PIInm, an l-AP4/CPPG/CNQX-insensitive nonmetabotropic subelement of PII; a1nm, a TBOA-sensitive, CNQX/l-AP4/CPPG-insensitive, nonmetabotropic, postphotoreceptor a-wave element; and a2, a CNQX-sensitive a-wave element linked to OFF bipolar cells. The first five elements were fit with a spectral model that demonstrates independence of cone–color pathways. From this, Vmax and half-saturation values (k) for the contributing r-, g-, b-, and u-cone signals were calculated. Two signal patterns emerged. For PIII or PIInm, the Vmax order was Vr > Vg >> Vb ≈ Vu. For b1, PII, and PIIm, the Vmax order was Vr ≈ Vb > Vg > Vu. In either pattern, u-cone amplitude (Vu) was smallest, but u-cone sensitivity (ku362) was greatest, some 10–30 times greater than r cone (kr570). The spectra of b1/PII/PIIm elements peaked near b- and u-cone absorbance maxima regardless of criteria, but the spectra of PIII/PIInm elements shifted from b- toward r-cone absorbance maxima as criterion levels increased. The greatest gains in Vmax relative to PIII occurred for the b- and u-cone signals in the b1/PII/PIIm b-wave elements. This suggests a high-gain prolific metabotropic circuitry for b- and u-cone bipolar cells.
An evaluation of sponge-associated amphipods from the Antarctic Peninsula
Authors: Amsler Margaret O. , Mcclintock James B. , Amsler Charles D. , Angus Robert A. , Baker Bill J.
Published: September 2009

Nearshore marine benthic algal communities along the western Antarctic Peninsula harbour extremely high densities of amphipods that probably play important roles in nutrient and energy flow. This study extends our evaluation of the importance of amphipods in the nearshore Antarctic Peninsular benthic communities and focuses on sponge associations. We found a mean density of 542 amphipods per litre (L) sponge for twelve species of ecologically dominant sponges. The highest mean density (1295 amphipods per L sponge) occurred withDendrilla membranosaPallas. The amphipod community associated with the 12 sponges was diverse (38 species), with mean species richness values ranging from two to eight species. Mean Shannon diversity indices (H’) ranged from 0.52 to 1.49. Amphipods did not appear to have obligate host relationships. Qualitative gut content analyses indicated that 12 of the 38 amphipod species were found with sponge spicules in their guts. However, only one of the amphipods,Echiniphimedia hodgsoniWalker, had considerable amounts of spicules in the gut. Organic lipophilic and hydrophilic extracts of the twelve sponges were presented in alginate food disks to a sympatric omnivorous amphipod in feeding bioassays and extracts of only two sponges deterred feeding.